[A]

AASHTO (American Association of State Highway and Transportation Officials)A regulatory organization which governs the design and specifications of highway bridges.AccessoriesAre extra items that can be furnished in addition to the base joist or joist girder. They include: headers, top chord extensions, extended ends, ceiling extensions, bottom chord extensions, sloped end bearings, bridging, bridging anchors, joist girder bottom chord bracing, or angle units (joist substitutes).ADLAbbrevation for 'After Dead Load is Applied'.AestheticHaving the sense of beauty or pleasing to the eye.AFFAbbrevation for 'Above Finish Floor'.AGA (American Galvanizers Association)A non-profit association representing the post-fabrication hot-dip galvanizing industry.AGCA (Associated General Contractors of America)Is a national trade organization of qualified construction contractors and and industry related companies dedicated to skill, integrity, an responsibility. The AGCA is the voice of the construction industry and is dedicated to improving the quality of construction and protecting the public.AIA (American Institute of Architects)An organization to unite in fellowship the members of the architectural profession in the United States.AISC (American Institute of Steel Construction, Inc.)Is a non-profit technical specifying and trade organization for the fabricated structural steel industry in the United States. It was founded in 1921 with headquarters located in Chicago. One of their best known manuals is the Manual of Steel Construction.AISE (Association of Iron and Steel Engineers)Abbreviation.AISI (American Iron and Steel Institute)An institute to promote the interests of the iron and steel industry.Alignment Chart for ColumnsA nomograph for estimating the effective length factor, K, of columns in an unbraced frame. Note that the chart is based upon assumptions of idealized conditions which seldom exist in real structures.AmplitudeA measure of floor vibration. It is the magnitude or total distance traveled by each oscillation of the vibration.Amplification FactorA multiplier of the value of moment or deflection in the unbraced length of an axially loaded member to reflect secondary values generated by the eccentricity of the load.Anchor BoltA long 'L' shaped bolt which is set in concrete and used to anchor columns or other members to a foundation or other support.Anchor Bolt PlanA plan view showing the size, location, and projection of all anchor bolts.AnchorageThe process of fastening a joist or joist girder to a masonry, concrete, or steel support by either bolting or welding.AngleA hot rolled shape called an Angle with symbol L which has equal legs or unequal legs.Angle UnitA member used as a joist substitute which is intended for use at very short spans (10 feet or less) where open web steel joists are impractical. They are usually used for short spans in skewed bays, over corridors, or for outriggers. It can be made up of two or four angles to form channel sections or box sections. Tube and channel sections are also used. See Joist Substitute.ANSI (American National Standards Institute)A nonprofit organization which promotes the use of U.S. standards internationallyApexThe highest point on a joist or joist girder where the sloped chords meet. See also Peak.Approval PlansPlans sent by the joist manufacturer to the buyer, engineer, architect, contractor or other person for approval. The plans may include a framing plan, elevations, sections, and a material list.AreaUnit of measure of length times width expressed in square inches.

Arched JoistA non-standard type of joist where both the top chord and bottom chord are curved parallel with each other.ArchitectA person who designs buildings or other structures and has completed schooling in building design or similar subjects and is licensed by the state as an architect.ASCE (American Society of Civil Engineers)Founded in 1852, is the oldest national professional engineering society in the United States. It is dedicated to the advancement of the individual civil engineer and the civil engineering profession through education.ASD (Allowable Stress Design)A structural design method whereby a structural element is designed so that the unit stresses computed under the action of working or service loads do not exceed specified allowable values. See Working Stress Design and Elastic Design.Aspect RatioFor any rectangular configuration, the ratio of the lengths of the sides.ASTM (American Society for Testing and Materials)An organization which has developed over 10,000 technical standards which are used by industries worldwide.AtriumAn opening or skylighted lobby through two or more floor levels other than an enclosed stairway, elevator, etc.AutoCADThe world's most popular computer-aided drafting software product for the personal computer in both DOS and windows by Autodesk, Inc. Anything that can be drawn on a drawing board can be drawn by AutoCAD.Automatic WeldingA welding procedure using a machine to make a weld.Auxiliary LoadAny dynamic live loads such as cranes, monorails, and material handling systems.AWI (American Welding Institute)An organization established in 1984 to bridge the gap between the findings of basic welding research and the needs of the industry.AWS (American Welding Society)A non-profit organization whose major goal is to advance the science, technology, and application of welding and related joining disciplines.Axial ForceA force tending to elongate or shorten a member.Axial CompressionAn axial force causing compression in a member.Axial LoadA load whose line of action passes through the centroid of the member's cross-sectional area and is perpendicular to the plane of the section.Axial Strut LoadA structural member designed to transfer a axial tension or compression load only.Axial TensionAn axial force causing tension in a member.[Return to Glossary][B]

Backing BarA welding aid used to prevent melting through of a joint when preforming, for example, a complete-joint penetration groove weld.BalconyAn elevated platform or seating space of an assembly room projecting from a wall of a building.Ballast RoofA roof which has selected material, such as crushed stone, placed on its surface to hold down the roof from wind forces.BarA square or round piece of solid steel which is usually 6 inches or less in width.Base MetalThe metal to be welded or cut.Base Plate

A steel plate welded to the base of a column which distributes the column loads over an area of foundation large enough to prevent crushing of the concrete and usually secured by anchor bolts.BasementAny floor below the first story in a building.BattenA small piece of angle or plate welded to the heels of a two angle web member or any two parallel components to tie them together and usually located at the middle of the member.BayThe distance between the main frames of a building.Base PlyIs one layer of felt fastened to the deck over which a built-up roof is applied.BBC (Basic Building Code)A minimum model regulatory code for the protection of public health, safety, welfare and property by regulating and controlling the design, construction, quality of materials, use, occupancy, location and maintenance of all buildings and structures within a jurisdiction.BeamA structural member, usually horizontal, whose main function is to carry loads transverse to its longitudinal axis. These loads usually cause bending of the beam member. Some types of beams are simple, continuous, and cantilever.Beam-ColumnA structural member whose main function is to carry loads both parallel and transverse to its longitudinal axis.Bearing1) The distance that the bearing shoe or seat of a joist or joist girder extends over its masonry, concrete, or steel support 2) A structural support, usually a beam or wall, that is designed by the specifying professional to carry reactions to the foundationBearing PlateThe steel plate used for a joist or joist girder to bear on when they are supported by masonry or concrete supports. This plate transfers the joist reaction to the supporting structure and must be sized accordingly.Bearing WallA wall which is supporting any vertical loads i2n addition to its own weight.Bending MomentThe condition in the analysis of the internal stresses across the cross section of a member when it is subjected to forces which cause it to bend.Bending StressIs zero at the neutral axis and assumed to increase linearly to a maximum at the outer fibers of the section.Formula in the elastic range: Bending stress (in psi)=(M * c)/I, where 'M' is the bending moment at the section in in-lbs, 'I' is the moment of inertia of the section in inches^4, and 'c' is the distance from the neutral axis to the point at which the stress is desired in inches.BentThe plane of beam or joist girder members which support loads and the columns which support these members.Bevel CutA single cut made at an angle to the member length. See Miter Cut.BG-Type Joist GirderA type of Joist Girder where joists are located at all panel points where vertical webs and diagonal webs intersect the top chord.Biaxial BendingBending of a structural member about two perpendicular axes at the same time.BifurcationThe phenomenon whereby a perfectly straight member may either assume a deflected position, deflect then twist out of plane, or may remain in an undeflected configuration.Bill of LadingA list that gives each part or mark number, quantity, length of material, total weight, or other description of each piece of material that is shipped to a jobsite. The receiver compares each item on this list to what is on the truck and signs the statement. See also Shipping List.Bill of MaterialsA list of items or components used for fabrication and accounting purposes. See Cut-List.BlastingA method of cleaning or of roughening a surface by a forceable stream of sharp angular abrasive.Blue PrintAlso called a blue line. Is a copy of an architectural or other drawing made by a special machine usually on white paper with the lines and text being a blue color.BOCA (Building Officials and Code Administrators International, Inc.)A minimum model regulatory code for the protection of public health, safety, welfare and property by regulating and controlling the design, construction, quality of materials, use, occupancy, location and maintenance of all buildings and structures within a jurisdiction. Its serves primarily the North Central and Northeast United States.Bolted SpliceThe connection between two structural members joined at their ends by bolting to form a single, longer member.

Bond BeamThe top course of block of a masonry wall filled with concrete and reinforcing steel and used to support roof loads.Bottom BearingA bearing condition where the joist or joist girder bears on its bottom chord and not at an underslung condition.Bottom ChordThe bottom members of a joist or joist girder.Bottom Chord Extension (BCX)The two angle extended part of a joist bottom chord from the first bottom chord panel point towards the end of the joist.Bottom Chord StrutA bottom chord of a joist or joist girder designed to transfer a axial tension or compression load.Boundary ConditionAn idealization to model how a structure is attached to its "external" points of support, for example, pin, fixed, roller, or shear release.Bow String JoistA non-standard type of joist where the top chord is curved and the bottom chord is straight or level.Bow's NotationUsed in a graphical analysis of a joist or joist girder. It is a notation for denoting truss joints, members, loads, and forces. Capital letters are placed in the spaces between truss members and between forces. Each member and load is then designated by the letters on opposite sides of it.Braced FrameA frame which resists lateral loads by the use of diagonal bracing, K-braces, or other system of bracing.BracketA structural support attached to a column or wall on which to fasten another structural member.Bridge CraneA lifting system which has a hoist that moves laterally on a beam or other member which then in turn moves longitudinally on a runway made of beams and rails.BridgingIn general, is a member connected to a joist to brace it from lateral movement. See Horizontal Bridging and Diagonal Bridging.Bridging AnchorAn angle or bent plate attached to a wall where the bridging will be attached or anchored, either by welding or bolting. The ends of all bridging lines terminating at walls or beams shall be anchored thereto.Bridging ClipA small piece of angle or plate with a hole or slot that is welded to the top and bottom chord angles so that bridging may be attached.Bridging DiagramA diagram of the profile of a joist used to show the number and location of the rows of bridging.Brittle FractureThe tearing or splitting of a member with little or no prior ductile deformation.BTU (British Thermal Unit)The amount of heat required to raise the temperature of one pound of water by one degree farenheit.Buckling LoadThe load at which a straight member under compression transfers to a deflected position.BuildingAny structure used for support or for shelter.Building CodeRegulations established by a recognized agency describing design loads, procedures, quality of materials, and construction details for buildings for the protection of the public.Building DesignerA registered architect or registered engineer who is responsible for the design of a structure. See Specifying Professional.Building OfficialThe officer or other authority which has the duty of administration and enforcement of a building code.Built-Up RoofA type of roof composed of two or more layers of alternating felt, tar and asphalt.Built-Up SectionA structural member made up from individual flat plates welded together or any structural metal elements that are welded or bolted together.

Butt PlateThe end plate of a structural member usually used to rest or butt against a like plate of another member in forming a connection.[Return to Glossary][C]

C ShapesA hot rolled shape called an American Standard Channel with symbol C.C SectionA structural member cold-formed from sheet steel in the shape of a block "C" which can be used by itself or back to back with another C Section.CADAbbreviation for Computer-Aided Drafting.CalipersA mechanical instrument usually having a pair of pivoted legs adjustable to any distance and used to measure thichness, distances between surfaces, and any internal or external diameter which is inaccessible with a scale.CamberCamber is an upward curvature of the chords of a joist or joist girder induced during shop fabrication to compensate for deflection due to loading conditions. Note, this is in addition to the pitch of the top chord.CanopyA projecting member that is supported at one end only.Cant StripA deck accessory which is a short piece of gage steel used at 45 degrees where a wall or parapet meets the end of deck.Canted SeatA seat which is sloped perpendicular to the member which most joist manufactures do not do. Usually the steel contractor furnishes a bent plate shim to provide level bearing for the seat.CantileverThe part of a member that extends freely over a support which is not supported at its end.Cap PlateA steel plate welded to the top of a column which a joist, joist girder, or other structural member can bear on.CatwalkSuspended structural framing used to provide access to and between areas below a roof and above a floor.Ceiling ExtensionIs similar to a bottom chord extension except that only one angle of the joist bottom chord is extended from the first bottom chord panel point towards the end of the joist.Centerline Span (or Center-to-Center)A theoretical span definition which is the distance between the actual centerlines of a beam, column, joist, or joist girder.CentroidThe point in a member at the intersection of two perpendicular axes so located that the moments of the areas on opposite sides of an axis about that axis is zero.Certified WelderA welder who has been certified by a competent experienced welding inspector or a recognized testing facility in the field of welding. The welder must be certified to make certain welds under qualified procedures. The welder must be qualified for each position, type weld, electrode, and thickness of base metal that is to be welded in the shop or field.Change OrderA written document which modifies the plans, specifications, or price of a construction contract.ChannelA hot rolled structural shape the looks like "[". There are American Standard Channels designated by (C) and Miscellaneous Channels designated by (MC).ChordThe two angle top or bottom member of a joist or joist girder, usually with a gap between the angles.CladdingThe exterior covering of the structural members of a building.Clear SpanThe actual clear distance or opening between supports for a structural member, i.e., the distance between walls or the distance between the edges of flanges of beams.ClevisA U-shaped yoke with internal threads in one end which can be attached to a threaded rod and the other end a connection with a hole used for a pin or bolt attchment.Clip Angle

A structural angle which attaches to the side of a wall, column, beam, etc. where a joist, joist girder, or other structural member bears.Closure StripA floor deck accessory made of gage metal which is placed over the ends of deck so that concrete cannot run out of the flutes of the deck.Coefficient of (Linear) ExpansionThe change in length, per unit, for a change of one degree of temperature.Cold-FormedThe process of forming a structural section by bending sheet or strip steel in roll-forming machines without the use of heat.Collateral LoadAll additional dead loads other than the weight of the building, such as sprinklers, pipes, ceilings, and mechanical or electrical components.ColumnIs a main vertical member carrying axial loads, which can be combined with bending and shear, from the main roof beams or girders to the foundation. These structural members carry loads parallel to its longitudinal axis.Column CurveA curve which shows the relationship between axial column strength and slenderness ratio.Compact SectionA steel section whose flanges must be continuously connected to the webs and the width-thickness ratios of its compression element can not exceed the limiting width-thichness ratios designated in the AISC Manual.Composite BeamA steel beam and a concrete slab connected, usually by shear stud connectors, so that they act together to resist the load on the beam.CompressionA condition caused by the action of squeezing or shortening of a component.Compression MemberAny member in which the primary stress is longitudinal compression.Concentrated LoadA single load or force that has such a small contact area as to be negligible compared with the entire surface area of the supporting member and applied at a certain point on the structure.ConnectionA joint connected by welds or bolts used to transmit forces between two or more members. See also Splice.ContinuityThe term given to a structural system denoting the transfer of loads and stresses from member to member as if there were no connections.Continuous SpanA span that extends over several supports and having more than two points.Continuous WeldA weld which extends continuously from one end of a joint to the other.ContractA legal document or agreement, enforceable by law, between two or more parties for the doing of something specified, such as the building of a building or furnishing materials.Contract DocumentsContract drawings, specifications, etc., used to build a structure which define the responsibilities of the parties involved.Contract DrawingsAll the architectural, structural, mechanical, electrical, etc. plans that make up a legal set of contract documents to build a building by.Conventional FramingFraming using conventional joist, beams, columns, masonry walls, etc. instead of framing used in Metal Building construction.CopingThe process of removing certain sections of a structural steel member to allow easier fitup to the supporting structural member.CorbelSuccessive courses of masonry projecting from the face of a wall to increase its thickness or to form a shelf or ledge for a structural member to bear on.Cover PlateA long plate usually welded to the top or bottom flange of a rolled steel beam or to the bottom chord of a joist or joist girder to increase the load carrying capacity of that member.CoverageThe width of a deck sheet, i.e., 30 inches or 36 inches.Crane

1) A machine used to move material by means of a hoist. 2) A machine that can usually move and is used to lift heavy materials or to lift members that are to be erected in a structure.CreepA time-dependent deformation of a structural member under a sustained constant load.CricketA ridge or drainage diverting roof framing.Crimped Angle WebA regular angel whose ends have been 'crimped' in the shape of a 'U' whose out-to-out distance is usually one inch. The actual crimped portion of the angle is only a few inches on each end and the end is inserted between top or bottom chord members to be welded.Critical LoadThe load at which deflection of a member or structure occurs as determined by stability analysis.CSI (Construction Specifications Institute)Abbreviation.CurbA raised edge of a concrete floor slab or support for a mechanical unit.Curtain WallA non-load bearing exterior wall which carries only its own weight and wind load.CurvatureThe rotation per unit length of a member due to bending forces.Cut-ListA list of components with dimensions used for fabrication and accounting purposes. See Bill of Materials.[Return to Glossary][D]

DampingFor floor vibrations, it is the rate of decay of amplitude.Dead LoadLoads due to the weight of the components making up the structure and that are intended to remain permanently in place.DeckA floor or roof covering made out of gage metal attached by welding or mechanical means to joists, beams, purlins, or other structural members and can be galvanized, painted, or unpainted.Deck TypeThe specific type of deck to be specified, such as Type "B" Wide Rib, Type "F" Intermediate, Type "N" Deep Rib, Type "A" Narrow Rib, Composite, Cellular, etc.DeflectionThe displacement of a structural member or system under load.DeformationThe act of distorting or changing the shape or dimensions of a structural element or body resulting from forces or stresses.Depth of JoistThe out-to-out distance from the top of the top chord to the bottom of the bottom chord taken a some reference location, usually at the midspan of the joist or joist girder.Design DocumentsThe plans, details, sections, specifications, etc. prepared by the building designer.Design LengthThe 'span' of a joist or joist girder in feet minus 0.3333 feet.Design LoadsThe loads specified in the contract drawings or specifications which a building is to be designed for.Design StrengthThe resistance provided by a structure, member, or connection to the forces imposed on it.Diagonal BracingStructural members which are inclined and are usually carrying axial load which enable a structural frame to behave as a truss to resist horizontal loads.Diagonal BridgingTwo angles or other structural shapes connected from the top chord of one joist to the bottom chord of the next joist to form an 'X' shape whose l/r ratio cannot exceed 200. The bridging members are almost always connected at their point of intersection.

DiaphragmRoof panel or decking, metal wall, or floor slab which provides a larger in-plane shear stiffness and strength adequate to transmit horizontal forces to the resisting structural system.Diaphragm ActionThe resistance to a racking affect or in-plane shear forces offered by roof deck, panels, or other structural members when properly attached to a structural frame.Double CurvatureWhen end moments on a structural member produce a bending effect which cause the member to form an S shape or has a reversal in curvature.Downstanding LegThe leg of a structural angle which is projecting down from you when viewing.DriftThe lateral movement or deflection of a structure.Drift IndexThe ratio of the lateral deflection to the height of the building.Drift PinA tapered pin used during the erection process to align holes in steel members which are to be connected by bolting.DuctAny tube, pipe or other conduit by which air or fluid is transfered.Duct OpeningThe round or square opening required through the web system of a joist or joist girder to allow passage of a duct.DuctilityIs the ability of a material to withstand large inelastic deformations without fracture. Structural steel has considerable ductility.Ductility FactorThe ratio of the total deformation at maximum load to the elastic-limit deformation.Dynamic LoadA load that varies with time which includes repeative loads, seismic loads, and other loads created by rapid movement.[Return to Glossary][E]

EaveThe line along the sidewall of a building formed by the intersection of the plane of the roof and the plane of the wall.Eave HeightThe vertical distance from finished floor to the eave.Eave StrutA structural member located at the eave of a building which supports a roof and/or wall panels.EccentricThe condition that exists when a load is applied on a line of action that does not pass through the centroid of the body it is applied to.EccentricityThe distance between a line of action of force and the centroid of the member it is applied to.Edge Angle1) A structural angle that is connected around the edge of a joist extension or other member 2) An angle used around the sides of a floor to contain the concrete when it is being poured which is also called a Pour Stop.Edge DistanceThe distance from the center of a hole to the edge of a connected part.Edge StripThe width or region around the edges of a building where uplift values are higher than in the interior of the roof.Effective DepthThe distance from the centroid of the top chord to the centroid of the bottom chord.Effective LengthThe equivalent length, KL, used in compression formulas. This method estimates the interaction effects of the total frame on a compression member by using K factors to equate the strength of a framed compression member of length L to an equivalent pin-ended member of length KL subject to axial load only.Effective Length Factor (K)

The ratio between the effective length and the unbraced length of a member measured between center of gravities of the bracing members. K values are given for several idealized conditions in which joint rotation and translation are realized.Effective Moment of InertiaThe moment of inertia of the cross section of a member that remains elastic when partial plastification takes place. See Moment of Inertia.Effective WidthThe transverse distance indicating the amount of slab that acts in conjuction with the supporting member.EJAbbrevbation for 'Expansion Joint'.Elastic AnalysisThe analysis of a member which assumes that material deformation disappears on removal of the force that produced it and the material returns to its original state.Elastic DesignSee Allowable Stress Design and Working Stress Design.ElectrodeThe device through which current is conducted thru to the arc or base metal during the process of welding.EmbedmentA steel member such as a plate, bolt, stud, or bar cast into a concrete structure which is used to transmit applied loads to the concrete.End BayThe bay which is located from the end of a building to the first interior main frame.End Diagonal or WebThe first web member on either end of a joist or joist girder which begins at the top chord at the seat and ends at the first bottom chord panel point.End DistanceThe horizontal distance from the first top chord panel point at the end of a joist to the first bottom chord panel point.End LapThe lap at the end of a sheet of deck which bears over the primary support (joist or beam).End MomentA moment which is generated at one end or both ends of a joist, joist girder, or beam due to continuous frame action which can be caused by wind, live load, or dead load moment.End PanelThe distance from the panel point at thejoist seat to the first top chord panel point towards the interior.End WallAn exterior wall which is perpendicular to the ridge of the building.EnvelopeA graphical plot indicating the maximum magnitude of an internal force effect such as flexual stess, shear stress, axial stress, torsional stress, etc. due to a series of load combinations.EODAbbreviation for 'Edge of Deck'.EOJAbbreviation for 'Edge of Joist'.EOSAbbreviation for 'Edge of Slab'.Equations of EquilibriumThe equations relating a state of static equilibrium of a member or structure when the resultant of all forces and moments are equal to zero. Three equations must be fulfilled simultaneously: Sum of the forces in the X-direction must equal zero, sum of the forces in the Y-direction must equal zero, and the sum of the moments about any point must equal zero for a two dimensional structure.Equivalent Uniform LoadA uniform load (in plf) derived from the maximum reaction (in lbs) or the maximum moment (in inch-lbs) of a member carrying various loads.Formula: Weq= 2 * max. reaction (in lbs) divided by length (in feet) orWeq=(8 * max. moment) divided by (lenght^2 (in feet) * 12)ErectionThe process of installing joists, joist girders, beams, bridging, deck, or other structural members in order to construct a structure.Erection PlanFloor or roof plans that identify individual marks, components, and accessories furnished by the joist manufactures in a detailed mannner to permit proper erection of the joist and joist girders. See Framing Plan and Placing Plan.Erector

The person or company that actually does the erecting of the joist or joist girders for a job.Expansion JointA break in construction or a special design detail to allow for thermal expansion and contraction of the materials of a structure.Extended EndThe extended part of a joist top chord with also the seat angles extended from the end of the jost extension back into the joist maintaining the standard 2 1/2 inch end bearing depth over the entire length of the extension.[Return to Glossary][F]

FabricationThe manufacturing process to convert raw materials into a finished product by cutting, punching, welding, cleaning, and painting.Factor of SafetyIs the ratio of the ultimate load for a member divided by the allowable load for a member and must always be greater than unity.Factored LoadThe product of the nominal load and a load factor.FarsideFor joists and joist girders, when looking at the member with the tagged end to the right, it is the side that is opposite the side you see first.FasciaThe flat surface located at the outer end of a roof overhang or cantilever end or also a decorative trim or panel which projects from the face of a wall.FastenerTerm for a connecting device such as a weld, bolt, rivet, etc.FCAbbreviation for 'Field Cut'.FieldA term used for the jobsite or building site where construction of the project will take place.Field WeldThe specific term used for the welding of structural members out at the actual jobsite and not in a fabricators shop.FillerA rod, plate, or angle welded between a two angle web member or between a top or bottom chord panel to tie them together usually located at the middle of the member. See Tie or Plug.FinishIn deck terminology, the coating on the deck sheet, i.e., galvanized, painted, or unpainted.Finish StripA roof deck accessory made out of gage metal for finishing out runs of deck for small areas of coverage where full sheet coverage is impractical.Fire ProofingThe process of coating a structural steel member with a fire retardant material to make the member resistant to fire.Fire-ResistanceThe ability of a joist or other structural member to resist a fire due to the type of protection it has, such as membrane protection or spray on protection. There are hundreds of floor-ceiling or roof-ceiling assemblies with their fire-resistance rating given in the Underwriters Laboratory Fire Directory.Fixed-End SupportA condition where no rotation or horizontal or vertical movement can occur at that end. This type of support has no degrees of freedom. Three reactive forces exist at the rigidly fixed end. See also Rigid Connection.FlangeThe projecting edge of a structural member.Flange BraceA structural bracing member used to provide lateral support to the flange of a beam, the bottom chord or a joist girder, or a column.FlashingPieces of sheet metal or the like used to cover and protect joints, etc. where a roof comes in contact with a wall or chimney.FluteThe fold or bend in a sheet of deck which forms a groove or furrow.FMS (Factory Mutual System)A leader in property loss prevention engineering and adjustment. It helps companies prevent and control property loss through research, engineering, and education.

Folding PartitionA moveable wall on a track suspended from a joist or beam which usually folds like an accordion and can be stored in a closet or pocket in a wall.FootingA concrete pad or mat located under a column, wall, or other structural member that distributes loads from that member into the supporting soil.FoundationThe substructure which supports a building or other structure.FrameA structural framing system consisting of members joined together with moment or rigid connections which maintain their original angular relationship under load without the need for bracing in its plane. See Rigid Frame.Framed OpeningHeaders or other structural members which surround an opening in a roof which can be for mechanical units, straiwells, etc.Framing PlanFloor or roof plans that identify individual marks, components, and accessories furnished by the joist manufactures in a detailed mannner to permit proper erection of the joist and joist girders. See Erection Plan and Placing Plan.Free-Body DiagramA diagram on which all of the external forces acting on a body are shown at their respective points of application.FrequencyA measure of floor vibration. It is the speed of the oscillations of vibration and is expressed in cycles per secong or Hz (Hertz).[Return to Glossary][G]

G-Type Joist GirderA type of Joist Girder where joists are located at panel points where diagonal webs intersect the top chord only.GableThe triangular portion of a roof located above the elevation of the eave line of a double sloped roof.Gable JoistA non-standard type of joist where the top chord is double pitched at an extreme pitch (say 3/12) and the bottom chord is straight or level.Gage1) The thickness of a sheet of deck or 2) The distance from centerline hole to centerline hole across a set of holes, usually perpendicular to the joist or joist girder.GalvanizedThe process of coating steel with zinc for corrosion resistance.GambrelA roof having two slopes on each side, the lower slope usually steeper than the upper one.GirderA main horizontal, primary structural member spanning between two main supports which carries other members or vertical loads.GirtA horizontal structural member that is attached to the sidewall or endwall columns supporting sheeting or paneling.GradeThe ground elevation around a building.Grillage BeamA short beam used like a bearing plate to distribute large reactive loads to a wall such as the load from a joist girder.Gusset PlateA steel plate used to connect structural steel members or to reinforce members. It is usually inserted between the top or bottom chord of a joist or joist girder.[Return to Glossary][H]

H-Series JoistA series of joist adopted in 1961 so proportioned that the allowable tension or bending stress does not exceed 22,000 psi or 30,000 psi depending on whether 36 ksi or 50 ksi yield steel was used.HardnessIs a measure of the resistance of a material to scratching and indention.

HeaderA structural member located between two joists or between a joist and a wall which carries another joist or joists. Usually made up of an angle, channel, or beam with saddle angle connections on each end for bearing.HeelThe outside point of a structural angle where the two perpendicular legs intersect.High Strength BoltsA structural steel bolt having a tensile strength greater than 100,000 pounds per square inch, usually A325 or A490.High Strength SteelStructural steel having a yield stress greater than 36,000 pounds per square inch.Hinge SupportThis type of support has one degree of freedom, it can freely rotate about its axis but it cannot displace in any direction. Two mutually perpendicular reactive forces exist at the hinge and their lines of action pass through the center of the hinge. See Pin Connection or Support.Hip RoofA roof which slopes from all four sides of a building. The line where two adjacent sloping sides intersect is called the 'hip'.Hip and ValleyA system of roof framing where support members form valleys and ridges.HoistA chain or electric lifting device usually attached to a trolly which travels along a monorail or bridge crane.Homogeneous MaterialA material having the same engineering design properties throughout.Hooke's LawThe linear relationship of forces and deformations, or stresses and strains.Horizontal BridgingA continuous angle or other structural shape connected to the top and bottom chord of a joist horizontally whose l/r ratio cannot exceed 300.Horizontal Shear StressIs zero at the outer fibers of a section and is maximum at the neutral axis. It tends to cause one part of the section to slide past the other.Formula: Horizontal Shear stress (in psi)=(V * Q)/I*t, where 'V' is the external vertical shear on the section in lbs, 'I' is the moment of inertia of the section in inches^4, 'Q' is the statical moment about the neutral axis of the entire section of that portion of the cross-section lying outside of the cutting plane and 't' is the width at the cutting plane.Hot-Rolled ShapesStructural steel sections which are formed by rolling mills from molten steel which can be angles, channels, W Shapes, S Shapes, etc.HP ShapesA hot rolled shape with symbol HP used for bearing piles which have essentially parallel flanges and equal web and flange thickness.HysteresisA term that describes the behavior of a structural member subjected to reversed, repeated load into the inelastic range whose plot of load verses displacement is characterized by loops. The amount of energy dissipated during inelastic loading is indicated by the enclosed area within these loops.[Return to Glossary][I]

ICBO (International Conference of Building Officials (Uniform Building Code)A minimum model regulatory code dedicated to public safety through development and promotion of uniform codes and standards.Ice DamA dam or blockage formed on a roof by the buildup of ice along the eave of a building.IFI (Industrial Fasteners Institute)Abbrreviation.III (Institute of the Ironworking IndustryAbbreviation.Impact FactorThe factor by which the static weight is increased by dynamic application.Impact LoadA weight that is dropped or a dynamic load generated by movement of a live load such as vehicles, craneways, etc.Impact StrengthThe ability of a material to absorb the energy of a load delivered rapidly to a member.

Impact WrenchA pneumatic device used to tighten nuts on bolts.InclusionsNonmetallic material which is entrapped in sound metal.Inelastic ActionDeformation of a material which does not disappear when the force that produced it is removed.Inflection PointRepresent a point of zero moment in structural member.Influence LineAn influence line is a curve whose ordinates give the values of some particular function (shear, moment, reaction, etc.) in an element due to a unit load acting at the point corresponding to the particular ordinate being considered. Influence lines for statically determinate structures are straight lines and for statically indeterminate structures the lines are curved and their construction involves considerable analysis.InstabilityA condition reached when a structure or structural member is loaded in which continued deformation results in a decrease in its load-resisting capacity.InsulationAny material used to reduce heat transfer in a roof or building.Intermittent WeldA weld which is not continuous. It is broken by recurring unwelded spaces.Internal PressureThe pressure inside a building which is a function of the wind velocity and the number and locations of openings.Interior BearingBearing supports which are interior to two exterior supports.ISO 9000 (International Organization for Standardization)Is a series of quality management and assurance standards for companies to strive for.IsotropicA material having equal physical properties along all axes.[Return to Glossary][J]

J-Series JoistA series of joist adopted in 1961 so proportioned that the allowable tension or bending stress does not exceed 22,000 psi and was made from A36 steel.Jack TrussA joist girder that is supporting another joist girder.JBEAbbreviation for 'Joist Bearing Elevation'.Jib CraneA cantilevered boom or beam with a hoist and trolly used to pick up loads in all or part of a circle around which it is attachedJigA device which holds work or pieces of materal in a certain position until rigidly fastened or welded during the fabrication process.JobsiteThe specific location where a structure is being build.JointThe area where two or more ends or surfaces are joined by a weld or other fastener. See Panel Point.Joint PenetrationThe minimum depth the weld metal extends from its face into a joint.JoistA structural load-carrying member with an open web system which supports floors and roofs utilizing hot-rolled or cold-formed steel and is designed as a simple span member.Joist DesignationA standard way of communicating the joist safe uniformly distributed load-carrying capacities for a given span such as 16K5 or 24K10 where the first number is the nominal joist depth at midspan and the last number is the chord size. See Longspan Designation and Joist Girder Designation.Joist Girder

A primary structural load-carrying member with an open web system designed as a simple span supporting equally spaced concentrated loads of a floor or roof system acting at the panel points of the joist girder and utilizing hot-rolled or cold-formed steel.Joist Girder DesignationA standard way of communicating the girder design loads such as 48G6N10.5K where the first number is the nominal girder depth at midspan, 6N is the number of joist spaces on the span of girder, and 10.5K is the kip load on each panel point of the girder. The approximate dead load weight of the member is included in the kip load. See Joist Designation and Longspan Designation.Joist ManufacturerThe producer of joists or joist girders who is SJI approved.Joist SpacingThe distance from one joist to another.Joist SubstituteA structural member which is intended for use at very short spans (10 feet or less) where open web steel joists are impractical. They are usually used for short spans in skewed bays, over corridors, or for outriggers. It can be made up of two or four angles to form channel sections or box sections. See Angle Unit.[Return to Glossary][K]

K-DistanceThe distance from the outside fiber of a rolled steel beam to the web toe of the fillet of a rolled shape.K-Series JoistA series of joist adopted in 1986 based on a load/span type of determination.KCS JoistIs a K-Series joist that is designed to support uniform load plus concentrated loads or other non-uniform loads.KerfThe width of a cut produced during a cutting process.Key PlanA small reference plan or outline of the whole building on each plan sheet divided into smaller areas for which each sheet is drawn. It can also show different sequences, phases, sheet number that area is drawn on, etc.KickerA structural member used to brace a joist or beam usually at an angle.KiloSI prefix for 10^3 or 1000.KipA unit of weight equal to 1000 pounds.Knee BraceA structural brace positioned diagonally between a beam or column and a joist panel point.Knife Plate SeatA vertical plate used as a joist seat whose width is small for bearing purposes. It is used for hip and valley bearing conditions, canted seat conditions, and extreme skewed conditions.KSI (Kips per Linear Foot)Is 1000 pounds per square inch.KSF (Kips per Square Foot)Is 1000 kips per square foot.[Return to Glossary][L]

Lamellar TearingIs a separation or crack in the base metal caused by through-thickness weld shrinkage strains of adjacent weld metal.Lap JointLateral BucklingAlso called lateral-torsional buckling. This is buckling of a member involving lateral deflection and twist.Lateral BracingMembers, fasteners, or welds which brace a member at certain locations to prevent lateral movement.Lean-ToA structure depending upon another structure for support and having only one slope such as a shed.

LeewardThe direction toward which the wind is blowing, which is opposite the side from which the wind blows. Opposite of windward.LegThe flat projecting part of a structural angle.Leveling PlateA steel plate used on top of a foundation on which a structural column can be placed.LintelA horizontal structural member spanning a door, window, or other wall opening which supports a wall or any construction immediately above.Live LoadLoads on a member that are not permanent and are likely to be moved at some point in the life of the structure. They can be loads produced by the use and occupancy of the building. These loads do not include dead load, wind load, snow load, or seismic load.LoadAn external force or other action acting on a member or structure. It can be from permanent construction, environmental effects, differential settlement, occupants, and material objects.Load CombinationThe combination of loads which produce the worse loading condition in a structural member.Load TableA table of standard joist designations which give the total safe uniformly distributed load-carrying capacities and live load-carring capacities of the joists for different span lengths. The table also gives the approximate weight per foot of each joist designation.Loading DiagramA diagram which shows all design loads and design criteria that a member is to be designed for. The loads include: dead load, live load, snow drift, concentrated loads, moments, etc. The design criteria include: deflection requirements, load combinations, net uplift, one-third increase in allowable stress allowed or not, etc.LongitudinalThe direction extending along the long axis of the member.Longspan DesignationA standard way of communicating the longspan joist safe uniformly distributed load-carrying capacities for a given clear span such as 18LH06 or 36LH10 where the first number is the nominal joist depth at midspan and the last number is the section number. See Joist Designation and Joist Girder Designation.Longspan JoistA structural load-carrying member with an open web system which supports floors and roofs utilizing hot-rolled or cold-formed steel and is designed as a simple span member. These carry higher loads than a regular joist.Loose Angle StrutA single or double angle either welded or bolted at the first bottom chord panel point and extended to brace another member such as a beam, joist girder, frame, or wall.LRFD (Load and Resistance Factor Design)A method of proportioning structural members such that no limit state is exceeded when all appropriate load combinations have been applied.[Return to Glossary][M]

M ShapesA hot rolled shape called a Miscellaneous Shape with symbol M that cannot be identified as W, HP, or S Shapes.Major AxisThe axis of a structural member possessing the largest section modulus and radius of gyration, thus having the greatest flexural and axial compressive strength.MarkAn identification number or method of relating to the erector which joist, joist girder or other separate part of the building goes at what location when being erected, i.e., J1, K25, L7, G12, or JG9. See Piece Mark and Part Number.MasonryA type of construction from materials such as concrete blocks, bricks, concrete, stone, or ceramic blocks which is laid unit by unit and set in mortar.Maxwell DiagramA graphical method of determining stresses in a truss by combining force polygons of all the joints into one stress diagram.MBMA (Metal Building Manufacturers Association)An association of manufacturers of metal building systems whose objectives are to compile and publish recommended design standards which will insure high quality metal buildings.MC ShapesA hot rolled shape called a Miscellaneous Channel with symbol MC.Mechanical UnitAn air conditioner or other unit either placed on top of a roof system or hung below which applies loads to joist or joist girders.Mega

SI Prefix for 10^6 or 1000000.Member ReleaseAn idealization to model how members are attached to "each other". It designates whether forces and moments at the ends of a member are considered fixed to or released from the member's point of attachment.Metal Building SystemA building system consisting of a group of coordinated components which have been designed for a certain loading. These components are mass produced and assembled in various combinations with other structural materials to produce a building.Metal StudA structural steel member used for framing walls just as a regular wooden one.Meuller-Breslau PrincipleIs a simple method to draw approximate shapes of influence lines.MezzanineA low floor between two stories in a building, usually just above the ground floor.MHI (Material Handling Industry)Is a not-for-profit organization which was formed to advance the interests of the material handling industry which includes the movement, storage, control, and protection of material and products throughout the process of their manufacture, distribution, consumption, and disposal.MilA measurement of thickness of paint. One mil=.001 of an inch.MilledA surface which has been accurately sawed or finised to a true plane.Mill Test ReportA report of a heat of steel that indicates the customer's order number, grade of steel, number and dimensions of pieces shipped, and the chemical compositional makeup of hot rolled structural steel members. It also indicates physical properties, such as, yield strength, tensile strength, elongation, impact, and ultimate strength.MilliSI prefix for 10^-3 or 0.001Minor AxisThe axis of a structural member possessing the smallest section modulus and radius of gyration, thus having the least flexural and axial compressive strength.Miter CutA single cut made at an angle to the member length. See Bevel Cut.Modulus of Elasticity (E)Is the slope of the straight-line portion of the stress-strain curve in the elastic range found by dividing the unit stress in ksi by the unit strain in in/in. For all structural steels, the value is usually taken as 29,000 ksi. This is also called Young's Modulus.MomentThe tendency of a force to cause a rotation about a point or axis which in turn produces bending stresses.Moment ConnectionA connection designed to transfer moment as well as axial and shear forces between connecting members.Moment DiagramA diagram that represents graphically the moment at every point along the length of a member.Moment of Inertia (I)A physical property of a member which helps define rigidity or stiffness and is expressed in inches raised to the fourth power. It is a measure of the resistance to rotation offered by a section's geometry and size.Moment PlateA welded steel plate used to develop a rigid connection to the supporting member so that moment transfer can occur.MonorailUsually a single rail support for a material handling system.MPC (Materials Properties Council)Abbreviation.MTA hot rolled structural tee shape with symbol MT which is cut or split from M Shapes.MullionA vertial member or division between the panels of a window.MylarA type of strong, thin polyester sheet used for producing blueprints of architectural drawings.[Return to Glossary]

[N]

NailersStrips of lumber attached to the top chord of a joist so plywood or other flooring can be nailed at 36 inches maximum on center.NBC (National Building Code)A minimum model regulatory code for the protection of public health, safety, welfare and property by regulating and controlling the design, construction, quality of materials, use, occupancy, location and maintenance of all buildings and structures within a jurisdiction.NBS (National Bureau of Standards)Abbreviation.NCEES (National Council of Examiners for Engineering and Surveying)Provides leadership in professional licensure of engineers and land surveyors.NEA (National Erectors Association)Abbreviation.NearsideFor joists and joist girders, when looking at the member with the tagged end to the right, it is the side you see first and is closest to you.Neutral AxisThe surface in a member where the stresses change from compression to tension, i.e., represents zero strain and therefore zero stress. The neutral axis is perpendicular to the line of applied force.NewtonThe SI unit of measure for force (N).NFPA (National Fire Protection Association)An international nonprofit organization to reduce the burden of fire on the quality of life by proposing codes and standards, research, and education on fire related issues.NICAbbreviation for 'Not in Contract'.NIST (National Institute of Standards and Technololgy)An organization that works with industry and government to advance measurement science and develop standards.Non-Bearing WallA wall that supports no vertical load other than its own weight.Noncompact SectionA steel section which does not qualify as a compact section and the width-thickness ratios of its compression elements do not exceed the values designated in the AISC Manual.Nonrigid StructureA structure which cannot maintain its shape and may undergo large displacements and would collapse under its own weight when not supported externally.NRCA (National Roofing Contractors Association)Abbreviation.NSPE (National Society of Professional Engineers)Abreviation.NTSAbbreviation for 'Not to Scale'.[Return to Glossary][O]

Offset RidgeWhen the ridge of a joist that has the top chord pitched two ways is not in the center of the member or bay.On The FlatA measurement of distance horizontally on a plan, no slopes involved.One-third IncreaseWhen designing steel members for forces produced by wind or seismic conditions, the allowable stresses in the design formulas may be increased 1/3 above the values otherwise provided.OSHA (Occupational Safety and Health Administration)A federal organization whose purpose is to save lives, prevent injuries, and protect the health of the workers of America.Outrigger

A structural member which is usually perpendicular to a joist and attaches under the outstanding leg of one of the joist top chord angles. It then bears on a beam or wall and cantilevers across, similar to a top chord extension.Outstanding LegThe leg of a structural angle which is projecting toward or away from you when viewing.OverhangThe extension of the top chord of a joist beyond the outside of the bearing support. See Top Chord Extension.[Return to Glossary][P]

P-Delta EffectThe secondary effect of column axial loads and lateral deflection on the moments in structural members.Pack OutWhen joists are erected in multiple bays, they begin to hit each other end to end (or pack out) because the center to center of beam is not true or the joists are to long.Panel or Panel Length1) The distance between two adjacent panel points of a joist or joist girder 2) A sheet of deck for a roof or floor.Panel PointThe point where one or more web members intersect the top or bottom chords of a joist or joist girder. See Joint.Parallel ChordType of joist or joist girder which has its top and bottom chords parallel to each other. The member can be sloped and still have parallel chords.ParapetThe portion of a vertical wall of a building which extends above the roof line at the intersection of the wall and roof.Part NumberSee Mark and Piece Mark.Partially RestrainedA type of connection that displays a moment rotation behavior that can neither be described as pinned nor fixed.PartitionA wall that is one story or less in height used to subdivide the interior space in a building and can be a bearing wall or a non-bearing wall.PascalThe SI unit of measure for stress or force per unit area (N/m^2).PEAbbreviation for 'Professional Engineer'.PeakThe highest point of a gable or also the highest point on a joist or joist girder where the sloped chords meet. See also Apex.PenthouseA small enclosed structure above the roof of a building.PermitAn official document or certificate by a governmental agency or building official authorizing performance of a building process or other specified activity.Piece MarkSee Mark and Part Number.PilasterA reinforced or enlarged portion of a masonry wall to provide support for vertical roof loads or lateral loads on the wall.Pin Connection or SupportA connection where no moment is transfered from one member to another, only axial and shear forces. This type of support has one degree of freedom, it can freely rotate about its axis but it cannot displace in any direction. Two mutually perpendicular reactive forces exist at the pin and their lines of action pass through the center of the pin. See Hinge Support.PipeA hollow cylinder of metal used for the conveyance of water or gas or used as a structural column which comes in sizes of standard, extra strong and double-extra strong.Pipe BridgeA structural system where two joists are used to carry loads such as piping or ducts. The two joists have to have diagonal bridging and their top and bottom chords have to be laced together with structural members to provide stability for the whole structure,PitchIs the slope or inclination of a member. It is defined as the ratio of the total rise to the total width. It also is defined as the angle that the top chord makes with the lower chord. There can be single or double pitched members.

Placing PlanSee Erection Plan and Framing Plan.Plan NorthThe North arrow symbol on a contract drawing usually 90 degrees to the longitudinal axis of the plan so that communication will be easier for the elevations of the building, sections, etc.Plane FrameA two-dimensional structural framework.Plastic DesignA design concept based on multiplying the actual design loads by a suitable load factor and then using the yield stress as the maximum stress in any member.PlateA thin, flat piece of metal of uniform thickness usually over 8 inches to 48 inches in width.Plate GirderA built-up structural beam.PLF (Pounds per Linear Foot)A unit of load obtained by multiplying pounds per square foot times the tribituary width on a joist.PlugA rod, plate, or angle welded between a two angle web member or between a top or bottom chord panel to tie them together usually located at the middle of the member. See Tie or Filler.Plug WeldA weld in a slot in a piece of steel which overlaps another piece. A principle use for a plug weld is to transmit shear in a lap joint. See Slot Weld and Puddle Weld.Poisson's RatioDefined as the ratio of the unit lateral strain to the unit longitudinal strain. It is constant for a material within the elastic range. For structural steel, the value is usually taken as 0.3. It gradually increases beyond the proportional limit, approaching 0.5.Polar Moment of Inertia (J)Is the sum of any two moments of inertia about axes at right angles to each other. It is taken about an axis which is perpendicular to the plane of the other two axes.PondingThe gathering of water at low or irregular areas on a roof.Portal FrameA rigid frame structure which is designed to resist longitudial loads where diagonal bracing is not permitted. It has rigidity and stability in its plane.Pounds (LB or #)A unit of weight.Pour StopAn angle used around the sides of a floor to contain the concrete when it is being poured.Powder ActuatedA fastening method which uses a powdered charge to imbed the fastener into the member.PrefabricateTo manufacture or construct parts or sections of structural assemblies beforehand that are ready for quick assembly and erection at a jobsite.Press BrakeA machine used in cold-forming metal sheet or strip into a desired cross section or structural shape.Primary MembersThis is the main load carrying members of a structure such as a beam or joist girder.Principle of SuperpositionStates that the resultant is the algebraic sum of the effects when applied separately.Primer or PaintThe initial coating of a member applied in the shop which is not a finish coat and only protects from rust for a limited time.Prismatic BeamA beam with uniform cross section.Profile DrawingA drawing or diagram which shows the outline of a joist with dimensions and also maybe the web system configuration and bridging rows. See Side-View DiagramProportional LimitThe point on a stress-strain curve where the linear relationship between stress and strain ends and usually coincides with the material yield point.

PSI (Pounds per Square Inch)A unit of stress or pressure.PSF (Pounds per Square Foot)A unit of stress which to multiply the tribituary width on a joist by to get PLF.Puddle WeldSee Plug Weld.PurlinUsually a cold-formed horizontal structural member attached perpendicular to the joist top chord or main frames of a building for support of the roof deck.[Return to Glossary][Q]

****No terms yet![Return to Glossary][R]

Radius of Gyration (r)Is the distance from the neutral axis of a section to an imaginary point at which the whole area of the section could be concentrated and still have the same moment of inertia.Formula: The square root of (the moment of inertia in inches^4 divided by the area of the section in inches^2) expressed in inches.RafterThe main beam supporting a roof system or a sloping roof framing member.RakeThe edge of a roof which intersects the gable part of a roof.RCSC (Research Council on Structural Connections)Abbreviation.ReactionThe force or moment developed at the points of a support.RedundantsThe reactions which are not necessary for static equilibrium.ReinforcementAn additional member added to a structural member to provide additional strength.ReinforcingThe process of strengthening a member with some additional piece of material.RelaxationIs a decrease in load or stress of a member under a sustained constant deformation.RepairThe reconstruction or renewal of any part of an existing structure or building for the purpose of its maintenance.Residual StressPre induced stresses within a structural member due to uneven cooling of the shape after hot-rolling.ResistanceThe capacity of a structure or structural member to resist the effects of loads or forces imposed on it.Retaining WallA wall designed to resist the lateral displacement of soil, water, or any other type of material.RibA fabricated fold or bend in a sheet of deck which projects up from a horizontal plane.RidgeThe highest point on the roof of a building formed by two intersecting slopes or the horizontal line made by the top surfaces of the two intersecting sloping roof surfaces.Rigid Connection

A connection where moment is transfered from one member to another. See also Fixed-End Support.Rigid Frame or StructureA structural framing system consisting of members joined together with moment or rigid connections which maintain their original angular relationship under load without the need for bracing in its plane. See Frame and Stability.RiseThe vertical distance from the bottom to the top of an entity.RMI (Rack Manufacturers Institute)An institute organized in 1958 by industry leaders as a not-for-profit trade association. Its mission is to advance standards, quality, safety, and general fitness for intended use of industrial steel storage rack systems.RodA smooth solid round bar used for the web system of a bar joist.Roof CoveringThe exposed exterior roof skin of a building which can be sheets, panels or other materials.Roof OverhangA roof extension that projects beyond the ends or sides of a building.Roller SupportThis type of support has two degrees of freedom, it can freely rotate about its axis or displace in one direction in the plane. Only one reactive force exists at a roller which acts perpendicular to the path of the displacement and its line of action passes through the center of the roller.[Return to Glossary][S]

S ShapesA hot rolled shape called an American Standard Beam with symbol S.Saddle AngleThe angle connection or seat on the end of a header or frame which bears from the side on the top chord of a joist. This angle should be designed to carry the reaction of the header or frame to the center of the joist and must rest on and weld to both top chord angles.Sag RodA tension member used to limit the deflection of a girt or purlin in the direction of the weak axis.SBC (Standard Building Code)A minimum model regulatory code for the protection of public health, safety, welfare and property by regulating and controlling the design, construction, quality of materials, use, occupancy, location and maintenance of all buildings and structures within a jurisdiction.Scab OnA member fastened or welded to another member for reinforcement.Scissor JoistA non-standard type of joist where both the top chord and bottom chord are double pitched and parallel with each other.ScupperAny opening or drain in the side of a structure, flat roof, or downspout for the drainage of rain water.ScuttleA framed opening in a roof used for access to the roof from inside a building.SDI (Steel Deck Institute)An institute which brings uniformity to the design, manufacture, quality control, and construction practices applicable to cold-formed steel deck.SEAA (Steel Erectors Association of America)An organization that sets uniform standards among the many steel erectors and helps promote safety in the erection industry.Seat DepthThe out-to-out depth of the end bearing shoe or seat of a joist or joist girder which is the distance from the top of the top chord to the bottom of the bearing seat angle or plate.Section Modulus (S)A physical property of strength of a structural member. It relates bending moment and maximum bending stress within the elastic range. Formula: S=I/c where 'I' is the moment of inertia of the cross-section about the neutral axis in inches^4 and 'c' is the distance from the neutal axis to the outermost fibers.Seimic LoadAre assumed lateral forces acting in any horizontal direction that produce stresses or deformations in a structural member due to the dynamic action of an earthquake.Self Tapping ScrewA mechanical fastener for attaching deck, panels, or other materials to a structure which taps its own threads in a predrilled hole.SequenceA breakdown of when materials are to be made or delivered for a project with one following after the other.

Set BackThe distance from the outside edge of an angle or other member to the edge of a gusset plate or angle welded near the end.ShaftAn interior space, enclosed by walls, which extends through one or more stories or basement which connects successive floors and/or roof for elevators, dumbwaiters, mechanical equipment, etc.Shape FactorThe ratio of the plastic section modulus Z to the elastic section modulus S or the ratio of the plastic moment Mp to the yield moment My.ShearA condition or force causing two contacting parts of a material to slide past each other in opposite directions parallel to their plane of contact.Shear CenterThe point in a cross section of a structural member to which a load may be applied and not induce any torsional stress in the cross section.Shear DiagramA diagram that represents graphically the shear at every point along the length of a member.Shear ReleaseA boundary condition which constrains a member end from axial displacement and rotation but allows movement in a direction perpendicular to the members longitudinal axis.Shear Stud ConnectorA steel device used in composite design which is welded to the top flange of a beam or top chord of a joist which transfers shear from a concrete slab to the supporting member.Shear WallA wall that resists horizontal shear forces applied in the plane of the wall.ShimA piece of steel used to level a joist seat. It can be a bent plate, flat plate or rod.Shipping ListA list that gives each part or mark number, quantity, length of material, total weight, or other description of each piece of material to be shipped to a jobsite. See also Bill of Ladding.Shop Drawings1) Can also be called the erection plans or framing plans 2) The actual drawings used by a shop to fabricate a product which includes all dimensions, materials, tolerances, etc.ShoreThe process of temporarily supporting a structure or structural member with auxiliary members.SI (Le Systeme International d'Unites)The international abbreviation for the International System of Units or metric system.Side LapThe lap at the sides of a sheet of deck and is attached by side lap screws or welds between supports.Side Lap ScrewsA screw used to connect the sides of two adjacent sheets of deck together, #10 being the standard size.Side-View DiagramA drawing or diagram which shows the outline of a joist with dimensions and also maybe the web system configuration and bridging rows. See Profile Drawing.Side WallAn exterior wall which is parallel to the ridge of the building.SideswayThe lateral movement of a structure when subjected to lateral loads or unsymmetrical vertical loads.Simple or Single SpanA span with supports at each end, no intermediate support, that restrain only against vertical displacement with the ends of the member being free to rotate.Single CurvatureWhen moments produce a deformed or bent shape of a structural member having a smooth continuous curve or arc.Single SlopeA sloping roof in one plane which slopes from one wall to the opposite wall.Single-Ply RoofA type of roofing system using thermoplastic membranes which are seamed by either hot air or solvent welding of one sheet to the next or using thermoset membranes which are seamed with an adhesive.SJI (Steel Joist Institute)The institute is a non-profit organization of active joist manufacturers that maintains sound engineering practice throughout the joist industry. The institute coopera Wtes with business and government agencies to establish steel joist standards and does continuing research of their products to maintain the integrity of their products.

SkewThe condition when two entities come together at an angle which is not 90 degrees or perpendicular to each other.SkylightAn opening or roof accessory in a roof or ceiling for admitting light. If it bears across a joist, the top chord angles may be unbraced for design considerations.SlagA non-metallic byproduct of the welding process forming a hard crust over the molten steel which should be chipped away for inspection of a weld.Slender Element SectionA steel section whose width-thickness ratios of any compression element exceeds the values of a noncompact section.Slenderness RatioThe ratio of the effective length of a column to the radius of gyration of the column about the same axis of bending.Slip-Critical JointA bolted joint in which the slip resistance of the connection is required.SlopeThe angle or inclination a structural member makes with reference to a horizontal position expressed in inches of vertical rise per 12 inches of horizontal run, i.e. 3/12.Slot LengthThe length of a slotted hole in a joist bearing seat or other structural connection.Slot WeldSee Plug Weld.Snow DriftThe triangular accumulation of snow at high/low areas of structures expressed in PSF or PLF.Snow LoadAre forces applied to a member by snow accumulation on the roof of a structure.SoffitA panel which covers the underside of an overhang, cantilever end, or mansard.Soil PressureThe load per unit area that a structure exerts through its foundation on the underlying soil.SpanThe distance between supports which is the centerline of a beam, column, or joist girder or 4 inches onto a wall.Spandrel Joist or BeamA structural member at the outside wall of a building, supporting part of the floor or roof and possibly the wall above.Special DesignA design required by a loading diagram or other special notes because a standard joist or joist girder cannot be specified from a load table.SpecificationThe detailed description of requirements, materials, dimensions, etc. of a proposed building or project.Specifying ProfessionalAn architect or engineer, registered or licensed to practice professional architecture or engineering, as defined by the statutory requirements of the professional registration laws. See Building Designer.SpliceThe connection between two chord members or other structural members joined at their ends by welding or bolting to form a single, longer member.Sprinkler SystemA system for fire protection usually consisting of overhead piping connected to a water supply to which automatic sprinklers are attached that discharges water in a specific pattern for extinguishment or control of a fire.SquareIn deck terminology, it is the term for 100 square feet of deck or roofing surface.Formula: number of squares = sum of(length of deck sheet in feet * width of deck sheet in feet * number of pieces)divided by 100.Square CutA cut to a structural member made at 90 degrees to the length of the member.SRI (Steel Recycling Institute)Abbreviation.SSPC (Steel Structures Painting Council)

A professional technical society whose primary objective is to improve the technology and practice of prolonging the life of steel and concrete structures through the use of protective coatings.SSR (Standing Seam Roof)A type of roof system where the deck is attached to clips which are then attached to the beam or joist. Usually this type of roof system cannot be counted on to provide lateral stability or support to the joist top chord.SSRC (Structural Stability Research Council)Abbreviation.STA hot rolled structural tee shape with symbol ST which is cut or split from S Shapes.StabilityThe property of a body to maintain its shape and remain rigid when detached from its support. Also see Rigid Frame or Structure.Stabilizer PlateA steel plate at a column or wall inserted between the end of a bottom chord of a joist or joist girder to weld the bottom chord to or to restrain the bottom chord from lateral movement.Starter JoistA joist which is spaced close to a wall for deck support, usually 6 inches.Static EquilibriumA member or body that is initally at rest and remains at rest when acted upon by a system of forces.Static LoadA load applied slowly and then remains nearly constant.Statically DeterminateA member or structure that can be analyzed and the reactions and forces determined from the equations of equilibrium.Statically IndeterminateA member or structure that cannot be analyzed soley by the equations of statics. It contains unknowns in excess of the number of equilibrium equations available. Additional equations must be written based on a knowledge of elastic deformations.StiffenerA member used to strengthen another member against buckling or to distribute load or to transfer shear. Usually a flat bar, plate, or angle welded perpendicular to the longitudinal axis of the member.StiffnessThe resistance to deformation of a structural member which can be measured by the ratio of the applied force to the corresponding displacement.StoryThat portion of a building which is between the upper surface of any floor and the upper surface of the floor next above.Story DriftThe difference in horizontal deflection at the top and bottom of a story.Strain HardeningThe condition when ductile steel exhibits the capacity to resist additional load than that which caused initial yielding after undergoing deformation at or just above the yield point.StressAn internal force that resists a load. It is the intensity of force per unit of area, i.e., psi (pounds per square inch).Stress ConcentrationA localized stress which is considerably higher than average due to sudden changes in loading or sudden changes in geometry.StringerIn buildings, a structural member supporting stair steps.Strong AxisThe cross section which has the major principal axis.StructureA mechanism designed and built or constructed of various parts jointed together in some definite manner to carry loads and resist forces.Structural SteelsA large number of steels that are suitable for load-carrying members in a variety of structures because of strength, economy, ductility, and other properties. Strength levels are obtained by varying the chemical composition and by heat treatment.StrutA structural member used as a brace to resist axial forces.StudA wood or metal vertical wall member to which exterior or interior covering material may be attached. It can be either load bearing or non-load bearing.Suction

A partial vacuum due to wind loads on a building which cause a load in the outward direction.Sump PanA metal deck accessory used at drain locations to close the opening where holes are cut in the metal deck.Superimposed LoadUsually means a load that is in addition to the dead weight of the bar joists and bridging.SweepThe curvature of a structural member in the perpendicular transverse direction of its vertical axis.[Return to Glossary][T]

Tagged End (T.E.)This is the end of a joist or joist girder where an identification or piece mark is shown by a metal tag. The member must be erected with this tagged end in the same position as the tagged end noted on the erection plan.Tangent ModulusThe slope of the stress-strain curve of a material in the inelastic range at any given stress level.TeeA hot rolled shape with symbol T and is shaped like a "T".Tempory StructureAnything which is built which will not become part of the permanent structural system and will eventually be removed before or after the completion of the structure.Tensile StrengthThe longitudinal pulling stress a material can withstand without tearing apart or the maximum tensile stress the material can sustain.TensionA condition caused by the action of stretching or pulling of a component.Tensile StrengthOr ultimate strength, is the largest unit stress a material can achieve in a tensile test.Thermal BlockA spacer which has a low thermal conductance.ThrustThe horizontal component of a reaction or an outward horizontal force.TieA rod, plate, or angle welded between a two angle web member or between a top or bottom chord panel to tie them together usually located at the middle of the member. See Filler or Plug.Tie JoistA joist that is bolted at a column.Tilted JoistA joist which is supported in a manner such that the vertical axes of the joist is not perpendicular with respect to the ground.ToeThe outside points of each leg of a structural angle.Toe of Fillet1) The end or termination edge of a fillet weld 2)The end or termination edge of a rolled section fillet.Toe of WeldThe junction between the face of a weld and the base metal.TonA unit of weight equal to 2000 pounds.Top ChordThe top member of a joist or joist girder.Top Chord BearingThe bearing condition of a joist or joist girder that bears on its top chord seat.Top Chord Extension (TCX)The extended part of a joist top chord only. This type has only the two top chord angles extended past the joist seat. See Overhang.

Torque WrenchA wrench containing an adjustable mechanism for measuring and controlling the amount of turning force exerted when used to tighten nuts and bolts.Torsion LoadsA load that causes a member to twist about its longitudinal axis. Simple torsion is produced by a couple or moment in a plane perpendicular to the axis.TOSAbbreviation for 'Top of Steel'.ToughnessThe ability of a steel to absorb large amounts of energy without being readily damaged.TransverseCrossing from side to side or placed crosswise.Tribuitary Width or AreaThe design area which contributes load to a structural member. It is one half the distance between members on either side of the member.Trimmer JoistOne of the joists supporting a header. The header applies a concentrated load at that point on the trimmer joist.TrussIn general, a structural load-carrying member with an open web system designed as a simple span with each member designed to carry a tension or compression force. The entire structure act will act like a beam.TubeA hollow structural steel member shaped like a square or rectangle used as a beam, column, or for bracing. Usually the nominal outside corner radius is equal to two times the wall thickness.TurnbuckleA rotating sleeve or link with internal screw threads at each end and used to tighten or connect the ends of a rod.Turn-of-the-Nut-MethodA method for pre-tensioning high-strength bolts by the rotation of the wrench a predetermined amount after the nut has been tightened to a snug fit.[Return to Glossary][U]

UBC (Uniform Building Code)A minimum model regulatory code for the protection of public health, safety, welfare and property by regulating and controlling the design, construction, quality of materials, use, occupancy, location and maintenance of all buildings and structures within a jurisdiction.UL (Underwriters Laboratories, Inc.)A non-profit product safety testing and certification organization.Ultimate LoadThe force necessary to cause rupture.Ultimate StrengthThe maximum stress attained by a structural member prior to rupture which is the ultimate load divided by the orginial cross-sectional area of the member.Ultimate Strength DesignSee LRFD.Unbraced FrameA frame providing resistance to lateral load by the bending resistance of the frame members and their connections.Unbraced LengthThe distance between points of bracing of a structural member, measured between the centers of gravity of the bracing members.Unbraced Top ChordThe specific length where the top chord of a joist has no lateral bracing by deck, bridging, or any other means.UndercutA notch or groove melted into the base metal next to the toe or root of a weld and left unfilled by weld metal.UnderslungDescription of a joist which is suspended from upper support points where most of the mass of steel is below the actual support points.Uniformly Distributed LoadA load or force, for practical purposes, that may be considered constant over the entire length or partial length of the member.UNO

Abbrevation for 'Unless Noted Otherwise'.UpliftThe wind load on a member which causes a load in the upward direction. The gross uplift is determined from various codes and is generally a horizontal wind pressure multiplied by a factor to establish the uplift pressure. The net uplift is the gross uplift minus the allowable portion of dead load including the weight of the joist and is the load that the specifying professional shall indicate to the joist manufacturer.Uplift BridgingThe bridging required by uplift design. Usually always required at the first bottom chord panel point of a K-Series, LH- or DLH-Series joist and at other locations along the bottom chord as required by design.Upstanding LegThe leg of a structural angle which is projecting up from you when viewing.[Return to Glossary][V]

ValleyThe angle formed by two sloping sides of a roof.Value EngineeringThe application of the Scientific Method to the study of selecting the optimum or best system that meets the need of the customer.Vapor BarrierA physical membrane which prevents moisture or water vapor from penetrating to the other side.Varying Distributed LoadA load or force, for practical purposes, that may be considered varying over the surface of the member, for example a snow drift.VG-Type Joist GirderA type of Joist Girder where joists are located at panel points where vertical webs intersect the top chord only. This type of girder is used for ducts to pass thru since the joists do not interfere with their passage.VibrationThe oscillating, reciprocating, or other periodic motion of a rigid or elastic body or medium such as a floor when its position or state of equilibrium has been changed.[Return to Glossary][W]

W ShapesA hot rolled shape called a Wide Flange Shape with symbol W which has essentially parallel flange surfaces.WallA vertical or near vertical structure which encloses or separates spaces and may be used to resist horizontal or vertical forces or bending forces.Wall AnchorA small piece of angle or other structural material that is usually bolted to a wall to which a starter joist or bridging angle is welded or bolted to.Wall CoveringThe exterior wall skin consisting of sheets or panels.WasherA flat ring of metal with a hole in the middle used to give thickness to a joint or to distribute pressure under the head of a nut or bolt.Weak AxisThe cross section which has the minor principal axis.Weathering SteelA type of high-strength steel which can be used in normal outdoor environments without being painted. Should not be used in corrosive or marine environments.Web1) The vertical or diagonal members joined at the top and bottom chords of a joist or joist girder to form triangular patterns or 2) The portion of a structural member between the flanges.Web BucklingThe buckling of a web plate.Web ConfigurationThe arrangement of the actual web system of a joist or joist girder which can be shown with a profile view of the member.Web CripplingThe local failure of a web plate in the region of a concentrated load or reaction.Welded Splice

A splice between two materials which has the joint made continuous by the process of welding.WeldingThe process of joining materials together, usually by heating the materials to a suitable temperature.WeldabilityIs the ability of a steel to be welded without its basic mechanical properties being changed.Welding WasherA metal device with a hole through it to allow for plug welding of deck to structural steel.Wind ColumnA vertical member supporting a wall system designed to withstand horizontal wind loads. Usually between two main vertial load carrying columns.Wind LoadA force or lateral pressure in pounds per square foot that is applied to a member due to wind blowing in any direction.WindwardThe direction or side toward the wind. Opposite of leeward.Working DrawingsThe complete set of architectural drawings prepared by a registered architect.Working LoadAlso called service load, is the actual load that is acting on the structure.Working PointThe point where two or more centroid lines of structural members intersect.WRC (Welding Research Council)This organization conducts cooperative research in welding with interested scientific societies, government departments, and any company using welded products.WSD (Working Stress Design)A structural design method whereby a structural element is designed so that the unit stresses computed under the action of working or service loads do not exceed the specified allowable values. See Allowable Stress Design and Elastic Design.WTA hot rolled structural tee shape with symbol WT which is cut or split from W Shapes.[Return to Glossary][X]

X-BraceStructural bracing which resembles the letter "X".[Return to Glossary][Y]

Yield Point (Fy)Is that unit stress at which the stress-strain curve exhibits a definite increase in strain without an increase in stress which is less than the maximum attainable stress.Young's ModulusSee Modulus of Elasticity.[Return to Glossary][Z]

Z SectionA structural section in the shape of a "Z" cold formed from a steel sheet.[Return to Glossary]

Are extra items that can be furnished in addition to the base joist or joist girder. They include: headers, top chord extensions, extended ends, ceiling extensions, bottom chord extensions, sloped end bearings, bridging, bridging anchors, joist girder bottom chord bracing, or angle units (joist substitutes).

Is a national trade organization of qualified construction contractors and and industry related companies dedicated to skill, integrity, an responsibility. The AGCA is the voice of the construction industry and is dedicated to improving the quality of construction and protecting the public.

Is a non-profit technical specifying and trade organization for the fabricated structural steel industry in the United States. It was founded in 1921 with headquarters located in Chicago. One of their best known manuals is the Manual of Steel Construction.

A nomograph for estimating the effective length factor, K, of columns in an unbraced frame. Note that the chart is based upon assumptions of idealized conditions which seldom exist in real structures.

A measure of floor vibration. It is the magnitude or total distance traveled by each oscillation of the vibration.

A multiplier of the value of moment or deflection in the unbraced length of an axially loaded member to reflect secondary values generated by the eccentricity of the load.

A long 'L' shaped bolt which is set in concrete and used to anchor columns or other members to a foundation or other support.

The process of fastening a joist or joist girder to a masonry, concrete, or steel support by either bolting or welding.

A member used as a joist substitute which is intended for use at very short spans (10 feet or less) where open web steel joists are impractical. They are usually used for short spans in skewed bays, over corridors, or for outriggers. It can be made up of two or four angles to form channel sections or box sections. Tube and channel sections are also used. See Joist Substitute.

Plans sent by the joist manufacturer to the buyer, engineer, architect, contractor or other person for approval. The plans may include a framing plan, elevations, sections, and a material list.

A non-standard type of joist where both the top chord and bottom chord are curved parallel with each other.

A person who designs buildings or other structures and has completed schooling in building design or similar subjects and is licensed by the state as an architect.

Founded in 1852, is the oldest national professional engineering society in the United States. It is dedicated to the advancement of the individual civil engineer and the civil engineering profession through education.

A structural design method whereby a structural element is designed so that the unit stresses computed under the action of working or service loads do not exceed specified allowable values. See Working Stress Design and Elastic Design.

An organization which has developed over 10,000 technical standards which are used by industries worldwide.

An opening or skylighted lobby through two or more floor levels other than an enclosed stairway, elevator, etc.

The world's most popular computer-aided drafting software product for the personal computer in both DOS and windows by Autodesk, Inc. Anything that can be drawn on a drawing board can be drawn by AutoCAD.

An organization established in 1984 to bridge the gap between the findings of basic welding research and the needs of the industry.

A non-profit organization whose major goal is to advance the science, technology, and application of welding and related joining disciplines.

A load whose line of action passes through the centroid of the member's cross-sectional area and is perpendicular to the plane of the section.

A welding aid used to prevent melting through of a joint when preforming, for example, a complete-joint penetration groove weld.

A roof which has selected material, such as crushed stone, placed on its surface to hold down the roof from wind forces.

A steel plate welded to the base of a column which distributes the column loads over an area of foundation large enough to prevent crushing of the concrete and usually secured by anchor bolts.

A small piece of angle or plate welded to the heels of a two angle web member or any two parallel components to tie them together and usually located at the middle of the member.

A minimum model regulatory code for the protection of public health, safety, welfare and property by regulating and controlling the design, construction, quality of materials, use, occupancy, location and maintenance of all buildings and structures within a jurisdiction.

A structural member, usually horizontal, whose main function is to carry loads transverse to its longitudinal axis. These loads usually cause bending of the beam member. Some types of beams are simple, continuous, and cantilever.

A structural member whose main function is to carry loads both parallel and transverse to its longitudinal axis.

1) The distance that the bearing shoe or seat of a joist or joist girder extends over its masonry, concrete, or steel support 2) A structural support, usually a beam or wall, that is designed by the specifying professional to carry reactions to the foundation

The steel plate used for a joist or joist girder to bear on when they are supported by masonry or concrete supports. This plate transfers the joist reaction to the supporting structure and must be sized accordingly.

The condition in the analysis of the internal stresses across the cross section of a member when it is subjected to forces which cause it to bend.

Is zero at the neutral axis and assumed to increase linearly to a maximum at the outer fibers of the section.Formula in the elastic range: Bending stress (in psi)=(M * c)/I, where 'M' is the bending moment at the section in in-lbs, 'I' is the moment of inertia of the section in inches^4, and 'c' is the distance from the neutral axis to the point at which the stress is desired in inches.

The plane of beam or joist girder members which support loads and the columns which support these members.

A type of Joist Girder where joists are located at all panel points where vertical webs and diagonal webs intersect the top chord.

The phenomenon whereby a perfectly straight member may either assume a deflected position, deflect then twist out of plane, or may remain in an undeflected configuration.

A list that gives each part or mark number, quantity, length of material, total weight, or other description of each piece of material that is shipped to a jobsite. The receiver compares each item on this list to what is on the truck and signs the statement. See also Shipping List.

Also called a blue line. Is a copy of an architectural or other drawing made by a special machine usually on white paper with the lines and text being a blue color.

A minimum model regulatory code for the protection of public health, safety, welfare and property by regulating and controlling the design, construction, quality of materials, use, occupancy, location and maintenance of all buildings and structures within a jurisdiction. Its serves primarily the North Central and Northeast United States.

The connection between two structural members joined at their ends by bolting to form a single, longer member.

The top course of block of a masonry wall filled with concrete and reinforcing steel and used to support roof loads.

A bearing condition where the joist or joist girder bears on its bottom chord and not at an underslung condition.

The two angle extended part of a joist bottom chord from the first bottom chord panel point towards the end of the joist.

An idealization to model how a structure is attached to its "external" points of support, for example, pin, fixed, roller, or shear release.

Used in a graphical analysis of a joist or joist girder. It is a notation for denoting truss joints, members, loads, and forces. Capital letters are placed in the spaces between truss members and between forces. Each member and load is then designated by the letters on opposite sides of it.

A lifting system which has a hoist that moves laterally on a beam or other member which then in turn moves longitudinally on a runway made of beams and rails.

In general, is a member connected to a joist to brace it from lateral movement. See Horizontal Bridging and Diagonal Bridging.

An angle or bent plate attached to a wall where the bridging will be attached or anchored, either by welding or bolting. The ends of all bridging lines terminating at walls or beams shall be anchored thereto.

A small piece of angle or plate with a hole or slot that is welded to the top and bottom chord angles so that bridging may be attached.

Regulations established by a recognized agency describing design loads, procedures, quality of materials, and construction details for buildings for the protection of the public.

A registered architect or registered engineer who is responsible for the design of a structure. See Specifying Professional.

A structural member made up from individual flat plates welded together or any structural metal elements that are welded or bolted together.

The end plate of a structural member usually used to rest or butt against a like plate of another member in forming a connection.

A structural member cold-formed from sheet steel in the shape of a block "C" which can be used by itself or back to back with another C Section.

A mechanical instrument usually having a pair of pivoted legs adjustable to any distance and used to measure thichness, distances between surfaces, and any internal or external diameter which is inaccessible with a scale.

Camber is an upward curvature of the chords of a joist or joist girder induced during shop fabrication to compensate for deflection due to loading conditions. Note, this is in addition to the pitch of the top chord.

A deck accessory which is a short piece of gage steel used at 45 degrees where a wall or parapet meets the end of deck.

A seat which is sloped perpendicular to the member which most joist manufactures do not do. Usually the steel contractor furnishes a bent plate shim to provide level bearing for the seat.

A steel plate welded to the top of a column which a joist, joist girder, or other structural member can bear on.

Suspended structural framing used to provide access to and between areas below a roof and above a floor.

Is similar to a bottom chord extension except that only one angle of the joist bottom chord is extended from the first bottom chord panel point towards the end of the joist.

A theoretical span definition which is the distance between the actual centerlines of a beam, column, joist, or joist girder.

The point in a member at the intersection of two perpendicular axes so located that the moments of the areas on opposite sides of an axis about that axis is zero.

A welder who has been certified by a competent experienced welding inspector or a recognized testing facility in the field of welding. The welder must be certified to make certain welds under qualified procedures. The welder must be qualified for each position, type weld, electrode, and thickness of base metal that is to be welded in the shop or field.

A hot rolled structural shape the looks like "[". There are American Standard Channels designated by (C) and Miscellaneous Channels designated by (MC).

The actual clear distance or opening between supports for a structural member, i.e., the distance between walls or the distance between the edges of flanges of beams.

A U-shaped yoke with internal threads in one end which can be attached to a threaded rod and the other end a connection with a hole used for a pin or bolt attchment.

A structural angle which attaches to the side of a wall, column, beam, etc. where a joist, joist girder, or other structural member bears.

A floor deck accessory made of gage metal which is placed over the ends of deck so that concrete cannot run out of the flutes of the deck.

The process of forming a structural section by bending sheet or strip steel in roll-forming machines without the use of heat.

All additional dead loads other than the weight of the building, such as sprinklers, pipes, ceilings, and mechanical or electrical components.

Is a main vertical member carrying axial loads, which can be combined with bending and shear, from the main roof beams or girders to the foundation. These structural members carry loads parallel to its longitudinal axis.

A steel section whose flanges must be continuously connected to the webs and the width-thickness ratios of its compression element can not exceed the limiting width-thichness ratios designated in the AISC Manual.

A steel beam and a concrete slab connected, usually by shear stud connectors, so that they act together to resist the load on the beam.

A single load or force that has such a small contact area as to be negligible compared with the entire surface area of the supporting member and applied at a certain point on the structure.

A joint connected by welds or bolts used to transmit forces between two or more members. See also Splice.

The term given to a structural system denoting the transfer of loads and stresses from member to member as if there were no connections.

A legal document or agreement, enforceable by law, between two or more parties for the doing of something specified, such as the building of a building or furnishing materials.

Contract drawings, specifications, etc., used to build a structure which define the responsibilities of the parties involved.

All the architectural, structural, mechanical, electrical, etc. plans that make up a legal set of contract documents to build a building by.

Framing using conventional joist, beams, columns, masonry walls, etc. instead of framing used in Metal Building construction.

The process of removing certain sections of a structural steel member to allow easier fitup to the supporting structural member.

Successive courses of masonry projecting from the face of a wall to increase its thickness or to form a shelf or ledge for a structural member to bear on.

A long plate usually welded to the top or bottom flange of a rolled steel beam or to the bottom chord of a joist or joist girder to increase the load carrying capacity of that member.

1) A machine used to move material by means of a hoist. 2) A machine that can usually move and is used to lift heavy materials or to lift members that are to be erected in a structure.

A regular angel whose ends have been 'crimped' in the shape of a 'U' whose out-to-out distance is usually one inch. The actual crimped portion of the angle is only a few inches on each end and the end is inserted between top or bottom chord members to be welded.

Loads due to the weight of the components making up the structure and that are intended to remain permanently in place.

A floor or roof covering made out of gage metal attached by welding or mechanical means to joists, beams, purlins, or other structural members and can be galvanized, painted, or unpainted.

The specific type of deck to be specified, such as Type "B" Wide Rib, Type "F" Intermediate, Type "N" Deep Rib, Type "A" Narrow Rib, Composite, Cellular, etc.

The act of distorting or changing the shape or dimensions of a structural element or body resulting from forces or stresses.

The out-to-out distance from the top of the top chord to the bottom of the bottom chord taken a some reference location, usually at the midspan of the joist or joist girder.

Structural members which are inclined and are usually carrying axial load which enable a structural frame to behave as a truss to resist horizontal loads.

Two angles or other structural shapes connected from the top chord of one joist to the bottom chord of the next joist to form an 'X' shape whose l/r ratio cannot exceed 200. The bridging members are almost always connected at their point of intersection.

Roof panel or decking, metal wall, or floor slab which provides a larger in-plane shear stiffness and strength adequate to transmit horizontal forces to the resisting structural system.

The resistance to a racking affect or in-plane shear forces offered by roof deck, panels, or other structural members when properly attached to a structural frame.

When end moments on a structural member produce a bending effect which cause the member to form an S shape or has a reversal in curvature.

A tapered pin used during the erection process to align holes in steel members which are to be connected by bolting.

The round or square opening required through the web system of a joist or joist girder to allow passage of a duct.

Is the ability of a material to withstand large inelastic deformations without fracture. Structural steel has considerable ductility.

A load that varies with time which includes repeative loads, seismic loads, and other loads created by rapid movement.

The line along the sidewall of a building formed by the intersection of the plane of the roof and the plane of the wall.

The condition that exists when a load is applied on a line of action that does not pass through the centroid of the body it is applied to.

1) A structural angle that is connected around the edge of a joist extension or other member 2) An angle used around the sides of a floor to contain the concrete when it is being poured which is also called a Pour Stop.

The width or region around the edges of a building where uplift values are higher than in the interior of the roof.

The equivalent length, KL, used in compression formulas. This method estimates the interaction effects of the total frame on a compression member by using K factors to equate the strength of a framed compression member of length L to an equivalent pin-ended member of length KL subject to axial load only.

The ratio between the effective length and the unbraced length of a member measured between center of gravities of the bracing members. K values are given for several idealized conditions in which joint rotation and translation are realized.

The moment of inertia of the cross section of a member that remains elastic when partial plastification takes place. See Moment of Inertia.

The transverse distance indicating the amount of slab that acts in conjuction with the supporting member.

The analysis of a member which assumes that material deformation disappears on removal of the force that produced it and the material returns to its original state.

The device through which current is conducted thru to the arc or base metal during the process of welding.

A steel member such as a plate, bolt, stud, or bar cast into a concrete structure which is used to transmit applied loads to the concrete.

The first web member on either end of a joist or joist girder which begins at the top chord at the seat and ends at the first bottom chord panel point.

The horizontal distance from the first top chord panel point at the end of a joist to the first bottom chord panel point.

A moment which is generated at one end or both ends of a joist, joist girder, or beam due to continuous frame action which can be caused by wind, live load, or dead load moment.

A graphical plot indicating the maximum magnitude of an internal force effect such as flexual stess, shear stress, axial stress, torsional stress, etc. due to a series of load combinations.

The equations relating a state of static equilibrium of a member or structure when the resultant of all forces and moments are equal to zero. Three equations must be fulfilled simultaneously: Sum of the forces in the X-direction must equal zero, sum of the forces in the Y-direction must equal zero, and the sum of the moments about any point must equal zero for a two dimensional structure.

A uniform load (in plf) derived from the maximum reaction (in lbs) or the maximum moment (in inch-lbs) of a member carrying various loads.

The process of installing joists, joist girders, beams, bridging, deck, or other structural members in order to construct a structure.

Floor or roof plans that identify individual marks, components, and accessories furnished by the joist manufactures in a detailed mannner to permit proper erection of the joist and joist girders. See Framing Plan and Placing Plan.

A break in construction or a special design detail to allow for thermal expansion and contraction of the materials of a structure.

The extended part of a joist top chord with also the seat angles extended from the end of the jost extension back into the joist maintaining the standard 2 1/2 inch end bearing depth over the entire length of the extension.

The manufacturing process to convert raw materials into a finished product by cutting, punching, welding, cleaning, and painting.

Is the ratio of the ultimate load for a member divided by the allowable load for a member and must always be greater than unity.

For joists and joist girders, when looking at the member with the tagged end to the right, it is the side that is opposite the side you see first.

The flat surface located at the outer end of a roof overhang or cantilever end or also a decorative trim or panel which projects from the face of a wall.

The specific term used for the welding of structural members out at the actual jobsite and not in a fabricators shop.

A rod, plate, or angle welded between a two angle web member or between a top or bottom chord panel to tie them together usually located at the middle of the member. See Tie or Plug.

A roof deck accessory made out of gage metal for finishing out runs of deck for small areas of coverage where full sheet coverage is impractical.

The process of coating a structural steel member with a fire retardant material to make the member resistant to fire.

The ability of a joist or other structural member to resist a fire due to the type of protection it has, such as membrane protection or spray on protection. There are hundreds of floor-ceiling or roof-ceiling assemblies with their fire-resistance rating given in the Underwriters Laboratory Fire Directory.

A condition where no rotation or horizontal or vertical movement can occur at that end. This type of support has no degrees of freedom. Three reactive forces exist at the rigidly fixed end. See also Rigid Connection.

A structural bracing member used to provide lateral support to the flange of a beam, the bottom chord or a joist girder, or a column.

Pieces of sheet metal or the like used to cover and protect joints, etc. where a roof comes in contact with a wall or chimney.

A leader in property loss prevention engineering and adjustment. It helps companies prevent and control property loss through research, engineering, and education.

A moveable wall on a track suspended from a joist or beam which usually folds like an accordion and can be stored in a closet or pocket in a wall.

A concrete pad or mat located under a column, wall, or other structural member that distributes loads from that member into the supporting soil.

A structural framing system consisting of members joined together with moment or rigid connections which maintain their original angular relationship under load without the need for bracing in its plane. See Rigid Frame.

Headers or other structural members which surround an opening in a roof which can be for mechanical units, straiwells, etc.

Floor or roof plans that identify individual marks, components, and accessories furnished by the joist manufactures in a detailed mannner to permit proper erection of the joist and joist girders. See Erection Plan and Placing Plan.

A diagram on which all of the external forces acting on a body are shown at their respective points of application.

A measure of floor vibration. It is the speed of the oscillations of vibration and is expressed in cycles per secong or Hz (Hertz).

A type of Joist Girder where joists are located at panel points where diagonal webs intersect the top chord only.

A non-standard type of joist where the top chord is double pitched at an extreme pitch (say 3/12) and the bottom chord is straight or level.

1) The thickness of a sheet of deck or 2) The distance from centerline hole to centerline hole across a set of holes, usually perpendicular to the joist or joist girder.

A main horizontal, primary structural member spanning between two main supports which carries other members or vertical loads.

A horizontal structural member that is attached to the sidewall or endwall columns supporting sheeting or paneling.

A short beam used like a bearing plate to distribute large reactive loads to a wall such as the load from a joist girder.

A steel plate used to connect structural steel members or to reinforce members. It is usually inserted between the top or bottom chord of a joist or joist girder.

A series of joist adopted in 1961 so proportioned that the allowable tension or bending stress does not exceed 22,000 psi or 30,000 psi depending on whether 36 ksi or 50 ksi yield steel was used.

A structural member located between two joists or between a joist and a wall which carries another joist or joists. Usually made up of an angle, channel, or beam with saddle angle connections on each end for bearing.

A structural steel bolt having a tensile strength greater than 100,000 pounds per square inch, usually A325 or A490.

This type of support has one degree of freedom, it can freely rotate about its axis but it cannot displace in any direction. Two mutually perpendicular reactive forces exist at the hinge and their lines of action pass through the center of the hinge. See Pin Connection or Support.

A roof which slopes from all four sides of a building. The line where two adjacent sloping sides intersect is called the 'hip'.

A chain or electric lifting device usually attached to a trolly which travels along a monorail or bridge crane.

A continuous angle or other structural shape connected to the top and bottom chord of a joist horizontally whose l/r ratio cannot exceed 300.

Is zero at the outer fibers of a section and is maximum at the neutral axis. It tends to cause one part of the section to slide past the other.Formula: Horizontal Shear stress (in psi)=(V * Q)/I*t, where 'V' is the external vertical shear on the section in lbs, 'I' is the moment of inertia of the section in inches^4, 'Q' is the statical moment about the neutral axis of the entire section of that portion of the cross-section lying outside of the cutting plane and 't' is the width at the cutting plane.

Structural steel sections which are formed by rolling mills from molten steel which can be angles, channels, W Shapes, S Shapes, etc.

A hot rolled shape with symbol HP used for bearing piles which have essentially parallel flanges and equal web and flange thickness.

A term that describes the behavior of a structural member subjected to reversed, repeated load into the inelastic range whose plot of load verses displacement is characterized by loops. The amount of energy dissipated during inelastic loading is indicated by the enclosed area within these loops.

A minimum model regulatory code dedicated to public safety through development and promotion of uniform codes and standards.

A weight that is dropped or a dynamic load generated by movement of a live load such as vehicles, craneways, etc.

An influence line is a curve whose ordinates give the values of some particular function (shear, moment, reaction, etc.) in an element due to a unit load acting at the point corresponding to the particular ordinate being considered. Influence lines for statically determinate structures are straight lines and for statically indeterminate structures the lines are curved and their construction involves considerable analysis.

A condition reached when a structure or structural member is loaded in which continued deformation results in a decrease in its load-resisting capacity.

The pressure inside a building which is a function of the wind velocity and the number and locations of openings.

A series of joist adopted in 1961 so proportioned that the allowable tension or bending stress does not exceed 22,000 psi and was made from A36 steel.

A cantilevered boom or beam with a hoist and trolly used to pick up loads in all or part of a circle around which it is attached

A device which holds work or pieces of materal in a certain position until rigidly fastened or welded during the fabrication process.

A structural load-carrying member with an open web system which supports floors and roofs utilizing hot-rolled or cold-formed steel and is designed as a simple span member.

A standard way of communicating the joist safe uniformly distributed load-carrying capacities for a given span such as 16K5 or 24K10 where the first number is the nominal joist depth at midspan and the last number is the chord size. See Longspan Designation and Joist Girder Designation.

A primary structural load-carrying member with an open web system designed as a simple span supporting equally spaced concentrated loads of a floor or roof system acting at the panel points of the joist girder and utilizing hot-rolled or cold-formed steel.

A standard way of communicating the girder design loads such as 48G6N10.5K where the first number is the nominal girder depth at midspan, 6N is the number of joist spaces on the span of girder, and 10.5K is the kip load on each panel point of the girder. The approximate dead load weight of the member is included in the kip load. See Joist Designation and Longspan Designation.

A structural member which is intended for use at very short spans (10 feet or less) where open web steel joists are impractical. They are usually used for short spans in skewed bays, over corridors, or for outriggers. It can be made up of two or four angles to form channel sections or box sections. See Angle Unit.

Is a K-Series joist that is designed to support uniform load plus concentrated loads or other non-uniform loads.

A small reference plan or outline of the whole building on each plan sheet divided into smaller areas for which each sheet is drawn. It can also show different sequences, phases, sheet number that area is drawn on, etc.

A vertical plate used as a joist seat whose width is small for bearing purposes. It is used for hip and valley bearing conditions, canted seat conditions, and extreme skewed conditions.

Is a separation or crack in the base metal caused by through-thickness weld shrinkage strains of adjacent weld metal.

The direction toward which the wind is blowing, which is opposite the side from which the wind blows. Opposite of windward.

A horizontal structural member spanning a door, window, or other wall opening which supports a wall or any construction immediately above.

Loads on a member that are not permanent and are likely to be moved at some point in the life of the structure. They can be loads produced by the use and occupancy of the building. These loads do not include dead load, wind load, snow load, or seismic load.

An external force or other action acting on a member or structure. It can be from permanent construction, environmental effects, differential settlement, occupants, and material objects.

A table of standard joist designations which give the total safe uniformly distributed load-carrying capacities and live load-carring capacities of the joists for different span lengths. The table also gives the approximate weight per foot of each joist designation.

A diagram which shows all design loads and design criteria that a member is to be designed for. The loads include: dead load, live load, snow drift, concentrated loads, moments, etc. The design criteria include: deflection requirements, load combinations, net uplift, one-third increase in allowable stress allowed or not, etc.

A standard way of communicating the longspan joist safe uniformly distributed load-carrying capacities for a given clear span such as 18LH06 or 36LH10 where the first number is the nominal joist depth at midspan and the last number is the section number. See Joist Designation and Joist Girder Designation.

A structural load-carrying member with an open web system which supports floors and roofs utilizing hot-rolled or cold-formed steel and is designed as a simple span member. These carry higher loads than a regular joist.

A single or double angle either welded or bolted at the first bottom chord panel point and extended to brace another member such as a beam, joist girder, frame, or wall.

A method of proportioning structural members such that no limit state is exceeded when all appropriate load combinations have been applied.

A hot rolled shape called a Miscellaneous Shape with symbol M that cannot be identified as W, HP, or S Shapes.

The axis of a structural member possessing the largest section modulus and radius of gyration, thus having the greatest flexural and axial compressive strength.

An identification number or method of relating to the erector which joist, joist girder or other separate part of the building goes at what location when being erected, i.e., J1, K25, L7, G12, or JG9. See Piece Mark and Part Number.

A type of construction from materials such as concrete blocks, bricks, concrete, stone, or ceramic blocks which is laid unit by unit and set in mortar.

A graphical method of determining stresses in a truss by combining force polygons of all the joints into one stress diagram.

An association of manufacturers of metal building systems whose objectives are to compile and publish recommended design standards which will insure high quality metal buildings.

An air conditioner or other unit either placed on top of a roof system or hung below which applies loads to joist or joist girders.

An idealization to model how members are attached to "each other". It designates whether forces and moments at the ends of a member are considered fixed to or released from the member's point of attachment.

A building system consisting of a group of coordinated components which have been designed for a certain loading. These components are mass produced and assembled in various combinations with other structural materials to produce a building.

Is a not-for-profit organization which was formed to advance the interests of the material handling industry which includes the movement, storage, control, and protection of material and products throughout the process of their manufacture, distribution, consumption, and disposal.

A report of a heat of steel that indicates the customer's order number, grade of steel, number and dimensions of pieces shipped, and the chemical compositional makeup of hot rolled structural steel members. It also indicates physical properties, such as, yield strength, tensile strength, elongation, impact, and ultimate strength.

The axis of a structural member possessing the smallest section modulus and radius of gyration, thus having the least flexural and axial compressive strength.

Is the slope of the straight-line portion of the stress-strain curve in the elastic range found by dividing the unit stress in ksi by the unit strain in in/in. For all structural steels, the value is usually taken as 29,000 ksi. This is also called Young's Modulus.

The tendency of a force to cause a rotation about a point or axis which in turn produces bending stresses.

A connection designed to transfer moment as well as axial and shear forces between connecting members.

A physical property of a member which helps define rigidity or stiffness and is expressed in inches raised to the fourth power. It is a measure of the resistance to rotation offered by a section's geometry and size.

A welded steel plate used to develop a rigid connection to the supporting member so that moment transfer can occur.

Strips of lumber attached to the top chord of a joist so plywood or other flooring can be nailed at 36 inches maximum on center.

A minimum model regulatory code for the protection of public health, safety, welfare and property by regulating and controlling the design, construction, quality of materials, use, occupancy, location and maintenance of all buildings and structures within a jurisdiction.

For joists and joist girders, when looking at the member with the tagged end to the right, it is the side you see first and is closest to you.

The surface in a member where the stresses change from compression to tension, i.e., represents zero strain and therefore zero stress. The neutral axis is perpendicular to the line of applied force.

An international nonprofit organization to reduce the burden of fire on the quality of life by proposing codes and standards, research, and education on fire related issues.

An organization that works with industry and government to advance measurement science and develop standards.

A steel section which does not qualify as a compact section and the width-thickness ratios of its compression elements do not exceed the values designated in the AISC Manual.

A structure which cannot maintain its shape and may undergo large displacements and would collapse under its own weight when not supported externally.

When the ridge of a joist that has the top chord pitched two ways is not in the center of the member or bay.

When designing steel members for forces produced by wind or seismic conditions, the allowable stresses in the design formulas may be increased 1/3 above the values otherwise provided.

A federal organization whose purpose is to save lives, prevent injuries, and protect the health of the workers of America.

A structural member which is usually perpendicular to a joist and attaches under the outstanding leg of one of the joist top chord angles. It then bears on a beam or wall and cantilevers across, similar to a top chord extension.

The extension of the top chord of a joist beyond the outside of the bearing support. See Top Chord Extension.

When joists are erected in multiple bays, they begin to hit each other end to end (or pack out) because the center to center of beam is not true or the joists are to long.

1) The distance between two adjacent panel points of a joist or joist girder 2) A sheet of deck for a roof or floor.

The point where one or more web members intersect the top or bottom chords of a joist or joist girder. See Joint.

Type of joist or joist girder which has its top and bottom chords parallel to each other. The member can be sloped and still have parallel chords.

The portion of a vertical wall of a building which extends above the roof line at the intersection of the wall and roof.

A type of connection that displays a moment rotation behavior that can neither be described as pinned nor fixed.

A wall that is one story or less in height used to subdivide the interior space in a building and can be a bearing wall or a non-bearing wall.

The highest point of a gable or also the highest point on a joist or joist girder where the sloped chords meet. See also Apex.

An official document or certificate by a governmental agency or building official authorizing performance of a building process or other specified activity.

A reinforced or enlarged portion of a masonry wall to provide support for vertical roof loads or lateral loads on the wall.

A connection where no moment is transfered from one member to another, only axial and shear forces. This type of support has one degree of freedom, it can freely rotate about its axis but it cannot displace in any direction. Two mutually perpendicular reactive forces exist at the pin and their lines of action pass through the center of the pin. See Hinge Support.

A hollow cylinder of metal used for the conveyance of water or gas or used as a structural column which comes in sizes of standard, extra strong and double-extra strong.

A structural system where two joists are used to carry loads such as piping or ducts. The two joists have to have diagonal bridging and their top and bottom chords have to be laced together with structural members to provide stability for the whole structure,

Is the slope or inclination of a member. It is defined as the ratio of the total rise to the total width. It also is defined as the angle that the top chord makes with the lower chord. There can be single or double pitched members.

The North arrow symbol on a contract drawing usually 90 degrees to the longitudinal axis of the plan so that communication will be easier for the elevations of the building, sections, etc.

A design concept based on multiplying the actual design loads by a suitable load factor and then using the yield stress as the maximum stress in any member.

A rod, plate, or angle welded between a two angle web member or between a top or bottom chord panel to tie them together usually located at the middle of the member. See Tie or Filler.

A weld in a slot in a piece of steel which overlaps another piece. A principle use for a plug weld is to transmit shear in a lap joint. See Slot Weld and Puddle Weld.

Defined as the ratio of the unit lateral strain to the unit longitudinal strain. It is constant for a material within the elastic range. For structural steel, the value is usually taken as 0.3. It gradually increases beyond the proportional limit, approaching 0.5.

Is the sum of any two moments of inertia about axes at right angles to each other. It is taken about an axis which is perpendicular to the plane of the other two axes.

A rigid frame structure which is designed to resist longitudial loads where diagonal bracing is not permitted. It has rigidity and stability in its plane.

To manufacture or construct parts or sections of structural assemblies beforehand that are ready for quick assembly and erection at a jobsite.

The initial coating of a member applied in the shop which is not a finish coat and only protects from rust for a limited time.

A drawing or diagram which shows the outline of a joist with dimensions and also maybe the web system configuration and bridging rows. See Side-View Diagram

The point on a stress-strain curve where the linear relationship between stress and strain ends and usually coincides with the material yield point.

Usually a cold-formed horizontal structural member attached perpendicular to the joist top chord or main frames of a building for support of the roof deck.

Is the distance from the neutral axis of a section to an imaginary point at which the whole area of the section could be concentrated and still have the same moment of inertia.Formula: The square root of (the moment of inertia in inches^4 divided by the area of the section in inches^2) expressed in inches.

The reconstruction or renewal of any part of an existing structure or building for the purpose of its maintenance.

The highest point on the roof of a building formed by two intersecting slopes or the horizontal line made by the top surfaces of the two intersecting sloping roof surfaces.

A structural framing system consisting of members joined together with moment or rigid connections which maintain their original angular relationship under load without the need for bracing in its plane. See Frame and Stability.

An institute organized in 1958 by industry leaders as a not-for-profit trade association. Its mission is to advance standards, quality, safety, and general fitness for intended use of industrial steel storage rack systems.

This type of support has two degrees of freedom, it can freely rotate about its axis or displace in one direction in the plane. Only one reactive force exists at a roller which acts perpendicular to the path of the displacement and its line of action passes through the center of the roller.

The angle connection or seat on the end of a header or frame which bears from the side on the top chord of a joist. This angle should be designed to carry the reaction of the header or frame to the center of the joist and must rest on and weld to both top chord angles.

A minimum model regulatory code for the protection of public health, safety, welfare and property by regulating and controlling the design, construction, quality of materials, use, occupancy, location and maintenance of all buildings and structures within a jurisdiction.

A non-standard type of joist where both the top chord and bottom chord are double pitched and parallel with each other.

An institute which brings uniformity to the design, manufacture, quality control, and construction practices applicable to cold-formed steel deck.

An organization that sets uniform standards among the many steel erectors and helps promote safety in the erection industry.

The out-to-out depth of the end bearing shoe or seat of a joist or joist girder which is the distance from the top of the top chord to the bottom of the bearing seat angle or plate.

A physical property of strength of a structural member. It relates bending moment and maximum bending stress within the elastic range. Formula: S=I/c where 'I' is the moment of inertia of the cross-section about the neutral axis in inches^4 and 'c' is the distance from the neutal axis to the outermost fibers.

Are assumed lateral forces acting in any horizontal direction that produce stresses or deformations in a structural member due to the dynamic action of an earthquake.

A mechanical fastener for attaching deck, panels, or other materials to a structure which taps its own threads in a predrilled hole.

A breakdown of when materials are to be made or delivered for a project with one following after the other.

The distance from the outside edge of an angle or other member to the edge of a gusset plate or angle welded near the end.

An interior space, enclosed by walls, which extends through one or more stories or basement which connects successive floors and/or roof for elevators, dumbwaiters, mechanical equipment, etc.

The ratio of the plastic section modulus Z to the elastic section modulus S or the ratio of the plastic moment Mp to the yield moment My.

A condition or force causing two contacting parts of a material to slide past each other in opposite directions parallel to their plane of contact.

The point in a cross section of a structural member to which a load may be applied and not induce any torsional stress in the cross section.

A boundary condition which constrains a member end from axial displacement and rotation but allows movement in a direction perpendicular to the members longitudinal axis.

A steel device used in composite design which is welded to the top flange of a beam or top chord of a joist which transfers shear from a concrete slab to the supporting member.

A list that gives each part or mark number, quantity, length of material, total weight, or other description of each piece of material to be shipped to a jobsite. See also Bill of Ladding.

1) Can also be called the erection plans or framing plans 2) The actual drawings used by a shop to fabricate a product which includes all dimensions, materials, tolerances, etc.

A drawing or diagram which shows the outline of a joist with dimensions and also maybe the web system configuration and bridging rows. See Profile Drawing.

A span with supports at each end, no intermediate support, that restrain only against vertical displacement with the ends of the member being free to rotate.

When moments produce a deformed or bent shape of a structural member having a smooth continuous curve or arc.

A type of roofing system using thermoplastic membranes which are seamed by either hot air or solvent welding of one sheet to the next or using thermoset membranes which are seamed with an adhesive.

The institute is a non-profit organization of active joist manufacturers that maintains sound engineering practice throughout the joist industry. The institute coopera Wtes with business and government agencies to establish steel joist standards and does continuing research of their products to maintain the integrity of their products.

The condition when two entities come together at an angle which is not 90 degrees or perpendicular to each other.

An opening or roof accessory in a roof or ceiling for admitting light. If it bears across a joist, the top chord angles may be unbraced for design considerations.

A non-metallic byproduct of the welding process forming a hard crust over the molten steel which should be chipped away for inspection of a weld.

A steel section whose width-thickness ratios of any compression element exceeds the values of a noncompact section.

The ratio of the effective length of a column to the radius of gyration of the column about the same axis of bending.

The angle or inclination a structural member makes with reference to a horizontal position expressed in inches of vertical rise per 12 inches of horizontal run, i.e. 3/12.

The distance between supports which is the centerline of a beam, column, or joist girder or 4 inches onto a wall.

A structural member at the outside wall of a building, supporting part of the floor or roof and possibly the wall above.

A design required by a loading diagram or other special notes because a standard joist or joist girder cannot be specified from a load table.

An architect or engineer, registered or licensed to practice professional architecture or engineering, as defined by the statutory requirements of the professional registration laws. See Building Designer.

The connection between two chord members or other structural members joined at their ends by welding or bolting to form a single, longer member.

A system for fire protection usually consisting of overhead piping connected to a water supply to which automatic sprinklers are attached that discharges water in a specific pattern for extinguishment or control of a fire.

Formula: number of squares = sum of(length of deck sheet in feet * width of deck sheet in feet * number of pieces)divided by 100.

A professional technical society whose primary objective is to improve the technology and practice of prolonging the life of steel and concrete structures through the use of protective coatings.

A type of roof system where the deck is attached to clips which are then attached to the beam or joist. Usually this type of roof system cannot be counted on to provide lateral stability or support to the joist top chord.

The property of a body to maintain its shape and remain rigid when detached from its support. Also see Rigid Frame or Structure.

A steel plate at a column or wall inserted between the end of a bottom chord of a joist or joist girder to weld the bottom chord to or to restrain the bottom chord from lateral movement.

A member or structure that can be analyzed and the reactions and forces determined from the equations of equilibrium.

A member or structure that cannot be analyzed soley by the equations of statics. It contains unknowns in excess of the number of equilibrium equations available. Additional equations must be written based on a knowledge of elastic deformations.

A member used to strengthen another member against buckling or to distribute load or to transfer shear. Usually a flat bar, plate, or angle welded perpendicular to the longitudinal axis of the member.

The resistance to deformation of a structural member which can be measured by the ratio of the applied force to the corresponding displacement.

That portion of a building which is between the upper surface of any floor and the upper surface of the floor next above.

The condition when ductile steel exhibits the capacity to resist additional load than that which caused initial yielding after undergoing deformation at or just above the yield point.

An internal force that resists a load. It is the intensity of force per unit of area, i.e., psi (pounds per square inch).

A localized stress which is considerably higher than average due to sudden changes in loading or sudden changes in geometry.

A mechanism designed and built or constructed of various parts jointed together in some definite manner to carry loads and resist forces.

A large number of steels that are suitable for load-carrying members in a variety of structures because of strength, economy, ductility, and other properties. Strength levels are obtained by varying the chemical composition and by heat treatment.

A wood or metal vertical wall member to which exterior or interior covering material may be attached. It can be either load bearing or non-load bearing.

A metal deck accessory used at drain locations to close the opening where holes are cut in the metal deck.

This is the end of a joist or joist girder where an identification or piece mark is shown by a metal tag. The member must be erected with this tagged end in the same position as the tagged end noted on the erection plan.

Anything which is built which will not become part of the permanent structural system and will eventually be removed before or after the completion of the structure.

The longitudinal pulling stress a material can withstand without tearing apart or the maximum tensile stress the material can sustain.

A rod, plate, or angle welded between a two angle web member or between a top or bottom chord panel to tie them together usually located at the middle of the member. See Filler or Plug.

A joist which is supported in a manner such that the vertical axes of the joist is not perpendicular with respect to the ground.

The extended part of a joist top chord only. This type has only the two top chord angles extended past the joist seat. See Overhang.

A wrench containing an adjustable mechanism for measuring and controlling the amount of turning force exerted when used to tighten nuts and bolts.

A load that causes a member to twist about its longitudinal axis. Simple torsion is produced by a couple or moment in a plane perpendicular to the axis.

The design area which contributes load to a structural member. It is one half the distance between members on either side of the member.

One of the joists supporting a header. The header applies a concentrated load at that point on the trimmer joist.

In general, a structural load-carrying member with an open web system designed as a simple span with each member designed to carry a tension or compression force. The entire structure act will act like a beam.

A hollow structural steel member shaped like a square or rectangle used as a beam, column, or for bracing. Usually the nominal outside corner radius is equal to two times the wall thickness.

A rotating sleeve or link with internal screw threads at each end and used to tighten or connect the ends of a rod.

A method for pre-tensioning high-strength bolts by the rotation of the wrench a predetermined amount after the nut has been tightened to a snug fit.

A minimum model regulatory code for the protection of public health, safety, welfare and property by regulating and controlling the design, construction, quality of materials, use, occupancy, location and maintenance of all buildings and structures within a jurisdiction.

The maximum stress attained by a structural member prior to rupture which is the ultimate load divided by the orginial cross-sectional area of the member.

A frame providing resistance to lateral load by the bending resistance of the frame members and their connections.

The distance between points of bracing of a structural member, measured between the centers of gravity of the bracing members.

The specific length where the top chord of a joist has no lateral bracing by deck, bridging, or any other means.

A notch or groove melted into the base metal next to the toe or root of a weld and left unfilled by weld metal.

Description of a joist which is suspended from upper support points where most of the mass of steel is below the actual support points.

A load or force, for practical purposes, that may be considered constant over the entire length or partial length of the member.

The wind load on a member which causes a load in the upward direction. The gross uplift is determined from various codes and is generally a horizontal wind pressure multiplied by a factor to establish the uplift pressure. The net uplift is the gross uplift minus the allowable portion of dead load including the weight of the joist and is the load that the specifying professional shall indicate to the joist manufacturer.

The bridging required by uplift design. Usually always required at the first bottom chord panel point of a K-Series, LH- or DLH-Series joist and at other locations along the bottom chord as required by design.

The application of the Scientific Method to the study of selecting the optimum or best system that meets the need of the customer.

A load or force, for practical purposes, that may be considered varying over the surface of the member, for example a snow drift.

A type of Joist Girder where joists are located at panel points where vertical webs intersect the top chord only. This type of girder is used for ducts to pass thru since the joists do not interfere with their passage.

The oscillating, reciprocating, or other periodic motion of a rigid or elastic body or medium such as a floor when its position or state of equilibrium has been changed.

A hot rolled shape called a Wide Flange Shape with symbol W which has essentially parallel flange surfaces.

A vertical or near vertical structure which encloses or separates spaces and may be used to resist horizontal or vertical forces or bending forces.

A small piece of angle or other structural material that is usually bolted to a wall to which a starter joist or bridging angle is welded or bolted to.

A flat ring of metal with a hole in the middle used to give thickness to a joint or to distribute pressure under the head of a nut or bolt.

A type of high-strength steel which can be used in normal outdoor environments without being painted. Should not be used in corrosive or marine environments.

1) The vertical or diagonal members joined at the top and bottom chords of a joist or joist girder to form triangular patterns or 2) The portion of a structural member between the flanges.

The arrangement of the actual web system of a joist or joist girder which can be shown with a profile view of the member.

A vertical member supporting a wall system designed to withstand horizontal wind loads. Usually between two main vertial load carrying columns.

A force or lateral pressure in pounds per square foot that is applied to a member due to wind blowing in any direction.

This organization conducts cooperative research in welding with interested scientific societies, government departments, and any company using welded products.

A structural design method whereby a structural element is designed so that the unit stresses computed under the action of working or service loads do not exceed the specified allowable values. See Allowable Stress Design and Elastic Design.

Is that unit stress at which the stress-strain curve exhibits a definite increase in strain without an increase in stress which is less than the maximum attainable stress.

Are extra items that can be furnished in addition to the base joist or joist girder. They include: headers, top chord extensions, extended ends, ceiling extensions, bottom chord extensions, sloped end bearings, bridging, bridging anchors, joist girder bottom chord bracing, or angle units (joist substitutes).

Is a national trade organization of qualified construction contractors and and industry related companies dedicated to skill, integrity, an responsibility. The AGCA is the voice of the construction industry and is dedicated to improving the quality of construction and protecting the public.

Is a non-profit technical specifying and trade organization for the fabricated structural steel industry in the United States. It was founded in 1921 with headquarters located in Chicago. One of their best known manuals is the Manual of Steel Construction.

A member used as a joist substitute which is intended for use at very short spans (10 feet or less) where open web steel joists are impractical. They are usually used for short spans in skewed bays, over corridors, or for outriggers. It can be made up of two or four angles to form channel sections or box sections. Tube and channel sections are also used. See Joist Substitute.

Founded in 1852, is the oldest national professional engineering society in the United States. It is dedicated to the advancement of the individual civil engineer and the civil engineering profession through education.

A structural design method whereby a structural element is designed so that the unit stresses computed under the action of working or service loads do not exceed specified allowable values. See Working Stress Design and Elastic Design.

The world's most popular computer-aided drafting software product for the personal computer in both DOS and windows by Autodesk, Inc. Anything that can be drawn on a drawing board can be drawn by AutoCAD.

A minimum model regulatory code for the protection of public health, safety, welfare and property by regulating and controlling the design, construction, quality of materials, use, occupancy, location and maintenance of all buildings and structures within a jurisdiction.

A structural member, usually horizontal, whose main function is to carry loads transverse to its longitudinal axis. These loads usually cause bending of the beam member. Some types of beams are simple, continuous, and cantilever.

1) The distance that the bearing shoe or seat of a joist or joist girder extends over its masonry, concrete, or steel support 2) A structural support, usually a beam or wall, that is designed by the specifying professional to carry reactions to the foundation

Formula in the elastic range: Bending stress (in psi)=(M * c)/I, where 'M' is the bending moment at the section in in-lbs, 'I' is the moment of inertia of the section in inches^4, and 'c' is the distance from the neutral axis to the point at which the stress is desired in inches.

A list that gives each part or mark number, quantity, length of material, total weight, or other description of each piece of material that is shipped to a jobsite. The receiver compares each item on this list to what is on the truck and signs the statement. See also Shipping List.

A minimum model regulatory code for the protection of public health, safety, welfare and property by regulating and controlling the design, construction, quality of materials, use, occupancy, location and maintenance of all buildings and structures within a jurisdiction. Its serves primarily the North Central and Northeast United States.

Used in a graphical analysis of a joist or joist girder. It is a notation for denoting truss joints, members, loads, and forces. Capital letters are placed in the spaces between truss members and between forces. Each member and load is then designated by the letters on opposite sides of it.

A mechanical instrument usually having a pair of pivoted legs adjustable to any distance and used to measure thichness, distances between surfaces, and any internal or external diameter which is inaccessible with a scale.

A welder who has been certified by a competent experienced welding inspector or a recognized testing facility in the field of welding. The welder must be certified to make certain welds under qualified procedures. The welder must be qualified for each position, type weld, electrode, and thickness of base metal that is to be welded in the shop or field.

Is a main vertical member carrying axial loads, which can be combined with bending and shear, from the main roof beams or girders to the foundation. These structural members carry loads parallel to its longitudinal axis.

A steel section whose flanges must be continuously connected to the webs and the width-thickness ratios of its compression element can not exceed the limiting width-thichness ratios designated in the AISC Manual.

A regular angel whose ends have been 'crimped' in the shape of a 'U' whose out-to-out distance is usually one inch. The actual crimped portion of the angle is only a few inches on each end and the end is inserted between top or bottom chord members to be welded.

Two angles or other structural shapes connected from the top chord of one joist to the bottom chord of the next joist to form an 'X' shape whose l/r ratio cannot exceed 200. The bridging members are almost always connected at their point of intersection.

1) A structural angle that is connected around the edge of a joist extension or other member 2) An angle used around the sides of a floor to contain the concrete when it is being poured which is also called a Pour Stop.

The equivalent length, KL, used in compression formulas. This method estimates the interaction effects of the total frame on a compression member by using K factors to equate the strength of a framed compression member of length L to an equivalent pin-ended member of length KL subject to axial load only.

The ratio between the effective length and the unbraced length of a member measured between center of gravities of the bracing members. K values are given for several idealized conditions in which joint rotation and translation are realized.

The equations relating a state of static equilibrium of a member or structure when the resultant of all forces and moments are equal to zero. Three equations must be fulfilled simultaneously: Sum of the forces in the X-direction must equal zero, sum of the forces in the Y-direction must equal zero, and the sum of the moments about any point must equal zero for a two dimensional structure.

Floor or roof plans that identify individual marks, components, and accessories furnished by the joist manufactures in a detailed mannner to permit proper erection of the joist and joist girders. See Framing Plan and Placing Plan.

The extended part of a joist top chord with also the seat angles extended from the end of the jost extension back into the joist maintaining the standard 2 1/2 inch end bearing depth over the entire length of the extension.

The ability of a joist or other structural member to resist a fire due to the type of protection it has, such as membrane protection or spray on protection. There are hundreds of floor-ceiling or roof-ceiling assemblies with their fire-resistance rating given in the Underwriters Laboratory Fire Directory.

A condition where no rotation or horizontal or vertical movement can occur at that end. This type of support has no degrees of freedom. Three reactive forces exist at the rigidly fixed end. See also Rigid Connection.

A structural framing system consisting of members joined together with moment or rigid connections which maintain their original angular relationship under load without the need for bracing in its plane. See Rigid Frame.

Floor or roof plans that identify individual marks, components, and accessories furnished by the joist manufactures in a detailed mannner to permit proper erection of the joist and joist girders. See Erection Plan and Placing Plan.

A structural member located between two joists or between a joist and a wall which carries another joist or joists. Usually made up of an angle, channel, or beam with saddle angle connections on each end for bearing.

This type of support has one degree of freedom, it can freely rotate about its axis but it cannot displace in any direction. Two mutually perpendicular reactive forces exist at the hinge and their lines of action pass through the center of the hinge. See Pin Connection or Support.

Formula: Horizontal Shear stress (in psi)=(V * Q)/I*t, where 'V' is the external vertical shear on the section in lbs, 'I' is the moment of inertia of the section in inches^4, 'Q' is the statical moment about the neutral axis of the entire section of that portion of the cross-section lying outside of the cutting plane and 't' is the width at the cutting plane.

A term that describes the behavior of a structural member subjected to reversed, repeated load into the inelastic range whose plot of load verses displacement is characterized by loops. The amount of energy dissipated during inelastic loading is indicated by the enclosed area within these loops.

An influence line is a curve whose ordinates give the values of some particular function (shear, moment, reaction, etc.) in an element due to a unit load acting at the point corresponding to the particular ordinate being considered. Influence lines for statically determinate structures are straight lines and for statically indeterminate structures the lines are curved and their construction involves considerable analysis.

A standard way of communicating the joist safe uniformly distributed load-carrying capacities for a given span such as 16K5 or 24K10 where the first number is the nominal joist depth at midspan and the last number is the chord size. See Longspan Designation and Joist Girder Designation.

A primary structural load-carrying member with an open web system designed as a simple span supporting equally spaced concentrated loads of a floor or roof system acting at the panel points of the joist girder and utilizing hot-rolled or cold-formed steel.

A standard way of communicating the girder design loads such as 48G6N10.5K where the first number is the nominal girder depth at midspan, 6N is the number of joist spaces on the span of girder, and 10.5K is the kip load on each panel point of the girder. The approximate dead load weight of the member is included in the kip load. See Joist Designation and Longspan Designation.

A structural member which is intended for use at very short spans (10 feet or less) where open web steel joists are impractical. They are usually used for short spans in skewed bays, over corridors, or for outriggers. It can be made up of two or four angles to form channel sections or box sections. See Angle Unit.

A small reference plan or outline of the whole building on each plan sheet divided into smaller areas for which each sheet is drawn. It can also show different sequences, phases, sheet number that area is drawn on, etc.

Loads on a member that are not permanent and are likely to be moved at some point in the life of the structure. They can be loads produced by the use and occupancy of the building. These loads do not include dead load, wind load, snow load, or seismic load.

A table of standard joist designations which give the total safe uniformly distributed load-carrying capacities and live load-carring capacities of the joists for different span lengths. The table also gives the approximate weight per foot of each joist designation.

A diagram which shows all design loads and design criteria that a member is to be designed for. The loads include: dead load, live load, snow drift, concentrated loads, moments, etc. The design criteria include: deflection requirements, load combinations, net uplift, one-third increase in allowable stress allowed or not, etc.

A standard way of communicating the longspan joist safe uniformly distributed load-carrying capacities for a given clear span such as 18LH06 or 36LH10 where the first number is the nominal joist depth at midspan and the last number is the section number. See Joist Designation and Joist Girder Designation.

A structural load-carrying member with an open web system which supports floors and roofs utilizing hot-rolled or cold-formed steel and is designed as a simple span member. These carry higher loads than a regular joist.

An identification number or method of relating to the erector which joist, joist girder or other separate part of the building goes at what location when being erected, i.e., J1, K25, L7, G12, or JG9. See Piece Mark and Part Number.

An idealization to model how members are attached to "each other". It designates whether forces and moments at the ends of a member are considered fixed to or released from the member's point of attachment.

A building system consisting of a group of coordinated components which have been designed for a certain loading. These components are mass produced and assembled in various combinations with other structural materials to produce a building.

Is a not-for-profit organization which was formed to advance the interests of the material handling industry which includes the movement, storage, control, and protection of material and products throughout the process of their manufacture, distribution, consumption, and disposal.

A report of a heat of steel that indicates the customer's order number, grade of steel, number and dimensions of pieces shipped, and the chemical compositional makeup of hot rolled structural steel members. It also indicates physical properties, such as, yield strength, tensile strength, elongation, impact, and ultimate strength.

Is the slope of the straight-line portion of the stress-strain curve in the elastic range found by dividing the unit stress in ksi by the unit strain in in/in. For all structural steels, the value is usually taken as 29,000 ksi. This is also called Young's Modulus.

A minimum model regulatory code for the protection of public health, safety, welfare and property by regulating and controlling the design, construction, quality of materials, use, occupancy, location and maintenance of all buildings and structures within a jurisdiction.

A structural member which is usually perpendicular to a joist and attaches under the outstanding leg of one of the joist top chord angles. It then bears on a beam or wall and cantilevers across, similar to a top chord extension.

A connection where no moment is transfered from one member to another, only axial and shear forces. This type of support has one degree of freedom, it can freely rotate about its axis but it cannot displace in any direction. Two mutually perpendicular reactive forces exist at the pin and their lines of action pass through the center of the pin. See Hinge Support.

A structural system where two joists are used to carry loads such as piping or ducts. The two joists have to have diagonal bridging and their top and bottom chords have to be laced together with structural members to provide stability for the whole structure,

Is the slope or inclination of a member. It is defined as the ratio of the total rise to the total width. It also is defined as the angle that the top chord makes with the lower chord. There can be single or double pitched members.

Defined as the ratio of the unit lateral strain to the unit longitudinal strain. It is constant for a material within the elastic range. For structural steel, the value is usually taken as 0.3. It gradually increases beyond the proportional limit, approaching 0.5.

A structural framing system consisting of members joined together with moment or rigid connections which maintain their original angular relationship under load without the need for bracing in its plane. See Frame and Stability.

An institute organized in 1958 by industry leaders as a not-for-profit trade association. Its mission is to advance standards, quality, safety, and general fitness for intended use of industrial steel storage rack systems.

This type of support has two degrees of freedom, it can freely rotate about its axis or displace in one direction in the plane. Only one reactive force exists at a roller which acts perpendicular to the path of the displacement and its line of action passes through the center of the roller.

The angle connection or seat on the end of a header or frame which bears from the side on the top chord of a joist. This angle should be designed to carry the reaction of the header or frame to the center of the joist and must rest on and weld to both top chord angles.

A minimum model regulatory code for the protection of public health, safety, welfare and property by regulating and controlling the design, construction, quality of materials, use, occupancy, location and maintenance of all buildings and structures within a jurisdiction.

A physical property of strength of a structural member. It relates bending moment and maximum bending stress within the elastic range. Formula: S=I/c where 'I' is the moment of inertia of the cross-section about the neutral axis in inches^4 and 'c' is the distance from the neutal axis to the outermost fibers.

The institute is a non-profit organization of active joist manufacturers that maintains sound engineering practice throughout the joist industry. The institute coopera Wtes with business and government agencies to establish steel joist standards and does continuing research of their products to maintain the integrity of their products.

A system for fire protection usually consisting of overhead piping connected to a water supply to which automatic sprinklers are attached that discharges water in a specific pattern for extinguishment or control of a fire.

A type of roof system where the deck is attached to clips which are then attached to the beam or joist. Usually this type of roof system cannot be counted on to provide lateral stability or support to the joist top chord.

A member or structure that cannot be analyzed soley by the equations of statics. It contains unknowns in excess of the number of equilibrium equations available. Additional equations must be written based on a knowledge of elastic deformations.

A large number of steels that are suitable for load-carrying members in a variety of structures because of strength, economy, ductility, and other properties. Strength levels are obtained by varying the chemical composition and by heat treatment.

This is the end of a joist or joist girder where an identification or piece mark is shown by a metal tag. The member must be erected with this tagged end in the same position as the tagged end noted on the erection plan.

In general, a structural load-carrying member with an open web system designed as a simple span with each member designed to carry a tension or compression force. The entire structure act will act like a beam.

A minimum model regulatory code for the protection of public health, safety, welfare and property by regulating and controlling the design, construction, quality of materials, use, occupancy, location and maintenance of all buildings and structures within a jurisdiction.

The wind load on a member which causes a load in the upward direction. The gross uplift is determined from various codes and is generally a horizontal wind pressure multiplied by a factor to establish the uplift pressure. The net uplift is the gross uplift minus the allowable portion of dead load including the weight of the joist and is the load that the specifying professional shall indicate to the joist manufacturer.

A structural design method whereby a structural element is designed so that the unit stresses computed under the action of working or service loads do not exceed the specified allowable values. See Allowable Stress Design and Elastic Design.

A member used as a joist substitute which is intended for use at very short spans (10 feet or less) where open web steel joists are impractical. They are usually used for short spans in skewed bays, over corridors, or for outriggers. It can be made up of two or four angles to form channel sections or box sections. Tube and channel sections are also used. See Joist Substitute.

A minimum model regulatory code for the protection of public health, safety, welfare and property by regulating and controlling the design, construction, quality of materials, use, occupancy, location and maintenance of all buildings and structures within a jurisdiction. Its serves primarily the North Central and Northeast United States.

A welder who has been certified by a competent experienced welding inspector or a recognized testing facility in the field of welding. The welder must be certified to make certain welds under qualified procedures. The welder must be qualified for each position, type weld, electrode, and thickness of base metal that is to be welded in the shop or field.

The equations relating a state of static equilibrium of a member or structure when the resultant of all forces and moments are equal to zero. Three equations must be fulfilled simultaneously: Sum of the forces in the X-direction must equal zero, sum of the forces in the Y-direction must equal zero, and the sum of the moments about any point must equal zero for a two dimensional structure.

Formula: Horizontal Shear stress (in psi)=(V * Q)/I*t, where 'V' is the external vertical shear on the section in lbs, 'I' is the moment of inertia of the section in inches^4, 'Q' is the statical moment about the neutral axis of the entire section of that portion of the cross-section lying outside of the cutting plane and 't' is the width at the cutting plane.

An influence line is a curve whose ordinates give the values of some particular function (shear, moment, reaction, etc.) in an element due to a unit load acting at the point corresponding to the particular ordinate being considered. Influence lines for statically determinate structures are straight lines and for statically indeterminate structures the lines are curved and their construction involves considerable analysis.

A standard way of communicating the girder design loads such as 48G6N10.5K where the first number is the nominal girder depth at midspan, 6N is the number of joist spaces on the span of girder, and 10.5K is the kip load on each panel point of the girder. The approximate dead load weight of the member is included in the kip load. See Joist Designation and Longspan Designation.

A diagram which shows all design loads and design criteria that a member is to be designed for. The loads include: dead load, live load, snow drift, concentrated loads, moments, etc. The design criteria include: deflection requirements, load combinations, net uplift, one-third increase in allowable stress allowed or not, etc.

A report of a heat of steel that indicates the customer's order number, grade of steel, number and dimensions of pieces shipped, and the chemical compositional makeup of hot rolled structural steel members. It also indicates physical properties, such as, yield strength, tensile strength, elongation, impact, and ultimate strength.

A connection where no moment is transfered from one member to another, only axial and shear forces. This type of support has one degree of freedom, it can freely rotate about its axis but it cannot displace in any direction. Two mutually perpendicular reactive forces exist at the pin and their lines of action pass through the center of the pin. See Hinge Support.

The institute is a non-profit organization of active joist manufacturers that maintains sound engineering practice throughout the joist industry. The institute coopera Wtes with business and government agencies to establish steel joist standards and does continuing research of their products to maintain the integrity of their products.

The wind load on a member which causes a load in the upward direction. The gross uplift is determined from various codes and is generally a horizontal wind pressure multiplied by a factor to establish the uplift pressure. The net uplift is the gross uplift minus the allowable portion of dead load including the weight of the joist and is the load that the specifying professional shall indicate to the joist manufacturer.

Abutment - the outermost end supports on a bridge, which carry the load from the deck

Aluminum - a lightweight chemical element (Al); the most abundant metallic element in the Earth's crust

Anchorage - a secure fixing, usually made of reinforced concrete to which the cables are fastened

Aqueduct - a bridge or channel for conveying water, usually over long distances

Arch Bridge - a curved structure that converts the downward force of its own weight, and of any weight pressing down on top of it, into an outward force along its sides and base

Arch Dam - a dam with an arched shape that resists the force of water pressure; requires less material than a gravity dam for the same distance

Architect -a person who designs all kinds of structures; must also have the ability to conceptualize and communicate ideas effectively -- both in words and on paper -- to clients, engineers, government officials, and construction crews

Beam - a rigid, usually horizontal, structural element

Beam Bridge - a simple type of bridge, composed of horizontal beams supported by vertical posts

Bedrock -the solid rock layer beneath sand or silt

Bend - (v.) to curve; bending occurs when a straight material becomes curved; one side squeezes together in compression, and the other side stretches apart in tension

Bends - (n.) see caisson disease

Brace - (n.) a structural support; (v.) to strengthen and stiffen a structure to resist loads

Brittle -characteristic of a material that fails without warning; brittle materials do not stretch or shorten before failing

Buckle - to bend under compression

Buttress - a support that transmits a force from a roof or wall to another supporting structure

Buttress Dam - a gravity dam reinforced by structural supports

Cable - a structural element formed from steel wire bound in strands; the suspending element in a bridge; the supporting element in some dome roofs

Cable-Stayed Bridge -a bridge in which the roadway deck is suspended from cables anchored to one or more towers

Caisson -a watertight, dry chamber in which people can work underwater

Caisson Disease -an affliction developed by people moving in and out of caissons quickly; also called the bends and decompression sickness

Cantilever -a projecting structure supported only at one end, like a shelf bracket or a diving board

Cast Iron - a brittle alloy with high carbon content; iron that has been melted, then poured into a form and cooled; can be made into any shape desired

Civil Engineer -an engineer who plans, designs, and supervises the construction of facilities essential to modern life

Cement -a binding material, or glue, that helps concrete harden

Coffer -a sunken panel in a ceiling

Cofferdam -a temporary dam built to divert a river around a construction site so the dam can be built on dry ground

Column - a vertical, structural element, strong in compression

Compressed-Air Chamber -the space at the bottom of a caisson into which air is introduced under pressure to exclude water so that excavation can take place

Compression - a pressing force that squeezes a material together

Concrete -a mixture of water, sand, small stones, and a gray powder called cement

Construction Manager -a person who coordinates the entire construction process -- from initial planning and foundation work through the structure's completion

Continuous Span Beam Bridge -simple bridge made by linking one beam bridge to another; some of the longest bridges in the world are continuous span beam bridges

Core -central region of a skyscraper; usually houses elevator and stairwell

Cut and Cover -a method of tunnel construction that involves digging a trench, building a tunnel, and then covering it with fill

Deck -supported roadway on a bridge

Deform -to change shape

Diversion Channel -a bypass created to divert water around a dam so that construction can take place

Dome -a curved roof enclosing a circular space; a three-dimensional arch

Downstream Face -the side of the dam that is not against the water

Dynamite -a blasting explosive, based on nitroglycerin, but much safer to handle than nitroglycerin alone

Electrical Engineer -an engineer concerned with electrical devices and systems and with the use of electrical energy

Embankment Dam -a dam composed of a mound of earth and rock; the simplest type of gravity dam

Engineering -a profession in which a knowledge of math and natural science is applied to develop ways to utilize the materials and forces of nature for the benefit of all human beings

Environmental Engineer -an engineer who designs and operates systems to provide safe drinking water and to prevent and control pollution in water, in the air, and on the land

Fire-Setting -an ancient tunneling technique in which rock is heated with fire and then doused with cold water, causing the rock to fracture

Force - any action that tends to maintain or alter the position of a structure

Geodesic Dome -a dome composed of short, straight pieces joined to form triangles; invented by Buckminster Fuller

Geotechnical Engineer -an engineer who evaluates and stabilizes foundations for buildings, roads, and other structures

Gravity Dam -a dam constructed so that its great weight resists the force of water pressure

Gunpowder -any of several low-explosive mixtures used as a blasting agent in mining and tunneling; the first such explosive was black powder, which consists of a mixture of potassium nitrate, sulfur, and charcoal

Iron -a chemical element (Fe); one of the cheapest and most used metals

Joint - a device connecting two or more adjacent parts of a structure; a roller joint allows adjacent parts to move controllably past one another; a rigid joint prevents adjacent parts from moving or rotating past one another

Load - weight distribution throughout a structure; loads caused by wind, earthquakes, and gravity, for example, affect how weight is distributed throughout a structure

Masonry - a building material such as stone, clay, brick, or concrete

Mechanical Engineer -an engineer who applies the principles of mechanics and energy to the design of machines and devices

Monolithic Dome -a dome composed of a series of arches, joined together with a series of horizontal rings called parallels

Movable Bridge -a bridge in which the deck moves to clear a navigation channel; a swing bridge has a deck that rotates around a center point; a drawbridge has a deck that can be raised and lowered; a bascule bridge deck is raised with counterweights like a drawbridge; and the deck of a lift bridge is raised vertically like a massive elevator

Nitroglycerin -an explosive compound made from a mixture of glycerol and concentrated nitric and sulfuric acids, and an important ingredient of most forms of dynamite

Perimeter -the distance around the outside of a shape

Pier -a vertical supporting structure, such as a pillar

Pendentive -a triangular shape that adapts the circular ring of a dome to fit onto a flat supporting wall

Pile - a long, round pole of wood, concrete, or steel driven into the soil by pile drivers

Pile Driver -a noisy machine that repeatedly drops a heavy weight on top of a pile until the pile reaches solid soil or rock or cannot be pushed down any farther

Plastic -a synthetic material made from long chains of molecules; has the capability of being molded or shaped, usually by the application of heat and pressure

Pressure - a force applied or distributed over an area

Reinforced Concrete - concrete with steel bars or mesh embedded in it for increased strength in tension; in pre-tensioned concrete, the embedded steel bars or cables are stretched into tension before the concrete hardens; in post-tensioned concrete, the embedded steel bars or cables are stretched into tension after the concrete hardens

Richter Scale -used to measure the magnitude of an earthquake; introduced in 1935 by the seismologists Beno Gutenberg and Charles Francis Richter

Rigid - (adj.) ability to resist deformation when subjected to a load; rigidity (n.) the measure of a structure's ability not to change shape when subjected to a load

Rock Tunnel - a passage constructed through solid rock

Shear - a force that causes parts of a material to slide past one another in opposite directions

Shear-Walls - solid concrete walls that resist shear forces; often used in buildings constructed in earthquake zones

Silt - sediment particles ranging from 0.004 to 0.06 mm (0.00016 to 0.0024 inch) in diameter

Soft-Ground Tunnels -a passage constructed through loose, unstable, or wet ground, requiring supports to keep the walls from collapsing

Span -(n.) the distance a bridge extends between two supports; (v.) to traverse a specific distance

Spillway -an overflow channel that allows dam operators to release lake water when it gets high enough to threaten the safety of a dam

Spire -an architectural or decorative feature of a skyscraper; the Council on Tall Buildings and Urban Habitat includes spires but not antennae when calculating the official height of a skyscraper

Stable -(adj.) ability to resist collapse and deformation; stability (n.) characteristic of a structure that is able to carry a realistic load without collapsing or deforming significantly

Steel - an alloy of iron and carbon that is hard, strong, and malleable

Stiff - (adj.) ability to resist deformation; stiffness (n.) the measure of a structure's capacity to resist deformation

Story -floor of a skyscraper

Strong - (adj.) ability to carry a realistic load; strength (n.) the measure of a structure's ability to carry a realistic load

Structural Engineer -an engineer who investigates the behavior and design of all kinds of structures, including dams, domes, tunnels, bridges, and skyscrapers, to make sure they are safe and sound for human use

Suspension Bridge - a bridge in which the roadway deck is suspended from cables that pass over two towers; the cables are anchored in housings at either end of the bridge

Tailings Dam -a dam, usually made of earth and rock, used to contain mining waste

Tensegrity -an array of tension cables and compression rods that supports a structure; invented by Buckminster Fuller student Kenneth Snellson

Tension - a stretching force that pulls on a material

Tension Ring -a support ring that resists the outward force pushing against the lower sides of a dome

Torsion -an action that twists a material

Tower -the vertical structure in a suspension bridge or cable-stayed bridge from which cables are hung; also used loosely as a synonym for the term skyscraper

Truss - a rigid frame composed of short, straight pieces joined to form a series of triangles or other stable shapes

Tuned Mass Damper -a mechanical counterweight designed to reduce the effects of motion, such as the swaying of a skyscraper in the wind or in an earthquake

Tunnel Boring Machine (TBM) -a mechanical device that tunnels through the ground

Tunnel Shield -a cylinder pushed ahead of tunneling equipment to provide advance support for the tunnel roof; used when tunneling in soft or unstable ground

Unstable -characteristic of a structure that collapses or deforms under a realistic load

Upstream Face -the side of a dam that is against the water

Wood -a common natural material strong in both compression and tension

Wrought Iron -an iron alloy that is less brittle than cast iron

a curved structure that converts the downward force of its own weight, and of any weight pressing down on top of it, into an outward force along its sides and base

a dam with an arched shape that resists the force of water pressure; requires less material than a gravity dam for the same distance

a person who designs all kinds of structures; must also have the ability to conceptualize and communicate ideas effectively -- both in words and on paper -- to clients, engineers, government officials, and construction crews

(v.) to curve; bending occurs when a straight material becomes curved; one side squeezes together in compression, and the other side stretches apart in tension

characteristic of a material that fails without warning; brittle materials do not stretch or shorten before failing

a structural element formed from steel wire bound in strands; the suspending element in a bridge; the supporting element in some dome roofs

an affliction developed by people moving in and out of caissons quickly; also called the bends and decompression sickness

a brittle alloy with high carbon content; iron that has been melted, then poured into a form and cooled; can be made into any shape desired

the space at the bottom of a caisson into which air is introduced under pressure to exclude water so that excavation can take place

a person who coordinates the entire construction process -- from initial planning and foundation work through the structure's completion

simple bridge made by linking one beam bridge to another; some of the longest bridges in the world are continuous span beam bridges

a method of tunnel construction that involves digging a trench, building a tunnel, and then covering it with fill

a profession in which a knowledge of math and natural science is applied to develop ways to utilize the materials and forces of nature for the benefit of all human beings

an engineer who designs and operates systems to provide safe drinking water and to prevent and control pollution in water, in the air, and on the land

an ancient tunneling technique in which rock is heated with fire and then doused with cold water, causing the rock to fracture

any of several low-explosive mixtures used as a blasting agent in mining and tunneling; the first such explosive was black powder, which consists of a mixture of potassium nitrate, sulfur, and charcoal

a device connecting two or more adjacent parts of a structure; a roller joint allows adjacent parts to move controllably past one another; a rigid joint prevents adjacent parts from moving or rotating past one another

weight distribution throughout a structure; loads caused by wind, earthquakes, and gravity, for example, affect how weight is distributed throughout a structure

a bridge in which the deck moves to clear a navigation channel; a swing bridge has a deck that rotates around a center point; a drawbridge has a deck that can be raised and lowered; a bascule bridge deck is raised with counterweights like a drawbridge; and the deck of a lift bridge is raised vertically like a massive elevator

an explosive compound made from a mixture of glycerol and concentrated nitric and sulfuric acids, and an important ingredient of most forms of dynamite

a noisy machine that repeatedly drops a heavy weight on top of a pile until the pile reaches solid soil or rock or cannot be pushed down any farther

a synthetic material made from long chains of molecules; has the capability of being molded or shaped, usually by the application of heat and pressure

concrete with steel bars or mesh embedded in it for increased strength in tension; in pre-tensioned concrete, the embedded steel bars or cables are stretched into tension before the concrete hardens; in post-tensioned concrete, the embedded steel bars or cables are stretched into tension after the concrete hardens

used to measure the magnitude of an earthquake; introduced in 1935 by the seismologists Beno Gutenberg and Charles Francis Richter

(adj.) ability to resist deformation when subjected to a load; rigidity (n.) the measure of a structure's ability not to change shape when subjected to a load

a passage constructed through loose, unstable, or wet ground, requiring supports to keep the walls from collapsing

an overflow channel that allows dam operators to release lake water when it gets high enough to threaten the safety of a dam

an architectural or decorative feature of a skyscraper; the Council on Tall Buildings and Urban Habitat includes spires but not antennae when calculating the official height of a skyscraper

(adj.) ability to resist collapse and deformation; stability (n.) characteristic of a structure that is able to carry a realistic load without collapsing or deforming significantly

(adj.) ability to resist deformation; stiffness (n.) the measure of a structure's capacity to resist deformation

(adj.) ability to carry a realistic load; strength (n.) the measure of a structure's ability to carry a realistic load

an engineer who investigates the behavior and design of all kinds of structures, including dams, domes, tunnels, bridges, and skyscrapers, to make sure they are safe and sound for human use

a bridge in which the roadway deck is suspended from cables that pass over two towers; the cables are anchored in housings at either end of the bridge

an array of tension cables and compression rods that supports a structure; invented by Buckminster Fuller student Kenneth Snellson

the vertical structure in a suspension bridge or cable-stayed bridge from which cables are hung; also used loosely as a synonym for the term skyscraper

a mechanical counterweight designed to reduce the effects of motion, such as the swaying of a skyscraper in the wind or in an earthquake

a cylinder pushed ahead of tunneling equipment to provide advance support for the tunnel roof; used when tunneling in soft or unstable ground

a person who designs all kinds of structures; must also have the ability to conceptualize and communicate ideas effectively -- both in words and on paper -- to clients, engineers, government officials, and construction crews

a device connecting two or more adjacent parts of a structure; a roller joint allows adjacent parts to move controllably past one another; a rigid joint prevents adjacent parts from moving or rotating past one another

a bridge in which the deck moves to clear a navigation channel; a swing bridge has a deck that rotates around a center point; a drawbridge has a deck that can be raised and lowered; a bascule bridge deck is raised with counterweights like a drawbridge; and the deck of a lift bridge is raised vertically like a massive elevator

concrete with steel bars or mesh embedded in it for increased strength in tension; in pre-tensioned concrete, the embedded steel bars or cables are stretched into tension before the concrete hardens; in post-tensioned concrete, the embedded steel bars or cables are stretched into tension after the concrete hardens

a bridge in which the deck moves to clear a navigation channel; a swing bridge has a deck that rotates around a center point; a drawbridge has a deck that can be raised and lowered; a bascule bridge deck is raised with counterweights like a drawbridge; and the deck of a lift bridge is raised vertically like a massive elevator

Glossary :

2D: A graphic representation that shows only two of an object's dimensions at one time, such as height and width, or width and depth, or height and depth.

3D: A graphic representation that shows all three dimensions of an object at one time: height, width, and depth.

3D modeling (computer): A computer-based modeling system that allows the designer to create model geometry on an x-, y-, and z-axis system.

A

A-frame: A structure, such as a house, with steeply angled sides that meet at the top in the shape of the letter A.

Above ground: Term applied to any utility that is brought into a property situated or taking place on or above the surface of the ground.

Absorption: The process whereby one substance is physically taken into and included within another substance, as the absorption of water by soil.

Adjacency matrix: A matrix used to clarify the design parameters for the client by rating components of a project based on most desirable features and placement.

Aesthetics: Of or concerning how pleasing something is to the senses.

Alluvium: Clay, silt, gravel, or similar material deposited by running water.

Ampere: A measure of electrical current flow.

Anaerobic: Growing in the absence of oxygen, as in anaerobic bacteria in a septic tank.

Analyzed: Examined carefully and methodically; broken down for consideration of constituent parts.

Angle of Repose: The angle, measured from the horizontal, that granular material is stable while unsupported.

Architect: A person who designs and supervises the construction of buildings or other large structures.

Architecture: The profession of designing buildings and environments with consideration for their aesthetic effect.

Architectural styles: The design element of a structure that is identified by the distinguishing characteristics of the exterior.

Arterial: Roads that carry between 400 to 800 cars per lane per hour depending on businesses, parking, signs, and control signals.

Aquifer: An underground geological formation or group of formations containing usable amounts of groundwater that can supply wells and springs.

Artifact: An object produced or shaped by human craft, especially a tool, weapon, or ornament of archeological or historical interest.

Asymmetry: Lack of balance or symmetry.

Attorney: A person legally appointed by another to act as his or her agent in the transaction of business, specifically one qualified and licensed to act for plaintiffs and defendants in legal proceedings.

Azimuth: The horizontal angle reckoned clockwise from the north or south meridian.

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B

Backsight (BS): The reference point from which horizontal angles, vertical and horizontal differences are measured.

Baffle: A shield usually made of scrap material to keep insulation from plugging eave vents; also used to describe wind- or sound-deadening devices.

Balance: A principle of design dealing with the relationship between the various areas of a structure as they relate to an imaginary centerline; sometimes referred to as symmetrical or equally proportioned.

Barrier: Soil or vegetation blocking sound or sight lines.

Beam: A horizontal structural member that is used to support roofs or wall loads, such as a header.

Bearing points: A property boundary location identified by the distance from a fixed point and at an angle and direction relative to that point.

Bearings: would indicate a direction that is 56-degrees, 45-minutes from the south to the west. Directions with reference to one quadrant of a compass used to identify property boundaries in the metes and bounds system. Example: (S 56° 45' W)

Begin Vertical Curve (BVC): On an engineering drawing, the point at which the road transitions from an even slope to a vertical curve.

Benchmark: A known reference point or location of known or assumed elevation and/or horizontal coordinates.

Bending: One of three major forces acting on a beam. It is the tendency of a beam to bend or sag between its supports.

Bending moment: A measure of the forces that cause a beam to break by bending. Represented by (M).

Bentonite: 1. A very fine grained clay formed from decayed glass particles in volcanic rock which forms a watertight bond when compacted. One form of it, Sodium Bentonite, absorbs water and swells to about 20 times its original size. The other, Calcium Bentonite, does not change size. Bentonites are generally used to seal dump sites, pond bottoms and other areas used to contain water or chemicals. 2. An absorbent aluminum silicate clay formed from volcanic ash and used in various adhesives, cements, and ceramic fillers.

Berm: Mound of earth used as a barrier.

Bird's mouth: A notch cut into a rafter to provide a bearing surface where the rafter intersects the top plate.

Blocking: Framing members, typically wood, placed between joist, rafters, or studs to provide rigidity (also called bridging).

Blueprints: A generally accepted term for a set of printed drawings created by the Diazo reproduction process. Original blueprints were created by a wet chemical process that caused the background to be blue and any lines or printing to be white.

Body Language: The gestures, postures, and facial expressions by which a person manifests various physical, mental, or emotional states and communicates nonverbally with others.

Bottom plate: The lowest horizontal framing member used in residential wall construction.

Boxes: A metal or plastic container equipped with clamps, used to terminate a conduit. Also known as an outlet box.

Bracing System: A method of reinforcing a structure to resist lateral loads.

Branch: A pipe or conduit that splits from a main to carry a utility to a group of structures.

Broadleaf: Plants having relatively broad rather than needle-like or scar-like leaves.

Bounds: A limit, "boundary" as used in the Metes and Bounds system for the legal description of property.

Bubble diagrams: Freehand sketches used to determine room locations, flow of traffic, and spatial relationships. They are the first step in the design process used to represent spatial relationships and placement of circulation flow.

Building Codes: Legal requirements designed to protect the public by providing guidelines for structural, electrical, plumbing, and mechanical areas of a structure.

Building Inspectors: Individuals who inspect new construction to make sure that the methods and materials meet local and national code requirements.

Building section: A type of drawing showing an object as if it had been cut through from the peak of the roof to the base of the foundation in order to show interior construction.

Building Structure: The arrangement of parts to form a whole. A building structure's primary function is to support and redirect loads and forces safely to the ground. It constantly withstands forces of wind, effects of gravity, vibrations, and sometimes earthquakes.

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C

Caisson: A watertight structure within which construction work is carried on under water.

Cantilever: Projected construction that is fastened at only one end.

Cantilever beam: A long piece of wood or metal used to support a structure; a horizontal beam that is fastened only at one end and extends beyond a supporting surface.

Cartography: The study of map making.

Cartographic surveying: Plotting the points necessary to make a map.

Cast iron: A heavy metal pipe typically used to convey potable water supplies.

Catchbasin: A device used to capture sediment, nutrients, metals, and hydrocarbons suspended in runoff from impervious surfaces before being conveyed to a storm sewer network or to another water-quality treatment system.

Ceiling: The upper interior surface of a room.

Ceiling joist: The horizontal member of the roof which is used to resist the outward spread of the raters and to provide a surface on which to mount the finished ceiling.

Chipboard: A flat construction material, made by using flat chips of wood bonded with formaldehyde glue; sometimes referred to as wafer board; term used in the construction industry for Oriented Strand Board (OSB). OSB was developed as an inexpensive replacement for plywood. It comes in several thicknesses only some of which are rated for sheathing or decks.

Chord: The upper and lower members of a truss which are supported by the web.

Circuit: The various conductors, connections, and devices found in the path of electrical flow from the source through the components and back to the source.

Circuit Breaker: An electrical safety switch that automatically opens a circuit when excessive amperage occurs.

Circulation: Overall flow of people and goods on a site.

Civil engineer: A person trained in the design and construction of public works projects, such as highways, bridges, sanitation facilities, and water treatment plants.

Clamp screw: A mechanism that locks a surveying instrument in a horizontal or vertical position.

Clean-out: A special fitting that allows access to drainage lines for removing obstructions that develops in those lines.

Client: A person who employs another professionally; a customer.

Closed Traverse: A collection of Traverse lines that return to the POB (Point of Beginning) or other Control Point; the boundaries of a property.

Codes: A body of laws regulating land use, development, and construction.

Collar: Horizontal ties between rafters near the ridge to help resist the tendency of the rafters to separate.

Collectors: Local roads that can generally carry 100-250 cars per lane per hour.

Colloidal: Made up of very small particles, which remain suspended in water. A typical example is clays.

Color: An integral part of design and decorating which helps distinguish exterior materials and accents shapes.

Columns: Vertical, beam members which are responsible for supporting compressive loads and transferring those loads to the foundation of a structure.

Commercial Structure: Any building intended for carrying out a business or service.

Common practices: Procedures that are widely accepted by a group of people as the preferred way to accomplish certain tasks.

Community: Organized political or social body; a body of people in the same locality.

Competitions: Contests used to show or expose work to different forms of evaluation and comparisons to alternate solutions.

Complex beam: Beam with a non-uniform load at any point on it, having supports that are not located at its end.

Component: A part of a mechanical or electrical complex.

Compression: A force that crushes or compacts.

Conclusion: The close or last part; the end or finish.

Conductor: Any material that permits the flow of electricity.

Construction Management Engineering: A profession that is responsible for managing and providing quality control, reviewing contracts, ordering materials, and hiring and scheduling sub-contractors for a structural engineering job.

Constructive criticism: Comments serving to improve or advance; providing a helpful critical judgment expressed with knowledge.

Consumption-Based Methodology: One of two suggested systems that can be used to establish utility allowances. (See also engineering-based methodology.) This method is based on actual consumption data from utility bills or checked meter readings. Data is used to estimate the amount of energy or water a household should reasonably require.

Continuous beam: A beam having three or more supports.

Continuous foundation: A base on which something rests; poured or fabricated in one complete form, such as a concrete foundation.

Contour: Lines on a map showing the topographical outlines of the physical characteristics of the land or a line that joins points of similar elevation.

Contour Interval: The elevation change between adjacent contours.

Contractor: A person responsible for directing a project or a portion of the work on a project as in the case of a subcontractor; usually a legally binding agreement is signed and a bond posted to ensure completion.

Control: Any station for which position coordinates and/or elevation is already known, and from which the positions or elevations of unknown stations are determined.

Cooling Degree Days: A measure of the severity of the summer in a given locality: the more cooling degree days, the hotter the summers. Cooling degree days (CDD) are the difference between 65 degrees F and the daily mean (average) temperature when the latter is more than 65 degrees F.

Coordinate geometry: A mathematical system that locates points using x- and y-values and angles.

Corner post: The built up vertical section of wall framing used to provide stability and nailing surface at the intersection of wall sections.

Cornice: The part of the roof that extends out from the wall; sometimes referred to as the eave.

Covenants: Binding agreements that list restrictions for the use of property by its owners.

Cripple stud: An upright piece of wood that is cut at less than full length used in wall construction

Critical buckling load: Large compression load that causes a column to become unstable, resulting in a sudden lateral deflection of the column.

Critique: A critical review or commentary.

Cross bracing: Boards fastened diagonally between structural members, such as floor joists, to provide rigidity.

Culture: Range of customs, beliefs, social forms, and material traits of a religious, social, or racial group.

Culvert: A transverse drain used to conduct water under roadways.

Curb Cut: A break or opening onto a road from private property.

Curve length (L): The length of a curve on a road between the Point of Curve and Point of Tangency.

Cut and Fill: A plan to remove (cut) excess soil or add (fill) soil to low spots.

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D

Data Collector: A portable computer usually sized to hold in one hand that automatically records observations made with a total station.

Datum: A reference point for starting a survey.

Deciduous: A type of tree, shrub, or vine that drops all of its leaves in winter.

Dead load: Unchanging or dead weights a structure must support (i.e., roof, beams, flooring).

Deflection: Description of the stiffness of a beam by its tendency to bend under a load.

Deformation: Change of shape as a result of forces being applied to an object.

Deed restrictions: Limitations placed on the owner of property for its usage.

Degree of curve (D): The angle within the Delta angle of a curve that has a chord of 100 feet along the curve. Provides information on how tight the curve will be.

Delta Angle (?): The inclusive angle of a curve Measured from PC to PT.

Design: To plan, create, or devise; may refer to the results of the planning, creating, and devising.

Design brief: Summary of a design project that includes brief descriptions of the following: initial problem, identification of needs to solve the problem, factors/constraints to be considered.

Design elements: Parts that make up an end-product that satisfies a set criteria or constraints.

Design Temperature Differential: The difference between the indoor temperature in winter and the outdoor design temperature in winter. The design temperature differential or design range is used in calculating the space heating requirements of a dwelling unit under the engineering-based methodology.

Detail drawing: Enlargements of specific areas of a structure that are typically drawn where several components intersect or where small members are required.

Determinant beam: A beam with three support reaction forces that can be determined by applying the three equilibrium equations. If a beam has more than three support reactions, it is said to be indeterminate.

Developer: Any property owner, or any person or group with written authorization from the property owner, who intends to improve or to construct improvements upon a given property.

Development: A piece of property of land that has been changed by the addition of improvements.

Diazo reproduction: Diazo prints, also known as blue-line prints, are made by passing an ultraviolet light through a translucent original drawing to expose a chemically coated paper or print material underneath.

Dimensions: Distances between points that delineate relationships between design elements.

Diatomaceous earth: Soft earth formed from the shells of diatoms.

Dispersement: Separation of a quantity.

Displays of Work: Public exhibits of work to allow others to learn about a project and to receive peer evaluation.

Distribution main: The primary trunk line used for distributing water, gas, or electricity within a specific area or region.

Distribution panel: A section or division of a wall where the conductor from the meter base is connected to individual circuit breakers, which are connected to separate circuits for distribution to various locations throughout the structure.

Drain: A pipe or channel by which liquid is drawn off.

Drainage: A system or plan to remove water from a site.

Drip edge: Molding at the edge of a roof designed for effective water shedding and for directing water away from the exterior facing material.

Driveway: A private road providing access from a public way to a building.

Ductile iron: A heavy metal pipe typically used to convey potable water supplies.

Ductwork capacity: The cubic feet per minute of airflow (abbreviated CFM) the ductwork is capable of handling.

Dutch hip: A type of roof shape that combines features of a gable and a hip roof.

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E

Easement: Right of way across someone's land; typically utility lines are placed in easements.

Eave: The lower part of the roof that projects from the wall (also see cornice).

Ecology: Study of the relationships between living organisms and their surroundings.

Economics: The production, consumption, and distribution of goods and services.

Electronic Distance Measuring (EDM): A means or method of measurement that uses electronics at a distance.

Effluent: The discharge of water or wastewater from a treatment process or processes.

Egress: Exits or a way out of.

Electric Meter: A Kilowatt hour measuring device provided by the power company used for billing purposes.

Electrical plan: The display of all of the circuits and systems to be used by the electrical contractor during installation.

Electrical systems: The means of supply, transmission, and distribution of power to a site.

Elements of art: The basic principles of art, such as design, color, symmetry, or proportion.

Elevation: A point's height above an adopted datum, such as mean sea level (MSL).

Elevations: Orthographic drawings that show one side of a building's interior or exterior.

End Vertical Curve (EVC): Point where the vertical curve ends and the road has an even slope again.

Energy: The ability to do work; types include heat, light, sound, chemical, nuclear, mechanical, electrical.

Energy Codes: A set of rules that are intended to regulate the design and construction of an energy system.

Energy resources: The supply that provides energy that is converted into usable power; source types include solar, wind, nuclear, geothermal, fossil fuels, and hydroelectric.

Energy Systems: A means of delivering a structure's power enabling it to do work; it can be by onsite conduction, convection, radiation, or offsite mechanical means.

Engineered beam: A long, thick piece of wood created from smaller wood pieces improving upon the normal capabilities of construction lumber. These products are composed of wood particles (veneer, wood chips, oriented strands, wafers, laminated dimensional lumber, and combinations thereof) bonded by long-lasting adhesives to ensure the structural integrity.

Engineering-Based Methodology: One of two suggested systems that can be used to establish utility allowances. (See also consumption-based methodology.) This method is based on engineering calculations and other technical information that is used to estimate the amount of energy or water a household should reasonably require.

Engineering surveying: A measurement to show size, boundaries, utilities, and topography of a site.

Environment: External surroundings.

Environmental Engineer: A sub-discipline of civil engineering that deals with the treatment of chemical, biological, and/or thermal waste, the purification of water and air, and the remediation of contaminated sites, due to prior waste disposal or accidental contamination. Environmental engineers are also involved in pollution reduction, green engineering, and industrial ecology. Environmental engineering is the modern term for Sanitary engineering. Some other terms in use are public health engineering and environmental health engineering.

Environmentally Friendly: Designing and constructing buildings from renewable materials such as wood from managed forests, earthen materials, and recycled products.

Ethical: Being in accordance with the accepted principles of right and wrong that govern the conduct of a profession.

Equilibrium: State of balance achieved when the forces acting on a structural member are equal to zero.

Evergreen: Plants having foliage that remains green all year.

Exterior: Outside the boundaries of the floor plan.

Eye-contact: Direct visual contact with another's eyes.

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F

Facilities: A structure, equipment, or service that is designed to meet a need; i.e. restroom.

Fascia: A horizontal board nailed to the end of rafters or trusses to conceal their ends.

Feeder: Local streets, Cul-de-sacs, or loops that service neighborhoods.

Fiber bending stress: The measurement of structural members used to determine their stiffness. Represented by (Fb).

Fine adjusting screw: A mechanism that when tightened or loosened makes fine adjustments of surveying equipment in the vertical or horizontal plane.

Finish floor: A floor that has been prepared with a smooth finish suitable for use that may or may not have a sealant applied.

Finishes: Final treatments that are applied to a design or construction element.

Fittings: A general term that usually refers to various piping parts such as tees, valves, fixtures, or elbows.

Fixed beam: A beam with both supports fixed, allowing no rotation at the restrained ends.

Fixed support: A support that totally restrains the beam, sometimes called a fixed end.

Fixtures: Plumbing, electrical, or other trade areas for personal finish devices that are fastened to the structure and become part of the property, such as, toilets, chandeliers, water faucets, doorbells.

Floating foundation: A system and slab formed in one fabrication.

Floor: The inside bottom surface of a room; sometimes refers to a story in a building.

Floor joist: A horizontal structural member used in repetitive patterns to support floor loads.

Floor Plan: A sectional drawing to show a floor from a point four feet above the finished floor level.

Floor plan symbols: Representations used in floor plans to describe items that are associated with living in the home, such as doors, windows, cabinets and plumbing fixtures.

Flow Rate: The rate at which water or wastewater moves through a treatment system or pipe network.

Foam core board: Model building material; a thin piece of foam sandwiched between two pieces of posterboard.

Foliage: Plant leaves, especially tree leaves, considered as a group.

Footings: Lowest member of a foundation system used to spread the loads of a structure across supporting soil.

Force: A push or a pull on an object.

Form: A principle of design that is described by lines and geometric shapes. For best results, the form of a structure should be dictated by its function.

Foresight (FS): The station or location to which a horizontal angle (relative to the backsight), vertical difference, and horizontal distance are measured.

Foundation: System that supports and transfers to the ground a building's loads; may include footings, piers, pilings, foundation walls, and slabs.

Freeway: A road with limited access that generally handles between 1,000-1,300 cars per hour per lane.

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G

Gable: A type of roof with two sloping surfaces that intersect at the ridge of the structure.

Gallons per day: A flowrate unit (gpd), which is typically, used for water distribution and wastewater management systems.

Gallons per minute: A flowrate unit (gpm), which is typically, used for water distribution and wastewater management systems.

Gambrel: A type of roof formed with two planes on each side of the ridge. The lower pitch is steeper than the upper portion of the roof.

Geodetic surveying: Mathematical determination of exact locations of geographical points, shapes, and sizes.

Geotechnical Engineering: A profession that analyzes subterranean rock and soil in order to determine load bearing capabilities essential for a safe and secure structure.

Girder: A horizontal support member at the foundation level.

Global Positioning System (GPS): A surveying technology using specialized radio receivers tuned to signals from military navigation satellites to position survey stations.

Grade beam: The designation of the quality of a manufactured piece of wood.

Grading: Act of changing a property's topography for a purpose.

Green space: Land that consists predominantly of unsealed, permeable, 'soft' surfaces, such as soil, grass, shrubs, and trees.

Ground: An electrical connection to the earth by means of a rod.

Groupings: A number of plants placed in an arrangement within a landscape for maximum impact and appeal.

Gussett: A metal or wood plate used to strengthen the intersection of structural members.

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H

Hard water: Drinking water, usually from a groundwater source, that is high in dissolved minerals, most commonly calcium, magnesium, and iron.

Head loss: Energy loss in hydraulic systems.

Header: The upper portion of a door or window frame.

Heat Loss: The rate of heat transfer in British Thermal Units (BTU) per hour from occupied space to the outdoors. Losses occur through walls, ceilings, and floors of a structure, and through cracks around windows and doors. The heat loss depends on the structure size, construction, design, physical condition, amount of insulation in the walls and ceilings, the assumed indoor temperature, and various other factors.

Heating Degree Days: A measure of the severity of the winter in a given locality: the more heating degree days, the colder the winters. Heating degree days (HDD) are the difference between 65 degrees F and the daily mean (average) temperature when the latter is less than 65 degrees F.

Heckling: To try to embarrass and annoy (someone speaking or performing in public) by questions, gibes, or objections; badger.

Height of Instrument (HI): The vertical distance from the station mark to the center of the trunnion axis of the total station or level.

Hip: The exterior edge formed by two sloping roof surfaces.

Holding Pond: A fabricated containment area for holding storm run-off.

Horizontal Alignment: Tangency established between straight-a-ways and curves on roads.

Horizontal orientation: A view of an object that shows its width.

Horizontal shear: One of three major forces acting on a beam; it is the tendency of the fibers of a beam to slide past each other in a horizontal direction. Represented by (Fv).

Hydraulic detention time: The average amount of time a particle of water stays within a treatment vessel. The hydraulic detention time can be calculated by dividing the vessel volume by the flowrate.

Hydrogeologist: Scientists who study groundwater occurrence and movement.

Hydrographic: Relating to features of a body of water or the study of the flow of water.

Hydrology: The study of the properties and characteristics of earth's water.

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I

Impact loads: Dynamic forces applied by live loads; because they are considered related to live loads, they are generally taken as a fraction of the live loads causing them.

Indeterminant beam: A beam with more than three support reaction forces. The three equilibrium equations are not sufficient to solve for all of the reactions. If a beam has three support reactions, it is said to be determinate.

Indigenous: Originating and growing or living in an area or environment.

Influent: Water or wastewater, partially or completely treated, or in its natural state that flows into a reservoir, tank, treatment component or disposal component.

Infrastructure: Basic installations, such as roads, railways, or factories that determine the economic power of a country, city, or town.

Ingress: Entrances or a means to enter.

Inlet: A narrow passage for water to enter a system.

Interior: Within the boundaries of the floor plan.

Interviews: A verbal process to inform and provide suggestions for improvement.

Introduction: Something spoken, written, or otherwise presented at the beginning of a presentation or written piece; used in presenting a person.

Irrigation: A process to supply something, such as dry land with water by means of ditches, pipes, or streams; to water artificially.

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J

Jack stud: A wall member that is cut shorter than other studs to allow for an opening, such as a window (also called a cripple stud).

Jamb: The vertical member of a door or window frame.

Journal: Daily record or collection of writings, sketches, and research that express the design process.

Junction box: A metal or plastic container that protects electrical wiring splices in conductors or joints in a run.

Juried presentation: A showing or viewing of something that has been assessed by a group of judges or evaluators.

Jury: A panel of individuals that assess a design project with a formal presentation.

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K

Kaolin: A fine, white clay used in ceramics and refectories and as a filler or coating for paper and textiles. This clay is formed by the weathering of pegmatities or mica schists from the acids in ground water.

King stud: A full-length piece of wood placed at the end of a header.

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L

Land: A solid part of the earth's surface, ground, or soil.

Land surveying: The process of measuring and locating physical entities on a plot of land to obtain a legal description.

Landscape design: The aesthetic improvement of land with the use of existing resources and the addition of plant material as needed.

Landscape horticulturist: A person whose profession is the cultivation of fruits, vegetables, flowers, or ornamental plants for decorative and functional alteration and planting of grounds.

Landscaping: The improvement of a plot with the responsible use of existing and new plant material.

Lateral: Of, relating to, or situated at or on the side.

Lateral loads: Sideways directed loads sustained by a structure that may be caused by winds or seismic activity.

Layout: Arrangement of design components to satisfy the design requirements.

Least squares: A method of determining the curve that best describes the relationship between expected and observed sets of data by minimizing the sums of the squares of deviation between observed and expected values. It is a process used to determine the best fit of a line or curve (depending on whether a person is using linear, non linear, damped, etc.) to a matrix of data points used in prediction.

Legal description: A written passage or statement that describes property; may be one of three types: metes and bounds, rectangular survey system, and lot and block.

Lending institution: Organization that is in the business of providing monetary funds for individuals or companies needing funds.

Leveling base: A foundation or area designed to level surveying instruments prior to use; four leveling screws are used.

Leveling Rod or Target rod: A device with a graduated scale in 1/10ths or 1/100ths of feet that is focused on through the telescope.

Liquid Limit: Minimum moisture content at which the soil will flow upon application of a sheering force.

Line: A sense of direction or movement in the design of a structure which helps to relate it to the site and the natural surroundings.

Line-of-sight: An imaginary line from the eye to a perceived object.

Live load: Changing (live) weights on a structure in need of support, such as people, furniture, rain, or snow.

Load: Weight a structure must support.

Load paths: The direction a force will follow along structural members to reach its foundation and ultimately the ground supporting the foundation.

Long span: A one-story structure with a span greater than 12 to 15 m and large free spaces between columns.

Lot size: The number of square footage in a plot of land that is under consideration for development.

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M

Main: The public pipe or wire that conveys a utility from one point to another.

Maintenance: The work of keeping something in proper condition; upkeep.

Management: People in charge of carrying out the administration of business.

Manhole: An entry through which a person may gain access to an underground or enclosed structure.

Mansard: A four-sided, steep-sloped roof.

Materials: The products that are used to protect the exterior of the building from weather, such as roofing, wall coverings, doors, and windows.

Mat (Raft) foundations: A foundation used when soil bearing is relatively low or where loads are heavy in relation to soil-bearing capacities. This foundation type is essentially one large footing under an entire building, which distributes the load over the entire mat. A mat is called a raft foundation when it is placed deep enough in the soil that the soil removed during excavation equals most or all of the building's weight.

Meridians: Lines of longitude used in legal property descriptions.

Meter: An instrument used to measure electrical quantities.

Metes: Measurements used to identify the boundaries of a property.

Micaceous: A mineral that crystallizes in thin, flexible layers resistant to heat.

Minute: A measurement of 1/60th of a degree, where 360 degrees equals a circle.

Models: A model, or mock-up, is a three-dimensional representation of an architectural design solution that is used to help communicate design concepts. The model can either be a physical model or a computer-generated model of the design.

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Modulus of elasticity: The degree of stiffness of a beam. Represented by (e).

Moment: Tendency to rotate about a point determined by the product of a force multiplied by the distance from this force to this point.

Monument: A known reference point on an immovable object used to reference topographical data usually identified by a brass circle with data inscribed on it.

Multi-Family: Distinction given in building codes to a structure where more than one family unit would reside.

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N

NAD 27: The North American Datum of 1927 is a horizontal reference datum.

NAD 83: The North American Datum of 1983 is a horizontal reference datum, which superseded NAD 27.

National Geodetic Survey (NGS): A federal government activity that is responsible for national programs in geodesy and geodetic surveying. NGS is a division under the National Ocean Service of the National Oceanic and Atmospheric Administration (NOAA) within the Department of Commerce.

Native plants: Plants, which are indigenous to a particular area.

NAVD 88: The North American Vertical Datum of 1988 is a vertical reference datum, which superseded NGVD 1929.

NGVD 29: The National Geodetic Vertical Datum of 1929 is a vertical reference datum.

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O

Outlet: An electrical receptacle which allows current to be drawn from a system.

Overhang: The horizontal measurement of the distance the roof projects from a wall.

Overhang beam: A beam supported with two supports, one or both supports are not located at the end of the beam.

Overview: A broad, comprehensive view; a summary or review.

Ownership: Having legal authority over something; i.e. land or buildings.

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P

P & Z Board: Local planning and zoning committee that is comprised of community individuals who make decisions governing the development of property within the community.

Panel box: The electrical enclosure where the service is connected to the individual circuits in the structure.

Parallels: Lines of latitude used as a reference point in legal descriptions of property.

Particle board: A formed panel consisting of particles of wood flakes, chips, and shavings and bonded together with synthetic resin glue. Used for countertop or veneer panel underlayment.

Peer evaluation: Process of checking another's work against the requirements that have been given and giving constructive feedback.

Peer Review: A method that enables reflection and revision of work completed.

Perspective Drawings: A type of pictorial drawing that provides the illusion of depth by converging all horizontal lines which represent the object's depth to a single vanishing point on the horizon (for one-point perspectives) or to two vanishing points on the horizon (for a two-point perspective). Additional Information: In architectural drawing, one-point perspectives are most commonly used for drawing room interiors; two-point perspectives are used most often to illustrate the exterior of a structure: and three-point perspectives are used for exterior illustrations that also require the illusion of height, such as in a tall building.

pH: Measure of acidity.

Photogrammetry: The science of obtaining reliable information about physical objects through the use of recording, measuring, and interpreting photographic images.

Pier: Any of various vertical supporting structures, such as a pillar, supporting an arch or roof or buttress.

Pile foundations: Deep foundations acting like large nails that are hammered into the soil wit/;h pile drivers to deliver the structure load into a greater mass of soil, or to deliver the loads to a stiffer soil or bedrock stratum.

Pile: A heavy beam of timber, concrete, or steel, driven into the earth as a foundation or support for a structure.

Piling: A structure composed of piles.

Pin support: Type of structural member connection usually metal.

Pitch: Slope (comparison of rise over run) of a roof.

Plagiarize: Act of using another author's work without giving proper credit; literary theft.

Plan: Top view in an engineering drawing.

Plastic Limit: The lowest moisture content at which a soil can be rolled into a thread 1/8 inch in diameter. Sands are non plastic and cannot be rolled.

Plat: A map of part of a city or township showing some specific area, such as a subdivision made up of several individual lots.

Platy: A flat particle having one dimension relatively small in relation to the other two.

Plot: A small piece of ground; a measured area of land; a lot.

Plot Plan: Layout of a parcel of land.

Point of Beginning (POB): The first point in an engineering project referenced to a bench mark, such as 0+00.

Point of Curve (P.C.): The Station Point where a curve begins.

Point of Intersection (P.I.): The Station Point where two road grades or transit lines intersect.

Point of Reference (POR): A location of known or assumed elevation and/or horizontal coordinates.

Point of Reverse Curve (PRC): The Station Point where two curves meet and change direction.

Point of Tangency (PT): The Station Point where a curve ends and a Straight-a-way begins.

Polyvinyl Chloride (PVC) Pipe: Pipe that is constructed with a polymer formed by polymerization of vinyl chloride monomer, sometimes called vinyl. The white PVC pipe is often found in structures and used for gravity pipe systems such as wastewater drains. Green PVC pipe is used for gravity sanitary sewers.

Poorly Graded: Soil classification where there is only one size, uniformly graded, or a soil that contains only a few differently sized particles, gap graded.

Portfolio: A written record of the development of a project from inception to completion. The three types of portfolios are formative, summative, and marketing.

Position: The coordinates, in a horizontal reference system, which identify a station mark or feature. Latitude and longitude, and Northing and Easting are examples of position coordinates in systems used in surveying.

Potable water: Raw or treated water that is considered safe to drink.

Pounds per Square Inch (PSI): A unit of pressure measurement.

Precast Concrete: Concrete building components which are formed and cured at a factory and then transported to a work site for erection.

Pressurized: Result of pressure being exerted upon something.

Prevailing winds: Direction from which the wind most frequently blows in a given area of the country.

Principles of design: The basic rules or standards that determine a good design, such as form, function, and aesthetics.

Prism: Reflecting device used with a total station or other electronic distance measuring instruments.

Private: Structure or property development that has restricted or limited access for certain groups of people.

Private Force Main: A privately owned utility pipe, conduit, or line that is under pressure.

Private utilities: Any gravity sewer, force main, sewage treatment plant or water or electrical supply system that serves residential subdivisions or other groups of uses or structures and that is not owned and maintained by the public utilities.

Profile: The elevation (or front view) of property showing the vertical information created if a vertical slice is taken through the property.

Project: An undertaking that is usually large and encompasses planning, execution, and presentation to varying degrees as addressed in the scope.

Project notebooks: Notebooks documenting an undertaking that is evidence of design process, research, and final implementation of the design solution.

Property Owners: Legal possessors of land.

Propped beam: A beam with two supports and one end is fixed.

Proportion: A principle of design that deals with the size and shape of areas and their relationship to one another.

Protractor: A measurement device that is graduated in degrees and minutes and that is used for measuring horizontal angles.

Public: Structure or property development that is intended for the use of all people.

Publicly Owned Treatment Works (POTW): Municipal owned water treatment or wastewater treatment facility.

Public Sanitary Sewer System: Community owned wastewater system.

Public Water System: Community owned potable water distribution system.

Pump stations: Pumps, typically housed in buildings, which add energy to water distribution and sanitary sewer systems.

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R

Radius (R): The perpendicular distance between the Transit line and the center of the curve, measured from the Point of Curve.

Rafter: The inclined structural member of a roof system designed to support roof loads.

Realtor: A person whose business is selling and leasing property; an estate agent.

Regulators: Persons in a position to control the flow or distribution of entities.

Regulations: Rules or ordinances that must be followed in the design of a structure or property development.

Reinforcement bars (rebar): Rods that are used for compressive strength; that is, the bar absorbs the push force.

Reinforcing rods: Rods that are used for tensile strength; that is, the rod absorbs the pull force.

Relief: The elevations or inequalities of a land surface giving it three dimensional qualities.

Renderings: Pictorial drawings that illustrate a design's details.

Residential Structure: Any structure used for living purposes.

Resources: Things needed to get a job done. The basic technological resources are tools and machines, materials, information, energy, capital, time, and people.

Restrictions: Constraints that limit what can be done.

Rhythm: A principle of design that describes the illusion of flow or movement created by having a regularly repeated pattern of lines, planes, or surface treatments.

Ridge: The uppermost area of two intersecting roof planes.

Ridge board: A horizontal member that rafters are aligned against to resist their downward force.

Right-of-Way (ROW): The strip or area of land around a state highway granted easement or fee paid to a local, state, or federal government agency.

Rise: The amount of vertical distance between one tread and another.

Riser: A water supply pipe that extends vertically one story or more to carry water to fixtures.

Roller support: Joint connection that allows for movement of a structural member.

Roof system: Primary system located on the top of a structure that protects its interior from the natural elements.

Rough Opening: The unfinished opening between framing members allowed for doors, windows, or other assemblies.

Run: The horizontal distance of a set of steps or the measurement describing the depth of one step.

R-value: Measurement of thermal resistance used to indicate the effectiveness of insulation.

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S

Scale: 1. A measuring device used to draw a proportionately reduced representation of a design. 2. A mineral deposit left by hard water.

Schedule Key: Sets of letters and numbers enclosed in geometric shapes that are used to cross reference a feature on a drawing to its corresponding part on a schedule, often referred to as a tag.

Schedules: Written lists of similar components and their specifications, such as windows and doors.

Scissor truss: A roof truss design characterized by two crossing diagonal bottom chords that are frequently used when a vaulted ceiling is desired.

Seasonal wind pattern: A design of natural origin of how the wind flows during different seasons of the year.

Section Detail: A vertical cut through the road to show construction details.

Section Modulus: The moment of inertia divided by the distance from the neutral axis to the extreme fiber of the cross section. If a member is rectangular then S = bd² / 6 (in3) is used in bending calculations, where b= width and d= depth. Does not work for I- shape.

Sections: Views that are formed by slicing a structure or part of a structure along a cutting plane line to show interior details.

Seismic load: Earthquake related forces that must be accounted for in the structural design; specified in the building codes.

Self-assessment: An assessment technique used to enhance learning and understanding through self-evaluation.

Septage: The biodegradable waste from septic tanks and similar treatment systems. Septage includes the sediments, water, grease, and scum pumped from a septic tank.

Septic: An anaerobic condition of water and wastewater.

Septic System: A method to handle raw sewage on site; consists of piping from the structure to the tank, a tank to hold sewage where bacteria breaks it down, and a drain field where liquid is dispersed.

Service: A facility providing the public with the use of something, such as water or transportation.

Service entrance: An entry to a structure or property that is used for delivery of goods and removal of refuse; usually located at the rear.

Service line: A pipe or conduit conveying a utility from a distribution main to the meter or entry point of any individual property.

Setback: The minimum legal distance from a property line or street where improvements to a site can be built or the minimum distance from the property lines to the front, rear, and sides of a structure.

Settling: To cause to sink, become compact, or come to rest; to cause (a liquid) to become clear by forming a sediment; to stabilize.

Shear: Stress that occurs when two forces from opposite directions are acting on the same member; tends to cut a member just as scissors cut paper.

Sheathing: A covering material placed over walls, floors, and roofs that serves as a backing for finishing materials.

Shed: A small structure, either freestanding or attached to a large structure used for storage or shelter.

Shock waves: Compressed waves that travel from an earthquake's hypocenter at different velocities impacting structures on the earth's surface; intensity varies according to the type of soil the wave is traveling through.

Sight Distance: The farthest point a driver can see around obstacles.

Sill: A horizontal wood member placed at the bottom of walls and opening in walls.

Silt: Sedimentary material less than .05mm in size.

Simple beam: A beam with a uniform load evenly distributed over its entire length and supported at each end.

Single Family: Distinction given in building codes to a stand alone structure where only one family unit would reside.

Single-phase: Producing, carrying, or powered by a single alternating voltage.

Site: An area of land generally one plot or construction lot in size. The term site is synonymous with plot and lot.

Site Location: Physical placement of a property and its surrounding vicinity.

Site Orientation: The placement of a structure on a property with certain environmental and physical factors taken into consideration.

Site plan: A map of a piece of land that may be used for any number of purposes. It shows the relationship between a structure and its physical surroundings. Also known as a plot or lot plan.

Sizing: Process of choosing the correct structural member necessary to carry specific loads in a design.

Shrubs: Woody plant smaller than a tree with several stems rising from the same root.

Slope: The relationship of the rise to the run expressed as a proportion or a percent, for example 1/10 or 10%.

Sketches: A collection of freehand drawings that communicate an idea; three types: program, design, and thumbnail.

Sketching: An effective means of communication that utilizes freehand drawing.

Soffit: A lowered ceiling, typically found in kitchens, halls, and bathrooms to allow for recessed lighting or HVAC ducts.

Soil Perc Test: A method to determine the permeability of the soil.

Soil pH: The measure of acidity of the soil.

Soil stack: Any vertical pipe in a waste water system.

Solar Orientation: A way of indicating the exposure to the sun. Solar orientation provides for excellent exposure to the sun. Solar access refers to the availability of direct sunlight to a structure or construction site.

Sound Orientation: A way of indicating the exposure to sound. Sound orientation includes determining the sounds that the client will contend with and what other design components may be used to soften the sound impact, such as droning road noise.

Space allocation: The allocation of square footage based on the functional needs within an area.

Space planning: The process of listing functions to be performed within a design and developing relationships as to their placement taking into consideration the design criteria.

Span: Horizontal distance between two supporting members.

Spatial relationship: The proportion of space and objects and how they relate to one another.

Specification Manuals: Reference materials specific in nature which provide additional information that is not given in the working drawings.

Spread foundation: Foundation where the structural load is spread out over a broad area under a building utilizing horizontal rebar mats to anchor the building as a whole or to anchor individual columns or sections separately. Spread foundation is sometimes called "footing foundations" or "spread footing" and is a frequent type of foundation utilized in low rise buildings.

Stable: The condition of a structural member that has been designed to handle the loads it will carry to prevent failure.

Static Head Pressure: The water pressure within a pipe when the water is not moving.

Statics: Branch of mechanics dealing with the forces that produce a state of equilibrium.

Station: A location sometimes called a Station Point, at the intersection of two Traverse lines. Stations are usually sectioned into 100 foot intervals with the hundreds separated from the tens and ones by a + sign. E.g. 3+27 would be 327 feet from the Point of Beginning.

Storm Drain: A drain designed to collect surface water runoff.

Stormwater Retention Areas: Manmade areas for the collection of storm water.

Strain: To alter the relations between the parts of a structure or shape by applying an external force; deform.

Stress: Live or dead load acting on a structural member that results as the material resists the external force; internal force per unit area of the member's cross section.

Structural Engineer: A profession that studies and understands the basic principles that define and characterize the behavior of physical objects subjected to forces and the designs of such things as bridges, buildings, dams, and stadiums.

Structure: Something made up of interdependent parts in a definite pattern of organization; an interrelation of parts as determined by the general character of the whole.

Subfloor: The flooring surface that is laid on the floor joint and that serves as a base layer for the finished floor.

Subsurface: Soil conditions below ground.

Summary: A statement or presentation of the main points in a condensed form; concise.

Supply: Input line into an area of a structure.

Swale: A man made depression or low lying land feature used for drainage (i.e., a ditch).

Symmetry: (1) Exact correspondence of form and constituent configuration on opposite sides of a dividing line or plane or about a center or an axis. (2) Beauty as a result of balance or harmonious arrangement.

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T

Tangent Line: A single contact point or along a line; touching but not intersecting.

Telescope: An instrument that contains the lens focusing adjustment and cross hairs for sighting.

Telescope level: A spirit (air bubble in fluid encased in a glass cylinder) level used for leveling the instrument.

Tension: Forces that cause a material to stretch or pull apart.

Terrain: The characteristic of land on which the proposed structure will be placed.

Test boring: The process of removing a small diameter core of soil and earth to determine the subterranean features and composition.

Texture: A principle of design which refers to the roughness or smoothness, including reflective properties, of a material or object and its related physical and visual effects.

Three phase: Electrical supply utilizing 4 wires with three lines, each 120° out of phase with the others. Used for commercial or industrial utility; well suited to run heavy motors.

Timeline: Sequential listing of information according to the dates it took place or should take place.

Top plate: The upper horizontal framing member used in residential wall construction, frequently being doubled to provide for stiffness and for support of joists or trusses above.

Topography: The configuration of a surface including its relief and the position of its natural and cultural features.

Total dynamic head (TDH): The pressure within a pipe system with the water in motion. TDH = Static head minus head loss.

Total Station: An electronic surveying instrument that combines angles and distance-measuring capabilities in a single unit.

Traffic flow: The route that people follow as they move from one area to another.

Transit Line: The path or center line of a road.

Transmission Main: The main trunk of a utility system.

Transportation Engineering: A profession that designs and analyzes transportation systems, such as highway construction, railways, airports, urban and suburban road networks, parking areas, and traffic control systems.

Trap: A device for sealing a passage against the escape of gases, especially a U-shaped or S-shaped bend in a drainpipe that prevents the return flow of sewer gas by means of a water barrier.

Traverse: A series of lines of known length connected by known angles.

Tree canopy: The outer limits of a tree's foliage shown from directly overhead.

Tributary width: The accumulation of loads that are directed to a structural member; always half the distance between the beam to be designed and the next bearing point.

Trimmer: Joists or rafters that are used to frame an opening in a floor, ceiling, or roof.

Tripod: A three-legged stand that provides a stable mounting base for a surveying instrument.

Truss: A rigid framework, to support a roof or bridge; made from shorter components connected in triangles with pin connections.

Turning Points: The stations used when surveying. Also called Traverse Stations or Station Points.

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U

Ultraviolet Disinfection: A final treatment method in which partially treated effluent is exposed to ultraviolet light to kill pathogens and microorganisms.

Underground: Any utility located below the ground level.

Unity: A principle of design related to the commonality of the design or decorating pattern that ties a structure together.

Universal accessibility: A design to provide access with the mobility limited person in mind; Americans with Disabilities Act (ADA) 1997 and the International Code Council have specified guidelines that are to be followed.

USCS: Unified Soil Classification System.

USDA hardiness map: A map of the United States that shows the range of temperatures in zones for vegetation growth; used when identifying plant material to be used in landscaping.

Utilities: Any service provided by an offsite supplier.

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V

Valley: The internal corner formed between two intersecting roof structures.

Vellum (tracing paper): Drafting paper that is specially designed to accept pencil or ink.

Vent stack: Any vertical pipe in a waste water system whose purpose is to provide a pathway for built up gasses.

Vertical alignment: Tangency between a vertical curve and a road with an even slope.

Vertical Curve (VC): The transition created when a road travels over a hilltop or down a valley and up again.

Vertical orientation: A view of an object that shows its height.

Vertical shear: A stress acting on a beam, that causes a beam to drop between its supports.

Viable: Capable of success or continuing effectiveness; practicable.

Viability analysis: Evaluation process that takes into account the factors that will influence and determine the successful implementation of a proposed project.

Vibrations: Quick forward and backward motions.

View Orientation: A visualization of mountains, city lights, water, or even a developed site, such as a golf course; is optimized in the site orientation.

Volt: The unit used in measuring electrical pressure.

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W

Wall Section: A partial section that shows only typical roof, wall, floor and foundation information for one typical wall rather than the full structure.

Waste Treatment Engineering: The profession that is responsible for designing and analyzing waste water treatment facilities, such as sanitary waste, disposable waste, and water treatment facilities.

Wastewater: The spent or used water from an individual household, a community, or commercial establishment, which contains dissolved and suspended matter that is harmful to human health and the environment. Wastewater requires treatment to remove bacteria and pathogens, either through an onsite decentralized wastewater treatment system or a centralized municipal sewage system, before it can safely be released into the environment. Household wastewater includes liquid-solid mixtures from toilets, sinks, showers, bathtubs, washing machines, dishwashers, and other drains.

Water Management Engineering: A profession that studies the use of hydraulic and hydrologic principles to design drainage systems, detention and retention ponds, navigational waterways, dams, and lakes.

Watt: A unit of electrical power, which is composed of both voltage and amperage.

Weatherhead: Special fitting used to attach an electrical service line to a building or structure.

Webs: Interior members of the truss that span between the top and bottom chord.

Well-Graded: Soil classification where there are a variety of particle sizes present.

Wetlands: Environmentally sensitive lands that have a large concentration of water on it that filters surface water back into the aquifer; usually have developmental restrictions placed upon their usage.

Wind break: A hedge, fence, or row of trees serving to lessen or break the force of the wind.

Wind load: A wind load is dynamic in nature because wind pressure, direction, and duration of wind are constantly changing. To accommodate this with wind load, a standard is used. Wind loads are treated as lateral loading on walls and in a downward pressure or uplift forces on roof planes.

Wind Orientation: Involves determining prevailing winds, which should be taken into account in the placement of a home or business.

Working drawings: The set of plans from which a structure will be built. Working drawings are the vehicle by which the designer graphically conveys the final design solution. Their size is dependent upon the scope and nature of the project.

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Z

Zenith Angle: The angle, measured in the vertical plane, between straight up (zero) and the target of observation. The horizontal, therefore, is 90 degrees.

Zoning: Clarifications for property development that govern the design and use of buildings, structures, and utilities within a municipality.

2D: A graphic representation that shows only two of an object's dimensions at one time, such as height and width, or width and depth, or height and depth.

3D: A graphic representation that shows all three dimensions of an object at one time: height, width, and depth.

3D modeling (computer): A computer-based modeling system that allows the designer to create model geometry on an x-, y-, and z-axis system.

A-frame: A structure, such as a house, with steeply angled sides that meet at the top in the shape of the letter A.

Above ground: Term applied to any utility that is brought into a property situated or taking place on or above the surface of the ground.

Absorption: The process whereby one substance is physically taken into and included within another substance, as the absorption of water by soil.

Adjacency matrix: A matrix used to clarify the design parameters for the client by rating components of a project based on most desirable features and placement.

Angle of Repose: The angle, measured from the horizontal, that granular material is stable while unsupported.

Architecture: The profession of designing buildings and environments with consideration for their aesthetic effect.

Architectural styles: The design element of a structure that is identified by the distinguishing characteristics of the exterior.

Arterial: Roads that carry between 400 to 800 cars per lane per hour depending on businesses, parking, signs, and control signals.

Aquifer: An underground geological formation or group of formations containing usable amounts of groundwater that can supply wells and springs.

Artifact: An object produced or shaped by human craft, especially a tool, weapon, or ornament of archeological or historical interest.

Attorney: A person legally appointed by another to act as his or her agent in the transaction of business, specifically one qualified and licensed to act for plaintiffs and defendants in legal proceedings.

Backsight (BS): The reference point from which horizontal angles, vertical and horizontal differences are measured.

Baffle: A shield usually made of scrap material to keep insulation from plugging eave vents; also used to describe wind- or sound-deadening devices.

Balance: A principle of design dealing with the relationship between the various areas of a structure as they relate to an imaginary centerline; sometimes referred to as symmetrical or equally proportioned.

Bearing points: A property boundary location identified by the distance from a fixed point and at an angle and direction relative to that point.

Bearings: would indicate a direction that is 56-degrees, 45-minutes from the south to the west. Directions with reference to one quadrant of a compass used to identify property boundaries in the metes and bounds system. Example: (S 56° 45' W)

Begin Vertical Curve (BVC): On an engineering drawing, the point at which the road transitions from an even slope to a vertical curve.

Benchmark: A known reference point or location of known or assumed elevation and/or horizontal coordinates.

Bending: One of three major forces acting on a beam. It is the tendency of a beam to bend or sag between its supports.

Bentonite: 1. A very fine grained clay formed from decayed glass particles in volcanic rock which forms a watertight bond when compacted. One form of it, Sodium Bentonite, absorbs water and swells to about 20 times its original size. The other, Calcium Bentonite, does not change size. Bentonites are generally used to seal dump sites, pond bottoms and other areas used to contain water or chemicals. 2. An absorbent aluminum silicate clay formed from volcanic ash and used in various adhesives, cements, and ceramic fillers.

Bird's mouth: A notch cut into a rafter to provide a bearing surface where the rafter intersects the top plate.

Blocking: Framing members, typically wood, placed between joist, rafters, or studs to provide rigidity (also called bridging).

Blueprints: A generally accepted term for a set of printed drawings created by the Diazo reproduction process. Original blueprints were created by a wet chemical process that caused the background to be blue and any lines or printing to be white.

Body Language: The gestures, postures, and facial expressions by which a person manifests various physical, mental, or emotional states and communicates nonverbally with others.

Boxes: A metal or plastic container equipped with clamps, used to terminate a conduit. Also known as an outlet box.

Bounds: A limit, "boundary" as used in the Metes and Bounds system for the legal description of property.

Bubble diagrams: Freehand sketches used to determine room locations, flow of traffic, and spatial relationships. They are the first step in the design process used to represent spatial relationships and placement of circulation flow.

Building Codes: Legal requirements designed to protect the public by providing guidelines for structural, electrical, plumbing, and mechanical areas of a structure.

Building Inspectors: Individuals who inspect new construction to make sure that the methods and materials meet local and national code requirements.

Building section: A type of drawing showing an object as if it had been cut through from the peak of the roof to the base of the foundation in order to show interior construction.

Building Structure: The arrangement of parts to form a whole. A building structure's primary function is to support and redirect loads and forces safely to the ground. It constantly withstands forces of wind, effects of gravity, vibrations, and sometimes earthquakes.

Cantilever beam: A long piece of wood or metal used to support a structure; a horizontal beam that is fastened only at one end and extends beyond a supporting surface.

Catchbasin: A device used to capture sediment, nutrients, metals, and hydrocarbons suspended in runoff from impervious surfaces before being conveyed to a storm sewer network or to another water-quality treatment system.

Ceiling joist: The horizontal member of the roof which is used to resist the outward spread of the raters and to provide a surface on which to mount the finished ceiling.

Chipboard: A flat construction material, made by using flat chips of wood bonded with formaldehyde glue; sometimes referred to as wafer board; term used in the construction industry for Oriented Strand Board (OSB). OSB was developed as an inexpensive replacement for plywood. It comes in several thicknesses only some of which are rated for sheathing or decks.

Circuit: The various conductors, connections, and devices found in the path of electrical flow from the source through the components and back to the source.

Circuit Breaker: An electrical safety switch that automatically opens a circuit when excessive amperage occurs.

Civil engineer: A person trained in the design and construction of public works projects, such as highways, bridges, sanitation facilities, and water treatment plants.

Clean-out: A special fitting that allows access to drainage lines for removing obstructions that develops in those lines.

Closed Traverse: A collection of Traverse lines that return to the POB (Point of Beginning) or other Control Point; the boundaries of a property.

Collar: Horizontal ties between rafters near the ridge to help resist the tendency of the rafters to separate.

Color: An integral part of design and decorating which helps distinguish exterior materials and accents shapes.

Columns: Vertical, beam members which are responsible for supporting compressive loads and transferring those loads to the foundation of a structure.

Common practices: Procedures that are widely accepted by a group of people as the preferred way to accomplish certain tasks.

Competitions: Contests used to show or expose work to different forms of evaluation and comparisons to alternate solutions.

Complex beam: Beam with a non-uniform load at any point on it, having supports that are not located at its end.

Construction Management Engineering: A profession that is responsible for managing and providing quality control, reviewing contracts, ordering materials, and hiring and scheduling sub-contractors for a structural engineering job.

Constructive criticism: Comments serving to improve or advance; providing a helpful critical judgment expressed with knowledge.

Consumption-Based Methodology: One of two suggested systems that can be used to establish utility allowances. (See also engineering-based methodology.) This method is based on actual consumption data from utility bills or checked meter readings. Data is used to estimate the amount of energy or water a household should reasonably require.

Continuous foundation: A base on which something rests; poured or fabricated in one complete form, such as a concrete foundation.

Contour: Lines on a map showing the topographical outlines of the physical characteristics of the land or a line that joins points of similar elevation.

Contractor: A person responsible for directing a project or a portion of the work on a project as in the case of a subcontractor; usually a legally binding agreement is signed and a bond posted to ensure completion.

Control: Any station for which position coordinates and/or elevation is already known, and from which the positions or elevations of unknown stations are determined.

Cooling Degree Days: A measure of the severity of the summer in a given locality: the more cooling degree days, the hotter the summers. Cooling degree days (CDD) are the difference between 65 degrees F and the daily mean (average) temperature when the latter is more than 65 degrees F.

Corner post: The built up vertical section of wall framing used to provide stability and nailing surface at the intersection of wall sections.

Critical buckling load: Large compression load that causes a column to become unstable, resulting in a sudden lateral deflection of the column.

Cross bracing: Boards fastened diagonally between structural members, such as floor joists, to provide rigidity.

Data Collector: A portable computer usually sized to hold in one hand that automatically records observations made with a total station.

Degree of curve (D): The angle within the Delta angle of a curve that has a chord of 100 feet along the curve. Provides information on how tight the curve will be.

Design brief: Summary of a design project that includes brief descriptions of the following: initial problem, identification of needs to solve the problem, factors/constraints to be considered.

Design Temperature Differential: The difference between the indoor temperature in winter and the outdoor design temperature in winter. The design temperature differential or design range is used in calculating the space heating requirements of a dwelling unit under the engineering-based methodology.

Detail drawing: Enlargements of specific areas of a structure that are typically drawn where several components intersect or where small members are required.

Determinant beam: A beam with three support reaction forces that can be determined by applying the three equilibrium equations. If a beam has more than three support reactions, it is said to be indeterminate.

Developer: Any property owner, or any person or group with written authorization from the property owner, who intends to improve or to construct improvements upon a given property.

Diazo reproduction: Diazo prints, also known as blue-line prints, are made by passing an ultraviolet light through a translucent original drawing to expose a chemically coated paper or print material underneath.

Displays of Work: Public exhibits of work to allow others to learn about a project and to receive peer evaluation.

Distribution main: The primary trunk line used for distributing water, gas, or electricity within a specific area or region.

Distribution panel: A section or division of a wall where the conductor from the meter base is connected to individual circuit breakers, which are connected to separate circuits for distribution to various locations throughout the structure.

Drip edge: Molding at the edge of a roof designed for effective water shedding and for directing water away from the exterior facing material.

Ductwork capacity: The cubic feet per minute of airflow (abbreviated CFM) the ductwork is capable of handling.

Electronic Distance Measuring (EDM): A means or method of measurement that uses electronics at a distance.

Electric Meter: A Kilowatt hour measuring device provided by the power company used for billing purposes.

Electrical plan: The display of all of the circuits and systems to be used by the electrical contractor during installation.

Energy Codes: A set of rules that are intended to regulate the design and construction of an energy system.

Energy resources: The supply that provides energy that is converted into usable power; source types include solar, wind, nuclear, geothermal, fossil fuels, and hydroelectric.

Energy Systems: A means of delivering a structure's power enabling it to do work; it can be by onsite conduction, convection, radiation, or offsite mechanical means.

Engineered beam: A long, thick piece of wood created from smaller wood pieces improving upon the normal capabilities of construction lumber. These products are composed of wood particles (veneer, wood chips, oriented strands, wafers, laminated dimensional lumber, and combinations thereof) bonded by long-lasting adhesives to ensure the structural integrity.

Engineering-Based Methodology: One of two suggested systems that can be used to establish utility allowances. (See also consumption-based methodology.) This method is based on engineering calculations and other technical information that is used to estimate the amount of energy or water a household should reasonably require.

Environmental Engineer: A sub-discipline of civil engineering that deals with the treatment of chemical, biological, and/or thermal waste, the purification of water and air, and the remediation of contaminated sites, due to prior waste disposal or accidental contamination. Environmental engineers are also involved in pollution reduction, green engineering, and industrial ecology. Environmental engineering is the modern term for Sanitary engineering. Some other terms in use are public health engineering and environmental health engineering.

Environmentally Friendly: Designing and constructing buildings from renewable materials such as wood from managed forests, earthen materials, and recycled products.

Ethical: Being in accordance with the accepted principles of right and wrong that govern the conduct of a profession.

Fiber bending stress: The measurement of structural members used to determine their stiffness. Represented by (Fb).

Fine adjusting screw: A mechanism that when tightened or loosened makes fine adjustments of surveying equipment in the vertical or horizontal plane.

Finish floor: A floor that has been prepared with a smooth finish suitable for use that may or may not have a sealant applied.

Fixtures: Plumbing, electrical, or other trade areas for personal finish devices that are fastened to the structure and become part of the property, such as, toilets, chandeliers, water faucets, doorbells.

Floor plan symbols: Representations used in floor plans to describe items that are associated with living in the home, such as doors, windows, cabinets and plumbing fixtures.

Foam core board: Model building material; a thin piece of foam sandwiched between two pieces of posterboard.

Footings: Lowest member of a foundation system used to spread the loads of a structure across supporting soil.

Form: A principle of design that is described by lines and geometric shapes. For best results, the form of a structure should be dictated by its function.

Foresight (FS): The station or location to which a horizontal angle (relative to the backsight), vertical difference, and horizontal distance are measured.

Foundation: System that supports and transfers to the ground a building's loads; may include footings, piers, pilings, foundation walls, and slabs.

Gallons per day: A flowrate unit (gpd), which is typically, used for water distribution and wastewater management systems.

Gallons per minute: A flowrate unit (gpm), which is typically, used for water distribution and wastewater management systems.

Gambrel: A type of roof formed with two planes on each side of the ridge. The lower pitch is steeper than the upper portion of the roof.

Geodetic surveying: Mathematical determination of exact locations of geographical points, shapes, and sizes.

Geotechnical Engineering: A profession that analyzes subterranean rock and soil in order to determine load bearing capabilities essential for a safe and secure structure.

Global Positioning System (GPS): A surveying technology using specialized radio receivers tuned to signals from military navigation satellites to position survey stations.

Green space: Land that consists predominantly of unsealed, permeable, 'soft' surfaces, such as soil, grass, shrubs, and trees.

Groupings: A number of plants placed in an arrangement within a landscape for maximum impact and appeal.

Hard water: Drinking water, usually from a groundwater source, that is high in dissolved minerals, most commonly calcium, magnesium, and iron.

Heat Loss: The rate of heat transfer in British Thermal Units (BTU) per hour from occupied space to the outdoors. Losses occur through walls, ceilings, and floors of a structure, and through cracks around windows and doors. The heat loss depends on the structure size, construction, design, physical condition, amount of insulation in the walls and ceilings, the assumed indoor temperature, and various other factors.

Heating Degree Days: A measure of the severity of the winter in a given locality: the more heating degree days, the colder the winters. Heating degree days (HDD) are the difference between 65 degrees F and the daily mean (average) temperature when the latter is less than 65 degrees F.

Heckling: To try to embarrass and annoy (someone speaking or performing in public) by questions, gibes, or objections; badger.

Height of Instrument (HI): The vertical distance from the station mark to the center of the trunnion axis of the total station or level.

Horizontal shear: One of three major forces acting on a beam; it is the tendency of the fibers of a beam to slide past each other in a horizontal direction. Represented by (Fv).

Hydraulic detention time: The average amount of time a particle of water stays within a treatment vessel. The hydraulic detention time can be calculated by dividing the vessel volume by the flowrate.

Impact loads: Dynamic forces applied by live loads; because they are considered related to live loads, they are generally taken as a fraction of the live loads causing them.

Indeterminant beam: A beam with more than three support reaction forces. The three equilibrium equations are not sufficient to solve for all of the reactions. If a beam has three support reactions, it is said to be determinate.

Influent: Water or wastewater, partially or completely treated, or in its natural state that flows into a reservoir, tank, treatment component or disposal component.

Infrastructure: Basic installations, such as roads, railways, or factories that determine the economic power of a country, city, or town.

Introduction: Something spoken, written, or otherwise presented at the beginning of a presentation or written piece; used in presenting a person.

Irrigation: A process to supply something, such as dry land with water by means of ditches, pipes, or streams; to water artificially.

Jack stud: A wall member that is cut shorter than other studs to allow for an opening, such as a window (also called a cripple stud).

Junction box: A metal or plastic container that protects electrical wiring splices in conductors or joints in a run.

Juried presentation: A showing or viewing of something that has been assessed by a group of judges or evaluators.

Kaolin: A fine, white clay used in ceramics and refectories and as a filler or coating for paper and textiles. This clay is formed by the weathering of pegmatities or mica schists from the acids in ground water.

Land surveying: The process of measuring and locating physical entities on a plot of land to obtain a legal description.

Landscape design: The aesthetic improvement of land with the use of existing resources and the addition of plant material as needed.

Landscape horticulturist: A person whose profession is the cultivation of fruits, vegetables, flowers, or ornamental plants for decorative and functional alteration and planting of grounds.

Lateral loads: Sideways directed loads sustained by a structure that may be caused by winds or seismic activity.

Least squares: A method of determining the curve that best describes the relationship between expected and observed sets of data by minimizing the sums of the squares of deviation between observed and expected values. It is a process used to determine the best fit of a line or curve (depending on whether a person is using linear, non linear, damped, etc.) to a matrix of data points used in prediction.

Legal description: A written passage or statement that describes property; may be one of three types: metes and bounds, rectangular survey system, and lot and block.

Lending institution: Organization that is in the business of providing monetary funds for individuals or companies needing funds.

Leveling base: A foundation or area designed to level surveying instruments prior to use; four leveling screws are used.

Leveling Rod or Target rod: A device with a graduated scale in 1/10ths or 1/100ths of feet that is focused on through the telescope.

Line: A sense of direction or movement in the design of a structure which helps to relate it to the site and the natural surroundings.

Live load: Changing (live) weights on a structure in need of support, such as people, furniture, rain, or snow.

Load paths: The direction a force will follow along structural members to reach its foundation and ultimately the ground supporting the foundation.

Long span: A one-story structure with a span greater than 12 to 15 m and large free spaces between columns.

Materials: The products that are used to protect the exterior of the building from weather, such as roofing, wall coverings, doors, and windows.

Mat (Raft) foundations: A foundation used when soil bearing is relatively low or where loads are heavy in relation to soil-bearing capacities. This foundation type is essentially one large footing under an entire building, which distributes the load over the entire mat. A mat is called a raft foundation when it is placed deep enough in the soil that the soil removed during excavation equals most or all of the building's weight.

Models: A model, or mock-up, is a three-dimensional representation of an architectural design solution that is used to help communicate design concepts. The model can either be a physical model or a computer-generated model of the design.

Moment: Tendency to rotate about a point determined by the product of a force multiplied by the distance from this force to this point.

Monument: A known reference point on an immovable object used to reference topographical data usually identified by a brass circle with data inscribed on it.

Multi-Family: Distinction given in building codes to a structure where more than one family unit would reside.

National Geodetic Survey (NGS): A federal government activity that is responsible for national programs in geodesy and geodetic surveying. NGS is a division under the National Ocean Service of the National Oceanic and Atmospheric Administration (NOAA) within the Department of Commerce.

NAVD 88: The North American Vertical Datum of 1988 is a vertical reference datum, which superseded NGVD 1929.

Overhang beam: A beam supported with two supports, one or both supports are not located at the end of the beam.

P & Z Board: Local planning and zoning committee that is comprised of community individuals who make decisions governing the development of property within the community.

Panel box: The electrical enclosure where the service is connected to the individual circuits in the structure.

Particle board: A formed panel consisting of particles of wood flakes, chips, and shavings and bonded together with synthetic resin glue. Used for countertop or veneer panel underlayment.

Peer evaluation: Process of checking another's work against the requirements that have been given and giving constructive feedback.

Perspective Drawings: A type of pictorial drawing that provides the illusion of depth by converging all horizontal lines which represent the object's depth to a single vanishing point on the horizon (for one-point perspectives) or to two vanishing points on the horizon (for a two-point perspective). Additional Information: In architectural drawing, one-point perspectives are most commonly used for drawing room interiors; two-point perspectives are used most often to illustrate the exterior of a structure: and three-point perspectives are used for exterior illustrations that also require the illusion of height, such as in a tall building.

Photogrammetry: The science of obtaining reliable information about physical objects through the use of recording, measuring, and interpreting photographic images.

Pile foundations: Deep foundations acting like large nails that are hammered into the soil wit/;h pile drivers to deliver the structure load into a greater mass of soil, or to deliver the loads to a stiffer soil or bedrock stratum.

Pile: A heavy beam of timber, concrete, or steel, driven into the earth as a foundation or support for a structure.

Plastic Limit: The lowest moisture content at which a soil can be rolled into a thread 1/8 inch in diameter. Sands are non plastic and cannot be rolled.

Plat: A map of part of a city or township showing some specific area, such as a subdivision made up of several individual lots.

Point of Beginning (POB): The first point in an engineering project referenced to a bench mark, such as 0+00.

Polyvinyl Chloride (PVC) Pipe: Pipe that is constructed with a polymer formed by polymerization of vinyl chloride monomer, sometimes called vinyl. The white PVC pipe is often found in structures and used for gravity pipe systems such as wastewater drains. Green PVC pipe is used for gravity sanitary sewers.

Poorly Graded: Soil classification where there is only one size, uniformly graded, or a soil that contains only a few differently sized particles, gap graded.

Portfolio: A written record of the development of a project from inception to completion. The three types of portfolios are formative, summative, and marketing.

Position: The coordinates, in a horizontal reference system, which identify a station mark or feature. Latitude and longitude, and Northing and Easting are examples of position coordinates in systems used in surveying.

Precast Concrete: Concrete building components which are formed and cured at a factory and then transported to a work site for erection.

Principles of design: The basic rules or standards that determine a good design, such as form, function, and aesthetics.

Private: Structure or property development that has restricted or limited access for certain groups of people.

Private utilities: Any gravity sewer, force main, sewage treatment plant or water or electrical supply system that serves residential subdivisions or other groups of uses or structures and that is not owned and maintained by the public utilities.

Profile: The elevation (or front view) of property showing the vertical information created if a vertical slice is taken through the property.

Project: An undertaking that is usually large and encompasses planning, execution, and presentation to varying degrees as addressed in the scope.

Project notebooks: Notebooks documenting an undertaking that is evidence of design process, research, and final implementation of the design solution.

Proportion: A principle of design that deals with the size and shape of areas and their relationship to one another.

Protractor: A measurement device that is graduated in degrees and minutes and that is used for measuring horizontal angles.

Publicly Owned Treatment Works (POTW): Municipal owned water treatment or wastewater treatment facility.

Pump stations: Pumps, typically housed in buildings, which add energy to water distribution and sanitary sewer systems.

Radius (R): The perpendicular distance between the Transit line and the center of the curve, measured from the Point of Curve.

Regulations: Rules or ordinances that must be followed in the design of a structure or property development.

Reinforcement bars (rebar): Rods that are used for compressive strength; that is, the bar absorbs the push force.

Resources: Things needed to get a job done. The basic technological resources are tools and machines, materials, information, energy, capital, time, and people.

Rhythm: A principle of design that describes the illusion of flow or movement created by having a regularly repeated pattern of lines, planes, or surface treatments.

Right-of-Way (ROW): The strip or area of land around a state highway granted easement or fee paid to a local, state, or federal government agency.

Roof system: Primary system located on the top of a structure that protects its interior from the natural elements.

Rough Opening: The unfinished opening between framing members allowed for doors, windows, or other assemblies.

Scale: 1. A measuring device used to draw a proportionately reduced representation of a design. 2. A mineral deposit left by hard water.

Schedule Key: Sets of letters and numbers enclosed in geometric shapes that are used to cross reference a feature on a drawing to its corresponding part on a schedule, often referred to as a tag.

Scissor truss: A roof truss design characterized by two crossing diagonal bottom chords that are frequently used when a vaulted ceiling is desired.

Seasonal wind pattern: A design of natural origin of how the wind flows during different seasons of the year.

Section Modulus: The moment of inertia divided by the distance from the neutral axis to the extreme fiber of the cross section. If a member is rectangular then S = bd² / 6 (in3) is used in bending calculations, where b= width and d= depth. Does not work for I- shape.

Sections: Views that are formed by slicing a structure or part of a structure along a cutting plane line to show interior details.

Seismic load: Earthquake related forces that must be accounted for in the structural design; specified in the building codes.

Self-assessment: An assessment technique used to enhance learning and understanding through self-evaluation.

Septage: The biodegradable waste from septic tanks and similar treatment systems. Septage includes the sediments, water, grease, and scum pumped from a septic tank.

Septic System: A method to handle raw sewage on site; consists of piping from the structure to the tank, a tank to hold sewage where bacteria breaks it down, and a drain field where liquid is dispersed.

Service entrance: An entry to a structure or property that is used for delivery of goods and removal of refuse; usually located at the rear.

Service line: A pipe or conduit conveying a utility from a distribution main to the meter or entry point of any individual property.

Setback: The minimum legal distance from a property line or street where improvements to a site can be built or the minimum distance from the property lines to the front, rear, and sides of a structure.

Settling: To cause to sink, become compact, or come to rest; to cause (a liquid) to become clear by forming a sediment; to stabilize.

Shear: Stress that occurs when two forces from opposite directions are acting on the same member; tends to cut a member just as scissors cut paper.

Sheathing: A covering material placed over walls, floors, and roofs that serves as a backing for finishing materials.

Shock waves: Compressed waves that travel from an earthquake's hypocenter at different velocities impacting structures on the earth's surface; intensity varies according to the type of soil the wave is traveling through.

Simple beam: A beam with a uniform load evenly distributed over its entire length and supported at each end.

Single Family: Distinction given in building codes to a stand alone structure where only one family unit would reside.

Site: An area of land generally one plot or construction lot in size. The term site is synonymous with plot and lot.

Site Orientation: The placement of a structure on a property with certain environmental and physical factors taken into consideration.

Site plan: A map of a piece of land that may be used for any number of purposes. It shows the relationship between a structure and its physical surroundings. Also known as a plot or lot plan.

Slope: The relationship of the rise to the run expressed as a proportion or a percent, for example 1/10 or 10%.

Sketches: A collection of freehand drawings that communicate an idea; three types: program, design, and thumbnail.

Soffit: A lowered ceiling, typically found in kitchens, halls, and bathrooms to allow for recessed lighting or HVAC ducts.

Solar Orientation: A way of indicating the exposure to the sun. Solar orientation provides for excellent exposure to the sun. Solar access refers to the availability of direct sunlight to a structure or construction site.

Sound Orientation: A way of indicating the exposure to sound. Sound orientation includes determining the sounds that the client will contend with and what other design components may be used to soften the sound impact, such as droning road noise.

Space planning: The process of listing functions to be performed within a design and developing relationships as to their placement taking into consideration the design criteria.

Specification Manuals: Reference materials specific in nature which provide additional information that is not given in the working drawings.

Spread foundation: Foundation where the structural load is spread out over a broad area under a building utilizing horizontal rebar mats to anchor the building as a whole or to anchor individual columns or sections separately. Spread foundation is sometimes called "footing foundations" or "spread footing" and is a frequent type of foundation utilized in low rise buildings.

Stable: The condition of a structural member that has been designed to handle the loads it will carry to prevent failure.

Station: A location sometimes called a Station Point, at the intersection of two Traverse lines. Stations are usually sectioned into 100 foot intervals with the hundreds separated from the tens and ones by a + sign. E.g. 3+27 would be 327 feet from the Point of Beginning.

Strain: To alter the relations between the parts of a structure or shape by applying an external force; deform.

Stress: Live or dead load acting on a structural member that results as the material resists the external force; internal force per unit area of the member's cross section.

Structural Engineer: A profession that studies and understands the basic principles that define and characterize the behavior of physical objects subjected to forces and the designs of such things as bridges, buildings, dams, and stadiums.

Structure: Something made up of interdependent parts in a definite pattern of organization; an interrelation of parts as determined by the general character of the whole.

Subfloor: The flooring surface that is laid on the floor joint and that serves as a base layer for the finished floor.

Symmetry: (1) Exact correspondence of form and constituent configuration on opposite sides of a dividing line or plane or about a center or an axis. (2) Beauty as a result of balance or harmonious arrangement.

Telescope level: A spirit (air bubble in fluid encased in a glass cylinder) level used for leveling the instrument.

Test boring: The process of removing a small diameter core of soil and earth to determine the subterranean features and composition.

Texture: A principle of design which refers to the roughness or smoothness, including reflective properties, of a material or object and its related physical and visual effects.

Three phase: Electrical supply utilizing 4 wires with three lines, each 120° out of phase with the others. Used for commercial or industrial utility; well suited to run heavy motors.

Top plate: The upper horizontal framing member used in residential wall construction, frequently being doubled to provide for stiffness and for support of joists or trusses above.

Topography: The configuration of a surface including its relief and the position of its natural and cultural features.

Total dynamic head (TDH): The pressure within a pipe system with the water in motion. TDH = Static head minus head loss.

Total Station: An electronic surveying instrument that combines angles and distance-measuring capabilities in a single unit.

Transportation Engineering: A profession that designs and analyzes transportation systems, such as highway construction, railways, airports, urban and suburban road networks, parking areas, and traffic control systems.

Trap: A device for sealing a passage against the escape of gases, especially a U-shaped or S-shaped bend in a drainpipe that prevents the return flow of sewer gas by means of a water barrier.

Tributary width: The accumulation of loads that are directed to a structural member; always half the distance between the beam to be designed and the next bearing point.

Truss: A rigid framework, to support a roof or bridge; made from shorter components connected in triangles with pin connections.

Ultraviolet Disinfection: A final treatment method in which partially treated effluent is exposed to ultraviolet light to kill pathogens and microorganisms.

Unity: A principle of design related to the commonality of the design or decorating pattern that ties a structure together.

Universal accessibility: A design to provide access with the mobility limited person in mind; Americans with Disabilities Act (ADA) 1997 and the International Code Council have specified guidelines that are to be followed.

USDA hardiness map: A map of the United States that shows the range of temperatures in zones for vegetation growth; used when identifying plant material to be used in landscaping.

Vent stack: Any vertical pipe in a waste water system whose purpose is to provide a pathway for built up gasses.

Vertical Curve (VC): The transition created when a road travels over a hilltop or down a valley and up again.

Viability analysis: Evaluation process that takes into account the factors that will influence and determine the successful implementation of a proposed project.

View Orientation: A visualization of mountains, city lights, water, or even a developed site, such as a golf course; is optimized in the site orientation.

Wall Section: A partial section that shows only typical roof, wall, floor and foundation information for one typical wall rather than the full structure.

Waste Treatment Engineering: The profession that is responsible for designing and analyzing waste water treatment facilities, such as sanitary waste, disposable waste, and water treatment facilities.

Wastewater: The spent or used water from an individual household, a community, or commercial establishment, which contains dissolved and suspended matter that is harmful to human health and the environment. Wastewater requires treatment to remove bacteria and pathogens, either through an onsite decentralized wastewater treatment system or a centralized municipal sewage system, before it can safely be released into the environment. Household wastewater includes liquid-solid mixtures from toilets, sinks, showers, bathtubs, washing machines, dishwashers, and other drains.

Water Management Engineering: A profession that studies the use of hydraulic and hydrologic principles to design drainage systems, detention and retention ponds, navigational waterways, dams, and lakes.

Wetlands: Environmentally sensitive lands that have a large concentration of water on it that filters surface water back into the aquifer; usually have developmental restrictions placed upon their usage.

Wind load: A wind load is dynamic in nature because wind pressure, direction, and duration of wind are constantly changing. To accommodate this with wind load, a standard is used. Wind loads are treated as lateral loading on walls and in a downward pressure or uplift forces on roof planes.

Wind Orientation: Involves determining prevailing winds, which should be taken into account in the placement of a home or business.

Working drawings: The set of plans from which a structure will be built. Working drawings are the vehicle by which the designer graphically conveys the final design solution. Their size is dependent upon the scope and nature of the project.

Zenith Angle: The angle, measured in the vertical plane, between straight up (zero) and the target of observation. The horizontal, therefore, is 90 degrees.

Zoning: Clarifications for property development that govern the design and use of buildings, structures, and utilities within a municipality.

Bearings: would indicate a direction that is 56-degrees, 45-minutes from the south to the west. Directions with reference to one quadrant of a compass used to identify property boundaries in the metes and bounds system. Example: (S 56° 45' W)

Bentonite: 1. A very fine grained clay formed from decayed glass particles in volcanic rock which forms a watertight bond when compacted. One form of it, Sodium Bentonite, absorbs water and swells to about 20 times its original size. The other, Calcium Bentonite, does not change size. Bentonites are generally used to seal dump sites, pond bottoms and other areas used to contain water or chemicals. 2. An absorbent aluminum silicate clay formed from volcanic ash and used in various adhesives, cements, and ceramic fillers.

Blueprints: A generally accepted term for a set of printed drawings created by the Diazo reproduction process. Original blueprints were created by a wet chemical process that caused the background to be blue and any lines or printing to be white.

Bubble diagrams: Freehand sketches used to determine room locations, flow of traffic, and spatial relationships. They are the first step in the design process used to represent spatial relationships and placement of circulation flow.

Building Structure: The arrangement of parts to form a whole. A building structure's primary function is to support and redirect loads and forces safely to the ground. It constantly withstands forces of wind, effects of gravity, vibrations, and sometimes earthquakes.

Catchbasin: A device used to capture sediment, nutrients, metals, and hydrocarbons suspended in runoff from impervious surfaces before being conveyed to a storm sewer network or to another water-quality treatment system.

Chipboard: A flat construction material, made by using flat chips of wood bonded with formaldehyde glue; sometimes referred to as wafer board; term used in the construction industry for Oriented Strand Board (OSB). OSB was developed as an inexpensive replacement for plywood. It comes in several thicknesses only some of which are rated for sheathing or decks.

Construction Management Engineering: A profession that is responsible for managing and providing quality control, reviewing contracts, ordering materials, and hiring and scheduling sub-contractors for a structural engineering job.

Consumption-Based Methodology: One of two suggested systems that can be used to establish utility allowances. (See also engineering-based methodology.) This method is based on actual consumption data from utility bills or checked meter readings. Data is used to estimate the amount of energy or water a household should reasonably require.

Contractor: A person responsible for directing a project or a portion of the work on a project as in the case of a subcontractor; usually a legally binding agreement is signed and a bond posted to ensure completion.

Cooling Degree Days: A measure of the severity of the summer in a given locality: the more cooling degree days, the hotter the summers. Cooling degree days (CDD) are the difference between 65 degrees F and the daily mean (average) temperature when the latter is more than 65 degrees F.

Design Temperature Differential: The difference between the indoor temperature in winter and the outdoor design temperature in winter. The design temperature differential or design range is used in calculating the space heating requirements of a dwelling unit under the engineering-based methodology.

Determinant beam: A beam with three support reaction forces that can be determined by applying the three equilibrium equations. If a beam has more than three support reactions, it is said to be indeterminate.

Distribution panel: A section or division of a wall where the conductor from the meter base is connected to individual circuit breakers, which are connected to separate circuits for distribution to various locations throughout the structure.

Engineered beam: A long, thick piece of wood created from smaller wood pieces improving upon the normal capabilities of construction lumber. These products are composed of wood particles (veneer, wood chips, oriented strands, wafers, laminated dimensional lumber, and combinations thereof) bonded by long-lasting adhesives to ensure the structural integrity.

Engineering-Based Methodology: One of two suggested systems that can be used to establish utility allowances. (See also consumption-based methodology.) This method is based on engineering calculations and other technical information that is used to estimate the amount of energy or water a household should reasonably require.

Environmental Engineer: A sub-discipline of civil engineering that deals with the treatment of chemical, biological, and/or thermal waste, the purification of water and air, and the remediation of contaminated sites, due to prior waste disposal or accidental contamination. Environmental engineers are also involved in pollution reduction, green engineering, and industrial ecology. Environmental engineering is the modern term for Sanitary engineering. Some other terms in use are public health engineering and environmental health engineering.

Heat Loss: The rate of heat transfer in British Thermal Units (BTU) per hour from occupied space to the outdoors. Losses occur through walls, ceilings, and floors of a structure, and through cracks around windows and doors. The heat loss depends on the structure size, construction, design, physical condition, amount of insulation in the walls and ceilings, the assumed indoor temperature, and various other factors.

Heating Degree Days: A measure of the severity of the winter in a given locality: the more heating degree days, the colder the winters. Heating degree days (HDD) are the difference between 65 degrees F and the daily mean (average) temperature when the latter is less than 65 degrees F.

Indeterminant beam: A beam with more than three support reaction forces. The three equilibrium equations are not sufficient to solve for all of the reactions. If a beam has three support reactions, it is said to be determinate.

Least squares: A method of determining the curve that best describes the relationship between expected and observed sets of data by minimizing the sums of the squares of deviation between observed and expected values. It is a process used to determine the best fit of a line or curve (depending on whether a person is using linear, non linear, damped, etc.) to a matrix of data points used in prediction.

Mat (Raft) foundations: A foundation used when soil bearing is relatively low or where loads are heavy in relation to soil-bearing capacities. This foundation type is essentially one large footing under an entire building, which distributes the load over the entire mat. A mat is called a raft foundation when it is placed deep enough in the soil that the soil removed during excavation equals most or all of the building's weight.

Models: A model, or mock-up, is a three-dimensional representation of an architectural design solution that is used to help communicate design concepts. The model can either be a physical model or a computer-generated model of the design.

National Geodetic Survey (NGS): A federal government activity that is responsible for national programs in geodesy and geodetic surveying. NGS is a division under the National Ocean Service of the National Oceanic and Atmospheric Administration (NOAA) within the Department of Commerce.

Perspective Drawings: A type of pictorial drawing that provides the illusion of depth by converging all horizontal lines which represent the object's depth to a single vanishing point on the horizon (for one-point perspectives) or to two vanishing points on the horizon (for a two-point perspective). Additional Information: In architectural drawing, one-point perspectives are most commonly used for drawing room interiors; two-point perspectives are used most often to illustrate the exterior of a structure: and three-point perspectives are used for exterior illustrations that also require the illusion of height, such as in a tall building.

Pile foundations: Deep foundations acting like large nails that are hammered into the soil wit/;h pile drivers to deliver the structure load into a greater mass of soil, or to deliver the loads to a stiffer soil or bedrock stratum.

Polyvinyl Chloride (PVC) Pipe: Pipe that is constructed with a polymer formed by polymerization of vinyl chloride monomer, sometimes called vinyl. The white PVC pipe is often found in structures and used for gravity pipe systems such as wastewater drains. Green PVC pipe is used for gravity sanitary sewers.

Position: The coordinates, in a horizontal reference system, which identify a station mark or feature. Latitude and longitude, and Northing and Easting are examples of position coordinates in systems used in surveying.

Private utilities: Any gravity sewer, force main, sewage treatment plant or water or electrical supply system that serves residential subdivisions or other groups of uses or structures and that is not owned and maintained by the public utilities.

Section Modulus: The moment of inertia divided by the distance from the neutral axis to the extreme fiber of the cross section. If a member is rectangular then S = bd² / 6 (in3) is used in bending calculations, where b= width and d= depth. Does not work for I- shape.

Shock waves: Compressed waves that travel from an earthquake's hypocenter at different velocities impacting structures on the earth's surface; intensity varies according to the type of soil the wave is traveling through.

Solar Orientation: A way of indicating the exposure to the sun. Solar orientation provides for excellent exposure to the sun. Solar access refers to the availability of direct sunlight to a structure or construction site.

Sound Orientation: A way of indicating the exposure to sound. Sound orientation includes determining the sounds that the client will contend with and what other design components may be used to soften the sound impact, such as droning road noise.

Spread foundation: Foundation where the structural load is spread out over a broad area under a building utilizing horizontal rebar mats to anchor the building as a whole or to anchor individual columns or sections separately. Spread foundation is sometimes called "footing foundations" or "spread footing" and is a frequent type of foundation utilized in low rise buildings.

Station: A location sometimes called a Station Point, at the intersection of two Traverse lines. Stations are usually sectioned into 100 foot intervals with the hundreds separated from the tens and ones by a + sign. E.g. 3+27 would be 327 feet from the Point of Beginning.

Structural Engineer: A profession that studies and understands the basic principles that define and characterize the behavior of physical objects subjected to forces and the designs of such things as bridges, buildings, dams, and stadiums.

Transportation Engineering: A profession that designs and analyzes transportation systems, such as highway construction, railways, airports, urban and suburban road networks, parking areas, and traffic control systems.

Universal accessibility: A design to provide access with the mobility limited person in mind; Americans with Disabilities Act (ADA) 1997 and the International Code Council have specified guidelines that are to be followed.

Wastewater: The spent or used water from an individual household, a community, or commercial establishment, which contains dissolved and suspended matter that is harmful to human health and the environment. Wastewater requires treatment to remove bacteria and pathogens, either through an onsite decentralized wastewater treatment system or a centralized municipal sewage system, before it can safely be released into the environment. Household wastewater includes liquid-solid mixtures from toilets, sinks, showers, bathtubs, washing machines, dishwashers, and other drains.

Wind load: A wind load is dynamic in nature because wind pressure, direction, and duration of wind are constantly changing. To accommodate this with wind load, a standard is used. Wind loads are treated as lateral loading on walls and in a downward pressure or uplift forces on roof planes.

Working drawings: The set of plans from which a structure will be built. Working drawings are the vehicle by which the designer graphically conveys the final design solution. Their size is dependent upon the scope and nature of the project.

Bentonite: 1. A very fine grained clay formed from decayed glass particles in volcanic rock which forms a watertight bond when compacted. One form of it, Sodium Bentonite, absorbs water and swells to about 20 times its original size. The other, Calcium Bentonite, does not change size. Bentonites are generally used to seal dump sites, pond bottoms and other areas used to contain water or chemicals. 2. An absorbent aluminum silicate clay formed from volcanic ash and used in various adhesives, cements, and ceramic fillers.

Chipboard: A flat construction material, made by using flat chips of wood bonded with formaldehyde glue; sometimes referred to as wafer board; term used in the construction industry for Oriented Strand Board (OSB). OSB was developed as an inexpensive replacement for plywood. It comes in several thicknesses only some of which are rated for sheathing or decks.

Consumption-Based Methodology: One of two suggested systems that can be used to establish utility allowances. (See also engineering-based methodology.) This method is based on actual consumption data from utility bills or checked meter readings. Data is used to estimate the amount of energy or water a household should reasonably require.

Engineered beam: A long, thick piece of wood created from smaller wood pieces improving upon the normal capabilities of construction lumber. These products are composed of wood particles (veneer, wood chips, oriented strands, wafers, laminated dimensional lumber, and combinations thereof) bonded by long-lasting adhesives to ensure the structural integrity.

Engineering-Based Methodology: One of two suggested systems that can be used to establish utility allowances. (See also consumption-based methodology.) This method is based on engineering calculations and other technical information that is used to estimate the amount of energy or water a household should reasonably require.

Environmental Engineer: A sub-discipline of civil engineering that deals with the treatment of chemical, biological, and/or thermal waste, the purification of water and air, and the remediation of contaminated sites, due to prior waste disposal or accidental contamination. Environmental engineers are also involved in pollution reduction, green engineering, and industrial ecology. Environmental engineering is the modern term for Sanitary engineering. Some other terms in use are public health engineering and environmental health engineering.

Heat Loss: The rate of heat transfer in British Thermal Units (BTU) per hour from occupied space to the outdoors. Losses occur through walls, ceilings, and floors of a structure, and through cracks around windows and doors. The heat loss depends on the structure size, construction, design, physical condition, amount of insulation in the walls and ceilings, the assumed indoor temperature, and various other factors.

Least squares: A method of determining the curve that best describes the relationship between expected and observed sets of data by minimizing the sums of the squares of deviation between observed and expected values. It is a process used to determine the best fit of a line or curve (depending on whether a person is using linear, non linear, damped, etc.) to a matrix of data points used in prediction.

Mat (Raft) foundations: A foundation used when soil bearing is relatively low or where loads are heavy in relation to soil-bearing capacities. This foundation type is essentially one large footing under an entire building, which distributes the load over the entire mat. A mat is called a raft foundation when it is placed deep enough in the soil that the soil removed during excavation equals most or all of the building's weight.

Perspective Drawings: A type of pictorial drawing that provides the illusion of depth by converging all horizontal lines which represent the object's depth to a single vanishing point on the horizon (for one-point perspectives) or to two vanishing points on the horizon (for a two-point perspective). Additional Information: In architectural drawing, one-point perspectives are most commonly used for drawing room interiors; two-point perspectives are used most often to illustrate the exterior of a structure: and three-point perspectives are used for exterior illustrations that also require the illusion of height, such as in a tall building.

Spread foundation: Foundation where the structural load is spread out over a broad area under a building utilizing horizontal rebar mats to anchor the building as a whole or to anchor individual columns or sections separately. Spread foundation is sometimes called "footing foundations" or "spread footing" and is a frequent type of foundation utilized in low rise buildings.

Wastewater: The spent or used water from an individual household, a community, or commercial establishment, which contains dissolved and suspended matter that is harmful to human health and the environment. Wastewater requires treatment to remove bacteria and pathogens, either through an onsite decentralized wastewater treatment system or a centralized municipal sewage system, before it can safely be released into the environment. Household wastewater includes liquid-solid mixtures from toilets, sinks, showers, bathtubs, washing machines, dishwashers, and other drains.

Bentonite: 1. A very fine grained clay formed from decayed glass particles in volcanic rock which forms a watertight bond when compacted. One form of it, Sodium Bentonite, absorbs water and swells to about 20 times its original size. The other, Calcium Bentonite, does not change size. Bentonites are generally used to seal dump sites, pond bottoms and other areas used to contain water or chemicals. 2. An absorbent aluminum silicate clay formed from volcanic ash and used in various adhesives, cements, and ceramic fillers.

Environmental Engineer: A sub-discipline of civil engineering that deals with the treatment of chemical, biological, and/or thermal waste, the purification of water and air, and the remediation of contaminated sites, due to prior waste disposal or accidental contamination. Environmental engineers are also involved in pollution reduction, green engineering, and industrial ecology. Environmental engineering is the modern term for Sanitary engineering. Some other terms in use are public health engineering and environmental health engineering.

Perspective Drawings: A type of pictorial drawing that provides the illusion of depth by converging all horizontal lines which represent the object's depth to a single vanishing point on the horizon (for one-point perspectives) or to two vanishing points on the horizon (for a two-point perspective). Additional Information: In architectural drawing, one-point perspectives are most commonly used for drawing room interiors; two-point perspectives are used most often to illustrate the exterior of a structure: and three-point perspectives are used for exterior illustrations that also require the illusion of height, such as in a tall building.

Wastewater: The spent or used water from an individual household, a community, or commercial establishment, which contains dissolved and suspended matter that is harmful to human health and the environment. Wastewater requires treatment to remove bacteria and pathogens, either through an onsite decentralized wastewater treatment system or a centralized municipal sewage system, before it can safely be released into the environment. Household wastewater includes liquid-solid mixtures from toilets, sinks, showers, bathtubs, washing machines, dishwashers, and other drains.

Environmental Engineer: A sub-discipline of civil engineering that deals with the treatment of chemical, biological, and/or thermal waste, the purification of water and air, and the remediation of contaminated sites, due to prior waste disposal or accidental contamination. Environmental engineers are also involved in pollution reduction, green engineering, and industrial ecology. Environmental engineering is the modern term for Sanitary engineering. Some other terms in use are public health engineering and environmental health engineering.

Perspective Drawings: A type of pictorial drawing that provides the illusion of depth by converging all horizontal lines which represent the object's depth to a single vanishing point on the horizon (for one-point perspectives) or to two vanishing points on the horizon (for a two-point perspective). Additional Information: In architectural drawing, one-point perspectives are most commonly used for drawing room interiors; two-point perspectives are used most often to illustrate the exterior of a structure: and three-point perspectives are used for exterior illustrations that also require the illusion of height, such as in a tall building.

Wastewater: The spent or used water from an individual household, a community, or commercial establishment, which contains dissolved and suspended matter that is harmful to human health and the environment. Wastewater requires treatment to remove bacteria and pathogens, either through an onsite decentralized wastewater treatment system or a centralized municipal sewage system, before it can safely be released into the environment. Household wastewater includes liquid-solid mixtures from toilets, sinks, showers, bathtubs, washing machines, dishwashers, and other drains.