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Overview of Designing Overview of Designing Building for Fire ResistanceBuilding for Fire Resistance
Philip DiNennoPhilip DiNennoCraig BeylerCraig Beyler
Hughes Associates, Inc.Hughes Associates, Inc.Presented at NIST Workshop Presented at NIST Workshop
Research Needs for Fire Resistance DeterminationResearch Needs for Fire Resistance DeterminationAnd Performance PredictionAnd Performance Prediction
February 19, 2002February 19, 2002
OverviewOverview
Brief HistoryBrief History Current StatusCurrent Status Current Role in Fire SafetyCurrent Role in Fire Safety Current StatusCurrent Status Status Circa 1965-1970Status Circa 1965-1970 Needs for Science Based Structural Needs for Science Based Structural
F.P.F.P.
HistoryHistory
18901890 Denver – 1st fire endurance tests Denver – 1st fire endurance tests (floors)(floors)
NYC Bldg. Dept Floor systemNYC Bldg. Dept Floor system 2000° F (1093°C), 5 hours2000° F (1093°C), 5 hours 150 lb/ft2 150 lb/ft2 600 lb/ft2 (24 hrs)600 lb/ft2 (24 hrs) Led to requirements In NYC BCLed to requirements In NYC BC
Columbia U FurnaceColumbia U Furnace
18961896
19021902
HistoryHistory
1906 1906 ASTM — Committee after Balt. ASTM — Committee after Balt. firefire 1700°F, 150 lb/ft1700°F, 150 lb/ft22 — 600 lb/ft — 600 lb/ft22
11stst ASTM Standards ASTM Standards FM, NBFU, NIST >furnaces At FM, NBFU, NIST >furnaces At
ULUL Column TestColumn Test
1908-19091908-1909
19101910
19171917
HistoryHistory
19181918 ASTM C-5ASTM C-5 Floor and WallFloor and Wall Time related end points (temp and Time related end points (temp and
mech)mech) Test for 25% Safety Factor wrt timeTest for 25% Safety Factor wrt time Standard TTCStandard TTC
NBS/INGBERG – Fuel Load & Fire NBS/INGBERG – Fuel Load & Fire Resistance Time equivalencyResistance Time equivalency Fuel Load- Fire resistance time Fuel Load- Fire resistance time
“Equivalence”“Equivalence”
19221922
Role of Fire Resistance in Role of Fire Resistance in Fire SafetyFire Safety
Prevent Building CollapsePrevent Building Collapse Prevent External SpreadPrevent External Spread Vertical/Horizontal Fire SpreadVertical/Horizontal Fire Spread Means of EgressMeans of Egress Smoke ControlSmoke Control Firefighter SafetyFirefighter Safety
Current StatusCurrent Status
Fire Resistance RequirementFire Resistance Requirement Established by building code – function ofEstablished by building code – function of
OccupancyOccupancy Height/areaHeight/area Sprinkler protectionSprinkler protection
Testing per UL, NFPA, ASTMTesting per UL, NFPA, ASTM Listing by UL/FM et alListing by UL/FM et al Find requirement in hoursFind requirement in hours Look it up in a listing bookLook it up in a listing book Spec itSpec it Maybe Inspect itMaybe Inspect it
CurrentCurrent
Fire Exposure:Fire Exposure: Standard Time Temp Cure (circa 1920) in furnaceStandard Time Temp Cure (circa 1920) in furnace
Thermal ResponseThermal Response Temperature Measurement from SampleTemperature Measurement from Sample
MechanicalMechanical If loaded, can’t open or collapseIf loaded, can’t open or collapse No current limit on deflectionNo current limit on deflection No connectionsNo connections
Physical PropertiesPhysical Properties Adhesion, cohesionAdhesion, cohesion No vibration,impact,hardness,shock,impact,blast etc testingNo vibration,impact,hardness,shock,impact,blast etc testing
ReliabilityReliability Unknown and variableUnknown and variable Implicitly treated though listing/approvalImplicitly treated though listing/approval
In-Situ TestingIn-Situ Testing Done in small % of casesDone in small % of cases Usually when problem is obviousUsually when problem is obvious
Time-Time-temperature temperature Curve From Curve From “Standard “Standard
Methods Of Methods Of Fire Tests Of Fire Tests Of
Building Building Construction Construction And Materials And Materials (ASTM E119-(ASTM E119-
80)80)
The “Fire Severity” ConceptThe “Fire Severity” Concept
Relationship Between Fire Load and Fire Relationship Between Fire Load and Fire EnduranceEndurance
Average Fire Load Average Fire Load psf*psf* kg/mkg/m22
Equivalent Fire Equivalent Fire Endurance (hours)Endurance (hours)
55 24.424.4 ½½
7½7½ 36.636.6 ¾¾
1010 48.848.8 11
1515 73.273.2 1½1½
2020 97.697.6 22
3030 146.5146.5 33
4040 195.3195.3 4½4½
5050 244.1244.1 66
6060 292.9292.9 7½7½
* Determined on the basis of a potential heat of approximately 8000 Btu’s per pound
Determination of Equivalent Fire Endurance Determination of Equivalent Fire Endurance TimeTime
Materials/Systems Currently Materials/Systems Currently UsedUsed
Sprayed FiberSprayed Fiber CementitiousCementitious MasticMastic Intumescent PaintIntumescent Paint MembraneMembrane
Suspended ceilingsSuspended ceilings Drywall assembliesDrywall assemblies
Concrete encasementConcrete encasement TileTile Plaster/lathPlaster/lath
Effect of Window Area on Fire Temperatures Effect of Window Area on Fire Temperatures During Burnout Tests with Natural During Burnout Tests with Natural
VentilationVentilation
State of Art (circa 1965–State of Art (circa 1965–1975)1975)
Fire ExposureFire Exposure Design exposure curvesDesign exposure curves Post-flashoverPost-flashover Ventilation controlledVentilation controlled Insulation properties of wall liningsInsulation properties of wall linings
Thermal ResponseThermal Response Critical temperatureCritical temperature
Columns, beamsColumns, beams 1-D analytical1-D analytical 2-D finite differences schemes2-D finite differences schemes
State of Art (circa 1965–State of Art (circa 1965–1975)1975)
Mechanical ResponseMechanical Response Column bucklingColumn buckling Beam deflectionBeam deflection Truss deflectionTruss deflection
Physical propertiesPhysical properties Transport & Mechanical properties as a F (T)Transport & Mechanical properties as a F (T)
Question: Capability for 30-35 years…integrated Question: Capability for 30-35 years…integrated into design guides and never utilized in US into design guides and never utilized in US regulationsregulations
1975-19801975-1980
3-D Finite Element Heat Transfer 3-D Finite Element Heat Transfer ModelModel
Structural Response Model (FASBUS)Structural Response Model (FASBUS) Model of Post Flashover Fires Model of Post Flashover Fires
( COMPF)( COMPF)
Needs for Science-Based Needs for Science-Based Structural Fire Protection Structural Fire Protection
DesignDesign Design fire exposureDesign fire exposure Thermal/Mechanical Response of Thermal/Mechanical Response of
Insulation SystemsInsulation Systems Structural Performance in FireStructural Performance in Fire Test methodsTest methods Performance CriteriaPerformance Criteria Technology TransferTechnology Transfer
Science-Based Structural Science-Based Structural Fire Protection DesignFire Protection Design
Building CodeBuilding CodeRequirementsRequirements
ListingsListings - Engineering data - Engineering data - Furnace validation - Furnace validation
ArchitecturalArchitecturalDesignDesign
StructuralStructuralDesignDesign
Design FireDesign FireExposureExposure
Passive FPPassive FPConceptual DesignConceptual Design
Passive FPPassive FPDetailed DesignDetailed DesignThermal/Mech. AnalysisThermal/Mech. Analysis
Structural FireStructural FirePerformance AnalysisPerformance Analysis
Evaluate PerformanceEvaluate Performance
Design Fire ExposureDesign Fire Exposure
Modern fire load survey dataModern fire load survey data Combined local/global fire exposure Combined local/global fire exposure
characterization, i.e. beyond well characterization, i.e. beyond well stirredstirred
Thermal/Mechanical Thermal/Mechanical Response of Insulation Response of Insulation
SystemsSystems Institutionalized thermal properties Institutionalized thermal properties
test methodstest methods Test methods and performance Test methods and performance
criteria for mechanical response; non-criteria for mechanical response; non-fire, impact loading, fire exposurefire, impact loading, fire exposure
Fire barrier performance- must Fire barrier performance- must address along with structural frame address along with structural frame performanceperformance
Structural Performance in Structural Performance in FireFire
Assess needs for full structural frame Assess needs for full structural frame analysis vs more detailed local analysis vs more detailed local deformation analysisdeformation analysis
Assessment of connection Assessment of connection performanceperformance
Test MethodsTest Methods
Need full compliment of test Need full compliment of test methods for engineering propertiesmethods for engineering properties
Revisit furnace testing methods:Revisit furnace testing methods:-exposure should be severe (1709)-exposure should be severe (1709)-test should be a validation of -test should be a validation of
engineering methodsengineering methods-revisit the relationship between the -revisit the relationship between the test test and real structural framesand real structural frames
Performance CriteriaPerformance Criteria
What are we trying to achieve?What are we trying to achieve? Acceptable local performanceAcceptable local performance Acceptable global performanceAcceptable global performance Risk, reliability, and relationship to Risk, reliability, and relationship to
the total fire protection designthe total fire protection design Inspection, Testing, and Maintenance Inspection, Testing, and Maintenance
(ITM)(ITM)
Technology TransferTechnology Transfer“The Real Problem”“The Real Problem”
Develop a broad consensus for the Develop a broad consensus for the need to change how we do SFPneed to change how we do SFP
Codify SFP design practiceCodify SFP design practice Formulate building code Formulate building code
requirementsrequirements Educate engineers, architects, AHJ’sEducate engineers, architects, AHJ’s
Needs for Science-Based Needs for Science-Based Structural Fire Protection Structural Fire Protection
DesignDesign Design fire exposureDesign fire exposure Thermal/Mechanical Response of Thermal/Mechanical Response of
Insulation SystemsInsulation Systems Structural Performance in FireStructural Performance in Fire Test methodsTest methods Performance CriteriaPerformance Criteria Technology TransferTechnology Transfer
Test MethodsTest Methods
Need full compliment of test Need full compliment of test methods for engineering propertiesmethods for engineering properties
Revisit furnace testing methods:Revisit furnace testing methods:-exposure should be severe (1709)-exposure should be severe (1709)-test should be a validation of -test should be a validation of
engineering methodsengineering methods-revisit the relationship between the -revisit the relationship between the test test and real structural framesand real structural frames
SummarySummary
Science-based structural fire Science-based structural fire protection is clearly technically protection is clearly technically achievableachievable
It will require a total reexamination It will require a total reexamination of the SFP process from listing, to of the SFP process from listing, to design, to ITMdesign, to ITM
The payoff? - known, cost effective The payoff? - known, cost effective performance and safetyperformance and safety
Technology TransferTechnology Transfer“The Real Problem”“The Real Problem”
Develop a broad consensus for the Develop a broad consensus for the need to change how we do SFPneed to change how we do SFP
Codify SFP design practiceCodify SFP design practice Formulate building code Formulate building code
requirementsrequirements Educate engineers, architects, AHJ’sEducate engineers, architects, AHJ’s