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ISSN: 2277-3754 ISO 9001:2008 Certified International Journal of Engineering and Innovative Technology (IJEIT) Volume 2, Issue 10, April 2013 149 Analysis of Reinforced Beam-Column Joint Subjected to Monotonic Loading S. S. Patil, S. S. Manekari Abstract - The common regions of intersecting elements are called joints. Whenever the area of these regions is limited, as in case of linear elements (beams and columns) framing into each other, it is essential to verify their maximum shear stress, as well as the minimum shear stress and deformations (displacements) of beam column joint region. The various research studies focused on corner and exterior beam column joints and their behavior, support conditions of beam-column joints i. e .both ends hinged and fixed, stiffness variation of the joint .In this study various parameters are studied for monotonically loaded exterior and corner reinforced concrete beam column joint. The corner as well as exterior beam-column joint is analyzed with varying stiffness of beam-column joint. The behavior of exterior and corner beam-column joint subjected to monotonic loading is different. Various graphs like load vs. displacement (deformations), Maximum stress, Stiffness variations i.e. joint ratios of beam-column joints are plotted. Index Terms - Corner and Exterior Joints, Joint Ratios, Monotonic Load, Stiffness Variations. I. INTRODUCTION Earthquakes are one of the most feared natural phenomena that are relatively unexpected and whose impact is sudden due to the almost instantaneous destruction that a major earthquake can produce. Severity of ground shaking at a given location during an earthquake can be minor, moderate and strong which relatively speaking occur frequently, occasionally an rarely respectively. Design and construction of a building to resist the rare earthquake shaking that may come only once in 500 years or even once in 2000 years at a chosen project site even though life of the building itself may be only 50 to 100 years is too robust and also too expensive. Hence, the main intention is to make building earthquake-resistant that resist the effect of ground shaking although it may get damaged severely but would not collapse during even the strong earthquake. Thus, the safety of people and contents is assured in earthquake-resistant buildings. This is a major objective of seismic design codes throughout the world. The performance of structures in earthquakes indicates that most structures, system and components, if properly designed and detailed, have a significant capacity to absorb energy when deformed beyond their elastic limits. Experience with the behavior of reinforced concrete beam- column joints in actual earthquakes is limited. To fully realize the benefits of ductile behavior of reinforced concrete frame structures, instabilities due to large deflections and brittle failure of structural elements must be prevented under the most severe expected earthquake ground motions. II. LITERATURE REVIEW As it is explained above the strength of beam-column joint plays a very important role in the strength of the structure, here the literature survey is carried out to have the information about the Monotonic Loading applied to the beam-column joint. The literature review covers research papers based on beam-column joints. Vladmir Guilherne Haach, Ana Lucia Home De Cresce El Debs, Mounir Khalil El Debs [1] This paper investigates the influence of the column axial load on the joint shear strength through numerical simulations. The numerical study is performed through the software ABAQUS, based on Finite Element Method. A comparison of the numerical and experimental results is presented in order to validate the simulation. The results showed that the column axial load made the joint more stiff but also introduced stresses in the beam longitudinal reinforcement. A more uniform stress distribution in the joint region is obtained when the stirrup ratio is increased. Furthermore, some tension from the top beam longitudinal reinforcement is absorbed by the stirrups located at the upper part of the joint. This paper gives the affect of stirrup ratio to exterior beam-column joints where the beam is loaded monotonically. Hegger Josef,Sherif Alaa and Roeser Wolfgang [8] here authors have carried out Monotonic tests on beam-column joints which showed the failure of the connection can either be in the beam(bending failure) or inside the joint(shear and bond failures).The behavior of exterior beam-column joints is different from that of interior connections. The model has been calibrated using a database with more than 200 static load tests. The reported test results as well as test results from the literature were used to study the behavior of exterior and interior beam-column connections. The shear strength of an exterior beam-column connection decreases with increasing joint slenderness. Murty.C. V. R, Durgesh C. Rai, K. K. Bajpai, and Sudhir K. Jain [14] described an experimental study of beam-column joints in frames common in pre-seismic code/gravity-designed reinforced concrete (RC) frame buildings. Exterior RC joint sub assemblages are studied with four details of longitudinal beam bar anchorage and three details of transverse joint reinforcement. All these specimens showed low ductility and poor energy dissipation with excessive shear cracking of the joint core. Uma. S. R. and Meher Prasad. A [15] discussed the general behavior of common types of joints in reinforced concrete moment resisting frames. The mechanisms involved in joint performance with respect to bond and shear transfer are critically reviewed and discussed in detail. The factors impacting the bond transfer within the joint appears to be well related to the level of axial load and the amount of
Transcript
  • ISSN: 2277-3754

    ISO 9001:2008 Certified International Journal of Engineering and Innovative Technology (IJEIT)

    Volume 2, Issue 10, April 2013

    149

    Analysis of Reinforced Beam-Column Joint

    Subjected to Monotonic Loading S. S. Patil, S. S. Manekari

    Abstract - The common regions of intersecting elements are

    called joints. Whenever the area of these regions is limited, as in

    case of linear elements (beams and columns) framing into each

    other, it is essential to verify their maximum shear stress, as well

    as the minimum shear stress and deformations (displacements)

    of beam column joint region. The various research studies

    focused on corner and exterior beam column joints and their

    behavior, support conditions of beam-column joints i. e .both

    ends hinged and fixed, stiffness variation of the joint .In this

    study various parameters are studied for monotonically loaded

    exterior and corner reinforced concrete beam column joint. The

    corner as well as exterior beam-column joint is analyzed with

    varying stiffness of beam-column joint. The behavior of exterior

    and corner beam-column joint subjected to monotonic loading is

    different. Various graphs like load vs. displacement

    (deformations), Maximum stress, Stiffness variations i.e. joint

    ratios of beam-column joints are plotted.

    Index Terms - Corner and Exterior Joints, Joint Ratios,

    Monotonic Load, Stiffness Variations.

    I. INTRODUCTION

    Earthquakes are one of the most feared natural

    phenomena that are relatively unexpected and whose

    impact is sudden due to the almost instantaneous

    destruction that a major earthquake can produce. Severity

    of ground shaking at a given location during an earthquake

    can be minor, moderate and strong which relatively

    speaking occur frequently, occasionally an rarely

    respectively. Design and construction of a building to resist

    the rare earthquake shaking that may come only once in

    500 years or even once in 2000 years at a chosen project

    site even though life of the building itself may be only 50 to

    100 years is too robust and also too expensive. Hence, the

    main intention is to make building earthquake-resistant that

    resist the effect of ground shaking although it may get

    damaged severely but would not collapse during even the

    strong earthquake. Thus, the safety of people and contents

    is assured in earthquake-resistant buildings. This is a major

    objective of seismic design codes throughout the world.

    The performance of structures in earthquakes indicates that

    most structures, system and components, if properly

    designed and detailed, have a significant capacity to absorb

    energy when deformed beyond their elastic limits.

    Experience with the behavior of reinforced concrete beam-

    column joints in actual earthquakes is limited. To fully

    realize the benefits of ductile behavior of reinforced

    concrete frame structures, instabilities due to large

    deflections and brittle failure of structural elements must be

    prevented under the most severe expected earthquake

    ground motions.

    II. LITERATURE REVIEW

    As it is explained above the strength of beam-column

    joint plays a very important role in the strength of the

    structure, here the literature survey is carried out to have the

    information about the Monotonic Loading applied to the

    beam-column joint. The literature review covers research

    papers based on beam-column joints. Vladmir Guilherne

    Haach, Ana Lucia Home De Cresce El Debs, Mounir Khalil

    El Debs [1]

    This paper investigates the influence of the

    column axial load on the joint shear strength through

    numerical simulations. The numerical study is performed

    through the software ABAQUS, based on Finite Element

    Method. A comparison of the numerical and experimental

    results is presented in order to validate the simulation. The

    results showed that the column axial load made the joint

    more stiff but also introduced stresses in the beam

    longitudinal reinforcement. A more uniform stress

    distribution in the joint region is obtained when the stirrup

    ratio is increased. Furthermore, some tension from the top

    beam longitudinal reinforcement is absorbed by the stirrups

    located at the upper part of the joint. This paper gives the

    affect of stirrup ratio to exterior beam-column joints where

    the beam is loaded monotonically. Hegger Josef,Sherif Alaa

    and Roeser Wolfgang[8]

    here authors have carried out

    Monotonic tests on beam-column joints which showed the

    failure of the connection can either be in the beam(bending

    failure) or inside the joint(shear and bond failures).The

    behavior of exterior beam-column joints is different from

    that of interior connections. The model has been calibrated

    using a database with more than 200 static load tests. The

    reported test results as well as test results from the literature

    were used to study the behavior of exterior and interior

    beam-column connections. The shear strength of an exterior

    beam-column connection decreases with increasing joint

    slenderness. Murty.C. V. R, Durgesh C. Rai, K. K. Bajpai,

    and Sudhir K. Jain [14]

    described an experimental study of

    beam-column joints in frames common in pre-seismic

    code/gravity-designed reinforced concrete (RC) frame

    buildings. Exterior RC joint sub assemblages are studied

    with four details of longitudinal beam bar anchorage and

    three details of transverse joint reinforcement. All these

    specimens showed low ductility and poor energy

    dissipation with excessive shear cracking of the joint core.

    Uma. S. R. and Meher Prasad. A [15]

    discussed the general

    behavior of common types of joints in reinforced concrete

    moment resisting frames. The mechanisms involved in joint

    performance with respect to bond and shear transfer are

    critically reviewed and discussed in detail. The factors

    impacting the bond transfer within the joint appears to be

    well related to the level of axial load and the amount of

  • ISSN: 2277-3754

    ISO 9001:2008 Certified International Journal of Engineering and Innovative Technology (IJEIT)

    Volume 2, Issue 10, April 2013

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    transverse reinforcements in the joints. The parameters that

    affect the shear demand and shear strength of the joint are

    explained. The design of shear reinforcement within the

    joint and its detailing aspects are also discussed.

    III. FRAMED JOINTS

    Beam column joints can be critical regions in reinforced

    concrete frames designed for inelastic response to severe

    seismic attack. As a consequence of seismic moments in

    columns of opposite signs immediately above and below

    the joint, the joint region is subjected to horizontal and

    vertical shear forces whose magnitude is typically many

    times higher than in the adjacent beams and columns. If not

    designed for, joint shear failure can result. DESIGN OF JOINTS

    Joint types

    According to geometrical configuration

    Interior, Exterior, Corner

    According to loading conditions and structural behavior

    Type-I, Type-II

    Interior joint:- As shown in Fig..1 An interior joint has

    beams framing into all four sides of the joint. To be

    classified as an interior joint, the beam should cover at least

    ¾ the width of the column, and the total depth of shallowest

    beam should not be less than ¾ the total depth of the

    deepest beam.

    Fig. 1 Interior joint

    Exterior Joint:- As shown in Fig..2 An Exterior joint has

    at least two beams framing into opposite sides of the joint.

    To be classified as an exterior joint, the widths of the beams

    on the two opposite faces of the joint should cover at least

    ¾ the width of the column, and the depths of these two

    beams should not be less than ¾ the total depth of deepest

    beam framing in to the joint.

    Fig. 2 Exterior Joint

    Corner Joint:- As shown in Fig..3 A Corner joint has at

    least one beam framing into the side of the joint. To be

    classified as a corner joint, the widths of the beam on the

    face of the joint should cover at least ¾ the width of the

    column.

    Fig. 3 Corner joint

    Type1- Static loading Strength important, Ductility secondary

    A type-1 joint connects members in an ordinary structure

    designed on the basis of strength, to resist the gravity and

    wind load.

    Type2-Earthquake and blast loading Ductility + strength, inelastic range of deformation, Stress

    reversal

    A type-2 joint connects members designed to have

    sustained strength under deformation reversals into the

    inelastic range, such as members designed for earthquake

    motions, very high wind loads, or blast effects.

    Fig. 4 Typical Beam Column Connections

    Joint loads and resulting forces: As shown in Fig.5 The

    joint region must be designed to resist forces that the beam

    and column transfer to the joint, including axial loads,

    bending moment, torsion, and shear force. Fig.ure3.7 (a)

    shows the joint loads acting on the free body of a typical

    joint of a frame subjected to gravity loads, with moments

    M1 and M2 acting on the opposite sides, in the opposing

    sense.

    Fig. 5 Joint Loads and Resulting Forces from Gravity Forces

    These moments will be unequal, with their difference

    equilibrated by the sum of column moments M3 and M4.

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    Fig.ure 3.7 (b) shows the resulting forces to be transmitted

    through the joint. The joint shear on plane passing through

    the center of the joint is

    Vu = T1 – T2 – V3

    Fig.6 Joint Loads and Resulting Forces from Lateral Forces

    Above Fig.6 (a) shows the loads acing on a joint in a

    structure subjected to sideway loading. Fig.6 (b) shows the

    resulting internal forces. Only for heavy lateral loading,

    such as from seismic forces, would the moments acting on

    opposite faces of the joint acting in the same sense,

    producing very high horizontal shear within the joint. The joint shear on plane passing through the center of the joint

    is

    Vu = T1 + C2 – V3

    Vu = T1 + T2 – V3 (C2 = T2)

    Joint confinement:-

    bb,x ≥ 0.75 bc,x

    bb,y ≥ 0.75 bc,y

    bb,y ≥ 0.75 bc,y

    Fig. 7 Plan View of Interior Joint with Beams in X and Y

    Direction Providing Confinement

    Fig. 8 Plan View of Exterior Joint with Beams in X and Y

    Direction Providing Confinement

    IV. LOADING SYSTEMS

    The structures are being imposed by many loads e.g.

    dead load, live load, imposed(wind) load, snow load,

    earthquake load etc. The structures have to be designed in

    such a way that they can bear these loads to overcome the

    collapse or failure of the structures. Today the earthquake

    resistant structures are being designed more widely. To

    understand the behavior of the structures in the earthquake,

    the researchers are applying cyclic loading to the building

    in the laboratory.

    Types of Loading systems:- The behavior of building is studied with different types of

    loads. 1) Static loading: - Static means slow loading in structural

    testing. Test of components:-Beams(bending),column

    (axial),beams and columns

    Purpose of testing:- Determine strength limits Determine the flexibility/rigidity of structures 2) Quasi-static loading:- Very slowly applied loading in

    one direction (monotonic)

    3) Quasi-static reversed cyclic loading:-Very slowly

    applied loading in both direction (cyclic)

    4) Dynamic (random) loading:- Shake at the base or any

    other elevation of the structure shaking similar to that

    during earthquakes.

    Monotonic Loading

    The Monotonic loading can be defined as very slowly

    applied loading in one direction it may be in upward or

    downward direction. In Monotonic loading for the failure of

    the member the load is maximum . Therefore, the structures

    must be designed for monotonic loading. If the structures

    are designed as per monotonic loading, the structures are

    safe in other loading systems.

    Fig. 9 Bond Slips Relationship of Deformed Bars

  • ISSN: 2277-3754

    ISO 9001:2008 Certified International Journal of Engineering and Innovative Technology (IJEIT)

    Volume 2, Issue 10, April 2013

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    V. FINITE ELEMENT ANALYSIS

    The Finite Element Analysis is a numerical technique in

    which all complexities of the problems varying shape,

    boundary conditions and loads are maintained as they are

    but the solutions obtained are approximate. Solutions can

    be obtained for all problems by Finite Element

    Analysis.Various steps involved in FEM are as follows. 1. Selection of field variables and the elements.

    2. Discretization of structure.

    3. Finding the element properties

    4. Assembling element stiffness matrix

    5. Solution of nodal unknown

    FINITE ELEMENT MODELING & ANALYSIS

    Ansys software has been used for conducting the finite

    element analysis of the Concrete Beam Column Joint.

    Ansys has many features which help to carry out detailed

    study for such kind of complex problems.

    ELEMENT TYPE USED : As shown in Fig.10

    Reinforced Concrete An eight-node solid element, Solid65,

    was used to model the concrete. The solid element has eight

    nodes with three degrees of freedom at each node –

    translations in the nodal x, y, and z directions. The element

    is capable of plastic deformation, cracking in three

    orthogonal directions, and crushing. The geometry and

    node locations for this element type are shown in below.

    Fig.10 Solid65 – 3-D Reinforced Concrete Solid (ANSYS 1998)

    A Link8 element is used to model the steel reinforcement.

    Two nodes are required for this element. Each node has

    three degrees of freedom, – translations in the nodal x, y,

    and z directions. The element is also capable of plastic

    deformation. The geometry and node locations for this

    element type are shown in Fig.ure below.

    MATERIAL PROPERTIES: Concrete: - As shown in Fig.11Development of a model for the behavior of concrete

    is a challenging task. Concrete is a quasi-brittle material

    and has different behavior in compression and tension. The

    tensile strength of concrete is typically 8-15% of the

    compressive strength (Shah, et al. 1995). Fig.ure below

    shows a typical stress-strain curve for normal weight

    concrete (Bangash 1989).

    Fig.11 Typical Uniaxial Compressive and Tensile Stress-Strain

    Curve For concrete (Bangash 1989)

    In compression, the stress-strain curve for concrete is

    linearly elastic up to about 30 percent of the maximum

    compressive strength. Above this point, the stress increases

    gradually up to the maximum compressive strength. After it

    reaches the maximum compressive strength σcu

    , the curve

    descends into a softening region, and eventually crushing

    failure occurs at an ultimate strain εcu

    . In tension, the stress-

    strain curve for concrete is approximately linearly elastic up

    to the maximum tensile strength. After this point, the

    concrete cracks and the strength decreases gradually to zero

    (Bangash 1989). Steel Reinforced Concrete [Smeared

    Model] Material Properties:- In this project the structure

    has been modeled using Steel Reinforced Concrete. The

    material properties mentioned below act equivalent for a

    Smeared Reinforcement concrete model using solid 65

    elements in Ansys. Many research papers have been

    published using similar kind of model. Broujerdian et. al

    (2010) have worked using a similar approach. The used of

    these features enables obtaining good results with fewer solvers and modeling time.

    VI. PROBLEM STATEMENT

    Problem Definition

    • A ground plus five Storey RC office building is considered.

    • Plan dimensions :12 m x 12 m • Location considered: Zone-III • Soil Type considered: Rock Soil

    General Data of Building:

    • Grade of concrete : M 20 • Grade of steel considered : Fe 250, Fe 415 • Live load on roof: 2 KN/m2 (Nil for earthquake) • Live load on floors : 4 KN/m2 • Roof finish : 1.0 KN/m2 • Floor finish : 1.0 KN/m2 • Brick wall in longitudinal direction : 250 mm

    thick

    • Brick wall in transverse direction : 150 mm thick

    • Beam in longitudinal direction : 230X300 mm • Beam in transverse direction : 230X300 mm • Column size : 300X600 mm • Density of concrete : 25 KN/m3

  • ISSN: 2277-3754

    ISO 9001:2008 Certified International Journal of Engineering and Innovative Technology (IJEIT)

    Volume 2, Issue 10, April 2013

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    • Density of brick wall including plaster : 20 KN/m

    3

    • Plinth beam(PB1) : 350X250 mm • Plinth beam(PB2) : 250X300 mm Analysis:-

    1) Ansys Software

    ( Non-Linear finite element

    Analysis) :

    The exterior and corner beam-column joint to be

    Analyzed in the Ansys FEM Software.

    Fig.12 Dimensional View Showing Exterior and Corner Beam-

    Column Joint

    2) Ansys Analysis: From As shown in Fig. 13 Once the reinforcement detailing of the beam and

    column is known the exterior beam-column joint is

    modeled in Ansys FEM Software. Non-linear analysis of

    exterior and corner joint is carried out with 6 load step and

    30 iterations in each load step. The mesh size of 80 mm is

    taken for macro-elements in concrete part of the beam and

    column. The exterior beam-column joint is modeled and a

    monotonic loading of 5 KN is applied at the tip of the beam

    till the failure of the beam takes place. The application of

    the monotonic loading is shown in Fig 13. The behavior of

    this joint is studied with different parameters.

    Fig. 13 Application of the Monotonic loading to exterior joint

    VII.FINITE ELEMENT MODELLING AND ANALYSIS OF BEAM-COLUMN JOINTS

    As shown in Fig. 14 the exterior and corner beam-

    column joint is considered to study joint behavior subjected

    to monotonic loading. Preparation of FE model is carried

    out based on results obtained from space frame analysis of

    a building located in zone-III. Model construction is done

    by defining geometrical joints and lines. Material definition

    is carried out prior to assigning of macro elements. The

    joint is fully restrained at the column ends. The load is

    applied at the tip of the beam in one direction.

    Fig. 14 Test Specimen Arrangement

    Modeling Arrangement:-The test specimen arrangement

    is shown in Fig.14 the mesh was generated using a

    preprocessor. The corner of the macro elements were user-

    defined and then filled by automatic mesh generation.

    These were arranged to keep the mesh as regular as

    possible, with a maximum element aspect ratio of 2.The

    loading and boundary constraints were then applied to the

    macro element nodes as shown in Fig. 15

    Fig. 15 General model layout showing boundary conditions

    Reinforcing bar anchorage:-To study the effect of

    reinforcing bars on joint behavior, smeared bars were

    specified for all of the reinforcement within the model. The

    anchorage of the beam tension bar is one of the main

    contributors to joint behavior. The anchorage behavior is

    significantly affected by the material model of the element

    in which the bar is embedded, and more importantly, any

    additional reinforcing bars within the element. Boundary

    conditions:- As shown in Fig..15 Modeling of the boundary

    conditions is often the most critical aspect in achieving

    sensible, reliable data from a finite element model. In the

    test specimens, the critical zones (around the joint) were far

    from the applied boundary constraints (edge of the

    model).Accurate boundary constraints however, still

    required. The column connections were modeled as hinged

    supports attached to a single node to allow full rotation.

    Column end caps, used to support and restrain the test

    specimens in the loading frame, were included in the model

    to allow the effective length of the column to be modeled

    correctly. The material for the end caps had a higher

    ultimate capacity, but had a similar stiffness to the concrete

    to reduce restraint in the adjacent elements. Mesh

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    Volume 2, Issue 10, April 2013

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    arrangement:- A single mesh arrangement was developed

    for use with the bent down bar anchorage.

    Fig.16 modeling of corner beam column joints in the Ansys.

    Fig.17 Modeling of Exterior beam column joints in the Ansys

    VIII. RESULTS AND DISCUSSIONS

    Parametric Study:-The exterior and corner beam-column

    joints are studied with different parameters like i.e.

    Maximum principle stress, Minimum principle stress,

    Displacement, Deformation also studied end conditions of

    beam column joint i.e. fixed end conditions, Hinge end

    conditions and Stiffness variation of beam column joint i.e.

    Corner and Exterior joint subjected to monotonic loading.

    Fig. 18 Case No.(1) Corner Beam-column Joint.

    Fig.19 Case No.(2) Exterior Beam-column Joint.

    1. Corner beam column joint (Hinge Condition) the

    dimensions are provided as below.

    Beam size 230mm X 300mm

    Column size 230mm X 600mm

    Table I

    Load

    in KN

    Displacement in

    mm

    Mini. Stress

    in N/mm2

    Maxi.

    Stress

    in N/mm2

    5 0.613871 -0.403609 0.34717

    10 1.75262 -7.09 4.14598

    15 1.9085 -7.46933 4.58003

    20 2.0533 -9.14242 7.79495

    25 2.30366 -9.87 7.87493

    30 2.59696 -14.9082 9.97489

    Fig.20 Load Vs Maximum Deformation, Minimum Stress,

    Maximum Stress Graph

    2. Exterior beam column joint (Hinge conditions) the

    dimensions are provided as below.

    Beam 230 mm x 300 mm

    Column 230 mm x 600 mm

  • ISSN: 2277-3754

    ISO 9001:2008 Certified International Journal of Engineering and Innovative Technology (IJEIT)

    Volume 2, Issue 10, April 2013

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    Table II

    Load

    in kN

    Displacement

    (mm)

    Mini. Stress

    N/mm2

    Maxi. Stress

    in N/mm2

    5 0.792331 -0.88596 0.432535

    10 1.92308 -4.77346 5.60122

    15 2.1009 -6.77345 5.62132

    20 2.19251 -11.7367 10.6008

    25 2.38355 -14.8968 14.405

    30 2.55905 -17.9068 17.6008

    Fig.21 Load Vs Maximumdeformation, Minimum Stress,

    Maximum Stress Graph

    3. Fixed support conditions for corner beam column joint

    the dimensions are provided as below.

    Beam 230 mm x 300 mm

    Column 230 mm x 600 mm

    Table III

    Load in

    KN

    Displacement

    in mm

    Mini. Stress in

    N/mm2

    Maxi. Stress

    in N/mm2

    5 2.72677 -1.00969 6.27466

    10 2.8003 -2.47423 7.03936

    15 2.88495 -3.791 8.19089

    20 2.9633 -4.793 8.89089

    25 3.2035 -5.4371 9.5062

    30 3.6075 -7.951 14.9088

    Fig.22 Load Vs Maximum Deformation, Minimum Stress,

    Maximum Stress Graph

    4. Fixed support conditions for Exterior beam column joint

    the dimensions are provided as below.

    Beam 230mmx 300mm

    Column 230mmx 600mm

    Table IV

    Load in

    KN

    Displacement

    in mm

    Mini. Stress

    in N/mm2

    Maxi. Stress

    in N/mm2

    5 0.499 -1.7309 1.53771

    10 1.205 -1.9875 2.47114

    15 1.558 -4.04003 2.69536

    20 1.832 -4.90289 4.74555

    25 2.157 -5.4525 5.6299

    30 2.308 -9.1298 7.47541

    Fig.23 Load Vs Maximum Deformation, Minimum Stress,

    Maximum Stress Graph

    5.Corner beam column joint with varying stiffness the

    dimensions are provided as below.

    Case NO 1 Beam 230mm X 375mm

    Column 230mm X 600mm

    Stiffness of beam: KB = 252685.54 mm3

    Stiffness of Column: Kc =1380000 mm3

    Stiffness of Joint: Kj = KB/ Kc

    = 252685.54 / 1380000

    = 0.18

    Table V

    Load in

    KN

    Displacement in

    mm

    Mini. Stress

    in N/mm2

    Maxi. Stress

    in N/mm2

    5 0.4172 -0.931495 0.303477

    10 0.8344 -3.92411 2.20581

    15 1.6689 -4.00092 2.22582

    20 3.3478 -6.00393 3.77446

    25 3.6889 -6.94422 4.6321

    30 3.983 -7.60862 6.17119

    Fig.24 Load Vs Maximum Deformation, Minimum Stress,

    Maximum Stress Graph

    6. Exterior beam column joint with varying stiffness the

    dimensions are provided as below.

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    Volume 2, Issue 10, April 2013

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    Case NO 1 Beam 230mm X 450mm

    Column 230mm X 375mm

    Stiffness of beam: KB = 436640.62 mm3

    Stiffness of Column: Kc = 336914.06 mm3

    Stiffness of Joint: Kj = KB/ Kc

    = 436640.62/336914.06

    = 1.29

    Fig. 25 Load Vs Maximum Deformation, Minimum Stress,

    Maximum Stress Graph

    7. Variation in stiffness of corner beam column joint

    Table VII

    Load

    in

    KN

    Displace

    ment in

    mm

    Displace

    ment in

    mm

    Displacem

    ent in mm

    Displaceme

    nt in mm

    Sj=0.18 Sj=1.29 Sj=2.05 Sj=0.75

    5 0.4172 0.34116 0.274849 0.5875

    10 0.8344 0.68233 0.549698 1.175

    15 1.6689 1.36467 1.099396 1.3512

    20 3.3478 2.7293 1.319256 1.6215

    25 3.6889 3.4095 1.649056 2.0268

    30 3.983 4.4295 2.141056 2.6346

    Fig. 26 Load Vs Maximum Deformation

    8. Variation in stiffness of corner beam column joint

    Table VIII

    Load

    in KN

    Mini.

    Stress in

    N/mm2

    Mini.

    Stress in

    N/mm2

    Mini.

    Stress

    In N/mm2

    Mini.

    Stress

    In N/mm2

    Sj=0.18 Sj=1.29 Sj=2.05 Sj=0.75

    5 -0.931495 -0.889535 -0.922823 -0.035402

    10 -3.92411 -1.21114 -1.33809 -0.88506

    15 -4.00092 -2.12256 -1.53242 -1.77012

    20 -6.00393 -2.13257 -1.56506 -2.27215

    25 -6.94422 -2.33399 -1.66497 -2.30116

    30 -7.60862 -2.34361 -1.8868 -3.2847

    Fig. 27 Load Vs Minimum Stress Graph

    9. Variation in stiffness of corner beam column joint

    Table IX

    Load

    in KN

    Maxi.

    Stress

    in N/mm2

    Maxi.

    Stress

    in N/mm2

    Maxi.

    Stress

    in N/mm2

    Maxi.

    Stress in

    N/mm2

    Sj=0.18 Sj=1.29 Sj=2.05 Sj=0.75

    5 0.303477 0.3956 0.389974 0.008042

    10 2.20581 1.66923 0.585308 0.201056

    15 2.22582 1.67924 1.15246 0.402113

    20 3.77446 1.96634 1.20463 1.21377

    25 4.6321 2.93769 1.29138 1.23761

    30 6.17119 6.50058 2.3821 4.01801

    Fig. 28 Load Vs Maximum Stress Graph

    10. Variation in stiffness of Exterior beam column joint:-

    Table X

    Loa

    d in

    KN

    Displacem

    ent in mm

    Displacem

    ent in mm

    Displacem

    ent

    in mm

    Displace

    ment in

    mm

    Sj=1.29 Sj=2.05 Sj=0.75 Sj=0.18

    5 0.604115 0.60052 0.213883 0.507809

    10 1.20823 1.20104 0.427767 1.0156

    15 2.41646 1.38119 0.641712 1.16794

    20 2.8996 1.6571 1.81128 1.40134

    25 3.6244 2.0714 2.12017 1.75134

    30 3.9248 2.6927 2.60442 2.27664

  • ISSN: 2277-3754

    ISO 9001:2008 Certified International Journal of Engineering and Innovative Technology (IJEIT)

    Volume 2, Issue 10, April 2013

    157

    Fig. 29load Vs Displacement Graph

    11. .Variation in stiffness of Exterior beam column joint:-

    Table XI

    Load

    in

    KN

    Mini. Stress

    in N/mm2

    Mini.

    Stress in

    N/mm2

    Mini.

    Stress in

    N/mm2

    Mini.

    Stress in

    N/mm2

    Sj=1.29 Sj=2.05 Sj=0.75 Sj=0.18

    5 -0.858169 -2.09364 -0.429264 -0.88953

    10 -1.71634 -3.06832 -0.858527 -2.25308

    15 -2.33399 -4.05034 -1.397001 -2.68991

    20 -2.60959 -4.899265 -1.57095 -2.88285

    25 -2.97925 -5.79853 -2.13031 -3.91109

    30 -5.54457 -6.09465 -2.83467 -4.5792

    Fig.30 Load Vs Minimum Stress Graph

    12. Variation in stiffness of Exterior beam column joint:-

    Table XII

    Load

    in

    KN

    Maxi.

    Stress in

    N/mm2

    Maxi.

    Stress in

    N/mm2

    Maxi.

    Stress

    in N/mm2

    Maxi.

    Stress

    in N/mm2

    Sj=1.29 Sj=2.05 Sj=0.75 Sj=0.18

    5 1.5166 0.67842 1.3244 2.18446

    10 3.0332 3.00113 2.64879 3.8436

    15 4.543 3.2643 3.55204 4.4024

    20 6.5429 3.50445 7.08526 6.82696

    25 8.0439 4.00889 8.40464 7.9676

    30 10.0439 4.678425 9.2199 9.9624

    Fig. 31 Load Vs Maximum Stress Graph

    IX. CONCLUSION

    1) As load increases displacement, minimum stress and

    maximum stress also increases.

    2) For fixed support condition for corner and exterior joint

    the displacement, minimum stress and maximum stress

    values are minimum as compare to hinge support condition.

    3) The behavior of corner beam column joint is different

    than that of the exterior beam column joint.

    4) For stiffness variation of corner joint for Sj=0.18 the

    displacement is minimum as compare to Sj=1.29, Sj=2.05,

    Sj=0.75.

    5) For stiffness variation of corner joint for Sj=0.18 the

    minimum stress is more as compare to Sj=1.29 and

    Sj=2.05, for Sj=0.75 the minimum stress is maximum as

    compare to Sj=0.18.

    6) For stiffness variation of corner joint for Sj=0.18 the

    maximum stress is more as compare to Sj=1.29 and

    Sj=2.05, for Sj=0.75 the maximum stress is maximum as

    compare to Sj=0.18.

    7) For stiffness variation of Exterior joint for Sj=1.29 the

    displacement is minimum as compare to Sj=2.05, for

    Sj=0.75 and for Sj=0.18 the displacement is maximum as

    compare to Sj=1.29.

    8) For stiffness variation of Exterior joint for Sj=1.29 the

    minimum stress is more as compare to Sj=2.05 and

    Sj=0.75, for Sj=0.18 the minimum stress is more as

    compare to Sj=1.29.

    9) For stiffness variation of Exterior joint for Sj=1.29 the

    maximum stress is less as compare to Sj=2.05.for

    remaining stiffness Sj=0.75 and Sj=0.18 the maximum

    stress is less. (Minimum)

    10) As stiffness of the structure changes the displacement,

    minimum stress and maximum stress changes Non-linearly.

    REFERENCES

    [1] Vladimir Guilherma Haach, Ana Lucia Home De Cresce El Debs and Mounir Khalil El Debs “Evaluation of the

    influence of the column axial load on the behavior of

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    through Numerical simulations “Engineering Structures pp

    965-975. (2008).

    [2] A. El-Nabawy Atta, S. El-Din Fahmy Taher, A.-H. A. Khalil and S. El-Din El-Metwally “Behavior of reinforced high-

    strength concrete beam-column joint.Part1: experimental

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    [3] Baglin Paul S. and Scott Richard H. (November-December) “Finite Element Modeling of Reinforced Concrete Beam-

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    [4] Bakir P.G. and Boduroglu H.M “A new design equation for predicting the joint shear strength of monotonically loaded

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    pp. 1105–1117. (March 2002).

  • ISSN: 2277-3754

    ISO 9001:2008 Certified International Journal of Engineering and Innovative Technology (IJEIT)

    Volume 2, Issue 10, April 2013

    158

    [5] Bing Li, Yiming Wu, and Tso-Chien Pan (January-February) “Seismic Behavior of Nonseismically” Detailed Interior

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    1. (2003)

    [6] Cervenka.V,Cervenka J and Jendele L “Bond infinite element modeling of reinforced concrete” Computational Modeling of

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    [9] Hegger Josef, Sherif Alaa and Roeser Wolfgang “Nonlinear Finite Element Analysis of Reinforced Concrete Beam-

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    (Sept-Oct. 2004)

    [10] Hitoshi Shiohara “A New Model for Joint Shear Failure of Reinforced Concrete Interior Beam to Column Joint” Journal

    of the School of Engineering, The University of Tokyo pp1-

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    [11] Hwang Shyh-Jiann, Lee Hung-Jen, Liao Ti-Fa, Wang Kuo-Chou, and Tsai Hsin-Hung “Role of Hoops on Shear Strength

    of Reinforced Concrete Beam-Column Joints” ACI Structural

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    [12] H. G. Kwak and F. C. Filippou “Nonlinear FE Analysis of R/C Structures under Monotonic Loads” Computers and

    Structures pp 1-16., (1997)

    [13] Murty. C. V. R, Durgesh C. Rai, Bajpai. K. K, and Sudhir K. Jain “Effectiveness of Reinforcement Details in Exterior

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    Resistance” ACI Structural Journal, V. 100, No. 2. (March-

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    [14] Uma. S. R and Meher Prasad. A “Seismic Behavior of Beam Column Joints in Reinforced Concrete Moment Resisting

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    [15] “Earthquake Resistant Design of structures” by Manish Shrikhande and Pankaj Aggarwal.

    AUTHOR BIOGRAPHY

    Prof. Patil S .S.. B.E. (Civil), M.E. (Civil - Structures) , Phd. ISSE( LM ) Is the professor & Head of civil/Structural Engineering Dept.

    WIT Solapur.( M.S.) INDIA

    Mr. Manekari S.S.

    B.E. (Civil), M.E. (Civil - Structures), ISSE (LM) M .E. Student of WIT Solapur.( M.S.) INDIA


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