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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
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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
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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
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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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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
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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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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
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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
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[2] A. El-Nabawy Atta, S. El-Din Fahmy Taher, A.-H. A. Khalil and S. El-Din El-Metwally “Behavior of reinforced high-
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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
158
[5] Bing Li, Yiming Wu, and Tso-Chien Pan (January-February) “Seismic Behavior of Nonseismically” Detailed Interior
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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