Masonry infill is considered as a non-structural element in all type of buildings where masonry use.
But, masonry infill walls are mainly used to increase initial stiffness and strength of reinforced concrete (RC)
frame buildings. This Open First storey is also termed as “Soft Storey”. The upper storeys have brick infilled
wall panels with various opening percentage in it. In many cities of India, it is very common to leave the first
storey of masonry infilled reinforcement concrete (RC) frame building open preliminary to generate parking
space or any other usage in the first storey. Such buildings are highly undesirable in seismically active areas. In
the present study, it is an attempt to access the performance of masonry infilled reinforced concrete (RC) frames
with soft storey of with and without opening. In this paper, symmetrical frame of college building (G+5) located
in seismic zone-III is considered by modelling of initial frame. According to FEMA-273, & ATC-40 which
contain the provisions of calculation of stiffness of infilled frames by modelling infill as“Equivalent Diagonal
Strut Method”. Therefore, the infill panels are modelled as equivalent diagonal strut method. The error
involved in modelling such buildings as neglecting the presence of infills in the upper storeys, is brought out
through the study of an example building with different analytical models. This linear static analysis is to be
carried out on the models such as Strut frame with 15%, 20%, & 25% centre &corner opening, which is
performed by using computer software STAAD-Pro from which different parameters are computed. In which it
shows that how infill panels increase the stiffness of the structure. While the increase in the opening percentage
leads to a decrease on the lateral stiffness of infilled frame. This paper highlights the importance of the presence
of the open first storey in the analysis of the building
MODELLING OF AN INFILL WALL FOR THE ANALYSIS OF A BUILDING FRAME SUBJECTED TO...IAEME Publication
In general the analysis of a building frame is carried out with a bare frame but the presence of masonry infill in a framed structure results in high stiffness and influence the distribution of lateral load and also the response of the framed buildings. It can be noted that there is a large variation of mechanical properties of bricks. Masonry, a combination of brick and mortar, behaves in a highly nonlinear manner. The infill panel needs to be modelled in the analysis of a structural frame subjected to lateral load to obtain its true behaviour. In order to model the masonry infill, its properties required. In order to determine the properties of brick masonry compression tests were conducted on masonry infill panels and prisms.
Seismic evaluation of rc frame with brick masonry infill wallseSAT Journals
Abstract
Infill panels are widely used as partition walls as well as external walls of the building to fill the gap between RC frames. Non-structural member may provide considerable stiffness to the building and hence may improve the performance of the RC building during ground motions. But In most of the cases, the ignorance of this property of masonry in designing of the RC frame may get an unsafe design. There are two methods are used to determine the effect of ground motion. The effect of ground motion on RC frame building has been carried out by considering with and without the stiffness of infill wall. A comparative study is carried out with RC building using Equivalent Lateral Force method and Response Spectrum method. The masonry infill has been modeled as an equivalent diagonal strut element using Hendry formula. Pushover analysis is carried out on bare frame and frame with infill wall. The model has been generated using STAAD Pro and results obtained from the analysis are compared in terms of strength and stiffness with bare frame.
Keywords: Seismic evaluation, Response Spectrum, masonry infill, diagonal strut.
Influence of Modeling Masonry Infill on Seismic Performance of Multi-Storeyed...ijsrd.com
Masonry infilled RC frames are the most common type of structures used for multi-storeyed constructions in the developing countries, even in those which are located in seismically active regions also. Masonry infill walls are mainly used to increase the stiffness and strength of R C framed buildings. R C framed building with open first storey is known as soft storey, which performs poorly during earthquakes. A similar soft storey effect can also appear top storey level if it is used as service storey. The soft storey located in the upper part of the multistorey building does not significantly affect. To observe the effect of masonry infill panel, it is modeled as an equivalent double diagonal strut. In this study 7 models are taken were analyzed with two different techniques of modelling of masonry infill wall with L type of shear wall when subjected to earthquake loading. The results of masonry infill show more stiffness than the strut modeling technique. It is observed that, providing infill wall and shear wall improves earthquake resistant behavior of the structure and also the effect of water pressure, an attempt is made to develop relationship between strength and stiffness ratios for linear trend line.
Effect of infill walls on the seismic performance of the multistoried buildingseSAT Journals
Abstract The most commonly used structural system in our country for almost all types of building are multi-storey reinforced concrete frames with masonry infills. Therefore it is essential to understand the seismic behaviour of these structures when subjected to lateral forces. Several research works has been done on the masonry infilled reinforced concrete frames in the past decades. Mortar is used as a binder in normal brick construction in order to create continuous structural form and to bind together the individual units in brickwork. In the present study, analysis has been carried out by considering the increase in height of building from five to ten storied by using finite element software ANSYS 14.5. The seismic analysis of multi-storeyed building frames with infill walls and without infill walls are conducted. 3D analysis will give more realistic values of deflection and stresses. Since this type of study is not feasible in terms of analysis time taken, 2D model was adopted for the present study. A three bay two dimensional building frame is considered with the number of stories varying from 5 storied to 10 storied. The loading applied is as per IS 1893 (Part I): 2002. Equivalent diagonal strut method is adopted for modelling infill walls. The results showed that there is considerable decrease in deflection when infills are used in RC frames. Key Words: Deflection , Equivalent diagonal strut method, lateral load, Solid brick infills, Storey drift
Analysis of rc frame with and without masonry infill wall with different stif...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
MODELLING OF AN INFILL WALL FOR THE ANALYSIS OF A BUILDING FRAME SUBJECTED TO...IAEME Publication
In general the analysis of a building frame is carried out with a bare frame but the presence of masonry infill in a framed structure results in high stiffness and influence the distribution of lateral load and also the response of the framed buildings. It can be noted that there is a large variation of mechanical properties of bricks. Masonry, a combination of brick and mortar, behaves in a highly nonlinear manner. The infill panel needs to be modelled in the analysis of a structural frame subjected to lateral load to obtain its true behaviour. In order to model the masonry infill, its properties required. In order to determine the properties of brick masonry compression tests were conducted on masonry infill panels and prisms.
Seismic evaluation of rc frame with brick masonry infill wallseSAT Journals
Abstract
Infill panels are widely used as partition walls as well as external walls of the building to fill the gap between RC frames. Non-structural member may provide considerable stiffness to the building and hence may improve the performance of the RC building during ground motions. But In most of the cases, the ignorance of this property of masonry in designing of the RC frame may get an unsafe design. There are two methods are used to determine the effect of ground motion. The effect of ground motion on RC frame building has been carried out by considering with and without the stiffness of infill wall. A comparative study is carried out with RC building using Equivalent Lateral Force method and Response Spectrum method. The masonry infill has been modeled as an equivalent diagonal strut element using Hendry formula. Pushover analysis is carried out on bare frame and frame with infill wall. The model has been generated using STAAD Pro and results obtained from the analysis are compared in terms of strength and stiffness with bare frame.
Keywords: Seismic evaluation, Response Spectrum, masonry infill, diagonal strut.
Influence of Modeling Masonry Infill on Seismic Performance of Multi-Storeyed...ijsrd.com
Masonry infilled RC frames are the most common type of structures used for multi-storeyed constructions in the developing countries, even in those which are located in seismically active regions also. Masonry infill walls are mainly used to increase the stiffness and strength of R C framed buildings. R C framed building with open first storey is known as soft storey, which performs poorly during earthquakes. A similar soft storey effect can also appear top storey level if it is used as service storey. The soft storey located in the upper part of the multistorey building does not significantly affect. To observe the effect of masonry infill panel, it is modeled as an equivalent double diagonal strut. In this study 7 models are taken were analyzed with two different techniques of modelling of masonry infill wall with L type of shear wall when subjected to earthquake loading. The results of masonry infill show more stiffness than the strut modeling technique. It is observed that, providing infill wall and shear wall improves earthquake resistant behavior of the structure and also the effect of water pressure, an attempt is made to develop relationship between strength and stiffness ratios for linear trend line.
Effect of infill walls on the seismic performance of the multistoried buildingseSAT Journals
Abstract The most commonly used structural system in our country for almost all types of building are multi-storey reinforced concrete frames with masonry infills. Therefore it is essential to understand the seismic behaviour of these structures when subjected to lateral forces. Several research works has been done on the masonry infilled reinforced concrete frames in the past decades. Mortar is used as a binder in normal brick construction in order to create continuous structural form and to bind together the individual units in brickwork. In the present study, analysis has been carried out by considering the increase in height of building from five to ten storied by using finite element software ANSYS 14.5. The seismic analysis of multi-storeyed building frames with infill walls and without infill walls are conducted. 3D analysis will give more realistic values of deflection and stresses. Since this type of study is not feasible in terms of analysis time taken, 2D model was adopted for the present study. A three bay two dimensional building frame is considered with the number of stories varying from 5 storied to 10 storied. The loading applied is as per IS 1893 (Part I): 2002. Equivalent diagonal strut method is adopted for modelling infill walls. The results showed that there is considerable decrease in deflection when infills are used in RC frames. Key Words: Deflection , Equivalent diagonal strut method, lateral load, Solid brick infills, Storey drift
Analysis of rc frame with and without masonry infill wall with different stif...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
EXPERIMENTAL MODELING OF IN FILLED RC FRAMES WITH OPENINGIAEME Publication
Reinforced concrete frames are usually infilled with masonry walls but, in most designs, both the shear strength capacity of these walls and the contribution of the infill panel openings on the shear strength of the infilled frame, especially in critical cases of seismic loading are generally ignored. This paper reports the results of an experimental study of the influence of central openings in the infill on the sway stiffness of reinforced concrete plane frames. A series of 1:4 scaled structural models with opening ratios from 0 to 50 percent in steps of 10 percent were designed, constructed and tested in the study to obtain the load - displacement profiles.
Analysis of rc framed structures with central and partial openings in masonry...eSAT Journals
Abstract In Reinforced concrete frames the masonry infill walls are a common practice in countries like India, where the region is prone to seismic activity. In general, the masonry infill walls are treated as nonstructural element in structural analysis and only the contribution of its mass for is considered and it’s structural parameters like strength and stiffness is generally ignored in practice, such an approach may lead to an unsafe design. Infill walls resist lateral loads but because of the openings in the infill wall the resistance may slightly reduce. The IS code provisions do not provide guidelines for the analysis and design of RC frames with infill wall and for different percentage of openings. In this study, an office or residential building outer side central opening or outer side partial openings are used and analysis is carried for Bare Frame model, infill walls without opening, infill walls with outer periphery central opening and infill wall with outer periphery partial opening models. In ETABS software G+14 RC framed building models has been prepared, Equivalent Static Lateral force method, Response spectrum method has been performed for analysis as per IS 1893 : 2002 including p-delta effects. Storey displacement, Storey shear, Storey drift, with soft storey considering the effects of infill wall with central and partial openings are the parameters considered in this study. For modeling, the Equivalent diagonal strut method has been used to find out the width of Strut using FEMA 273 .The results for bare frame, infill wall, and infill wall with central and partial openings are discussed and conclusions are made. Keywords: Equivalent diagonal strut, stiffness, Drift limitation
Behaviour of 3 d rc frames with masonry infill under earthquake loads an ana...eSAT Journals
Abstract Moderate and astringent earthquakes have struck different places in the world, causing rigorous damage to reinforced concrete
structures. The bond between the structural elements and masonry in-fills of the building is habitually effected by Earthquake. The
voids between horizontal and vertical resisting elements of the building frame is filled by Masonry in-fills. An infill wall enhances
considerably the strength and rigidity of the structure. It has apperceived that frames with in-fills have more vigor and rigidity
compared to the bare frames Hence this study is about the demeanor of 3D-RC frames with and without masonry in-fills utilizing
E-TABS. parameters were studied like displacement, lateral load distribution, stiffness and overturning moment of the frames and
it is concluded that, the in-fill walls are needed to be considered while designing phase of the structures.
Keywords: Earthquake load, 3D RC Frame, Masonry In-Fill
Seismic Vulnerability Assessment of Steel Moment Resisting Frame due to Infil...IDES Editor
Steel moment resisting frame with open first storey
(soft storey) is known to perform well compared with the RC
frames during strong earthquake shaking. The presence of
masonry infill wall influences the overall behavior of the
structure when subjected to lateral forces, when masonry infill
are considered to interact with their surrounding frames the
lateral stiffness and lateral load carrying capacity of structure
largely increase. In this paper, the seismic vulnerability of
building with soft storey is shown with an example of G+10
three dimensional (3D) steel frame. The open first storey is
an important functional requirement of almost all the urban
multi-storey buildings, and hence, cannot be eliminated.
Hence some special measures need to be adopted for this
specific situation. The under-lying principle of any solution
to this problem is in increasing the stiffness’s of the first
storey such that the first storey stiffness is at least 50% as
stiff as the second storey, i.e., soft first storeys are to be avoided,
and providing adequate lateral strength in the first storey. In
this paper, stiffness balancing is proposed between the first
and second storey of a steel moment resisting frame building
with open first storey and brick infills as described in models.
A simple example building is analyzed by modeling it with
nine different methods. The stiffness effect on the first storey
is demonstrated through the lateral displacement profile of
the building.
Importance of Modeling of Masonry Infill and Effect of Soft Storey on Seismic...ijsrd.com
RC framed high rise buildings are generally designed without considering the structural action of masonry infill walls present. These walls are widely used as partitions and considered as non-structural elements. But they affect both the structural and non-structural performance of the RC buildings during earthquakes. RC framed building with open first storey is known as soft storey, which performs poorly during earthquakes. A similar soft storey effect can also appear, at intermediate storey level if a storey used as a service storey. The soft storey located in the lower part of the high rise building especially the ground storey is undesirable as it attracts severely large seismic forces. At the same time, the soft storey located in the upper part of the high rise building does not significantly affect. To study the effect of masonry infill and its modeling technique with different soft storey level, 6 Models of R C framed building were analyzed with two different techniques of modeling of masonry infill with one type of shear wall when subjected to earthquake loading. Technique one is showing more strength and stiffness than two and an attempt is made to develop relationship between strength and stiffness ratios for linear trend line.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Effect of soft storeys in earthquake resistant analysis of rc framed structureseSAT Journals
storey in which the stiffness is less than 70% of the storey above or less
than 80% of the combined stiffnesses of the three storeys above. It is the general practice in the multistoreyed buildings to
accommodate parking facilities for the vehicles of the occupants of the building. As we know that the soft storey in a building
structure causes stiffness irregularity in a structure, due to this the structure undergoes unequal storey drifts, formation of the
plastic hinges and then finally resulting into the collapse of the structure.This research work purely interacts with the effect of the
soft storeys in the analysis of RC framed structures as entitled above, and in this work the soft storeys positions has been provided
at different levels as shown in the analytical modelling. All the models are analyzed by using the ETABS software. The seismic
analysis performed consists of the Equivalent static analysis (ESA), response spectrum analysis (RSA), and the push over analysis
(PA). The seismic base shear forces, storey drifts, and the displacements has been compared with the three analysis methods as
listed above. With the aid of the push over analysis the values of the ductility and the response reduction factor have been
obtained. Apart from these, the performance point parameters such as spectral acceleration(Sa) , spectral displacement (Sd),
Base shear(V) and the roof displacement(D) has been also illustrated in this work and a detailed information of several stages of
the hinge formation (A,B,IO,LS,CP,C,D,E) has also been illustrated.. Keywords: Soft Storey, Stiffness, Storey Drift, Storey Displacement, Earthquake, RC Frames
NONLINEAR BEHAVIOR AND FRAGILITY ASSESSMENT OF MULTI-STORY CONFINED MASONRY W...IAEME Publication
This paper presents numerical study analysis and the results of confined masonry walls. The studied parameters were number of bays, number of stories, and openings of walls. It was showed that the window opening could reduce the lateral capacity of the solid by ranges of 7-27% for one bay wall, 6-30% for two bay walls, and 11-26% for three bays wall. The door opening could reduce the solid wall capacity by ranges of 11-42% for one bay wall, 13-49% for two bay walls, and 23-44% for three bays wall. This paper presents the most significant contributions in the field of vulnerability assessment. It is shown that methodology is very useful for assessing the seismic vulnerability of confined masonry structures for estimating the cyclic load induced economic losses based on an engineering demand parameter closely related to structural damage.
Lateral Load Analysis of Shear Wall and Concrete Braced Multi-Storeyed R.C Fr...ijsrd.com
Generally RC framed structures are designed without regards to structural action of masonry infill walls present. Masonry infill walls are widely used as partitions. These buildings are generally designed as framed structures without regard to structural action of masonry infill walls. They are considered as non- structural elements. RC frame building with open first storey is known as soft storey, which performs poorly during strong earthquake shaking. Past earthquakes are evident that collapses due to soft storeys are most often in RC buildings. In the soft storey, columns are severely stressed and unable to provide adequate shear resistance during the earthquake. . In this study, 3D analytical model of twelve storeyed buildings have been generated for different buildings Models and analyzed using structural analysis tool 'ETABS'. To study the effect of infill, ground soft, bare frame and models with ground soft having concrete core wall and shear walls and concrete bracings at different positions during earthquake; seismic analysis using both linear static, linear dynamic (response spectrum method) has been performed. The analytical model of the building includes all important components that influence the mass, strength, stiffness and deformability of the structure.
Review on Effective utilization of RCC Shear walls for Design of Soft Storey ...IJERA Editor
Multi-storey buildings in metropolitan cities require open taller first storey for parking of vehicle and/or for retail shopping, large space for meeting room or a banking hall owing to lack of horizontal space and high cost. Due to these functional requirements, the first storey has lesser strength and stiffness as compared to upper stories, which are stiffened by masonry infill walls. Increased flexibility of first storey results in extreme deflections, which in turn, leads to concentration of forces at the second storey connections accompanied by large plastic deformation. In addition, most of the energy developed during the earthquake is dissipated by the column of the soft stories. In this process the plastic hinges are formed at the ends of column, which transform the soft stories into a mechanism. In such cases the collapse is unavoidable. Therefore, the soft stories deserve a special consideration in analysis and design
Behavioural Study of RC Flat Plate Multi-Storey Building Persuaded By Stiffne...IJERA Editor
With a very swift development in urban areas the framed structures which are infilled by brick masonry or
concrete blocks are widely used as partition walls and also exterior walls. Masonry infill walls are common
element in structural system which modifies the conduction of building under the lateral load. These structures
resist the moderate earthquakes and accomplish well in such a prime manner that even if they have no load
bearing function. Evidently, during the time of resolution of such a multi-storey structure, the infilled frame is
considered as bare frame, because IS codes do not provide any guide lines for the analysis and design of RC
frames with infill wall. This paper addresses the numerical study of G+10 RC flat plate framed building with
different cases i.e, soft story at ground level (Basement), with soft story at 5th floor level, without soft storey and
bare frame building by using ETABS as soft computing tool. All these cases are analyzed for equivalent static
method and Response spectrum method. By this, dynamic properties are evaluated and according to the results
obtained conclusions are drawn
Dynamic Analysis of Soft Storey Frame with IsolatorsIJMTST Journal
Soft storey buildings are very common in Indian housing construction and the bottom storey is left open without walls for car parking. Past earthquakes showed that these kinds of buildings performed poor and the damages are also heavy. As the base isolation is a technique developed to prevent or minimize damage to building during an earthquake, this study focuses on the time history analysis of a soft-storey building with and without lead rubber isolator. The soft-storey building with and without isolator is analysed using Elcenrto earthquake data and the dynamic characteristics are compared.
EXPERIMENTAL MODELING OF IN FILLED RC FRAMES WITH OPENINGIAEME Publication
Reinforced concrete frames are usually infilled with masonry walls but, in most designs, both the shear strength capacity of these walls and the contribution of the infill panel openings on the shear strength of the infilled frame, especially in critical cases of seismic loading are generally ignored. This paper reports the results of an experimental study of the influence of central openings in the infill on the sway stiffness of reinforced concrete plane frames. A series of 1:4 scaled structural models with opening ratios from 0 to 50 percent in steps of 10 percent were designed, constructed and tested in the study to obtain the load - displacement profiles.
Analysis of rc framed structures with central and partial openings in masonry...eSAT Journals
Abstract In Reinforced concrete frames the masonry infill walls are a common practice in countries like India, where the region is prone to seismic activity. In general, the masonry infill walls are treated as nonstructural element in structural analysis and only the contribution of its mass for is considered and it’s structural parameters like strength and stiffness is generally ignored in practice, such an approach may lead to an unsafe design. Infill walls resist lateral loads but because of the openings in the infill wall the resistance may slightly reduce. The IS code provisions do not provide guidelines for the analysis and design of RC frames with infill wall and for different percentage of openings. In this study, an office or residential building outer side central opening or outer side partial openings are used and analysis is carried for Bare Frame model, infill walls without opening, infill walls with outer periphery central opening and infill wall with outer periphery partial opening models. In ETABS software G+14 RC framed building models has been prepared, Equivalent Static Lateral force method, Response spectrum method has been performed for analysis as per IS 1893 : 2002 including p-delta effects. Storey displacement, Storey shear, Storey drift, with soft storey considering the effects of infill wall with central and partial openings are the parameters considered in this study. For modeling, the Equivalent diagonal strut method has been used to find out the width of Strut using FEMA 273 .The results for bare frame, infill wall, and infill wall with central and partial openings are discussed and conclusions are made. Keywords: Equivalent diagonal strut, stiffness, Drift limitation
Behaviour of 3 d rc frames with masonry infill under earthquake loads an ana...eSAT Journals
Abstract Moderate and astringent earthquakes have struck different places in the world, causing rigorous damage to reinforced concrete
structures. The bond between the structural elements and masonry in-fills of the building is habitually effected by Earthquake. The
voids between horizontal and vertical resisting elements of the building frame is filled by Masonry in-fills. An infill wall enhances
considerably the strength and rigidity of the structure. It has apperceived that frames with in-fills have more vigor and rigidity
compared to the bare frames Hence this study is about the demeanor of 3D-RC frames with and without masonry in-fills utilizing
E-TABS. parameters were studied like displacement, lateral load distribution, stiffness and overturning moment of the frames and
it is concluded that, the in-fill walls are needed to be considered while designing phase of the structures.
Keywords: Earthquake load, 3D RC Frame, Masonry In-Fill
Seismic Vulnerability Assessment of Steel Moment Resisting Frame due to Infil...IDES Editor
Steel moment resisting frame with open first storey
(soft storey) is known to perform well compared with the RC
frames during strong earthquake shaking. The presence of
masonry infill wall influences the overall behavior of the
structure when subjected to lateral forces, when masonry infill
are considered to interact with their surrounding frames the
lateral stiffness and lateral load carrying capacity of structure
largely increase. In this paper, the seismic vulnerability of
building with soft storey is shown with an example of G+10
three dimensional (3D) steel frame. The open first storey is
an important functional requirement of almost all the urban
multi-storey buildings, and hence, cannot be eliminated.
Hence some special measures need to be adopted for this
specific situation. The under-lying principle of any solution
to this problem is in increasing the stiffness’s of the first
storey such that the first storey stiffness is at least 50% as
stiff as the second storey, i.e., soft first storeys are to be avoided,
and providing adequate lateral strength in the first storey. In
this paper, stiffness balancing is proposed between the first
and second storey of a steel moment resisting frame building
with open first storey and brick infills as described in models.
A simple example building is analyzed by modeling it with
nine different methods. The stiffness effect on the first storey
is demonstrated through the lateral displacement profile of
the building.
Importance of Modeling of Masonry Infill and Effect of Soft Storey on Seismic...ijsrd.com
RC framed high rise buildings are generally designed without considering the structural action of masonry infill walls present. These walls are widely used as partitions and considered as non-structural elements. But they affect both the structural and non-structural performance of the RC buildings during earthquakes. RC framed building with open first storey is known as soft storey, which performs poorly during earthquakes. A similar soft storey effect can also appear, at intermediate storey level if a storey used as a service storey. The soft storey located in the lower part of the high rise building especially the ground storey is undesirable as it attracts severely large seismic forces. At the same time, the soft storey located in the upper part of the high rise building does not significantly affect. To study the effect of masonry infill and its modeling technique with different soft storey level, 6 Models of R C framed building were analyzed with two different techniques of modeling of masonry infill with one type of shear wall when subjected to earthquake loading. Technique one is showing more strength and stiffness than two and an attempt is made to develop relationship between strength and stiffness ratios for linear trend line.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Effect of soft storeys in earthquake resistant analysis of rc framed structureseSAT Journals
storey in which the stiffness is less than 70% of the storey above or less
than 80% of the combined stiffnesses of the three storeys above. It is the general practice in the multistoreyed buildings to
accommodate parking facilities for the vehicles of the occupants of the building. As we know that the soft storey in a building
structure causes stiffness irregularity in a structure, due to this the structure undergoes unequal storey drifts, formation of the
plastic hinges and then finally resulting into the collapse of the structure.This research work purely interacts with the effect of the
soft storeys in the analysis of RC framed structures as entitled above, and in this work the soft storeys positions has been provided
at different levels as shown in the analytical modelling. All the models are analyzed by using the ETABS software. The seismic
analysis performed consists of the Equivalent static analysis (ESA), response spectrum analysis (RSA), and the push over analysis
(PA). The seismic base shear forces, storey drifts, and the displacements has been compared with the three analysis methods as
listed above. With the aid of the push over analysis the values of the ductility and the response reduction factor have been
obtained. Apart from these, the performance point parameters such as spectral acceleration(Sa) , spectral displacement (Sd),
Base shear(V) and the roof displacement(D) has been also illustrated in this work and a detailed information of several stages of
the hinge formation (A,B,IO,LS,CP,C,D,E) has also been illustrated.. Keywords: Soft Storey, Stiffness, Storey Drift, Storey Displacement, Earthquake, RC Frames
NONLINEAR BEHAVIOR AND FRAGILITY ASSESSMENT OF MULTI-STORY CONFINED MASONRY W...IAEME Publication
This paper presents numerical study analysis and the results of confined masonry walls. The studied parameters were number of bays, number of stories, and openings of walls. It was showed that the window opening could reduce the lateral capacity of the solid by ranges of 7-27% for one bay wall, 6-30% for two bay walls, and 11-26% for three bays wall. The door opening could reduce the solid wall capacity by ranges of 11-42% for one bay wall, 13-49% for two bay walls, and 23-44% for three bays wall. This paper presents the most significant contributions in the field of vulnerability assessment. It is shown that methodology is very useful for assessing the seismic vulnerability of confined masonry structures for estimating the cyclic load induced economic losses based on an engineering demand parameter closely related to structural damage.
Lateral Load Analysis of Shear Wall and Concrete Braced Multi-Storeyed R.C Fr...ijsrd.com
Generally RC framed structures are designed without regards to structural action of masonry infill walls present. Masonry infill walls are widely used as partitions. These buildings are generally designed as framed structures without regard to structural action of masonry infill walls. They are considered as non- structural elements. RC frame building with open first storey is known as soft storey, which performs poorly during strong earthquake shaking. Past earthquakes are evident that collapses due to soft storeys are most often in RC buildings. In the soft storey, columns are severely stressed and unable to provide adequate shear resistance during the earthquake. . In this study, 3D analytical model of twelve storeyed buildings have been generated for different buildings Models and analyzed using structural analysis tool 'ETABS'. To study the effect of infill, ground soft, bare frame and models with ground soft having concrete core wall and shear walls and concrete bracings at different positions during earthquake; seismic analysis using both linear static, linear dynamic (response spectrum method) has been performed. The analytical model of the building includes all important components that influence the mass, strength, stiffness and deformability of the structure.
Review on Effective utilization of RCC Shear walls for Design of Soft Storey ...IJERA Editor
Multi-storey buildings in metropolitan cities require open taller first storey for parking of vehicle and/or for retail shopping, large space for meeting room or a banking hall owing to lack of horizontal space and high cost. Due to these functional requirements, the first storey has lesser strength and stiffness as compared to upper stories, which are stiffened by masonry infill walls. Increased flexibility of first storey results in extreme deflections, which in turn, leads to concentration of forces at the second storey connections accompanied by large plastic deformation. In addition, most of the energy developed during the earthquake is dissipated by the column of the soft stories. In this process the plastic hinges are formed at the ends of column, which transform the soft stories into a mechanism. In such cases the collapse is unavoidable. Therefore, the soft stories deserve a special consideration in analysis and design
Behavioural Study of RC Flat Plate Multi-Storey Building Persuaded By Stiffne...IJERA Editor
With a very swift development in urban areas the framed structures which are infilled by brick masonry or
concrete blocks are widely used as partition walls and also exterior walls. Masonry infill walls are common
element in structural system which modifies the conduction of building under the lateral load. These structures
resist the moderate earthquakes and accomplish well in such a prime manner that even if they have no load
bearing function. Evidently, during the time of resolution of such a multi-storey structure, the infilled frame is
considered as bare frame, because IS codes do not provide any guide lines for the analysis and design of RC
frames with infill wall. This paper addresses the numerical study of G+10 RC flat plate framed building with
different cases i.e, soft story at ground level (Basement), with soft story at 5th floor level, without soft storey and
bare frame building by using ETABS as soft computing tool. All these cases are analyzed for equivalent static
method and Response spectrum method. By this, dynamic properties are evaluated and according to the results
obtained conclusions are drawn
Dynamic Analysis of Soft Storey Frame with IsolatorsIJMTST Journal
Soft storey buildings are very common in Indian housing construction and the bottom storey is left open without walls for car parking. Past earthquakes showed that these kinds of buildings performed poor and the damages are also heavy. As the base isolation is a technique developed to prevent or minimize damage to building during an earthquake, this study focuses on the time history analysis of a soft-storey building with and without lead rubber isolator. The soft-storey building with and without isolator is analysed using Elcenrto earthquake data and the dynamic characteristics are compared.
Seismic Performance Evaluation of Multi-Storeyed R C Framed Structural System...IJERA Editor
Masonry infills are normally considered as non-structural elements and their stiffness contributions are generally ignored in practice. But they affect both the structural and non-structural performance of the RC buildings during earthquakes. RC frame building with open first storey is known as soft storey, which performs poorly during strong earthquake shaking. A similar soft storey effect can also appear at top storey level if a storey used as a service storey. Hence a combination of two structural system components i.e. Rigid frames and RC shear walls leads to a highly efficient system in which shear wall resist the majority of the lateral loads and the frame supports majority of the gravity loads. To study the effect of masonry infill and different soft storey level, 11 models of R C framed building were analyzed with two types of shear wall when subjected to earthquake loading. The results of bare frame and other building models have been compared, it is observed that model with swastika and L shape shear wall with core wall are showing efficient performance and hence reducing the effect of soft storey and also reducing the effect of water pressure in the top soft storey.
Fragility analysis of open ground storey rc building designed using various m...eSAT Journals
Abstract The vulnerability of an element is defined as the probability that the said element will sustain a specified degree of structural damage given a certain level of ground motion severity. Significantly low stiffness and strength in any storeys compared to adjacent storeys is generally referred to as soft ground storey. As the columns of this Open ground storey are weakest element, ground storey is most vulnerable. Open ground storey framed buildings are generally analyzed in practice ignoring infill wall stiffness (linear bare frame analysis). Design codes impose a multiplication factor on the design forces in the columns of ground storey. The present study attempts to estimate and compare performance of open ground storey building designed with three different multiplication factors given by Indian code and Israel code. Thus fragility curves are derived using nonlinear dynamic time history analysis carried on a (G+9) OGS building by using method suggested by Cornell. Probabilistic seismic demand models are developed by using power law model. Results show that performance of upper storeys while applying multiplication factor only to the ground storey needs to be checked. The first storey is more vulnerable than the ground storey except for Israel code. Keywords: Open ground storey, multiplication factors, fragility, performance levels, PSDM Model
Lateral Load Analysis of Shear Wall and Concrete Braced Multi-Storeyed R.C Fr...ijsrd.com
Generally RC framed structures are designed without regards to structural action of masonry infill walls present. Masonry infill walls are widely used as partitions. These buildings are generally designed as framed structures without regard to structural action of masonry infill walls. They are considered as non- structural elements. RC frame building with open first storey is known as soft storey, which performs poorly during strong earthquake shaking. Past earthquakes are evident that collapses due to soft storeys are most often in RC buildings. In the soft storey, columns are severely stressed and unable to provide adequate shear resistance during the earthquake. . In this study, 3D analytical model of twelve storeyed buildings have been generated for different buildings Models and analyzed using structural analysis tool 'ETABS'. To study the effect of infill, ground soft, bare frame and models with ground soft having concrete core wall and shear walls and concrete bracings at different positions during earthquake; seismic analysis using both linear static, linear dynamic (response spectrum method) has been performed. The analytical model of the building includes all important components that influence the mass, strength, stiffness and deformability of the structure.
Seismic Response of RC Framed Buildings with Open Ground StoreyIJERA Editor
RC framed buildings are generally designed without considering the structural action of masonry infill walls. These masonry infill walls are widely used as partitions and considered as non-structural elements. But they affect both the structural and non-structural performance of RC buildings during earthquake. RC framed building with open ground storey is known as soft storey, which performs poorly during earthquake. In order to study this total 144 RC framed buildings having bare frame, full infill frame and open ground storey frame were analyzed by seismic coefficient method and response spectrum method for various seismic hazards. The present study deals with the comparison of base shear for medium rise RC framed buildings having P+5, P+7, P+9 and P+11 storeys for various seismic zones (III, IV & V) and for various soil conditions (Hard & Medium) as per IS 1893(part 1): 2002. This work helps in understanding the effect of earthquake with increase in height of RC framed buildings on base shear for various seismic zones and soil conditions. The result shows that the effect of infill stiffness on structural response is significant under lateral loads. It is found that the presence infill walls increases the base shear by 60-65% more than bare frame by both seismic coefficient method and response spectrum method.
Numerical Optimization of Shoring Towers for Slab Formwork SystemsIJTET Journal
The usage of Shoring Tower for slab formwork is getting increased due to not only because of flexibility in the assemble and
construction over Prop-Supported Slab Formwork but also the capacity to withstand maximum construction working loads. The Shoring Tower is
generally used for the construction of heavy structures like Bridges, Culverts, staging of Retaining walls, etc. However a comprehensive scale down
of the shoring tower design goes well with the large span and increased slab thickness of conventional buildings. This research focuses primarily on
Analysis, Modelling, Design and Adaptability of shoring tower for slab formwork through computer models and optimized. The different models are
made from the combination of diameter of tubes with slab thickness and also with plywood thickness in Solid Works. Periodic analysis is done in
ANSYS for different load combinations with the variations of slab thickness and plywood thickness will gives the optimized results for the slab
formwork systems.
Effect of different infill material on the seismic behavior of high rise buil...eSAT Journals
Abstract Many urban multistory buildings in India today have open first storey as an unavoidable feature. This is primarily being adopted to accommodate parking or reception lobbies in the first stories. Also for offices or for any other purpose such as communication hall etc. The construction of reinforced concrete structures with infill wall is a common method of providing shelter to the ever increasing population, where there is seismic activity. In the present work, the effect of different infill materials on the seismic behavior of high rise building with soft stories is studied. For that, G+11 RCC model is selected. Different infill materials like siporex and Laminated glass are used. Different cases considering different location of soft stories are considered for the analysis. To study the effect of different infill material on high rise structure, linear dynamic analysis (Response spectrum analysis) in software ETABs is carried out. Seismic parameters like time period, base shear, storey displacement and storey drift are checked out Keywords: soft storey, infill material, response spectrum method, ETABs
LATERAL LOAD ANALYSIS OF SOFT STORY BUILDING AND IMPORTANCE OF MODELING MASON...ijsrd.com
Generally Masonry infills are considered as non-structural elements and their stiffness contributions are generally ignored in practice. But they affect both the structural and non-structural performance of the RC buildings during earthquakes. RC frame building with open first storey is known as soft storey, which performs poorly during strong earthquake shaking. A similar soft storey effect can occur if first and second story used as service story. Hence a combination of two structural system components i.e. Rigid frames and RC shear walls leads to a highly efficient system in which shear wall resist the majority of the lateral loads and the frame supports majority of the gravity loads. To study the effect of masonry infill with different soft storey level, 7 models of Reinforced Concrete framed building were analyzed with two types of shear wall when subjected to earthquake loading. The results of bare frame and other building models have been compared, it is observed that model with swastika and L shape shear wall are showing efficient performance and hence reducing the effect of soft storey in model 3, model 4 and model 5.
Seismic evaluation of rc framed buildings with influence of masonry infill paneleSAT Journals
Abstract
RC framed buildings are generally designed without considering the structural action of masonry infill walls present. These walls are
widely used as partitions and considered as non-structural elements. But they affect both the structural and non-structural
performance of the RC buildings during earthquakes. RC framed building with open first storey is known as soft storey, which
performs poorly during earthquakes. A similar soft storey effect can also appear below plinth, when the ground material has removed
during excavation and refilled later. To observe the effect of masonry infill panel, it is modeled as an equivalent diagonal strut. In
order to study these six RC framed buildings with brick masonry infill were designed for the same seismic hazard. In the present paper
an investigation has been made to study the behavior of RC frames with various arrangement of infill when subjected to earthquake
loading. The results of bare frame, frame with infill, soft ground floor, soft basement and infill in swastika pattern in ground floor are
compared and conclusions are made. It is observed that, providing infill below plinth and in swastika pattern in the ground floor
improves earthquake resistant behavior of the structure when compared to soft basement.
Key words: masonry infill panel, bare frame, soft basement, diagonal strut.
Earthquake Resistant Design of Low-Rise Open Ground Storey Framed BuildingIJMER
Presence of infill walls in the frames alters the behavior of the building under lateral loads.
However, it is common industry practice to ignore the stiffness of infill wall for analysis of framed
building. Engineers believe that analysis without considering infill stiffness leads to a conservative
design. An existing RC framed building (G+3) with open ground storey located in Seismic Zone-V is
considered for this study. This building is analyzed for two different cases: (a) considering both infill
mass and infill stiffness and (b) considering infill mass but without considering infill stiffness. Two
separate models were generated using commercial software SAP2000. Infill weights were modelled
through applying static dead load and corresponding masses considered from this dead load for
dynamic analyses. Infill stiffness was modelled using a diagonal strut approach. Two different support
conditions, namely fixed end support condition and pinned end support condition, are considered to
check the effect of support conditions in the multiplication factors. Linear and non-linear analyses were
carried out for the models and the results were compared.
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CFD analysis is incredibly effective at solving mysteries and improving the performance of complex systems!
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It is always satisfying when we can help solve complex challenges like this. Do your systems also need a check-up or optimization? Give us a call!
Work done in cooperation with James Malloy and David Moelling from Tetra Engineering.
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Quality defects in TMT Bars, Possible causes and Potential Solutions.PrashantGoswami42
Maintaining high-quality standards in the production of TMT bars is crucial for ensuring structural integrity in construction. Addressing common defects through careful monitoring, standardized processes, and advanced technology can significantly improve the quality of TMT bars. Continuous training and adherence to quality control measures will also play a pivotal role in minimizing these defects.
Cosmetic shop management system project report.pdfKamal Acharya
Buying new cosmetic products is difficult. It can even be scary for those who have sensitive skin and are prone to skin trouble. The information needed to alleviate this problem is on the back of each product, but it's thought to interpret those ingredient lists unless you have a background in chemistry.
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Final project report on grocery store management system..pdfKamal Acharya
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Static Analysis of Masonry Infilled R.C.Frame With &Without Opening Including Soft Storey of Symmetric Building
1. IOSR Journal of Mechanical and Civil Engineering (IOSR-JMCE)
e-ISSN: 2278-1684,p-ISSN: 2320-334X, Volume 8, Issue 1 (Jul. - Aug. 2013), PP 78-87
www.iosrjournals.org
www.iosrjournals.org 78 | Page
Static Analysis of Masonry Infilled R.C.Frame With &Without
Opening Including Soft Storey of Symmetric Building
Nikhil S. Agrawal1,
Prof. P. B Kulkarni2
P.G. Student1
, Civil Engineering Department, Shri.Ramdeobaba College of Engineering and Management,
Nagpur-440012, Maharashtra, India1
Associate Professor2
, Civil Engineering Department, Shri.Ramdeobaba College of Engineering and
Management Nagpur-440012, Maharashtra, India2
Abstract: Masonry infill is considered as a non-structural element in all type of buildings where masonry use.
But, masonry infill walls are mainly used to increase initial stiffness and strength of reinforced concrete (RC)
frame buildings. This Open First storey is also termed as “Soft Storey”. The upper storeys have brick infilled
wall panels with various opening percentage in it. In many cities of India, it is very common to leave the first
storey of masonry infilled reinforcement concrete (RC) frame building open preliminary to generate parking
space or any other usage in the first storey. Such buildings are highly undesirable in seismically active areas. In
the present study, it is an attempt to access the performance of masonry infilled reinforced concrete (RC) frames
with soft storey of with and without opening. In this paper, symmetrical frame of college building (G+5) located
in seismic zone-III is considered by modelling of initial frame. According to FEMA-273, & ATC-40 which
contain the provisions of calculation of stiffness of infilled frames by modelling infill as“Equivalent Diagonal
Strut Method”. Therefore, the infill panels are modelled as equivalent diagonal strut method. The error
involved in modelling such buildings as neglecting the presence of infills in the upper storeys, is brought out
through the study of an example building with different analytical models. This linear static analysis is to be
carried out on the models such as Strut frame with 15%, 20%, & 25% centre &corner opening, which is
performed by using computer software STAAD-Pro from which different parameters are computed. In which it
shows that how infill panels increase the stiffness of the structure. While the increase in the opening percentage
leads to a decrease on the lateral stiffness of infilled frame. This paper highlights the importance of the presence
of the open first storey in the analysis of the building.
Keywords: Masonry infilled frame, Stiffness, Equivalent Diagonal Strut Method, Seismic Effect, Opening
percentage.
I. Introduction
Many urban multistorey buildings in India today have open first storey as an unavoidable feature. This
leave the open first storey of masonry infilled reinforced concrete frame building primarily to generate parking
or reception lobbies in the first storey. It has been known for long time that masonry infill walls affect the
strength & stiffness of infilled frame structures. There are plenty of researches done so far for infilled frames,
however partially infill frames are still the topic of interest. Though it has been understood that the infill’s play
significant role in enhancing the lateral stiffness of complete structures.Infills have been generally considered as
non-structural elements & their influence was neglected during the modeling phase of the structure. A soft
storey building is a multi-storey building with one or more floors which are “soft” due to structural design.
These floors can be especially dangerous in earthquakes. As a result, the soft storey may fail, causing what is
known as a soft storey collapse. Soft storey buildings are characterized by having a storey which has a lot of
open space. Parking garages, for example, are often soft stories, as are large retail spaces or floors with a lot of
windows. While the unobstructed space of the soft storey might be aesthetically or commercially desirable, it
also means that there are less opportunities to install shear walls, specialized walls which are designed to
distribute lateral forces. If a building has a floor which is 70% less stiff than the floor above it, it is considered a
soft storey building. This soft storey creates a major weak point in an earthquake, and since soft stories are
classically associated with reception lobbies retail spaces and parking garages, they are often on the lower
stories of a building, which means that when they collapse, they can take the whole building down with them,
causing serious structural damage which may render the structure totally unusable. As per Indian standard
1893 (part –I) 2002 code (BIS-2002) some design criteria are to be adopted after carrying out the earthquake
analysis ,in which the columns and beams of the soft stories are the designed for 2.5 times the storey shears and
moments calculated under seismic loads.
2. Static Analysis of Masonry Infilled R.C.Frame With &Without Opening Including Soft Storey of
www.iosrjournals.org 79 | Page
II. ANALYTICAL METHODS
Static or dynamic analysis can be classified into three broad categories, namely elastic analysis, plastic
analysis and nonlinear analysis. Elastic analysis refers to the analysis where a linear elastic behaviour is
assumed for the frame and the infill, and geometric and material nonlinearities are not included. In the case of a
plastic analysis, an elastic-plastic stress-strain relationship is assumed for the materials, and the failure load of
the in filled frame corresponding to collapse stage is determined. In the nonlinear analysis, the different sources
of nonlinearity are included, and the response of the structure is traced in the entire loading range, from
precracking to collapse. For most applications, codes of practice recommend an elastic analysis, because of the
inherent complexity of a nonlinear analysis. The different models available for the elastic analysis of infilled
frames can be classified into four groups based on their complexity. They are the stress function method, the
equivalent diagonal strut method, the equivalent frame method and the finite element method.
III. Equivalent Diagonal Strut Methods
The simplest equivalent strut model includes a single pin-jointed strut. Holmes who replaced the infill
by an equivalent pin-jointed diagonal strut made of the same material and having the same thickness as the infill
panel suggest a width defined by,
𝑤
𝑑
=
1
3
……………. (3.3.1)
Paulay and Priestley [32] suggested the width of equivalent strut as,
𝑤 = 0.25𝑑 ……………. (3.3.2)
Where,
d = Diagonal length of infill panel
w = Depth of diagonal strut
However, researchers later found that this model overestimates the actual stiffness of infilled frames
and give upper bound values. Another model for masonry infill panels was proposed by Mainstone in 1971
where the cross sectional area of strut was calculated by considering the sectional properties of the adjoining
columns. The details of model are as shown in Fig. 4.2. The strut area As was given by the following equation..
Ae = W t
W= 0.175 (ʎ H)-0.4
D
Fig.1 Brick Infill Panel As Equivalent Diagonal Strut
Where,
Ei = the modules of elasticity of the infill material, N/mm2
Ef= the modules of elasticity of the frame material, N/mm2
Ic= the moment of inertia of column, mm4
t = the thickness of infill, mm
H =the centre line height of frames
h = the height of infill
L =the centre line width of frames
l = the width of infill
D = the diagonal length of infill panel
θ = the slope of infill diagonal to the horizontal.
Infills frame with Opening: Area of opening, Aopis normalized with respect to area of infill panel, Ainfilland the
ratio is termed as opening percentage (%).
3. Static Analysis of Masonry Infilled R.C.Frame With &Without Opening Including Soft Storey of
www.iosrjournals.org 80 | Page
IV. ANALYSIS EXAMPLE
STRUCTURAL DETAIL
Symmetrical View of Building
The above mentioned frame has been designed by using STAAD-Pro software. For getting results
some column has been selected for getting results and they are as column no.1,2 The results shown in the form
of
DEFLECTION
AXIAL FORCE
MOMENT
AST
V. Analytical Models Considered
1) Model I. Open Ground Storey of Strut Frame With 15% Centre Opening (RC Frame with Masonry Infill
S.M.R.F. Frame)
2) Model II.Open Ground Storey of Strut Frame With 15% Corner Opening (RC Frame with Masonry Infill
S.M.R.F. Frame)
3) Model III. Open Ground Storey of Strut Frame With 20% Centre Opening (RC Frame with Masonry Infill
S.M.R.F. Frame)
Type of structure COLLEGE BUILDING (G+5)
ZONE III
FOUNDATION LEVEL TO
GROUND LEVEL
1 M
FLOOR TO FLOOR HEIGHT 4M
EXTERNAL WALL 230 MM
INTERNAL WALL 230 MM
LIVE LOAD 5 KN/M2
MATERIAL M20 AND Fe415
SEISMIC ANALYSIS EQUIVALENT STATIC METHOD (IS 1893
(Part I) - 2002)
SIZE OF COLUMN C1= 300X700
C2= 400X750
SIZE OF BEAM B1=300X500
B2=300X400
DEPTH OF SLAB 140 MM
DESIGN PHILOSOPHY LIMIT STATE METHOD CONFORMING (IS 456-2000)
DUCTILE DETAILING CODE IS 13920-1993
4. Static Analysis of Masonry Infilled R.C.Frame With &Without Opening Including Soft Storey of
www.iosrjournals.org 81 | Page
4) Model IV. Open Ground Storey of Strut Frame With 20% Corner Opening (RC Frame with Masonry Infill
S.M.R.F. Frame)
5) Model III. Open Ground Storey of Strut Frame With 25% Centre Opening (RC Frame with Masonry Infill
S.M.R.F. Frame)
6) Model IV. Open Ground Storey of Strut Frame With 25% Corner Opening (RC Frame with Masonry Infill
S.M.R.F. Frame)
VI. Materials:
a) Concrete:
Concrete with following properties is considered for study.
Characteristic compressive strength (fck) = 20 MPa
Poisson’s Ratio = 0.3
Density = 25 kN/m3
Modulus of Elasticity (E) = 5000 x √ fck = 22360.67 MPa
b) Steel :
Steel with following properties is considered for study.
Yield Stress (fy) = 415 MPa
Modulus of Elasticity (E) = 2x105
MPa
c) Masonry infill
Clay burnt brick, Class A, confined unreinforced masonry
Compressive strength of Brick, fm = 10 MPa
Modulus of Elasticity of masonry (Ei) = 550 x fm = 5500MPa
Poisson’s Ratio = 0.15
Fig6.1; MODEL I: BARE FRAME Fig6.2;MODEL II: WITH FULLY INFILLED FRAME
Fig6.3; MODEL III:INFILLED FRAME WITH CENTRE Fig6.4; MODEL IV : INFILLED FRAME WITH CORNER
OPENING OPENING
5. Static Analysis of Masonry Infilled R.C.Frame With &Without Opening Including Soft Storey of
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Fig6.5; Example of Strut Frame Model
VII. Comparison of Results
Here, Comparison is done in between bare frame and centre and corner opening only. And it is shown with the
help of bar graph.
BAR GRAPH
Fig.7.1 BAR GRAPH FOR DEFLECTION
20.02 18.21 20.53 18.08 22.58 18.94
1
DEFLECTION (MM) FOR COLUMN NO. 1
15% centre opening 15% corner opening
20% centre opening 20% corner opening
25%centre opening 25%corner opening
20.49 18.44 20.78 18.29
22.92 19.19
1
DEFLECTION (MM) FOR COLUMN NO. 2
15% centre opening 15% corner opening
20% centre opening 20% corner opening
25%centre opening 25%corner opening
6. Static Analysis of Masonry Infilled R.C.Frame With &Without Opening Including Soft Storey of
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Fig.7.2 BAR GRAPH FOR AXIAL FORCE
21.05 18.13
21.93 19.12
22.56 19.68
1
DEFLECTION (MM) FOR COLUMN NO. 3
15% centre opening 15% corner opening
20% centre opening 20% corner opening
25%centre opening 25%corner opening
1125.8
1149.79
1112.74
1148.92
1084.97
1137.67
1
AXIAL FORCE(kN) FOR COLUMN NO. 1
15% centre opening 15% corner opening
20% centre opening 20% corner opening
25%centre opening 25%corner opening
1362.45
1354.6
1338.9 1344.33
1357.36 1354.18
1
AXIAL FORCE(kN) FOR COLUMN NO. 2
15% centre opening 15% corner opening
20% centre opening 20% corner opening
25%centre opening 25%corner opening
2217.03
2184.43
2200.37
2169.94
2227.72
2194.23
1
AXIAL FORCE(kN) FOR COLUMN NO.3
15% centre opening 15% corner opening
20% centre opening 20% corner opening
25%centre opening 25%corner opening
7. Static Analysis of Masonry Infilled R.C.Frame With &Without Opening Including Soft Storey of
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Fig.7.3 BAR GRAPH FOR TOP MOMENT
27.4 32.49
107.94 104.87
23.76
104.03
1
TOP MOMENT(kN-M)FORCOLUMN NO.1
15% centre opening 15% corner opening
20% centre opening 20% corner opening
25%centre opening 25%corner opening
28.05 29.5
106.27 104.7
26.32
106.28
1
TOP MOMENT(kN-M)FORCOLUMN NO.2
15% centre opening 15% corner opening
20% centre opening 20% corner opening
25%centre opening 25%corner opening
-173.17 -171.7
173.89 172.19
-174.17
172
1
TOP MOMENT(kN-M)FORCOLUMN NO.3
15% centre opening 15% corner opening
20% centre opening 20% corner opening
25%centre opening 25%corner opening
8. Static Analysis of Masonry Infilled R.C.Frame With &Without Opening Including Soft Storey of
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Fig.7.4 BAR GRAPH FOR BOTTOM MOMENT
103.96
101.13
105.79
102.06
106.22
102.15
1
BOTTOMMOMENT(kN-M)FORCOLUMN NO.1
15% centre opening 15% corner opening
20% centre opening 20% corner opening
25%centre opening 25%corner opening
102.08
100.49
102.89
100.87
103.36
100.62
1
BOTTOMMOMENT(kN-M)FORCOLUMN NO .2
15% centre opening 15% corner opening
20% centre opening 20% corner opening
25%centre opening 25%corner opening
175.1
172.07
176.67
172.85
177.55
173
1
BOTTOMMOMENT(KN-M)FOR COLUMN NO.3
15% centre opening 15% corner opening
20% centre opening 20% corner opening
25%centre opening 25%corner opening
9. Static Analysis of Masonry Infilled R.C.Frame With &Without Opening Including Soft Storey of
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Fig.7.5 BAR GRAPH FOR AREA OF STEEL
4872
4704
4872
4704
4872
4704
1
AST(MM^2)FOR COLUMN NO.1
15% centre opening 15% corner opening
20% centre opening 20% corner opening
25%centre opening 25%corner opening
4872
4704
4872
4704
4872
4704
1
AST(MM^2)FOR COLUMN NO.2
15% centre opening 15% corner opening
20% centre opening 20% corner opening
25%centre opening 25%corner opening
6000 6000 6000 6000 6000 6000
1
AST(MM^2)FOR COLUMN NO.3
15% centre opening 15% corner opening
20% centre opening 20% corner opening
25%centre opening 25%corner opening
10. Static Analysis of Masonry Infilled R.C.Frame With &Without Opening Including Soft Storey of
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VIII. Conclusion
1. Infill Panels Increase Stiffness of The Structure.
2. The Maximum In Deflection In Bare Frame For (G+5) Is 105.05mm And In Strut Frame It Is Minimum
Which 17.84mm At Highest Storey Level Is. If The Effect Of Infill Wall Is Considered Then The
Deflection Has Reduced Drastically.
3. The Maximum Deflection In Infilled Frame For (G+5) With 15% Centre Opening Is 21.05mm Which Is
21.93mm In 20% Centre Opening And 23.59mm In 25% Centre Opening. Hence, As The Opening
Percentage Increases It Leads To Increase In Deflection Respectively.
4. The Maximum Axial Force In Infilled Frame For (G+5) With 15% Centre Opening Is 2217.03kN Which Is
2200.37 kN In 20% Centre Opening And 2227.72 kN In 25% Centre Opening. Hence, As The Opening
Percentage Increases It Leads To Increase In Axial Force Respectively.
5. The Maximum Deflection In Infilled Frame For (G+5) With 15% Centre Opening Is 21.05mm And
18.44mm In 15% Corner Opening. Thus The Deflection In Centre Opening Is More Than The Corner
Opening.
6. From This Present Result It Shows That, Deflection Is Very Large In Case Of Bare Frame As Compare To
That Of Infill Frame With Opening. If The Effect Of Infill Wall Is Considered Then The Deflection Has
Reduced Drastically. And Also Deflection Is More At Last Storey Because Earthquake Force Acting On It
More Effectively.
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