1) The document presents the results of a linear and non-linear analysis of reinforced concrete frames with members of varying inertia (non-prismatic beams) for buildings ranging from G+2 to G+10 storeys.
2) Both bare frames and frames with infill walls were analyzed considering different beam cross-sections - prismatic, linear haunch, parabolic haunch, and stepped haunch.
3) The linear analysis was performed using ETABS and considered parameters like fundamental time period, base shear, and top storey displacement. The non-linear analysis used pushover analysis in SAP2000 to determine effective time period, effective stiffness, and hinge formation patterns.
Evaluation of the Seismic Response Parameters for Infilled Reinforced Concret...IOSRJMCE
RC frames with unreinforced masonry infill walls are a common form of construction all around the world. Often, engineers do not consider masonry infill walls in the design process because the final distribution of these elements may be unknown to them, or because masonry walls are regarded as non-structural elements. Separation between masonry walls and frames is often not provided and, as a consequence, walls and frames interact during strong ground motion. This leads to structural response deviating radically from what is expected in the design. The presence of masonry infills can result in higher stiffness and strength and it is cheap and built with low cost labor. Under lateral load, Masonry walls act as diagonal struts subjected to compression, while reinforced concrete confining members (Frames) act in tension and/or compression, depending on the direction of lateral earthquake forces. The main objective of this research is to develop a realistic matrix for the response modification factors for medium-rise skeletal buildings with masonry infills. In this study, the contribution of the masonry infill walls to the lateral behavior of reinforced concrete buildings was investigated. For this purpose, a five, seven and ten stories buildings are modelled as bare and infilled frames. The parameters investigated were infill ratio, panel aspect ratio, unidirectional eccentricity, bidirectional eccentricities. A Parametric study was developed on the behavior of medium rise infilled frame buildings under lateral loads to investigate the effect of these parameters as well as infill properties on this behavior
Performance based analysis of rc building consisting shear wall and varying i...Yousuf Dinar
Abstract:
Metropolitan cities are under severe threat because of inappropriate design and construction of structures. Faulty building designed without considering seismic consideration could be vulnerable to damage even under low levels of ground shaking from distant earthquake. So, structural engineers often are more concerned about the constructing Shear wall without knowing its performance with respect to infill percentage which may lead it to an over design state without knowing the demand. Nonlinear inelastic pushover analysis provides a better view about the behavior of the structures during seismic events. This study investigates as well as compares the performances of bare, different infill percentage level and two types of Shear wall consisting building structures and suggests from which level of performance shear wall should be preferred over the infill structure. To perform the finite element simulation ETABS 9.7.2 is used to get the output using pushover analysis. For different loading conditions, the performances of structures are evaluated with the help of base shear, deflection, storey drift, storey drift ratio and stages of number of hinges form and represented with discussion.
Effect of steel bracing on vertically irregular r.c.c building frames under s...eSAT Journals
Abstract
Earthquakes are one of the most life threatening, environmental hazardous and destructive natural phenomenons that causes
shaking of ground. This result in damage to the structures, hence we need to design the buildings to withstand these earthquakes
which may occur at least once in the life time of the structure. Structures possess less stiffness and strength in case of irregular
configured frames; to enhance this, lateral load resisting systems are introduced into the frames. In this study, G+5 storey
building model has been analyzed considering different types of vertical geometric irregularities and steel bracings using
pushover analysis with the help of ETABS 9.7 software. Addition of X type brace, V type Brace and Inverted V/K type brace shows
that use of X-type of bracing is found more suitable to enhance the performance of the irregular buildings.
Key Words: pushover analysis, vertical irregularity, steel bracings, performance point.
Evaluation of the Seismic Response Parameters for Infilled Reinforced Concret...IOSRJMCE
RC frames with unreinforced masonry infill walls are a common form of construction all around the world. Often, engineers do not consider masonry infill walls in the design process because the final distribution of these elements may be unknown to them, or because masonry walls are regarded as non-structural elements. Separation between masonry walls and frames is often not provided and, as a consequence, walls and frames interact during strong ground motion. This leads to structural response deviating radically from what is expected in the design. The presence of masonry infills can result in higher stiffness and strength and it is cheap and built with low cost labor. Under lateral load, Masonry walls act as diagonal struts subjected to compression, while reinforced concrete confining members (Frames) act in tension and/or compression, depending on the direction of lateral earthquake forces. The main objective of this research is to develop a realistic matrix for the response modification factors for medium-rise skeletal buildings with masonry infills. In this study, the contribution of the masonry infill walls to the lateral behavior of reinforced concrete buildings was investigated. For this purpose, a five, seven and ten stories buildings are modelled as bare and infilled frames. The parameters investigated were infill ratio, panel aspect ratio, unidirectional eccentricity, bidirectional eccentricities. A Parametric study was developed on the behavior of medium rise infilled frame buildings under lateral loads to investigate the effect of these parameters as well as infill properties on this behavior
Performance based analysis of rc building consisting shear wall and varying i...Yousuf Dinar
Abstract:
Metropolitan cities are under severe threat because of inappropriate design and construction of structures. Faulty building designed without considering seismic consideration could be vulnerable to damage even under low levels of ground shaking from distant earthquake. So, structural engineers often are more concerned about the constructing Shear wall without knowing its performance with respect to infill percentage which may lead it to an over design state without knowing the demand. Nonlinear inelastic pushover analysis provides a better view about the behavior of the structures during seismic events. This study investigates as well as compares the performances of bare, different infill percentage level and two types of Shear wall consisting building structures and suggests from which level of performance shear wall should be preferred over the infill structure. To perform the finite element simulation ETABS 9.7.2 is used to get the output using pushover analysis. For different loading conditions, the performances of structures are evaluated with the help of base shear, deflection, storey drift, storey drift ratio and stages of number of hinges form and represented with discussion.
Effect of steel bracing on vertically irregular r.c.c building frames under s...eSAT Journals
Abstract
Earthquakes are one of the most life threatening, environmental hazardous and destructive natural phenomenons that causes
shaking of ground. This result in damage to the structures, hence we need to design the buildings to withstand these earthquakes
which may occur at least once in the life time of the structure. Structures possess less stiffness and strength in case of irregular
configured frames; to enhance this, lateral load resisting systems are introduced into the frames. In this study, G+5 storey
building model has been analyzed considering different types of vertical geometric irregularities and steel bracings using
pushover analysis with the help of ETABS 9.7 software. Addition of X type brace, V type Brace and Inverted V/K type brace shows
that use of X-type of bracing is found more suitable to enhance the performance of the irregular buildings.
Key Words: pushover analysis, vertical irregularity, steel bracings, performance point.
Seismic analysis of vertical irregular multistoried buildingeSAT Journals
Abstract It is understood that buildings which are regular in elevation (regular building) perform much better than those which have irregularity in elevation (irregular building) under seismic loading. Irregularities are not avoidable in construction of buildings. However a detailed study to understand structural behaviour of the buildings with irregularities under seismic loading is essential for appropriate design and their better performance. The main objective of this study is to understand the effect of elevation irregularity and behaviour of 3-D R.C. Building which is subjected to earthquake load. In the present study, a 5 bays X 5 bays, 16 storied structure with provision of lift core walls and each storey height 3.2 m, having irregularity in elevation, is considered as the soft storey 3-D structure. An Irregular building is assumed to be located in all zones. Linear dynamic analysis using Response Spectrum method of the irregular building is carried out using the standard and convenient FE software package. To quantify the effect of different degrees of irregularities all the structures are analysed. In addition, the analysis carried out also enables to understand the behaviour that takes place in irregular buildings in comparison to that in regular buildings. For this the behaviour parameters considered are 1) Maximum displacement 2) Base shear, 3) Time period. Key Words: asymmetric building, soft story, base shear, displacement, soft storey, time period.
seismic response of multi storey building equipped with steel bracingINFOGAIN PUBLICATION
Steel bracing has proven to be one of the most effective systems in resisting lateral loads. Although its use to upgrade the lateral load capacity of existing Reinforced Concrete (RC) frames has been the subject of numerous studies, guidelines for its use in newly constructed RC frames still need to be developed. In this paper the study reveals that seismic performance of moment resisting RC frames with different patterns of bracing system. The three different types of bracings were used i.e. X - bracing system, V - bracing system and Inverted V - bracing system. This arrangement helped in reducing the structural response (i.e. displacement, interstorey drift, Shear Forces & Bending Moments) of the designed building structure. An (G+6) storey building was modelled and designed as per the code provisions of IS-1893:2002. And linear analysis is been carried out in the global X direction. The analysis was conducted with a view of accessing the seismic elastic performance of the building structure.
Determination of period of vibration of buildings with open stilt floor and s...eSAT Journals
Abstract To estimate the natural period of vibration, codes consign the empirical formula that solely relies on height of the structure. Present dissertation is carried out considering aspects such as building material, type of structure and structural dimensions. The foremost objective of the present systematic study has led to a simplified period-height equation for use in the seismic evaluation of reinforced concrete structures, taking due significance of the existence of stilt floors and shear walls. Current study also highlights the criteria that affects the period of vibration. The period of vibration which has been procured in this study represents the time period of first mode of vibration. This article comprises the seismic response of structures on different types of soil. The parameters considered for the given study are three different types of soil i.e., soft soil, medium soil and hard rock for high seismic zone and different building irregularities as per IS: 1893-2002 for 10, 15, 20 storey buildings. The analytical models for the modulus study are modeled through ETABS.V.9.2. Various parametric studies are carried out to determine the fundamental time period of the structures. These ameliorate formulas to determine the fundamental time period are developed using nonlinear regression analysis through ORIGIN pro software. The generalized equation finally obtained can be used in general form to calculate the time period of structures with open stilt floor and shear walls irrespective of soil types, seismic zone or building height. Keywords- Time period, open stilt floor, Shear walls, Irregularities in buildings, nonlinear regression
Seismic Capacity Comparisons of Reinforced Concrete Buildings Between Standar...drboon
Earthquakes are cause of serious damage through the building. Therefore, moment resistant frame buildings are widely used as lateral resisting system. Generally three types of moment resisting frames are designed namely Special ductile frames (SDF), Intermediate ductile frames (IDF) and Gravity load designed (GLD) frames, each of which has a certain level of ductility. Comparative studies on the seismic performance of three different ductility of building are performed in this study. The analytical models are considered about failure mode of column (i.e. shear failure, flexural to shear failure and flexural failure); beam-column joint connection, infill wall and flexural foundation. Concepts of incremental dynamic analysis are practiced to assess the required data for performance based evaluations. This study found that the lateral load capacity of GLD, IDF, and SDF building was 19.25, 27.87, and 25.92 %W respectively. The average response spectrum at the collapse state for GLD, IDF, and SDF are 0.75 g, 1.19 g, and 1.33 g, respectively. The results show that SDF is more ductile than IDF and the initial strength of SDF is close to IDF. The results indicate that all of frames are able to resistant a design earthquake.
Effect of vertical discontinuity of columns in r.c frames subjected to differ...eSAT Journals
Abstract Majority of structural systems are designed with various levels of irregularities in accordance with architectural requirements in order to produce aesthetic buildings. Irregular structures come into being due to discontinuity in mass, stiffness and strength in elevation and due to asymmetric geometrical conCharturation on plane. One of the irregularities in elevation is discontinuity of columns. In the present study, effects of the structural irregularity which is produced by the discontinuity of a columns in RC space frames subjected to different wind loads was investigated. Investigation was carried out for R.C space frames, with and without vertical discontinuity of columns for G+5, G+10 & G+15 storeys, assumed to be located in different wind zones in India. Both regular and irregular structures were analysed using STAADPro. From the study, it was concluded that frames without vertical discontinuity of the columns having more stiffness when compared to frames with vertical discontinuity of columns. Keywords: Structural irregularity, Vertical discontinuity, Discontinuity of columns, Wind loads.
PERFORMANCE BASED ANALYSIS OF VERTICALLY IRREGULAR STRUCTURE UNDER VARIOUS SE...Ijripublishers Ijri
In the recent years a lot of attention has been given to the earthquake analysis of structure it is one of the most devastating
natural calamity and which causes severe damage not only to the properties but also to the lives. This is the
reason there has been a lot of focus on the structures to be earthquake resistant. Buildings get damaged mostly due
to the earthquake ground motions. In an earthquake, the building base experiences high frequency movements, which
results in the inertial force on the building and its components and this problem gets worse when a structure is irregular
in shape, size etc,. Therefore, there is a lot to work on the seismic behavior of the irregular building which might not
respond the way regular building does. It makes the irregular building quite more complex and unpredictable during
the course of an earthquake.
Strengthening of RC Framed Structure Using Energy Dissipation DevicesIOSR Journals
A large numbers of existing buildings in India are severely deficient against earthquake forces and
the number of such buildings is growing very rapidly. This paper presents a way of using energy dissipation
devices for seismic strengthening of a RC framed structure. The objective was to improve the seismic
performance of the building to resist the earthquake. The viscous dampers are used as an energy dissipation
device in the form of single, double, inverted V, V type of dampers with different percentages of damping such
as 10%, 20% and 30% to prevent building from collapse in a major earthquake and also to control the damage
during earthquake. The performance of the buildings is assessed as per the procedure prescribed in ATC-40
and FEMA 356.
Review on seismic performance of multi storied rc building with soft storeyeSAT Journals
Abstract Soft storey is a storey in which the stiffness is less than 70% of the storey above or less than 80% of the combined stiffness of three storeys above. In a multi-storied building, soft storey is adopted to accommodate parking which is an unavoidable feature. This open ground storey is vulnerable to collapse during earthquake. Soft storey in a building causes stiffness irregularity in a structure. Due to this the structures undergoes unequal storey drift, formation of plastic hinges and finally collapse. The presence of infill wall improves the performance of building under the lateral forces. This paper deals with the study of literature of previous researches. These researches focus on the combination of measures adopted on the structure to reduce the effect of soft storey through static and dynamic analysis. The parameters studied in these researches are storey drift, axial and shear forces bending moment, displacement, time period, base shear. Also, it focuses on the equivalent strut approach to consider the effect of infill wall on the performance on building. From these researches, the interest arises to perform static and dynamic analysis to reduce the stiffness irregularity which is the main reason behind the poor performance of the building with soft storey. Keywords: Soft storey, Stiffness, Storey drift, Lateral Displacement, Infill wall
Seismic analysis of vertical irregular multistoried buildingeSAT Journals
Abstract It is understood that buildings which are regular in elevation (regular building) perform much better than those which have irregularity in elevation (irregular building) under seismic loading. Irregularities are not avoidable in construction of buildings. However a detailed study to understand structural behaviour of the buildings with irregularities under seismic loading is essential for appropriate design and their better performance. The main objective of this study is to understand the effect of elevation irregularity and behaviour of 3-D R.C. Building which is subjected to earthquake load. In the present study, a 5 bays X 5 bays, 16 storied structure with provision of lift core walls and each storey height 3.2 m, having irregularity in elevation, is considered as the soft storey 3-D structure. An Irregular building is assumed to be located in all zones. Linear dynamic analysis using Response Spectrum method of the irregular building is carried out using the standard and convenient FE software package. To quantify the effect of different degrees of irregularities all the structures are analysed. In addition, the analysis carried out also enables to understand the behaviour that takes place in irregular buildings in comparison to that in regular buildings. For this the behaviour parameters considered are 1) Maximum displacement 2) Base shear, 3) Time period. Key Words: asymmetric building, soft story, base shear, displacement, soft storey, time period.
seismic response of multi storey building equipped with steel bracingINFOGAIN PUBLICATION
Steel bracing has proven to be one of the most effective systems in resisting lateral loads. Although its use to upgrade the lateral load capacity of existing Reinforced Concrete (RC) frames has been the subject of numerous studies, guidelines for its use in newly constructed RC frames still need to be developed. In this paper the study reveals that seismic performance of moment resisting RC frames with different patterns of bracing system. The three different types of bracings were used i.e. X - bracing system, V - bracing system and Inverted V - bracing system. This arrangement helped in reducing the structural response (i.e. displacement, interstorey drift, Shear Forces & Bending Moments) of the designed building structure. An (G+6) storey building was modelled and designed as per the code provisions of IS-1893:2002. And linear analysis is been carried out in the global X direction. The analysis was conducted with a view of accessing the seismic elastic performance of the building structure.
Determination of period of vibration of buildings with open stilt floor and s...eSAT Journals
Abstract To estimate the natural period of vibration, codes consign the empirical formula that solely relies on height of the structure. Present dissertation is carried out considering aspects such as building material, type of structure and structural dimensions. The foremost objective of the present systematic study has led to a simplified period-height equation for use in the seismic evaluation of reinforced concrete structures, taking due significance of the existence of stilt floors and shear walls. Current study also highlights the criteria that affects the period of vibration. The period of vibration which has been procured in this study represents the time period of first mode of vibration. This article comprises the seismic response of structures on different types of soil. The parameters considered for the given study are three different types of soil i.e., soft soil, medium soil and hard rock for high seismic zone and different building irregularities as per IS: 1893-2002 for 10, 15, 20 storey buildings. The analytical models for the modulus study are modeled through ETABS.V.9.2. Various parametric studies are carried out to determine the fundamental time period of the structures. These ameliorate formulas to determine the fundamental time period are developed using nonlinear regression analysis through ORIGIN pro software. The generalized equation finally obtained can be used in general form to calculate the time period of structures with open stilt floor and shear walls irrespective of soil types, seismic zone or building height. Keywords- Time period, open stilt floor, Shear walls, Irregularities in buildings, nonlinear regression
Seismic Capacity Comparisons of Reinforced Concrete Buildings Between Standar...drboon
Earthquakes are cause of serious damage through the building. Therefore, moment resistant frame buildings are widely used as lateral resisting system. Generally three types of moment resisting frames are designed namely Special ductile frames (SDF), Intermediate ductile frames (IDF) and Gravity load designed (GLD) frames, each of which has a certain level of ductility. Comparative studies on the seismic performance of three different ductility of building are performed in this study. The analytical models are considered about failure mode of column (i.e. shear failure, flexural to shear failure and flexural failure); beam-column joint connection, infill wall and flexural foundation. Concepts of incremental dynamic analysis are practiced to assess the required data for performance based evaluations. This study found that the lateral load capacity of GLD, IDF, and SDF building was 19.25, 27.87, and 25.92 %W respectively. The average response spectrum at the collapse state for GLD, IDF, and SDF are 0.75 g, 1.19 g, and 1.33 g, respectively. The results show that SDF is more ductile than IDF and the initial strength of SDF is close to IDF. The results indicate that all of frames are able to resistant a design earthquake.
Effect of vertical discontinuity of columns in r.c frames subjected to differ...eSAT Journals
Abstract Majority of structural systems are designed with various levels of irregularities in accordance with architectural requirements in order to produce aesthetic buildings. Irregular structures come into being due to discontinuity in mass, stiffness and strength in elevation and due to asymmetric geometrical conCharturation on plane. One of the irregularities in elevation is discontinuity of columns. In the present study, effects of the structural irregularity which is produced by the discontinuity of a columns in RC space frames subjected to different wind loads was investigated. Investigation was carried out for R.C space frames, with and without vertical discontinuity of columns for G+5, G+10 & G+15 storeys, assumed to be located in different wind zones in India. Both regular and irregular structures were analysed using STAADPro. From the study, it was concluded that frames without vertical discontinuity of the columns having more stiffness when compared to frames with vertical discontinuity of columns. Keywords: Structural irregularity, Vertical discontinuity, Discontinuity of columns, Wind loads.
PERFORMANCE BASED ANALYSIS OF VERTICALLY IRREGULAR STRUCTURE UNDER VARIOUS SE...Ijripublishers Ijri
In the recent years a lot of attention has been given to the earthquake analysis of structure it is one of the most devastating
natural calamity and which causes severe damage not only to the properties but also to the lives. This is the
reason there has been a lot of focus on the structures to be earthquake resistant. Buildings get damaged mostly due
to the earthquake ground motions. In an earthquake, the building base experiences high frequency movements, which
results in the inertial force on the building and its components and this problem gets worse when a structure is irregular
in shape, size etc,. Therefore, there is a lot to work on the seismic behavior of the irregular building which might not
respond the way regular building does. It makes the irregular building quite more complex and unpredictable during
the course of an earthquake.
Strengthening of RC Framed Structure Using Energy Dissipation DevicesIOSR Journals
A large numbers of existing buildings in India are severely deficient against earthquake forces and
the number of such buildings is growing very rapidly. This paper presents a way of using energy dissipation
devices for seismic strengthening of a RC framed structure. The objective was to improve the seismic
performance of the building to resist the earthquake. The viscous dampers are used as an energy dissipation
device in the form of single, double, inverted V, V type of dampers with different percentages of damping such
as 10%, 20% and 30% to prevent building from collapse in a major earthquake and also to control the damage
during earthquake. The performance of the buildings is assessed as per the procedure prescribed in ATC-40
and FEMA 356.
Review on seismic performance of multi storied rc building with soft storeyeSAT Journals
Abstract Soft storey is a storey in which the stiffness is less than 70% of the storey above or less than 80% of the combined stiffness of three storeys above. In a multi-storied building, soft storey is adopted to accommodate parking which is an unavoidable feature. This open ground storey is vulnerable to collapse during earthquake. Soft storey in a building causes stiffness irregularity in a structure. Due to this the structures undergoes unequal storey drift, formation of plastic hinges and finally collapse. The presence of infill wall improves the performance of building under the lateral forces. This paper deals with the study of literature of previous researches. These researches focus on the combination of measures adopted on the structure to reduce the effect of soft storey through static and dynamic analysis. The parameters studied in these researches are storey drift, axial and shear forces bending moment, displacement, time period, base shear. Also, it focuses on the equivalent strut approach to consider the effect of infill wall on the performance on building. From these researches, the interest arises to perform static and dynamic analysis to reduce the stiffness irregularity which is the main reason behind the poor performance of the building with soft storey. Keywords: Soft storey, Stiffness, Storey drift, Lateral Displacement, Infill wall
A comparative study of various diagnostic techniques for CryptosporidiosisIOSR Journals
Diarrhoeal disease is a common complication of infection with HIV. Cryptosporidium has gained importance as an AIDS indicator disease and a cause of intractable diarrhoea in immunosuppressed individuals. This warranted a study of stool specimens of HIV positive patients with (n=60) and without (n=60) diarrhoea along with their HIV negative counterparts (n=200). Microscopic examination for ova and cysts were done using wet mount and Lugol’s iodine preparation. Smears were stained with Kinyoun Cold Acid Fast (KCAF) and Auramine ‘O’ fluorochrome (AOF) staining methods to identify Cryptosporidium oocysts. ELISA using Cryptosporidium microplate assay (alexon Inc) for detection of Cryptosporidium antigen was conducted on all stool specimens. By KCAF staining detection of Cryptosporidium in HIV positive subjects with diarrhoea was 20%, by AOF it was 7.5% and by ELISA the detection rate went up to 30%. All the detailed result were statistically compared taking KCAF staining as gold standard which revealed AOF staining to have sensitivity of 36.67% and specificity of 99.31% while ELISA was found to have sensitivity of 83.88% and specificity of 96.55%. Keeping in mind the present scenario of HIV infection in India and more so in Goa, it is recommended to include detection of Cryptosporidium oocysts in routine parasitological examination of stool specimens and an urgent need to standardize a gold standard for various diagnostic tests presently available
Performance of Flat Slab Structure Using Pushover AnalysisIOSR Journals
Performance Based Seismic Engineering is the modern approach to earthquake resistant design. It
is a limit-state based design approach extended to cover complex range of issues faced by structural engineers.
Flat slabs are becoming popular and gaining importance as they are economical as compared to beam-column
connections in conventional slab. Many existing flat slabs may not have been designed for seismic forces so it is
important to study their response under seismic conditions and to evaluate seismic retrofit schemes. In this
paper we have discussed the results obtained by performing push over analysis on flat slabs by using most
common software SAP2000. A (G+7) frame having 5 bays is considered for analysis. It is observed that the
performance point of flat slab is more as compared to conventional building.
Seismic performance of r c buildings on sloping grounds with different types ...eSAT Journals
Abstract
Structure are highly susceptible to serve damages in earthquake scenario, so choosing an appropriate lateral force resisting
bracing systems will have a significant effect on performance of the structure. So this present study is aimed at evaluating and
comparing various types of eccentric steel bracings for 12 storey RC frame building resisting on sloping ground configurations.
For this 5 types of bracing systems like X-Bracing, Diagonal bracing, K- bracing, V-bracing and inverted V bracing are
considered on the outer periphery of the buildings with step back and set back – step back type configurations are modeled and
analyzed. The models are compared for different aspects within the structure, such as the maximum storey displacement, base
shear, storey drift and storey shear, the structure is analyzed for seismic zone V and medium soil condition as per IS 1893:2002
using ETABS software. Results conclude that on sloping ground due to irregularity on ground surface, the structures are more
vulnerable to earthquakes. Hence use of eccentric steel bracing is an effective and economical way to resist earthquake forces,
Inverted V type bracing performs well compared to other bracing types. By using inverted V type bracing in step back buildings
types maximum storey displacement of 70% and storey drift of 66% are obtained. Similarly for setback – step back configuration
maximum storey displacement of 74% and storey drift of 70% are obtained respectively.
Keywords: X-Bracing, Diagonal Bracing, K- Bracing, V-Bracing and Inverted V Bracing
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
Analysis and Capacity Based Earthquake Resistance Design of Multy Bay Multy S...IJERA Editor
Many reinforced concrete (RC) framed structures located in zones of high seismicity in India are constructed
without considering the seismic code provisions. The vulnerability of inadequately designed structures represents
seismic risk to occupants. The main cause of failure of multi-storey reinforced concrete frames during seismic
motion is the sway mechanism. If the frame is designed on the basis of strong column-weak beam concept the
possibilities of collapse due to sway mechanisms can be completely eliminated. In multi storey frame this can be
achieved by allowing the plastic hinges to form, in a predetermined sequence only at the ends of all the beams
while the columns remain essentially in elastic stage and by avoiding shear mode of failures in columns and
beams. This procedure for design is known as Capacity based design which would be the future design
philosophy for earthquake resistant design of multi storey reinforced concrete frames. Model of multi bay multi
storied residential building study were done using the software program ETAB2015 and were analyzed using
non-linear static pushover analysis
Comparative Analysis of Frames with Varying InertiaIJERA Editor
This paper presents an elastic seismic response of reinforced concrete frames with 3 variations of heights, i.e. (G+2), (G+4), (G+6) storey models are compared for bare frame and frame with brick infill structures which have been analyzed for gravity as well as seismic forces and their response is studied as the geometric parameters varying from view point of predicting behavior of similar structures subjected to similar loads or load combinations. In this study, two different cases are selected i.e. frames with prismatic members and frames with non-prismatic members. The structural response of various members when geometry changes physically, as in case of linear and parabolic haunches provided beyond the face of columns at beam column joints or step variations as in case of stepped haunches was also studied. Frames have been analyzed statically as well as dynamically using ETABS-9.7.4 software referring IS: 456-2000, IS: 1893 (Part-1)2002 and the results so obtained are grouped into various categories.
Descriptive study of pushover analysis in rcc structures of rigid jointYousuf Dinar
ABSTRACT: Structures in mega cities, are under serious threat because of faulty and unskilled design and construction of structures. Sometimes structure designers are more concerned in constructing different load resistant members without knowing its necessity and its performance in the structure. Different configuration of construction may also lead to significant variation in capacity of the same structure. Nonlinear static pushover analysis provides a better view on the performance of the structures during seismic events. This comprehensive research evaluates as well as compares the performances of bare, different infill percentage level, different configuration of soft storey and Shear wall consisting building structures with each other and later depending upon the findings, suggests from which level of performance shear wall should be preferred over the infill structure and will eventually help engineers to decide where generally the soft storey could be constructed in the structures. Above all a better of effects of pushover analysis could be summarized from the findings. Masonry walls are represented by equivalent strut according to pushover concerned codes. For different loading conditions, the performances of structures are evaluated with the help of performance point, base shear, top displacement, storey drift and stages of number of hinges form.
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F012515059
1. IOSR Journal of Mechanical and Civil Engineering (IOSR-JMCE)
e-ISSN: 2278-1684,p-ISSN: 2320-334X, Volume 12, Issue 5 Ver. I (Sep. - Oct. 2015), PP 50-59
www.iosrjournals.org
DOI: 10.9790/1684-12515059 www.iosrjournals.org 50 | Page
Linear and Non-Linear Analysis of Reinforced Concrete
Frames with Members of Varying Inertia
Prerana Nampalli1
, Prakarsh Sangave2
1
(Post Graduate Student, Department of Civil Engineering, Nagesh Karajagi Orchid College of Engg. and
Tech., Solapur, India)
2
(Associate Professor, Department of Civil Engineering, Nagesh Karajagi Orchid College of Engg. and Tech.,
Solapur, India)
Abstract: Beams are major media of carrying and transferring loads. A careful approach in its design may
lead to good serviceability and optimization of the cost of structure. Prismatic beams are commonly used for
medium span and bending moments. As the span increases, bending moments and shear forces increases
substantially at the centre of span and over the supports. Hence, prismatic beams may become uneconomical in
such cases. Moreover, with the increased depth there is considerable decrease in headroom. Therefore in such
cases non-prismatic beams are an appealing solution.In the present study, linear and non-linear analysis of
reinforced concrete buildings with members of varying inertia has been carried out for buildings of (G+2),
(G+4), (G+6), (G+8) and (G+10) storey. Further, two cases are considered, one is bare frame (without infill
walls) and another one is frame with infill (considering infill walls). The buildings are analyzed for severe
earthquake load (seismic zone V of India). Linear analysis of frames has been done using two methods Seismic
Coefficient Method and Response Spectrum Method. Non-linear analysis of frames has been done using
Pushover Analysis as per ATC 40 and FEMA 356 guidelines. Beams in x direction are made non-prismatic,
Linear Haunch, Parabolic Haunch and Stepped Haunch are considered. The linear analysis is performed using
ETABS 9.7.4 and non-linear analysis is performed using SAP2000.The linear analysis has been performed on
the building to identify the effect of varying inertia on various response parameters such as base shear,
displacement and member forces. The nonlinear analysis has been performed to determine the capacity
spectrum curve, performance levels and hinge formation patterns of the considered buildings. Due to inclusion
of non-prismatic members, moments in the members have varied significantly but forces in the members haven’t
varied much as well as it leads to the formation of strong beam and weak column.
Keywords: Non-Prismatic Members, Base Shear, Time Period, Storey Displacement, Seismic Coefficient
Method, Response Spectrum Method and Pushover Analysis.
I. Introduction
In last few years the widespread damage to reinforced concrete building during earthquake generated
demand for seismic evaluation and retrofitting of existing buildings in Indian sub-continents. In addition, most
of our buildings built in past decades are seismically deficient because of lack of awareness regarding structural
behavior during earthquake and reluctance to follow the code guidelines. Due to scarcity of land, there is
growing responsiveness of multi-storied reinforced concrete structures to accommodate growing population. In
developing countries, multi-storied buildings are generally provided with prismatic sections. Structural
engineers should design the structures in such a way that the structural systems perform their functions
satisfactorily and at the same time the design should prove to be economical. This helps to choose the right type
of sections consistent with economy along with safety of the structure. Beams are major media of carrying and
transferring loads. A careful approach in its design may lead to good serviceability and optimization of the cost
of structure. Prismatic beams are commonly used for medium span and bending moments. As the span
increases, bending moments and shear forces increases substantially at the centre of span and over the supports.
Hence, prismatic beams may become uneconomical in such cases. Moreover, with the increased depth there is
considerable decrease in headroom. Therefore in such cases non-prismatic beams are an appealing solution.
The non-prismatic members having varying depths are frequently used in the form of haunched beams
for bridges, portal frames, cantilever retaining walls etc. The cross-section of the beams can be made non-
prismatic by varying width, depth, or by varying both depth and width continuously or discontinuously along
their length. Variation in width causes difficulty in construction. Therefore, beams with varying depth are
generally provided. Either the soffit or top surface of the beam can be inclined to obtain varying cross-section,
but the former practice is more common. The soffit profile may have triangular or parabolic haunches. Effective
depth of such beams varies from point to point and the internal compressive and tensile stress resultants are
inclined. It makes the analysis of such beams slightly different from prismatic beams. The inclination of internal
stress resultant may significantly affect the shear for which the beam should be designed. The aim of the present
2. Linear and Non-Linear Analysis of Reinforced Concrete Frames with Members of Varying…
DOI: 10.9790/1684-12515059 www.iosrjournals.org 51 | Page
work is to study the effect of non-prismatic members in multistoried RC frames, with respect to various building
performance levels. The work also aims at studying the linear and non-linear behavior of frames with varying
inertia.
II. Methodology
2.1 Equivalent Static Method
Seismic analysis of most structures is still carried out on the assumption that the lateral (horizontal)
force is equivalent to the actual (dynamic) loading. This method requires less effort because, except for the
fundamental period, the periods and shapes of higher natural modes of vibration are not required. The base shear
which is the total horizontal force on the structure is calculated on the basis of the structures mass, its
fundamental period of vibration, and corresponding shape. The base shear is distributed along the height of the
structure in terms of lateral force according to Codal formula. Planar models appropriate for each of the two
orthogonal lateral directions are analyzed separately, the results of the two analyses and the various effects,
including those due to torsional motions of the structure, are combined. This method is usually conservative for
low to medium-height buildings with a regular configuration.
2.2 Response Spectrum Method
This method is also known as Modal Method or Mode Super-Position Method. This method is
applicable to those structures where modes other than the fundamental one significantly affect the response of
structures. Generally, this method is applicable to analysis of the dynamic response of structures, which are
asymmetrical or have geometrical areas of discontinuity or irregularity, in their linear range of behaviour. In
particular, it is applicable to analysis of forces and deformation in multi-storey buildings due to intensity of
ground shaking, which causes a moderately large but essentially linear response in the structure.
This method is based on the fact that, for certain forms of damping which are reasonable models for
many buildings the response in each natural mode of vibration can be computed independently of the others, and
the modal responses can be combined to determine the total response. Each mode responds with its own
particular pattern of deformation (mode shape), with its own frequency (the modal frequency), and with its own
modal damping.
2.3 Non-Liner Static Pushover Analysis
Pushover analysis which is an iterative procedure is looked upon as an alternative for the conventional
analysis procedures. Pushover analysis of multi-story RCC framed buildings subjected to increasing lateral
forces is carried out until the preset performance level (target displacement) is reached. The promise of
performance-based seismic engineering (PBSE) is to produce structures with predictable seismic performance.
The recent advent of performance based design has brought the non-linear static push over analysis
procedure to the forefront. Pushover analysis is a static non-linear procedure in which the magnitude of the
structural loading along the lateral direction of the structure is incrementally increased in accordance with a
certain pre-defined pattern. It is generally assumed that the behaviour of the structure is controlled by its
fundamental mode and the predefined pattern is expressed either in terms of story shear or in terms of
fundamental mode shape. With the increase in magnitude of lateral loading, the progressive non-linear
behaviour of various structural elements is captured, and weak links and failure modes of the structure are
identified. In addition, pushover analysis is also used to ascertain the capability of a structure to withstand a
certain level of input motion defined in terms of a response spectrum. Pushover analysis is of two types:
(i) Force Controlled
(ii) Displacement Controlled.
In the force control, the total lateral force is applied to the structure in small increments. In the
displacement control, the displacement of the top storey of the structure is incremented step by step, such that
the required horizontal force pushes the structure laterally. The distance through which the structure is pushed,
is proportional to the fundamental horizontal translational mode of the structure. In both types of pushover
analysis, for each increment of the load or displacement, the stiffness matrix of the structure may have to be
changed, once the structure passes from the elastic state to the inelastic state. The displacement controlled
pushover analysis is generally preferred over the force controlled one because the analysis could be carried out
up to the desired level of the displacement.
III. Description of Analytical Model
The R.C. moment resisting frame models with prismatic and non-prismatic members are developed.
Material properties, geometry and loading conditions of different models are as follows:
3.1 Material Properties
3. Linear and Non-Linear Analysis of Reinforced Concrete Frames with Members of Varying…
DOI: 10.9790/1684-12515059 www.iosrjournals.org 52 | Page
Density of concrete and brick masonry is taken as 25 KN/ m3
and 20 KN/m3
respectively. M-25 grade
of concrete and Fe 500 grade of reinforcing steel are used for all the frame models considered in this study. The
modulus of elasticity for concrete and brick masonry is taken as 25000MPa and 1225MPa respectively.
3.2 Geometry and Loading Conditions
In the present study, Bare frames and Frames with infill situated in seismic zone V are considered with
variations of heights, i.e. (G+2), (G+4), (G+6), (G+8) and (G+10). Depending upon different height of building,
depth of foundation is taken as 1.5m for (G+2) and (G+4) buildings, 2.0m (G+6), (G+8) and (G+10) buildings.
The storey height taken is 4m (for all models). The analytical model consists of single bay of 10m in global X
direction and 5 bays of 3m each in Y direction. Beams in X direction are made non-prismatic. Three types of
non-prismatic members are developed which includes linear haunch (LH), parabolic haunch (PH) and stepped
haunch (SH). In the model, the support condition is assumed to be fixed and soil condition is assumed as
medium soil.
The size of beam in X direction is taken as 250mmX710mm (for prismatic member) and
230mmX530mm (medium soil) in Y direction. Length of haunch is taken as 1000mm, depth of haunch at centre
as 675mm and depth of haunch at supports as 1000mm, width of haunch is 250mm. Sizes of columns have been
varied according to loading conditions. Thickness of slab as well as brick wall is taken as 150 mm; floor finish
load is 1 KN/m2
, Live load on floor slabs is 4 KN/m2
. Seismic coefficient method is used for static analysis and
Response spectrum method is used for dynamic analysis. And non-linear analysis has been performed by using
Static Pushover Analysis.
The plan, elevations in X direction of different frames, elevation in Y direction of frame with prismatic
members for G+2 bare frame structure considered in this study are as shown in Figures 4.1 to 4.6. Detailed
features of building are shown in Table 4.1.
Figure 4.1: Plan of Building
Figure 4.2: Elevation of Frame with Prismatic Figure 4.3: Elevation of Frame with Linear
member in X direction haunch in X direction
4. Linear and Non-Linear Analysis of Reinforced Concrete Frames with Members of Varying…
DOI: 10.9790/1684-12515059 www.iosrjournals.org 53 | Page
Figure 4.4: Elevation of Frame with Parabolic Figure 4.5: Elevation of Frame with Stepped
haunch in X direction haunch in X direction
Figure 4.6: Elevation of Frame with Prismatic member in Y direction
IV. Results
The linear analysis is performed using ETABS 9.7.4 and non-linear analysis is performed using
SAP2000. The response of structures has been studied in the form of base shear, displacement, effective time
period, effective stiffness and pattern of hinge formation. The results of various parameters are presented in the
form of Figures from 4.7 to 4.17 and Tables from 4.1 to 4.4 respectively. The observations for each parametric
variation are stated as under respective tables and graphs.
4.1 Fundamental Time Period (sec.)
Natural period of a structure is its time period of undamped free vibration. It is the first (longest) modal
time period of vibration. Variation of Fundamental Time Period for various height of structure is shown in
Figures 4.7 and 4.8.
5. Linear and Non-Linear Analysis of Reinforced Concrete Frames with Members of Varying…
DOI: 10.9790/1684-12515059 www.iosrjournals.org 54 | Page
Figure 4.7: Variation of Time Period (sec.) for Bare Frame
Figure 4.8: Variation of Time Period (sec.) for Frame with Infill
4.2 Base Shear (KN)
It is the total design lateral force at the base of the structure. Variation of Base Shear in X as well as Y
direction has been studied.
4.2.1 Variation of Base Shear in X direction for G+8 building is shown in Figures 4.9 and 4.10.
Figure 4.9: Variation of Base Shear in X direction for G+8 Bare Frame in KN
Figure 4.10: Variation of Base Shear in X direction for G+8 Frame with Infill in KN
6. Linear and Non-Linear Analysis of Reinforced Concrete Frames with Members of Varying…
DOI: 10.9790/1684-12515059 www.iosrjournals.org 55 | Page
4.2.2 Variation of Base Shear in Y direction for G+8 building is shown in Figures 4.11 and 4.12.
Figure 4.11: Variation of Base Shear in Y direction for G+8 Bare Frame in KN
Figure 4.12: Variation of Base Shear in Y direction for G+8 Frame with Infill in KN
4.3 Top Storey Displacements (mm)
It is the lateral displacement at the top floor of frame. The Displacements are observed for EQx case.
The variation of displacements for G+8 building is shown in Figures 4.13 and 4.14.
Figure 4.13: Variation of Displacement for G+8 Bare Frame in mm
7. Linear and Non-Linear Analysis of Reinforced Concrete Frames with Members of Varying…
DOI: 10.9790/1684-12515059 www.iosrjournals.org 56 | Page
Figure 4.14: Variation of Displacement for G+8 Frame with Infill in mm
4.4 Effective Time Period (sec.)
An effective period, Te, is generated from the initial period, Ti, by a graphical procedure using an
idealized force-deformation curve (i.e., pushover curve) relating base shear to roof displacement, which
accounts for some stiffness loss as the system begins to behave inelastically. The effective period represents the
linear stiffness of the equivalent SDOF system. The effective period is used to determine the equivalent SDOF
system’s spectral acceleration, Sa, using an elastic response spectrum. The time period is evaluated by
coefficient method using FEMA 356. The variation of time period for G+8 building is shown in Figure 4.15.
Figure 4.15: Variation of Effective Time Period in Sec. for Both Bare Frame and Frame with Infill for
G+8 Building
4.5 Effective Stiffness (KN/m)
An effective stiffness is generated from the effective time period, Te, by a graphical procedure using an
idealized force-deformation curve (i.e., pushover curve) relating base shear to roof displacement. The stiffness is
evaluated by coefficient method using FEMA 356. The variation of stiffness for G+8 building is shown in
Figure 4.16.
Figure 4.16: Variation of Effective Stiffness in KN/m for Both Bare Frame and Frame with Infill for G+8
Building
8. Linear and Non-Linear Analysis of Reinforced Concrete Frames with Members of Varying…
DOI: 10.9790/1684-12515059 www.iosrjournals.org 57 | Page
4.6 Behavior Factor
Behavior Factor is the ratio of the strength required to maintain the structure elastic to the inelastic
design strength of the structure. The Behavior Factor, R, accounts for the inherent ductility and over strength of
a structure and the difference in the level of stresses considered in its design. The behavior factor is evaluated by
coefficient method using FEMA 356. The variation of behavior factor for G+8 building is shown in Figure 4.17.
Figure 4.17: Variation of Behavior Factor for Both Bare Frame and Frame with Infill for G+8 Building
4.7 Performance Point
Performance point can be obtained by superimposing capacity spectrum and demand spectrum and the
intersection point of these two curves is performance point. The capacity spectrum method by ATC 40 is used
for the analysis. The variation of performance point for models with various height is shown in Tables 4.1 to
4.4.
Table 4.1 - Variation of Performance Point (X Direction) for Bare Frame
Height of
building
Bare Frame
Frame with prismatic
member
Frame with non-prismatic member
LH PH SH
G+2 1784.539, 0.087 3249.912, 0.084 3141.130, 0.084 3268.090, 0.083
G+4 2671.643, 0.141 3379.193, 0.132 3276.421, 0.138 3283.244, 0.137
G+6 2831.661, 0.183 3441.970, 0.179 3436.777, 0.180 3471.096, 0.175
G+8 2857.323, 0.240 3651.904, 0.221 3607.774, 0.244 3619.093, 0.240
G+10 2955.526, 0.284 3729.465, 0.205 3716.732, 0.269 3738.891, 0.264
Table 4.2 - Variation of Performance Point (X Direction) for Frame with Infill
Height of
building
Frame with Infill
Frame with prismatic
member
Frame with non-prismatic member
LH PH SH
G+2 4623.484, 0.062 5181.029, 0.061 5165.931, 0.061 5204.198, 0.060
G+4 4921.175, 0.101 5208.899, 0.093 5193.205, 0.099 5194.538, 0.098
G+6 4969.660, 0.132 5370.330, 0.129 5323.116, 0.130 5476.917, 0.129
G+8 5418.087, 0.165 5741.666, 0.174 5723.116, 0.173 5753.055, 0.173
G+10 5463.872, 0.206 5944.483, 0.199 5924.067, 0.200 5973.659, 0.198
Table 4.3 - Variation of Performance Point (Y Direction) for Bare Frame
Height of
building
Bare Frame
Frame with prismatic
member
Frame with non-prismatic member
LH PH SH
G+2 2707.685, 0.0004 3087.336, 0.0005 3081.464, 0.0005 3093.093, 0.0005
G+4 3015.447, 0.0007 3231.153, 0.0004 3226.159, 0.0004 3427.802, 0.0004
G+6 3245.416, 0.0004 3545.293, 0.0004 3425.473, 0.0004 3633.467, 0.0004
G+8 3714.820, 0.0001 3951.829, 0.0004 3902.435, 0.0004 4003.343, 0.0004
G+10 4196.640, 0.0005 4292.717, 0.0004 4277.516, 0.0004 4378.321, 0.0004
9. Linear and Non-Linear Analysis of Reinforced Concrete Frames with Members of Varying…
DOI: 10.9790/1684-12515059 www.iosrjournals.org 58 | Page
Table 4.4 - Variation of Performance Point (Y Direction) for Frame with Infill
Height of
building
Frame with Infill
Frame with prismatic
member
Frame with non-prismatic member
LH PH SH
G+2 6260.098, 0.00015 6751.468, 0.00013 6561.648, 0.00013 6957.028, 0.00013
G+4 6788.384, 0.00011 7038.806, 0.00009 6932.022, 0.00010 7139.045, 0.00010
G+6 7185.300, 0.00020 7206.429, 0.00010 7177.943, 0.00020 7390.525, 0.00020
G+8 7440.820, 0.00020 7516.904, 0.00030 7423.116, 0.00030 7548.206, 0.00030
G+10 7490.705, 0.00070 7620.195, 0.00060 7524.684, 0.00050 7659.932, 0.00050
V. Conclusions
In the present study, linear and non-linear analysis of reinforced concrete buildings is carried out with
varying inertia for different storey height. Further, two cases are considered, one is bare frame analysis (without
infill walls) and another one is frame with infill (considering infill walls). The buildings are analyzed for very
severe earthquake load (seismic zone V). Comparison is made between various parameters as base shear, storey
displacement, member forces, performance levels, patterns of hinge formation.
Based on the analysis results for all cases considered, following conclusions are drawn:
1) Frames with prismatic member have lesser base shear and higher storey displacement as compared to
Frames with non-prismatic member as the stiffness of Frames with prismatic member is less than Frames
with non-prismatic member.
2) Frames with parabolic haunch have lesser base shear and higher storey displacement as compared to
Frames with linear haunch and Frames with stepped haunch as the stiffness of Frames with parabolic
haunch is less than Frames with linear haunch.
3) Due to inclusion of non-prismatic members, behaviour and failure modes of buildings change. The results
show the importance of considering varying inertia in modeling, to get the real scenario of damage.
4) Response Spectrum Method predicts lesser base shear and lesser storey displacement as compared to
Seismic Coefficient Method.
5) Pushover analysis produces higher base shear and higher storey displacement as compared to Seismic
Coefficient Method and Response Spectrum Method.
6) Due to absence of strength and stiffness effect of infill in bare frame analysis, it leads to under estimation
of base shear as compared to infilled frame.
7) From pushover analysis results the weak links in the structure are identified and the performance level
achieved by structure is known. This helps to find the retrofitting location to achieve the performance
objective.
8) Frames with prismatic member have higher effective time period, lesser effective stiffness and higher
behavior factor as compared to Frames with non-prismatic member.
9) Frames with parabolic haunch have higher effective time period, lesser effective stiffness and lesser
behavior factor as compared to Frames with linear haunch and Frames with stepped haunch.
10) The performance point of frames with non-prismatic member is higher than that of frames with prismatic
member for bare frames and frames with infill.
11) For bare frames as well as frames with infill analyzed by both PUSH in x direction and PUSH in y
direction, the performance point of frames with parabolic haunch are lesser than frames with linear
haunch. Whereas the performance point of frames with stepped haunch are higher than frames with linear
haunch.
In the present study, variation of haunch dimensions is not considered. Therefore work can be repeated
by changing haunch dimensions. Addition of shear wall especially for multistoried building can be done.
Variation of storey height is not considered in the present work. Therefore work can be repeated by changing
storey height. The study of varying inertia can be done by considering T- beam action. All the analysis can be
done for different seismic parameters.
Acknowledgement
The present authors Prerana Nampalli and Prof. Prakarsh Sangave thank Dr. J. B. Dafedar, Principal,
Nagesh Karajagi Orchid College of Engg. and Tech., Solapur, for his invaluable support on this research. The
authors also thank Prof. Metan S., Dept. of Mechanical Engg., Nagesh Karajagi Orchid College of Engg. and
Tech., Solapur, for guiding regarding paper writing skills.
10. Linear and Non-Linear Analysis of Reinforced Concrete Frames with Members of Varying…
DOI: 10.9790/1684-12515059 www.iosrjournals.org 59 | Page
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