Reinforced concrete (RC) frames such as bare frames, soft story frames and completely
infilled fr... more Reinforced concrete (RC) frames such as bare frames, soft story frames and completely infilled frames were considered for model in this study. Each frame was further considered as 6, 9, 12 and 15 story buildings. Soft story and infilled frames were provided with two types of masonry infill (Em = 1875 and 5625 N/mm2). Frames were subjected to harmonic ground motions of peak ground acceleration 1, 2 and 3 m/s2. Each acceleration was of 12 frequency levels starting from .25 to 3 Hz. The duration of the ground motions was taken as 5s and damping of RC buildings was assumed to be 5%. The study was nonlinear dynamic analysis of the models using ETABS 2013. Natural frequency, interstory drift ratio and time passed before collapse were considered to analyze the response of the RC frames. The UBC limitation on drift ratio for long period (≥.7s) structures is .02. The structures were assumed to fail at this drift ratio. After performing time history analysis, behaviors of the structures are compared. It was found that when subjected to ground motion infilled frames perform best. Strength of infill has effect on the response of frames under seismic loading and also on the natural frequencies of the frames. Completely infilled frames with higher strength infill performed better. Structures with higher number of story were found to sustain seismic loading for longer duration before failure. The response of soft story and infilled frames (12 and 15 story buildings) were found to be close if weak infills are used. When subjected to ground motions, frames were vulnerable to frequency level up to 1.5 Hz.
Reinforced concrete (RC) frames such as bare frames, soft story frames and completely
infilled fr... more Reinforced concrete (RC) frames such as bare frames, soft story frames and completely infilled frames were considered for model in this study. Each frame was further considered as 6, 9, 12 and 15 story buildings. Soft story and infilled frames were provided with two types of masonry infill (Em = 1875 and 5625 N/mm2). Frames were subjected to harmonic ground motions of peak ground acceleration 1, 2 and 3 m/s2. Each acceleration was of 12 frequency levels starting from .25 to 3 Hz. The duration of the ground motions was taken as 5s and damping of RC buildings was assumed to be 5%. The study was nonlinear dynamic analysis of the models using ETABS 2013. Natural frequency, interstory drift ratio and time passed before collapse were considered to analyze the response of the RC frames. The UBC limitation on drift ratio for long period (≥.7s) structures is .02. The structures were assumed to fail at this drift ratio. After performing time history analysis, behaviors of the structures are compared. It was found that when subjected to ground motion infilled frames perform best. Strength of infill has effect on the response of frames under seismic loading and also on the natural frequencies of the frames. Completely infilled frames with higher strength infill performed better. Structures with higher number of story were found to sustain seismic loading for longer duration before failure. The response of soft story and infilled frames (12 and 15 story buildings) were found to be close if weak infills are used. When subjected to ground motions, frames were vulnerable to frequency level up to 1.5 Hz.
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infilled frames were considered for model in this study. Each frame was further
considered as 6, 9, 12 and 15 story buildings. Soft story and infilled frames were provided
with two types of masonry infill (Em = 1875 and 5625 N/mm2). Frames were subjected to
harmonic ground motions of peak ground acceleration 1, 2 and 3 m/s2. Each acceleration
was of 12 frequency levels starting from .25 to 3 Hz. The duration of the ground motions
was taken as 5s and damping of RC buildings was assumed to be 5%.
The study was nonlinear dynamic analysis of the models using ETABS 2013. Natural
frequency, interstory drift ratio and time passed before collapse were considered to
analyze the response of the RC frames. The UBC limitation on drift ratio for long period
(≥.7s) structures is .02. The structures were assumed to fail at this drift ratio.
After performing time history analysis, behaviors of the structures are compared. It was
found that when subjected to ground motion infilled frames perform best. Strength of
infill has effect on the response of frames under seismic loading and also on the natural
frequencies of the frames. Completely infilled frames with higher strength infill performed
better. Structures with higher number of story were found to sustain seismic loading for
longer duration before failure. The response of soft story and infilled frames (12 and 15
story buildings) were found to be close if weak infills are used. When subjected to ground
motions, frames were vulnerable to frequency level up to 1.5 Hz.
infilled frames were considered for model in this study. Each frame was further
considered as 6, 9, 12 and 15 story buildings. Soft story and infilled frames were provided
with two types of masonry infill (Em = 1875 and 5625 N/mm2). Frames were subjected to
harmonic ground motions of peak ground acceleration 1, 2 and 3 m/s2. Each acceleration
was of 12 frequency levels starting from .25 to 3 Hz. The duration of the ground motions
was taken as 5s and damping of RC buildings was assumed to be 5%.
The study was nonlinear dynamic analysis of the models using ETABS 2013. Natural
frequency, interstory drift ratio and time passed before collapse were considered to
analyze the response of the RC frames. The UBC limitation on drift ratio for long period
(≥.7s) structures is .02. The structures were assumed to fail at this drift ratio.
After performing time history analysis, behaviors of the structures are compared. It was
found that when subjected to ground motion infilled frames perform best. Strength of
infill has effect on the response of frames under seismic loading and also on the natural
frequencies of the frames. Completely infilled frames with higher strength infill performed
better. Structures with higher number of story were found to sustain seismic loading for
longer duration before failure. The response of soft story and infilled frames (12 and 15
story buildings) were found to be close if weak infills are used. When subjected to ground
motions, frames were vulnerable to frequency level up to 1.5 Hz.