Author : Vikas Yachawad 1
Date of Publication :24th January 2018
Abstract: From the past some decades we dealt with several earthquakes, which proved that the influence of the effects induced due to the earthquake is severe in the irregular structure. As behavior and instance of these natural hazards are unpredictable, we can just design the structure which can resist the effects induced by them hence several codes have been developed to differentiate these type of vertical and horizontal irregularities. Some critical measure also given in these codes to deal with these type of irregularities. The objective of this study is to carry out the seismic analysis of vertically irregular buildings as per IS1893:2016 and compare the effects of those irregularities with the analysis results of the regular building structure. A regular and three stepped building with a different configuration has been taken for the analysis. Seismic analysis of those buildings has been carried out by using equivalent static analysis (ESA) and response spectrum analysis (RSA). Use of magnification factor has been taken into consideration to scale up the response spectrum analysis results up to the results of an equivalent static analysis. Regularity index for an irregular building has been calculated to compare modification in the time period of same irregular building over code specified time period and thereby modification in spectral acceleration and base shear. First mode participation factor and time period of an irregular building are found to be lesser than the regular building whereas the base shear of an irregular building is higher than the regular building.
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