Research Articles | Challenge Journal of Concrete Research Letters

Seismic Behaviour of Multistorey RC Frames with vertical Mass Irregularities

V K Sehgal, B Saini

Abstract


The buildings with mass irregularity behave differently as compared to regular buildings. In the present study, a parameter called mass irregularity index has been proposed to quantify the mass irregularity. The proposed factor depends mainly upon magnitude and location of mass irregularity. Further the present study aims to modify the expression of time period proposed by IS 1893:2002 and relation between mass irregularity coefficient and time period has been evaluated. For present study a family of 108 frames with mass irregularity have been modelled and analyzed by time history analysis. The proposed expression for time period has been validated for buildings with mass irregularity.

Keywords


mass irregularity; vertical irregularity; irregularity in buildings; fundamental time period

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References


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