Estimation of collapse capacity and collapse fragility using modal pushover analysis

Abstract

Structural collapse during earthquakes causes massive loss of economy and human lives. For protecting structures from collapse, accurate estimation of collapse intensity and collapse fragility is very important. To estimate the collapse intensity of a structure, incremental dynamic analysis (IDA) can be used. The IDA of practical structures, however, is computationally extremely demanding since the IDA requires repeated nonlinear response history analyses (RHA) of a structure for an ensemble of ground motions. This study develops a simple and accurate procedure for estimating the collapse intensity and collapse fragility of a structure using modal pushover analyses (MPA) and an empirical equation of collapse strength ratios.