IDA-based seismic fragility analysis of a complex high-rise structure

Incremental Dynamic Analysis(IDA) is a parametric analysis method that emerges in several different forms to estimate more thoroughly structural performance under seismic loads.It involves subjecting a structural model to one(or more) ground motion record(s),each is scaled to multiple levels of intensity,thus producing one(or more) curve(s) of response parameterized versus intensity level and depicting the whole process of the structure from elastic to elastic-plastic until collapse.Seismic fragility analysis brings in fragility curves which are useful tools for showing the probability of structural damage due to earthquake as a function of ground motion indices.Results of IDA provide the data needed for producing fragility curves.In this paper IDA is combined with seismic fragility analysis and the IDA-based seismic fragility analysis method is proposed.A complex high-rise structure is taken as an example to illustrate the procedure.The probabilities of five limit states are exceeded for three given ground motion intensity levels,which are estimated,respectively.