PERFORMANCE-BASED SEISMIC FRAGILITY ANALYSIS OF RC FRAME STRUCTURES

The traditional research of structural vulnerability of RC structures mostly focuses on seismic intensity or peak ground acceleration(PGA).The selection of ground motions did not considered the difference between near-field and far-field earthquakes,and the research on building construction is less.Therefore,comprehensively considering the peak ground acceleration and damping ratio of 5% of the spectral acceleration,considering the different natures of near-field and far-field ground motions,fragility analysis on some RC frame structures was did.Four ultimate damage states for entire structure were defined,and based on the definition,a method for solving the limit values of the four performance levels was put forward.Finally,based on the results of incremental dynamic analysis(IDA),the performance-based seismic fragility analysis was carried out using this method,and fragility curves were derived to assess and compare the seismic performances under different IM parameters and different ground motions.According to the actual seismic demand of the structure,it can determine the damage states from the sense of probability,and provide a reference for future seismic damage prediction.