Seismic loss risk assessment of RC frame structures designed according to Chinese code

Abstract

According to the PEER probabilistic seismic loss assessment methodology, a structure-level seismic risk assessment method was proposed and implemented for a set of RC frames designed according to Chinese seismic code. These frames were designed for fortification intensities of 6,7 and 8 and classified into 4,6 and 8 stories. Through incremental dynamic time history analysis (IDA), the statistical relationships of the maximum inter-story drift ratio with the seismic spectral acceleration were obtained and used to determine fragility curve for each damage states. The site seismic hazard model was established based on Chinese seismic code, and the probability distribution of each discrete intensity levels was derived. Using loss index from the Chinese standard and Hazus, the structure means annual frequency of collapse, the Expected Annual Financial Loss (EAL) and the Expected Annual Fatalities (EAF) were calculated. The variation trends of these performance metrics with seismic fortification intensities and structure heights were evaluated, and the weaknesses of the current seismic code of China were pointed out. It was concluded that the method proposed in this paper is simple and reliable for practical applications.