Energy based seismic risk assessment for steel concentric braced frames

In this study, displacement profile for direct displacement based design method (DDBD), an energy based damage index and fragility curves for steel concentric braced frames (CBFs) have been developed. Twelve CBFs with different characteristics subjected to thirty different seismic intensities are scoped. DDBD has been adopted in this study to ensure authentic performance of CBFs throughout seismic analyses. Non-linear time history analysis, incremental dynamic analysis and continuous wavelet transform are implemented to develop an energy based damage index. The proposed damage model compared with drift based damage index. Finally, seismic fragilities for CBFs are developed for different performance levels.