Performance-based seismic retrofit of RC structures using concentric braced frames equipped with friction dampers and disc springs

摘要

In this study, concentric braced frame installed with a friction damper-disc-springs is proposed to enhance the seismic performance of RC framed structures. The structural configuration of the retrofit is outlined and the analytical model is explained. A performance-based seismic retrofit procedure combined with a genetic algorithm (GA) optimization is proposed to obtain the optimum design variables of the retrofit. 2D and 3D structural models are used as case studies. The effectiveness of the proposed retrofit is assessed through non-linear timehistory response analysis (NLTHA), fragility analysis, and seismic life cycle cost (LCC) estimation. To ensure that concrete stresses after retrofit are within acceptable limits, finite element method is used. The results show that the proposed retrofit technique is effective in reducing the maximum inter-story drift ratio and in eliminating the residual drift of the model structures significantly. In addition, the probabilities of exceeding different limit states and the total seismic LCC are significantly reduced compared to the un-retrofitted cases.