Seismic retrofitting of precast concrete beam-column joints using self-centering friction damper

Experimental results show that beam-column joints have a considerable effect on the seismic behavior of precast concrete buildings and the most damages are in this area. Local retrofitting precast concrete beam-column joints with selfcentering friction dampers is an effective method for seismic strengthening in the exterior and interior beam-column joints. This study evaluated the seismic performance of retrofitted precast concrete beam-column joints using self-centering friction damper. For this goal, a nonlinear model is proposed to simulate the cycle behavior of the retrofitted joints models in OpenSees software framework that are calibrated by experimental specimens. Then, the efficiency of using self-centering friction damper on the seismic behavior of the precast building damaged during the Bojnord earthquake 13 May 2017 in Iran (M_W 5.4), is investigated. The results show the capability of the self-centering friction damper in enhancing the energy dissipation, stiffness and strength of the precast concrete beam-column joints. Also, the incremental dynamic analysis (IDA) approach was used to determine the fragility curves of the retrofitted precast building. The results show that the haunches retrofitting method increases the mean acceleration values for all damage limit states remarkably.