RESEARCH ON SEISMIC FRAGILITY OF REINFORCED CONCRETE FRAMES CONSIDERING A BEAM-COLUMN JOINT MODEL

Beam-column joints have considerable influence on the seismic mechanical performance of reinforced concrete frame structures. There has been a lack of investigation in the application scope of joint simulation based on the rigid joint assumption and the macro-flexible model. The seismic fragility analysis is able to, in a probability sense, to describe the seismic performance of reinforced concrete frame structures, and provide theoretical foundation and technological support when handling beam-column joints. Therefore, by adopting the duel-frequency control method to select the ground motion record, and by defining four different damage states to investigate the performance level, the seismic fragility analysis was conducted with the incremental dynamic analysis method on OpenSees to obtain the exceedance probability for three reinforced concrete frames with different numbers of stories. The results suggest the seismic performance evaluation with the rigid joint assumption is applicable when the structure is designed abide by the national seismic design code and is subjected to frequent earthquakes. Otherwise, the seismic performance evaluation for reinforced concrete frames should consider the deformation of beam-column joints.