To evaluate the seismic performance of large rupture strain fiber reinforced polymer (LRS FRP)-reinforced bridges under earthquake action

this paper takes a typical three-span continuous girder bridge as the analytical model. There are few studies on LRS FRP-confined concrete models under cyclic axial compression

which limits the seismic analysis of LRS FRP-reinforced bridges. Therefore

the simplified LRS FRP-confined concrete model under cyclic axial compression proposed by the authors’ research group was introduced. According to the simplified model

the seismic fragility of the continuous girder bridge before and after LRS FRP strengthening was analyzed based on the seismic fragility analysis theory and incremental dynamic analysis (IDA) method using OpenSees platform. Results show that the bridge columns were mainly in an undamaged linear elastic state under slight damage and moderate damage

and LRS FRP reinforcement had little effect on the seismic fragility. In extensive damage and complete collapse states

the exceedance probability of damage of unreinforced bridge was significantly greater than that of LRS FRP-reinforced bridge. The proposed simplified LRS FRP-confined concrete model can provide reference for seismic analysis of LRS FRP-reinforced bridges.