Seismic fragility of cushioning high-speed railway bridges

The FE model of a high-speed isolated railway bridge with E-shape steel damping devices was established, in which the impact of the railway track was taken into account, and 100 strong ground motions were selected from PEER considering the soil conditions to conduct nonlinear time-history analysis of the structure. Four critical states were defined for each member according to the failure criterion based on displacement, traditional reliability method was used to obtain the seismic fragility curves of bridge piers, abutments and bearings. The results show that the seismic fragility of different bridge piers and bearings under each critical state are significantly different, bearings are more vulnerable for seismic damages than the bridge piers and abutments, the seismic isolation design for railway bridges with piers of different height should be performed on the basis of the longitudinal stiffness of each bridge piers.