ABSTRACT
Seismic damage had shown that bearing damage was common in the actual damage of bridge structures. It was considered as the weakest part of seismic performance in bridge structure system. Based on 32m-span simply-supported girder railway bridges in China, considering the mechanical characteristics of two kinds of typical bearings, a precise nonlinear dynamic analysis model was established. The bearing damage index based on the displacement failure criterion was put forward, and then the vulnerability curves of two kinds of bearings under different damage states were formed by traditional reliability probability analysis method. The seismic performance of two kinds of bearings was compared and evaluated from the viewpoint of vulnerability. The results show that the vulnerability of the two kinds of bearings under different damage states is obviously different under earthquake. When the pier is low, the double spherical aseismic bearing has a good isolation effect, which effectively reduces the failure probability of the bearing components under different damage conditions. However, with the pier height increasing, the isolation effect gradually decreases, which indicates that for simply-supported bridges with high piers, the seismic performance of bearings cannot be improved by using it.
