Seismic Vulnerability Analysis of Isolation Bearing for Curved Continuous Girder Bridge

Abstract

Based on a curved continuous girder bridge project, this thesis employed the seismic vulnerability method to analyze the isolation bearings which were usually considered as the fragile member of bridge. Laminates rubber bearing (LNB) was selected for analysis. The mechanical model and damage index are determined. The vulnerability curve of the bearings could be formed with the traditional reliability method based on logarithm linear regression analysis. Determined the mechanical model and damage index of the bearing, and the nonlinear dynamic analysis model of the bridge is established. Selected ten records of earthquake and amplitude modulated according to the requirements of incremental dynamic analysis method. Then, respectively formed the bridge - ground motion random sample with the bridge random sampleThe analysis results indicated that the position of isolation bearings and the direction of seismic inputting had different level effect on damage probability of bearings.