基于地震易损性的双柱薄壁墩连续刚构桥的抗震性能分析OA

The seismic performance of continuous rigid-frame bridges is significantly influenced by the stiffness of twin-column thin-walled piers.In this study,a finite element model of a continuous rigid-frame bridge featuring twin-column thin-walled piers was initially developed by OpenSees.Based on the existing quasi-static test results of twin-column thin-walled piers,the hysteresis curve and skeleton curve obtained from the test and finite element were compared to verify the accuracy of the finite element model.Then,the damage indexes of bridge piers were defined and quantified through section performance analysis according to the concept of ductile seismic design,and a seismic vulnerability model for the main bridge of a twin-column thin-walled pier rigid frame bridge was established.Finally,the effects of wall thickness,column spacing,pier height on the seismic performance of continuous rigid frame bridges were evaluated based on the seismic vulnerability analysis method.The results indicate that an increase in the spacing between twin columns and the wall thickness of individual columns can enhance the seismic performance of the bridge to some extent.However,this improvement effect is limited,and the optimal ratio of the spacing between twin-columns to the wall thickness of individual columns varies at different pier heights.For piers not exceeding 90 meters in height,to achieve optimal seismic performance while maintaining material economy,a ratio of 10.5 for the spacing between twin-columns to the wall thickness of individual columns is recommended.