纵向碰撞下FPS隔震曲线桥地震响应分析

Analysis of Seismic Response of FPS Isolated Curved Bridge with Longitudinal Collision

本文结合某曲线桥工程,研究相邻联纵向碰撞对FPS隔震曲线桥地震响应的影响。文中选择桥梁设计半径和主梁跨度为参数,利用反应谱进行单段直梁法、梁格法和多段直梁法建模适用范围的探究。并根据上述结论建立考虑与不考虑碰撞的FPS曲线桥以及考虑碰撞的板式橡胶曲线桥模型,进行对比分析。结果表明,多维地震作用输入下,在跨长不变而曲率半径增大时,3种模拟方法差值逐渐减小,梁格法最优,多段直梁法误差率均在10%之内,单段直梁法存在满足精度要求的临界跨曲比。此外,碰撞可增大装有FPS支座的曲线桥中跨桥墩地震响应,而对边跨桥墩地震响应几乎无影响。建议在实际工程中,将FPS支座用于曲线桥边跨桥墩。

Simulation models are established for investigations of FPS seismic response characteristics,which is related to the a practical curve bridge. Firstly,the design radius and span length are chosen for the variable parameters,using response spectrum as the method in order to find out the suitable conditions of single beam,beam-grillage and straight lines under the action of earthquake. Then on the basis of above conclusion,FPS curve bridge numerical models considering collision,without collision,and considering laminated rubber bearing and collision are established,and the results are compared and analyzed. The results show that,under bidirectional earthquake,when the span length is aptotic and radius of curvature increases,the difference of three simulation methods is reduced.Beam-grillage is optimal,single beam＇s error rate is below 10%,straight lines error exists＂critical L / R＂. In addition,collision can increase the seismic response of middle piers of bridge,while has no effect on the seismic response of side piers of bridges. In practical engineering,the FPS bearing should be used on side piers of bridges.