拉索限位装置对跨断层桥梁地震响应的影响

Effect of Cable Restrainers on Seismic Response of Cross-fault Bridges

摘要:

以一座三跨连续梁桥为工程背景，选择典型的近断层脉冲地震动，应用非一致激励的非线性时程分析方法，对考虑滑冲效应的跨断层桥梁地震响应进行计算，研究不同断层位置的情况下拉索限位器对跨断层桥梁地震响应的影响，并对拉索限位器的自由程和限位刚度进行参数分析。结果表明：应用拉索限位器可以有效地减小跨断层桥梁的位移响应，同时桥墩的受力会有所增加；跨断层桥梁的地震响应对限位器自由程的变化更加敏感。

Abstract:

In this paper,the seismic response of a three-span fault-crossing continuous girder bridge subjected to near-fault pulse-like seismic ground motions is calculated considering the fling-step effect. Typical near-fault pulse-like ground motion records are selected and nonlinear response history analyses are adopted in an asynchronous excitation scenario. The effect of cable restrainers on the seismic response of fault-crossing bridges is investigated under different fault locations. In addition, parametric analyses on lateral restraining displacement and lateral stiffness of the cable restrainer are conducted. Results show that using the cable restrainer can effectively mitigate the displacement response of fault-crossing bridges while it enlarges the pier-bottom moment; seismic responses of a fault-crossing bridge are more sensitive to changes in the lateral restraining displacements of the cable restrainer.