高速铁路连续梁桥近断层地震易损性分析

Vulnerability analysis of the continuous high-speed railway bridge under near-fault earthquake

为研究近断层地震下高速铁路普通桥梁以及减隔震桥梁的抗震性能,本文应用增量动力分析(IDA)方法,选取墩顶位移作为连续梁桥的损伤量化指标对高速铁路普通连续梁桥和减隔震连续梁桥进行了近断层地震易损性分析。结果表明:同一地震强度下,近断层地震比远场地震更具破坏性,特别是滑冲效应的近断层地震危害性更强,即在进行抗震设计时应将近断层地震的特点纳入考虑;所提出的新型减隔震支座能够有效地减少高速铁路桥梁的地震响应,保障高速铁路桥梁的地震安全性。

The incremental dynamic analysis(IDA) method is used to research the aseismic performance and seismic isolation of high-speed railway bridges under near-fault earthquake. Moreover, the pier top displacement is selected as damage quantitative indicator for bridge vulnerability analysis. The results show that under the same earthquake intensity, the near-fault earthquake is more destructive than the far-field earthquake, especially the near-fault earthquake with fling-step effect, which means that the characteristics of near-fault earthquake should be taken into account in seismic design;and that the new isolation bearing can effectively reduce the seismic response of high-speed railway bridges and enhance the seismic safety of high-speed railway bridges.