近断层高速铁路连续梁桥减隔震研究

Research on Seismic Isolation and Mitigation of Continuous Beam Bridges for High-Speed Railways near Faults

摘要:

近年来我国在地震带分布密集地区建设了高速铁路桥梁。邻近断层高速铁路桥梁有遭受强地震破坏的风险。对近断层地震动作用下确定合适的高铁连续梁桥抗震体系，已成为当前强震区近断层高速铁路桥梁抗震设计亟须解决的问题。分析罕遇地震作用下桥梁的非线性时程，讨论了双曲面球型减隔震支座的单独使用，及其与黏滞阻尼器联合应用方案，对近活动断层高速铁路连续梁桥进行抗震设计。发现单独使用双曲面球型减隔震支座的桥梁内力会降低，但墩梁相对位移超限；双曲面球型减隔震支座与黏滞阻尼器联合应用，梁墩相对位移值大大减小。同时，设置黏滞阻尼器后，墩身内力总体上变化不大，满足规范要求。

Abstract:

In recent years, high-speed railway bridges have been built in the areas with dense seismic zones in China. High-speed railway bridges near faults have a high seismic risk. The determination of the appropriate seismic system of continuous beam bridges for high-speed railway under the action of near-fault ground motion has become an urgent problem to be solved in the seismic design of near-fault high-speed railway bridges in strong earthquake areas. The nonlinear time-history analysis of the bridge under the rare earthquakes is conducted. The single use of hyperboloid spherical seismic isolation bearing and its combined application with viscous damper are discussed. The seismic design of continuous beam bridges for high-speed railway near active fault is carried out. It is found that the internal force of the bridge using the hyperboloid spherical seismic isolation bearing alone will be reduced, but the relative displacement of the beam piers exceeds the limit. The joint application of hyperboloid spherical seismic isolation bearing and viscous damper will make the relative displacement of beam piers greatly reduced. At the same time, after setting the viscous damper, the internal force of the pier body does not change much on the whole, which meets the requirements of the specification.