基于各向异性摩擦摆支座的大跨度混凝土混合连续梁减震性能研究

Study on Seismic Mitigation Performance of Long-Span Concrete Composite Continuous Beam Bridge Based on Anisotropic Friction Pendulum Bearings

摘要:

以京杭运河特大桥三跨混合连续梁桥为工程背景，采用有限元方法建立全桥精细化数值模型，针对桥梁在地震作用下的动力响应展开研究。通过设置无减隔震措施与各向异性摩擦摆支座2种对比方案，系统分析不同工况下桥梁结构的动力特性与地震反应差异，从纵桥向与横桥向双维度揭示各向异性摩擦摆支座的减震控制效果。研究表明，各向异性摩擦摆支座能够有效调节桥梁自振特性，显著减小关键截面内力与墩顶位移，提升结构整体抗震性能。该减震措施兼具技术可行性与经济合理性，能够在强震作用下保障桥梁受力安全并维持使用功能，可为同类大跨度混凝土混合连续梁桥的抗震设计与减隔震优化提供理论依据和工程参考。

Abstract:

Based on the three-span composite continuous beam bridge of the Beijing-Hangzhou Grand Canal Bridge, a refined full-bridge numerical model is established by a finite element method to study the dynamic response of the bridge under the action of earthquake. By comparing two schemes of one without seismic isolation measures and the other with anisotropic friction pendulum bearings, the dynamic properties and seismic response difference of bridge structures under the different working conditions are systematically analyzed, and the seismic control effect of anisotropic friction pendulum bearings is revealed from the two dimensions of longitudinal and transverse bridge directions. The research result shows that the anisotropic friction pendulum bearings can effectively adjust the natural vibration characteristics of the bridge, remarkably reduce the internal forces of critical sections and the displacement of pier tops, and enhance the overall seismic performance of the structure. The proposed seismic control measure has the technical feasibility and economic rationality, can guarantee the stress safety and maintain the using function of the bridge under the effect of a strong earthquake, and can provide a theoretical basis and engineering reference for the seismic design and isolation optimization of similar long-span concrete composite continuous beam bridges.