高速铁路曲线连续刚构桥抗震性能研究

Study on Seismic Performance of Curved Continuous Rigid-frame Bridges along High-speed Railway

摘要:

为研究曲线连续刚构桥梁桥墩宽度对抗震设计的影响规律，考虑桩土作用、曲线影响、地震作用对盐泰锡常宜铁路京杭运河特大桥92 m+176 m+92 m曲线连续刚构桥进行有限元分析，对其在多遇地震、设计地震、罕遇地震作用下的抗震性能进行验证。结果表明，增加桥墩宽度（宽高比）能有效提升结构整体刚度，但会引发关键截面内力的显著重分布，桥墩宽高比接近0.11~0.13时，能有效平衡结构刚度需求和内力控制；曲线线形会导致结构出现复杂的空间耦合响应，有必要考虑桩土作用、曲线效应和多方向地震激励建立精细化分析模型，优化桥墩设计。研究成果验证了该桥抗震设计的可靠性，可为同类桥梁抗震设计提供参考。

Abstract:

In order to study the influence of pier width on the seismic design of curved continuous rigid-frame bridges, and considering pile-soil interaction, curve effects and seismic actions, a finite element analysis is conducted on the (92+176+92)-m curved continuous rigid-frame bridge of Beijing-Hangzhou Grand Canal Bridge in Yancheng - Taizhou - Wuxi - Changzhou - Yixing High-speed Railway to verify its seismic performance under the actions of frequent, design-level and rare earthquakes. The results indicate that increasing the pier width (width-to-height ratio) effectively enhances the overall structural stiffness, but will lead to significant redistribution of internal forces in critical sections. When the width-to-height ratio of the pier approaches 0.11~0.13, a balance between structural stiffness requirements and internal force control can be effectively achieved. The curved alignment induces the complex spatial coupling responses of the structures, necessitating the development of refined analysis models that consider the pile-soil interaction, curvature effects and multi-directional seismic excitation to optimize the pier design. The findings validate the reliability of the seismic design for this bridge and can serve as a reference for the seismic design of similar bridges.