考虑横、纵向不规则的大型盾构隧道横通道抗震分析

Anti-seismic Analysis of Cross Connection in Large Shield Tunnel with Transverse and Longitudinal Irregularities

杭州环城北路两条盾构隧道之间拟设置横向疏散通道,主隧道与横通道无论是结构型式还是结构尺寸均有巨大差异,尤其是在双线不等高、管片纵向不能同步推进的不规则情况下,地震时可能会进一步加剧在主隧道与横通道接口部位的局部附加应力和变形。为了掌握地震时横通道和主隧道相连接部位的受力情况,检验和改进结构设计,采用三维模型对其进行了动力学数值模拟计算,包括了横、纵向地震激励。计算结果表明,结构内力及相对变形均较大,根据分析结果,结合工程功能特点,建议取消该横通道,改为纵向逃生救援方案,辅以两端工作井设置车行横通道解决车辆沟通问题。

In the early design stage of Hangzhou Ring Road, horizontal cross duct was intend to be set up between two shield tunnels. There were huge differences between the adit and main tunnel both in structure style and dimensions, especially in situation of different height and longitudinal not synchronous propulsion of segments in two tunnels. The additional stresses and deformations in the interface between the main tunnel and the cross channel may be further intensified under earthquake. 3D model was established to study the inner force near the cross duct under earthquake, including horizontal and vertical seismic excitation, and then to optimize design. The calculation results show that the internal force and deformation are relatively large. According to the analysis results, combined with the engineering features, the proposal is to cancle the cross passage, and change it to longitudinal escape and rescue scheme, while setting car cross channel in the work well to solve the vehicle communication problems.