基于反应位移法的复杂软土盾构隧道横断面抗震分析

Seismic Transverse Analysis of Shield Tunnels in Complex Soft Soil through Response Deformation Method

摘要:

采用反应位移法，利用ABAQUS软件建立梁-弹簧有限元模型，进行复杂软土场地中盾构隧道横断面抗震分析，并结合天津滨海Z2线软土盾构隧道进行计算。研究表明，在地震作用下，最大弯矩值和剪力值一般出现在拱肩位置，最大轴力值一般出现在拱腰附近；处于复杂地层附近的隧道结构内力值较大，应加强该位置处的抗震构造措施或在选线时尽量避免复杂场地。本文对复杂软土场地中盾构隧道横断面抗震设计具有一定参考价值。

Abstract:

A beam-spring finite element model is established using ABAQUS to conduct seismic transverse analysis of shield tunnels in soft soils through response deformation method. Model calculation is conducted on Tianjin Binhai metro line Z2 project. Result shows that under the action of earthquake, the maximum bending moment and shear force generally appear at the shoulder of the arch and the maximum axial force appears near the waist of the arch. The internal force values of the tunnel structure near the complicated soil layer are large, so seismic construction measures at these positions should be strengthened or complicated sites should be avoided in line selection. This study is of certain value for seismic transverse design of shield tunnels in complex soft soil areas.