武汉过江隧道地震响应因素影响分析

运用ANSYS软件，以武汉过江隧道衬砌结构典型地质剖面为例，研究地基土压缩模量、衬砌模量、外径、顶板土层厚度及水深等因素对地震响应的影响，相关参数均来自工程实际，地震荷载考虑EI-centro双向地震作用，得出如下结论：（1）随着地基土压缩模量增大，衬砌同一节点竖向位移和应力最大值逐渐减小；在同一时刻，最大节点位移分布在衬砌顶部，最小节点位移分布在衬砌底部；最大节点应力主要分布在衬砌左右侧壁位置，最小节点应力则分布在左上侧壁位置区域。当土压缩模量大于20MPa后，无论是位移还是应力，其变化幅度减小。（2） 衬砌模量越大，其节点位移减小，而节点应力增大；外径越大，其节点位移较小，而节点应力除拱顶、拱底外逐渐增大，拱顶拱底应力先略微减小然后增大。（3）地基土厚度越大，其节点位移逐渐减小；节点应力则逐渐增大。（4）衬砌上部水深越大，无论是节点位移还是应力均逐渐增大。当水深在10m内时，变化幅度较小；超过10m后，变化幅度增长较快。

Factors influence analysis for seismic response of Wuhan

Factors influence on seismic response of typical geology section of Wuhan cross-river tunnel are studies, which include compress modulus of foundation soil、modulus of lining structure、diameter、top soil thickness and water depth based on software of ANSYS, Pertinent parameters of which are from engineering practice and bilateral seismic actions of EI-Centro earthquake waves are considered. Some conclusions have been obtained： （1） The biggest values of node vertical displacement and stress of lining structure decrease gradually with increasing of compress modulus of foundation soil. At the same moment, the node displacement of lining arch crown is the biggest, which of soffit lining is the least. The maximal equivalent stress of node distributes on lining side wall and the minimal does on top left corner of lining. Change extent of both displacement and stress decreases when soil compress modulus is more than 20MPa.（2） The node displacement is less and the stress is bigger with modulus of lining structure increasing, which becomes less and node stress of all position except lining arch crown and soffit lining becomes bigger with lining diameter augmenting while they firstly decrease and then increase.（3） The node displacement decreases and stress increases by and by when foundation soil thickness becomes larger.（4） Both node displacement and stress become enlarged with the increase of water depth above lining structure. The change rate is smaller within water depth of 10m and bigger when it exceeds 10m.