越江隧道施工过程的渗流-应力耦合分析

Seepage-stress coupling analysis of river-crossing tunnel excavating

摘要: 隧道开挖和由开挖引起的地下水渗流引起围岩应力重新分布,对隧道围岩的稳定性有重要的影响。本文把隧道开挖过程与渗流场边界的变化紧密联系起来,根据渗流场边界建立了合理的三维有限元分析模型,对规划完成的某越江隧道开挖过程的水-力耦合效应进行了研究,建立了稳定流条件下渗流-应力耦合的基本方程,分析了孔隙水压力随隧道开挖过程的变化规律和水力耦合对围岩位移、应力及支护结构应力的影响程度。数值计算结果表明,渗透系数大的岩层渗流速度和位移受渗流的影响较大,渗流使隧道围岩的位移和应力及支护结构的应力都有较大的增加,水下隧道的设计和施工应该考虑渗流效应。

Abstract: Stress redistribution of surrounding rock induced by tunnel excavation and seepage affects stability of tunnel.Tunnel excavation and seepage field boundary variation were closely connected.Appropriate 3D FEM was established according to seepage field boundary and hydromechanical coupling effect of a planned tunnel excavating was analysed.Seepage-stress coupling equation was established in steady state,pore pressure varying regularity with tunnel excavation and hydromechanical coupling affects to...