侧压力系数对节理岩体隧道稳定性的影响

Impact of lateral pressure coefficient on stability of tunnel in jointed rock mass

为研究侧压力系数对节理岩体隧道稳定性的影响,利用ABAQUS有限元软件建立了节理岩体隧道模型,分析了不同的侧压力系数和倾角节理对隧道围岩稳定性的影响,研究了围岩变形规律、围岩应力分布、塑性区域分布及围岩破坏时塑性流动规律。研究结果表明:随着侧压力系数的不断增加,围岩竖向位移、最大主应力、最大等效塑性应变均呈现先减小后增大的趋势,围岩应力集中更显著;当节理倾角一定时,随着侧压力系数的不断增加,安全系数先增加后减小;当侧压力系数一定时,随着节理倾角的增加,安全系数先减小后增大。本研究结果以期为节理岩体隧道的设计与施工提供参考。

In order to study the impact of lateral pressure coefficient on the stability of tunnel in jointed rock mass,the finite element software ABAQUS was used to establish the tunnel model in jointed rock mass,the impact of lateral pressure coefficient and joints dip angle on the stability of surrounding rock was analysed.The deformation law of surrounding rock,the distribution of stress and plastic zone,and the failure law of surrounding rock were investigated detailedly.The results show that,with the increase of lateral pressure coefficient,the vertical displacement,the maximum principal stress and the maximum equivalent plastic strain of surrounding rock decreased firstly,and then increased.When the dip angle of joint was the same,the safety coefficient firstly increased and then decreased with the increase of the lateral pressure coefficient.When the lateral pressure coefficient was the same,the safety coefficient firstly decreased and then increased with the increase of the dip angle of the joints.The conclusions can provide a useful reference for the design and construction of tunnel in jointed rock mass.