软岩隧道的围岩变形计算

The Calculation of Deformation of Soft Rock Around Tunnels

文献[6]在考虑软岩的剪胀、蠕变和非线性破坏准则等影响后,推导隧道的围岩变形表达式.在此基础上,考虑软岩的塑性大变形特性后,分别根据相关联与非关联流动法则,推导出圆形隧道位移解.通过计算得出:在软弱的围岩或土中,剪胀角的大小对隧道塑性区软岩位移影响很大.

To study the effects introduced by the assumption of a linear MohrCoulomb yield criterion on displacement around tunnels,this paper discusses the problem by using a nonlinear yield criterion and large deformation theory.The radial displacements expressions are derived around a tunnel in uniform isotropic soft rock or soil by using an associated and a nonassociated flow rule.The influence of dilatancy and creep of rock is considered in the expressions.From the numerical results,it is shown that the dilatancy angle plays an important role in controlling the radial displacement around tunnels in plastic zone.