具有不同倾角层状结构面岩体中隧道稳定性数值分析

通过引入细观层次的微元体,采用损伤力学和统计理论的单元本构模型,利用岩石破裂过程分析软件RFPA(realisticfailureprocessanalysis),对具有不同倾角层状软弱结构面岩体中隧道的变形破坏特征、隧道周边关键部位的位移进行了分析·结果表明,层状结构面倾角大小对围岩的破坏失稳模式有显著的影响·随结构面倾角的增大,隧道周边应力分布的非对称性逐渐增强,从而造成了破坏模式的非对称性·结构面倾角增大对边墙的受力有不利影响·这对于进一步深入理解具有软弱结构面中隧道破坏失稳机理并采取有效的加固措施等具有理论和实践意义·

Numerical Stability Analysis of Surrounding Rock Mass Layered by Structural Planes with Different Obliquities

The RFPA (realistic failure process analysis) software is used to analyze the deformation/failure of a tunnel passing through the rock mass with incompetent laminar structural planes at different obliquities and the displacement of the key points around the tunnel, with microdimensional elements introduced in combination with the elementary constitution model based on damage mechanics and statistics. The results show that the degree of obliquities of laminar structural plane affects obviously the destabilization/failure mode of surrounding rock. The peripheral stress distribution around tunnel is asymmetrized gradually with the increasing obliquity and, eventually, the asymmetry of failure mode takes place. So, the increase in obliquity is disadvantageous to side wall. It is theoretically and practically of importance to understanding further the destabilization/failure mechanism of the tunnel passing through incompetent structural planes of rock mass and the effective measures to be taken for reinforcement.