基于参数折减法的绿片岩围岩稳定性分析

Stability Analysis of Chlorite Schist Surrounding Rock Based on Parameters Reduction

绿泥石片岩隧洞相比硬岩隧洞更容易受外界水环境影响发生失稳破坏.绿泥石片岩作为一种典型软岩,水的作用对岩体力学性能影响明显,容易发生软化效应,影响围岩稳定.本文以某引水隧洞工程为例,基于软岩隧洞围岩单参数敏感性分析,采用多参数折减系数法模拟软化区域,应用三维有限元对绿泥石片岩洞段开展软化区域和未软化区域的围岩及结构稳定分析.计算成果与现场实测数据对比结果显示,计算值与实测值吻合度较好,软化区域的围岩及结构受力情况明显高于未软化区域,仍符合设计要求,满足工程安全需要.

The soft rock tunnels are more susceptible to the environmental water than hard rock tunnel to occur stability failure. As a kind of typical soft rock, the mechanical properties of chlorite schist is so obviously influenced by the role of water that the rock occurs softening effect to affect the stability of surrounding rock. Based on a diversion tunnel project, this paper uses the method of parameters reduction coefficient to simulate softening area, and uses the three-dimensional finite elements to analyze surrounding rock and structure. The comparison between calculation results and the field measured data show that the calculated values and measured values coincide well; and the forcing conditions of surrounding rock and structure in softening area are obviously higher than ones in the rest area, but they meet the design requirements and the engineering safety.