深埋绿泥石片岩变形特征及稳定性分析

根据锦屏二级水电站绿泥石片岩的特点，在同一断面综合采用变形、应力和钻孔电视多种监测手段，分析围岩内部的力学状态。为了更加深入地认识绿泥石片岩的工程力学特性及其对变形破坏机制的影响，开展单轴和三轴压缩试验、灌浆渗透性试验和三轴流变试验，揭示绿泥石片岩变形、破坏和失稳的多方面原因，并为支护措施的确定提供参考意见。绿片岩洞段的围岩稳定主要取决于衬砌结构能否抵挡流变和遇水软化2种作用导致的挤压效应，通过引入软化系数和退化的Burgers流变模型，从衬砌结构的受力角度对围岩稳定性进行评价，数值计算结果表明衬砌结构具有相当高的安全裕度。

DEFORMATION BEHAVIOR AND STABILITY ANALYSIS OF DEEP CHLORITE SCHIST

According to the characteristics of chlorite schist in Jinping II hydropower station，in the same section，multiple monitoring means including the deformation，stress and borehole TV were adopted to analyze the internal mechanical state of surrounding rock. In order to understand the engineering mechanical properties of chlorite schist and its impact on the deformation failure mechanism，uniaxial and triaxial compression tests，grouting penetration test and triaxial rheological test were carried out. And the test results revealed many factors of deformation，instability and destruction of chlorite schist，and provided reference for determination of supporting measures. The stability of chlorite schist depends mainly on whether the lining structure can resist the squeezing effects caused by rheology and water softening. By introducing softening coefficient and Burgers rheological model，the surrounding rock stability from the viewpoint of the force of the lining structure was evaluated. The results of numerical calculation show that the lining structure is in high safety redundancy.