岩体结构面剪切流变试验及模型参数反演分析

针对锦屏二级水电站地下洞室群围岩富含节理的实际情况，采用弱面直剪流变仪对组成隧洞围岩的主要岩样（板岩、大理岩）进行了含软弱夹层岩石的剪切流变试验，得出岩石夹层的剪应力-剪切位移时程曲线。通过对岩石夹层试验结果的分析，得出了岩石的长期强度参数，与快剪试验获得抗剪强度参数相比较发现长期抗剪强度参数有所降低，且凝聚力对剪切流变特性的影响略高于内摩擦系数。最后通过对6种模型的拟合分析，得出了适合岩石夹层的标准线性体流变模型，在此基础上通过反演分析得到了岩石夹层标准线性体黏弹-塑性剪切流变模型，并反演了该模型的参数。

Shear rheological experiment on rock mass discontinuities and back analysis of model parameters

The subsurface rock masses for Jinping Second Stage Hydropower Station caves features with abundant joints. A shear rheological experiment was carried out on the weak rock interlayer masses i.e. slate and marble, with respect to their shearing behaviors. A weak-surface direct shear rheological apparatus was employed to fulfill the experiment. Time domain related shear stress-shear displacement curves of the rock masses were obtained. Long-term shear strength parameters of weak rock interlayer samples were found that decreased compared to those given from rapid shear tests. Rock cohesion is more effective than its internal friction coefficient in affecting shear rheological behaviors. A standard linear viscoelasto-plastic rheological model is proposed by simulating testing results on six general shear rheological models. The proposed model is suitable to describe the shear rheological behaviors of the weak rock interlayer masses. Model parameters are gained through back analysis.