岩石流变扰动效应三轴压缩试验研究

The main part of deformation of surrounding rock in soft rock roadway of deep mine is rheology when the stress status of surrounding rock is in the range of limit neighbor of rock strength. And the important component of rheology is disturbance deformation. So, it is important to study the rheological properties of rock under the condition of disturbance load and build the disturbing rheological theory, which has an important practical engineering value for the soft rock roadway supporting. This research employs the testing machine for rock rheological perturbation effect and electro-hydraulic servo triaxial test system to study the range of limit neighbor of rock strength of the rock that is applied by triaxial compression and the relationship between disturbance creep of rock and disturbing load, by which the constitutive model of rock under triaxial compression and perturbation effect can be built. Combining the constitutive model and FLAC3D numerical software, the numerical computing method for the disturbance deformation of rock is set up. This study will expand the rock disturbing rheological theory, which can provide the theoretic basis and guide for soft rock supporting.

在深井软岩条件下，巷道围岩应力状态处于岩石强度极限邻域内，变形主要是流变，其中扰动变形是其重要的组成部分。因此，研究岩石在扰动载荷作用下的流变力学特性，建立岩石流变扰动理论，对深井软岩支护具有重要的工程实用价值。本项目拟采用岩石流变及扰动效应实验仪和电液伺服岩石三轴试验系统，试验研究岩石介质在三轴压缩流变状态下易于受扰动作用而产生蠕变的强度极限邻域范围；试验研究三轴压缩条件下岩石扰动蠕变与扰动载荷的关系，构建岩石三轴压缩流变扰动效应的本构模型；将岩石三轴压缩流变扰动效应本构模型与FLAC3D数值软件集成，建立岩石三轴压缩流变扰动效应数值计算方法。本项目的研究成果可以丰富岩石流变扰动理论，为深井软岩支护提供理论依据和指导。

在深部开采条件下，围岩应力状态已接近岩石强度极限，很容易因掘进和开采扰动作用而产生大变形。本项目通过岩石流变及其扰动效应试验，研究岩石在单轴和三轴条件下的流变扰动特性。研发了RRTS-Ⅲ型岩石流变扰动效应三轴试验系统；利用研发的试验系统进行了单轴条件下的岩石流变扰动效应实验，揭示了岩石在恒定轴向荷载下，处于强度极限邻域内和强度极限邻域外的流变扰动效应规律，并根据实验结果，绘制了不同流变阶段的累计扰动变形量—累积扰动能量曲线，结合岩石流变扰动的影响因素，在流变扰动曲线的基础上建立了岩石流变扰动本构方程；利用红砂岩进行了三轴条件下的岩石流变扰动效应实验，确定出了三轴应力条件下岩石易于产生扰动流变的强度极限邻域范围，通过岩石三轴压缩流变扰动试验，构建出了岩石三轴压缩流变扰动效应本构模型。本项目研究成果拓展了岩石流变扰动效应理论，对深井软岩支护具有重要的工程实用价值。