温度-渗流-应力耦合作用下岩石损伤及声发射特征研究

深部地下围岩常常处于复杂的地质环境下，这些复杂的地质环境造就了岩石多变的物理力学行为，本文对取自某矿井的黏土岩开展温度-渗流-应力耦合特性及声发射试验研究，对黏土岩在不同地质环境下的变形特征、渗透特性、损伤及声发射演化特征进行分析。研究结果表明:温度和围压对试件的变形具有明显的损伤劣化和抑制作用，温度越高，围压越大，试件逐渐由脆性断裂向脆延性破坏转变；渗透率的变化对应于岩石体积变化出现降低-平衡-上升-回落四个阶段，体变和环向应变突变点为渗透性加速增大分界点；高围压和温度作用下，岩石的声发射呈高能高幅值特征，渐变特征不明显，最活跃值越滞后，低温和低围压下，声发射具有明显的渐变特征，最大值出现在峰值附近；同等围压下，渗透损伤值随温度的升高而增加，围压越大，渗透损伤值越小，温度越高围压越大，损伤发展越均匀。

A study of the rock damage and AE characteristics under the coupling of temperature,seepage and stress

Rocks in the deep subsurface are often in a complex geological environment, and physical and mechanical behavior of the complex geological environment makes the rocks multivariate. Experimental research for the clay rocks from a mine on the thermo-hydro-mechanical coupling characteristics and acoustic emission is conducted, and the characteristics of deformation, infiltration, damage and acoustic emission of the clay rocks in different geological environments are analyzed. The results show that temperature and confining pressure have obvious damage degradation and inhibition of deformation for the specimen, and the higher the temperature, the greater the confining pressure is, and the specimen are gradually from brittle fracture to brittle ductile fracture transition. The corresponding Yu Yanshi volume changes with the change in permeability, resulting in four stages of “reduction-balance-increase-fall”. The volume change and mutation point to the ring strain correspond to the permeability accelerated boundary. Under the high confining pressure and temperature, the AE is characterized by “high amplitude”, and the gradient feature is not obvious, and the most active value is lag. Under low temperature and low confining pressure, the acoustic emission has obvious characteristics of the maximum gradient. The maximum value exists in the vicinity of the peak. Under the same confining pressure, the permeability damage value increases with the increasing temperature, and the greater the confining pressure, the less the permeability damage value is. The higher the temperature and the greater the confining pressure, the more uniform the damage is.