水压致裂作用下岩体参数对裂纹扩展影响的数值模拟

应用真实破裂过程分析系统RFPA2D20-Flow，以赋予材料非均匀性为特点，采用有限元计算方法，创建渗流-应力-损伤耦合模型.模拟分析了不同层理角度及不同岩石强度的非均质层理岩体在孔隙水压力作用下的水压致裂过程，描述了这两种岩体参数对拉伸裂缝萌生及扩展的影响趋势.模拟分析结果表明，层理角度和岩石强度对水压致裂作用下层理岩体裂纹扩展模式及岩体稳定性的影响是不可忽略的；随着层理角度的增加，最大主应力及层理弱面分别对压裂裂纹的萌生和扩展起主要控制作用；在同一层理角度条件下，随着岩石强度的减小，层理岩体的稳定性降低，其破裂模式亦产生较大的变化.

Numerical Simulation on Influence of Rockmass Parameters on Fracture Propagation During Hydraulic Fracturing

Hydraulic fracturing process in heterogeneity rockmass with different bedding angles and rock strengths was simulated by using the RFPA^2D2.0-Flow, which, considers the heterogeneous characteristics of rock at meso-scale and establishes coupled seepage-stress-failure model by using finite element method. The numerical results show that the effect of bedding angle and rock strength on fracture initiation, propagation and rockmass stability during the hydraulic fracturing could not be ignored. As bedding angle increases, the maximum principal stress and bedding plane control the fracture pattern of rock specimens respectively. As rock strength decreases, the stability of bedding rockmass which have same bedding angle change greatly.