FSD耦合模型在多孔水压致裂试验中的应用

运用以渗流、应力、损伤耦合模型(FSD-Model)为基础的岩石破裂过程分析(RFPA)系统，对非对称孔隙压力梯度下非均匀岩石多孔水压致裂过程中的裂缝扩展模式进行了数值模拟研究。数值模拟再现了水压致裂过程中岩石由细观微破裂到宏观破坏的演化过程，并且与试验结果表现出了较好的一致性。研究结果表明，水压致裂过程中裂纹的扩展模式和压裂压力都受到裂纹尖端局部孔隙水压力大小和宏观上孔隙水压梯度分布的影响，裂纹总是向高孔隙水压力的区域扩展，并且压裂压力随着局部孔隙水压力的增大而降低。模拟的研究结果对实际的压裂施工具有一定的参考价值。

Application of FSD Coupling Model to the Test of Multiple Hydraulic Fracturing

By using the Rock Failure Process and Analysis code (RFPA),which is based on the flow-stress- damage (FSD) coupling model,the behavior of multiple hydraulic fractures in the homogeneous rocks is simulated and investigated. The simulation results reflect macroscopic failure evolution process induced by microscopic fracture subjected to hydraulic loading,which agrees well with the experimental results. Based on the simulation research,it is pointed out that the pore pressure magnitude on a local scale around crack tip and the distribution of pore pressure on a global scale may both affect the behaviors of cracks and fractured pressure. The fractures always propagate towards the regions with higher local pore pressure and the fracture pressure decreases with the increment of local pore pressure. The research provides valuable guidance to the designers of hydraulic fracturing engineering.