基于应力平衡方程、渗流连续性方程以及改进的Biot有效应力原理，建立了含裂隙可变形饱和多孔介质流-固全耦合问题的控制方程。流体在介质和裂隙中的流动均满足达西定律，得到的非线性全耦合方程不仅反映多孔介质内部物理量的耦合效应，还考虑介质与裂隙之间的耦合作用。扩展有限元法在处理含裂隙问题时具有独特的优势，采用普通有限元和扩展有限元法构建了数值计算体系。在进行空间离散时，介质内部的位移和孔隙压力均采用普通的有限元进行离散；裂隙处的位移模式引入扩展有限元中的两类附加位移函数，以反映裂隙面的位移强不连续性和裂隙端部的应力奇异性；引入孔隙压力加强函数，以体现裂隙法向孔隙压力的弱不连续特征。使用向后差分格式进行时间离散。算例验证了该模型和算法的正确性和有效性，分析了裂隙的存在对流体流动的延迟作用、裂隙中张开位移及孔隙压力等物理量的分布情况，讨论了渗透率、外部流量的改变对计算结果的影响。

Fully coupled governing equations are developed for hydro-mechanical analysis of deforming porous medium with fractures based on the stress balance equation, the seepage continuity equation and the modified Biot effective stress principle. The flow of the fluid within the medium, and fracture satisfies the Darcy law. The final nonlinear fully coupled equations reflect not only the coupling effect of the physical quantity within the porous medium, but also the coupling between the medium and the fracture. Since the extended finite element method (XFEM) has a unique advantage in dealing with fracture problems, both XFEM and the ordinary finite element method (FEM) are used to establish the numerical calculation system. During the spatial dispersion, the displacement and the pore pressure in the medium are discretized by FEM. To reflect the strong discontinuity of the fracture surface and the stress singularity at the crack tip, two kinds of additional displacement functions are introduced in the displacement model of the fracture area based on XFEM. The pore pressure enhancement function is also applied to represent the weakly discontinuous features of the normal pore pressure. Time discretization is performed using a backward difference scheme. Finally, numerical examples are provided to prove the correctness and effectiveness of the model and algorithm. Moreover, the delay of the fluid flow, the feature of the opening displacement and the pore pressure in the fracture are analyzed, and the effect of changes of the permeability and external flow on numerical results are discussed.