A unified peridynamics-based framework for hydro-mechanical coupling analysis in fractured porous media

Fractures introduce significant heterogeneity into rock masses, resulting in complex hydro-mechanical coupling behaviors. By integrating the fracture seepage model with classical Biot’s consolidation theory, an extended peridynamic framework is proposed capable of modeling the response of fractured rock masses under multi-physical condition. A spring-like peridynamic interface model is developed to simulate both sealed and open fractures in rock-mass, and an adaptive dynamic relaxation method is adopted to update the deformation field, resolving the large gap in explicit time steps between the deformation and seepage fields and enhancing computational efficiency. Two benchmark examples are presented to validate the accuracy of the proposed model in simulating fracture deformation and coupled processes in fractured rock. The influences of interface type, length, and inclination angle on the consolidation behavior are systematically analyzed, and the effects of interface strength and fluid exchange coefficient on the deformation and seepage response of layered rock masses are investigated.