Numerical Simulation Research on the Interactive Propagation of Hydraulic Fractures and Natural Fractures

In order to study the fracture propagation behavior after the interaction between hydraulic fractures and natural fractures, the cohensive unit of Abaqus finite element software is used to simulate the influence of natural fractures in the rock on the propagation behavior of hydraulic fractures. The simulation results show that when the approach angle is kept constant, as the in-situ stress difference increases, hydraulic fractures are more likely to penetrate the natural fractures and expand along the direction of the maximum horizontal principal stress; while the stress difference remains the same, as the approach angle increases, hydraulic fractures are easier to penetrate natural fractures and expand along the direction of maximum horizontal principal stress. When the approach angle is kept constant, as the tensile strength of natural fractures increases, hydraulic fractures are more likely to penetrate the natural cracks and expand along the direction of the maximum horizontal principal stress; while the tensile strength of natural cracks remains unchanged, as the approach angle increases, the probability of forming a complex fracture network between hydraulic fractures and natural fractures is reduced, and it is easier to penetrate the natural fractures and expand along the direction of the maximum horizontal principal stress.