Abstract:In order to study the hydraulic splitting law under single and double perforations, based on the Abaqus cohesive force element damage constitutive law, a finite element model containing single and double perforating fractures is established. the crack propagation process and displacement vector under different hydraulic fracturing factor D are numerically simulated. the results show that the crack propagation occurs at the crack tip in the single fracture condition. with the increasing of water pressure, the fracture with smaller D value develops along the direction of maximum principal stress. for the case with larger D value, the fracture will present a 45 degree failure characteristic. Under the condition of double crack, there is the problem of mutual interference of crack inside, D=1, D. =5 and D=20, the inner end of the two perforating fractures is first separated from each other, then overlapped with each other, and finally a interacting region is formed. when D=2, the inner end will be directly overlapped; the displacement vector of the crack reveals the crack propagation mechanism. Based on the characteristics of tensile failure and shear failure, the mechanism of tensile failure and shear failure is discussed, and the I failure is obtained.