The purpose of this study is to investigate the disturbance law between rock fractures during the coupling process of high-voltage electric pulse-hydraulic fracturing. Based on elasticity, fracture mechanics, damage mechanics, the discharge process of high-voltage pulse discharge under water pressure (3 MPa) was numerically simulated by using extended finite element method, and the cracks in rock mass were analyzed. The results show that under a discharge voltage of 5 kV, the maximum crack width of high-voltage electric pulse-hydraulic fracturing is increased by 35% compared to traditional hydraulic fracturing. With the increase of discharge voltage, the maximum crack width and crack initiation pressure of cracks increase, which improves the interference ability between cracks. In addition, the interference between cracks in rock mass is also related to the principal stress difference, injection rate and the number of cracks. Specifically, under the same voltage, the faster the injection rate, the longer the crack length, the more obvious the stress shadow effect, and the stronger the disturbance between cracks; Under the same injection rate, the larger the principal stress difference, the more obvious the directionality of the crack extending towards the maximum principal stress. The initiation pressure and maximum crack width both decrease with the increase of the principal stress difference. Multiple crack branches can expand and cross each other at the same time, and the stress shadow area of three cracks is wider than that of two cracks. The research results aim to provide a theoretical basis and research method for the research of underwater high-voltage electric pulse fracturing and coal seam permeability enhancement technology, and lay a certain foundation for artificial control of cracks in practical projects.
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