Work

Extended Finite Element Method for Analyzing Hydraulic Fracturing of Rock Cracks Under Compression

Year: 2025

Type: article

Abstract: In this paper, a numerical model for solving the problems of hydraulic fracturing and frictional contact of rock cracks using the extended finite element method (XFEM) is established. By considering the water pressure distribution on the crack surfaces and the virtual work principle of frictional contact on the crack surfaces, the governing equations for analyzing hydraulic fracturing and frictional contact problems using the XFEM are derived, and the implementation method of the XFEM with frictional contact and water pressure distribution on the crack surfaces is presented. Taking a flat plate with a single-edge crack as an example, the interaction integral method is used to calculate the stress intensity factor when there is water pressure distribution on the crack surface, and its results are compared and analyzed with the exact solutions. This method can give accurate calculation results. Taking a flat plate with a through crack as an example, the nonlinear complementary method is adopted to solve the frictional contact problem. This contact algorithm can effectively prevent the crack surfaces from interpenetrating, and its results are consistent with those calculated by the finite element penalty function method. Based on the XFEM, the hydraulic fracturing analysis of a flat plate with a central crack under uniaxial compression is carried out. The critical water pressure decreases as the crack length increases, and the critical water pressure increases as the external axial pressure increases. Taking a gravity dam with an initial crack as an example, the calculation results show that hydraulic fracturing will increase the Mode I stress intensity factor at the crack tip and reduce the stability of the crack at the foundation of the gravity dam.

Source: Processes

DOI: 10.3390/pr13020514

Author: Anxing Zheng

Institution: Zhejiang University of Water Resource and Electric Power

Language: English

Topic: Numerical methods in engineering

Subfield: Mechanics of Materials

Field: Engineering

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $2,896

Funders: National Natural Science Foundation of China, Natural Science Foundation of Zhejiang Province