考虑渗流应力耦合的XFEM水压致裂模拟.

An extended finite element incremental iterative solution scheme for the hydraulic fracturing problem with saturated porous media was derived. Based on the analysis of analytical solutions of crack tip displacement field of infinite plate with central crack, a new cohesive crack tip strengthening function was constructed according to the deformation characteristics of modelⅠand modelⅡ, which reduced the degree of freedom of the nodes affected by the crack tip strengthening from 8 to 2 in the traditional extended finite element method (for plane problem). The issue has greatly reduced the computation scale. Taking a porous medium plate with a central oblique crack as an example, the correctness of the cohesive crack tip strengthening model was verified. The condition numbers of Jacobian matrices of two kinds of crack tip strengthening modes were calculated. The results show that the accuracy of the extended finite element method under the cohesive crack tip strengthening mode is the same as that of the traditional extended finite element method. When the grid is denser, the accuracy of this method is higher than that of the traditional one. Finally, the improved cohesive crack tip strengthening model is applied to the hydraulic fracturing simulation of concrete gravity dam and good results are obtained. [ABSTRACT FROM AUTHOR]