A flexible strategy for numerical path integration

Abstract In this paper, a flexible strategy for numerical path integration is proposed using the J integral as an example to describe the algorithm that can be extended to the evaluation of other J -like integrals without difficulty. A program called PathInt is developed to run in expert mode or automatic mode. When in expert mode, the program may be controlled in a more detailed way to meet the needs of proficient researchers. When in automatic mode, the program can determine several parameters automatically according to the default settings. A numerical example of a typical elastic fracture problem demonstrates the effectiveness of the algorithm. The applicability of several finite element meshes with or without special crack-tip elements is also investigated. It is found that eight-node collapsed elements are of great potential usefulness since the results from the meshes employing them at the crack tip are satisfactory in both elastic and plastic problems.