Crack Propagation Analysis Of Expansion Joints Based On Extended Finite Element Method

Crack growth of materials is a typical discontinuous problem, it is difficult to achievesimulation of crack growth process with conventional finite element method. In order to solvethe defects of conventional methods, XFEM introduces level set function method to describecrack shape, realizing initiation and development of crack in the inner unit and avoiding thecalculating pressure on mesh refinement and re-split with conventional method. Besides,XFEM can preset crack to simulate the stress singularity of crack tip, realize damagemechanism by definition method of material weakening, so that the XFEM can not be tooepoch-making significance for studying finite element.This paper elaborates the basic theory of fracture mechanics, discusses the crackcriterion and evolution rules of materials under different conditions, simulates thedevelopment of two-dimensional cracks with ABAQUS6.12as a platform; moreover,compared answers with classical mechanics, it proves that XFEM method can still reach abetter calculation accuracy in the case of relatively coarse mesh.The calculation analysises the fracture behavior of Expansion joints when undergoinginterdental vertical load, simulates the crack development of comb plate root respectivelyunder static load and fatigue load. The result show that extended finite element method caneffectively stimulate cracking process without unit constraint and local refinement, reduce thenumber of units and cost savings, which provides a convenient way to solve practical complexproblems.