Numerical study on crack-tip stress intensity factor for inclined crack emanating from the edge of a hole in finite-thickness plates

摘要

Applications of fracture mechanics have traditionally emphasized on transverse crack growthproblems under single-mode loading.There are many empiric models used for fatigue crack growthprediction.These models need the crack-tip stress intensity factor history along the crack path,which is typically only available for simple component geometry and loading.Unfortunately,singlemodeloading infrequently occurs in practice and usually the cracks are subjected to mixed-modeloading and,as a consequence the crack deviates from its original direction.Thus,the cracktipstress intensity factors should be estimated accurately to predict the crack propagation pathcorrectly.In this paper,a finite element analysis has been carried out to estimate crack-tip stressintensity factors for the plate with inclined and through-the-thickness crack emanating from theedge of a hole.The plate has been modelled by using quadratic quadrilateral plane elementsand quarter-point singular elements are employed around the crack tip.A plate with inclinedcrack of varied geometrical parameters,emanating from the edge of a square or circular hole,boundary conditions,mixed-mode loadings and materials has been investigated.The result of thisinvestigation provides a convenient data for determining the direction of crack path that a plateunder mixed-mode loadings.