Crack-morphological aspects in fracture mechanics

Fracture mechanics can be regarded as a methodology to characterize the actual crack by using the parameters given by the analysis of a simple mathematical crack model. Therefore, the selection of these crack models has very significant meanings. In recent years, several precise crack models have been proposed.In this paper, we paid attention to the influences of the two-dimensional crack geometry and presented the numerical value of the elastic analytical solutions for the non-linear shaped cracks, those are, the bent, the curved and the branched crack. On the basis of these results, the characteristics of these cracks were discussed and the methods of approximate replacement to a simple straight crack were proposed.We examined a zig-zag growth of crack and the crack branching observed in actual fracture processes.