Boundary element formulations for the dynamic analysis of cracked structures

Boundary element methods, which allow the analysis of dynamic crack problems with a single-region formulation are presented. All the methods generate a distinct set of boundary integral equations by specifying the displacement equation on one crack surface and the traction equation on the other. This technique is combined with a time domain formulation, a Laplace transform formulation or the dual reciprocity method. Dynamic stress intensity factors are calculated using the quarter-point elements and a path independent (J) over cap-integral. These methods are used to study dynamic behaviour of stationary cracks in finite domains and in two-dimensions. The three approaches are applied to a mixed-mode crack problem. Formulation details of the methods and computational efficiency as characterized by memory, time requirements and accuracy are subsequently discussed and compared.