A COMPARATIVE-STUDY OF 3 BOUNDARY-ELEMENT APPROACHES TO TRANSIENT DYNAMIC CRACK PROBLEMS

Using displacement integral representations for time dependent elastic problems, three different boundary element (BE) approaches can be considered. One is based on the time domain formulation, a second one on the frequency domain formulation, and the third on the dual reciprocity formulation. In this paper, the three BE approaches are applied and compared when used for the computation of stress intensity factors (SIF) of stationary cracks under dynamic loading. In the three cases a quadratic discretization in space and a singular quarter-point (SQP) element are used. Several problems are solved and the results obtained by the three approaches compared. The dual reciprocity approach for dynamic SIF computation is presented in this paper. Conclusions and recommendations on the capabilities of the three approaches in dynamic fracture mechanics are presented.