An enriched Dual Boundary Element Method for Fracture Mechanic

The direct collocation Boundary Element Method (BEM) has been enriched in the Partition of Unity sense by a set of functions known to describe the displacement field in the immediate vicinity of a crack tip. The Dual BEM approach is adopted to preclude the need for substructuring. The enrichment introduces a small number of additional degrees of freedom, and this therefore requires a corresponding number of auxiliary integral equations. The paper describes the enrichment strategies that may be employed and the results demonstrate that the enrichment provides for approximately one order of magnitude improvement in accuracy in comparison with the conventional, unenriched Dual BEM.