Dual boundary element assessment of three-dimensional fatigue crack growth

Abstract

In this paper a general procedure for the analysis of three-dimensional multiple fatigue crack growth is presented. The crack propagation is simulated using an incremental crack extension analysis based on the strain energy density criterion and the Paris law. For each crack extension the dual boundary element method is used to perform single region analysis of the cracked component. Stress intensity factors are computed along the crack fronts using a displacement-based method. Crack extensions are automatically modelled with the introduction of new boundary elements along the crack fronts and a localized rediscretization in the area where the cracks intersect the free surfaces. The capability of the procedure is demonstrated by solving a number of multiple edge-crack examples. Results are compared with experimental observations.