XFEM Toolkit for Crack Path and Life Prediction of Aluminum Structures

This study is focused on the development and demonstration of the capability of the XFEM toolkit for ABAQUS (XFA) to predict fatigue crack growth and remaining life of 2D and 3D aluminum structures. The new technique couples the level set based crack description with the fast marching method (FMM) for crack growth. Both the jump and tip enrichment functions are used to accurately capture the crack tip driving force during the fatigue crack growth prediction. To facilitate the crack insertion and definition within an existing FEM model without a crack, a customized ABAQUS CAE is developed to allow the user to specify the location, orientation, and size of the crack that is independent of the existing finite element mesh. Verification and validation studies are performed for the curvilinear crack growth and life prediction of 2D modified compact specimens and a 3D Tweldment. The developed XFA package will allow the user to produce quantifiable metrics relating fatigue and fracture calculations to structural performance. In addition, the tool can be used to interpret the structural healthy monitoring data for risk informed decision making on repair, maintenance, and life extension options.