Automated Delamination Onset and Growth Prediction in Composite Structures

An automatic software tool for damage tolerance assessment and residual strength prediction of composite structures based on the extended finite element (XFEM) will be developed. This tool will for the first time be able to model arbitrary 2D/3D delamination crack growth without remeshing. The automated tool will be integrated with the ABAQUS implicit solver via its user-defined subroutines. GEM has secured commitments for technical support and commercialization assistance from LM Aero, Bell Helicopter, ABAQUS, and MSC. Our consultant, Professor Ted Belytschko, who pioneered XFEM, will aid in basic theory development, tool development, and provide existing XFEM solution modules that are relevant to delamination failure prediction. The XFEM methodology for a 2D delamination crack was demonstrated in Phase I. The unique features of the Phase II software product are: 1) the capability for arbitrary insertion of multiple initial delamination cracks into any finite element mesh at either element boundaries or within elements via a PATRAN GUI; 2) simulation of arbitrary crack growth without remeshing; 3) accurate extraction of strain energy release (SERR) rate along an arbitrary crack front with or without closure via a modified VCCT technique; and 4) characterization of delamination onset and growth results via PATRAN and ABAQUS’s CAE.