Two approaches to predict the initiation of delamination at the edge of a hole in a [0/90]S graphite/epoxy laminate under in-plane compression loading are presented. The first approach, which is used to analyse interlaminar stresses in a laminate without delamination, employs singular finite elements at the edge of the hole, the strength of the singularity being varied around the edge. The second analysis is a fracture mechanics analysis based on the strain energy release rate. Both analyses predict that the risk of delamination is highest about 60° away from the loading direction.
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