On the applicability of simple shapes of delaminations in buckling analyses

The possibility to accurately analyse the buckling and postbuckling behaviour of plates with delaminations of irregular shapes by utilisation of circular or elliptic delaminations was studied. The behaviour of compressed plates with delaminations of irregular and corresponding smallest enclosing circular and elliptic shapes was predicted by computational analyses and compared in terms of buckling loads and maximum values of the energy release rates found along the delamination boundaries. The study indicates that utilisation of circular delaminations could provide highly inaccurate results. Moreover, for truly accurate analyses of the buckling and postbuckling behaviour of delaminated structures it seems to be inevitable to use as precise representation of the shape of delaminations as possible.