Analytical determination of the critical load of delaminated plates

The presence of a delamination in a composite material may cause early buckling which could lead to structural collapse. Earlier studies have shown the effect of the delamination length both experimentally and numerically on the critical load of a laminated plate. In this paper an analytical study is performed involving the length of the delamination and its location, resulting in a characteristic equation for the buckling. The closed-form analytical solution for the critical load agrees well with published numerical results which use both a Rayleigh-Ritz and a finite-element approach.