Failure Analysis of Composite Plates Subjected to Localized Loadings via a Unified Formulation

Abstract

A failure analysis of composite plates accounting for localized loadings is presented in this work. A unified formulation is adopted to derive classical, higher order, layerwise, and mixed theories. A closed form, Navier-type solution is assumed. Simply supported, cross-ply laminates are investigated. Plates are subjected to a stepwise loading, an off-centric localized one and a localized moment. First-ply failure loading and index are obtained via several failure criteria. The influence of the side-to-thickness ratio is accounted for investigating thin and very thick plates. Symmetric and asymmetric stacking sequences are investigated. The accuracy of the proposed theories is assessed. On the basis of the obtained results, it can be concluded that higher order models are required for a correct failure analysis in which the three-dimensional stress state attributable to the localized loadings is accurately described.