A higher-order plate element for accurate prediction of interlaminar stresses in laminated composite plates

Lower-order finite elements have been conventionally used to solve a wide range of practical problems involving laminated composite plates. However, these elements are unable to provide accurate distributions of stress resultants in structures with free edges and stress singularities. Thus, the objective of this paper is to present a higher-order triangular plate element that is based on the third-order shear deformation theory and a layer-wise plate theory of Reddy for the bending analysis of laminated composite plates. It will be shown herein that the proposed element is able to accurately predict the shear forces and twisting moments as well as the transverse shear stresses across the thickness of a laminated composite plate. Unlike the usual deflection criterion used for establishing the convergence performance of most finite elements, the present study employs a stress analysis which is pivotal in the design phase of a structural component. Finally, the developed element is shown to be able to handle complex problems involving stress singularities more efficiently as compared to some widely used lower-order finite elements.