Postbuckling response and failure of symmetric laminates under uniform temperature rise

A nonlinear finite element method, which is based on the von Karman–Mindlin plate theory and the principle of minimum total potential energy, is used to study the response and the first-ply failure of thin laminated composite plates under uniform temperature rise. The temperature dependent mechanical and strength properties, their effect on response and failure of laminates and the onset of delamination in the process of first-ply failure computation are some of the features incorporated in the nonlinear formulation. The load–displacement curves for different types of graphite/epoxy laminates are obtained. Stresses are computed to determine the first-ply failure temperature based on the Tsai–Wu failure criterion. The effect of the fiber orientation, the number of lay-ups and the plate aspect ratio on the response as well as the first-ply failure is studied.