The effect of buckling and post-buckling behavior of laminated composite plates with rotationally restrained and Pasternak foundation on stacking sequence optimization

This paper presents a stacking sequence optimization for maximizing the buckling load of rotationally restrained laminated composite rectangular plates with different boundary conditions resting on an elastic Pasternak foundation subjected to uniaxial and biaxial in-plane static loads. The Mindlin Plate Theory (MPT), which considers the first-order shear deformation effect, is used to extract the characteristic equations of the plates under in-plane loading, including plate-foundation interaction. The buckling problem of the laminated plates is analyzed by the Rayleigh–Ritz method. The aim of optimization is to maximize the buckling load and post-buckling load capacity by using the Genetic Algorithm (GA) method, and the design variable is the ply orientation. The results showed that the optimal orientation, θ, of the laminated square plate under biaxial in-plane loading with various conditions is 〖45〗^∘ approximately. The existence of a foundation, clamped boundary conditions, and high aspect ratio lead to increase the optimal orientation.