A five-variable refined plate theory for thermal buckling analysis of composite plates

This research is devoted to investigate the thermal buckling analysis behaviour of laminated composite plates, by applying an analytical model based on a refined plate theory (RPT) with five independent unknown variables. The theory accounts for parabolic distribution of the transvers shear strains through the plate thickness, and satisfied the zero traction boundary condition on the surface without using shear correction factors, hence a shear correction factor is not required. The governing differential equations and associated boundary conditions are derived by employing the principle of virtual work and solved via Navier-type analytical procedure to obtain critical buckling temperature for simply supported boundary condition of symmetric and antisymmetric cross-ply and angle-ply laminated plates. MATLAB 2018 program is used to investigate the effect of thickness ratio (a/h), aspect ratio (a/b), orthogonality ratio (E1/E2), coefficient of thermal expansion ratio (a2/a1) and numbers of layers on thermal buckling of laminated plate. It can be concluded that this theory gives good results when compared with other theory.