Nonlinear buckling and post-buckling of eccentrically oblique stiffened sandwich functionally graded double curved shallow shells

Abstract

This paper aims to investigate the nonlinear buckling and post-buckling of eccentrically oblique stiffened sandwich functionally graded double curved shallow shells resting on elastic foundations in thermal environment. The shells are reinforced by functionally graded eccentrically oblique stiffeners with deviation angles. Two types of sandwich functionally graded double curved shallow shells with the differences of distribution of functionally graded face sheets and homogeneous core are considered. Material properties of the sandwich shells and stiffeners are assumed to vary continuously and smoothly in the thickness direction according to Sigmoid power law. The formula of force and moment resultants and the nonlinear equilibrium equations are established based on the improved Donnell theory and Lekhnitskii's smeared stiffeners technique. The analytical displacement solutions are chosen based on the trigonometric forms satisfying the boundary conditions. The value of critical buckling loads and the load – deflection curves of the shells are obtained by using the Bubnov – Galerkin method. In numerical results; effect of geometrical parameters, elastic foundations, temperature increment, compressive load and oblique stiffeners on the critical buckling loads and post-buckling load – deflection curves of the shells are studied specifically. The obtained results are also compared with others from literature to validate the accuracy of the present method and approach.