Three dimensional biaxial buckling analysis of functionally graded annular sector plate fully or partially supported on Winkler elastic foundation

In this paper, buckling analysis of functionally graded annular sector plates subjected to uniform in-plane compressive loads based on three dimensional theory of elasticity is investigated. Moreover, influence of full or partial Winkler-type elastic foundations is considered. In-plane normal compressive loads have been applied to either radial, circumferential, or all edges of annular sector plates. The material properties vary continuously through the thickness of plate according to a power law distribution while Poisson's ratio is assumed to be constant. The governing equations are developed based on the principle of minimum total potential energy and solved based on finite element orthogonal integral equations. Buckling loads are obtained based on a generalized geometric stiffness concept. In this regard, effects of both pre- and post-buckling modes are considered. The effects of material gradient exponent, different sector angles, aspect ratio, thickness ratio, loading condition, different shapes of partial elastic foundation and foundation stiffness on the buckling loads and mode shapes of movable simply supported FGM annular sector plates have been investigated to draw practical conclusions.