Analytical investigation on buckling and postbuckling of FGM toroidal shell segment surrounded by elastic foundation in thermal environment and under external pressure using TSDT

In this paper, FGM toroidal shell segments surrounded by elastic foundation and subjected to uniform external pressure are investigated by analytical method. A novelty of the study is that the Reddy’s third-order shear deformation shell theory (TSDT) with von Karman geometrical nonlinearity combined with deflection function selected with three terms is used to investigate the nonlinear stability of thicker FGM toroidal shell segments. In addition, the thermal element in the shell is also taken into account. The FGM shell is a convex and concave toroidal shell segment. It is a general form for a circular cylindrical shell. Closed-form expressions for determining the static critical external pressure load and postbuckling load–deflection curves are obtained. Effects of temperature field, foundations, material and dimensional parameters on the stability of shells are considered. This paper also shows that the use of TSDT to analyze the nonlinear stability of thicker toroidal shell segments is necessary and more suitable.