Buckling behavior of grid stiffened composite conical shells subjected to the lateral pressure

Abstract

This paper presents the buckling behavior of the grid stiffened composite conical shell subjected to the lateral pressure. A smeared method is employed to equivalent grid structure into a layer. For this purpose, a typical unit cell is chosen for analyzing forces and moments on it. Therefore equivalent stiffness parameters due to the grid structure are determined. By determining the stiffness parameters of the shell and superimposing with those of the stiffeners, equivalent stiffness of the whole structure is obtained. Governing equations are established based on the Donnell shell theory. The power series method is used to extract the buckling load of the stiffened shell. To validate obtained results, a 3 D finite element model is built using ABAQUS software. The comparison showed that the analytical solution is qualified enough to study the buckling behavior of the grid stiffened composite conical shell. Through this study, the effect of a set of important parameters due to stiffeners like stiffener orientation angle, the number of stiffeners, and due to due to shell like lamination angle and semi-vertex angle are investigated, and finally are presented based on this study results.