Stress distributions and stiffness anisotropy of circumferentially corrugated shells under uniform external pressure

As an excellent pressure structure, circumferentially corrugated shells have been widely used in many fields, such as ocean engineering and aerospace. At present, the circumferentially corrugated shells have only obtained good buckling performance in tests and finite element analysis. However, the corrugated shells have not been further analyzed in theory, and some new problems have been found in tests. The geometrical parameters of shell structures determine the stress distributions and stiffness anisotropy, and the von Mises stress and local stiffness determine the collapse form and collapse location. The relationship between them has not been explained. The study of this problem will be beneficial to establish the active design theory of the circumferentially corrugated shells. Therefore, this paper aims to investigate the von Mises stress and stiffness anisotropy of the circumferentially corrugated shells. Some corrugated shells with uniform thickness and some corrugated shells with non-uniform thickness are established. The parameters used to represent the corrugated structure and the degree of stiffness anisotropy are proposed. The influence of corrugation parameters on the stress distributions and stiffness anisotropy is studied by finite element method and theoretical analysis, the mechanical behaviors of two types of shells under uniform lateral external pressure is perfectly explained. It provides a direction for the design and optimization of these shells. In addition, a new circumferentially corrugated shell is proposed at the end of this paper. It has good mechanical properties, which will make it possible to further reduce its weight.