Dimensional Analysis of Buckling of Stiffened Composite Shells

Abstract

Dimensional analysis is applied to a simple model of stiffened laminated cylindrical shells to determine the dimensionless parameters that characterize the buckling of these structures. Donnell shell theory is used to describe the kinematic deformation of the shells. The axial and ring stiffeners are modeled using the smeared technique. A nondimensional load is defined as a function of nine nondimensional parameters, which are a combination of the material and geometric properties of the shell. Additional assumptions regarding the construction of the shell walls can be used to reduce the number of nondimensional parameters. Some simply supported shells subjected to hydrostatic pressure are examined to demonstrate the use of the dimensionless parameters. Estimates of the imperfection sensitivity of these shells are made using Koiter's asymptotic theory. The dimensional analysis provides a framework for the systematic investigation of the relationship between material, geometry and the buckling loads of stiffened composite shells. The results of this analysis are intended to provide information that can be used in the preliminary stages of a shell design.