Some simple solutions for buckling loads of thin and moderately thick cylindrical shells and panels made of laminated composite material

Abstract

The objective of the present paper is to present a simple analytical solution for computing bifurcation buckling loads of thin and moderately thick orthotropic cylindrical shells and panels subjected to axial compression and normal pressure. That solution • — does not necessarily make use of the simplifying assumptions of shallow shell theory, and • — takes the flexibility with respect to transverse shear loads into account, which is supposed to be relatively high with laminated composite structures. The analysis is based on the governing nonlinear equations and boundary conditions of deep and shallow shell theory. They are linearised to yield the differential equations for bifurcation buckling. The linearised set admits a single-term analytical solution when the cylinder ends or panel edges are simply supported. It reduces the task to a small size (3∗3) algebraic eigenvalue problem that can be solved by standard methods. A computer program BOSCAP (Buckling of Orthotropic Shear-flexible Cylinders And Panels) is developed based on the above mentioned formulation which is very quick and easy to use during design trials or in automated optimization. A series of numerical examples is presented to demonstrate effects of transverse shear flexibility and curvature. Good agreement with some test results is shown.