Use of a Higher Order Kinematic Relationship on the Analysis of CylindricalComposite Panels

摘要

An analytical study was performed to determine the critical buckling loads andnatural frequencies for composite cylindrical shells, including transverse shear effects and constant through the thickness direct strain epsilon sub z. A linearized form of Sanders shell equations are derived, including a parabolic transverse shear strain distribution. Higher order laminate constitutive relations are developed. Hamilton's Principle is applied to derive five partial differential equations of motion and the associated boundary conditions, which are then solved using the Galerkin technique. Ply layups of (0/90), (45/-45), and (0/45/-45/90) were investigated under three boundary conditions, simply supported, clamped, and a combination simple-clamped. Symmetric and nonsymmetric laminates were investigated. Curvature is shown to have a important effect on all panels investigated, due to membrane and bending coupling. Buckling loads for deeper shells are significantly higher than for flat plates. The effect on frequencies is not as great. Comparisons between various ply layups and boundaries show results are greatly dependent on the shell geometry, curvature, and boundary conditions.