Postbuckling of Orthotropic Plates on Two-Parameter Elastic Foundation

Abstract

A postbuckling analysis of an uniformly in-plane loaded, simply supported, orthotropic rectangular plate resting on a two-parameter (Pasternak-type) elastic foundation is presented in this paper. The formulations are based on the large-deflection theory, and the nonlinear, generalized Karman-type equations of orthotropic plates are solved. The analysis uses a deflection-type perturbation technique to determine buckling loads and postbuckling equilibrium paths. The initial geometrical imperfection of the plate is taken into account. Numerical examples relating to the performances of isotropic and orthotropic, perfect and imperfect rectangular plates resting on two-parameter elastic foundations from which results for Winkler elastic foundations are obtained as a special case, are presented. An elastic foundation's effect on the postbuckling behavior of plates is also evalutated for various values of foundation stiffness parameter. Typical results are presented in nondimensional graphical form. To the best of the writer's knowledge, the main results appear in the literature for the first time.