Postbuckling of Reissner—Mindlin plates under biaxial compression and lateral pressure and resting on elastic foundations Original Research Article

Using the first-order shear deformation plate theory and including plate-foundation interaction, a postbuckling analysis is presented for a simply supported, rectangular Reissner—Mindlin plate subjected to biaxial compression combined with lateral pressure and resting on a two-parameter (Pasternak-type) elastic foundation. The lateral pressure is first converted into an initial deflection and the initial geometrical imperfection of the plate is also taken into account. A perturbation technique is presented for the determination of buckling loads and postbuckling equilibrium paths. A computer program has been developed and a number of examples are solved to illustrate their application to the performance of perfect and imperfect, initial lateral pressurized moderately thick plates subjected to biaxial compression and resting on two-parameter elastic foundations from which results for Winkler elastic foundations are obtained as a limiting case. The influence played by a number of effects, among them foundation stiffness, the plate aspect ratio, the biaxial load ratio, transverse shear deformation and initial lateral pressure are studied.