Strength of biaxially loaded orthotropic plates

An approximate and simple method for rectangular orthotropic plates, loaded biaxially along two mutually perpendicular directions is presented. The theory is based on the energy method and it is free from difficult calculations such as those encountered when large deflection theory is used. Effects of initial imperfections are taken into account. The number and lengths of half-waves are assumed to be the same in the post-buckling stage as at incipient buckling. The finite buckled shape in the post-buckling stage is taken to be the same as that during incipient buckling. The Von Mises yield criterion is employed to determine the upper bound solution of the plate. Interaction curves for square plates subjected to longitudinal and transverse stresses, applicable to three different boundary conditions, four edges simply supported or four edges clamped or two opposite edges clamped with the other two edges simply supported, are presented in a non-dimensional form. Results for plates having different values of plate slenderness (b/t) and flexural rigidity ratios, D2/D1 are given.