Shear buckling of rectangular composite plates composed of concentric layups

The buckling load of rectangular composite plates consisting of concentric rectangular layups under shear is determined using energy minimization and an out-of-plane displacement function based on sinusoids. By construction, the present method recovers the classical solution for buckling of anisotropic plates with one layup. Also, for the case of two concentric layups where only the thickness is varied, the present method was found to be in excellent agreement with finite element results. Using the results of the present method, combinations of multiple concentric layups were found that increased the buckling load of a single layup panel by 26% without increasing the weight.