Buckling analysis of shear‐deformable orthotropic laminated plates with rotational restraints

Buckling of shear‐deformable laminated plates is investigated in the present study. A closed‐form method to determine the buckling load is developed within the framework of Reddy's Third Order Shear Deformation Theory (TSDT). The considered orthotropic plates are under uniaxial compression and simply supported at all edges with rotational restraints at the unloaded edges. This allows the modelling of a number of structural situations, e.g. local buckling of beams or the skin fields of stiffened composite panels, for which only the rotational stiffness of the surrounding structure is required. The analysis approach is based on the Ritz method and employs simple shape functions with few variables for the deflection and rotations, which finally leads to an explicit approximate solution for the critical buckling load. The comparison to the Lévy‐type solution shows a satisfactory agreement. The new approach is very simple and highly computationally efficient, which provides a great advantage for example in optimisations.