Buckling Analysis of Thin-Walled Laminated Plates Considering In-Plane and Out-of-Plane Coupling Effects Under Complex In-Plane Loads

This study investigates the buckling behaviour of thin-walled rectangular laminated plates under complex in-plane loading. Linear variations in the normal transverse load components and parabolic variations in the shear load components are assumed on the plate edges. The in-plane load distributions reproduce the design solutions reported in the literature. The starting point for the considerations in this study is the classical laminated plate theory (CLPT). It focuses on cases when the laminate coupling stiffness B-submatrix components are non-zero. Six cases of in-plane loading in the pre-buckling stage are investigated. Ten examples of plates made of general laminates with different stacking sequences and the same thickness are tested. The effect of selected components of the coupling B-submatrix on the stability of the rectangular laminated plates is determined. Eigen-problem solutions for the laminated plates are obtained under complex in-plane loading, demonstrating that the proper assessment of eigen-values must include a detailed analysis of all stiffness matrix components and reduction coefficients in beam modelling. For all cases investigated in this study, the inclusion of the B-submatrix decreases the bifurcation loads.