ANALYSIS OF LAY-UP OPTIMALITY CONDITIONS FOR BUCKLING OPTIMIZATION OF VAT (STEERED FIBER) COMPOSITE PLATES

The present paper is devoted to the theoretical explanation of the known numerical results of other authors on re-distributing the pre-buckling stresses to supported regions for improving the buckling behavior. The analysis of the lay-up optimality conditions (derived earlier) for buckling optimization of VAT composite plates is performed. The plates have a symmetric lay-up and loaded along their contour by the in-plane forces. The consideration employs the von Karman approach. The lay-up optimality conditions correspond to the maximization of a single-mode (lowest) buckling eigenvalue. The order of magnitude of the items of the conditions is assessed and compared.