Simplified evaluation of fundamental natural frequencies or compressive buckling loads for symmetrically laminated plates with bending twisting coupling

In this paper we propose a simplified evaluation method of the fundamental natural frequencies or the compressive buckling loads for simply supported symmetrically laminated plates with bending-twisting coupling. A highly accurate approximate solution for the fundamental frequencies or the buckling loads is obtained using the second-order perturbation method. The fundamental frequencies or the buckling loads for any kind of symmetric laminates can be evaluated from the contours on the lamination parameter planes obtained using the perturbation method. The present evaluation method may be an effective design tool for evaluating vibration and buckling of general symmetric laminates.