说明：  层合板的刚度的计算和验算，包括拉伸刚度A、弯曲刚度D以及耦合刚度B。 首先要给定层合板的各个参数，具体有：层合板的层数N；各单层的弹性常数E1、E2、 、G12；各单层对应的厚度；各单层对应的主方向夹角 。
(The stiffness of laminated plates is calculated and checked, including tensile stiffness, A, flexural stiffness, D and coupling stiffness B. First of all, it is necessary to give the parameters of laminated plates, such as the number of plies N, the elastic constants of each layer, E1, E2, and G12, the thickness of each monolayer, and the angle of the main direction corresponding to each single layer.)