@RM I modelled a cross-ply Laminate as shown below (L is considered to be 100 units).
To find the in-plane stiffness matrix (A) and out-of-plane shear stiffness matrix (H), I computed in-plane properties Ex, Ey, vxy, and Gxy, and out-of-plane shear constants Gxz and Gyz using boundary conditions in the following table. Then I derived the elements of A and H matrix using the following relations.
(Question?) To find the elements of D matrix I am not sure what boundary condition should I use to find Efx, Efy, vfxy, and Gfxy in order to compute elements of D matrix using following equations.