Material:

Linear elastic, 2.00313 × 10⁷, 5.00783 × 10⁵, 1.25296 × 10⁵, 0.5 × 10⁵, 0.5 × 10⁵.

Boundary conditions:

Nodes along edge are clamped.

Loading:

0.5 at nodes B and C.

Orientations:

90° in the first layer and 0° in the second layer, with respect to the x-axis, rotated about the z-axis.

There are two elements with identical geometries in the model. The first element is defined using a composite shell section and uses a local coordinate system. The second element is defined using a general shell section, with the section stiffness matrix input directly, and is equivalent to the two-layer model presented above.

The section stiffness is: