| Hooke's Law of a Composite Lamina |
 |
|
The constitutive equations describe how the stresses and straines relate within each lamina (Hooke's law). Detailed discussion can be found in the following sections: stress-strain relations of materials, stress-strain relations of lamina for principal directions, coordinate transformation of lamina for arbitrary orientation, and stress-strain relations of lamina for arbitrary orientation. For a single lamina of any orientation,  where  and [C] is the principal stiffness matrix. Conversely,  where  and [S] is the principal compliance matrix. The coordinate transformation matrix is  and the angle  |
is illustrated below
| Hooke's Law of a Lamina within Laminated Composites |
|
|
For a single lamina of any orientation within a laminated composite plate, the same relations apply. Let the subscript k indicate the kth layer of the laminate, counting from the top, we can write  and,  |
