Pointing out that governing PDE solutions are generally difficult, the lecturer introduces the energy methods as an alternative. As an example he solves the problem of a rectangular composite plate with two concentric layups using the methods of energy minimization to determine the maximum loads and displacements. These results were then compared with FE solutions as well.

In the final part of the lecture Dr. C. Kassapoglou speaks about buckling. After using illustrations of real buckling failure cases, he moves to the example of a simply supported composite plate under bi-axial loading. The results for composite plate are then compared with an aluminum plate of the same thickness.