Introduction

In this first lecture Dr. C. Kassapoglou tells briefly about the history of advanced composites in the context of civil aviation and recaps the basics of Classical Laminated Plate theory.

He explains the difference in behavior between metals and the composite materials under loading, specifically elastic response and failure. He gives the overview of the composite failure mechanisms, showing the students how complex the problem of a failure determination may be.

The understanding of orthotropic composite materials is given and the constitutive relations for a single ply are shown. Dr. C. Kassapoglou continues his lecture with the assumptions relating to thin laminates, which allow to simplify the stress-strain equations.  Next he shows how to go from single ply stiffness to the laminate stiffness and how to define the stress resultants.  Finally, the behavior of laminates with applied in-plane loads are described.