Rebecca A. Ortiz and Dr. Michael W. Hyer
National Science Foundation and Technology Center:
High Performance Polymeric Adhesive and Composites, and
Engineering Science and Mechanics Department
Virginia Polytechnic Institute and State University
Blacksburg, Virginia


When thin plates are loaded in compression, buckling becomes the most important failure mechanism. In order to use thin plates as structural members, the buckling behavior must be characterized. This research focuses on using the Finite Element Method (FEM) to calculate the critical buckling loads (P *cr) for a series of rectangular angle-ply composite plates. The effect of varied boundary conditions and engineering properties on the buckling load is investigated. It is shown that adding finite clamped and simply supported areas to the plate has negligible effect on the buckling load. However, if the plate is not damped well (zero degrees of freedom), the buckling loads increase between 0.2 and 29% depending on the lay-up. A least squares fit between experimental and manufacturer's quoted properties results in a new set of properties. The new properties, with a significantly lower E *l , , yield lower buckling loads.

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