Stresses Around a Biaxially Loaded Fastener Hole in a Laminate of Finite Geometry

Abstract

The stress analysis of a biaxially loaded fastener hole in a laminate of finite width has been conducted using a complex variational approach developed at the Institute for Aerospace Research. The formulation of the complex variational approach developed is described in this paper. In this approach, an infinitely stiff fastener is assumed to be in contact with one half of the hole edge. The fastener load is in equilibrium with the applied loads along the exterior edges, and a cosine distribution over the contact region is assumed. The stresses around a single fastener hole under biaxial loading conditions were determined. Various anisotropic laminates were analyzed. The effects of the biaxial loading ratios on the joint performance were examined. Results from the analytical approach are presented and discussed in this paper.

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