Influence of Fiber Orientation and Ply Thickness on Hygroscopic Boundary-Layer Stresses in Angle-Ply Composite Laminates

Abstract

The influence of fiber orientation and ply thickness on hygroscopic boundary-layer stresses in angle-ply composite laminates is studied. Based on the recently developed hygroelasticity theory for anisotropic composites, complete solutions are obtained for the hygroscopic stresses in [θ/-θ/-θ/θ] graphite-epoxy laminates with various fiber orientations and ply thicknesses. Both variables are shown to have significant effects on the develop ment of in-plane and interlaminar hygroscopic stresses. Important parameters characterizing the boundary-layer behavior such as hygroscopic edge stress singularities and stress intensity factors are presented. Hygroscopic boundary-layer widths are determined also for various cases by considering strain energy density distributions along the ply interface.

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References

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