Abstract

The width and loading conditions effects on free-edge stress fields in composite laminates are investigated by using a three-dimensional finite element analysis. The analysis includes a special free-edge region refinement or superelement with progressive substructuring (mesh refinement) and finite thickness interply layers. The different loading conditions include in-plane and out-of-plane bending, combined axial tension and in-plane shear, twisting, uniform temperature, and uniform moisture. Results obtained indicate that axial tension causes the smallest magnitude of interlaminar free edge stress compared to other loading conditions; laminates with practical dimensions may not delaminate because of free edge stresses alone since the magnitude of these stresses are found to be quite insignificant.

Issue Section:
Research Papers
Keywords:
3-D finite elements, superelements, progressive substructuring, fiber composites, interply layers, 3-D stress fields, axial tension, in-plane shear, out-of-plane shear, out-of-plane bending, twisting, combined tension/shear, uniform temperature, uniform moisture

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