Cured Shape of Unsymmetric Laminates with Arbitrary Lay-Up Angles

Abstract

The warping analysis of the general unsymmetric laminates with arbitrary lay-up angles is still not fully understood whereas the cross-ply laminates have been characterized well. This paper presents the formulation that treats the curvatures and prin cipal direction of curvature of the cured shape in unsymmetrically laminated composites. The effect of spatial dependence of in-place strains on curvatures is significant near the bifurcation point in the case of laminates having the stacking arrangement in which snap- through phenomenon occurs. It is shown that the principal direction of curvature calculated from classical lamination theory agrees with this theory in the limited range of length-to-thickness ratios of laminate. Curvatures and principal direction of curvature ac cording to the length-to-thickness ratios, number of layers, and lay-up angles of the lami nate are presented.

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