Some Observations on the Cured Shape of Thin Unsymmetric Laminates

Abstract

This paper discusses the fact that the cured shape of thin unsymmetric laminates do not conform to the predictions of classical lamination theory. Rather than being saddle shaped, as predicted by the classical theory, the paper shows that thin unsymmetric laminates cure into a shape of a right circular cylinder. This anomalous behavior has been observed by many but the paper serves to quantify the effect and to inspire investigators to begin thinking about using the phenomenon to advantage. The paper indicates that the anomalous behavior is repeatable and that thicker laminates conform to the predictions of the classical theory. Laminates of the [0/90 2 / & t h e t a s ; ] T , [0 2 /&thetas; 2 ] T and [0 4 /&thetas; 4 ] T families are investigated for this behavior and it is shown the principal curvature directions of the cylindrical shapes are predictable.

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