Nonlinear Vibration of Laminated Composite Plates in Hygrothermal Environments

Abstract

This paper addresses the phenomena of nonlinear vibration of moderately thick laminated composite plates in hygrothermal environments. The shear-deformable plate theory is modified to account for midplane stretching due to large deflections, large rotations, and dimensional and constitutive changes due to moisture-induced swelling effects and temperature-induced expansions and contractions. The in-plane hygrothermal dimensional changes are accounted for by introducing fictitious forces and moments, and the hygrothermal dimensional changes along the thickness of the plate are explicitly incorporated in the assumed form of the deformation field. The free vibration of a cantilevered laminated composite beam in hygrothermal environments is discussed as an illustrative example to demonstrate the applicability of the proposed methodology. It is anticipated that this work will be significantly relevant to applications in the defense, aerospace and manufacturing environments, where severe variations in the moisture and temperature conditions may be encountered.