On the Elastic Stiffnesses of Corrugated Core Sandwich

Abstract

The objective of this paper is to review and recast previous analytical approaches to the analysis of the elastic stiffnesses of corrugated core sandwich panels into the framework of first-order shear deformation laminated plate theory. Extensional, shear and bending stiffnesses will be determined and compared to measured data. It is shown that the in-plane extensional and shear stiffness and the bending and twisting stiffnesses are dominated by the face sheets and that calculated values agree with measured data. Transverse shear stiffnesses, however, are highly dependent on the integrity and shape of the core and the details of face-to-core bonding, and predictions were found to be highly unconservative. A major factor for the reduction in stiffnesses of the core is attributed to delamination damage of the web inflicted during the corrugation process.

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