Comparison of a Higher Order Theory for Sandwich Beams with Finite Element and Elasticity Analyses

Abstract

Sandwich construction is known to provide high stiffness with light weight. However the question of analysis methods for the deformation and stresses in sandwich construction is still not completely settled. A higher order theory for sandwich beams has recently been presented in the literature. This theory is compared with a two-dimensional finite element analysis and elasticity solution in the present work. The results show that both the higher order theory and the finite element analysis predict strain concentrations in the faces adjacent to support and concentrated load regions, and overall good agreement is obtained between these methods. Classical and first order shear deformation theories are not capable of predicting these strain concentrations. Stress and strain distributions in the core are not in as good agreement in these regions, due to the simplifying assumptions made by the higher order theory. The results show that the higher order theory is an effective tool in predicting the stresses in the faces and the interface between the face and core, although the shear stress distributions in the core are not as well predicted.

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