Asymptotic Analysis for the Curved/Straight Sandwich Panel Junctions

Abstract

Cylindrical bending of a sandwich panel assembly consisting of straight and curved sections is considered. The sandwich assembly is statically determinate, loaded by a uniform pressure and possibly by forces and moments at its edges. The influence of the change of geometry upon the stresses and displacements at the transition zone between the different panel sections is investigated. An exact asymptotic mathematical model based on a number of small parameters is derived. The model assumes the faces of the sandwich panels to be thin elastic beams obeying the Kirchhoff-Love assumptions, while the isotropic core is treated as a 2-D elastic medium. An asymptotic expansion technique is exploited to derive analytical estimate formulae for calculating the deformation and stress distribution characteristics at the critical sections of the assembly. A numerical example illustrates the applicability of the derived formulae, and the validity of the proposed approach is demonstrated through comparison with FEM calculations.

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