Large deflection behavior of circular sandwich plates with metal foam-core

•A large deflection analytical model for sandwich plates is proposed.•Good agreement was reached between simulation and analytical solution.•Effects of the boundary condition, face/core thickness ratio and core strength were studied.

In this paper the ‘equal area method’ is used to investigate the load carrying capacity of circular sandwich plates (two metallic face-sheets adhered to a metallic foam-core) subjected to transverse quasi-static point central loading, and the plates are simply supported or fully clamped at the edges. During the process of the large deflection, the plate is regarded as a three dimensional body, which deforms into a shallow cone. To validate the analytical solution, a finite element simulation is performed. A parametric study is then carried out to examine the effects of the boundary conditions, core strength and face/core thickness ratio on the structural response. Results show that the analytical model gives a good description on the quasi-static behavior of circular sandwich plates as presented in finite element simulation. It is shown that the existence of an annular plastic hinge at the external boundary weakens the effects of radial stress in the case of fully clamped boundary. After the initial collapse, the face yield is the dominant failure mechanism especially at the stage of large deflection and the initial collapse of the sandwich structure is highly dependent on the face-sheets strength.