Investigation on the square cell honeycomb structures under axial loading

To investigate into the collapse of a sandwich panel or beam with a square cell honeycomb, the novel plate model and beam model are developed according to the cross-sectional symmetry of the cell. The treble series solution of buckling mode is presented, and the formulas of critical compressive stress on skins are derived. The honeycomb sandwich panels are classified as thin, medium and thick plates based on their failure forms. It is found that the different kinds of cells have different buckling modes and different parameter governing equations. A new iterative optimization design method for a square honeycomb sandwich panel is developed and the curves of critical compressive stresses with geometrical parameters are provided in details. Finally, the 3D finite element numeric simulations have validated the formulas presented by this paper. Our study reveals some mechanical characteristics of the square honeycomb sandwich structures.