Abstract: Taking a cellular shell of regular hexagonal honeyc- omb sandwich as example, the buckling theories of Euler colu- mn and thin-walled plate are combined. The treble series solut- ion of cellular shell buckling mode and the critical loading formulas are derived. The short cellular shell, medium length cellular shell, and the long cellular shell have been classified according to the failure forms of cellar structure. The perfectly designiug theory is builtup and the critical loading chart is pro-vided. It can be found that the different classical cellular shell has different controlling equation and first-order buckling form-ation. Finally the calculated results with derived formulas are coincidence with 3D finite element analysis results. The concl-usions will have significant reference for the study of a honeyc-omb sandwich structure and thin-walled prismatic shell.

Key words: Buckling mode, Critical loading, Honeycomb sandwich structure, Numeric simulation