Influence of side boundary condition on compression performance of aluminum alloys stiffened panels

Engineering aircraft stiffened structure reinforced by a beam or wall panels restriction are simply supported, and high strength aluminum alloys stiffened panels constrained by side boundary will exhibit different compression performance from panels with unsupported side boundary in axial compression. Test and numerical calculation research were conducted to study this phenomenon. Moiré interferometry and strain gauges were used to monitor the buckling and post-buckling process. Based on the software of ABAQUS, a finite element model was developed. Johnson-Cook constitutive model with ductile damage and shear damage was used to study compression performance of panels with different side boundary conditions. The calculated results are coordinated with the tested results very well. The results indicate that all skins of side simply supported panels buckle simultaneously, while only side skins of unsupported panels buckle. Despite the buckling load for unsupported panels is well lower than that for side simply supported panels, the former's ultimate load only almost decreases by 9%.