Post-Buckling Design Analysis for Stiffened Helicopter Fuselage Aluminum Panels

Within the scope of the study presented in this paper, load carrying capacity and buckling behavior of a stiffened aluminum panel designed by adopting current design application and 'Post –Buckling Design' approach were investigated experimentally and numerically. The test specimen that is stabilized by Z-type stiffeners and manufactured from aluminum 2024 T3 Clad material was tested under compression load. Buckling behavior was observed by means of 3 - dimensional digital image correlation (DIC) and strain gauge pairs. The experimental study was followed by developing an efficient and reliable finite element model whose ability to predict behavior of the stiffened panel used for compression test. While finite element model was being constructed, non-linear behavior associated with material and geometry was considered. Experimental and numerical results in terms of load - shortening curve, strain-load curves and buckling mode shapes were compared for verification. It is concluded that 'Post-Buckling Design' approach proved its structural capability by giving a safe operating area after initial buckling to collapse.