FEM Analysis on Compress Buckling Stability of Stiffened Aluminum Alloy Panels

Finite element software MSC.PATRAN/NASTRAN was applied to calculate compress buckling critical loads and analyse buckling modes of six types of stiffened aluminum alloy panels with T/Z-section stringers, and the results calculated by FEM were compared with semi-empirical calculation results. The results show that, with same cross section area, reducing stringer pitch or increasing stringer numbers could improve buckling critical loads. Buckling critical loads of T-stringer panels were higher than that of Z-stringer panels with the same stringer pitch and numbers. The first rank buckling mode of T-stringer panels presented local buckling of skin or general buckling of panel, while that of Z-stringer panels all presented local buckling of skin. The FEM simulation results were accordant with semi-empirical calculation results. Comparing with T-stringer panels, the errors between the two calculation results of Z-stringer panels were smaller.