Different buckling modes in axially stiffened conical shells

Different modes of instability might occur in thin-walled stiffened shells. In particular, local shell and stringer buckling modes and global buckling mode might develop in axially stiffened cones. In this paper, such modes a re studied in conical shells under axial compression through a linear eigen value finite element analysis. In order to examine buckling modes in isolat ion (in line with typical simplified formulae) as well as competing modes t ogether, use is made of different finite element models, including discrete and smeared models. Changes of buckling modes are captured by varying stif fener slenderness, number of stiffeners and tapering angle, treated as desi gn parameters. Some evidence of mode interaction is recorded by the cluster ing of eigenvalues/eigenmodes. (C) 2001 Elsevier Science Ltd. All rights re served.