Buckling of imperfect stiffened cylindrical shells under axial compression

Abstract : Axial buckling tests on machined integrally stiffened cylindrical shells were carried out. Complete mappings of the shell imperfections and the prebuckling growth were obtained. The lightly ring-stiffened shells behaved in a manner similar to the isotropic shells that were previously tested. For these shells, the predominant prebuckling deformation consisted of a half-wave in the axial direction with several circumferential waves. The similarity of the lightly ring-stiffened shells and the isotropic ones suggests that the uniqueness of the buckling mode for stiffened shells may not greatly influence the prebuckling behavior. The heavily ring-stiffened shells showed a sizable amount of short wave length axisymmetric growth before buckling. Buckling in all cases resulted in an asymmetric pattern. The stringer-stiffened shells showed a prebuckling behavior also similar to the isotropic results. However, the buckling pattern consisted of longer axial wave lengths. Correlation of the experimentally obtained buckling loads with linear buckling theory showed good agreement in most cases. (Author)