Fabrication and testing of composite isogrid stiffened cylinder

This paper describes the fabrication and testing of the composite isogrid stiffened cylinder. The purpose of the axial compression test was to identify various failure modes that are present in the structures such as rib crippling, skin (pocket) buckling, and general instability. The rib buckling was found to be the critical failure mode for the isogrid cylinder. The isogrid cylinder has been demonstrated to be tolerant to structural damage due to the multiplicity of load paths. The cylinder continued to resist compression loading even after one or more ribs had fractured. The imperfections to the cylinder resulted in reduced buckling resistance but this problem can be overcome by advancement in the manufacturing methods. © 1999 Elsevier Science Ltd. All rights reserved.