The concept of varying the lamination sequence around the circumference of a noncircular composite cylindrical shell to enhance axial buckling capacity is investigated. The concept, which is a form of material tailoring, is considered as a viable approach for possibly off-setting the disadvantages of having the cylinder radius of curvature vary with circumferential position. A cylinder with an elliptical cross section is considered, and the lamination sequence is varied in a stepwise fashion with circumferential position, as opposed to the ideal case of varying the lamination sequence continuously, like the cylinder radius of curve does. A quadrant of the cylinder is divided into three regions: a crown region, the flatter portion of the cross section; the side region, the more highly curved portion; and the region in between, or middle region. Each region is assumed to be constructed of either a quasi-isotropic or axially-stiff laminate, so eight combinations of laminates are investigated. Of interest are the prebuckling deformations, the buckling load, the load drop which accompanies postbuckling collapse, and the collapsed load, all as a function of the various laminate combinations. An all quasi-isotropic cylinder is taken to be the baseline. It is shown that a cylinder with axially-stiff side regions and quasi-isotropic crown and middle regions results in the highest buckling load of the cases studied, but also the largest load drop at collapse. An all axially-stiff cylinder results in a small load drop at collapse, but a smaller buckling load.load and endshortening levels. However, for the cases considered here, the load drop is also larger when the overall axial stiffness is lower.
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