Theoretical analysis is attemped for the effect of axisymmetrical prebuckling deformation on the compressive buckling load of anisotropic circular cylindrical shells. Compressive buckling tests of two types of filament-wound graphiteepoxy cylindrical shells and four types of laminated ones were carried out. The stacking sequences of four types of lamination are [20°, -20°, 90°], [0°, 45°, -45°, 90°], [30°, -30°, -30°, 30°, 90°, 90°] and [0°, 60°, -60°, -60°, 60°, 0°], and those of two types of filament winding are [±20°, 90°] and [90°, ±20°] where the top is inside, respectively. The calculated buckling loads of these test cylinders have disclosed the property that the prebuckling deformation raises the buckling load except for the No.3 test cylinder of which buckling mode in the linear theory is axisymmetrical. This property is contrary to the one known for isotropic cylinders. Some analytical studies are carried out for this reason. For laminated cylinders, a good agreement is observed between theoretical and experimental buckling loads. In the case of filament wound and 3- and 4-layer cylinders, after the end-shortening was removed, they returned to a perfect cylinder, as the buckling deformation was almost elastic. The buckling load of the filament-wound cylinder is lower than that of the laminated one with the same fiber direction.
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