Imperfection-insensitive thin wavy cylindrical shells under bending: Effect of local radius of curvature on buckling and imperfection-sensitivity.

The imperfection-sensitivity of thin cylindrical shells has long been an obstacle for their optimal applications. To nullify this behavior, a conservative knock-down factor method is utilized for the design of thin cylindrical shells. Alternatively, stiffeners are also used to increase their capacity and to reduce the imperfection-sensitivity. We explore wavy cross-sectional thin cylindrical shells under bending to investigate the impact of imperfections on their load carrying capacity. We found that thin wavy cylindrical shells are insensitive to imperfections under bending in contrast to thin circular cylinders. This insensitivity is achieved by reducing the local radius of curvature and consequently, the effective radius of the cylindrical shell is reduced. This way cylindrical shells become less sensitive to imperfections and increase their load carrying capacity.