Buckling Behavior of Compression-loaded Advanced Grid Stiffened Composite Cylindrical Shells with Reinforced Cutouts

In this paper, the buckling behavior of an advanced grid stiffened (AGS) composite cylindrical shell with a rectangular cutout is systematically investigated using the finite element method. The effects of reinforcement dimension of cutout on the non-linear response of the AGS composite cylindrical shell are described. The simulational results illustrate the complex non-linear response of a compression-loaded AGS composite cylindrical shell with an unreinforced cutout. In particular, a local buckling response occurs on the shell near the cutout which is caused by local skin deformations near the cutout. In general, reinforcement around a cutout in a compression-loaded AGS composite cylindrical shell can eliminate the local buckling response near the cutout and increase the global collapse load of the shell. However, simulational results illustrate that which reinforcement configurations can cause an unexpected increase in the magnitude of local deformations in the shell and cause a reduction in the global collapse load. A parameter study, including the orientation, thickness and size of cutout reinforcement in the AGS composite cylindrical shells, was conducted to improve the buckling response characteristics by determining a set of appropriate parameters.