Design of sandwich-walled cylindrical shell structure with initial imperfections

Sandwich-walled cylindrical shell has been built with lattice-like stiffeners by adding another layer of skin in the inner surface of shell. Taking advantage of high mechanical property of lattice-like stiffeners, such as high specific stiffness, high specific strength etc., sandwich-walled cylindrical shell is studied for high load-carrying capacity in this paper. In this study, major parameters of sandwich-walled cylindrical shell is discussed for the effect of load-carrying capacity, and the imperfection sensitivity analysis of sandwich-walled cylindrical shells is carried out based on the eigenmode-shape imperfection approach and the single perturbation load approach. Comparing with the traditional stiffened cylindrical shell, the sandwich-walled cylindrical shell has a higher load-carrying efficiency. The reason of phenomenon is high bending stiffness of lattice-like stiffeners. And then, the optimization design of sandwich-walled cylindrical shells is carried out. It is results that optimum design of sandwich-walled cylindrical shell improved knockdown factor and load-carrying capacity. It can be concluded that sandwich-walled cylindrical shell is a potential structure to be more efficient structure in the future aerospace and aircraft designs.