Blast Resistance of Confined Multilayer Graded Corrugated-Core Sandwich Cylindrical Shells.

A graded multilayer corrugated-core sandwich cylindrical shell is proposed as an innovative blast-resistant container to resist internal blast loading. The blast resistance performance of both uniform and graded multilayer corrugated shells was systematically investigated through finite element analysis. Results revealed that sandwich shells featuring an internally thick and externally thin core wall arrangement exhibited superior blast resistance. This configuration optimally aligns with the natural attenuation behavior of blast pressure, which gradually decreases from inner to outer layers during multilayer core collapse. Structures with core layer height gradients, characterized by internally high and externally low layers, also demonstrated enhanced performance under blast loading. While increasing the gradient magnitude generally improves blast resistance, this benefit diminishes with escalating blast intensity. Notably, wall-thickness-graded structures consistently outperformed height-graded configurations. Finally, a radial basis function surrogate model combined with adaptive simulated annealing optimization was employed to identify optimal thickness-graded cylindrical shell configurations tailored for either maximum blast resistance or minimum structural mass.