Optimization of structural gradient parameters of circular sandwich plates with a bio-inspired core

A circular sandwich plate featuring a bio-inspired gradient core was designed based on the structural characteristics of the Royal Water Lily (RWL), and its energy absorbing performance under blast loading was thoroughly investigated. An optimization-based approach combined with computational simulations was used to explore the optimal configuration of the structure, incorporating both out-of-plane and in-plane gradient designs under a constant mass constraint. These gradient models were developed by varying the wall thickness at different locations within the core to achieve locally differentiated relative densities. Three key parameters were selected as the design objectives: core energy absorption (EC), total model energy absorption (ET), and central displacement of the bottom face sheet (DIS). Response surface models were constructed using simulation data generated through the optimization algorithm, enabling the determination of optimal configurations for each design objective. Additionally, the effects of density gradients on the structural response parameters were analyzed in detail. This study presents a novel methodology for the design of gradient sandwich structures subjected to dynamic loading.