Structural Optimization Design of a Typical Adhesive Bonded Honeycomb-Core Sandwich T-joint in Side Bending Using Multi-Island Genetic Algorithm

Sandwich structure T-joints are increasingly broadly applied in aviation and aerospace industries due to the need for lightweight design. This paper deals with the lightweight optimization of a typical adhesively bonded Nomex honeycomb-core sandwich T-joint in side bending load, considering the strength constraints. The optimization problem, with discrete and continuous design variables, is a compound optimization problem involving size optimization for the whole structure and stacking sequence optimization for multiple variable-thickness composite laminates. A self-adjusted parametric modeling with user-defined suppression process is proposed. An integrated combination of progressive damage model methodology, self-adjusted parametric modeling with user-defined suppression process and multi-island genetic algorithm is applied for the optimization problem. The optimization result showed 30.75% weight reduction compared to the original T-joint configuration. On the basis of history data, we investigate the correlations between design variables and concerned constraint variables.