中文摘要：

提出了一种可用于求解非线性约束优化问题的改进粒子群算法，并将其用于求解复合材料可靠性优化设计。在满足层合结构系统可靠度的情况下，以总厚度最小为目标函数，对复合材料的纤维方向角和厚度进行优化设计。结果表明，改进粒子群算法不但具备基本算法的简单易实现、需调整参数少的特性，而且能够在确保全局收敛性的基础上，快速搜索到高质量的优化解，对复合材料层合结构的可靠性优化设计十分有效。

英文摘要：

The paper proposed the improved particle swarm optimization （PSO） algorithm suitable for solving nonlinear constraint optimization problems and applied it to the reliability optimal design of composite materials. Under the condition that the reliability of the laminated structure of composite materials is satisfied, the paper took the smallest possible total thickness as the objective function and carried out the optimal design of the fibre directional angle and thickness of composite materials. The design results indicate the improved PSO algorithm is simple and easy to implement, needs fewer adjustment parameters, guarantees global convergence and rapid search for quality optimal solutions, thus producing good effects for the reliability optimal design of the laminated structure of composite materials.