基于一种新的应力准则的渐进结构优化方法

根据工程优化设计中最关注的材料利用率和最大应力最小化问题，引入且导出了应力评估参数，并基于此参数和单元的应力水平，提出了一种新的应力准则．该方法能有效缓解在删除无效材料时可能导致的应力集中．用两种不同方法对悬臂梁进行了优化设计，实例说明这一方法比传统的基于应力的渐进结构优化方法更为有效．

New Stress Criteria Based on Algorithm for Evolutionary Structural Optimization

According to stress minimization and material utility,which are two major aspects of structural optimization in a wide range of engineering designs,a stress estimate parameter is introduced and derived in this paper.Then a new stress criterion is presented for the problems of minimizing the maximum stress while low-stressed elements are removed.On the basis of finite element analyses stresses and stress estimate parameters,a new evolutionary structure optimization method and its procedure are proposed.During structural topology optimization,it can deal with the effect of both local von Mises stress level and structural intrinsic cross property.Comparison between two different methods on a cantilever optimization is made.The numerical example demonstrates that the proposed method is of great capability in reducing maximum von Mises stress,and is more valid and effective than the conventional evolutionary structural optimization(ESO) method based on stresses.