基于拓扑优化的钢桥结构合理构型研究

Research on the Optimal Configuration of Steel Bridge Based on Topology Optimization

采用拓扑优化的方法,对钢桥结构的合理构型设计进行了研究.首先,基于Hypermesh建立了一个矩形区域的初始有限元模型,在赋予钢材参数后,进行了静力分析.然后,对模型设定可设计区域,以结构刚度为约束条件,结构总质量最小为目标函数,应用OptStruct对钢桥进行了拓扑优化.最后,提炼结构优化后的计算模型,重新进行有限元静力分析,得到结构的位移和应力分布,并将优化结果与初始模型的结果进行了对比分析.研究结果表明:优化后的结构合理构型表现为拱和桁架的组合结构,通过优化设计,在结构刚度和强度基本不变的情况下,钢桥结构的总质量可降低54%.该方法应用于一个旧桥加固工程中,有效性和可行性得到了验证.

The optimal configuration design of steel bridge was studied by using the method of topology optimization in this paper. Firstly, an initial finite element model with rectangular area was constructed based on Hypermesh, and the linear static analysis of the model was carried out. Then the designable area of the steel bridge was set up. After structural stiffness was set as constraint condition and the minimum total structural mass was set as objective function, the topology optimization of the steel bridge was carried out by Optistruct. Finally, the optimized calculation model was refined, and the finite element static analysis was carried out again. The displacement and stress distribution of the structure were obtained, and the optimized results were compared with the results of the initial model. The analysis results show that the optimal structural configuration of the steel bridge is a combination structure of arch and truss. After optimization the structural total mass is decreased by 54% with the almost same structural stiffness and strength.The method was applied to an old bridge reinforcement project and its effectiveness and feasibility was verified.