桥式起重机箱型主梁周期性拓扑优化设计

Periodic Topology Optimization of the Box-type Girder of Bridge Crane

桥式起重机主梁长度方向尺寸远大于高度和宽度方向,常规的拓扑优化方法无法获得清晰的、周期性的拓扑形式或求解困难。为了实现桥式起重机主梁的拓扑优化,得到具有周期性的、易于加工的结构拓扑形式。把主梁优化域划分成若干个子域,构建子域与优化域之间的关系。建立以优化域内单元相对密度为设计变量、以体积约束下最小柔度为目标函数的主梁周期性拓扑优化数学模型。在主梁强度和静态刚度准则下开展主梁周期性拓扑优化应用研究。结果表明,在优化过程中,各子域内同时出现孔洞,且具有周期性。直到周期性拓扑优化结束,获得具有类似'桁架式'结构的拓扑形式。子域数目取值不同时,均可获得周期性的拓扑形式,且具有良好的一致性和工艺性。为桥式起重机结构轻量化研究提出一种可行的方法。

The length of box-type girder of bridge crane is much greater than the height and width. It is difficult to obtain a solution or a clear and periodic topology configuration using conventional algorithm. In order to obtain a periodic structure which is easy to manufacture, periodic topology optimization is applied to the lightweight design of bridge crane’s girder. The optimization domain of girder is divided into some sub-domains and the relation between sub-domains and optimization domain is structured. The mathematical model of girder for periodic topology optimization is built, in which mean compliance is taken as objective function under volume constraint condition. Periodic topology optimization of girder is researched under the strength and static rigidity criterion. Results show that periodic holes are appeared in sub-domains during optimization process. Until periodic topology optimization is over, a similar trussed topology configuration is obtained. Even when the number of sub-domains is different, periodic topology configuration which has a good consistency and manufacturability is achieved. A feasible approach is proposed aiming at lightweight design for bridge crane.