桥式起重机主梁自适应多目标动态优化

Adaptive Multi-Objective Dynamic Optimization of the Main Beam of Bridge Crane

以通用型双梁桥式起重机为对象,对主梁进行结构优化设计,采用一种新的将Kriging响应面与多目标遗传算法相结合的优化方法,相比一般多目标遗传算法,计算成本更低,能更加快速地找到第一个Pareto前端解。考虑了结构动态性能,即主梁结构的垂直自振频率应尽量较低;简化双梁结构,以单个梁结构为分析对象,提高了计算效率。优化后的起重机相比原始设计质量减轻了7.61%,垂直自振频率为5.96Hz,最大应力98.15Mpa,增大了13.54%,最大变形36.38mm,增加了4.55%,满足了静刚度和强度条件,说明优化是有效的。

Inthis paper,a new method which is combining Kriging response surface with multi-objective genetic algorithm was used to optimize the structure of the main beam of double-beam bridge crane.Compared with the general multi-objective genetic algorithm,the computing cost is lower and the first Pareto front end can be quickly found.Considering the dynamic performance of the structure,the vertical vibration frequency of the main beam structure should be as low as possible.Simplifying the double beam structure and using the single beam structure as the analysis object can improve the calculation efficiency.Compared with the original structure,the quality of optimized design is reducedby 7.61%,the vertical natural frequency is 5.96Hz,the maximum stress is 98.15MPa,increased by 13.54%,the maximum deformation is 36.38mm,increased by 4.55%,whichcan satisfy the static stiffness and strength conditions,provethat the optimization is effective.