基于响应面分析法的桥式起重机主梁轻量化设计

Lightweight design of bridge crane girder based on response surface analysis

针对传统优化方法在起重机主梁结构优化方面存在效率低、精度不高的问题,提出了基于响应面模型的结构优化方法。在满足变形和应力的条件下,降低安全系数以优化结构和进行轻量化设计。将主梁模型适当简化后,导入有限元分析软件Workbench中对桥式起重机主梁进行静力学分析,得到最大变形量和应力集中的结构位置。将对起重机主梁最大应力影响较大的上下盖板厚度、腹板间距、腹板高度和大隔板厚度等5个结构尺寸设为参数,以质量最小为优化目标,约束最大应力和最大变形以及结构尺寸,建立目标函数的优化数学模型。以响应面分析法对起重机主梁进行轻量化设计,通过中心复合设计产生45组样本点,优化后主梁质量减少17.14%。

Aiming at the problems of low efficiency and low precision in the optimization of crane girder structure with traditional optimization methods,a structural optimization method based on response surface model is proposed. Under the conditions of satisfying deformation and stress,reduce the safety factor to optimize the structure and carry out lightweight design. After the main girder model is appropriately simplified,it is imported into the finite element analysis software Workbench to perform statics analysis on the main girder of the bridge crane to obtain the structural position of the maximum deformation and stress concentration. The five structural dimensions of the upper and lower cover thickness,web spacing,web height and large diaphragm thickness that have a greater impact on the maximum stress of the crane main beam are set as parameters,and the minimum mass is the optimization goal to constrain the maximum stress and maximum deformation As well as the size of the structure,an optimized mathematical model of the objective function is established. The light-weight design of the crane’s main girder was carried out by response surface analysis,and 45 sets of sample points were generated through the central composite design. After optimization,the mass of the main girder was reduced by 7. 14%.