基于模态综合法的起重机臂架模态特性分析

Analysis for modal characteristics of crane boom based on modal synthesis method

为了研究起重机组合臂架的计算模态特性以及变幅时由于几何形态的变化导致模态特性的动态变化,依据空间有限元法,采用Euler-Bernoulli梁单元建立门座起重机组合臂架的有限元模型;采用一种多子结构系统的模态综合法对臂架进行模态分析,研究了变幅时臂架的几何关系,最终得到起重机臂架的模态特性以及变幅时模态特性的动态变化过程。文中所述分析方法对于门座起重机这种特殊的组合臂架结构的结构设计和安全评估有一定借鉴意义。

To study the modal characteristics of crane combined boom , and dynamic change of modal characteristics caused by change of geometrical morphology at luffing , the finite element model for the combined boom of portal crane is built adopting Euler-Bernoulli beam unit based on the space finite element method; a multi-substructure modal synthesis method is employed to modal analysis of the crane boom in order to study geometrical relationship of the boom at luffing , and work out its modal characteristics and dynamic changing process.The mentioned method gives certain reference for structural design and safety evaluation of the special combined boom in the portal crane .