桥式起重机起吊过程的动力学分析

The dynamics analysis of the bridge crane in the hoisting process

桥式起重机在起吊过程中,结构动力学特性复杂。以主梁薄弱截面(跨中)为研究对象,运用结构动力学理论,从桥式起重机起吊过程的特征出发,将起吊过程简化为二质量二自由度系统,并确立系统主要参数。运用该模型建立起吊过程各阶段系统的运动微分方程。最终求解得出起吊过程跨中的动位移时间函数,通过动位移时间函数得出预张紧阶段结束时间和最大动位移值。最后以某起重机为实例验证了动力学分析结论。

For the bridge crane in the hoisting process,the structure dynamics characteristic is complex. The main beam mid-span,the most dangerous beam section,was selected as the research object. According to the hoisting characteristic in the hoisting process,the structural dynamics theory was used to simplify the hoisting process to a two masses two degrees of freedom system. The main system parameters were got,and the differential equation was built in the hoisting process. At last,dynamic displacement time function in the main beam mid-span was got. Both the ending time in the pretensioner phase and maximum dynamic displacement can be got by the dynamic displacement time function in the hoisting process. Finally,the results of dynamics analysis were checked by a practical crane.