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伸缩臂式起重机在带载回转制动时,侧向动载力很大,据统计由此而产生的钢结构破坏事故占全部破坏事故的18%。如何计算这一起制动惯性力,是一个重要研究课题。假若把起重机视为刚体,只要知道起动加速、制动减速所经历的时间以及起重机运动部分的质量、稳定运行阶段的速度,那么,这种动载是容易掌握的;然而,一台汽车起重机是一个具有分布质量和集中质量的弹性体,而这些质量之间是弹性联系的。实际上,原来处于平衡(静止或匀速运动)状态的系统,一旦承受一个恒定的或变动骤加载荷之后,它立刻进入某一新平衡状态的复杂振动之中,动载的大
Telescopic cranes have a large dynamic load in the lateral direction when the regenerative brakes are loaded. According to statistics, the steel structure damage accidents account for 18% of all accidents. How to calculate this together with braking inertial force is an important research topic. If the crane is regarded as a rigid body, as long as it knows the acceleration of the start, the time it takes for the brake to decelerate, the quality of the moving part of the crane, and the speed of the stable operation phase, then this dynamic load is easy to grasp; however, a truck crane is An elastic body with distributed quality and concentrated quality, and these qualities are elastically linked. In fact, once the system is in equilibrium (static or uniform motion), once it is subjected to a constant or variable sudden load, it immediately enters into a complex vibration of a new equilibrium state.