塔身标准节连接螺栓预紧力变化宏观表征研究

Macroscopic Characterization of Preload Change of Connecting Bolts in Standard Joints of Tower Body

塔式起重机(简称塔机)塔身标准节连接螺栓松动是塔机倒塌事故的重要原因之一。以塔式起重机塔身不同位置标准节连接螺栓松动行为为研究对象。采用ANSYS软件中命令流建模方式建立两节塔身标准节实体模型,标准节不同构件之间的实体连接使用NUMMRG、CP等耦合方式实现,使用预紧单元施加标准节连接螺栓预紧力。用改变预紧力大小的方法模拟连接螺栓松动现象,研究连接螺栓松动对标准节主肢顶端位移的影响。通过研究塔身不同位置标准节单个螺栓预紧力变化的宏观表征,获得塔身标准节在塔身不同位置的主肢特征点位移变化规律曲线,为塔身标准节位移影响曲线反推螺栓松动的研究打下基础。

The looseness of the connecting bolts of the standard joints of the tower crane is one of the important reasons for the collapse of the tower crane.In this paper,the loosening behavior of connecting bolts of standard joints in different positions of tower crane body is studied.The command flow modeling method in ANSYS software is used to establish the solid model of two standard joints of the tower body.The solid connection between different components of the standard joints is realized by NUMMRG,CP and some other coupling methods.The preload elements are used to apply the preload force of the standard joint connecting bolts.By changing the preload to simulate the loosening of the connecting bolts,the influence of the loosening of the connecting bolts on the top displacement of the main limb of the standard joint is studied.By studying the macro characterization of the changing of the preload of a single bolt of the standard joint at different positions of the tower body,the displacement changing curve of the main limb characteristic points of the standard joints at different positions of the tower body is obtained.This work has provided a method to reverse the looseness of bolts according to the influence curve of the displacement of the standard joint of the tower body.