横向振动下的螺栓连接松动分析

Analysis on Bolt Connection Looseness under Transverse Vibration

针对螺栓连接结构受横向载荷时的松动问题,建立横向载荷作用下的螺栓连接平板结构有限元模型,并考虑螺栓材料塑性影响,分别探究平板在横向载荷作用下螺栓的初始预紧力、载荷的幅值及频率对螺栓松动的影响。结果表明:初始螺栓预紧力增大,则振动过程中螺栓预紧力下降速度降低,对螺栓防松有利;载荷振幅是影响螺栓松动的主要因素,载荷振幅由0.2 mm增大至0.3 mm时,螺栓预紧力减小了40%;载荷频率对预紧力下降影响不明显。仿真结论与实验结果规律具有较好的一致性,从而验证了分析模型的有效性。

With the aim at the looseness of transmission tower bolted structure under transverse load,a finite element model of bolted plate structure under transverse load is established,and in consideration of the plastic influence of bolt material,the effects of bolt initial preload,load amplitude and frequency on bolt looseness under the influence of transverse load are explored.The results show that when the initial bolt pretightening force increases,the decreasing speed of the bolt pretightening force decreases during the vibration process,which is beneficial to the bolt loosening prevention.As the load amplitude,being the main factor affecting the bolt loosening,increases from 0.2 mm to 0.3 mm,the bolt preload is reduced by 40%,and the load frequency has no obvious effect on the decrease of the preload.The simulation results are in good agreement with the experimental ones,and the effectiveness of the analysis model is verified.