输电塔线体系舞动响应特征试验

Experimental study on features of galloping response of tower-line system for transmission

为深入考察输电塔线体系在覆冰导线舞动作用下的动态响应特征,以在舞动事故中横担严重破坏的某塔线体系为研究对象,基于模型动力相似原理,设计制作了弹性边界条件下的大比例输电塔节段模型和能够模拟不同覆冰参数的导线模型,并研制开发了模拟覆冰导线舞动的试验加载装置.在此基础上,在试验室条件下再现了导线舞动时的动张力和运动特征,并进行了不同参数下的输电塔线体系舞动试验,研究了覆冰厚度、舞动幅值以及频率对塔线体系响应特征的影响.试验结果表明:导线舞动不会激发输电塔的共振;塔线体系舞动响应会随舞动幅值、覆冰厚度和舞动频率的增大而增大;与导线动张力和构件应变相比,输电塔的振动响应对舞动幅值和频率的变化更为敏感.

To investigate the dynamic responses of transmission tower-line systems caused by conduc- tor galloping, taking a strain resistant corner tower as a prototype with cross arm seriously damaged under iced conductor galloping disaster, a tower segmental model with elastic boundary condition and conductor model of different ice thickness were founded by the similarity theory of dynamic model, and the vibration experimental equipment used to simulate galloping responses of iced-conductor was developed at the first time. On this basis, the dynamic tension and vibration features of galloping con- ductor were reconstructed under the laboratorial conditions. Then the galloping experiment of trans- mission tower line was carried out, and the effects of ice thickness, galloping amplitude and frequency on dynamic response of transmission tower-line system were discussed. The results shows that the galloping of iced-conductor cannot result in the resonance of transmission tower, and the galloping re- sponse of the tower-line coupling system increases with the raise of ice thickness, the galloping ampli- tude and frequency. Furthermore, compared with dynamic tension and strain of members, the dynam- ic response of transmission tower is more sensitive to the vibration of the galloping amplitude and fre- quency.