覆冰导线舞动作用下杆塔结构破坏过程数值模拟

Numerical Simulation of Transmission Tower Structural Damage under Action of Icing Conductor Galloping

为考察输电杆塔在覆冰舞动工况条件下破坏过程及倒塌机理,以110kV肖湖432线输电杆塔为例,基于有限元软件MIDAS建立杆塔结构模型,利用Matlab模拟出导线覆冰舞动荷载波形,在MIDAS中建立时程荷载函数,对杆塔结构施加导线舞动荷载进行动力时程分析,并对杆塔结构的破坏机理、破坏形态及塔材变形的发展情况进行了模拟分析。结果表明,杆塔的破坏是由于部分交叉斜撑发生较大变形,使主材侧向约束显著弱化,随着时间的推移在杆塔的薄弱位置发生破坏,并最终导致倒塔;数值模拟结果与杆塔结构实际的破坏形式相符,验证了该方法的正确性。

In order to investigate the damage process and collapse mechanism of transmission tower under operating conditions of icing galloping, taking 110 kV Xiaohu 423 transmission tower for an example, finite element software MI- DAS is used to establish structure model of poles and towers. And then the galloping load waveform of icing conductor is simulated with Matlab. At the same time, time-histories load function is established with MIDAS and it implements dy namic time histories analysis under action of galloping load for tower structure. Finally, the failure mechanism and failure mode of the tower structure and the deformation development of tower material are simulated and analyzed. The results show that part of large cross-bracing deformation leads to tower destruction and makes the lateral restraint of main material weakened significantly; with the time-lapse, the weak position of the tower appears damage, and eventually it collapses; numerical simulation result is consistent with the actual destruction of the tower structural form. So, the correctness of the method is verified.