覆冰区输电线路弃线措施安全性研究

Safety Research on Wire Removal of Transmission Tower-line Systems in Icing Areas

建立了某山地覆冰区输电线路有限元分析模型,建立了塔线体系在覆冰和弃线措施作用下的结构体系反应分析方法。以我国南方山地覆冰区的某耐张段输电线路为实际工程背景,研究了覆冰后拆除地线对输电杆塔服役安全性的影响。结果表明:覆冰弃线措施可以有效减小输电塔线体系的服役荷载,提高关键杆塔的强度储备和安全性。拆除地线将引起杆塔所受张力减小,其它位置的导地线承载力状况基本不变,变化幅度不超过3%。拆除覆冰地线只能提高输电杆塔的服役安全性,但对导地线承载力影响很小。

The finite element model of a transmission tower-line system in a tension resistance section in icing mountains is first established.The dynamic analytical approach of the transmission tower-line system under icing load and wire-removal is developed.A real transmission tower-line system in the southern icing mountains in China is taken as an example to investigate the effect of the wire removal on safety performance of tower-line system.The made observations indicate that the wire removal can be used to effectively reduce the service loads of the system and to increase the strength reserve and safety.The removal of iced ground wires induces the reduction of tensile forces acting on the transmission tower,while the force-bearing capacity of other adjacent wires and conductors remain almost unchangeable,the change is within 3%.Therefore,the wire removal can only improve safety performance of the tower,instead of affecting the force-bearing capacity of transmission lines.