韩军科，杨靖波，杨风利
（中国电力科学研究院，北京100192）

[摘要] 2008年初电网冰灾给我国输电线路造成了严重的破坏。500kV输电线路受损严重，由于直线塔承受覆冰不平衡张力的能力远小于耐张塔，导致双回路输电线路的破坏绝大部分是由双回路直线塔的倒塌引起的。为了弄清冰灾区双回路直线塔的受力特点，选取浙江省冰灾区500kV线路中的双回路直线塔进行均匀覆冰荷载和不均匀覆冰荷载作用下铁塔覆冰破坏模式分析。通过破坏模式的分析，确定双回路直线塔覆冰荷载作用下的起始破坏部位，提出冰灾区双回路直线塔加固补强的措施。研究结果为我国冰灾区双回路直线塔的设计和加固补强提供参考依据。
[关键词] 输电线路；双回路直线塔；覆冰不平衡张力；覆冰破坏模式；加固补强

    Analysis of failure mode on fouble circuit tangent towers in ice disaster area
    Han Junke,  Yang Jingbo,  Yang Fengli
    ( China Electric Power Research Institute, Beijing 100192, China)

Abstract: The ice disaster of power grid in early 2008 caused by ice coating in transmission lines caused great damage in China, and the 500kV transmission lines damaged seriously. Because strain towers can withstand greater unbalanced tension for ice coating than tangent towers, so most destroy of double circuit transmission lines was caused by the collapse of double circuit tangent towers. In order to seek the performance and the characteristics of double circuit tangent towers under ice coating, the failure mode of double circuit tangent towers on the uniform ice formation and non-uniform ice formation was analyzed, which were selected from the 500kV transnussion lines in ice disaster area of Zhejiang province. The initial failure position of double circuit tangent towers under ice coating was confirmed and the reinforcement and strengthening measures were proposed by the failure mode analysis. The research results provide very important reference for the double circuit tangent towers design and strengthening in ice disaster area.
Keywords: overhead transmission line; double circuit tangent tower; unbalanced tension for ice coating; failure mode for ice coating; reinforcement and strengthening method