基于极限承载力分析的覆冰输电塔可靠性评估  

Reliability Evaluation for Iced Tower Based on Ultimate Bearing Capacity Analysis

作　　者：姚陈果[1] 李宇[1] 周泽宏 李成祥[1] 张磊[1] 左周[1] 

机构地区：[1]重庆大学输配电装备及系统安全与新技术国家重点实验室,重庆400030 [2]重庆送变电工程公司,重庆400015

出　　处：《高电压技术》2013年第11期2609-2614,共6页High Voltage Engineering

基　　金：国家重点基础研究发展计划(973计划)(2009CB724502);输配电装备及系统安全与新技术国家重点实验室自主研究项目(2007DA10512711207)~~

摘　　要：针对目前输电杆塔结构可靠性分析存在的难点,将基于有限元非线性屈曲分析得到的结构极限承载力与杆塔可靠性分析相结合,从结构整体响应出发对覆冰作用下杆塔的安全性进行了评估。选取南方某段输电线路为分析对象,建立了该段线路的输电塔-线体系有限元模型并进行分析,找出该段线路的薄弱杆塔。然后,以材料的弹性模量和强度为基础,循环计算得到薄弱杆塔极限承载力的样本,以该样本得到杆塔的极限承载能力的分布类型及其参数。最后运用一次二阶矩法,结合极限状态方程计算了薄弱杆塔在不同工况下的可靠度。实例分析证明该方法避免了基于失效模式法求可靠度带来的困难。For solving the difficulties in reliability analysis of transmission towers, through combining the ultimate bearing capacity obtained from non-linear buckling analysis with the reliability analysis of tower, we evaluated the safety of iced towers from the perspective of integral structural response. Choosing a certain part of the transmission lines in north China as the example, we established a tower-line finite element model of the line, and obtained the weakest tower of the line through calculations using the model. Then, using the elastic modulus and strength of the tower material, we calculated a sample of the ultimate bearing capacity of the weakest tower. Based on the sample, the type of distribution and the parameters of the ultimate bearing capacity were acquired. Finally, using the firstorder second-moment method, the reliability of the weakest tower under different work conditions was calculated. An instance analysis proves that using the proposed method can effectively avoid difficulties existed in the failure- mode-based methods.

关 键 词：输电塔-线体系 覆冰 一次二阶矩法 可靠性 极限承载力 博弱杆塔 

分 类 号：TM753[电气工程—电力系统及自动化]