变电构架避雷针结构的风致动力响应与加固分析  

Wind-induced Dynamic Response and Reinforcement Analysis of Substation Framework with Lightning Rod

作　　者：赵桂峰[1] 刘冉 王朝华 陈怡文 ZHAO Guifeng;LIU Ran;WANG Chaohua;CHEN Yiwen(School of Civil Engineering,Zhengzhou University,Zhengzhou 450001,China;State Grid Henan Electric Power Corporation Electric Power Research Institute,Zhengzhou 450052,China)

机构地区：[1]郑州大学土木工程学院,郑州450001 [2]国网河南省电力公司电力科学研究院,郑州450052

出　　处：《结构工程师》2019年第5期196-205,共10页Structural Engineers

基　　金：国家自然科学基金项目(51108425);国网河南省电力公司科技攻关项目。

摘　　要：以某500 kV变电站构架避雷针结构为背景,建立了典型构架避雷针结构的有限元模型,对其进行模态分析、频域内的谐响应分析和不同风向角下结构的动力响应分析并与单根避雷针进行了对比。结果表明:设置避雷针的变电构架模态频率分布较为密集,振型主要以避雷针的局部振动为主。在设计风荷载作用下,典型构架避雷针整体结构的中间避雷针受力较为不利,避雷针和横梁的相贯T型节点处以及中间变截面处应力水平较高,说明其构造不合理,需要对上述部位进行加固处理。对比加固前后结构的风振动力响应可知,在T型节点处设加劲肋可有效减轻避雷针和横梁相贯节点处的应力集中现象。对比相同工况下结构的动静力计算结果,建议按照现行规范设计构架避雷针结构时,将拟静力分析结果乘以一个动力放大系数,以策安全。The finite element models of typical a framework structure with lightning rods were established based on a 500kV substation frame lightning rod.The modal analysis,harmonic response analysis within the frequency domain,dynamic response of structure under different wind directions were performed,also compared with the single lightning rod.The results show that,the modal frequency distribution of the with lightning rods is more intensive.The middle lighting rod is the most unfavorable when the whole structure under design wind load;the stress at the T-node and middle variable cross section of lightning rod is comparative high;this illustrates that the structure is not reasonable and should be reinforced at above parts.Comparing the Wind-induced dynamic response results before and after reinforcement,it is obvious that the stiffener at the T-node can significantly reduces the stress concentration at the intersecting nodes.Comparing the static and dynamic results under the same conditions,it is suggested that the quasi-static results should be multiplied by a dynamic amplification factor during design of the lighting rod structure according to the current specifications.

关 键 词：变电构架避雷针 风致动力响应 相贯节点 

分 类 号：TM8[电气工程—高电压与绝缘技术]