连体构架避雷针风振计算的简化方法  

A Simplified Method for the Dynamic Calculation of Wind-Induced Responses of Substation Frame Lightning Rods

作　　者：董新胜 张军锋[2] 马勤勇 杨洋 管品武[2] DONG Xinsheng;ZHANG Junfeng;MA Qinyong;YANG Yang;GUAN Pinwu(Xinjiang Electric Power Research Institute,Urumqi 830011,Xinjiang,China;School of Civil Engineering,Zhengzhou University,Zhengzhou 450001,Henan,China)

机构地区：[1]国网新疆电力公司电力科学研究院,新疆乌鲁木齐830011 [2]郑州大学土木工程学院,河南郑州450001

出　　处：《力学季刊》2021年第1期187-196,共10页Chinese Quarterly of Mechanics

基　　金：国家自然科学基金(51508523)。

摘　　要：为简化构架避雷针风振时域计算从而有效降低计算耗时,以单跨和三跨构架避雷针结构为例,根据构架体系的结构特性和风振特点,提出一种简化计算方法,即对每个塔架单独建模并考虑结构刚度和质量系统的一致性和横梁荷载的等效加载,从而对每个塔架单独进行动力计算,并对这种简化方法的合理性进行了验证。研究发现,构架避雷针的频率较小,风振效应较为显著,但在各方向均以一阶振型为绝对主力;构架避雷针的塔架在平面外的荷载耦联效应极小,平面内也仅表现有位移均值的耦联效应:这两个结构特性也为风振简化计算提供了便利。对每个塔架的简化模型,通过在塔架与原横梁连接处设置弹簧和附加质量来实现对原结构一阶振型的等效,并通过影响线法将横梁分布风荷载等效为塔架的集中荷载。由此简化方法所得的结构风振静动力响应结果均与原始结构有良好一致性,并且计算效率得以显著提升。The study was initiated for a simplified method for the dynamic calculation of wind-induced responses in time domain of substation frame lightning rods,aiming to reduce the time consumption.For single-span and three-span frame lightning rod structures,a simplified wind-induced response calculation method was proposed according to the structural properties and the characteristics of the wind-induced vibrations.In the simplified method,each tower in the frames is modeled and calculated independently.The simplified model reserves the same structure properties and equivalent beam load,thus generates results that can accurately reflect the original wind dynamic effects of the global structure.After the illustration on the simplification process,both the results got from the simplified and the global model are presented for validation.The results show that the resonant component is prominent due to the low frequency which is dominated by the first mode in each direction.The coupling effects between the towers are negligible in the out-plane direction but impact just the mean displacement in the in-plane direction.These two characteristics provide convenience for the calculation.For each tower model in the simplified method,an additional mass and string are added to the joint of frame,whose values are determined according to the mode shape and frequency of the first mode.Moreover,the distributed wind load on the beam are replaced by a concentrated force at the joint,whose value is determined according to the influence function.The results from the simplified and the traditional methods show little deviation from each other and the simplified method exhibits tremendous efficiency.

关 键 词：构架避雷针 风振响应 时域计算 简化计算 风振特性 耦联效应 

分 类 号：TU973[建筑科学—结构工程]