考虑塔-线耦合作用的输电塔体系风振系数研究

考虑塔-线耦合作用的体系风振响应以及对应情况下的输电塔等效风荷载的风振系数取值是输电塔抗风设计的基础,结合某220kV输电线路一塔两线实例,通过气弹性风洞试验和有限元数值模拟的方式,研究输电塔在考虑导、地线耦合作用下的风振响应规律,计算其对应的输电塔等效风荷载的风振系数,并与我国现行规范中的相关取值进行对比,结果表明:横担和输电线的存在使得塔身中上部的风振系数明显增大,在进行输电塔设计时需考虑其影响;建议采用《建筑结构荷载规范》(GB 50009—2012)和《高耸结构设计规范》(GB50135—2006)来计算风振系数时,对横担位置进行修正或单独考虑,而《架空输电线路荷载规范》(DLT5551—2018)更适用于输电塔类结构的风振系数的计算。

A Study on the Wind Vibration Coefficient of Transmission Tower System Considering Tower-Line Coupling Effect

The wind-induced vibration response of a system considering tower-line coupling and the vibration coefficient of the equivalent wind load of transmission tower are the basis of the wind-resistant design.This paper combines a 220 kV transmission line with one tower and two lines.Through the method of air-elastic wind tunnel test and finite element numerical simulation,the wind-induced vibration response of transmission towers considering the coupling effect of conductor and ground wire is studied,and the wind vibration coefficients of the corresponding transmission tower equivalent wind load are calculated.The relevant values in China’s current codes are compared and analyzed.The result shows the presence of cross arms and transmission lines significantly increases the wind vibration coefficient in the upper part of the tower body,and the influence needs to be considered when designing the transmission tower.It is recommended to use the Load Code for the Design of Building Structures(GB 50009—2012)and Code for Design of High-Rising Structures(GB 50135—2006)to calculate the wind vibration coefficient separately to consider or correct the cross arm position,and the Load Code for Design of Overload Transmission Line(DLT 5551—2018)is more suitable for the calculation of the wind vibration coefficient of transmission tower structure.