井筒对特大跨越输电塔风致响应的影响

Influence of shaft on wind-induced response of super-long span transmission tower

采用数值模拟方法研究井筒对特大跨越输电塔风致响应的影响,提出钢管混凝土杆采用钢管杆等代的等效建模方法,采用时域法和频域法研究有无井筒输电塔在顺线路和横线路方向的风致响应,最后将风振系数结果与规范规定值进行比较。研究表明:利用截面刚度等效原则进行钢管混凝土杆等效为钢管杆的方法是可行的;考虑井筒后输电塔的前两阶自振频率降低明显,输电塔的位移和加速度均增大;时域法和频域法的计算结果接近;有井筒输电塔的整体风振系数比无井筒输电塔大11%~15%;风振系数计算结果与《架空输电线路荷载规范》(DL/T 5551—2018)的规定值比较接近。

The numerical simulation method was used to study the influence of the shaft on the wind-induced response of the super-long span transmission tower.The equivalent modeling method of the concrete-filled steel tube rod using the steel tube rod was proposed.The time domain and frequency domain methods were used to study the wind-induced response of the transmission tower with or without wellbore in the direction of the line and the transverse line.Finally,the wind vibration coefficient results were compared with the specified values in the specification.The research shows that it is feasible to use the equivalent principle of section stiffness to equivalent the concrete filled steel tube rod to the steel tube rod.Considering that the first two natural frequencies of the transmission tower after the shaft are significantly reduced,the displacement and acceleration of the transmission tower are increased.The calculation results of time domain method and frequency domain method are close.The overall wind vibration coefficient of the transmission tower with shaft is 11%~15%larger than that of the transmission tower without shaft.The calculation results of the wind vibration coefficient are close to the specified values of the Load code for the design of overhead transmission line(DL/T 5551—2018).