特高压单柱拉线塔风振系数研究

Analysis on wind-induced vibration coefficient of UHV single-mast guyed tower

具有高柔性的特高压单柱拉线塔对风荷载十分敏感,风振系数的确定是其设计和应用的基础。建立了特高压单柱拉线塔塔线体系的有限元模型,阐述了基于振型叠加法的风振系数计算方法,考虑结构的前两阶振型的影响,基于时程分析的数据计算了单柱拉线塔的风振系数。结果表明:主柱上存在横隔材的位置风振系数会发生突变;时程分析得到的加权风振系数与按照荷载规范计算得到的加权风振系数较为接近;等效静力风荷载作用下,迎风侧主材轴力与风振响应的最大值较为接近,且大于平均风下主材的轴力。

The high-flexible UHV guyed single-mast tower is sensitive to wind load,the determination of wind-induced vibration coefficient is the basic of its design and application. The finite element model of UHV guyed single-mast transmission tower-line system was build. The computing method of wind-induced vibration coefficient based on mode superposition method was stated. In consideration of the influence of the first and second mode of the structure,the wind-induced vibration coefficient of guyed tower was calculated based on the data of time history analysis. Result shows that the wind-induced vibration coefficient changes suddenly on transverse. The weighted average of wind-induced vibration coefficient calculated by time history analysis is very close to that according to GB 50009—2012. Windward leg member's axial force under equivalent static wind load is very close to the maximum of wind-induced response and it' s bigger than that under mean wind load.