山区微地形中风向对铁塔塔身风荷载的影响与修正

For transmission lines passing through micro-topography areas, the influence of the wind speed acceleration effect should be considered during the design process. However, the wind speed acceleration ratio coefficient for the design wind speed should not be simply selected according to the mountain slope in accordance with the specifications. To comprehensively consider the influence of wind direction and micro-topography on the wind speed acceleration ratio, with the help of CFD simulation analysis, the values of the wind speed acceleration ratio at heights from 10m to 120m at a certain tower location under 24 wind direction angles have been obtained. Combining with the line routing information, the variation laws of the wind loads on the tower body, conductors and ground wires before and after considering the influence of the wind speed acceleration ratio have been calculated and compared. Through analysis, some relevant suggestions regarding the wind resistance design of conductors and ground wires and accident analysis for transmission lines in micro-topography areas have been formed for reference.

穿越微地形地区的输电线路，在设计时应当考虑风速加速效应的影响，但不应当简单的依据山体坡度按照规范规定选用设计风速的风速加速比系数。为综合考虑风向和微地形对风速加速比的影响，借助CFD仿真分析，获取了24个风向角下，某一塔位处的10m至120m高度处的风速加速比取值。结合线路走向信息，对比计算了考虑风速加速比影响前后，塔身、导地线风荷载的变化规律。通过分析，形成了一些有关微地形地区输电线路导地线抗风设计及事故分析的相关建议供参考借鉴。