大跨越输电塔线体系风振响应及风振系数分析

Analysis of wind-induced response and vibration coefficient of long-span transmission line tower

输电塔是高柔度的风敏感结构,大跨越输电塔线体系由于塔线耦合作用,动力特性和风振响应变得复杂。以智力CHACAO大跨越工程为例,在Ansys中建立塔线体系有限元模型,从结构的动力特性和风振响应几个方面对单塔及塔线体系进行风振分析;根据时程分析结果对风振系数进行计算并和规范结果对比,发现按照建筑荷载规范结果不准确也不安全,架空输电线路荷载规范由于考虑了横担处的质量突变等因素,总体来说更符合实际也更偏于安全。

Transmission towers are wind-sensitive structures with high flexibility.The dynamic characteristics and wind-vibration response of the long-span transmission tower-line system are complicated due to the tower-line coupling.In this paper,a finite element model of the tower-line system is established in Ansys15.0 based on an example of long-span project abroad.The dynamic characteristics and wind-vibration response of the structure are analysed.The wind-vibration coefficient is calculated according to the time history analysis results.After calculations and discussions,it was found that the results according to the“load code for the design of building structures”were not accurate and not safe,according to the“Load code for the design of overhead transmission line”,the results were more realistic and safe because many factors such as the sudden increase in mass at the cross arms was considered.