摘要
小根开塔(窄基塔)是输电线路一种新塔型,属于风敏感结构,风与结构的相互作用十分复杂,风荷载常常是设计的主要控制荷载。本文以某一220 kV同塔双回路直线窄基塔为工程背景,建立了详细的有限元计算模型,获得了结构的自振动力特性。在考虑节点风荷载空间相关性的基础上,利用Kaimal谱对结构的风荷载进行了准确的数值模拟。结合动力时程积分法,计算得到了结构的风致振动响应时程。研究了结构位移平均值、位移均方根值和加速度均方根值的分布特点,同时分析了结构各层的荷载风振系数和位移风振系数,并与我国规范进行了对比。通过研究,揭示了窄基塔的风致振动特性,结果可作为窄基塔结构抗风设计的参考。
Small root span tower（narrow base transmission tower） is a new tower type of the transmission line.With the complex interaction between wind and structure,narrow base transmission tower belongs to wind-sensitive structures and the wind load becomes the main problem of the structure design.Based on the engineering background of a double-circuit 220kV narrow base transmission tower,a precise finite element model was established and the vibration characteristics of structure have been obtained.The time history of fluctuating wind load was accurately simulated by considering the spatial correlation of Kaimal wind spectrum.Combination of dynamic time-integration method,the wind-induced vibration responses of the tower were obtained in the time domain.The characteristics of Mean displacement、Rms displacement and Rms acceleration at different layer of transmission tower have been analyzed in a detailed.Meanwhile,the wind-induced vibration coefficient at different layer of transmission tower were also studied and compared,respectively.Through research,some characteristics of wind-induced vibration of narrow base transmission tower were revealed and the procedure and the results presented in this paper can be used as reference for the design of narrow base transmission tower.
出处
《科技通报》
北大核心
2013年第1期86-92,共7页
Bulletin of Science and Technology
关键词
窄基塔
有限元模型
风荷载模拟
时程分析
风致响应
风振系数
narrow base transmission tower
finite element model
wind load simulation
time domain analysis
wind-induced dynamic response
wind-induced vibration coefficient
