超大型冷却塔风荷载时程响应及动力抗风性能分析

ANALYSIS OF WIND PRESSURE TIME-HISTORY RESPONSE AND WIND RESISTING PERFORMANCE FOR SUPER LARGE COOLING TOWER

采用风洞实验测试和人工生成的方法分别获取某电厂220 m高超大型冷却塔达文波特风压时程数据,并基于国内规范和特征值屈曲建立了结构模型,采用有限元计算方法分析了风荷载动力抗风特性,并对结果进行了对比分析。结果表明:人工生成风压时程结构响应大于风洞实验实测风压响应,人工生成风压时程作用下整体位移和所提取单元各层壳应力均有较大幅度的波动,总体应力状态远低于混凝土强度设计值;在动力风荷载作用下,结构变形最大位置位于迎风面塔体喉部,应力最大位置位于迎风面塔体下部;基于特征值屈曲建立的结构模型整体变形大于国内规范建立模型变形值。研究成果可为超大型冷却塔表面风荷载取值和相关技术规范修订提供参考。

Wind tunnel tests and an artificial generation method were used to measure the wind pressure time-history response of a 220 m-high super large cooling tower,and a structural model is established based on the domestic standard and eigenvalue buckling.Finally,the finite element method was used to analyze the wind load dynamic wind resistance characteristics.The analysis results indicate that the response of artificial wind pressure is larger than that of wind tunnel tests.The overall displacement and each layer stress of the extracted unit by the artificial generation method have a large fluctuation.Under the action of dynamic wind loading,the maximum deformation of the structure is located in the throat of the windward tower,and the maximum stress is located in the lower part of the windward tower.The results can provide a reference for the revision of the surface wind load of the super-large cooling tower and relevant technical specifications.