高耸异型烟囱结构风压和风振系数试验研究

本文在模拟的大气边界层中,对某一发电厂高耸异型烟囱的刚性模型进行了测压试验研究,得到了这一结构的平均风压系数、最大和最小风压系数分布,以及该结构的风荷载体型系数;结果表明在烟囱外形明显变化的局部区域,风压绝对值较大,与理论分析一致。同时,对动态测力试验模型进行了高频动态天平测力试验研究,详细介绍了试验及数据处理方法,根据试验结果计算得到了该烟囱在风作用下的动力响应和风振系数;根据试验结果计算所得的风振系数值大于按规范公式估算值。这些结果不仅为结构的风荷载计算提供了依据,也有助于进一步认识该类异性烟囱结构的风荷载和风振特性。

Experimental Investigation for Wind Pressure and Wind Load Factor of Tall and Special-Shaped Chimney

An experimental study of wind pressure distribution on rigid models of a tall special-shaped chimney was carried out in the boundary layer wind tunnel.The wind pressure coefficients of mean,maximum and minimum values as well as body shape coefficients were obtained.The test results indicate that the pressures at the local positions with remarkable change of shape are much larger than at other areas,which match with the theory analysis.At the meantime,the high-frequency-force-balance tests of the model were carried out.In this paper,the methods of the wind tunnel tests and data processing are presented in detail,and the dynamic wind response and dynamic wind load factor of the chimney are calculated based on the experiment results.The wind load factor calculated according to experimental results is lager than that estimated on code formulas.These results can be useful not only for the design of the structure,but also for further investigation of the wind load and wind-induced vibration characteristics of such special-shaped chimney.