以2012年“达维”和“海葵”台风期间苏通大桥SHMS实测风数据为研究对象,采用游程检验法对桥址区实测风速进行了平稳性检验,对比分析了基于平稳和非平稳风速模型计算得到的平均风速风向(时变)、紊流强度、紊流功率谱密度等风特性,并采用基于小波变换(WT)的演变功率谱密度(EPSD)估计方法,进行了实测强风非平稳演变功率谱分析.结果表明,实测风速表现出明显的非平稳特性;由于时变趋势项的引入,非平稳风速模型比传统平稳风速模型能更好地表征实测强风特性;所得演变功率谱密度直观地展示了实测脉动风速能量的时频分布,EPSD均值与傅里叶变换谱吻合良好,验证了EPSD估计的可靠性.研究结果可为今后非平稳风场实测分析及数值模拟提供参考.%Wind data measured by SHMS of Sutong Bridge During typhoon Damrey and Haikui in 2012 are taken as the research object.The stationarity of wind speed at the bridge site is firstly tested utilizing the run test method.Based on the stationary and non-stationary wind speed models,the obtained wind characteristics such as mean wind speed,turbulence intensity,turbulence power spectral density are calculated and compared.Also,the evolutionary power spectral density of the wind speed time history were estimated using the EPSD estimation method based on Wavelet Transform (WT).Results show that the measured wind speeds present strong non-stationary characteristics.The non-stationary wind speed model,which introduces the time varying trend,is more suitable to represent the wind characteristics of measured strong winds than the traditional stationary model.The obtained EPSD can reflect the energy distribution of the measured turbulence wind speed in time-frequency domain.What's more,the averages of EPSD are in good agreement with the traditional Fourier-based PSD,which proves the effectiveness of the method in this article.Results can provide references for field measurement and numerical simulation of non-stationary wind field.
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