超高层建筑实测风压相干性的小波分析

Wavelet analysis for coherence of full-scale measured wind pressure on a super tall building

在结构的顺风向动力响应计算中,高层建筑上任意两点风压的空间相关性信息是必需的。风压全尺度实测是分析建筑物风压相干性的必要途径,而小波变换为非平稳风压间的相干性分析提供了有力的工具。为了获得超高层建筑风压的相干性信息,针对一超高层建筑进行了强风下的风压现场实测,基于小波变换分别进行了风压间小波相干和考虑伪相干的小波相干分析,对各测点之间风压的相关性与依据经验公式计算的风速相关性进行了比较。比较结果表明,在低频区域,任意两点脉动风速的相干性高于脉动风压的相干性;反之亦然。

For estimation of along-wind structural responses,the information about the spatial correlation of wind pressures between any two points on a super tall building is required.The full-scale measurements of wind-induced pressures are necessary to analyze the coherence of wind pressures on wall faces of a building.It is known that the wavelet transformation provides a powerful tool to analyze the coherence of nonstationary wind pressures.In order to obtain the coherence information between wind-induced pressures,wind field full-scale measurements were accomplished on a super tall building.The coherence between wind pressures,with and without considerations of spurious coherence,respectively,was analyzed by using the wavelet transformation.Likewise,the coherence of wind-induced pressure fluctuations was compared with that of wind velocity fluctuations derived in accordance with an empirical formula.The comparative results demonstrated that in lower frequency domain,the coherence of wind velocity fluctuations is higher than that of wind-induced pressure fluctuations,between any two points on a super tall building;and vice versa.