Study On Wind Characteristics Near Ground Of Typhoon Based On Field Measurements

Wind loading is one of the typical dynamic loadings on buildings, and the effect of wind upon buildings are determined by wind characters. The wind characters in the present code of wind resistance design for civil structures are concluded by the observation of monsoon. However, because there exist big differences between the charaters of typhoon and monsoon, the wind resistance design for civil structures relied on the present code is unrational. According to the oberservation data of the wind characters, we studied the wind characters of typhoon near the ground. There are four chapters:In chapter 1, the background, objective, signification, and present research state at home and abroud are presented.In chapter 2, the instrument used for observing the typhoon characters and the actual typhoon process oberservation in this paper are presented here.In chapter 3, the mean wind velocity, directions, elevations, turbulence instensity, turbulence integral scale, wind speed spectrum and some other characters in typhoon process are analyzed; the changing character of elevations in typhoon process are also found; the longitudinal and lateral tubulence intensity of strong wind (the 10 minitutes mean wind speed is larger than 10m/s) in typhoon process are obtained; an improved method using autocorrelation function to calculate turbulence integral scale is presented; the mean value and coefficient of variation of turbulence integral scale in typhoon process are calculated; the oberservation wind spectrum and experimental wind spectrum are compared; and we found that the Von Karman spectrum matches the observation longitudinal fluctuate wind speed well, and the lateral and longitudinal wind speed which are conduced from Von Karman based on the isotropy theory match the observation spectrum well too, which represents that the isotropy turbulence theory is applicable for typhoon wind field.In chapter 4, the corresponding form of Von Karman spectrum and Davenport spectrum are conduced with the uniform format of fluctuate based on Kolmogrove theory, and the corresponding paramaters are also presented; the two kinds of spectrum form are fitted with the three typhoon process datum in the same location; and we found that the Von Karman spectrum and Davenport spectrum match the...