Field Measurements Of Wind Field And Wind Load Characteristics On Low-and High-rise Buildings

China is strongly influenced by typhoon in the world, and there is annual6.6tropical cyclones landfalling in China according to the statistics. In southeast Chinacoast, the casualties and huge property damage caused by typhoon is mainly inducedby a large number of destroyed low-rise buildings. Inadequate research of wind fieldsand wind load characteristics of low-rise building is considered the important reasonsfor the destroyed low-rise buildings. With the rapid development of China economy, agreat number of complex shape and novel style high-rise buildings are constantlyemerging. Modern high-rise buildings has manifested more flexible and lightlydamped characteristics due to adopting high strength and lighter-weight materialswith respect to those in the past. As a consequence, the sensitivity of these high-risebuildings to dynamic excitations, such as strong wind, has increasingly increased.And the wind loads caused by strong wind or typhoon have become the main controlload of structure design for these high-rise buildings. However, there are seriousscarcities of typhoon field full-scale measurement, especially wind pressure full-scalemeasurement for high-rise buildings. Therefore, it is necessary to strengthen thedevelopment of low-and high-rise building wind field and wind loads full-scalemeasurements, which will lay a solid foundation for the wind-resistant design of low-and high-rise buildings in southeast China coast.Supported by four projects of National Natural Science Foundation of China, thedissertation carried out the wind field and wind loads full-scale measurements for theexisting low-and high-rise buildings. Firstly, the dissertation described the researchpresent situation and progress of wind field and wind loads of low-and high-risebuilding home and abroad. The atmospheric boundary layer wind characteristicstheory and corresponding statistical analysis method is also briefly presented.Then, based on the authors field observation in Wenzhou and Xiamen coastalareas in recent years, and combined with a large amount of surface boundary layer andhigh attitude measured typhoon field data, this dissertation demonstrated the meanwind speed and wind direction, turbulence intensity, gust factor, turbulence integrallength scale, spectra of wind speed fluctuations and spatial coherence characteristicsof measured surface boundary layer and high attitude typhoon field data at the terrainnear mountain, island slope terrain and coast areas. Especially, the dissertation analyzed the surface boundary layer wind characteristics and its variation rules duringthe whole passages of typhoon, the surface boundary layer wind profile characteristicsin10m for an existing low-rise building at island slope terrain, and the turbulencecharacteristics and its relationship with different time intervals of surface boundarylayer typhoon field. Furthermore, a comparative study of high attitude typhoon fieldcharacteristics before and after the typhoon field being disturbed by high-rise buildingitself, and a comparative study of turbulence characteristics at different time intervalsof surface boundary layer and high altitude typhoon field are conducted. Based on alarge number of meteorological records, the dissertation also investigated theoccurrence rules of tropical cyclones appearing in West Pacific Ocean and itslandfalling in China, and the characteristics of annual maximum wind speed indifferent areas of Wenzhou district.In this dissertation, the full-scale measurements of wind loads on the existinglow-rise building at island slope terrain is carried out for the first time in China, andthe wind loads characteristics (instantaneous wind pressure, mean wind pressure,mean wind pressure coefficient and fluctuating pressure coefficients) and variationrules of existing low-rise building during the passage of typhoon is obtained. Theresults indicated that, due to the effect of surrounding environment and topography,the wind field around the existing low-rise building is greatly disturbed, the windpressure distribution on the walls and roofs are very complicated, and there is arelative large difference between the measured wind loads and the results oftheoretical calculation.Based on the full-scale measurements and wind tunnel test of wind loads onhigh-rise building, the wind loads characteristics (instantaneous wind pressure, meanwind pressure, mean wind pressure coefficient, gust wind pressure coefficient andfluctuating pressure coefficients) and variation rules of high-rise building during thepassage of typhoon is obtained. The results clearly demonstrate that the mean windpressure characteristics and its variation rules with wind direction on high-risebuilding revealed by full-scale measurements are roughly agree with the wind tunneltest, the mean wind pressure coefficient results of field measurement is obvious largerthan that of wind tunnel test in the windward side, but there is a relative smalldifference between the mean wind pressure coefficient of field measurement and thatof wind tunnel test in other sides.The outputs of this dissertation in wind field and wind loads of low-andhigh-rise building are expected to be useful for further understanding in structural wind engineering, it is also expected that the results presented in this study should bevaluable for wind-resistant design of low-and high-rise buildings.