Research On Wind Field Characteristics Of Typhoon During Landfall

Typhoon is a frequent natural disaster in China's coastal,it has aroused widespread concern in domestic and foreign scholars which will cause great damage and endanger people's lives and property.Field measurement of Wind characteristics is one of the basic research topics in bridge wind engineering.The wind characteristics results based on field measurement can provide evidence for the bridgr wind-resistent design and wind tunnel simulation technology of natural wind.So,research on characteristics of wind field is of great significance.In this paper,as the characteristics of typhoon disater in China's coastal have an effect on the building and bridge structure,according to the observation data of the typhoon characteristics,we studied the wind field characteristics of the distal typhoon during landfall.The research works are mainly concerned with the following aspects:Firstly,the observation instrument of the wind characteristics,observation location and typhoon during landfall are introduced.Secondly,based on the Hilbert-huang transform theory,the non-stationary property of Typhoon Bolaven during landfall with the observation data on Xihoumen bridge is analysized.Under the condition of different time-distance,the non-stationary property of typhoon is also analysized.the non-stationary property of normal wind and typhoon is compared.Based on Emprical Mode Decomposition(EMD),the extracted time-varying mean wind is achieved and analysized.The influence of the non-stationary property on time-varying mean wind is discussed.Thirdly,the time-varying characters of wind spectrum of the distal typhoon based on observed data is analysized.The wind spectrum of typhoon i during landfall is compared.Finally,based on wind characteristics of field measurement and threecomponents of aerodynamic force,the buffeting response of Xihoumen Bridge is analysized by Pseudo Excitation Method.Characteristics of the buffeting response of typhoon during landfall is compared.