Study On Coupled Vibration Of High-Speed Train And Cable-Stayed Bridge Under Wind And Rain/Ice

High-speed railways are developing rapidly in China.Largespan bridges are used to cross wide rivers for railways,and cable-stayed bridge is one of the long-span bridge types often used.It is difficult for high-speed trains to avoid wind and rain or wind-ice environment during operation,which affects the all-weather safe operation of high-speed trains.This dissertation focuses on the aerodynamic performance and coupled vibration of high-speed train and cable-stayed bridge under the combined action of wind and rain or wind-ice environment,and the following studies are carried out:(1)The synchronous intelligent observation system of wind and rain field in typical coastal areas of high-speed railway is established.The parameters such as wind speed,turbulence degree and fluctuating wind speed power spectrum of near surface wind field in typical coastal areas and the parameters such as rainfall intensity,raindrop diameter and velocity of rainfall are statistically analyzed.The distribution characteristics of raindrop spectrum of typical tropical wind and rain are analyzed,which enriches the characteristic data of wind and rain field applied in engineering field in coastal areas,It also provides a basis for simulating wind driven rain in the laboratory.(2)By building a wind driven rain test system in the laboratory,the aerodynamic characteristics of CRH-2 high-speed train,cable-stayed bridge and train-bridge system under the combined action of wind and rain are systematically studied,and the effects of rainfall intensity,wind deflection angle and wind attack angle on the aerodynamic characteristics of high-speed train,cable-stayed bridge and train-bridge system are summarized.The relevant conclusions enrich the aerodynamic data of high-speed train and train-bridge system under the combined action of wind and rain,It provides basic data for studying the safety and stability of high-speed train running on subgrade and cable-stayed bridge under the action of wind and rain.(3)The coupling vibration analysis method of high-speed train and bridge under the combined action of wind and rain is established.Taking a railway cable-stayed bridge and CRH-2 high-speed train as the research objects,through the joint simulation analysis of multi-body dynamics software SIMPACK and general finite element method software ANSYS,with the bridge dynamic response,the safety,and stability of high-speed train on long-span cable-stayed bridge under the combined action of wind and rain are systematically studied.The effects of rainfall intensity,train speed and wind speed are analyzed.The relevant conclusions can provide reference for the all-weather safe operation and management of high-speed railway in China.(4)Image recognition technology,three-dimensional scanning technology and particle image velocimetry(PIV)technology are introduced into the study of structural icing process and aerodynamic mechanism in low temperature environment.Taking the bridge cable(standard ordinary cable and cable with helical fillets),which is most affected by ice accumulation due to its small section,as an example,the whole process tracking,nondestructive profile measurement,in-situ aerodynamic test and synchronous flow field observation of the dynamic icing process of two typical ice(rime and glaze)on the structural surface are realized in the laboratory.The effects of surface winding helical fillets and pitch on cable icing process and aerodynamic force are discussed.It provides conditions for the vibration analysis of bridge cables under icing conditions,and also provides a reference for the optimal production and manufacture of cables with helical fillets.(5)The wind-vehicle-bridge coupling vibration analysis model under icing environment is established.Based on the comparative analysis of the change of bridge vibration mode and the track irregularity caused by bridge deformation under low temperature environment,the effects of wheel rail friction coefficient,track irregularity caused by low temperature deformation,driving speed and other factors on driving safety,stability and dynamic response of the cable-stayed bridge are systematically studied,It provides a scientific basis for the operation and management of high-speed railway in low temperature environment.148 Figures,24 Tables,244 References...