Vibration Control Method Based On Vehicle-track-bridge System Coupling And Its Application In Railway Steel Truss Bridge

When the train passes through the bridge,the vehicle load is transmitted to the bridge through the track structure,which causes the vibration problem of the bridge structure.The excessive vibration response of the bridge structure will have an impact on the safety of the train passing,the comfort of the passengers and the service life of the bridge structure,and it is also easy to cause the fatigue damage,cracking and other problems of the bridge structure components.With the rapid development of high-speed railway,the train speed is getting higher and higher.Relevant research shows that the dynamic response of the bridge in the middle of the span is proportional to the train speed within a certain range.Therefore,it is significant and necessary to find a way to weaken the excessive dynamic response of the bridge structure caused by the train load.Although TMD/MTMD has been proposed to control the vibration of bridge structure,the influence of track structure on the vibration response of bridge has been weakened in the establishment of vehicle-track-bridge system model.In this paper,based on the existing research,the vehicle-track-bridge-TMD/MTMD system considering the track structure model is established,and the vibration control effect of TMD/MTMD on the bridge structure is studied in depth.The main research contents and achievements are as follows:(1)Introducing the establishment method of theoretical analysis model of vehicle-trackbridge coupling system,summarizing the research history of vibration control of TMD/MTMD system acting on the controlled structure,engineering examples of TMD/MTMD for bridge vibration reduction,and puts forward the main research contents of this paper.(2)Establishing the theoretical analysis system of single Axle vehicle –track-bridge-TMD considering the track structure model.The wheel rail contact is close contact.The differential equation of track and bridge motion is established by mode superposition method.Deriving and solving the theoretical analysis formula of TMD acting on the controlled structure and carry out the preliminary research on the damping effect of TMD acting on the bridge.The research results show that the vibration control effect of TMD on the bridge with damping is weak,and the vehicle speed has a great influence.(3)Establishing the theoretical analysis model of four axle-vehicle-track-bridgeTMD/MTMD system which considering the influence of adjacent wheelsets.The wheel-rail force is analyzed by nonlinear Hertz contact theory,establishing the differential equation of track motion by mode superposition method,the differential equation of bridge motion is established by finite element method,and the coupled motion equation of the whole large-scale system is solved by explicit-implicit mixed integration method.Studying the vibration control effect of TMD/MTMD on bridge structure,and analyzing and comparing the effect of TMD/MTMD on bridge vibration control when the parameters of TMD/MTMD bridge system changing.The results show that when the TMD/MTMD system acts on the bridge structure with damping,the vibration control effect of the MTMD system is better than that of the TMD system and the control effect is significant,compared with the existing research on the vibration control of undamped bridge structure,the optimal frequency of TMD/MTMD system deviates,and the bridge damping has a greater impact on the vibration control effect of TMD/MTMD on the bridge compared with the bridge stiffness.(4)Taking the 96 m simple supported beam bridge of Yinchuan airport Yellow River Bridge as an example,establishing the actual numerical simulation analysis model of the bridge by ANSYS software,and the spatial coupling vibration model of CRH 2 type vehicle,T60 track and TMD/MTMD acting on the bridge structure by UM software.Studing the vibration control effect of TMD / MTMD on bridge structure and the vibration reduction effect of bridge when TMD / MTMD parameters are changing.The research results show that the influence of TMD parameter mass ratio,frequency ratio and damping ratio on the vibration response reduction effect of bridge is consistent,and in the process of its change,there are optimal parameters suitable for bridge damping.The number of sub TMD of MTMD system has a significant impact on the bridge vibration reduction effect,the band width is not the wider the better,there is an optimal value near the control frequency.