Based on the thought of the system engineering theory,the questions about the dynamic characteristics of vehicle-track coupling system on curved track and the vibration response of ballastless track structure of passe...Based on the thought of the system engineering theory,the questions about the dynamic characteristics of vehicle-track coupling system on curved track and the vibration response of ballastless track structure of passenger traffic railway are analyzed and are simulated research.The main searches are as follows:(1) Depending on the theory of vehicle-track coupling dynamic and finite element method,the motion state of each part of the vehicle-track coupling system is analyzed in particular.The dynamic models of vehicle structure,curve ballasted track structure,ballastless track structure are built separately.The rail/wheel contact model adopting FEM to calculate the rolling contact progress is brought forward.LM worn profiled wheel tread is adopted.Each part of the track structure model is built by real size and relation,and is simplified appropriately.The calculation about rail/wheel contact interaction is close to real status.The wheel can roll on the track,or glide relative to track,or separate from track.Thus,the phenomena of the vehicle’ climb on rail and derail are simulated. Through applying the wheel rotate velocity,the forward rolling of the wheel is realized,and then it is true more than giving a vehicle velocity.(2) Adopting ABAQUS software,the vehicle-track coupling system of Passenger Traffic Railway is simulated research.Explicit method and the contact penalty function method are used for calculation.In the contact calculation,constraint enforcement methods is described the pressure-overclosure behavior,contact surface weighting method & tracking approach are used to judged contact state,contact tangent action is described by corresponding sliding formulation.The calculate results show that adopting FEM to calculated rolling contact progress is feasible and the results is more exact.(3) Taking example by the engineering of rail traffic in a city,the dynamic characteristics of the vehicle-track coupling systems of ballasted track and ballastless track are simulated respectively.By contrasting the simulation result with test data,the models of vehicle structure,curve ballasted track structure,ballastless track structure in the thesis can better reflect the dynamic characteristics of vehicle-track coupling systems.Simulation results are close to actual data.(4) The dynamic characteristics of vehicle-track coupling system on curved track of passenger traffic railway are simulated systematically.The relation among the vehicle velocity,the least curve radius and designed elevation of curved track of passenger traffic railway is analyzed,and the simulation working condition of vehicle-track coupling system on curved track of passenger traffic railwayis determined.The dynamic characteristics of the coupling system between 300 km·h-1 motor train unit with diversified power supply and the curve track are analyzed.Vibration response of curve track coupling system is obtained.The safety and riding index of curved track and the relation curve between the vibration response parameters of each part about track structure and the vehicle velocity,the least curve radius and the designed elevation are analyzed.The results show that the building model and the analysis method can be used to search the high frequency response of the coupling system acted by high velocity vehicle.(5) By means of vehicle-track coupling system dynamic characteristics simulation models of ballastless track structure on passenger traffic railway,when 300 km·h-1 motor train unit passes by with the velocity of 200—350 km·h-1,the vibration responses of slab & twin-block ballastless track structure on soil subgrade are simulated.The simulated results show that ballastless track structure has good smoothness,the vibration of each structure’ part is enlarged with the increase of the vehicle velocity,the vibration frequency ranges of track,slab and subgrade are enlarged with the increase of the vehicle velocity,and the ballastless track structure has well the vibration attenuation regularity in view of the vibration transfer curve.The similarities and differences of the dynamic characteristics between slab and twin-block ballastless track structure are compared.The quantized analysis of the elastic difference among ballasted track,slab ballastless track and double ballastless track is carried out.The analysis results show that the elasticity of the ballast track is best,the elasticity of the slab track takes second place,and the twin-block ballastless track is worst.In the calculated condition,the rail vibration above 45 Hz in the ballast track is completely absorbed,and the rail vibration above 60 Hz in the ballastless track is completely absorbed.Under 45 Hz,the rail-top of subgrade transfer function amplitude of the ballast track is smaller than the amplitude of the ballastless track,and the rail-top of subgrade transfer function amplitude of the slab ballastless track is smaller than the amplitude of the twin-block ballastless track except that 20.14 Hz.展开更多
文摘Based on the thought of the system engineering theory,the questions about the dynamic characteristics of vehicle-track coupling system on curved track and the vibration response of ballastless track structure of passenger traffic railway are analyzed and are simulated research.The main searches are as follows:(1) Depending on the theory of vehicle-track coupling dynamic and finite element method,the motion state of each part of the vehicle-track coupling system is analyzed in particular.The dynamic models of vehicle structure,curve ballasted track structure,ballastless track structure are built separately.The rail/wheel contact model adopting FEM to calculate the rolling contact progress is brought forward.LM worn profiled wheel tread is adopted.Each part of the track structure model is built by real size and relation,and is simplified appropriately.The calculation about rail/wheel contact interaction is close to real status.The wheel can roll on the track,or glide relative to track,or separate from track.Thus,the phenomena of the vehicle’ climb on rail and derail are simulated. Through applying the wheel rotate velocity,the forward rolling of the wheel is realized,and then it is true more than giving a vehicle velocity.(2) Adopting ABAQUS software,the vehicle-track coupling system of Passenger Traffic Railway is simulated research.Explicit method and the contact penalty function method are used for calculation.In the contact calculation,constraint enforcement methods is described the pressure-overclosure behavior,contact surface weighting method & tracking approach are used to judged contact state,contact tangent action is described by corresponding sliding formulation.The calculate results show that adopting FEM to calculated rolling contact progress is feasible and the results is more exact.(3) Taking example by the engineering of rail traffic in a city,the dynamic characteristics of the vehicle-track coupling systems of ballasted track and ballastless track are simulated respectively.By contrasting the simulation result with test data,the models of vehicle structure,curve ballasted track structure,ballastless track structure in the thesis can better reflect the dynamic characteristics of vehicle-track coupling systems.Simulation results are close to actual data.(4) The dynamic characteristics of vehicle-track coupling system on curved track of passenger traffic railway are simulated systematically.The relation among the vehicle velocity,the least curve radius and designed elevation of curved track of passenger traffic railway is analyzed,and the simulation working condition of vehicle-track coupling system on curved track of passenger traffic railwayis determined.The dynamic characteristics of the coupling system between 300 km·h-1 motor train unit with diversified power supply and the curve track are analyzed.Vibration response of curve track coupling system is obtained.The safety and riding index of curved track and the relation curve between the vibration response parameters of each part about track structure and the vehicle velocity,the least curve radius and the designed elevation are analyzed.The results show that the building model and the analysis method can be used to search the high frequency response of the coupling system acted by high velocity vehicle.(5) By means of vehicle-track coupling system dynamic characteristics simulation models of ballastless track structure on passenger traffic railway,when 300 km·h-1 motor train unit passes by with the velocity of 200—350 km·h-1,the vibration responses of slab & twin-block ballastless track structure on soil subgrade are simulated.The simulated results show that ballastless track structure has good smoothness,the vibration of each structure’ part is enlarged with the increase of the vehicle velocity,the vibration frequency ranges of track,slab and subgrade are enlarged with the increase of the vehicle velocity,and the ballastless track structure has well the vibration attenuation regularity in view of the vibration transfer curve.The similarities and differences of the dynamic characteristics between slab and twin-block ballastless track structure are compared.The quantized analysis of the elastic difference among ballasted track,slab ballastless track and double ballastless track is carried out.The analysis results show that the elasticity of the ballast track is best,the elasticity of the slab track takes second place,and the twin-block ballastless track is worst.In the calculated condition,the rail vibration above 45 Hz in the ballast track is completely absorbed,and the rail vibration above 60 Hz in the ballastless track is completely absorbed.Under 45 Hz,the rail-top of subgrade transfer function amplitude of the ballast track is smaller than the amplitude of the ballastless track,and the rail-top of subgrade transfer function amplitude of the slab ballastless track is smaller than the amplitude of the twin-block ballastless track except that 20.14 Hz.
