Simulation And Analysis Of Rail Corrugation On High Speed Railway Based On Vehicle Dynamic Response

The rapid development of high-speed rail technology in recent years has made the development of China's high-speed railway into a gold period.The operation mileage has been steadily increasing and the speed of operation has been improved again,which has reached 350km/h and is in the front of world.The raise of operating speed requires better vehicle and infrastructure qualities.The better quality of vehicles and infrastructure can ensure a smooth and safe operation of the vehicles.The initial laying of infrastructure requires a lot of design and research work to facilitate the subsequent inspection and maintenance.Since rail traffic came out,there are various kinds of rail diseases on rail.A typical rail wear is called rail corrugation.This disease exists in all kinds of track structures in the world.No matter the speed,no matter the freight or passenger railway,there are different degrees of corrugation.Corrugation has a significant influence on the vehicles running quality.The vehicle has obvious periodic vibration passing through the corrugation,which greatly weaken the ride comfort.The impact of the shock vibration caused by corrugation will be dangerous for operation.In this paper,vibration accelerations of the axle box were actually detected through high speed comprehensive inspection train,and after processing the inspection data,the field measurement was carried out with local maintenance of way branch.It was determined that there was a corrugation with 0.02 mm depth and cosine shape at a certain high speed line.The rail straightness measurement instrument was used to detect the vertical irregularity data on the rail surface.The parameters of rail,fastening and track plate are obtained by field measurement in the solution path,and the vertical irregularities is measured by the rail profile measuring instrument.Furthermore,a 3D wheel/rail transient contact finite element model is established based on ABAQUS/Explicit,which uses the ‘surface to surface' to simulate the wheel/rail contact and use the penalty function to set friction coefficient.Wheel/rail contact force and axle box vibration acceleration is calculated by this model.Then,find out the relationship between key parameters and vehicle dynamic response through modifying the key parameters.Taking the speed of 300km/h as an example,with the axle load of 14 t,the wheel/rail contact force changes from the stable 75 kN to 95 kN when the wheel passes through the rail corrugation,and there is a periodic variation law.Due to the overlap area between rail corrugation and fastening,the wheel/rail force in this section is more complex.At the same time,from the frequency domain analysis of the axle box vibration acceleration,it is obvious that the 60 mm wavelength corrugation corresponds to the 1387 Hz.There are three other characteristic frequencies,that are 615 Hz,498Hz and 752 Hz,which the corresponding wavelengths are 135.50 mm,167.34 mm and 158.04 mm.These results are in agreement with the measured data.It is proved that there is symbiosis relationship among different corrugations,and corrugations will change the motion state of the normal rails on the other side.Modal analysis shows that there are vibration modes related to corrugation.In addition,the ‘M' Mises stress distribution on rail surface is related to the wheel tread of S1002 CN.The maximum contact spot stress on normal rail surface is about 610 MPa,while the maximum contact spot stress is about 710 MPa on corrugation surface.The equivalent plastic deformation on both corrugation and normal rail surface sides have a ‘M' type distribution.When single wheelset passes corrugation rail for once,the equivalent plastic strain on corrugation rail surface has a wave change trend,and the value is between 0.003 and 0.006.Over time,it will undoubtedly deteriorate the rail working state,increase the maintenance cost,shorten the transition period and cause unnecessary waste.The results show that the faster the train running speed is,the greater the vibration amplitude of the axle box vibration acceleration is,and at the same time,the stronger the ability of wheelset return to the original operating state while wheelset leave the solution path.Changing the friction coefficient between wheel/rail contact surfaces cause a tiny influence on calculation results under the same conditions.