Vibration analysis of high-speed railway tracks with geometric irregularities

In order to analyze vibration of high-speed railway tracks with geometric irregularities,receptances of the vehicle at the wheelsets and the track at the wheel-rail contact points are derived,an analytical model for moving vehicle-track vertical coupling vibration is established by considering moving axle loads and track irregularities.In the model,moving vehicle is modeled as multiple rigid body system connected with spring and damper,ballasted track structure is simulated by the continuous elastic three layers beam,and wheel-rail contact is linear Hertzian contact.Vibration of the ballasted track structure caused by a TGV high speed locomotive is analyzed in the numerical example.Dynamic wheel-rail forces due to track irregularities and the maximal vibration acceleration of each component of track structure are produced.Influences of train speed,track irregularities,and stiffness of sub-rail foundation including rail pad and fastening,ballast,subgrade on the track structure vibration are investigated.The computations show that vibration responses of track structure enlarge with increases of train speed and track irregularities;stiffness of sub-rail foundation has a great effect on the vibration of sleeper and ballast,and has little influence on rail vibration.