Vibration Analysis of High-Speed Railway Slab Track on Soil Subgrade with Geometric Irregularities

In order to analyze vibration of high-speed railway slab track on soil subgrade with geometric irregularities, receptances of the slab track at the wheel—rail contact points are derived, an analytical model for the moving vehicle-track vertical coupling vibration is established by considering the moving axle loads and track irregularities. In the model, the moving vehicle is modeled as a multiple rigid body system connected with spring and damper, the slab track structure is simulated by the continuous elastic three layers beam, and the wheel-rail contact is linear Hertzian contact. Vibration of the slab track on soil subgrade caused by a CRH2 high-speed train is analyzed in the numerical example. Dynamic wheel-rail forces due to the vertical track irregularities and maximal vibration acceleration of each component of the slab track structure are produced. Influences of train speed, track irregularities, and stiffness of subgrade on vibration of the slab track are investigated. The computations show that vibration responses of the slab track structure enlarge with the increases of train speed and track irregularities; stiffness of the subgrade has a great effect on vibration of the slabs and concrete base, and has little influence on vibration of the rails.