Analytical Model to Predict Dynamic Responses of Railway Subgrade due to High-Speed Trains Considering Wheel–Track Interaction

Abstract

In this paper, a full vehicle–track–ground coupling model is presented to evaluate the dynamic response of the subgrade due to high-speed trains. The vehicle was modeled as a multibody. The track was considered as an Euler beam. The ground soil was regarded as two elastic layers and a poroelastic half-space, taking into account a complete subgrade/subsoil system. The wheel–track interaction was considered by using the linear Hertzian contact theorem. The stiffness matrix method and the Fourier transform were introduced to deal with formulations of the coupling model in a transformed domain, and the time-domain solutions were derived by using the fast Fourier transform algorithm. The wheel–track contact forces and the dynamic responses of the subgrade were studied, and the effects of the rail irregularity and the properties of the subgrade bed were then investigated. It was concluded that the dynamic responses of the subgrade are significant compared with responses induced by the axle load and are influenced greatly by rail irregularity and parameters of the subgrade bed.