Numerical Investigations on Track-Substructure System Considering the Effect of Different Train Speeds

摘要

Quasi-static and dynamic loads from train-traffic are applied to the entire track system: superstructure, substructure and subsoil. Due to lack of maintenance of the track bed, the dynamic loads on the track system causes an accumulation of excess pore water pressure within the substructure. Furthermore, a pumping effect exerted on the track system, which depends on the axle load and velocity of the vehicle, may cause in mud hole formation, rising of the underlying soil, ballast contamination and the clogging of gravel bed pores. Consequently, the subgrade resistance is reduced and hence the system loading capacity. The main objective is to detect mud holes as early as possible by non-invasive, non-destructive measurements to avoid costly interim or long term treatments. The present publication focuses on the comparison of vertical velocities due to a moving train load in the absence of water, thus eliminating any complexities arising from any variation in the pore pressure. Due to the large velocity of the trains, elastic and plastic deformations might develop in the vicinity of the track-subgrade system. In the current publication, a simplified numerical simulation of one axle of an ICE train traversing along the rail track with various speeds have been simulated.