SUBSTRUCTURE SIMULATION FOR TRAIN TRACK/GROUND DYNAMICS

摘要

The wave propagation in the structure and ground induced by the train loads are studied by the substructure method to simulate the track and ground interaction, especially with the sleepers effect. The dynamics system is divided into two substructures: the track system supported by the discretely spaced sleepers via the sleeper-pad and the ground system modelled by the infinity viscous-elastic layered soil under an array of sleepers' loads. Two substructures are coupled with the displacement compatibility conditions. The dynamics formulations are solved using the Fourier integral transform. The structure vibration and the ground motion near the rail line are evaluated from the direct numerical calculation. The sleeper's role in the track/ground simulation is proved to be important to study the ground motion when the train load is below the surface wave velocity of ground. Illustrative case studies are presented based on the real track properties and ground profile.