Track ballast modelling by discrete element method

Sa？etak An increase in axle load and travel speed causes faster degradation of track structure and, hence, of the ballast prism. Crushing of stone grains in ballast due to excessive contact forces among these grains causes degradation in the form of filling of voids and, in turn, in poorer drainage, which can cause structural failure. The degradation of ballast prism can significantly be reduced, and total maintenance costs can be cut down considerably, by optimizing frequency of maintenance activities and by proper ballast design and shaping based on numerical and experimental procedures. The possibilities of using the discrete element method for predicting track ballast behaviour are presented in this paper