Numerical Analysis for Ballasted Rail Tracks: Coupled DEM-FEM Approach

This chapter delves into the critical role of ballasted rail tracks in Australian transportation infrastructure and the challenges they face, such as ballast fouling, differential settlement, track deformation, and noise and vibration issues. The authors present a decade of research outcomes on testing and numerical modelling of ballast using the discrete element method (DEM) and coupled DEM-FEM approach. Large-scale laboratory tests were conducted using a triaxial apparatus to simulate cyclic loading conditions, revealing insights into ballast deformation and breakage. Numerical modelling techniques, including DEM and coupled DEM-FEM simulations, were employed to study the micromechanical behaviour of ballast and its interaction with the subgrade. The chapter highlights the effectiveness of these methods in predicting track deformation and stability, with particular focus on the Singleton track case study. The results demonstrate the potential of coupled DEM-FEM analysis in providing valuable insights into track behaviour and enhancing the resilience and longevity of ballasted rail tracks.