Degradation of the railway ballast occurs in the classical railway structure after a certain time of use. Several factors influence the life span of the ballast, such as quality of the stone material, quality of subgrade, sleepers, loadings of the structure, etc. In order to determine and predict the behaviour of the ballast, we need to define the load transfer path and interaction of the ballast particles. The numerical simulations are usually carried out in order to determine the characteristics of the loaded structure. Discrete element method (DEM) has several advantages in use for research of the granular material such as railway ballast. Several simplifications of the railway system in the numerical models affect the accuracy of the simulation results in different ways. This review paper of the numerical simulations on ballast behaviour, presents that results of the simulations are in a good agreement with experimental investigation results, therefore the use of numerical models for prediction of railway ballast behaviour is justified.

railway ballast, numerical modelling, discrete element method, analysis