ABSTRACT
The purpose of a railway track structure is to provide a stable, safe, and efficient guided platform for the train wheels to run at various speeds with different axle loadings. This chapter describes the types of track structure used in practice, various components of a conventional track structure, different types of loading imposed on a track system during its predicted life cycle, and the load transfer mechanism. Currently, the two types of rail tracks commonly used are conventional ballasted track and slab track. To effectively design the track substructure, it is essential to know the magnitude of sleeper/ballast contact stress and the distribution of stresses with depth through the ballast, subballast, and subgrade layers. Various methods, including simplified mathematical models and semi-empirical and empirical solutions, are used in practice to evaluate the distribution of vertical stress through the ballast layer. Rail track structures are often subjected to the impact loads due to abnormalities in either a wheel or a rail.
