As freight trains become longer, heavier and quicker, ballast shows signs of distress and degradation, leading to deterioration of the track substructure. Appropriate stabilization techniques using artificial inclusions such as polymeric geosynthetics and energy-absorbing rubber mats are commonly employed to improve track stability and longevity.This paper presents the current state-of-the-art knowledge of track geomechanics based on advanced laboratory and computational modelling, as well as real-life health monitoring of selected track sections. Full-scale instrumented field monitoring supported by Australian rail organizations has been carried out to obtain measurements of in-situ stresses and deformation of ballast embankments, and thereby evaluate track performance supplemented by computational models.In the past decade, the authors have tested different types of geosynthetics and shock mats both in the laboratory and in the field where these geo-inclusions were placed beneath the ballast layer in tracks constructed on various subgrade conditions. Traffic induced stresses, ballast breakage, transient and permanent deformations of the substructure were routinely monitored using precise instrumentation schemes. These results provide promising approaches that can be incorporated into existing track design routines to cater for future high speed freight trains carrying heavier loads.