Abstract:
The resilient behaviour of the geomaterials used in railway tracks, particularly the ballast layer, is
mostly non-linear and depends mainly on the loading stress path. However geomaterials are frequently
considered as linear elastic in structural analyses, assuming that it somewhat reproduces the results of
non-linear models for a given load amplitude. This study focuses on whether this consideration is
adequate to simulate not only the overall track behaviour, but also the response of the ballast layer,
considering different loading conditions. The authors used three-dimensional train-track-soil system
models, validated with experimental data, and the results of linear-elastic models are compared against
non-linear models. Although the linear elastic models required significantly lower computational
effort and can provide accurate estimates of the overall track response, they strongly underestimate the
stress levels inside the ballast layer. This aspect can be an important hindrance to studies using linear-
elastic models to analyse resilient and plastic deformations of the ballast layer in railway tracks.
