Stress distribution in reinforced railway structures

Abstract

This paper evaluates the performance of a geosynthetic reinforced soil retaining wall (GRS-RW) system as an alternative to a conventional railway embankment. The aim is to investigate the behaviour of the GRS-RW system in terms of displacements and stress levels at different locations in the track and substructure. Full-scale laboratory experimental testing is carried out on a GRS-RW structure, supporting sections of ballasted and slab track, under moving loads at 360 km/h. The tracks are supported by a low-level fully confined conventional embankment and a GRS-RW system, which are constructed to high-speed standards. Displacement transducers and earth pressure cells are placed at different locations to record the displacements of the track and the stress levels in the substructure. The test results show that the pressure levels on the GRS-RW wall are negligibly small for the particular test setup, proving the GRS structure under the action of compaction reached its active state. This means that the reinforced soil was self-supporting under its self-weight and train loads, meaning there was minimal pressure on the walls. Therefore, GRS-RW systems are better alternatives to traditional earth embankments due to enhanced soil stabilisation and less land take.