RIS ID
59770
Abstract
The ballast layer is intended to provide a free draining base and sufficient bearing capacity to maintain a proper track alignment. Due to the growth in commuter and industrial traffic, the railway industry needs to fulfil the demands for faster, heavier, and longer trains. However, these high traffic loads often result in a large plastic deformations and degradation of ballast, which in turn, leads to a significant loss of track stability and high maintenance costs. The deformation and degradation of ballast are influenced by factors such as the amplitude and frequency of loading, the number of load cycles, track confining pressure, gradation of aggregates, and the angularity and fracture strength of individual particles. The use of geocomposite (biaxial geogrid-nonwoven geotextile) for enhancing the performance of rail tracks was described, with the aim of reducing track settlement, increasing track resiliency, and decreasing ballast degradation. The effects of impact loads on ballast degradation and its mitigation due to the installation of resilient mats (shock mats) beneath rail tracks were studied using large-scale drop hammer equipment. It has been shown that for tracks built on soft formations, prefabricated vertical drains significantly decrease the build-up of excess pore-water pressure during cyclic loading. A preliminary finite element analysis was used to examine the performance of vertical drains, and a Class A prediction was obtained in terms of settlements, excess pore pressures, and lateral displacements under rail tracks.
Publication Details
Indraratna, B., Nimbalkar, S. & Rujikiatkamjorn, C. (2012). Stabilising railway embankments with geosynthetic grids and drains and a class A prediction of track behaviour. International Symposium on Sustainable Geosynthetics and Green Technology for Climate Change (SGCC) (pp. 21-40).