Performance Improvement of Ballasted Railway Tracks Using Geocells: Present State of the Art

Abstract

The dramatic increase in the axle load and speed of the rolling stock over the recent years has posed several challenges in terms of maintaining the stability and performance of the railway tracks. Consequently, the rail track engineers are exploring suitable measures to improve the performance of the tracks. The geocells can offer a cost-effective and technically viable alternative for enhancing the track performance. Although the performance of geocells in numerous geotechnical applications such as reinforced retaining walls, slopes, embankments , pavements, etc. is well proven, their application to the railway tracks is still in the nascent stage. The present chapter examines the potential benefits of using geocells in the railway tracks. The results of the numerous experimental, numerical and field studies are critically reviewed. The influence of geocell reinforcement on the parameters (or material properties) essential for the track stability have been discussed. The past studies indicate that the geocells can be effectively used to improve the performance of the railway tracks. The geocells provide confinement which increases the strength and stiffness of the infill materials. Moreover, the geocell reinforcement significantly reduces the irrecovera-ble deformations of the track granular media, both vertically and laterally. However , the effectiveness of their use is influenced by several parameters such as the properties of the geocell, infill, subgrade and the location of the geocell reinforced layer. This chapter elucidate the role of these influencing parameters in the track stability. Furthermore, the satisfactory performance of geocells in the field substantiates their enormous applications in the railway tracks.