Performance improvement of ballasted railway tracks using geocells: present status and future prospects

The dramatic increase in the axle load and speed of the rolling stock over the recent years has challenged the stability and performance of the railway tracks. Consequently, rail track designers and engineers are exploring suitable measures to improve the performance of the tracks. The geocells can offer a cost-effective and feasible solution for enhancing the performance of the railway tracks. The satisfactory performance of geocells in numerous geotechnical applications such as reinforced retaining walls, slopes, embankments, pavements, etc. have encouraged their use in other areas too. However, their utilization in the railway tracks is still in the nascent stage. Thus, the present chapter examines the potential benefits of using geocells in the railway tracks. The results of the numerous experimental, numerical and field studies have been briefly 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 provides confinement which increases the strength and stiffness of the infill materials. Moreover, the geocell reinforcement significantly decreases the lateral deformation and permanent settlement of the granular materials. However, the amount of improvement significantly depends on the properties of the geocell, infill, subgrade and the location of the geocell reinforced layer.