A study of applying para rubber sheets in railway track by using ballast box test

Abstract

Recently, attempts to reduce ballast degradation have been a major topic for many railways and researchers. Nowadays, a successfully proven alternative is applied elastic under-sleeper pads in between sleeper and ballast particles, and also as the ballast mat placed under the ballast layer. The using of synthetic material as the elastic element is able to decrease the deterioration of ballast and vibrations. Para rubber is a natural elastic material and it is abundant in South East Asia countries. Therefore, this study is aimed to investigate using para rubber as an alternative element of reducing ballast breakage in ballasted track. Experiments were conducted to study ballast behaviors namely the particle breakage, deformation, and modulus of box reaction under similar loading conditions. In this study, cyclic loads from the train at axle loads of 20 tons were simulated on the rigid foundation condition using ballast box to investigate the use of para rubber as an under sleeper pad and ballast mat. Besides, before and after the tested ballast with the elastic element, the application of image processing was used to measure the dimensions of ballast particles to measure the size of particles. Results reveal that the under-sleeper pad made of para rubber can reduce the amount of ballast breakage by 80% of pure ballast case. In addition, the trend of settlement and modulus of box reaction are closed to the ballast reference the most. So In conclusion, this study indicates that the potential of using para-rubber under sleeper pads shall be considered in railway track.