The need to develop new means of optimizing the performance and minimizing maintenance requirements of railway ballast has become more pressing. This is due to the growing need for the development of resilient track materials (including ballast) capable of withstanding increasing train speed, load and frequency. In recent times, railway ballast has been reinforced mostly by the use of geogrids placed at strategic depths within the ballast layer. However, experience has shown that the presence of geogrids restricts the type of maintenance activity (tamping) that can be carried out on the reinforced track section. The addition of random fibre reinforcements in ballast has been proposed as an alternative reinforcement technique that can meet the reinforcement requirements of ballast without limiting future maintenance activities. Using novel digital-image based deformation measurement technique for triaxial tests, the deformational evolution of random fibre reinforced scaled ballast was investigated. The mechanism of reinforcement in the reinforced granular material is highlighted and the potential applications in railway ballast discussed.
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