Railway ballast material selection and evaluation: A review
Ballast is generally defined as a volume of graded crushed rocks, however many other materials have been used or developed to serve as ballast [1].It is typically laid in a compacted layer, generally 250–350 mm thick, as shown in Fig. 1.It has the following functions [1], [2], [3]:. Resistance to the sleepers against vertical, longitudinal and lateral …