Ballast and recycling spent ballast

摘要

Ballast is a high quality superstructure material that has withstood the dynamic loads exerted by rail traffic and the onslaught of the weather for several decades. The technical specifications for ballast include requirements as regards its particle shape, particle size distribution, attrition and impact resistance (external strength), weather resistance (intrinsic strength) and freedom from dust, in the interests of staff and the environment. The critical factors where the life span of ballast is concerned are the internal and external strength of the stone.