The physical condition of railway ballast should be regularly inspected and accordingly, ballast cleaning should be carried out to maintain the safe operation of a track. This paper reviews current methods commonly used for evaluating the degree of ballast fouling, and due to their limitations, a new parameter — ‘‘relative ballast fouling ratio’’— is proposed. Categories of fouling based on the proposed method are derived from the particle gradation curves taken from past literature. Comparisons between these methods demonstrate that the newly proposed relative ballast fouling ratio would best represent the influence of the type and gradation of fouling material.
Available at: http://works.bepress.com/crujikiatkamjorn/59/