Ballast Level and Fouling Inspection

Track ballast plays an important role in the proper functioning, and ultimately safety, of a railroad track. Ballast is used to transmit and distribute the load of the track and rolling equipment to the subgrade, restrain the track laterally, longitudinally and vertically, facilitate drainage of water, maintain proper cross level, surface, and elevation, as well as inhibit the growth of vegetation.

However, due to weather, train loading, and differences in ballast material quality, ballast can degrade in condition and become less effective over time. For example, heavy rains can result in ballast being washed away and leaving railway ties (sleepers) exposed and more likely to skew.

Ballast can also become fouled due to the fracture and abrasion of ballast particles, infiltration from underlying layers, and spillage from containers in transport. Fouling is often exacerbated by dry-wet cycles and fouled ballast can result in poor drainage and ultimately track surface deviation due to increased layer stiffness.

However ballast inspection is often a very subjective process due to the lack of a formal definition for when ballast is considered fouled and the often manual process of inspection.

Pavemetrics’ LRAIL simplifies the task of ballast inspection by using Artificial Intelligence to analyze both 2D and 3D data in order to precisely and objectively measure ballast height and ballast fouling. Ballast height is automatically measured at the end of ties as well as in the crib area and locations with too little or too much (based on user-definitions) can be flagged. Ballast fouling in the gauge side as well as in the field side can also be automatically detected and quantified objectively. Changes with regard to ballast height and fouling level between repeat runs can be automatically detected and reported.

Standard

49 CFR § 213.233 – Track inspections

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