Track ballast

Trackbed upon which railway ties are laid

Track ballast is the material which forms the trackbed upon which railroad ties are laid. It is packed between, below, and around the ties. It is used to bear the compression load of the railroad ties, rails, and rolling stock; to facilitate drainage; and keep down vegetation that can compromise the integrity of the combined track structure. Ballast also physically holds the track in place as the trains roll over it. Not all types of railway tracks use ballast.

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