Why are there rocks on the railroad tracks

Have you ever wondered why there are rocks lying on railroad tracks?

Stones lying along the tracks play a key role in the operation of railroads.

They are called road ballast and serve several important functions.

First, it holds the sleepers and rails in place, preventing them from shifting under the weight of trains.

Secondly, crushed stone performs a drainage function: it drains water, preventing the soil under the rails from eroding.

And finally, the stones dampen vibrations from trains passing along the tracks.

As a result of its uneven surface, crushed stone softens vibrations, prolonging the service life of the tracks.