The curious reason why stones are placed under train tracks

Have you ever wondered why trains I’m on a bed of rocks? It is a fact that almost all trains, especially older ones, rest on a bed of small stones. And even though it may go unnoticed, there is a reason why they are there and how essential they are.

The best name ballastthese little “stones” are a type of aggregate with grain size varying between 40 and 150 mm. THE Royal Spanish Academy He also defined it as a “layer of gravel or crushed stone, which is placed on the platform of railway tracks to set and hold sleepers thereon, or on the grading of roads to place pavement on top.”

What are ballasts on train tracks for?

Initially the ballast bed was placed under the train tracks prevent them from sinking the train tracks.

And when the first railway tracks were built, sleepers were placed directly on the platform, but they sank on it because the loads exceeded the load capacity of the panel.

For this reason the professionals of the time agreed that there should be a granular effect under the sleepers to distribute the loads on that surface. To create it they formed these famous stones measuring between 3 and 6 centimetres, created by crushing basalts, granites and quartzites.

Nowadays, reactors also perform other functions such as e.g buffer traffic of trains, prevent the growth of vegetation on the platform, like a pier for dampen vibrations of the land, allow the water drainagegive it stability to the slopes, reduce noiseMoreover.

However, with the arrival of high-speed trains, the placement of these stones was reduced. This is because at high speeds the ballast comes off, which can cause damage to critical railway componentssuch as shock mounts or damaged glass.

To travel safely, damage-free slab tracks are now used. Even though they are much more expensive to build than ballast tracks, maintenance costs are lower and they protect the transport and its passengers.