What is the reason to put stone pieces (metal) under and around the railway lines.?

Answer 1

Track ballast, consisting of gravel, cinders or other aggregate, forms the trackbed upon which railroad ties are laid. It is used to facilitate drainage of water, and to create an even running surface. This also serves to hold the track in place as the trains roll by. Such a track is also used to bring the Space Shuttle to its launching pad.
In the early days of railroads, much material for ballast came from rock found in the local area. In the Midwest, for example, much use was made of granite, while states in the southeast, such as Florida, made use of limestone. One specific type of granite used in the Midwest earned the name "Pink Lady" due to its color; in other areas, the ballast can be a mix of light and dark colors called "Salt and Pepper".

Answer 2

the the finest option terminology for the "chips", as you call them, is ballast, as has been pronounced formerly. The ballast serves quite a few applications. First and maximum major, the ballast facilitates rain to empty by. without washing away, except of coarse you've flooding circumstances. that is even extra major contained in the chillier areas the position ice might want to kind and push the rail out of allignment. Misalligned rail might want to finally reason a derailment consisting of possable damage or lack of existence to the prepare crew individuals and likewise people residing close to the tracks. Secondly the ballast does help soak up effect from trains. yet another purpose for ballast is to save the rail ties in position, which in turn keeps the rail in position. what's extra awesome is the final structure for progression a railroad mattress has not replaced in over 100 years. Even on the prompt, contained in the age of technologies, little has been done to regulate the shape.

Answer 3

to provide a foundation for the ties and rails and to let water drain away to keep the ties from rotting.

Answer 4

I think bung boy is right