2006-10-02 01:07:02 · 14 answers · asked by hellraiza15 3 in Travel ➔ United Kingdom ➔ London
The Ballast is for drainage. Not only does it allow water to drain away from the track and to the sides but it also holds the track above the surface. On railways like the London Underground ballast is not used on track sections below ground (it doesn't rain).
Track is made of the following parts. A flat raised bed, the ballast sits on this, on the ballast are sleepers, the chairs are screwed into the sleepers, the rails sit in the chairs and are locked into place by wooden or metal keys.
Ballast=the large stones you see under the rails
Sleepers=wooden or concrete oblongs placed across the ballast to distribute the weight of trains. Wooden for outside as it shrinks and expands with the sunlight without cracking. Concrete for covered areas underground.
Chairs=metal holders
Keys=wedge shaped wood or metal.
2006-10-02 01:24:14 · answer #1 · answered by Willi 2 · 0⤊ 0⤋
The stone is made of Lime, therefore they they are absorbant to the waters and help the tracks not to get flooded. They also help the track stay in place, and take the pressure of the train resulting in less damage. If the stones were not there the tracks would buckle alot easier as they would have no support.
2006-10-02 08:12:44 · answer #2 · answered by Xapns 1 · 1⤊ 1⤋
Drainage and stability.
If there were no stones, then when it rained, the tracks would move, which is not a good idea if you in a train travelling over that piece of track at 90mph
2006-10-02 17:08:39 · answer #3 · answered by Anonymous · 0⤊ 0⤋
The stone is called Ballast. A few reasons It keeps the ties from sinking in mud when it rains, locks the ties from moving in the ballast so the track dosen't shift.
2006-10-02 11:22:34 · answer #4 · answered by SAM M 4 · 0⤊ 0⤋
It acts like a giant litter tray for the large cats that roam the tracks at night. The use the sleepers as scratching posts too!
2006-10-02 08:15:26 · answer #5 · answered by Anonymous · 0⤊ 1⤋
those stones are the roadbase to support the tracks.the weight of the train would sink the track into the ground without them.
2006-10-02 08:25:10 · answer #6 · answered by frank m 5 · 0⤊ 0⤋
They are a flexible bed to seat the track ties in (much like a beanbag). They also make it easy to replace ties and rails without having to dig them all up.
2006-10-02 08:09:55 · answer #7 · answered by Anonymous · 0⤊ 1⤋
To spread the load onto the ground.
2006-10-02 08:17:50 · answer #8 · answered by Djenawi 1 · 0⤊ 0⤋
To keep sparks from setting a fire and they also act like a foundation for the tracks.
2006-10-02 08:11:32 · answer #9 · answered by Tinkerbelle 6 · 0⤊ 2⤋
Drainage.
2006-10-02 08:08:34 · answer #10 · answered by nert 4 · 0⤊ 1⤋