Sand is another good material for railway ballast. It is one of the cheapest and most readily available materials for ballast. The sand ballast is not used for important line.
This is not preferred for main and branch line. It is only used for packing pot sleepers and also used in case of unimportant rail track.
Following are the advantages of sand ballast
1. It has good properties to drain off rainwater immediately.
2. This material produces a silent track and has been found very good for packing cast-iron pot sleepers.
3. It is very cheap, so it is very helpful for low-cost rail track.
4. It is available in everywhere.
Following are the disadvantages of sand ballast:
1. The sand ballast requires frequent renewal as sand can be easily blown off by winds or washed away by rainwater.
2. It has no stability and gets disturbed easily by vibration, hence, the maintenance of track becomes very difficult.
3. Sand ballast causes wear of rail, seats and keys.