A graded road is often the first standard road infrastructure that is developed in areas of sandy or rocky countries. Initially either a bulldozer (for rocky areas) or plough (sandy areas) is deployed to drive a road bed surface along the available route. This route may be significantly influenced by the terrain in hilly areas and is often single track.
In a sandy environment the plough will create a windrow or pile of material at each side of the road. This windrow delineates the road from desert. After substantial use or after heavy rain the surface may become rutted or eroded and it is a frequent necessity for a plough to re-grade the surface.
Graded roads can allow vehicle speeds in excess of 80 kilometres per hour (50 mph) but there are often many obstacles that make this unsafe. In dry areas a common problem with graded roads is the creation of a dust cloud by the vehicle in front or from the opposite direction.
|
|||||||||||||||||||||||||||||||||