Classification according to location and function
- National high-ways [N.H]
- State high –ways[S.H]
- Major district roads[M.D.R]
- Other distract roads
- Village roads [V.R]
National high – ways
They run through the length and breadth of the country. They connect all national capitals with state capitals, major cities, towns, border areas. These are considered as arteries of the communication system in the country. They are more important from the strategic point of view. They also connect neighbouring countries. They should have at least two traffic lanes and good surface finishing and excellent strength to carry heavy traffic. The construction and maintenance of these roads are usually carried by the central government. All the national high ways are assigned numbers for example highways connecting, Chennai-Belgium-Pune-Mumbai it’s called N.H-4: Mumbai-Ahmadabad-Jaipur-Delhi is called N.H -; Madurai- Rameshwaram is called 49and so on.
State high – ways
These are the main roads running with thin the states. They connect the important towns and cities of the state with national high ways and high ways of neighbouring states. They generally have one lane but two bituminous or concrete. Surfacing. They are considered as the main arteries of the communication system of the state. The construction and maintenance are usually carried by the state government by taking grants from central government.
Major district roads
These roads connect all the districts, all production area and market with the state high way or national highway or railways. They also further connect the taluka places within the district. They have a single metallic lane of traffic.
Other district roads
These are also called as minor district roads. They possess important because they provide a direct link to the villages and serve a large rural population as they are, should be motorable throughout the year. They should have good metallic surface and proper drainage. They establish connections with major district roads and state high ways. The construction and maintenance are carried out by the district authorities or Zillah Parishad.
These are for the village use. These connect the village with each other and also town nearby. These are generally stabilized earth roads but the metal surface is preferable to serve a more useful purpose. The construction and maintained are carried by the local district boards.
Classification based on materials of construction
- Natural earth roads
- Gravel roads
- Water bound macadam roads
- Bituminous or tar roads
- Cement concrete roads
- Soil stabilized road
Natural earth roads
It is the cheapest type of road it is provided the traffic is rare. The pavement of this road is made of the oil available at the site. The soil is mixed with optimum moisture content, spread and rolled in layers of 10cm. each.
These are called as unmetalled roads and are actually intermediate between earthen and metalled roads. The roadways or pavement of these roads is made by compacting a mixture of gravel and earth the constructed with or without a trench. Since there is better confinement for the gravel, the trench type is preferred. These are superior to earth roads.
Water bound macadam road
The road is named after & engineer john macadam. It is superior to earth and gravel roads. The word macadam now a day is termed as a crushed stone used in the metals. As the name suggests, in the construction of water bound macadam roads crushed stones are kept bound by the action of rolling and voids filled with screening and binding materials with the help of water. The binding action is achieved by using stone dust as filler in the presence of water. To prevent the disintegration of W.B.M roads they are usually protected with any suitable surfacing like bituminous surfacing. WBM roads are very common as a base course for bituminous or concrete pavements.
Bituminous or tar roads
These are constructed with a binder such as bitumen. The top of these bituminous roads appears black so these roads are also known as blacktop roads. These are very popularly used all over the world. The pavement is constructor with varying aggregate sizes, compositions and different types of bituminous binders. They provide a smooth riding surface. They are free from dust nuisance. The roads also called as flexible pavement roads.
Cement concrete roads
These are constructed with cement concrete a mixture of cement fine and coarse aggregates. The thickness depends on the density of traffic. These are more costly than other types of roads but they are found to be cheaper in the long run because of their long span of life, low maintained and can be laid on poor types of such- grade.they have excellent riding surface and pleasing hence cement concrete roads are called as rigid roads since they do not allow any flexibility. Reinforcement is done at times provided to construct a reinforced concrete pavement.
Soil stabilized the road
In this case, the stabilized soil is used for these roads. The term soil stabilization means the improvement of the stability or bearing power of the soil by the use controlled compaction, proportioning and soil by use of controlled compaction, proportioning and addition of suitable admixture of stabilizers such as lime, fly, ash, cement and bituminous materials and from this point of view, it properties so that the selection of stabilizers is proper and also economical.
Classification according to the area of the traverse
- Rural roads
- Urban roads
- Rural roads
These are village roads
Urban roads or streets
- Express highway
- Arterial roads
- Secondary or sub-arterial roads
- Collector roads
- Local roads
- Other roads
- By pan roads ring roads
- Express highways
A new category-express highway is suggested in the third road development plan. These are meant to function as a divided arterial highway for the movement of moving motor traffic under a free-flow condition in big metropolitan cities like Mumbai, Kolkata, Delhi, and Chennai. They have the highest design speed. They cannot major centres for residential area industrial or commercial concentration and the central business district.
Two or three such express highway is necessary to be provided around big cities of modern days to fare the tremendous growth of traffic. As per the restrictions, the speed of the vehicles shows never is less than specified minimum limit while travelling on the express highways. They are, therefore, restricted only to goods and pedestrian traffic are not permitted on their express highways. Way controlled access, grade separators at intersections and fencing.
Express high ways are destined with easy gradients and smooth curves so as carry traffic speedily and safely. There are comparable next to railways in cost and capacity of traffic.