Bitumen has many uses, but its use in road construction and maintenance, either directly or through asphalt, accounts for nearly 90% of total demand. The main types of bitumen for road applications, including paving grades, bitumen reductants and bitumen emulsions.
- Cutback Bitumen
Cutback bitumen is used in the construction and maintenance of bitumen roads in cold climates. The distillates used in the production of reduced bitumen are naphtha, kerosene, gas oil and furnace oil. There are different types of reduced bitumen, such as fast cure (RC), medium cure (MC) and slow cure (SC). RC is recommended for surface dressing and formation. MC is recommended for premixing with a small amount of fine aggregate. SC is used to pre-mix a significant amount of fine aggregate. This is a grade of bitumen classified as penetration grade bitumen. This type of bitumen is temporarily made less viscous by introducing volatile oils. After application, the volatiles evaporate and the bitumen acquires its original viscosity. Penetration grade bitumen is a thermoplastic material. In road construction areas, the material should be liquid when laying, that is, during surface preparation. It is also necessary that the material recovers its original hardness and properties after installation. This is ensured by lowering the bitumen. The fluidity of bitumen is obtained by increasing the temperature. However, reduced bitumen is used when it is necessary to obtain fluidity at low temperatures during surface coating.
- dilution of volatile oil, and
- the volatility of the oil added.
2. Bitumen Emulsion Bitumen emulsions are liquid products in which bitumen is suspended in finely divided form in an aqueous medium and fixed by a suitable substance. In India, cationic type emulsions are usually used. The content of bitumen in the emulsion is about 60% and the rest is water. When the emulsion is applied to the road it decomposes releasing water and the mixture begins to harden. The curing time depends on the grade of bitumen. The viscosity of bituminous emulsions can be measured according to IS: 8887-1995. There are three types of bitumen emulsion available: fast cure (RS), medium cure (MS) and slow cure (SC). Bitumen emulsions are ideal binders for the construction of hilly roads. Locations where it is difficult to heat bitumen or aggregates. Quickfix emulsion is used for surface coating. Medium setting emulsions are suitable for pre-mixing and patch repair work. Slow emulsions are preferred during the rainy season. This type of bitumen forms a two-phase system with two immiscible liquids. One of them is dispersed in the other liquid in the form of microspheres. A bituminous emulsion is formed when discrete bituminous pellets are dispersed in a continuous form of water. It is a type of penetrating grade bitumen that is mixed and used for laying purposes. Cationic or anionic terminated long-chain hydrocarbon emulsions are used to disperse bitumen pellets. This emulsion provides an electrochemical environment. The ionic portion of the chain has an affinity for water and bitumen is attracted to the hydrocarbon portion. Emulsion stability depends on the following factors:
- Types of bitumen emulsifier and its quantity
- Water evaporation rate
- Bitumen quantity
- Bitumen globules size
- Mechanical forces
Emulsions are applied using a nebulizer. This viscosity is the main concern. As the bitumen content increases, the mixture becomes more viscous. This was found to be sensitive above 60% volume. 
- Bituminous Primers
In bituminous primers, the distillate is absorbed by the surface on which it is spread. The absorption therefore depends on the surface porosity. A bitumen primer is useful on stable surfaces and water-bonded macadamia base courses. Bituminous primers are generally prepared at road sites by mixing permeable bitumen with petroleum distillates. Bitumen primer is applied to any surface where bitumen needs to be adhered. Primers provide the key, sealing porous surfaces that bituminous products need to adhere to, and can be applied to most surfaces including concrete, brick, metallic materials, and existing bituminous surfaces. Bitumen Primer is a bitumen-based primer for surface preparation of concrete and wood substrates prior to application of APP and SBS thermoforming bituminous films. Bituminous primers and black bituminous paints made from oxidized bitumen and selected pure solvents. Black bituminous paint is used for fixing bituminous films, cladding pipes and protecting concrete and metal structures. It can also be applied on damp surfaces. It is also suitable for sealing pores in concrete substrates. The product has a fast-curing time, excellent penetration and adhesion to substrates, and a non-sticky surface. 
- Modified Bitumen
Polymer Modified Bitumen (PMB) is a specially engineered and engineered grade of bitumen used to make high traffic sidewalks and residential roofing solutions to withstand extreme weather conditions. PMB is a polymer addition to ordinary bitumen, which is a suitable material for substructures due to its high strength, high cohesion, and resistance to stress, erosion and deformation. Some additives or combinations of additives, called bitumen modifiers, can improve Bitumen binders and bitumen mixtures. Bitumens processed at these rates are known as modified bitumens. Polymer Modified Bitumen (PMB) / Rubber Modified Bitumen (CRMB) should only be used in the wear cycle as required by severe weather changes. Initially, research on polymer-modified bitumens focused on engineering and experimental measurements such as aging point and softening. However, in recent years, numerous techniques have been used to study a range of properties of bitumen, polymer interactions-bitumen morphology, and the effect of polymer addition on polymer-bitumen. Pavements designed and built for extreme weather conditions with heavy traffic require specially engineered bitumen grades. By adding polymers to modify the properties of regular bitumen, whether elastic or rubbery in nature, it makes the mixture more cohesive with much better strength and much higher resistance to criteria such as fatigue. 
The advantages of using modified bitumen are:
- Less susceptible to daily and seasonal changes in temperature
- High resistance to deformation at high paving temperatures
- better anti-aging properties
- Higher strain life of mixtures
- Improved adhesion between aggregate and binder
- Prevention of cracks and reflective cracks