What is Bitumen?

Bitumen is a non-crystalline solid or viscous material derived from partial distillation of crude petroleum, substantially soluble in carbon di-sulphide & trichloro - ethylene. It is asphalt in solid state & mineral tar in semi-fluid state. Bitumen is brown or black in colour possessing water- proofing & adhesive properties.

Composition:

• Carbon- 87%

• Hydrogen- 11%

• Oxygen-2%

Production:

• It is obtained as a last product of fractional distillation of crude petroleum.

• The heaviest material obtained from the Fractional distillation process is further treated and blended to make different grades of paving grade bitumen.

Why is Bitumen used in Road Construction?

The primary use of bitumen is in road construction, where it's used as the glue or binder mixed with aggregate particles to create asphalt concrete. It's used in road construction to bring flexibility to pavements and ensure they strongly bind and hold the construction components together and provide a smooth and levelled surface for the moving vehicles.

Below are the properties of bitumen as they continue to be favoured as the most important material in construction.

• They consist of adhesives which bind together all the components without bringing about any positive or negative changes in their properties.

• Waterproof: Bitumen is insoluble in water and can serve as an effective sealant.

• Strong: Though the coarse aggregates are the main load-bearing component in a pavement, they also play a vital role in distributing the traffic loads to the layers beneath.

• Durable: Bitumen lives up to twenty years if maintained properly throughout the pavement life.

• Versatile: Bitumen is a relatively easy to use the material because of its thermoplastic property. It can be spread easily along the underlying pavement layers as it liquefies when heated making the job easier and hardens in a solid mass when cooled.

• Economical: It is available in cheaper rates almost all over the world.