Cutback Bitumen

Cutback bitumen is a type of bitumen that has been thinned or reduced in viscosity through the addition of volatile diluents such as kerosene, gasoline, or naphtha. The diluents make the bitumen more fluid and easier to handle, transport, and apply.

Uses of Cutback Bitumen

Cutback bitumen is commonly used in road construction and maintenance, as well as in roofing and waterproofing applications. Its low viscosity allows it to penetrate porous surfaces, creating a strong bond between the bitumen and the substrate.

Types of Cutback Bitumen

There are different types of cutback bitumen, classified according to the type of diluent used, as well as the degree of viscosity reduction. The most common types are:

1. Rapid-Curing (RC) Cutback Bitumen - made by adding a low-viscosity diluent such as gasoline or naphtha to the bitumen.

2. Medium-Curing (MC) Cutback Bitumen - made by adding a higher-viscosity diluent such as kerosene to the bitumen.

3. Slow-Curing (SC) Cutback Bitumen - made by adding a high-viscosity diluent such as diesel oil to the bitumen.

Advantages of Cutback Bitumen

1. Easy to handle and transport.

2. Can be applied at lower temperatures than unmodified bitumen.

3. Provides good adhesion to substrates.

4. Can be stored for longer periods of time than emulsions.

Disadvantages of Cutback Bitumen

1. The volatile diluents used can be flammable and pose a fire hazard.

2. The diluents can also release harmful vapors into the environment.

3. The viscosity of cutback bitumen can change over time as the diluent evaporates, affecting its performance.

Conclusion

Cutback bitumen is a useful and widely used material in the construction and maintenance of roads, roofs, and other structures. Its properties can be modified through the use of different types and amounts of diluents, allowing it to be customized for specific applications. However, care must be taken to handle and store it safely, and to consider its environmental impact.

Correct answer is B
because we heat bitumen then it's viscosity will be reduced, sometimes we use liquid binders that is nothing but cutback bitumen.