Cutback Bitumen
Cutback bitumen is a type of bitumen that is diluted with a solvent to reduce its viscosity, making it easier to handle and apply at lower temperatures. The solvent, which can be either a petroleum distillate or a volatile organic compound, evaporates after application, allowing the bitumen to cure and harden. Cutback bitumen is commonly used in road construction, maintenance, and waterproofing applications due to its enhanced workability and adhesion properties.
There are three main types of cutback bitumen, classified based on the solvent used and the curing time:
- Rapid-Curing (RC): Uses a highly volatile solvent, such as gasoline or naphtha, and cures quickly.
- Medium-Curing (MC): Uses a less volatile solvent, such as kerosene, and has a moderate curing time.
- Slow-Curing (SC): Uses a low-volatility solvent, such as diesel or fuel oil, and cures slowly.
Cutback bitumen offers advantages such as improved penetration, better coating of aggregates, and suitability for cold weather applications. However, environmental concerns related to solvent emissions have led to increased use of alternative materials like emulsified bitumen in many regions.
