Safe, dependable roadways are vital for all of us as we travel daily to work, school or for a diverse family life. Carmeuse’s Hydrated lime helps asphalt manufacturers to produce high quality asphalt for road surfaces that provide many reliable benefits.
Hydrated Lime for Increasing Asphalt Durability
The benefits in asphalt include:
- Excellent anti-stripping agent - hydrated lime is a proven reagent to prevent stripping, the separation of the asphalt binder from the aggregate due to moisture. For example, one study found asphalt mixtures containing lime to yield tensile strengths up to 8 times higher than similar mixtures without lime. Studies have also shown that lime outperforms other anti-stripping agents such as liquid amines.
- Reduced rutting - Hydrated lime stiffens the bituminous cement (binder), leading to less rutting from heavy wheel loads. For example, for one source of granite, the number of load repetitions to cause a rut depth of 7.5 mm increased from 1,500 loadings for the asphalt test specimen without lime to 7,800 for the specimen containing 1% hydrated lime.
- Improved fatigue properties- Hydrated lime improves the fatigue properties of asphalt pavement. This leads to longer pavement life and lower life cycle pavement cost.
- Retards rate of aging – Asphalt aging is the loss of ductility as it becomes brittle, leading to cracking. Hydrated lime helps the asphalt binder resist the aging effect of oxidative hardening, increasing the pavement's resistance to fatigue cracking caused by repeated wheel loads.
These multi-functional benefits substantially improve asphalt pavement life lowering life cycle costs and helping to create pavement systems that will perform to the highest expectations for many years.