What is the ideal moisture content for aggregates before mixing with asphalt?

The ideal moisture content for aggregates before mixing with asphalt is typically in the range of 2-3%. This level of moisture content is crucial for several reasons.

First, having the right amount of moisture helps to ensure that the asphalt binder thoroughly coats the aggregate particles, which is essential for achieving optimal adhesion and bonding within the mix. If the aggregates are too dry, they may absorb more binder, leading to a mix that is not adequately lubricated, which can impair the workability and performance of the asphalt.

Second, maintaining moisture within the 2-3% range minimizes the risk of damage or degradation during mixing and compaction. Excess moisture can lead to stripping, where the asphalt binder can separate from the aggregate due to the presence of water, thereby compromising the integrity of the pavement structure.

Moreover, managing the moisture content effectively also impacts the overall performance of the asphalt pavement, influencing durability, resistance to deformation, and longevity. Consequently, the 2-3% range is widely recognized as optimal to achieve a well-balanced mix that will perform well under various traffic and environmental conditions.