What does 'open-graded asphalt' refer to?

Open-graded asphalt refers specifically to a type of asphalt mix characterized by a high air void content, which is intentionally designed to improve drainage. This unique structure allows water to drain through the pavement surface, reducing the likelihood of hydroplaning and improving safety during wet conditions. The increased air voids reduce the overall density of the mix, which fosters a porous surface that can effectively manage stormwater runoff.

This type of asphalt is particularly beneficial in applications where water collection on the surface could lead to issues, such as in areas with high rainfall or in regions prone to flooding. The design and composition of open-graded asphalt aim to enhance pavement performance while ensuring that water quickly permeates through, thus contributing to the durability of the pavement structure over time.