How does the choice of aggregate size affect asphalt layer thickness?

The relationship between aggregate size and asphalt layer thickness is significant because larger aggregates can create a more stable and robust structure within the asphalt mix. When larger aggregates are used, they can interlock more effectively, reducing the amount of binder required to achieve a cohesive layer. This interlocking ability allows for the possibility of thinner asphalt layers while still maintaining structural integrity and performance.

Larger aggregates can also enhance the performance characteristics of the asphalt, such as improved resistance to deformation and better load distribution, which further supports the use of thinner layers. By optimizing the use of larger aggregates, it is possible to reduce the thickness of the asphalt layer without sacrificing quality or durability.

Smaller aggregates, while they have their own advantages, typically require thicker layers to ensure that the binder adequately coats and holds them together, which is not as necessary with larger aggregates. Thus, the correct answer reflects a fundamental aspect of asphalt mixture design and its impact on layer thickness.