What is the primary role of mineral aggregate in asphalt pavements?

The primary role of mineral aggregate in asphalt pavements is to act as a stone framework to impart strength. In asphalt concrete, aggregates make up a significant portion of the mixture, typically between 80-90% by weight. This solid structure provides stability and load-bearing capacity, which is essential for the durability and performance of the pavement.

Mineral aggregates resist deformation under traffic loads, ensuring that the pavement can withstand the stresses imposed by vehicles. Additionally, the angular shapes and interlocking nature of the aggregates contribute to the overall strength and performance of the asphalt mix, preventing issues such as cracking, rutting, and wear over time.

While waterproofing is important in asphalt pavements, it is primarily achieved through the asphalt binder itself, which encases the aggregates. Enhancing color and reducing weight are not primary functions of the mineral aggregate; these factors may play a role in specific applications or aesthetic choices, but do not define the main purpose of aggregates in asphalt paving. Therefore, the ability of mineral aggregate to create a robust framework is what directly influences the strength and longevity of the pavement.