What is the primary role of an aggregate in pavement construction?

The primary role of an aggregate in pavement construction is to provide structural support and stability to the pavement system. Aggregates serve as the main load-bearing component within the pavement structure, distributing traffic loads and ensuring the durability and longevity of the pavement. They contribute to the overall strength and performance of the pavement, helping to resist deformation, cracking, and other forms of failure under various load and environmental conditions.

Aesthetics, while important in certain contexts, are not the primary concern for aggregates in pavement, which are typically chosen for their physical properties rather than visual characteristics. Quality control tests are crucial but pertain to ensuring that materials meet specifications rather than being a role of the aggregate itself. Reducing construction costs is a factor that can be influenced by material choices, but it doesn't define the essential function of aggregates in ensuring that pavement can withstand traffic loads effectively and maintain its integrity over time.