What can excessive air voids in asphalt mixtures lead to?

Excessive air voids in asphalt mixtures can significantly compromise the performance and durability of the pavement. When air voids are too high, the effective asphalt binder content becomes insufficient to coat and bind the aggregates properly, leading to several negative outcomes.

Firstly, high air voids can result in a lower resistance to moisture infiltration, which may cause stripping of the asphalt binder from the aggregate. This process can lead to premature deterioration of the pavement, often manifested as cracking, raveling, or pothole formation.

Secondly, increased air voids negatively impact the mechanical properties of the asphalt mix, making it less able to withstand traffic loads and environmental stresses. This also results in reduced load-bearing capacity, contributing to a shorter lifespan and increased maintenance needs for the roadway.

In summary, the presence of excessive air voids in asphalt mixtures ultimately leads to decreased performance and durability, highlighting the necessity for proper mix design and compaction procedures to maintain the integrity and longevity of asphalt pavements.