What can excessive air voids in an asphalt mix lead to?

Excessive air voids in an asphalt mix can significantly compromise the material's overall performance. When there are too many air voids, it can lead to a reduction in the density of the asphalt, which is crucial for its strength and durability. The integrity of asphalt pavements is heavily influenced by the degree of compaction achieved during the laying process; when air voids exceed recommended limits, the mixture becomes more susceptible to moisture infiltration and can lead to premature aging and cracking. This degradation ultimately results in a weaker structure that cannot withstand the stresses of traffic and environmental conditions, thereby shortening the lifespan of the pavement.

In contrast, the other options do not accurately reflect the consequences of excessive air voids: improved surface appearance might suggest a well-graded mix, lower production costs might hint at reductions in material quality, and increased flexibility is typically associated with an adequately designed mix—not one with excessive voids.