When is a leveling course considered appropriate in asphalt paving?

A leveling course is appropriate in asphalt paving primarily when the pavement cross section has deformed. This situation often arises when pavement has settled, warped, or developed ruts due to traffic loading, environmental factors, or inadequate construction practices. The leveling course is used to restore the surface shape, provide a smooth driving surface, and ensure proper drainage.

This corrective measure allows for the elimination of imperfections, thereby enhancing the overall quality and performance of the roadway. Properly applied, a leveling course not only aids in conforming to design specifications but also extends the lifespan of the pavement by preventing future issues related to water infiltration and uneven wear.

While there may be circumstances where thickness or material considerations could result in other treatments or adjustments, the primary function of a leveling course is specifically to address issues related to deformation in the existing pavement structure.