Raveling and AgingRaveling and aging are pavement surface deterioration that occurs when aggregateparticles are dislodged (raveling) or oxidation causes loss of the asphalt binder(aging). An ACP loses its smooth surface and begins to appear very open andrough.The severity is rated by the degree of aggregate and binder loss. Rate the overallseverity within the segment as the most predominate observed level.This distress is measured or observed differently depending on whether the roadsurface is BST or ACP.Care should be exercised when rating chip sealedpavements, as they tend to look raveled because of the inherent nature of the chipseal surface. However, raveling in chip sealed pavements (loss of aggregate)actually results in a condition of excess asphalt, and should be rated as flushing(see next distress, Flushing/Bleeding