Surface Defects

Raveling

Progressive loss of pavement material from the surface downward caused by: stripping of the bituminous film from the aggregate; asphalt hardening due to aging; poor compaction especially in cold weather construction; or insufficient asphalt content.  Slight to moderate raveling has loss of fines, while severe raveling has loss of coarse aggregate.  Raveling in the wheel paths can be accelerated by traffic.  Repair the dry weathered surface with a seal coat, or a thin overlay if additional strength is required.

 

Slight - Smallest aggregate particles worn away exposing tops of large aggregate.

 

Moderate to Severe - Erosion further exposes large aggregate.

 

Severe - Loss of large aggregates leaves very rough texture (foreground).

Flushing

The presence of excess asphalt on the surface caused by too high asphalt content, or by paving or sealcoating over a flushed surface.  Repair by blotting with sand or by overlaying with properly designed asphalt mix.  Dark patches in photo are where asphalt has worked to surface.

 

Polishing

A smooth slippery surface caused by traffic polishing off sharp edges of aggregates.  Repair with sealcoat or thin bituminous overlay using skid resistant aggregate.