Asphalt Pavement Distress Conditions and Recommendations
Wear and Flushing
Traffic wear and snowplowing tend to remove cover aggregate from paved lots. Slight wear is normal, but a significant loss may be due to poor construction practices that are aggravated by traffic volume. Extensive wear and loss of pavement aggregate creates a “flushed” surface where asphalt oil bleeds through the surface. If flushing is severe, tracking and ruts many appear.
Recommendation: New sealcoating surface
Loss of Surface
The top layer of the sealcoat may come loose and peel off. This failure of the bond between layers can be caused by applying seal coat over dirt/debris or an application done in weather that was too cold. Sealcoat is often less than 1/8 of an inch thick and can be susceptible to breakage if not applied properly. Edges are most vulnerable, especially at intersections.
Recommendation: Patch repair Extensive damage may require a new sealcoat or overlay. Before making the decision to reseal, evaluate the following:
- Current traffic
- Future traffic flow and volume
- Asphalt quality
- Drainage issues
Loss of surface from many factors will eventually lead to the loss of base gravel and pot holes. Early surface repair and good maintenance can keep pot holes from forming. However, extensive pot holes could indicate water retention areas, lack of bonding oils and poor base conditions.
Recommendation: Major Improvements in base gravel and drainage are most likely necessary before resealing.
Surface failure patches such as rutting, cracking and loss of surface may indicate that the sealcoating has reached end of service life. Alternatively, the cause may be inadequate base gravel and traffic volume.
Recommendation: Patch repairs with a hot or cold mix asphalt material. Crack sealing is more effective in bonding broken areas where cracks are far apart.
Edges are most susceptible to early cracking from traffic volume as it is not supported by the adjacent sealed surface and may have drainage issues.
Recommendation: Improve drainage and patch
Alligator cracking is a series of interconnecting cracks in an asphalt pavement surface forming a pattern that resembles an alligator’s hide. In its early stages, alligator cracking may be characterized by a single longitudinal crack in the wheel path. The cracks indicate fatigue failure of the surface layer and can be a sign that the base gravel is inadequate for the traffic volume and poor drainage.
Recommendation: Consider base repair and drainage improvement before resealing