Asphalt pavements are subject to a variety of distresses and failures over time due to various factors such as climate, traffic loading, and construction quality.
- Ravelling: It is the ongoing separation of fine aggregate particles from the surface.
- Rutting: Ruts in asphalt pavements are channelized depressions in the wheel tracks. It results from consolidation or lateral movement of any of the pavement layers or the subgrade under traffic.
- Longitudinal Cracking: Longitudinal Cracking is cracking that is parallel to the centre line of the pavement. These can be a result of pavement fatigue, reflective cracking, and/or poor joint construction.
- Transverse Cracking: Transverse Cracking is single cracks perpendicular to the pavement’s centre line. These cracks can be caused by reflective cracks from an underlying layer, daily temperature cycles, and poor construction due to improper operation of the paver.
- Block Cracking: Block cracks look like large interconnected rectangles (roughly). Block cracking is not load-associated, but generally caused by shrinkage of the asphalt pavement due to the inability of the asphalt binder to expand and contract with temperature cycles.
- Alligator Cracking: Alligator cracking is a load-associated structural failure. The failure can be due to weakness in the surface, base or sub-grade; a surface or base that is too thin; has poor drainage or a combination of all three.
- Pot Holes: Small, bowl-shaped depressions in the pavement surface penetrate all the way through the asphalt layer down to the base course. Potholes are the result of moisture infiltration and are usually the end result of untreated alligator cracking.