There are three types and causes of asphalt cracking.
- Shrinkage: this is usually found in asphalt parking lots and driveways. These are normally interconnected, forming a series of blocks with sharp corners or angles. The causes of this type of cracking are usually lack of traffic, deterioration of the base, and/or extreme temperature changes.
- Reflective: this is usually found in asphalt overlays. This is almost always caused by vertical or horizontal movements of the pavement beneath due to expansion and contraction with temperature and moisture changes.
- Joint: this is a longitudinal separation along the seams of the paving. This type of crack is caused by a weak seam or an improper pinch roll.
There are four main reasons to seal the cracks:
- Prevents water seepage
- Stops base failure
- Extends life of asphalt
- Keeps out foreign matter