“To Patch or Not To Patch, That Is The Question”
Patching is one of the most common methods of repair of isolated areas of intensive cracking, whether the cracking is load associated (alligator) or environmental or construction related. If the cracking has deteriorated to the point that disintegration of the pavement materials around the cracks is occurring, the defective material must be removed and replaced.
Patching can be either partial or full depth. Partial depth repairs usually involve removing the surface layer and replacing it with hot mix asphalt. Full depth repairs involve the removal of the complete pavement down to the sub-grade or to an intermediate sub-base layer that is intact. Typical repair in flexible pavements for cracked areas involves full depth repairs. Partial depth repairs usually are reserved for slippage cracking due to poor bond to the underlying layer or for shoving and corrugations.
Full depth patching is the most common procedure used for the repair of localized alligator cracking and potholes. A patch consisting of hot mix asphalt can be considered a permanent repair and should last for years. Emergency repairs of potholes frequently involve the use of cold-mix materials under severe environmental conditions. This type of repair is considered to be temporary and serves as an expedient measure in order to keep traffic moving until a permanent repair can be made.