Even the best of construction materials need repair from time to time. One of the advantages of asphalt pavement is the comparative ease of making effective repairs to distressed areas. There are two types of patching in pavement maintenance: Remove and Replace (R&R) and Skin or Surface Patching.
REMOVE & REPLACE
The most common forms of distress are fatigue cracking and structural failures. These distresses may be caused by overloading the pavement with vehicular traffic and or water infiltration to the sub-grade. These cracks are visible in the form of alligator cracking, potholes, sags, ruts, depressions and lateral displacement. With these types of distresses, the best option is to remove and replace patch the failed area. This process consists of saw cutting the area where structural damage has occurred, removing the area and patching it back with hot mixed asphalt.
SKIN OR SURFACE PATCHING
Another common form of pavement distress is raveling. Raveling is caused by water, ultraviolet rays, and or gas/oil spills resulting in the asphalt and aggregate to separate and erode the surface away. Depending on the damage, the best option may be to perform and skin or surface patch. This process consists of applying a thin hot mixed asphalt patch on the surface of existing pavement where it has been deteriorated or weathered. A variation of skin or surface patching is called fabric skin patching. Fabric skin patches are regular skin patches placed over a fabric inner layer between the patch and the original pavement to add longevity to the patch.