Road Repair Techniques
Full Depth Reclamation (PCI 0 - 60)
Full Depth Reclamation (FDR) is a pavement rehabilitation process that involves grinding, pulverizing, and mixing the existing pavement material with part of the underlying base gravel to create a uniform base material. The material is then graded and compacted to form the final base layer. In some cases, a stabilizing agent such as calcium chloride or asphalt emulsion are added in a second pass to create a more bound and stronger base. The FDR process provides an opportunity to correct road profile issues and break the crack pattern, while using existing materials to create a stronger uniform base layer.
Mill and Overlay (PCI 45 - 70)
Mill and Overlay (otherwise known as Mill and Fill) is the process of grinding off the top layer of existing asphalt pavement by means of a large milling machine and replacing this layer with a new hot mix asphalt riding surface. Typical depth of milling is between 1 and 2 inches, depending on the condition of the existing riding surface, depth of available curb reveal and depth of existing asphalt pavement. A leveling course may applied prior to the final riding surface to resolve rutting, depressions or other roadway profile issues.
Crack Seal (PCI 70 - 95)
Crack Sealing is used to keep excess water or moisture from penetrating asphalt and to prevent further cracking, base failures and the overall deterioration of roadway. The process uses compressed air and a high-pressure blow pipe to remove dirt, debris, and water from existing cracks. A kettle heats the crack sealing compound, which is then delivered to the pavement surface through a pressure hose line and applicator shoe. The shoe width and sealer overbanding area are two to four inches wide. When traffic requires immediate use of the roadway, a boiler slag aggregate may be broadcast over the crack seal compound to prevent sealer pickup.