Typically, throw and roll pothole patches will likely fail before the pavement is resurfaced or rehabilitated. Alternatively, semi-permanent repairs are time consuming and require more people and added lane closure time. An alternate method is available to quickly, safely and permanently patch potholes that can be employed year-round. Although not currently used in Oregon, a successful pothole repair method used in other states is spray injection. Spray injection is a process where using specialized equipment, aggregate is simultaneously pre-mixed with a heated emulsion and sprayed through a hose and nozzle into the pothole.
Air is blown into the pothole to remove any standing water or loose debris.
The bottom and sides of the pothole are coated with asphalt emulsion A mixture of asphalt emulsion and aggregate is blown into the hole filling it to surface grade. In addition to repairing potholes, spray injection equipment can be used to repair alligator cracking, transverse cracking, edge breaks, depressions, and rutting. The diagram below illustrates the process. After the area is filled with asphalt emulsion and aggregate mix, the surface is covered with a thin layer of uncoated aggregate. No compaction is required since the compaction is achieved as the hole is filled from the bottom to the surface.