A pot hole can be created in one of two ways. The first is not sealing the lot. When it rains, the water runs off your parking lot and slips into the crevices, getting underneath your asphalt. When this occurs, the water flows out underneath your asphalt and carries the base of your parking lot (rock) with it. This causes an air pocket which weakens the area underneath your asphalt, where it will collapse, creating a pothole. In winter the water can also flow under the asphalt where it freezes and thaws each night, creating more cracks and weak points in the asphalt.
The second way it happens is during the installation of your parking lot. The installer doesn't put the proper amount of rock base in certain areas which leaves those areas weakened, since 90% of the strength of your asphalt is the base rock . As soon as a heavy vehicle passes over this area it collapses and creates a pot hole or sink hole because the base underneath your asphalt wasn't properly installed.
The correct way to repair a damaged area in your asphalt is to cut the perimeter of the pothole out with a walk behind saw and remove the old asphalt. Once removed, we examine the base and repair it to the proper compaction ratios. Once the base is repaired and compressed properly, we put a primer on the edges (this binds new asphalt to existing asphalt cut edges). We then install a hot mix asphalt in the cut out section and roll down the asphalt with a roller.