Buckling on an asphalt driveway can create a bumpy or wavy surface. Not only is it uneven and unpleasant to drive on buckled asphalt, but it can also decrease the useful life of the paving.
Causes of Buckling
A few different issues can lead to buckling. If the paving is newer, then the cause could actually lie in a construction error. A weak base that doesn't provide sufficient support or that develops air gaps beneath the asphalt can cause the asphalt surface to buckle and dip. This type of damage usually appears within the first few years of installation.
The other common cause, at least on a driveway, is weathering damage. UV rays from the sun break down the adhesive components in the paving that hold that asphalt aggregate together. Increased porosity of weathered asphalt also allows for more water absorption. This type of wear doesn't occur evenly across the surface, so the weaker weathered areas may buckle due to the now varying surface strength of the paving material.
Prevention and Maintenance
Preventing buckling is much more cost effective compared to trying to fix a problem later. The single best way to reduce the chances of buckling damage is to seal coat the driveway every few years. This consists of painting the surface with a seal coating medium, which is a mixture of asphalt, binders, and sealants that protect against weathering.
Further, any small cracks or similar damages need to be fixed right away so that they don't become larger or allow moisture into the paving. Patching is best done with a hot flexible asphalt mix. Additives to the asphalt make the patch somewhat flexible so it can expand and contract with the paving, which helps prevent future buckling.
Options are much more limited once buckling has occurred. If the issue is with the base material, it may be necessary to remove the driveway and rebuild it from the base up. This is because any damage will quickly return following a repair if the faulty base isn't repaired.
If only a small area has buckled, it may be possible to only cut out that section and replace it. Keep in mind this repair will likely be visible. If the buckling has only penetrated the surface of the asphalt, repair may only require grinding down the surface and applying a new top layer of asphalt.
Contact a paving contractor in your area if you need more help with buckling pavement.