Raveling is a major problem on asphalt paving, whether it's a driveway, parking lot, or road. Asphalt consists of asphalt binder along with stone aggregate. Over time, the binder can break down or dry out, causing the aggregate to come loose. Left too long, the asphalt will completely break down.
Recognizing Raveling Issues
In the early stages, it can be easy to ignore the signs of a developing raveling problem. At first, it may just seem like there is more debris like dirt and dust on the asphalt surface. The paving may seem like it's getting bumpier as the asphalt binder in the surface layer shrinks and erodes, causing the aggregate stones to stand out more obviously.
As raveling progresses, larger pieces of stone aggregate will come loose, resulting in pieces of loose gravel on top of the paving. Holes may also start to open up in the paving, developing into cracks and potholes. This is due to moisture penetrating into the disintegrating asphalt and into the holes left behind by the aggregate that has come loose.
Common Causes of Raveling
Raveling primarily affects older paving that has been subjected to weathering for many years. Asphalt can shrink as it ages, pulling away from the aggregate until the stones come loose. Heavy traffic can speed the process, as can exposure of unsealed asphalt to sun, ice, rain, and extreme temperatures.
When raveling affects new paving, the issue was likely at installation. Using the wrong type of asphalt mix or failing to properly compact the paving during installation can increase the risk of raveling. Fortunately, any raveling on newly installed asphalt should be covered under the contractor's installation warranty.
Prevention and Repair Options
Fortunately, it's fairly easy to prevent raveling as long as the paving is properly installed. Keeping the pavement clean helps, as fuel and chemical spills can speed up the raveling process. Sealing the paving every couple of years will slow age and weather-related raveling issues. Sealcoats fill in pores in the asphalt, making it less likely for moisture to loosen the aggregate.
For paving already suffering from the early stages of raveling, repairs are possible. The top surface of the paving is ground down slightly, and then a fresh layer of asphalt is installed over the top. Going forward, sealcoating the asphalt overlay will reduce the chances of future raveling.
Contact an asphalt paving company such as DJs Paving if you notice any raveling issues with your asphalt.