Potholes can become major safety issues if they are not fixed. Therefore, it is important to rely on contractors to fix this type of problem on the roadways. The holes may take the form of various shapes and sizes, and may be patched with either cold patch or hot patch materials.
Water Is the Culprit
Roadway holes of this type are triggered by expansion and contraction of groundwater after rainwater has seeped under the pavement. When the water freezes, it expands. As a result, the frozen water assumes more space underneath the asphalt. When this happens, the pavement in turn expands, cracks, and bends – all of which weaken the surface of the pavement.
A Continued Cycle
When the ice begins to melt, however, the pavement contracts. As soon as this occurs, gaps and voids begin to appear. If water gets into the openings again and becomes trapped, the process of expansion and contraction reoccurs, thus weakening and cracking the pavement.
What Happens If Salt Is Applied
To compound the problem, the weight of vehicles that pass over weak spots in the roadway causes the asphalt to become displaced or broken down even further, which triggers the formation of hazardous potholes. If salt is used, it reduces the temperature for freezing. Therefore, an artificial freeze-and-thaw cycle is created that leads to more surface damage.
Fixing the Roadways
That is why surfacing contractors in Norwich often work on the roadways in the late winter or early spring. Since the temperatures fluctuate more frequently above and below the freezing point then, there is more need for pothole repairs.
A Quick Review of the Process
So, the development of a pothole begins when rainwater sinks through the cracks of weakened asphalt. The water is absorbed by a mix of gravel, rock, and sand – all of which are used as structural support in the construction of a road.
When vehicles pass over the road, they force water through the roadbed. Because the roadbed is soggy, it begins to erode. The asphalt then sinks into the degraded parts of the roadbed. This activity leads to cracking when vehicles pass over the pavement. Eventually, chunks of pavement become unattached. Therefore, you might say that a pothole is a product of cracking, water, and temperature extremes that are brought on by the cold and the sun.
Hot Patching and Cold Patching
Old methods for pothole repair traditionally involved a hot mix. However, because a truck can only hold heat for a certain amount of time, it can lead to a waste of product. To enable better cost-efficiency then, a cold mix asphalt is frequently used now. This material can typically be stockpiled for as long as a year and employed whenever needed. Cold patching can still be used when water is on the roadway as well. This type of patching material is often preferred for use, as it can be driven on right after it is applied. If a hot mix is used, a wait time of two to four hours must be observed before a pavement can be driven on. Cold patching has also been found to last longer, meaning repairs do not have to be made as frequently.