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Name: jana hill
Status: N/A
Age: N/A
Location: N/A
Country: N/A
Date: Around 1993


Question:
What causes potholes?



Replies:
Potholes are caused by the expansion and contraction of water. This mainly occurs during the winter months when temperature is below freezing. A small crack must develop in the road surface to allow water to enter. This water then freezes (water expands when frozen) causing the road surface to bulge, and then thaws, returning it to the original position. Over time, the road surface weakens and the hole expands in size with wear.

wildman jackson


As soon as the first vehicle crosses it, damage begins accumulating in a pavement. Over time, as the pavement is "flexed" by traffic up to 100 million or more times, the pavement will begin to break from fatigue just as a coat hanger that is repeatedly bent will eventually break. This damage typically starts as a single crack where the wheels run on the pavement. Over time, more of these cracks will appear and eventually join to form a distinctive cracking pattern that is often referred to as "alligator" or "chicken-wire" cracking. Once this type of cracking occurs, if the pavement is not promptly repaired, the structural integrity of the pavement is lost and traffic will start knocking the pavement chunks loose. At this point, a pothole is born.

Water seeping into the pavement through the cracks can accelerate this process by softening the soil under the pavement. Water expanding and contracting due to freezing can make things even worse. However, potholes can form in any unmaintained pavement, even in dry, hot places like Arizona.

Andrew Johnson


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