IN THE grand scheme of things, potholes may seem like a trivial problem. But tell that to the many mayors and local politicians whose success is judged by their ability to keep roads free of them. One such, Alfonse D’Amato, an American politician, was nicknamed “Senator Pothole” by his grateful constituents.
Most potholes start as small cracks in a road’s surface, which allow water to seep in. In winter, when the water freezes, it expands, widening the crack. If the water repeatedly thaws and refreezes, the hole can grow quickly, especially since cars will worsen the damage as they drive over it. Small potholes are a nuisance; big ones can damage cars, and even cause fatal accidents.
Better, then, to fix them while they are still small. In practice, that is tricky. In America, for instance, both state and federal governments find potholes by manually examining video footage of the country’s 4.12m miles of roads. That is both...Continue reading
Source: Science and technology http://ift.tt/2Axb81O
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