For a nation that worships cars, the U. S. has been remarkably neglectful of its roads. A drive down today's highways presents a relentless stream of potholes, ruts, and lanes closed for resurfacing. The sad fact is that Europeans, with their smooth autobahns and motorways, make stronger roads than Americans do.
But that may soon change. U. S. scientists supported by the National Research Council's Strategic Highway Research Program have made a fundamental discovery about asphalt that could lead to better roads--without the jump in costs it would otherwise take to match European performance. Paving gurus used to picture asphalt as discrete lumps embedded in a sticky gel. But the new findings show that it's more like strands of spaghetti that are bound together and topped with sauce, says SHRP asphalt-program manager Edward Harrigan. With this insight, researchers are recommending asphalt specifications that they hope will avoid problems such as cracking and rutting.