Shanghai's futuristic skyline--the city has more than 900 high-rises, with hundreds more under construction--is one of the most potent symbols of China's economic rise. But the materials undergirding all that growth might be shakier than anyone can imagine. In March, the English-language Shanghai Daily reported that fully half of the steel sold to construction companies in Shanghai's wholesale markets failed basic quality tests. Nearly a quarter of the tested samples failed tension tests, meaning structures built with them would not be able to withstand earthquakes and would be more likely to decay over time.
Of the 52 batches of steel tested by the Shanghai Industrial and Commercial Administrative Bureau, 27 were too light to meet China's legal standards. Some batches were nearly five times lighter than the legal standard, meaning that they were less than the weight of iron, steel's primary ingredient. "If your steel is less than the weight of iron, that's pretty incredible," says Christopher Earls, professor of civil engineering at Cornell University. "That means you're replacing the iron with something else, so what you have isn't really steel at all."
The bureau ordered construction sites using the inferior steel to halt work, but, troublingly, did not publicly reveal where it was being used. Adam Minter, a Shanghai-based journalist who blogged the story after it broke, asked, "What will happen to twenty-year home mortgages taken out on Shanghai apartments which will only last--structurally--for ten years? At some point, I'm pretty sure this is going to become an issue." After the collapse of substandard schoolhouses during this year's Sichuan earthquake, tremors of which were felt in Shanghai, the prospect of something similar happening to an urban high-rise isn't an issue anyone should take lightly.
http://www.foreignpolicy.com/top10-2008/index7.html
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