The Fifty-Nine-Story Crisis

The weakest joint, he discovered, was at the Citicorp building’s thirtieth floor; if that one gave way, catastrophic failure of the whole structure would follow. Next, he took New York City weather records provided by Alan Davenport and calculated the probability of a storm severe enough to tear that joint apart. His figures told him that such an event had a statistical probability of occurring as often as once every sixteen years–what meteorologists call a sixteen-year storm. “That was very low, awesomely low,” LeMessurier said, his voice hushed as if the horror of discovery were still fresh. “To put it another way, there was one chance in sixteen in any year, including that one.” When the steadying influence of the tuned mass damper was factored in, the probability dwindled to one in fifty-five–a fifty-five-year storm. But the machine required electric current, which might fail as soon as a major storm hit.