A professor of Civil Engineering at UC Berkeley presents his analysis of why the World Trade Center towers collapsed after being hit by jetliners. This article also provides an overview of the history and structural system of the towers.
"The World Trade Center's twin towers were the tallest buildings in the world at the time of their opening in 1970. They each stood 110 stories and more than 1,300 feet tall. They are the dominant features in an enormous office complex totaling more than 9 million square feet of office space and together make up one of the most recognizable architectural landmarks in the world.According to Gregory Fenves, a professor of Civil Engineering at the University of California at Berkeley, the planes weakened the buildings' structures at key points. Fenves, working on information gleaned from preliminary TV reports, stressed that he was speculating. He said that if the planes had hit the structures higher, they could have merely damaged their tops; if they had hit lower, they would have been up against the enormous weight and resistance of the base of the buildings."
Thanks to Abhijeet Chavan
FULL STORY: Why the towers collapsed
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