In the mountain of wreckage that was the 12-million-sq-ft World Trade Center, hundreds from the construction industry have been working in shifts around the clock since the Sept. 11 plane attacks on the 110-story twin towers. They are fighting a multiheaded monster never before encountered. Contractors have been mobilizing to move an estimated 1.2 million tons of rubble and debris, which could take six months to a year to untangle and remove. Engineers have been "on-call" to help them design supports for heavy equipment. Other engineers have been designing a'tieback system for the complex's slurry wall foundation, now partly packed with twisted steel from the towers. And even more have been combing surrounding buildings to assess damage done by the collapse of the towers.
展开▼
