Study: Fire caused WTC collapse
Following a three-year investigation, a government agency concludes that fire caused to the collapse of the 47-story Building 7 in the World Trade Center complex.
The Commerce Department’s National Institute of Standards and Technology (NIST) has concluded that the 47-story World Trade Center (WTC) Building 7 collapsed on Sept. 11, 2001, primarily due to fire--the first known instance of fire leading to the complete collapse of a tall building.
“Heating of floor beams and girders caused a critical support column to fail, initiating a fire-induced progressive collapse that brought the building down,” said NIST WTC lead investigator Shyam Sunder. “Video and photographic evidence, combined with detailed computer simulations, show that neither explosives nor fuel oil fires played a role in the collapse of WTC 7.”
The report pointed to one key factor leading to the collapse: thermal expansion of long-span floor systems at temperatures “hundreds of degrees below those typically considered in current practice for fire resistance ratings.” Also, the report recommended stronger building codes and standards that ensure even in the face of severe fire and failure of fire-fighting systems, buildings remain standing.
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Annual Salary Survey
Before the calendar turned, 2016 already had the makings of a pivotal year for manufacturing, and for the world.
There were the big events for the year, including the United States as Partner Country at Hannover Messe in April and the 2016 International Manufacturing Technology Show in Chicago in September. There's also the matter of the U.S. presidential elections in November, which promise to shape policy in manufacturing for years to come.
But the year started with global economic turmoil, as a slowdown in Chinese manufacturing triggered a worldwide stock hiccup that sent values plummeting. The continued plunge in world oil prices has resulted in a slowdown in exploration and, by extension, the manufacture of exploration equipment.
Read more: 2015 Salary Survey