|
|
Posted by MoparNorm [71.110.251.13] on Sunday, November 14, 2010 at 10:56:12 :
In Reply to: Re: OT World Trade Center Steel,?? posted by Hemimech [68.188.184.28] on Saturday, November 13, 2010 at 23:25:46 :
Great link!
Contained within the minutia and mundane, is the reason the towers fell straight down. If you are smarter than Rosie O'Donnell you can figure it out.... = )
"The floors supported their own weight, as well as live loads, provided lateral stability to the exterior walls, and distributed wind loads among the exterior walls. The floors consisted of 4 inch (10 cm) thick lightweight concrete slabs laid on a fluted steel deck. A grid of lightweight bridging trusses and main trusses supported the floors. The trusses had a span of 60 feet (18.2 m) in the long-span areas and 35 feet (11 m) in the short span area.[47] The trusses connected to the perimeter at alternate columns, and were therefore on 6 foot 8 inch (2.03 m) centers. The top chords of the trusses were bolted to seats welded to the spandrels on the exterior side and a channel welded to the core columns on the interior side. The floors were connected to the perimeter spandrel plates with viscoelastic dampers, which helped reduce the amount of sway felt by building occupants. "
Follow Ups: