16-08-2013, 01:49 AM
Lauren Johnson Wrote:Quote:Yes 7 could be a relatively small attack of a few connecting plates and then it's all she wrote.
Are we talking about a relatively small attack of a few connecting plates as in a CD kind of an attack?
As I've said all along for all the towers a CD can do what heat does.. weaken and destroy the integrity of the frame. When that gone, load paths are caput and the mass drops.
We don't have evidence of what attacked the connections of 7. We can see in all three collapses 99.999% or the steel only shows connection or joint failures... the steel sections... wide flanges or channels or plates or box are pretty much intact... some boxes had their plate welds fail from mechanically "banging around" in the collapse.
We do see connecting plates and gussets ripped, bent, torn, twists... bolt holes enlarges from pull though in some cases.... fillet welds broken like zippers.
The conclusion is the connections were the weak links... they failed and the frame could not perform. We can't see exactly what destroyed or how the suspect connections... those that were in the *initiation* region failed... if we had evidence of them... it's like we could see if it was a bomb or some cutter device. I couldn't tell, but I am sure others can who know how. I do know no conclusive evidence of device destroyed connections have been presented by those that claim CD.
Does that answer your question about my use of the term "attack"?