Viscoelastic! lol. Now you're talkin' the language! Actually the floor truss top chords were attached to the seats in the standard way - welded. Only the bottom chords of the trusses had the viscoelastic dampers - which is really nothing more than a big rubber washer. The bottom chord has a big plate welded onto it. That plate sits between 2 layers of the rubber, which in turn sits in a big welded C-channel piece. I think it was a C-channel, anyway. But you are correct. The bottom chords had no hard weld connection.mikemc wrote:The video simulation was sensible to me, but I agree that more of the building would slide down above the area of the initial collapse before the whole thing came over. It would fall not like a tree, but like a pile of bricks, to the side in an arc, still covering a very wide area.LoopStationZebra wrote:That's exactly right.Green Lemon wrote:I guess with so much force acting in one direction, there was nothing to shift it to a lateral trajectory.
Even then, under what circumstances would there be any lateral trajectory? The answer is probably very few. Unless Godzilla or that cool creature from Cloverfield actually leaned against the entire structure at once.
In the towers, the pancaking of the floors is very understandable.
The utter disappearance of the steel core is less very understandable. What caused that to fall apart completely?
 the pancaking is understandable given the failure of the outer shell. The outer shell was pretty robust, though also. Why did it fail throughout the structure? I wonder if that was caused by the fact that the floors were attached to the outer shell by a viscoelastic joint, that enabled the individual floors to more independently of the shell in order to counteract swaying caused by the wind. In the case of the impact, the sway was coming from the *inside*.
Whoa. I need to go and play some music now.
@Green Lemon, no prob. It would be cool if there was a structural engineer in the house, though. We're exposed to this stuff and have some knowledge, but those guys have the real chops.