One thing I’ve wondered about is what would have happened if for whatever reason (flight was delayed, they accidentally crashed the plane before it got near the towers, etc.) the terrorists had failed to hit the second tower and only the first one collapsed.
Would they have left the other one standing? Would the debris from the one tower falling have damaged the other building beyond repair or messed up the foundation to the point where it was no longer structurally sound?
Either way of course, the tower would have been unusable for quite awhile after the attacks on account of all the wreckage surrounding it.
But don’t forget, a building that is purposely imploded isn’t full of plate glass, drywall, filing cabinets, office chairs etc. It’s mostly framework and concrete. There would be considerably less crap to go flying around. If they were going to take it down that way, it would have been cleaned out first. Sure, there would still be some fallout, but not nearly as much. I would think setting up some heavy (and well braced) plywood as far back as they could, say 30 or so feet high would have directed most of it upward instead of directly at the nearby buildings.
I have wondered if, had they not collapsed, how scary that might have been.
The towers actually performed pretty well considering their structural damage. A lot of the supports on one side were bashed out.
Had the towers stood I wonder how they’d manage when the first good storm with reasonably strong winds came along. The biggest force a skyscraper experiences is its wind load.
And of course there is a helluva lot of weight pushing down too.
Get a good wind, start them swaying (skyscrapers all sway…they are made to do so) and I would be very scared to be anywhere near them.
Getting equipment and material up there to shore them up would be a huge problem too. It’d take weeks to sort out even for the most kludgy of temporary reinforcement.
They’d have had to evacuate all the surrounding area till that was sorted out and that could have taken a long time.
You are right though that once something fails and the collapse starts that is the end of it. The whole thing will come down.
Pretty sure those minimize sway but do not stop it 100%.
I also thought these were features of buildings in earthquake prone areas. The damper will stop the more violent swaying from an earthquake and the building won’t fall down.
I am unaware of any buildings in Chicago with one (there may be but I always assumed the added cost was not worth it…the sway in most buildings is not severe enough to be very noticeable to residents of the building and structurally they handle it fine). I doubt New York would bother either.
I was watching a show on the construction of the new WTC-1 and there was no mention of one and that building is being built amazingly strong. If a plane hits this one akin to 9/11 the damage would (of course) be severe but this one almost certainly will stay standing. It has other features too…the base is near solid concrete and steel for the first 200 feet to protect against ground attacks. The base is a veritable bunker. The concrete is also supposedly the strongest ever made.
Both cities have buildings with TMDs. In fact, Park Tower in Chicago is the first building to be designed with a tuned mass damper in mind. Wind loads are more significant than earthquakes loads when you get tall enough.