Why Should the WTC Towers Suffer Complete Collapse?

Originally posted by Pilgrum
Would this be the pic of a column you referred to earlier?



What's the chance of the plane impact breaking core column welds rather than severing the columns themselves. I doubt such an event was really planned for and could leave the building standing there with a spinal fracture depending on much weaker peripheral steel components acting as splints to hold it in place.

LOL, yeah that's it. I'll have to bookmark it this time.

The plane would definitely need to hit near the welds. But under those circumstances, I could definitely see columns being bent up ALSO.

But given the size of these columns, I'd say they were from the midpoint, and broke apaprt during the fall. They might even be one of the "spires" that stood for a couple of seconds.

reply to post by Richard Gizinu
The shock loading of the full impact would have been conducted to the core via the floor trusses and concrete slabs so maybe the planes didn't have to fully sever the cores by direct impacting those columns. I'd imagine the welds on the higher column sections being much deeper in relation to the thickness of the column walls but that doesn't imply they were any stronger than the welds further down.

Just looking at possibilities

Why it collapsed is so simple its absurd. The World Trade Center was primarily supported by an exoskeleton as opposed to the more traditional approach of deep internal supports. Consider how large those planes were, the holes they punched in that exoskeleton were huge, and one of the planes all but took out a corner. Even without the fire the whole upper floors would have been extremely unstable. It the upper floors had fallen over to the side the rest of the buildings might have been saved but instead they fell straight down and the sheer mass and momentum pancaked the rest.

You don't need planted explosives or hydrogen bombs or aliens to understand it.

Originally posted by Pilgrum
The shock loading of the full impact would have been conducted to the core via the floor trusses and concrete slabs so maybe the planes didn't have to fully sever the cores by direct impacting those columns. I'd imagine the welds on the higher column sections being much deeper in relation to the thickness of the column walls but that doesn't imply they were any stronger than the welds further down.

Just looking at possibilities

I kinda doubt that the trusses would have been able to transfer much energy to the cores. I'd think they just "fold up" or be destroyed and absorb energy. It makes more sense to me that heavier parts like engines and landing gear would have gotten into the core columns and did the damage envisioned by NIST.

But I'd agree about the welds higher up. We see in your photo that the thick steel was welded to about 1/3 depth. With the thinner steel used higher up, I'd think that the welds would be closer to full depth.

Originally posted by grover

You don't need planted explosives or hydrogen bombs or aliens to understand it.

You're forgetting where you're posting.

Some do....

Originally posted by gottago
You could take that copper pipe or wire and drop it from the height of the WTC towers repeatedly, until the end of time, and you will not turn it to particulate.

Exacta-mundo. We could even have them clashing into each other at high rates of speeds all the way down and we still wouldn't get micro-sized particulate from it.

reply to post by grover


Thanks for bringing the over-simplified, arrogant point of view to this thread. I was just dieing to have that occur. I mean why would I want to continue reading productive posts when I could read yours, which told me nothing.

reply to post by Griff


Did NIST mention core column welds at all?

Originally posted by Richard Gizinu
The core took 50% of the gravity loads and the exterior columns took the other 50% of the gravity loads and all the lateral loads.

I believe this to be too simplistic of a description. The core columns would have been exposed to eccentric loading from elevators, stairwells, weight of the transverse bracing beams etc. These eccentric forces create a moment on the member (the same as having a lateral load....not the same magnitude but the same principle). So saying that the columns were designed for only compression load is not correct. They would act like beam-columns and not just columns because of the eccentric loading and therefor would compensate for some of these lateral loads you speak of.

So here's a question - would the core columns need to be welded 100% under those conditions?

Actually, those conditions are probably why they weren't welded along the entire circumference. To give some leeway for tilt on the weaker axis. Just my opinion of why they did that.

Originally posted by Pilgrum
What's the chance of the plane impact breaking core column welds rather than severing the columns themselves. I doubt such an event was really planned for and could leave the building standing there with a spinal fracture depending on much weaker peripheral steel components acting as splints to hold it in place.

Actually, I believe that is what happened to the perimeter columns as well. Well, most of them, some were severed. I'd have to really examine an impact hole photo to be sure, but if I remember correctly, it looks like the connections broke at the impact zone and since they were staggered, that's why it looks like it is a cartoon cut-out.

reply to post by Griff

 

Did NIST mention core column welds at all?

I haven't read the whole report yet. Too busy. But, you have a good question. I haven't seen anything myself as to the welds etc. Anyone else who has read it more thoroughly than I?

[edit on 1/24/2008 by Griff]

reply to post by Richard Gizinu


I've been struggling to get live links to photos on the relevant site for this post (www.sharpprinting.com/911) but it appears totally down right now, but I'll post a link to it when it's back up...

Anyway, your questioning the welds so intently sent me off to do some more reading on the core, and I'll outline what I've come across that seems relevant here.

First off, all the core welds were on the same plane, at the well-known 3-story intervals. interesting in itself, and indicates you really have 3-story units being built/demolished.

Secondly, the site offers a cad analysis of the spire photos which found that for both towers they were almost certainly the inner square box columns, not the outer rows of large rectangular box columns which ran along the length of the cores. The spire most often photographed was, according to this analysis, the inner core at its short side.

If you accept the analysis, and I think it's convincing, that means the massive outer core columns were essentially stripped away. Now my problem with that is that you've got these 3-story units to fail as units, and as you move lower the entire structure becomes stronger. But then you have the spires that show this was not occurring...

BTW, quite independent of its POV (its a truther site) I recommend the site to anyone on either side of the issue, as it has an excellent photo archive of cloes up photos of the columns, construction photos, as well as stills of the collapses and the debris fields.

Does this also not mean that less explosives or incendiary devices would need to be used if focused on the welds?

Everyone talks about how much it would take to severe the columns, but what about at the welds?

The hat truss design to fully stabilize the perimeter walls and core all the way to the lowest sub-level base. To see the design, please scroll down on the following website:

911research.wtc7.net...

Originally posted by Sublime620
Does this also not mean that less explosives or incendiary devices would need to be used if focused on the welds?

Everyone talks about how much it would take to severe the columns, but what about at the welds?

I would think slightly less, but not a big difference.

Besides, you'd still need the "kicker" charges to misalign the columns, and that amount wouldn't change.

reply to post by Sublime620


Whats over simplified and arrogant about it? It only makes sense... the exoskelton is compromised and the whole thing comes crashing down. You don't even need fire weakening the supports to do it. It made sense to me the day it happened while watching it over and over on TV and it still makes sense to me today.

I have yet to come across one single conspiracy theory that comes as close...

...That being said the bush administration's ever increasing power grabs since then certainly makes it look like if they didn't plan it, they certianly benefitted greatly from it.

I am sorry you don't like my opinion but thats not my problem.

reply to post by Sublime620


Yes, I didn't mention this because I wanted to see the reaction first, but that is what the site's author proposes--he looks at the photos of the rectangular core columns and identifies many he believes were deformed at their ends by just such charges.

Originally posted by OrionStars
The hat truss design to fully stabilize the perimeter walls and core all the way to the lowest sub-level base.

But the hat trusses are out of action as soon as the collapse starts; the real question is: How was the core destabilized?

Actually, the cores took almost the entire gravitational load, not just 50% of it. It had to take lateral load on its side of the floors, plus, stabilizing against high wind shear against the perimeter walls and through the space between the steel primary load bearing perimeter walls and steel facade. The hat trusses did more than their fair share holding it all together, from the 107th - 110th floors and straight down to ground and the lowest sub-level base.

The core unit was double steel framing.

The buildings were not simply open tubes inside open tubes. They had to sub-divide office space when more than one company was leasing office space on any floor from the ground up or it was not used as a sky lobby. When some of the picitures are presented with the sun shining through, I have to wonder at what point someone took those pictures. It looks as if no one will ever use those buildings for work or residence. They also need individual offices where executives and management hide out and have private restrooms etc. There is no sign of any offices or sub-divisions in those pictures.

The key to knowing they were not hollow tubes in tubes is to look at the blueprints I have linked in at least a couple of times. Those buildings definitely look internally unfinished when they took those photographs.

Originally posted by gottago


But the hat trusses are out of action as soon as the collapse starts; the real question is: How was the core destabilized?

I am convinced, at this point, it was DEW through anti-gravity and electromagnetic beams. Those can be shot from land, sea, or air.

reply to post by grover


The "exoskeleton" was not primarily responsible for stabilizing the towers. The core base, core and hat truses were. If plane or fire actually had compromised the "exoskeleton", there would have been peeling and toppling/pancaking of the "exoskeleton". The core support frame would have still been standing along with all that additional steel framing inside the cores.