WTC Collapses

And here lies the problem Scott. Your "source" is a anonymous, poorly constructed, freebie homemade webpage that could have been written by anybody. It's not attributed to anyone, and the data is just put out there for us to believe, with no references to where the data came from. Just because it's on the web, does not necessary make it true. I have seen you time and time again take the word of dubious sources as gospel truth. You have to not only look at the data..but see where it's coming from.

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Ah, vertical hallways interupting and such

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. I'll take your word over his. I've never seen the author of that page defend a point; I've definitely seen you do it, however.

 

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This post is in response to Headspin's post 1059 in this thread.

Wait, the source didn't say that the box columns were surrounded by concrete, but rather the reverse- that the steel beams surrounded the concrete. Here's a quote:
"The design was a "tube in a tube" construction where the steel reinforced, cast concrete interior tube, was surrounded with a structural steel framework configured as another tube with the load bearing capacity bias towards the perimeter wall with the core acting to reduce deformation of the steel structure maximizing its load bearing capacity. All steel structures with the proportions of the WTC towers have inherent problems with flex and torsion. Distribution of gravity loads was; perimeter walls 50%, interior core columns 30% core 20%."

 

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I sincerely doubt that. However, as I said, I'll take Headspin's word over this anonymous source.

Well it definitely comes from a truther site, but I agree that references to where the data came from would be very helpful in determining its veracity. Kind of reminds me of the way NIST does many things

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That's true. It just seemed so complex I thought it had to be true. I guess that's how NIST gets a lot of people too...

Wait, wait, time and again? As far as I remember there was only the mini nuke thing before this...

Well if they'd provided their sources I'd have done just that. But since they didn't and the author seemed to speak in an authorative manner, I felt that it was probably right. As I've mentioned, NIST and the mainstream media employs the same technique and it's certainly managed to persuade many people.

 

careful, you start asking questions about "where the data comes from" you might be called a "silly bastard".

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The Structure of the World Trade Center, Round 2, Part 2

This post is in response to the 2nd part of shaman_'s post 643 from this thread.

That's one small step for conspiracy theorists but one giant leap for the truth ;-)! Well, perhaps I'm being a little dramatic

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Well, since Headspin disagrees with some of that source, if he, Tony or psikey agrees with you on this I'll leave it at that unless I get more evidence.

My base was the source I mentioned before, so again if Headspin/Tony/psikey agrees with you, I'll let it rest.

True. Nor does 9/11 Research mention a concrete core in an article dedicated to the design of the twin towers. I certainly trust 9/11 Research more then the other anonymous author from 911review.org.

 

The Madrid Windsor Tower was not compromised by a major aircraft strike so it's not the same, parameters.

Plus it didn't use the same construction techniques as the WTC constructions.

The WTC was a litesteel construction, the Windsor Tower was a beam and girder building, with intervening vertical girders between the core and the outer walls.

The WTC floor plan was a open plan with no support for the horizontal floor beams, except at each end, at the Core and outer wall.

So there is no comparison between the two building techniques, and nothing can be gained from the comparison.

 

neither was wtc7

what exactly do you mean by "litesteel" ?

are you still maintaining the towers were supported by the stupid aluminium-like things in your picture?

 

This wasn't the reason I said you seemed to be a silly bastard or were acting like one. You were baiting and then when the data was provided you refused to look at it and used ridiculous excuses.

Even after you did finally look at the data you had the audacity to state that I wasn't qualified to determine the factors of safety of columns with the loads, column cross sectional areas, and the yield strengths known.

 

Steven Jones debunks some official story claims, Round 2, Part 1

This post is in response to the 1st part of shaman_'s post 648 in this thread.

I've gone over this before, but perhaps when you wrote this I hadn't yet gone over it (this post is something like 400 posts before present after all). Anyway, basically, the 767 wasn't going fully loaded and the twin towers were definitely designed to handle their impacts, according to John Skilling, who some argue was the true lead designer of the towers (as opposed to Leslie).

From what I remember, it wasn't demonstrated, but feel free to provide your alleged evidence (once more?) for me to (once again?) debunk it. I also see that you have handily sidestepped the fact that I've proven my point- Steven Jones has just handily debunked some Bazant and Zou's peer reviewed material and you haven't even batted an eye...

Certainly something that couldn't have happened without syncrhonated explosives, yes.

Sagging floors in a localized area of the buildings don't create a tower that collapses at near free fall speeds, sorry. I constantly marvel at the fact that you fail to question -why- it is that NIST never modelled the actual collapse of the towers, instead leaving things at 'poised for collapse'.

I'm sure Tony or Headspin could really debunk these arguments. As for myself, I'll simply ask if you can provide evidence that the office fires could have collapsed even 1 floor. If you can manage that, I'll be happy to hear evidence on how it would have caused the collapse of the rest at near free fall speeds.

 

You are completely wrong about this litesteel notion. I believe you actually mean lightweight construction. There is a big difference.

The core columns in the towers were either built up box beams, made by welding structural steel plates into the specific shape, or rolled wide flange sections. The perimeter columns were built up box beams, made by welding structural steel plates into the specific shape, joined together by deep spandrel plates welded to them in a horizontal way and creating a moment resisting frame. The perimeter columns had a 5.00 to 1 safety factor for gravity loads and the central core a 3.00 to 1 safety factor for gravity loads.

Most skyscrapers built since the twin towers use a similar construction method to create more open floor space but this does not mean they are weak. The important thing to do in building any structure is to put the material where it needs to be to take the loads while minimizing stress and maintaining stability. Your contention that lightweight construction is what caused the towers to collapse has no basis. What caused the core to collapse? It was not lightweight and could handle three times the load that was on it. There was no deceleration of the upper block so it's load couldn't have been amplified. You need to think seriously about this if you are an honest person.

 

There are some very tall structures made from reinforced concrete but the core columns in the twin towers were not concrete. They were mostly built up box beams made from ASTM A36 structural steel and those that weren't box beams were rolled wide flange I sections made from ASTM A36. The cross sections can be seen at http://wtcmodel.wikidot.com/nist-core-column-data. This data was released by the NIST in the summer of 2007.

 

What is really remarkable is that some still support this theory given the fact that there has been no physical evidence provided to substantiate claims of high steel temperatures in the towers and that 99.5% of the steel was never tested and out of the 0.5% that was very little of it was from the fire affected areas.

The central core was self supporting. It isn't true that it needed anything else to support it. Additionally , why would the neighboring perimeter columns simply collapse when a floor section attached to another column allegedly gave way? The perimeter columns did not give way when their neighboring columns were impacted and cut by the aircraft. That would have put a whole lot more stress and strain on them than a nearby floor section.

 

Wait, neither I or the anonymous source ever said that the columns were concrete- the idea was that there was a concrete core surrounded by steel columns. That may be wrong as well, but I just wanted to set the record straight on what I actually said.

 

They couldn't pour concrete in the rolled wide flange I-section columns and it is unlikely that they filled the box columns. I think there would have been a concern about damaging the welds on the box beams which occurred every three floors. They also didn't need any additional compressive strength as the stress on both the core and perimeter columns from gravity was approximately 11,000 psi and the yield strength of the core columns was 36,000 psi or above. The yield strength of the perimeter columns varied from 36,000 psi to 100,000 psi depending on where they were located. The reason for these higher strengths of some of the perimeter columns was bending resistance to take wind and seismic loads not gravity loading.

 

and i'll say it again, you do not have the experience nor the expertise to determine safety factors in connection with high rise buildings.
nothing audacious about it.

just because i can run a perfect weld on aluminum by no means says i'm qualified to weld pressure vessels does it?

you know where i'm coming from tony, stop being obtuse about it.

 

Now you are just being straight out inane. Maybe your avatar really suits you literally.

I am plenty qualified to determine what those factors of safety on the tower columns were. I am a structural engineer and it is a simple procedure for gravity loaded columns. I explained the calculations in the paper.

I am curious as to what your criteria would be for someone to be qualified to do it. So why don't you tell us? While you are at it tell me what you think I could have gotten wrong.

The obtuseness is obviously not on my side Leopold.

 

i got straight A's in welding school. my teacher even extolled my achievements in a recommendation letter. will NASA let me weld their LOX tanks?


that's why.

 

Tony I am being honest, and I also have a Brother-in Law, who was the president of one of the largest construction firms on the West Coast, and I spent the afternoon on the phone with him asking questions.

He pointed out that the floors of the WTC were laterally braced, and no vertical bracing at all, they were only connected at each end to the Core Column and the Outer Wall, other than that, there was no vertical bracing of the floor support beams.

So when the collapse came, the only support the lower floor had was at each end, and those end supports basically only were designed for load + 15% that is standard, on occasion it is a safety factor of load + 25%, and even only 10 storys coming down on that is far in excess of load + 15% or even load + 25%, and that is with no damage to the structure.

Hell even load + 100%, means that the receiving floor could hold it's self + the next floor above it, not the other 9+ floors, and with every floor collapse, that weight only increased, and the safety margin still stayed at Load + 15%.

He suggested these as a lead:

http://www.usyd.edu.au/research/opportunities/opportunities/415

http://www.usyd.edu.au/research/opportunities/opportunities/417

 

that was one of the innovative features of the twin towers. each floor was almost an acre of uninterrupted floor space that could be partitioned any way the renter deemed necessary.