Why aren't the WTC tower construction drawings publicly available?

[Architect]

See this?

http://i55.photobucket.com/albums/g157/kookbreaker/ComcastTower1.jpg

Its the Comcast building presently under construction in Philadelphia. When completed (its much further along than shown in the photo) it will be the tallest building in Philadelphia.

See that thing in the center? Its concrete. Why? The lessons of the Towers were learned. Probably even before NIST was concieved.

Stop making up excuses for intruding on private property. Conspiracy freaks have been exclaiming for years that is they get ahold of 'X' then they'd be satisfied. This has never happeded, ever.

In fact, remember when troothers said 'just release the videos from around the Pentagon and we'll shut up'. They were released, they showed nothing as they were not pointed at the Pentagon, and the troothers never shut up.

One of my contacts at Arup's recalls their being criticism of the WTC design in the 60s and 70s because it was felt to be too fragile. Certainly lightweight cores were no way universally adopted, especially in Europe although I would note that the US has generally led the way in tall buildings design ever since the days of Louis Sullivan.

But even a concrete core might be vulnerable; for example is it bolted pc panels, which obviously have joints, or an in-situ solution where staggered reinforcment breaks and the like arguably provides a stronger solution?

This picture of the Comcast building is intriguing because it is quite a remarkable extent of free-standing core, and one wonders what additional design measures were included in order to permit such an erection sequence. On my projects we wouldn't generally go more than 7 or 8 stories above the outer structure, but we don't normally have any requirement to do so anyway.

ETA: Stock picture of a project I worked on under construction (mods to note that it's watermarked, etc. to avoid copyright infringement issues):

 

[kookbreaker]

If it helps, here is another shot taken on the same day.

According to some, each floor used something like 800 yards of cement. A cement mixer carries somethig like 10 yards. This resulted in a brief shortage of concrete in Philly for a while.

 

[Architect]

According to some, each floor used something like 800 yards of cement. A cement mixer carries somethig like 10 yards. This resulted in a brief shortage of concrete in Philly for a while.

[cough] concrete [cough]

 

[kookbreaker]

[cough] concrete [cough]

 

[Newtons Bit]

One of my contacts at Arup's recalls their being criticism of the WTC design in the 60s and 70s because it was felt to be too fragile. Certainly lightweight cores were no way universally adopted, especially in Europe although I would note that the US has generally led the way in tall buildings design ever since the days of Louis Sullivan.

But even a concrete core might be vulnerable; for example is it bolted pc panels, which obviously have joints, or an in-situ solution where staggered reinforcment breaks and the like arguably provides a stronger solution?

This picture of the Comcast building is intriguing because it is quite a remarkable extent of free-standing core, and one wonders what additional design measures were included in order to permit such an erection sequence. On my projects we wouldn't generally go more than 7 or 8 stories above the outer structure, but we don't normally have any requirement to do so anyway.

ETA: Stock picture of a project I worked on under construction (mods to note that it's watermarked, etc. to avoid copyright infringement issues):

I'm doing an eight story office building at the moment, we're using cast-in-place concrete shear walls for the lateral system (in the core). There are pre-cast panels, but only for the exterior facade. I do not think that pre-cast is used for structural elements much these days.

As an aside: Quite a bit of the work that I do is structural renovations of old buildings (1930's to 1980's). Many of these buildings are a part of a large national laboratory. Very few of the existing plans we work with are actually in a CAD system, they're almost all hand-drawn. And this is a government job for a hi-tech installation.

 

[AZCat]

I'm doing an eight story office building at the moment, we're using cast-in-place concrete shear walls for the lateral system (in the core). There are pre-cast panels, but only for the exterior facade. I do not think that pre-cast is used for structural elements much these days.

As an aside: Quite a bit of the work that I do is structural renovations of old buildings (1930's to 1980's). Many of these buildings are a part of a large national laboratory. Very few of the existing plans we work with are actually in a CAD system, they're almost all hand-drawn. And this is a government job for a hi-tech installation.

How do you guys handle that? Do you re-draft the part of the structure in proximity to your work or is there another way to deal with existing structures?

 

[Architect]

How do you guys handle that? Do you re-draft the part of the structure in proximity to your work or is there another way to deal with existing structures?

Yup

 

[Gravy]

Not a continuing collapse. The problems I mentioned above are why a continuing collapse is improbable. Without enough of an initial impulsive load where would the energy come from for that to occur?

Here's why I mentioned that. You said the onset of collapse was sudden, and that it should have been gradual if caused by fire, but that you believe the inward bowing of the exterior walls was caused by sagging of the core columns.

As I'm sure you know, the NIST report does show sagging of core columns, with redistribution of their load to the exterior via the hat truss.

As I'm sure you also know, bowing of the exterior columns is visible within 18 minutes of the south tower aircraft impact, and in the north tower bowing was reported on the scene at least 7 minutes prior to collapse.

I'm sure you're also aware of structural instability reported by witnesses inside the north tower.

So, the collapses were gradual. They began when the planes hit and accelerated when the sagging structures could no longer carry the loads above. I look forward to reading your paper that refutes NIST's science with your own. You'll probably want to read their reports first.

 

[Architect]

I'm doing an eight story office building at the moment, we're using cast-in-place concrete shear walls for the lateral system (in the core). There are pre-cast panels, but only for the exterior facade. I do not think that pre-cast is used for structural elements much these days.

We typically use in-situ r.c. but I've seen a p.c. one going up quite recently on a six storey structure near the office. Caught my eye because it's a while since I'd seen one.

As an aside: Quite a bit of the work that I do is structural renovations of old buildings (1930's to 1980's). Many of these buildings are a part of a large national laboratory. Very few of the existing plans we work with are actually in a CAD system, they're almost all hand-drawn. And this is a government job for a hi-tech installation.

I wasn't trained in CAD at uni (1986-92) and didn't have to learn until about 94........Autocad 11, no less!

 

[AZCat]

Yup

Ahh, thanks. That's what we do (mechanical) but I didn't know if structural did this also, because their drawings are usually a lot more complex (at least to me). All I have to do is measure the dimensions of some mechanical rooms.

 

[Tony Szamboti]

Here's why I mentioned that. You said the onset of collapse was sudden, and that it should have been gradual if caused by fire, but that you believe the inward bowing of the exterior walls was caused by sagging of the core columns.

As I'm sure you know, the NIST report does show sagging of core columns, with redistribution of their load to the exterior via the hat truss.

As I'm sure you also know, bowing of the exterior columns is visible within 18 minutes of the south tower aircraft impact, and in the north tower bowing was reported on the scene at least 7 minutes prior to collapse.

I'm sure you're also aware of structural instability reported by witnesses inside the north tower.

So, the collapses were gradual. They began when the planes hit and accelerated when the sagging structures could no longer carry the loads above. I look forward to reading your paper that refutes NIST's science with your own. You'll probably want to read their reports first.

My contention is that the perimeter column bowing was caused by core column collapse not sagging.

No, I don't know that the perimeter column bowing occurred 7 minutes before the North Tower collapsed. There were many videos of the towers burning and if you could show me a video showing the bowing of the perimeter columns, with the antenna mast and roof line also visible, minutes before collapse, then I would believe it was not the collapse of the central core that caused this bowing. Right now your attempted proof is that it "was reported" that the perimeter columns were bowing minutes before collapse. Those towers were being covered from every angle on video so saying it "was reported" doesn't hack it.

The collapses certainly do not appear gradual on video. The comment concerning witness remarks of structural instability inside the towers is not defined as to what areas are being discussed. This comment means nothing as to whether there was core column sagging and perimeter column bowing in the areas where the collapse initiated, minutes prior to the actual collapse.

I have read the NIST report concerning what they say caused the collapses and I don't agree with them and am refuting them as we speak. It is a shame they didn't test for explosive residue. That should have been done no matter who you think did it, as the firefighters mentioned seeing, feeling, and hearing explosions. It is really a very sore spot for the credibility of their investigation.

 

[uk_dave]

That should have been done no matter who you think did it, as the firefighters mentioned seeing, feeling, and hearing explosions. It is really a very sore spot for the credibility of their investigation.

Yeah, we watched a plane fly into the building at high speed and then an unfought fire until the tower collapsed. Of course they should have checked for explosive residue, makes perfect sense

 

[DGM]

Yeah, we watched a plane fly into the building at high speed and then an unfought fire until the tower collapsed. Of course they should have checked for explosive residue, makes perfect sense

And the NTSB should have reassembled the planes to determine why they crashed.

 

[Gravy]

My contention is that the perimeter column bowing was caused by core column collapse not sagging.

No, I don't know that the perimeter column bowing occurred 7 minutes before the North Tower collapsed. There were many videos of the towers burning and if you could show me a video showing the bowing of the perimeter columns, with the antenna mast and roof line also visible, minutes before collapse, then I would believe it was not the collapse of the central core that caused this bowing. Right now your attempted proof is that it "was reported" that the perimeter columns were bowing minutes before collapse. Those towers were being covered from every angle on video so saying it "was reported" doesn't hack it.

The collapses certainly do not appear gradual on video. The comment concerning witness remarks of structural instability inside the towers is not defined as to what areas are being discussed. This comment means nothing as to whether there was core column sagging and perimeter column bowing in the areas where the collapse initiated, minutes prior to the actual collapse.

I have read the NIST report concerning what they say caused the collapses and I don't agree with them and am refuting them as we speak. It is a shame they didn't test for explosive residue. That should have been done no matter who you think did it, as the firefighters mentioned seeing, feeling, and hearing explosions. It is really a very sore spot for the credibility of their investigation.

"Refuting them as we speak?" You owe me a new spleen, which I just ruptured while laughing.

For someone whose work on this subject has been published, you are astoundingly ill-informed.

You can read all about the progression of bowing in the towers in NIST NCSTAR 3-C. But you already knew that, didn't you, being that it's the

FOURTH TIME

that I've asked you to read that document.

You'll see many more photos of the bowing in both towers, with times listed, in NCSTAR 1-5A, and you'll read NIST's calculations of how the buildings responded to the bowing in NCSTAR 1-6.

Why not start today?

P.S. In your next post I expect to see the names of firefighters who were there who believe there were explosives in the towers.
​

 

[Architect]

Realdeal

Given that my post addressed your OP, I wondered whether you had tended to respond?

 

[Kage]

Answer this question wise guys (meaning Jonnyclueless and Wildcat). If you have the same volume of water vapor laden air and completely dry air at the same temperature which is heavier?

I'm not either of those guys but dry air is more dense than moist air. What does this have to do with anything?

Even if the load from the top section crashing down on the botton section was twice normal (really, really doubt that) do you believe that the building should have been able to support that? Are you one of those 3X redundancy people?

 

[BeAChooser]

if you could show me a video showing the bowing of the perimeter columns, with the antenna mast and roof line also visible, minutes before collapse, then I would believe it was not the collapse of the central core that caused this bowing.

http://www.skyscrapersafety.org/html/article_20040619.html " In the case of the north tower, police chopper pilots reported seeing the warning signs - an inward bowing of the building facade - at least eight minutes before it collapsed at 10:29 a.m."

http://quote.bloomberg.com/apps/news?pid=10000087&sid=aCuh.ATdfOXc&refer=top_world_news "At 10:06 a.m. that morning, an officer in a police helicopter reported that ``it's not going to take long before the north tower comes down.'' This was 20 minutes before it collapsed. In another radio transmission at 10:21 a.m., the officer said he saw buckling in the north tower's southern face, Shyam-Sunder said. The report includes photographs taken from police helicopters showing the bending columns."

http://www.geocities.com/factsnotfantasy/WTC2EastFace921.html "East Face of WTC 2 - 9:21 am, Maximum inward bowing of approx. 10 in. (18 min after impact)" There's a photo of the bowing.

http://members.tripod.com/toolateforregrets/WTC2EastFace953.html "East Face of WTC 2 - 9:53 am, Maximum inward bowing of approx. 20 in" There's a photo of the bowing.

http://members.tripod.com/toolateforregrets/WTC2EastFace958.html "East Face of WTC 2 - 9:58 am, Inward Bowing of Perimeter Columns Seconds Before Collapse" There's a photo of the bowing.

http://www.geocities.com/factsnotfantasy/WTC1SouthFace1023.html "South Face of WTC 1, 10:23 am, Inward bowing Max bowing of 55 in." There's a photo of the bowing.

The following video proves there was bowing at least seven seconds before the collapse began.

http://video.google.com/videoplay?docid=-5405555553528290546&q=WTC&pl=true

 

[Tony Szamboti]

Yeah, we watched a plane fly into the building at high speed and then an unfought fire until the tower collapsed. Of course they should have checked for explosive residue, makes perfect sense

sarcasm with no basis

 

[Tony Szamboti]

"Refuting them as we speak?" You owe me a new spleen, which I just ruptured while laughing.

For someone whose work on this subject has been published, you are astoundingly ill-informed.

You can read all about the progression of bowing in the towers in NIST NCSTAR 3-C. But you already knew that, didn't you, being that it's the

FOURTH TIME

that I've asked you to read that document.

You'll see many more photos of the bowing in both towers, with times listed, in NCSTAR 1-5A, and you'll read NIST's calculations of how the buildings responded to the bowing in NCSTAR 1-6.

Why not start today?

P.S. In your next post I expect to see the names of firefighters who were there who believe there were explosives in the towers.
​

You conveniently left out the video showing the bowing which I asked you about. Having trouble finding one? You make the claim that the perimeter columns in the North Tower were reported bowing 7 minutes before the collapse. If that is true we should see it on videos. I don't want to see photos. They don't prove a time frame prior to collapse, and could easily be taken as a still from the point just prior to collapse of the perimeter but after the central core had started to collapse. There is massive amounts of video of the North Tower starting from not long after it was hit until after it collapsed to the ground. If those perimeter columns had been bowing 7 minutes before the collapse we should see it on video. I have read NIST's attempt to explain the collapse being due to the bowing of the perimeter columns and seen their photos. I am unconvinced. I believe that the bowing occurred in the perimeter columns due to central core collapse and that there was no bowing of the North Tower columns until the central core began to collapse.

For the names of firefighters who testified in the oral histories about seeing, hearing, and feeling explosives see Professor David Griffin's article "Explosive Testimony"
http://www.911truth.org/article.php?story=20060118104223192

and Professor Graeme Macqueen's article concerning the oral histories
http://www.journalof911studies.com/articles/Article_5_118Witnesses_WorldTradeCenter.pdf

BTW, your sarcasm without any reasoning to go along with it doesn't qualify as legitimate argument.

 

[Tony Szamboti]

I'm not either of those guys but dry air is more dense than moist air. What does this have to do with anything?

Even if the load from the top section crashing down on the botton section was twice normal (really, really doubt that) do you believe that the building should have been able to support that? Are you one of those 3X redundancy people?

You answered right about the dry vs. moist air question. I only asked to see if they would answer a technical question.

Yes, I believe that if a collapse could have even occurred due to fire weakening, and the impulsive load was 2G's or less, the collapse would have arrested. What do you think the impulsive load was? Please show some rough calculations if you can. I'm not asking to trick you or trying to be a smart alec I would just like to have a sound discussion of the mechanics which would have been taking place in the collapse. The buildings were only supporting 33% of their capacity on a low wind day with no earthquakes. However, that isn't the whole story as the factors of safety were different concerning gravity only for the core and perimeter. The central core columns had a minimum factor of safety of 1.67 and supported 60% of the gravity load, the perimeter columns had a factor of safety of 5.00 when considering gravity only and handled 40% of the gravity load.