WTC 7 - was it leaning all afternoon and going to collapse - or is it just an urban myth?

Originally posted by bsbray11
Of what scale? Stop making things up, I just told you I DIDN'T mean rebuilding a whole floor.

You said:

So why didn't they reproduce this in a lab? Why couldn't they even measure the tensions produced, and compare them to the tension required to displace a column so far?

In order to reproduce this, you would need to construct a truss of the required length (60 feet) and subject it to the appropriate conditions. As far as I am aware, NIST used the largest such facility they have access to in conducting their experiments, and it was limited to 35ft. Regardless as I think we have both agreed, this analysis can be carried out analytically.

Here are some quotes from NCSTAR 1-6B:

From the "conclusion" of "2-D Analysis of a Building Frame Under Gravity Load and Fire":
...
Italics were already there, I added the bold part. I wonder if the contradiction was ever resolved beyond the "one possible explanation"?

I'm not sure what exactly you're either stating or implying with this part, if it is just a general point of interest then i share your interest, but I would note you are incorrect here:

This simulation also assumed steel heated to 1273 K, something also not consistent with scientific studies of fire applied to steel frames (and if any studies HAVE shown steel realistically heated to this temperature, let me know -- I know Cardington's tests certainly didn't, and in fact contradict it).

Cardington's tests certainly did. Remember that Cardington used fireproofed columns up to within about 30cm of the connection. The beams in the tests rapidly hit 1000C and above, and sagged markedly. Additionally, this was a test on a beam floor, which has a greater mass than a truss floor. I even wrote a little script to graph the results a while ago and I should be able to locate them if needed, the spreadsheets available with the data should be good enough.

I looked through 1-6C pages 45-52, and saw a lot about the capacities of the connections to take various tensile forces at various assumed temperatures, and theoretical failure mechanisms for the connections themselves, but nothing about the perimeter columns themselves being pulled in.

Well I am not sure what you are after, the whole of NCSTAR 1-6 is devoted to the building's response to fire, and the tensile capacity of the truss seats is of course an important part of modelling that. If you read on you may find what you're looking for, but otherwise it would likely be in 1-6D. I will have a quick look for relevant information also, i don't have any notes specific to this but as you can imagine there's a lot of info to sort through.

After page 77, figure 5-32a shows that a perimeter column is deflected less than one inch by a truss heated to about 450 C, and more and less heat both reduce that deformation. At temperatures and tensile forces much greater than that, the connection itself fails.
...
So, look back over that yourself, and see that I'm getting this right, that a perimeter column is being deflected a maximum of less than 1 inch horizontally by an optimally-heated and sagging truss.

I'm afraid this is incorrect, this section of the report deals with a full floor model, but without all relevant conditions. NCSTAR 1-6D page 37 and 38 explains this. I apologise for not making this clear, I was simply trying to illustrate that the relevant calculations, simulations and analysis was available. I shall compile a more thorough reference list if needed.

The more detailed, global analyses are carried out in NCSTAR 1-6D also, a good place to start for illustrations of the results is page 208 but of course there are several hundred other pages all with relevant information. Once again I feel the need to thank a member of the truth movement for actually being able to read a reference source. It is so nice to be able to refer you to these pages and know you will actually read them instead of simply assuming them to be wrong. I have only one final comment:

especially when the perimeter columns' safety factors are taken into account.

I'd like to try and preempt you claiming 2000% safety margin. I can't guarantee you were going to, but this is a common claim and based off the safety margin for live load, which is limited to wind and normal office movements. The actual safety factors for columns may be found elsewhere in the NIST report, but for the life of me I cannot remember where.

reply to post by tezzajw


Consult the March 2009 issue of FIREHOUSE magazine for article by
Vincent Dunn (retired FDNY deputy chief, author of "COLLAPSE OF
BURNING BUILDINGS") - goes into detail about issue of catrosophic
collapse of high rise buildings using WTC 1 & 2, WTC 7 as examples.

Previously these buildings were viewed as "too big to fail" - it was assumed
that nothing could cause a total failure of the buildings. That assumption
was destroyed by 9/11 - Dunn said that from now on FF must consider
the possibility that a high rise building can totally collapse and that
commanders show look for any signs of building instability preceeding a
collapse.
considered

reply to post by exponent

Yes, the street in front of WTC7 was filled with debris,

What are you talking about? Photographers were climbing all over the debris everywhere.

even firefighters were prevented from approaching it due to collapse risk.

Really, and you have sources for this alleged information or is this something you just made up. So for seven hours no one was allowed near WTC 7. Funny, how photos were being taken all day long from different locations around all three sides of WTC7 yet we are not shown one clear photo of this alleged gash.

This is why there are few good photographs, because it was dangerous and difficult to get them,

Yeah, real dangerous and difficult to get them. Not to dangerous for a helicopter to get!
Helicopters were flying around all day shooting photos what happened to all of those photos. That hazy photo of a showdow doesn’t show anything.

a couple from Steve Spak who was allowed to get close due to being an honourary firefighter.

What does an honorary firefighter have to do with taken photos of the alleged gash on WTC 7? And all he got was two out of focus, or blurred photos.

The Deutsche Bank building did not collapse, and so it has been photographed thousands of times since 911.

We are not talking, how many times the Deutsche Bank was photographed we are talking about WTC 7 and why no visible photos where taken of the alleged gash on the WTC 7.

Originally posted by impressme
What are you talking about? Photographers were climbing all over the debris everywhere.

Then how did is it these photos do not exist? Did the government somehow confiscate the private photos of citizens?

Really, and you have sources for this alleged information or is this something you just made up.

Of course there are sources. It's been a well known fact for many years that a collapse zone was established around WTC7 since the early afternoon. Are you really claiming you know nothing of this?

Yeah, real dangerous and difficult to get them. Not to dangerous for a helicopter to get!
Helicopters were flying around all day shooting photos what happened to all of those photos. That hazy photo of a showdow doesn’t show anything.

That photo is from a helicopter, and it's hazy because the entire building was pouring out smoke. It is still not a shadow no matter how many times you repeat it. Have you found a building that is only 20 feet wide and taller than 7 WTC yet?

What does an honorary firefighter have to do with taken photos of the alleged gash on WTC 7? And all he got was two out of focus, or blurred photos.

He was allowed into areas that non firefighters were not.

We are not talking, how many times the Deutsche Bank was photographed we are talking about WTC 7 and why no visible photos where taken of the alleged gash on the WTC 7.

You talked about it, I responded. Why are you now complaining that we're talking about it?

Your user title says "DENY IGNORANCE" but you seem to be ignorant of even the facts of how shadows work. Perhaps you could sketch for me how a building would cast a shadow that just happens to cover a perfectly vertical single column width section of the tower. I guessed at 20 feet, but you can provide your own figures if needed.

Originally posted by exponent
In order to reproduce this, you would need to construct a truss of the required length (60 feet) and subject it to the appropriate conditions.

Even if there weren't any other ways to test it, it still is untested.

I'm not sure what exactly you're either stating or implying with this part

It's interesting because they failed to produce the deformations they were looking for even though they used more severe parameters. Similar to some of NIST's other computer simulations where they had to ramp up parameters.

Additionally, this was a test on a beam floor, which has a greater mass than a truss floor.

They also used a controlled heat source. I looked back through the data, and some beams did reach 1000 C and a little over with about a half hour of applied heating, but that was as far as anything went and of course it wasn't uniform. The deformations and extra stresses I never had an issue with, it's just a matter of coordinating all these things to getting one of the towers to actually collapse, and the beam connections at Cardington aren't really comparable to the WTC trusses. The heating itself is also something that was uncontrolled and known to be inconsistent within the WTC Towers (ie the fires roamed).

I'm afraid this is incorrect, this section of the report deals with a full floor model, but without all relevant conditions. NCSTAR 1-6D page 37 and 38 explains this. I apologise for not making this clear, I was simply trying to illustrate that the relevant calculations, simulations and analysis was available. I shall compile a more thorough reference list if needed.

What I am looking for, is how much deformation we are looking at from these flimsy trusses pulling on the exterior columns, and how did they prove/establish that this information is credible and conclusive.

The graphs in 1-6C were talking about exactly this kind of deformations, but if somewhere else in the report they manage to prove a greater amount of deformation, again, I'd like to know how they prove it, if it's reproducible, can be reviewed, etc.

And did I not interpret the graphs correctly, that there is an optimum temperature to deflect perimeter columns around 450 C, after which the connections themselves fail? So in other words according to those graphs, for the not-quite-an-inch deformation, the truss had to be in a very particular condition and it didn't just apply greater tension with higher temperature. In fact, greater temperatures had the opposite effect and failed the connections.

especially when the perimeter columns' safety factors are taken into account.

I'd like to try and preempt you claiming 2000% safety margin.

I hope we could agree it would have at least been 2. I've seen it put at 5, too. At any rate, for one thing, I don't trust NIST's word for something, especially when they refuse to release the structural documentation to substantiate their claims. And for another, I DO believe those structures were robust and not just barely holding themselves up.

[edit on 8-6-2009 by bsbray11]

Steve Spak is a well known fire photographer in the New York City/NJ
area.

My best Fire and Rescue images. Spectacular Fires and Rescues taken over 30 years in the NYC metropolitan area. Lots of these photos made the covers of Firehouse, Fire Engineering and WNYF magazines. Many have been published in the NY Daily News, NY Post, Newsday, AP and others.

He is a court officer in Brroklyn. Becuase of his long career as a fire
photographer was familar to many NY police and fire officers - hence
his designation as a "honorary chief" - which allowed him access to
WTC site to take many of the photos showing extent of damage to
WTC 7.

Has often lectured and shown his collection to meetings of local fire
photographers in New York area.

reply to post by bsbray11


Thanks for that. But that doesn't show it from the other angle. It's very wide. If it was leaning just a bit, enough vectors would be going down so to pull it straight down.

reply to post by exponent

Then how did is it these photos do not exist? Did the government somehow confiscate the private photos of citizens?

I asked you the question.

Of course there are sources. It's been a well known fact for many years that a collapse zone was established around WTC7 since the early afternoon. Are you really claiming you know nothing of this?

Besides spouting, you own opinions, how about posting some sources.

That photo is from a helicopter, and it's hazy because the entire building was pouring out smoke. It is still not a shadow no matter how many times you repeat it. Have you found a building that is only 20 feet wide and taller than 7 WTC yet?

It’s a showdow no matter how many times you deny it. Prove it is not? *You can’t!*

He was allowed into areas that non firefighters were not.

So, people were still allowed in front of WTC 7 for whatever reason they wanted right.
Hummm, yet no real clear photos my opinion is there was no gash because it has not been proven yet. If you are convicted that photo that Bones poster early of the showdow that runs perfectly straight is a gash then I want you to prove it to me besides a hazy photograph that LOOKS like a shadow. I don’t care if there is a building across the street or not. What evidences do you have besides that picture and HEARSAY that can prove we are looking at real damaged here. As far as I am concern the photo in question “could” be photo shop.

You talked about it, I responded. Why are you now complaining that we're talking about it?

I never mention how many times photos were taken of Deutsche Bank you need to stop with the disinfo game, in fact what you did was called a red herring.

Your user title says "DENY IGNORANCE" but you seem to be ignorant of even the facts of how shadows work.

So now you have resorted to insults and ridiculing a common trait disinfo use when losing a debate, when they cannot explain the facts.

Originally posted by Gorman91
Thanks for that. But that doesn't show it from the other angle. It's very wide.

So it would be rectangular, not square. And contrary to what you apparently think, you can't consistently tell how a building is going to fall based on what shape it is. If you disagree then I would love to see the field of science that proves otherwise. To date I have never seen building collapses analyzed by what shape the building is. The internal structure maybe, but not just looking at it from the outside.

If it was leaning just a bit, enough vectors would be going down so to pull it straight down.

I don't know what "vectors" you are talking about, but if it were leaning even just a bit, then it has already demonstrated rotational acceleration about a fulcrum, just like WTC2 did before it started falling straight down. There is nothing "pulling" the building down except gravity, and gravity is the weakest force known in nature. The electromagnetic force holding matter together is much stronger and that is the same force that provides the building its rigid structure. To fall straight down is to take the route of the most resistance physically possible, and yet WTC7 accelerated at free-fall. It was not a natural building collapse.

Originally posted by bsbray11
Even if there weren't any other ways to test it, it still is untested.

By that measure yes, but if it can be analysed analytically, would that satisfy you?

I'm not sure what exactly you're either stating or implying with this part

It's interesting because they failed to produce the deformations they were looking for even though they used more severe parameters. Similar to some of NIST's other computer simulations where they had to ramp up parameters.

It's not really possible for me to say what the reasons are for the differences in this study, but I don't feel that it has any bearing on the discussion we're having? I mean it's not the analysis in the NIST report, and obviously very little work has been done to identify the cause of the difference. With regards to NIST, i'd be interested if you could identify a situation where they increased parameters beyond what you consider to be valid.

They also used a controlled heat source. I looked back through the data, and some beams did reach 1000 C and a little over with about a half hour of applied heating, but that was as far as anything went and of course it wasn't uniform. The deformations and extra stresses I never had an issue with, it's just a matter of coordinating all these things to getting one of the towers to actually collapse, and the beam connections at Cardington aren't really comparable to the WTC trusses. The heating itself is also something that was uncontrolled and known to be inconsistent within the WTC Towers (ie the fires roamed).

This is all accurate, but I don't see this as a valid criticism of the NIST report as their models include fire development and spread, the resulting impact of the fire on trusses in both fireproofed and non fireproofed sections, and the eventual deformations and inward pulling forces this produced. They account for every factor you list here in detail.

What I am looking for, is how much deformation we are looking at from these flimsy trusses pulling on the exterior columns, and how did they prove/establish that this information is credible and conclusive.

Well, we know from images that we are looking at up to 55 inches of inward deflection:


How NIST arrived at this through simulation is extremely complex, and I doubt I can summarise it for you here, the entirety of NCSTAR 1-6D is dedicated to this subject. With regards to proving it was credible, I don't know what exactly you expect, but they created accurate models of the WTC, and then tested things like truss heating, fireproofing performance, fire temperatures and spread, heat output etc etc in physical recreations. They then used these results to simulate a much larger scale and discover the effects this had on the towers. Based on these results they then ran more complex simulations on areas that were identified as affecting the structure (truss sagging etc). They found that their model matched many visual identifiers and physical characteristics of the towers collapse. They developed the appropriate exterior inward deflection and failed at a similar point.

I don't really know what to say to you here, because it is a question with such broad scope. The NIST report is extensive as I'm sure you know, and I am not sure what you expect from it in terms of testing and verification. If you can expand on what exactly you'd want out of NIST, perhaps I can tell you what, and why they did it.

And did I not interpret the graphs correctly, that there is an optimum temperature to deflect perimeter columns around 450 C, after which the connections themselves fail? So in other words according to those graphs, for the not-quite-an-inch deformation, the truss had to be in a very particular condition and it didn't just apply greater tension with higher temperature. In fact, greater temperatures had the opposite effect and failed the connections.

Yes this is exactly correct.

I hope we could agree it would have at least been 2.

Indeed this is quite accurate, it varies on a column by column basis and NIST has a good accounting of the 'demand to capacity ratio' for relevant columns.

At any rate, for one thing, I don't trust NIST's word for something, especially when they refuse to release the structural documentation to substantiate their claims.

Do they refuse to release it, or have they simply not released it? I ask because as far as I know structural documentation such as blueprints are copyrighted. I of course would like to see as much information released as possible, but at some point you're just going to have to trust that they're not lying to you. What's to say they wouldn't manipulate what was released? I'm sure you've seen many people claim this for any evidence released.

And for another, I DO believe those structures were robust and not just barely holding themselves up.

Robust is obviously a relative term, they certainly weren't just barely holding themselves up, and there's no doubt that they would have continued to function properly for a long time to come, especially in the case of WTC7. In WTC 1 and 2s case, there was no real critical fault, they may have been underdesigned to survive a serious fire, but this is debated and can be understood given the poor quality of fire simulation when they were designed.

With regards to WTC7, the NIST report concluded that in fact elements of the building's construction were unsafe when subjected to the results of a prolonged fire, they have issued recommendations and they are still being debated as rightly people are arguing that such circumstances are incredibly rare. Nevertheless, WTC7s design was unique, and we're unlikely to see a similar failure for some time, especially considering modern skyscrapers are often built incorporating lessons from it (the new WTC7, the Chinese TVCC).

This is a pretty long post, and I likely won't reply now until tomorrow, my work is done for tonight. I would ask that in your next post, you be as specific as you can when detailing what exactly you would expect from NIST in terms of testing, validation etc.

Originally posted by impressme
I asked you the question.

Then why won't you answer mine? Is it because you have no good answer?

Besides spouting, you own opinions, how about posting some sources.

They were concerned about seven coming down, and they kept changing us, establishing a collapse zone and backing us up.

graphics8.nytimes.com...

I found this by googling "wtc7 collapse zone". Was that too much for me to ask?

It’s a showdow no matter how many times you deny it. Prove it is not? *You can’t!*

Of course I can't prove it isn't a shadow, much like you can't prove there is not a teapot in orbit around Mars. There is no evidence it is a shadow and no building exists which is capable of casting that shadow. There are photos of damage a shadow cannot cause and oral accounts from firefighters of large scale south side damage. The evidence is overwhelmingly in favour of it being actual damage.

So, people were still allowed in front of WTC 7 for whatever reason they wanted right.

No, that's exactly the opposite of what I said.

What evidences do you have besides that picture and HEARSAY that can prove we are looking at real damaged here. As far as I am concern the photo in question “could” be photo shop.

What evidence would you accept? You dismiss photos on a hunch and eliminate eyewitness accounts. There are of course videos of this damage too but if you have eliminated images and eyewitness accounts, what else is left?

So now you have resorted to insults and ridiculing a common trait disinfo use when losing a debate, when they cannot explain the facts.

Funny you should claim I am insulting you when you in the same sentence call me a disinformation agent. Despite the fact that it is obviously meant as an insult, mine was not.

The facts of sunlight are extremely clear and the mechanism by which a shadow is cast is well understood. Here is a challenge for you if you say it is a shadow. Use an online calculator to work out the altitude of the sun as close to WTC7s collapse as you can, then use a pencil to cast a shadow on a flat plane and work out the required height of a building in Manhatten to cast such a shadow.

This is not a demanding task, and identifying the building causing the shadow would lend considerable credence to your theory which at the moment as far as I can see is only supported by your belief that it looks like a shadow.

reply to post by bsbray11


After the fire was permeating throughout the entire structure, gravity became strong enough to pull it down.

Also, the building would probably be leaning a bit considering the fire was strongest only in one area.

Originally posted by exponent
By that measure yes, but if it can be analysed analytically, would that satisfy you?

That depends on how much reproducible data the analysis is based on.

It's not really possible for me to say what the reasons are for the differences in this study, but I don't feel that it has any bearing on the discussion we're having? I mean it's not the analysis in the NIST report, and obviously very little work has been done to identify the cause of the difference.

It was included in the NIST report, and I think given the fact that they had to change certain parameters in their fire simulations to get certain results, we might have another idea as to why they didn't get a consistent result in this particular simulation. Is that not also a reasonable opinion? If they have inconsistent results between two similar cases, that were both reasonable as far as they could tell, then I think that goes to show how fine the lines are that their theories walk.

With regards to NIST, i'd be interested if you could identify a situation where they increased parameters beyond what you consider to be valid.

Jim Hoffman laid out all the changes they made in their cases favorable to structural failure here:

The Report contains a lengthy accounting of how the models performed under various assumptions about the buildings and the planes. One assumption common to all their simulations is the following:

The two Tower models included the core columns, the floor beams, and the concrete slabs from the impact and fire zones to the highest floor below the hat truss structure: from the 89th floor to the 106th floor for WTC 1 and from the 73rd floor to the 106th floor for WTC 2. Within these floors, aircraft-damaged structural components were removed. (p 100/150)
[emphasis added]

Apparently, any structural component estimated to have been damaged to any degree was removed from the model -- as if it contributed nothing to the structure. In other words, if NIST's crash simulation predicted that a column had lost 10% of its load-bearing capacity, it was treated as if it had lost 100% of its capacity.

For each Tower, NIST created two cases. The first set of cases, North Tower case A and South Tower case C, were based on the averages of NIST's estimates of building and plane strength, impact trajectories and speeds, etc. The second set of cases, North Tower case B and South Tower case D, assumed conditions more favorable to the failure of the buildings. The enhancements adopted for Cases B and D over cases A and C are described in the following table:

North Tower South Tower
increase in impact speed 29 mph 28 mph
decrease in approach angles 3º 1º
increase in aircraft weight 5% 5%
increase in aircraft strength 25% 15%
decrease in Tower strength 20% 15%
decrease in Tower live load 20% 20%
increase in Tower fuel load 25% 25%

The Report noted that cases A and C did not produce results matching observations, so cases B and D were selected for use in its four-step modeling.

911research.wtc7.net...

I haven't verified each one of these personally yet but I already knew that they changed Flight 175's impact angle to maximize damage to the core in their models, and that they had to play around with their fire simulations until they finally got the results they were looking for a priori. I could go back through the report in more detail later and find quotes showing where they explain how they were making these assumptions, assuming I can find them, if you would like.

They account for every factor you list here in detail.

So then is the inch of deformation the extent of what the trusses could do in their models, or am I still missing data?

Well, we know from images that we are looking at up to 55 inches of inward deflection

Possibly, but you don't know what specific mechanism caused it. To be able to say, "this is what caused it," you have to show that what you are suggesting is capable of doing that. That's why I want to see their lab data, not photos of the actual buildings, when we are currently debating the specific mechanisms, per se.

Do they refuse to release it, or have they simply not released it?

The end result is no different, no one else has access to it. And at this point, you're right, who WOULD be to say they wouldn't have tampered with them. That's why the whole issue of not having released the structural information for buildings that didn't even exist anymore and were part of a national disaster frustrates me.

With regards to WTC7, the NIST report concluded that in fact elements of the building's construction were unsafe when subjected to the results of a prolonged fire, they have issued recommendations and they are still being debated as rightly people are arguing that such circumstances are incredibly rare. Nevertheless, WTC7s design was unique, and we're unlikely to see a similar failure for some time, especially considering modern skyscrapers are often built incorporating lessons from it (the new WTC7, the Chinese TVCC).

I have no idea what NIST suggested specifically happened to WTC7, but I know for a fact they don't have all the answers because they came out after their report and admitted it accelerated at free-fall and none of their models predicted that or could explain it, understandably.

[edit on 9-6-2009 by bsbray11]

reply to post by exponent

Be that as it may, FDNY chief officers surveyed 7 WTC and determined that it was in danger of collapse. Chief Frank Cruthers, now the incident commander, and Chief Frank Fellini, the operations commander, both agreed that a collapse zone had to be established. That meant firefighters in the area of the North Tower had to be evacuated. This took some time to accomplish because of terrain, communications, and the fierce determination with which the firefighters were searching. At 5:30 p.m., about 20 minutes after the last firefighters evacuated the collapse zone, 7 WTC collapsed. It was the third steel-frame high-rise in history to collapse from fire -- the other two had collapsed earlier that day. 1

Professional photographer Tom Franklin provides some detail about the timing of the evacuation:
It was about 4 p.m., and they were anticipating Seven World Trade Center collapsing. The firemen were leaving en masse. 5

It was 4:45 p.m., and all the firemen and rescue workers were evacuating Ground Zero after word came that a third building -- WTC 7 -- was ready to fall. 6

www.wtc7.net...

Looks to me the firemen were told to evacuate “late” that afternoon! So where are the photos that they had ALL DAY TO TAKE?

WTC 7 Collapse Foreknowledge
Reports of Foreknowledge of the Collapse of Building 7 in the Oral Histories

911research.wtc7.net...

WTC 7

firefightersfor911truth.org...


Out of all these firefighters testimonies NONE reported a gash in WTC 7.

The photos that you stand behind are a fraud.

9/11 Firefighters: Bombs and
Explosions in the WTC

whatreallyhappened.com...

Firefighters for 9/11 Truth: Not For Firefighters, Not For Truth

conspiraciesrnotus.blogspot.com...


No discussion of gapping gash in WTC7. Are all these firefighter’s liars?

Funny you should claim I am insulting you when you in the same sentence call me a disinformation agent.

Sorry I thought I was sticking to the facts.

mine was not.

Neither was mine.

Originally posted by Gorman91
Also, the building would probably be leaning a bit considering the fire was strongest only in one area.

Damage to WTC 7 was mainly in the SW corner. The fires travelled across the floors, some clockwise, some counterclockwise, depending on the floor number.

At which point were the fires allegedly strongest?

[edit on 9-6-2009 by tezzajw]

Originally posted by nyarlathotep
I have a serious question: If you wanted to bring down WTC7 and make it look like an accident, why then would the tower fall that way? I mean, why wouldn't you make the charges/thermite take out the left side first, then the right side so it would topple over instead of coming straight down? Why on earth would "they" make it look like a controlled demolition when they would want it to appear just as the official story?

1. Demolition of WTC 7 makes the demolitions of WTC 1 & 2 seem feasible.

2. If you're going to tell a lie, you better make it BIG.

3. When you have unlimited resources and the ability to alter societies ostensible reality by means of the media and disinformation agents (like the ones present in this thread) . . . you don't really give a $#!^.

and last but not least . . .

4. Most people want to remain ignorant because for them, reality is too difficult to bear . . .


[edit on 6/9/2009 by JPhish]

Originally posted by bsbray11
That depends on how much reproducible data the analysis is based on.

Excellent.

It was included in the NIST report

It was? Similar calculations were done but without checking thoroughly this seems like an ancillary paper produced by a single person?

and I think given the fact that they had to change certain parameters in their fire simulations to get certain results, we might have another idea as to why they didn't get a consistent result in this particular simulation. Is that not also a reasonable opinion? If they have inconsistent results between two similar cases, that were both reasonable as far as they could tell, then I think that goes to show how fine the lines are that their theories walk.

Potentially, potentially not! As you saw there was very little effort carried out in that paper to determine the cause of, and nature of the differences, simply speculation that material properties may have contributed. NISTs analysis was somewhat more in depth.

Jim Hoffman laid out all the changes they made in their cases favorable to structural failure here:

Don't ever believe anything you read like this. For example, the quote he uses ("aircraft-damaged structural components were removed") is taken soley from NCSTAR 1 which is a summary report to summarise all existing summary reports. He does not actually quote it from the relevant report which elaborates on it substantially. It is literally just speculation, he read through the most summarised of the reports (300 pages to summarise 10,000) and decided that that's what NIST were doing without checking anything.

I haven't verified each one of these personally yet but I already knew that they changed Flight 175's impact angle to maximize damage to the core in their models, and that they had to play around with their fire simulations until they finally got the results they were looking for a priori. I could go back through the report in more detail later and find quotes showing where they explain how they were making these assumptions, assuming I can find them, if you would like.

I know which ones you are talking about, but they did not just decide they needed to make flight 175's impact angle worst, what they did was conduct a study of the information.

From this study they determined the values for speed, impact angle, impact location, material strength etc, all the parameters listed there. But they also determined that there were error margins. The three scenarios (less severe, baseline, more severe) are used to account for these error margins. It's true that only the more severe analysis produced results consistent with 911, but this should not be a surprise or unacceptable.

So then is the inch of deformation the extent of what the trusses could do in their models, or am I still missing data?

Still missing lots of data. The inch of deformation occurs (as far as I can tell) with a single floor restrained model without any heating applied to the perimeter column. Further down in the report (1-6D this is) they conduct a global analysis which includes these effects, indeed I referenced you to pages 36 and 37 of NCSTAR 1-6D. 37 is an important page as it lists why the full floor models could not accurately predict the inward deformation, and then sets out the procedure to do so.

Well, we know from images that we are looking at up to 55 inches of inward deflection

Possibly, but you don't know what specific mechanism caused it. To be able to say, "this is what caused it," you have to show that what you are suggesting is capable of doing that. That's why I want to see their lab data, not photos of the actual buildings, when we are currently debating the specific mechanisms, per se.

You need to read through the entirety of NCSTAR 1-6D really, by the end of the report they have confirmed that this mechanism is capable of inducing large (40 inch plus) deformations to the exterior walls.

The end result is no different, no one else has access to it. And at this point, you're right, who WOULD be to say they wouldn't have tampered with them. That's why the whole issue of not having released the structural information for buildings that didn't even exist anymore and were part of a national disaster frustrates me.

Reasonable comment, I don't disagree. I care little for copyright and patent law, especially when it is used to deny people access to data they would likely not make offensive use of.

I have no idea what NIST suggested specifically happened to WTC7, but I know for a fact they don't have all the answers because they came out after their report and admitted it accelerated at free-fall and none of their models predicted that or could explain it, understandably.

Actually no, after their draft report was released for public comment, they changed it upon request. See their FAQ page here: www.nist.gov... .. Specifically the section "In a video, it appears that WTC 7 is descending in free fall, something that would not occur in the structural collapse that you describe. How can you ignore basic laws of physics?".

I fear I may not have answered your questions thoroughly enough, but i urge you to read at least the entirety of NCSTAR 1-6D before we continue this discussion, as I can keep on pointing you to individual elements of it, but you seem smart enough to be able to understand what they did by yourself, and obviously that would make my life easier

Originally posted by impressme
The photos that you stand behind are a fraud.

No, they are not. You obviously cannot answer the questions I have put to you, and have done your research by only looking at 'truther' websites instead of visiting the source material.

Your motto is "DENY IGNORANCE", you have failed it. I have no interest in continuing a discussion with someone so unable to do any research they think no firefighters commented on exterior damage.

If we can agree that there must have been loads of photos taken on that day, then the fact there is no clear shot of this massive gash suggests to me there was no gash. If there was no gash or for that matter anything else of interest going on with building 7 then why would anybody bother to take pictures of a perfectly normal building when there was so much else going on.

If on the other hand there had been gashes and fires and kinks then i'm sure the photographers would have been waiting all day for the collapse to happen taking photos and videos, plus we should have had numerous high quality video of the building coming down from every conceivable angle since the reporters would have had lots of time to set up their equipment.

Since we do not have any pictures or videos tells me there was nothing happening.

Originally posted by exponent
It was? Similar calculations were done but without checking thoroughly this seems like an ancillary paper produced by a single person?

Regardless of where it was published, it's on the NIST website and was obviously geared toward the WTC study: www.fire.nist.gov...

Potentially, potentially not! As you saw there was very little effort carried out in that paper to determine the cause of, and nature of the differences, simply speculation that material properties may have contributed. NISTs analysis was somewhat more in depth.

Some hostility towards the possibility, eh? The exact same thing happened in two different studies on the same subject. In one case NIST just changed the parameters to get the data they wanted. In the other, they didn't, but I'm sure we would agree they COULD have changed the parameters and still got the result they were looking for. This is called being biased, looking for a certain results, reaching a conclusion a prior, etc., one of the reasons the NIST report was a failure.

Jim Hoffman laid out all the changes they made in their cases favorable to structural failure here:

Don't ever believe anything you read like this.

Look, I just told you I would look through the report myself and find it all myself if you give me time to do so. Are you not satisfied with that? Because I personally trust Jim Hoffman but I don't expect YOU to. My advice to you is don't believe everything NIST says, either. If this WAS an inside job, the federal government would be the last place you would hear it, ok? Which is WHY you shouldn't take everything they say at face value, but actually use your own brain and think about what they are saying they are doing every time they change parameters, assume things that didn't actually happen, etc.

For example, the quote he uses ("aircraft-damaged structural components were removed") is taken soley from NCSTAR 1 which is a summary report to summarise all existing summary reports. He does not actually quote it from the relevant report which elaborates on it substantially. It is literally just speculation

Who is speculating? It sounds to me like you don't know that he is wrong, and without checking yourself, you are just assuming he is. At least HE quoted the NIST report to support his claim, no matter if it came from a summary or not, they still said it, so one would assume they did what they said. You don't even dispute that they did this, apparently, I guess because it wouldn't surprise you if they did. You know all this stuff makes their data unrealistic, right? By definition, since it didn't actually happen that way?

It's true that only the more severe analysis produced results consistent with 911, but this should not be a surprise or unacceptable.

What it IS is unsupported by data, especially all the things that never actually happened, that they had to change. I have no doubts you could get the results you were looking for if you keep playing with the parameters. That's not my point.

Still missing lots of data.

And I guess I'm still waiting on it. Which is fair enough, because I'm dreading digging through the report to find everything Hoffman was talking about.

The inch of deformation occurs (as far as I can tell) with a single floor restrained model without any heating applied to the perimeter column. Further down in the report (1-6D this is) they conduct a global analysis which includes these effects, indeed I referenced you to pages 36 and 37 of NCSTAR 1-6D. 37 is an important page as it lists why the full floor models could not accurately predict the inward deformation, and then sets out the procedure to do so.

I should mention I don't like run-arounds either. I already think this report is pure trash and a whitewash, so having all this trouble finding the right data to cite isn't impressing me much. So far all I have seen is they have shown a whole inch of deformation from a sagging truss. I haven't seen the evidence of great heating of the perimeter columns, either.

You need to read through the entirety of NCSTAR 1-6D really, by the end of the report they have confirmed that this mechanism is capable of inducing large (40 inch plus) deformations to the exterior walls

Great! That's what I'm talking about. Now how do they prove that, is it reproducible, where is the data, etc. That's the next logical step here.

Actually no, after their draft report was released for public comment, they changed it upon request. See their FAQ page here: www.nist.gov...

They still admit it accelerated at the rate of gravity during "stage 2": " Stage 2 (1.75 to 4.0 seconds): gravitational acceleration (free fall)." I have also seen video of Shyam Sunder is person, saying he cannot account or explain that period of free-fall, or ANY period of free-fall, which should be obvious to anyone who has had physics and remembers about energy transfer, energy loss, all those sorts of things. No PE being lost means the building is not doing the work. Even when it wasn't falling at free-fall, it was really, really close. This is one thing for which you will never be able to convince me otherwise, because NIST and everyone who agrees with them is simply wrong. I just stated why, and it's an obvious and very simple proof, but it will take years for people to come out of denial about it, so I'll just wait for that

[edit on 9-6-2009 by bsbray11]