Reconstruction of the Fires in the World Trade Center Towers (Draft)

[LARED]

http://wtc.nist.gov/pubs/NISTNCSTAR1-5Draft.pdf

Warning this is a 60 meg download

For those interested in knowing the characteristics and behavior of the fires in the WTC buildings, this extensive report cover all concerns. It is an extremely well done report that puts to bed any notion that the fires were not capable of negatively impacting the steel structures.

It also states that if not for the damage to the towers, the fires would not have likely caused a collapse.

[spooked911]

1. I downloaded that big boy... someone is going through a lot of effort to

explain the official story...

But I don't think many serious people say that the fires didn't affect the steel at all.

The question is: how did the fires damage the steel core beams in the floors below where the worst fires were, such that these huge core steel beams gave way evenly and rapidly during the collapse? No one who supports the official story has YET explained this.

[petgoat]

2. how did the fires damage the steel core beams in the floors below

This is exactly the question NIST's computer models don't address.
They only modeled above the 77th floor and they stopped the
model at the time of initiation of collapse.

(see p. 29 of the .pdf)

http://wtc.nist.gov/pubs/NCSTAR1-6ExecutiveSummary.pdf

One suspects they didn't like what the model showed about near-freefall
progressive collapse.

[spooked911]

3. yep

I don't even think I've heard try to LARED explain this

[LARED]

5. For goodness' sake, will you stop with the near free fall myth

The actual time it took the towers to fall was somewhere around 14 seconds. That at a minimum is 50 percent more that a free fall of 9.2 seconds. For the record that does not qualify a "near."

[LARED]

4. You're making a lot of assumptions

how did the fires damage the steel core beams in the floors below where the worst fires were, such that these huge core steel beams gave way evenly and rapidly during the collapse? No one who supports the official story has YET explained this.

Why would you assume the fires damaged the steel the core beams below the fires?

What makes you assume the core beams so huge they could stand up to multiple floors impacting them. I assume you are not referring to columns?

And what makes you think the uniformity or speed of the core beams failing has any meaning?

Can I assume your concern is that the investigation has not determined why there was a global collapse once the structure above the impact zones failed?

The NIST report puts it nicely

The change in potential energy due to the downward movement of the building mass above the buckled columns exceeded the strain energy that could be absorbed by the structure.

That is a fancy way of saying when tons and tons of stuff impacts from above, the stuff below is going to break. I am pretty sure if that's what the CT crowd is waiting for the investigation to address, you all will have a long time to wait, as it is unlikely in my opinion that anyone is going to waste money on investigating the obvious. Really, there is no big secrets here, no one that understands how the WTC was constructed is surprised that when the mass of the tower started moving down the structure below it globally collapsed.

[pox americana]

6. "above the buckled columns"

What evidence is there of buckled columns, either on the collision floors or the floors below?

[petgoat]

7. buckled columns

NIST says they have pictures of the building showing buckled exterior columns.

But why did we never see these before?

[pox americana]

9. Are they online?

I haven't seen any buckled columns.

[LARED]

8. Re

When 30 or so floors of building start to tilt, I'm pretty sure some columns buckled.

[pox americana]

10. Nice pic, but I don't see any buckled columns.

And if there were no buckled columns, there was no progressive collapse.

[hack89]

11. You confuse me..

what precisely do you mean by progressive collapse? Is it what we are seeing in Lared's picture or what happened after to the lower floors?

[pox americana]

12. Good question.

But spinning for BushCo is not my job, so you'll have to figure it out yourself. Sorry about that.

[hack89]

30. Isn't easier to say "I don't know"?

instead of descending to grade school put downs? I really respect your intellect now and will surely hang on every word you say from now on.

[pox americana]

34. That would be a lie, because I do know,

and I imagine you do too, that "progressive collapse" is an utterly implausible fiction devised to cover up an utterly depraved crime.

[pox americana]

23. Here's a clue: there's no physcial evidence of it,

it defies the laws of physics, and the NIST just wrote a 10,000-page report unsuccessfully trying to sell it.

So you tell me what it is.

[hack89]

32. Given the choice, I'll go with the report..

seeing how you just gave me line of gibberish.

[LARED]

14. Well that's true

I was counting on your ability to use your imagination. You certainly have an active one.

Inside the building there are 47 columns minus the ones damaged by the jet. If the building is tilting over the columns have buckled.

[pox americana]

35. So 80 floors supposedly buckled in sequence,

one after the other, like a house of cards. That's 22,960 buckled columns, and you can't even produce ONE?

You really think anybody is going to believe this pantload?

[spooked911]

15. The lower core structure held the upper structure before didn't it?

how does the weight of ten or thirty floors going down ten feet suddenly make the weight of the upper floors unbearable for the lower core structure? Is it really so obvious that the lower part of the building would rapidly disintegrate from the weight of the upper floors moving down?

What caused the systematic and global collapse of the core?

Is there a way to mathematically prove how quickly the lower part of the building would break up as the weight of the upper building bore down on it?

[LARED]

16. Static load verses dynamic load

how does the weight of ten or thirty floors going down ten feet suddenly make the weight of the upper floors unbearable for the lower core structure?

The WTC structure was designed for static loads (not quite accurate if you consider wind loads) not dynamic loading from shock or impacts. The supported mass does not change but the energy of that mass changes significantly when it starts to move (dynamic). It is probably a good guess that at a minimum 15 floors impacted the noncompromised structure of the tower. I'm not going to do the math but those 15 floors falling 15 or so feet is a huge amount of energy for the structure to absorb. The structure in order not to fail must elastically absorb the energy (as strain) without failing. When the mass did hit, steel beams bent, column buckled and connections sheared or were pulled apart.

What caused the systematic and global collapse of the core?

Systematic? What do you mean?

Is there a way to mathematically prove how quickly the lower part of the building would break up as the weight of the upper building bore down on it?

Unlikely in my view. It is far to complex a problem to prove. I have done simple energy comparison based on 30% to 50% of the energy of the tower being converted into work energy (ie busted it up) and you wind up with fall time of 12 to 14 seconds. Very close to the actual time.

[spooked911]

18. The structure must have been engineered for redundancy and it is claimed

that the structure could hold 600% of the weight that it was supposed to hold. Would the upper structure falling ten feet, at least intially, completely overwhelm the load-bearing capacity of the lower tower structure?

I have done simple energy comparison based on 30% to 50% of the energy of the tower being converted into work energy (ie busted it up) and you wind up with fall time of 12 to 14 seconds. Very close to the actual time.

Could you go into more detail on how you did this? Thanks.

[spooked911]

66. I'm still waiting to see those calculations. I'd love to see them.

[spooked911]

84. Still waiting.

[janedoe]

19. What weight of the upper building?

The upper part of the building was turning to dust. So, the weight on the lower members was decreasing.

For a true progressive collapse, the floors need to stay intact. Example: a concrete parking garage collapse as the resulting of an earthquake. Also, to have progressive collapse, each floor must fail as a unit. i.e. All supports on a given floor must fail at the same time. This was not the case with WTC 2, as is seen in one of the videos. Otherwise, that rotating top would not have stopped rotating. Also, how does "progressive collapse" explain why that top block dissolved? Is there a progressive collapse that progressis upward?

[LARED]

22. Is that your opinion as

a structural engineer and materials expert?

That the upper structure was turning to dust so it was getting lighter. :rofl:

Your kidding, Right? Right? Please tell me your kidding.

[janedoe]

24. Shut mouth. Open eyes. Observe.

In a "progressive collapse," how can there be a collapse on the right side that is 10-15 floors below the collapse on the left side and have the building fall straight down?

It's a simple mechanics problem. Perhaps you would like to enlighten us with your new theory of physics.

[LARED]

25. What does a picture of venting have to do with the upper section

turning to dust?

[janedoe]

27. You forgot step number one.

Please refer to my post for further instructions. Here is a link to help direct you.

http://www.democraticunderground.com/discuss/duboard.php?az=show_mesg&forum=125&topic_id=49366&mesg_id=49530

[LARED]

29. Thanks for the help

Next time I'm looking for an incoherent post, I'll know where to look.

[spooked911]

38. I think her point was fairly coherent-- the collapse in those stills was

not proceeding floor by floor but half of it was several stories below the rest of the collapse point. How could this happen and have the tower still fall straight down?

[petgoat]

44. half of it was several stories below the rest

It appears to me that NIST has rejected Eagar's "zipper theory". I'm
not clear on whether they retain the pancake theory. I'm skeptical of
the proposition that the collapse of part of a floor would have
sufficient force to bring down the floor it falls on.

Obviously four or five partial floors falling together could punch
through, but how do you get the collapse started?

[LARED]

13. Interesting contrast in perception

I look at the report and think, wow these guys are really doing a great job analyzing the fire's impact on the structure. It really puts any question about the fire temperature or progress to bed.

And you view it as a lot of make work to keep the official story consistent. Do you really think hundreds of professionals from many vocations are just being kept busy to make it look good? That they already know the final conclusion and are just playing along?

[spooked911]

17. I don't know-- maybe like you they really just don't want to believe

that it is possible. Thus, they work and work trying to support the official theory-- if you were paid to do it (assuming you aren't being paid now to support the official story, wink, wink), wouldn't you also work to put out this kind of report?

Here's a question for you-- if one of the "professionals" working on this project thought there was evidence of explosives, do you think they would be able to put it in the report? Or do you think it is impossible such great "professionals" would ever reach such a conclusion?

[LARED]

20. maybe like me, they just don't want to believe???

Wow.

Sure, maybe my 25 years as an engineer has been overridden by my desire to see a President whom I dislike get away with murdering 3000 American citizens. :sarcasm:

Sure, maybe. I have a bridge for sale too.

[spooked911]

41. Will you at least grant it is POSSIBLE that explosives were used to bring

down the towers? As a scientist, it seems you should be open to all possible explanations and not simply rule out explosives because of some (unclear) bias against it.

How can you possibly completely rule out that explosives in the towers assisted their collapse?

[LARED]

53. Shoot, just about anything is possible

Miss Universe knocking on my door in one minute and asking me to marry her is also possible, but highly improbable.

The same goes for explosives in the WTC.

There is no evidence of explosives, and no reason to believe they were needed.

[spooked911]

56. okay, we're making progress

so if it is possible, as you admit, how can you absolutely rule it out, aa you do?

[LARED]

59. The same way I rule out

Miss Universe knocking on my door in one minute and asking me to marry her.

But if you think it's possible I'll straighten my tie just in case.

[spooked911]

64. Not a good comparison though

there is presumably no existing connection between you and miss universe while there are abundant reasons to think explosives were used to bring down the towers. In the case of miss universe, that would obviously be highly unlikely for her to pick you where as controlled demolitions are used ALL THE TIME TO BRING DOWN BUILDINGS.

I assume, as you are a smart person, you can see the difference.

[LARED]

69. I can see the difference but

I can't see any reasons to think explosives were used to bring down the towers.

[spooked911]

74. Really? You can't think of ANY reasons?

Not the fact that the tower collapsed very rapidly and essentially in it's footprint? Not the fact that people witnessed explosions? Not the fact that the NYFD has embargoed firemen from talking about bombs in the WTC? Not the rapid recycling of steel after the collapses? Not the fact that the towers were bombed previously in '93? Not the fact that there was molten steel at the base of the rubble?

You can't think of ANY reasons?

[petgoat]

76. You can't think of ANY reasons?

Add the fact that none of NIST's steel showed evidence of heating
above 250 degrees C.

Another reason the Miss Universe example is a poor one is that there
is no perceived benefit to Miss U from performing her unlikely action.

If the demolition thesis is correct, the perpetrators (if any) turned
a couple of plane crashes into an image as iconic and archetypal as
the mushroom cloud--an image that will remain in world culture for a
thousand years.

It would benefit al Qaeda by magnifying the death and destruction in
their achievement (though why they didn't wait 'til 10:00 when the
towers were full, and strike lower down to trap more people above the
fires I'll never understand.)

It would benefit the Bushcists by creating the "tremendous
opportunity" referenced by Rummy, W, and Condi to remake the world and
justify increased military budgets and invasions and antiterrorist
security measures.

[LARED]

81. Reasons

Add the fact that none of NIST's steel showed evidence of heating above 250 degrees C.

I think you need to read the report I linked before taking that fact to the bank

If the demolition thesis is correct, the perpetrators (if any) turned a couple of plane crashes into an image as iconic and archetypal as the mushroom cloud--an image that will remain in world culture for a thousand years.

That may be an outcome of the collapse, but it is an extremely weak argument that the towers were a controlled demolition. The plane crashes alone are pretty powerful images. It's hard to believe that a highly complex operation like a controlled demolition was included in the plot just to make the images more powerful.

It would benefit al Qaeda by magnifying the death and destruction in their achievement (though why they didn't wait 'tail 10:00 when the towers were full, and strike lower down to trap more people above the fires I'll never understand.)

Again this is a weak argument for controlled demolition as part of the plot. Do you really think al Qaeda or its adherents were going to be disappointed if the buildings did not collapse? Again the risks of a highly complex operation like a covert controlled demolition is way to risky for such a small benefit.

It would benefit the Bushcists by creating the "tremendous opportunity" referenced by Rummy, W, and Condi to remake the world and justify increased military budgets and invasions and antiterrorist security measures.

Are you seriously arguing that without the collapse Bush and his maladministration would have felt constrained? That's hard to imagine.

[petgoat]

92. Reasons

NIST says their steel samples showed "limited exposure if any above 250
degrees C."

http://wtc.nist.gov/pubs/NCSTAR1-3ExecutiveSummary.pdf

(see p. 6 of the .pdf)

"It's hard to believe that a highly complex operation like a
controlled demolition was included in the plot just to make the images
more powerful."

What, do you think the point was to kill some innocent people? What
was the point if not to achieve maximum influence?

First off, what's complex about it? The demolitions expert Van Romero
said a small amount of explosives could do the job. I explained how
they could quickly be installed in the elevator shafts by working from
the top of an elevator car and using it as a movable scaffold.

Whether the purpose of the attack was prestige in the Muslim world or
shock and awe in the USA, a collapse was ten times as effective as a
simple plane crash with fires that burned out and killed a few hundred
people.

"Are you seriously arguing that without the collapse Bush and his
maladministration would have felt constrained?"

AbsoLUTEly! Bush's approval rating was 51%. On 9/10 Rummy announced
that the Pentagon could not account for 2.3 TRILLION in expenditures.
The NORC study of the Florida ballots was about to reveal that Gore in
fact got more votes in Florida, and a campaign to recall the Supreme
Court justices was about to begin. Under those circumstances, how was
Bush going to justify the war in Afghanistan that Niaz Naik was told
bout in July? Let alone an invasion of Iraq, which PNAC had demanded
in 1/98 from Clinton?




Rummy: http://www.cbsnews.com/stories/2002/01/29/eveningnews/main325985.shtml

Naik : http://www.cooperativeresearch.org/entity.jsp?entity=niaz_naik

[pox americana]

57. But there's absolutely no physical evidence to support your theory.

None. Not one of the 22,960 buckled columns, not one of the thousands of truss joints that would have had to fail in order to produce the progressive collapse described in the NIST report.

And all the available evidence (photographs etc.) points to explosives.

[LARED]

60. My buddy pox americana

life is about choices. I you want to beleive the tripe you are trying to sell, have fun.

[pox americana]

61. Life is about choices, correct.

And many Americans choose the easy lie over the painful truth every time. They usually watch Fox News and believe what they're seeing, too. Enjoy.

[spooked911]

46. You didn't answer my question---

-- if one of the "professionals" working on this project thought there was evidence of explosives, do you think they would be able to put it in the report?

[LARED]

54. Yes, I do

think it would be investigated. Why do you have professionals in quote? Are you so far into darkweaving that you think the 100's of professional engineers and scientist are government patsy's?

If there were explosives, it could be part of the plot. Why not include it. In the CT view of the world the all knowing, all powerful, WH would spun it as part of the plot. If you took a objective look at the CT position, most seem to believe the WH is just short of deity. Seeing all, knowing all, in complete control of thousands of people simultaneously. Spinning a few explosives would be child's play in the CT'ers Rovewellian world view.

[spooked911]

55. Then why don't they mention the possibility?

It is not so far-fetched.

[LARED]

63. Who said it was not far fetched?

They could have mentioned the possibility that gremlins living in the columns caused the collapse but they would appear to be fools.

This is not much different than saying

They could have mentioned the possibility that explosives planted on the columns caused the collapse but they would appear to be fools.

[spooked911]

65. again not a good comparison

I think you are too smart to really think that is a good comparison.

Explosives are USED ALL THE TIME TO BRING DOWN BUILDINGS, while gremlins don't exist.

Moreover, there is prima facie evidence that explosives were used in the WTC collapses.

[LARED]

67. Ok I admit I'm pretty sure gremlins don't exist

But you never know for sure.

BTW, I'm not a lawyer but I'm ceretain ignorance cannot be used to establish prima facie evidence.

I have to admit using a prima facie agrument is nice spin by the 9/11 darkweavers as it shifts the burden of proof to proving there was no explosives. Nice try.

[spooked911]

75. what exactly do you mean by "darkweavers"? That is a new one to me.

[hack89]

28. But what is stopping foreign professions from commenting?

if it is so obvious to untrained people like you why hasn't a russian or french engineer said something? I understand they have electricity and the internet and everything now.

[spooked911]

47. this is really irrelevant

besides, we have domestic professionals who doubt the official collapse story-- our own Jane Doe for one.

[AZCat]

48. I don't think that counts

Jane Doe has not given any proof that she (or he, for all we know) actually is a practicing professional.

More importantly, even if Jane doe IS a professional engineer, there is a world of difference between posting anonymously on the internet and accepting responsibility for your statements (and risking censure or loss of license) in public. It is easy to question something cavalierly when there is no risk involved, but more difficult when one's professional reputation is on the line.

[petgoat]

50. It is difficult to question the official story

when one's professional reputation is on the line.

That's exactly the point. Nobody wants to stick their necks out. And
the teams put themselves to the task not of answering "What brought
the towers down?" but "How did fire bring the towers down?" just as
the 9/11 Commission's task was not "What happened on 9/11?" but "How
and why did 19 teenagers with boxcutters wreak such havoc?"

That's why I say only an international team can do an impartial inquiry.

It's entirely possible that explosives were used and Bush had nothing
to do with it, but the Republicans are covering up because it's
embarrassing that the WTC's security company, of which Marvin Bush was
a director for eight years, screwed up so bad.

[AZCat]

88. It's not about sticking your neck out...

It's about making statements for which you can be held liable. If the professionals that are working for the NIST make false statements, they are just as accountable to their accrediting organizations (and to the legal system) as any other professional. In my opinion, there aren't any professionals supporting the alternate claims regarding September 11th simply because they are unable to verify the accuracy of those claims. It would be foolish to risk one's reputation backing a dubious theory when the collapse of said theory would harm the associated reputation. Not until credible evidence appears will anyone say anything - even an international team. Even though they might not be as susceptible to the local politics that might interfere with engineers stateside, they would still be responsible for their statements.

[petgoat]

93. " It would be foolish to risk one's reputation backing a dubious theory"

Was the zipper theory not a dubious theory? Does the pancake theory not
depend on the zipper theory?

"Not until credible evidence appears will anyone say anything"

Not say anythig? They drew floor maps of 1000 degree temperatures with
no evidence. And there is no evidence. It was all destroyed at Giuliani's orders.

[janedoe]

51. If all else fails, shoot the messenger.

Better yet, develop a list of talking points:

1. If you don't like the message, shoot the messenger.
2. Avoid the facts
3. Avoid the facts at all cost.
4. If you're having difficulty with that, toss out a distraction or two.
5. Repeat steps 1-5 until you feel better.

My credentials can be validated -- but they don't change the facts. Would you like to discuss the facts?

Or, perhaps we should discuss why the facts scare you so much? I am quite serious. Fear is a normal response to something this tragic -- and it indeed was quite tragic! As much as we all wish it would, killing the messenger won't change the facts.

Would you like to discuss the facts?

[AZCat]

89. How, exactly, have I shot the messenger?

Please - enlighten me.

[spooked911]

62. Have YOU ever put your career on the line by speaking out about

something that was highly taboo?

If not, I don't think you can fairly question Jane Doe's motives nor anyone else who doubts 9/11 anonymously.

[AZCat]

91. I have a number of issues with your post...

Why is it important whether or not I have done as you said?

Why can't I question someone elses motives if I have not done as you said? Does this mean that I can't sit on a jury if I haven't committed the crime that the defendent is accused of?

What does this have to do with my post? Jane Doe was used as example of a domestic professional that questions the events of September 11th - I pointed out that Jane Doe cannot be counted as such, for the reasons I listed.

Jane Doe is free to make statements regarding September 11th and we can judge those statements on their merits, but Jane Doe cannot claim professional expertise (or earn recognition of such) merely by stating so. If Jane Doe wants to express Jane Doe's opinion and have the weight of any associated reputation placed behind Jane Doe's words, then Jane Doe has to publish those opinions under the original name rather than a pseudonym. Otherwise Jane Doe is just another poster among thousands, and must be judged by the content of Jane Doe's words rather than the paper on Jane Doe's wall.

[mikelewis]

21. Do you really think it should be such a huge question that it....

takes hundreds of professionals from many vocations analyzing the fire's impact on the structure? The reason they are devoting so much time and energy to this issue is because they're busy trying to figure out the highly improbable. They have to answer the question of how the building collapsed and they are not allowed to factor in the possibility of explosives.

While anything can be explained if you put enough ink to paper, this should be a simple problem to solve. But it's not a simple problem because for every answer one hundred other questions pop up. These guys have the ability to put this issue to rest with one math problem and they know it. The speed at which the buildings fell will tell you everything you need to know. Each truss, junction and weld has a quantifiable amount of resistance. With thier resources, they could determine that amount of resistance within a reasonable margin of error. If the mass of the building, and they could use the maximum load numbers if they want, if the mass of the building could move through that resistance at that speed, then they're done.

The reason for my disbelief and many others, is the seemingly complete failure of every support structure almost simultaneously. The pancake theory makes no sense, these were not plates welded to a central core, this was an intricate web of support structures designed to keep that building standing under extreme circumstances. That support net comletely gave out and did it at an incredible speed. If the speed of collapse shows that more energy was required to move through that resistance, they have to consider, and so do you, the possibility that there were explosives. This riddle can be solved, definitely not by me but I'm sure this team of hundreds of professionals could make short work of it.

[janedoe]

26. Nicely stated!

Also note that the 911 report is still a draft, and not the final version. They are waiting to see if there are any more gaping holes in their story that someone will point out to them.

It only took the CAIB team 6.5 months to determine what happened to the Space Shuttle Columbia and write their final report.

[hack89]

31. But as a materials engineer..

can't you give us a technical persective - you know, use math or something?

[mikelewis]

40. I am not a materials engineer but I do know that they have...

load bearing equations for floors, thus max ocupancy rates and the like. From this they can determine resistance. I'm sure the NIST has this information and this could easily be figured out. I don't have the variables, they do. They have the time, the mass, the speed and the resistance. If the equation doesn't balance out, there must be another factor that moved that building at that speed. I believe was is an honest question and doesn't deserve a smarmy reply. Why is it so wrong to ask a question about something that appears so odd? Why aren't you writing smarmy replies to the NIST, they're wasting taxpayers dollars on a question that is so obvious to you that you feel the need to waste your sarcasm on me?

[AZCat]

33. If you think it's that simple...

then I suggest you read up on complex systems. They do not always respond in linearly to input. This can prevent us from simulating events with any reliability, even if we fully understand the behavior of all the individual elements of the system. Care must be taken to construct a model that will provide useful information, or else you just get garbage.

[mikelewis]

43. Obviously, it is not simple but I don't have access to a team of experts..

they do. Drafting a 238 page paper on how fire could melt steel requires just as much effort as figuring out how much a floor is supposed to be able to hold. You add up all the floors and that's the total resistance. Each floor has mass and a maximum load, add those together and you have your total mass. You know the force of gravity. You know the speed. If these don't balance out, there's another factor that increased the speed.

[AZCat]

45. If you don't consider yourself an expert...

or have access to a team of experts, I think it's pretty bold to make statements such as "Drafting a 238 page paper on how fire could melt steel requires just as much effort as figuring out how much a floor is supposed to be able to hold."

Your collapse model doesn't seem right to me. Are you expecting the floors to act retain cohesion during collapse and respond to forces as a unit, rather than deforming or separating? Do you have a reason for modeling the building in such a manner that I might not be aware of?

[mikelewis]

58. So you're saying....

Newtons's laws of motion don't apply here? You're saying the floors wouln't act to retain cohesion thus offer resistance? That must be some pretty amazing jet fuel. Not only can it melt steel, it can negate the resistance in a building. The more I hear about this jet fuel the more amazing its becomes.

Just for your information, the floors do act to retain cohesion. If they didn't, you'd fall through them. The building was not a series of plates welded to a steel core and supported by a flimsy outershell. Each floor was a web of concrete and steel, designed to withstand extreme load changes. In order for the entire floor to collapse, you have to overcome the total resistance that floor exerts in it's effort to obey Newton's first law. Once the building begins to collapse, it has to obey Newton's second law of motion which involves the mass of the building and it's acceleration through that resistance. Since the NIST has access to these figures, they should be able to figure out if the building could have exerted enough force to overcome the resistance in that time frame.

[AZCat]

86. I think you miss my point.

It seems you are not allowing part of a floor to collapse prior to the rest. The force applied when I stand on the floor is not comparable to the forces applied during a building collapse. It certainly is possible for the floor to shear under certain loading conditions, and your model doesn't allow for that possibility. Such a failure (of the floor) would change the response of the structure to other forces.

[spooked911]

37. yes, good point. It seems these "professionals" doth protest too much

they are working TOO hard at something that should be so OBVIOUS according to LARED. If the collapse was so simple and easy to explain, why are they putting out huge report after huge report?

[mikelewis]

42. No shit, 238 pages is how many man hours?

How much are they going to spend to prove that something completely improbable is possible? They should spend the time on determining if it's possible to bring that building down with the factors at hand and quit making bullshit supositions. It'd take for ever to figure out how the building came down if there were indeed explosives and they do not factor it in. They'll be grasping at possibilities until the cows come home.

[pauldp]

68. "WE FOUND THE MURDER WEAPONS !!"

A Bloody Knife and a Smoking Gun. And we promptly washed them clean
and shipped them off to China to be melted down. BUT we took a few photos! Here is our 10,000 page analysis of those photos, it explains how the gun went off by itself and the knife fell off a shelf into the victim. Hope you find it convincing.

end:sarcasm:


edit:typo

[petgoat]

77. Murder Weapon Photos

Photos nothing. They have photos of a lead pipe and a candlestick.

All they have is computer models of guns and knives. "But look how
bloody and smokey they would have been if we had them!"

[philb]

36. I can't down load the file; such technical discussion can be useful, but

what about the witnesses who experienced explosions in both buildings-
firefighters, janitors, engineers, survivors, people in buildings next door, etc.

For example:
Explosion at Base of WTC prior to collapse- North Tower
Phillip Morelli, a construction worker, told reporters at a New York television station (NY1 News) that on the morning of 9-11 when the North Tower was struck, he was thrust to the ground by two explosions in the fourth sub-basement. Somewhat later, another explosion (which made the walls explode) once again hurled him to the ground. Morelli then exited that building and went inside the South Tower’s sub-basement, where once again he felt the same type of underground explosions.


Chief Engineer magazine also ran an article in their We Will Never Forget commemorative issue on those who were eyewitnesses to the 9-11 terrorist attacks. One of these men was Stationary Engineer Mike Pecoraro, who worked in the WTCs second sub-basement. After hearing some loud explosions, they ventured to a machine shop and found, much to their amazement, “There was nothing there but rubble. We’re talking about a 50-ton hydraulic press – gone!” Pecoraro then went on to say that “he was convinced a bomb had gone off in the building.” http://69.28.73.17/thornarticles/911bombs.html

Teresa Veliz, a facilities manager who fled from the 47th floor of the North Tower, described the scene as she made it down to street level: “There were explosions going off everywhere. I was convinced that there were bombs planted all over the place and someone was sitting at a control panel pushing detonator buttons.” (Source: September 11: An Oral History by Dean E. Murphy – Doubleday Books, 2002)

Rick Sanchez, who was giving his report live on MSNBC, had this to say, “I spoke with some police officials moments ago, Chris, and they told me they have reason to believe that one of the explosions at the World Trade Center, aside from the one that may have been caused by the impact of the plane with the building, may have been caused by a van that was parked in the building that may have had some type of explosive device in it.”

Firefighters at WTC:
"Tower two has had major explosion and what appears to be a complete collapse", "...those involved in the secondary explosion at tower 1, 'kay, I've got five patients...", "We have got numerous people covered in dust from the secondary explosion...", "We've got another explosion at the tower..."

[philb]

39. South Tower - reports of explosions

South Tower
Fox 5 News, a New York television channel, was able to catch on videotape a large white cloud billowing out near the base of the South Tower. The newsman commented: “There is an explosion at the base of the building….white smoke from the bottom …something has happened at the base of the building… then, another explosion.

note: this smoke was captured in pictures and videos as well and has been previously posted

Another eyewitness, Louie Cacchioli, a 51 year old firefighter assigned to engine 47 in Harlem whose interview appeared in the September 24, 2001 edition of People Magazine had this to say, “We were the first ones in the second tower after the plane struck. I was taking firefighters up in the elevator to the 24th floor to get in position to evacuate workers. On the last trip up a bomb went off.”

• Official: Battalion 3 to dispatch, we've just had another explosion.
• Official: Battalion 3 to dispatch, we've had additional explosion.
• Dispatcher: Received battalion command. Additional explosion.
• <...>
• Dispatcher: Battalion 5, be advised we're trying to contact Battalion 3 at this moment to report north tower just collapsed. http://www.wnbc.com/news/1315651/detail.html

CBS News Channel Eyewitness Describes 'Secondary Explosions' in the WTC The following clips originate from CBS Channel 2 in New York. The reporter is in a helicopter as the WTC Towers collapse. http://prisonplanet.tv/articles/april2004/042704secondaryexplosions.htm

"So they escorted us thru the exit of World Trade 2 and I had just reached the revolving door of the building that I heard a loud explosion and the whole building collapsed. <...> When that explosion took place and the building was crumbling over me I could see the pics of my wife, my parents, grandmother loved ones flash thru my mind and now what a relief that we are alive." http://www.truthorfiction.com/rumors/s/survivor3.htm

[philb]

49. NIST expert says jet fuel likely burned less than 10 minutes.

Dr. Shyam Sunder, Lead Investigator,National Institute of Standards and Technology (NIST): "The jet fuel probably burned out in less than 10 minutes. http://cms.firehouse.com/content/article/article.jsp?sectionId=46&id=25807

[petgoat]

52. NIST says jet fuel burned out in ten minutes

Here it is from the horse's mouth:

http://wtc.nist.gov/media/Public%20Transcript%20021204%20Final1_withlinks.pdf

(see p. 8 of the pdf)

[carlvs]

72. However,

That same paragraph also stated:

"... The jet fuel acted much like a matchstick. It was something that spread throughout the building in those affected floors and caused ignition of the fires. But the jet fuel itself burnt in a matter of minutes, within less than ten minutes. So what burned over the next hour, or hour and a half, was really the contents of the buildings, the everyday contents of the buildings...."

Selective quoting from a document... well, it's just so creationist...:sarcasm:

[petgoat]

78. "Selective quoting"

I considered the lack of the mythic jet-fuel inferno to be the point.

The ignition of the contents of the building takes it out of the mythic
realm so all we have is an ordinary high rise office fire. And steel
framed highrises do not fall from ordinary fires.

You're going to tell me that a desks and file cabinets heated the core?
Was there anything in the core to burn? It was elevator shafts and
bathrooms and HVAC.

[VTMechEngr]

82. Well, a plane punching into the building was bound to drag stuff into

The core. And the core is surrounded by office. You don't think a 5-6 ton Pratt & Whitney PW4056 engine traveling at 733 feet/sec couldn't mow down some measly A36 columns? even with concrete around them? Fire got into the core because people in the lobbies saw flames shoot out of the elevator shafts after the elevators fell.

[petgoat]

94. " people in the lobbies saw flames shoot out of the elevator shafts "

So fuel got in the elevator shaft. You've never seen a carburetor backfire? It doesn't make your engine fall down.

In fact, the presence of the elevator shafts is a major argument against the proposition of major core fires. The fuel fall down the shafts.
It didn't ignite seriously. The firemen walked up the stairwells just
fine.

[VTMechEngr]

70. Wow, who'd a thunk the fuel would burn off and leave a nasty office fire!

[janedoe]

71. Wait, I know what happened.

The jet fuel burned so hot in the jet ...that it melted the jet.

[VTMechEngr]

73. Ooookay

Or, it went all to shreds after tearing apart a third of the buildings structure.

[spooked911]

83. What, does fuel burn indefinetely? Geez, why are oil prices so dang high?

[VTMechEngr]

85. explain your post? Mine was a no duh post.

And yours? Or did you reply to the wrong post?

[spooked911]

87. joke

[VTMechEngr]

90. ah. sorry

Too many "jokes" around here were serious. Hard to deprogram.

[mikelewis]

79. I didn't know there were two video's of the first hit?

I knew about the Naudet Brothers catching the first strike but which is the other one? Any links?

http://wtc.nist.gov/pubs/NISTNCSTAR1-5Draft.pdf
Pages 6
2.2.1 Time Line for the First 30 Seconds

"The data regarding the events immediately following the impact of American Airlines Flight 11 on the north face of WTC 1 at 8:46:30 a.m. came exclusively from two videos and one set of a few still photographs. The two videos were shot from the north and the northwest of WTC 1, respectively. The photographs were shot from the southeast of the tower. These formed the basis for the following time line, estimation of the speed of the approaching aircraft, description of the immediate damage to the tower (strictly as seen from the outside), and characterization of the fire behavior in the immediate aftermath.
Figure 2–1 shows selected frames from the videos."

When you look at the pictures, they're all from the Naudet video. Anyone know of the other?

[mikelewis]

80. Actually, the last two are not from the Naudet Film

They are entitled Copyright 2001 John F. Davis

Has anyone seen this?

[Make7]

96. This is the only other one I recall seeing:

http://www.terrorize.dk/911/wtc1hit2

-Make7

[nomatrix]

95. I don't think cooling has been addressed

when considering the jet fuel fire lasting only 10 mins.

"Manual of Steel Construction from AISC (8th edition, 1980)
From Chapt. 6-5

Effect of Heat on Structural Steel

To judge the effect of fire on structural steel, it is necessary to consider what happens in such an exposure. Peculiarities of this exposure are:
(1) temperature attained by the steel can only be estimated
(2) time of exposure at any given temperature is unknown
(3) heating is uneven
(4) cooling rates vary and can only be estimated, and
(5) the steel is usually under load, and is sometimes restrained from normal expansion.

Carbon and high strength low-alloy steels that show no evidence of gross damage from exposure to high temperatures, or from sudden cooling from high temperatures, can usually be straightened as necessary and be reused without reduction of working stress. Quenched and tempered alloy steels should not be heated to temperatures within 50 degrees F of the tempering temperatures used in heat treatment. Thus, for the quenched and tempered constructional alloy steels approved by the AISC Specification.i.e.,ASTM A514, for which the tempering temperature is 1150 degrees F, the maximum steel temperatures should be 1100 degrees F.
Steel that has been exposed to very high temperatures can be identified by very heavy scale, pitting, and surface erosion. Such temperatures may not only cause a loss of cross section, but may also result in metallurgical changes. Normally these conditions will be accompanied by such severe deformation that the cost and difficulty of straightening such members, as compared to replacement, dictates that they be discarded.
Steel members that have suffered rapid cooling will usually be so severely distorted that straightening for reuse will seldom be considered practicable.
In some cases, there may be some deformation in members who normal thermal expansion is inhibited or prevented by the nature of the construction. Such members may usually be straighted and reused.
Connections require special attention to make sure that the stresses induced by a fire, and by subsequent cooling after the fire, have not sheared or loosed bolts or rivets, or cracked welds."

(Is this the book you were looking for column allowable load in kips, Lithos?)

For the record, I am not an engineer, but have enough construction knowledge to find the resources.

I also will not close the door on appearance of controlled collapse.

I haven't looked at 1993 damage done from the explosives used that could have weakened the supports in lower elevations.

The sounds people heard of explosions can be classified by experiences. For example, some are able to identify what gun is used by the noise of the shot.

How many can identify the sound of a hydraulic burst/explosion from too much weight? It sounds like an explosion.