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Originally posted by Muaddib
wcip.....didn't the planes exploded in the twin towers when they crashed against them?.... Didn't those "explosions" send debris, burning debris and burning fuel into wtc7 and other buildings?..... YES THEY DID....
how about, I don't give a crap whether you like me or not, and you should be staying on topic instead of trying to pick fights....
Originally posted by billybob
i said a ROUGH analogy.
the boat does not represent the skyscaper. the boat represents the space in which the force of moving masses is contained. if you would understand it better, imagine that the boat is on top of a spout of water(the spout of water would be the tower) which is descending back down(like in cartoon whale depictions, you know?).
Originally posted by billybob
and, wecomeinpeace, i'll take you up on tower seven. it was clearly imploded by team of crack professionals from the nwo shadow government.
what's also clear, is that it was used as a command center for the demolition of towers one and two.
Originally posted by Attero Auctorita
Originally posted by Simcity4Rushour
What I want to know is why is it so important to so manny people to have there goverments be the Bad guy?
It is important to so many people to know if their government is the "bad guy" and is corrupt because it is counter to democracy and counter to what it means to live in America. - Attero
Originally posted by billybob
the famous murals at the denver international airport perfectly illustrate the whole plan.
Originally posted by Darkmind
Look at Pearl Harbour (and let's not derail this thread here, I'm just using it as an example) where the US intelligence services and government failed to communicate properly. It happens.
Originally posted by XphilesPhan
Unless im mistaken that video isnt one of the WTC buildings so it proves nothing, yes building can be made to collapse with extensive placement of explosives.
yes, the WTC collapsed from an explosive, the explosive impact of an passenger plane.
Originally posted by muzzleflash
could you please present evidence of these claims?
.......................
Please provide links, lest you lose any remaining credibility you may have
Thank You
Originally posted by muzzleflash
OK
How can you say this man is Not Qualified to have a legitimate opinion on this subject
Originally posted by muzzleflash
THEN you state "I am not the ultimate expert..."
Yet For Some reason you dive right into spouting off the same type of pseudo-facts *without the presence of reasonable evidence to support your case* of which you were criticizing in the first place
Originally posted by muzzleflash
Are you a Qualified Structural Engineer for High Rise Buildings or Not?
If so, May we see your credentials?
Originally posted by muzzleflash
I have a feeling you are not a qualified Structural engineer either; because you do not present your case in a professional manner
Originally posted by muzzleflash
So, my question is; Isnt it a bit hypocritical to bash a physicist for not being qualified enough to make a judgement; then you admit you are not qualified enough either; But...You act like you know the absolute truth
Originally posted by muzzleflash
In the case of 911, there is NO truth !
The govt isnt showing us any of the evidence!
Originally posted by muzzleflash
So basically you have made as big a fool of yourself; as you claim the physicist made of himself, due to the fact you potentially did the exact same thing as the person you are criticizing
Originally posted by muzzleflash
Since Neither you or the professor are qualified in making professional assessments of the situation under discussion; I think the only choice i have to get any reasonable opinion is to review the assessments of professionals; and there is a huge lack of professionals who are willing to get involved in this case; for obvious reasons.
INTRODUCTION
The collapse of the World Trade Center (WTC) towers on September 11, 2001, was as sudden as it was dramatic; the complete destruction of such massive buildings shocked nearly everyone. Immediately afterward and even today, there is widespread speculation that the buildings were structurally deficient, that the steel columns melted, or that the fire suppression equipment failed to operate. In order to separate the fact from the fiction, we have attempted to quantify various details of the collapse.
The major events include the following:
The airplane impact with damage to the columns.
The ensuing fire with loss of steel strength and distortion (Figure 1).
The collapse, which generally occurred inward without significant tipping (Figure 2).
Each will be discussed separately, but initially it is useful to review the overall design of the towers.
..................
The towers were designed and built in the mid-1960s through the early 1970s. They represented a new approach to skyscrapers in that they were to be very lightweight and involved modular construction methods in order to accelerate the schedule and to reduce the costs.
...............
THE AIRLINE IMPACT
The early news reports noted how well the towers withstood the initial impact of the aircraft; however, when one recognizes that the buildings had more than 1,000 times the mass of the aircraft and had been designed to resist steady wind loads of 30 times the weight of the aircraft, this ability to withstand the initial impact is hardly surprising. Furthermore, since there was no significant wind on September 11, the outer perimeter columns were only stressed before the impact to around 1/3 of their 200 MPa design allowable.
The only individual metal component of the aircraft that is comparable in strength to the box perimeter columns of the WTC is the keel beam at the bottom of the aircraft fuselage. While the aircraft impact undoubtedly destroyed several columns in the WTC perimeter wall, the number of columns lost on the initial impact was not large and the loads were shifted to remaining columns in this highly redundant structure. Of equal or even greater significance during this initial impact was the explosion when 90,000 L gallons of jet fuel, comprising nearly 1/3 of the aircraft’s weight, ignited. The ensuing fire was clearly the principal cause of the collapse.
......................
The fire is the most misunderstood part of the WTC collapse. Even today, the media report (and many scientists believe) that the steel melted. It is argued that the jet fuel burns very hot, especially with so much fuel present. This is not true.
Part of the problem is that people (including engineers) often confuse temperature and heat. While they are related, they are not the same. Thermodynamically, the heat contained in a material is related to the temperature through the heat capacity and the density (or mass). Temperature is defined as an intensive property, meaning that it does not vary with the quantity of material, while the heat is an extensive property, which does vary with the amount of material. One way to distinguish the two is to note that if a second log is added to the fireplace, the temperature does not double; it stays roughly the same, but the size of the fire or the length of time the fire burns, or a combination of the two, doubles. Thus, the fact that there were 90,000 L of jet fuel on a few floors of the WTC does not mean that this was an unusually hot fire. The temperature of the fire at the WTC was not unusual, and it was most definitely not capable of melting steel.
..................
It is known that structural steel begins to soften around 425°C and loses about half of its strength at 650°C.4 This is why steel is stress relieved in this temperature range. But even a 50% loss of strength is still insufficient, by itself, to explain the WTC collapse. It was noted above that the wind load controlled the design allowables. The WTC, on this low-wind day, was likely not stressed more than a third of the design allowable, which is roughly one-fifth of the yield strength of the steel. Even with its strength halved, the steel could still support two to three times the stresses imposed by a 650°C fire.
The additional problem was distortion of the steel in the fire. The temperature of the fire was not uniform everywhere, and the temperature on the outside of the box columns was clearly lower than on the side facing the fire. The temperature along the 18 m long joists was certainly not uniform. Given the thermal expansion of steel, a 150°C temperature difference from one location to another will produce yield-level residual stresses. This produced distortions in the slender structural steel, which resulted in buckling failures. Thus, the failure of the steel was due to two factors: loss of strength due to the temperature of the fire, and loss of structural integrity due to distortion of the steel from the non-uniform temperatures in the fire.
A basic engineering assessment of the design of the World Trade Center dispels many of the myths about its collapse. First, the perimeter tube design of the towers protected them from failing upon impact. The outer columns were engineered to stiffen the towers in heavy wind, and they protected the inner core, which held the gravity load. Removal of some of the outer columns alone could not bring the building down. Furthermore, because of the stiffness of the perimeter design, it was impossible for the aircraft impact to topple the building.
However, the building was not able to withstand the intense heat of the jet fuel fire. While it was impossible for the fuel-rich, diffuse-flame fire to burn at a temperature high enough to melt the steel, its quick ignition and intense heat caused the steel to lose at least half its strength and to deform, causing buckling or crippling. This weakening and deformation caused a few floors to fall, while the weight of the stories above them crushed the floors below, initiating a domino collapse.
References
1. Presentation on WTC Collapse, Civil Engineering Department, MIT, Cambridge, MA (October 3, 2001).
2. D. Drysdale, An Introduction to Fire Dynamics (New York: Wiley Interscience, 1985), pp. 134–140.
3. A.E. Cote, ed., Fire Protection Handbook 17th Edition (Quincy, MA: National Fire Protection Association, 1992), pp. 10–67.
4. A.E. Cote, ed., Fire Protection Handbook 17th Edition (Quincy, MA: National Fire Protection Association, 1992), pp. 6-62 to 6-70.
5. Steven Ashley, “When the Twin Towers Fell,” Scientific American Online (October 9, 2001); www.sciam.com/explorations/2001/100901wtc/
6. Zdenek P. Bazant and Yong Zhou, “Why Did the World Trade Center Collapse?—Simple Analysis,” J. Engineering Mechanics ASCE, (September 28, 2001), also www.tam.uiuc.edu/news/200109wtc/
7. Timothy Wilkinson, “World Trade Centre–New York—Some Engineering Aspects” (October 25, 2001), Univ. Sydney, Department of Civil Engineering; www.civil.usyd.edu.au/wtc.htm.
8. G. Charles Clifton, “Collapse of the World Trade Centers,” CAD Headlines, tenlinks.com (October 8, 2001); www.tenlinks.com/NEWS/special/wtc/clifton/p1.htm.
Thomas W. Eagar, the Thomas Lord Professor of Materials Engineering and Engineering Systems, and Christopher Musso, graduate research student, are at the Massachusetts Institute of Technology.
Originally posted by muzzleflash
If you claim to be a certified Structural Engineer specializing in High Rise Buildings; you will be givin no credit until you present your credentials as Evidence to back up your claims.
That means we need to know where u went to school so that we may verify that you indeed did receive a degree in this profession.
Originally posted by muzzleflash
I believe you need to be put on the spot here; because you are suggesting that more than half of the population on this forum are "idiots".
Originally posted by muzzleflash
This is easy lol.
Muaddib "In case you haven't noticed skyscrappers are not trees..."
Muaddib "It would be like building a small scale skyscrapper from dominoe pieces. "
Ok so your professional structural engineering analysis is that Skyscrappers are Not trees; but they are more like Dominoes?
This weakening and deformation caused a few floors to fall, while the weight of the stories above them crushed the floors below, initiating a domino collapse.
Originally posted by muzzleflash
LoL This is becoming very funny actually....
"If you hit it at it's top, or center, you will see that the pieces will fall pretty much straight down."
No one was argueing about which direction gravity pulls; but i have a feeling you think the arguement may be about that.
Originally posted by muzzleflash
I apoligize for having to come after you; but you have no mercy on any posters in this forum of whom you disagree with; so why should i take any mercy when i tear your words apart and use them agianst you?
Originally posted by muzzleflash
If you wanna keep treating concerned citizens like "idiots" than I will prove you to be the idiot. Thank you.
Originally posted by muzzleflash
Dont forget; we are waiting to see your credentials, since you obviously claim to be more qualified than the physicist.
Lets see em.
Originally posted by muzzleflash
This is on Topic; i believe; because the poster claimed to have a better education than the Physics professor in reguards to the "physics behind structural engineering"
Originally posted by muzzleflash
I am not taking sides; I do not agree with the physics professor nor do i agree with anyone else. I am Undecided. I have gone back and forth enough to realize we need the Govt to release their information before we can make accurate assessments of this particular situation.
But if someone "claims" to be more formally educated in the specifics of a particular field of science; I would like to see evidence of that.
Im not asking very much; because if the particular poster is indeed a certified structural engineer i will heed their professional opinion.
I just want to get to the bottom of this.
Thank You.
Originally posted by NEOAMADEUS
.....................
then this may explain (?) why all the files on all those Five Laughing & High Fiving Israeli Mossad Agents With their Colour Video Cameras Running from Across the River pointed at the Twin Towers (who were skirted away to Tel Aviv within a few weeks of 9-11) are now CLASSIFIED documents marked TOP SECRET status....?
From the former two categories, the building housed Salomon Smith Barney, American Express Bank International, Standard Chartered Bank, Provident Financial Management, ITT Hartford Insurance Group, First State Management Group, Inc., Federal Home Loan Bank, and NAIC Securities.
The government agencies housed at 7 World Trade Center were the United States Secret Service, the Department of Defense, the Immigration and Naturalization Service, the U.S. Securities and Exchange Commission ("SEC"), the Mayor's Office of Emergency Management, the Internal Revenue Service Regional Council ("IRS"), and the Central Intelligence Agency ("CIA").
en.wikipedia.org...
Originally posted by billybob
civil engineer? LOL. "physics professor"? your credibility just went molten and can now be located in the sublevels.
he is a physics professor, so quotes will no longer be needed.
Originally posted by billybob
however, the world of information is not a honeycomb. it is a fluid. one discipline bleeds into another. salient causes are sometimes found in unexpected places.
like spock, i like logic.
Originally posted by billybob
i like fuzzy logic even better.
Originally posted by billybob
he said in the paper(which none of the attackers ever seem to read, lol), that he was not privy to all the data.