So you are saying the resulting torque at impact of the falling 15 stories twisted all 95 floors of independently bolted gutters/support columns either all at once or perfectly, one at a time, to result in a near perfect symmetrical descent??Originally Posted by Mick
The only thing guaranteed in life is deception. . . everything else is optional . . . George B
No. I'm saying it's impossible for a building like WTC1,2 or 7 to topple over.
Yes - people look at a building and think it is like a plank of wood - tip over a plank that is sitting on its end and it topples.
but to ge that toppling you need 2 things - it has to topple over far enough so that the centre of gravity is no longer above the original "footprint" of the building on hte ground, AND - and most importantly - it has to stay together as a unitary structure.
But tip over a building and the internal structure gives way usually long before the CoG is outside the footprint. And if the CoG does get outside the footprint then the structural integrity usualy fails shortly after.
And as soon as the structural integrity fails the components stop "toppling" and fall vertically - retaining the initial sideways velocity they have gained from toppling - regardless of where the CoG is.
You can see this happening in some chimney demolitions - especially brick ones - the chimney topples, then the brickwork breaks up and is all collapses. Here's an example - albeit hte view is foreshortened and it doesn't collapse quite as vertically as it seems but it clearly does break up and stop toppling:
Last edited by MikeC; February 3rd, 2013 at 11:22 AM.
"Men never do evil so completely and cheerfully as when they do it from religious conviction." -Pascal
"It is very important not to mistake hemlock for parsley; but not at all so to believe or not in God" - Diderot
That is the first time I have heard that . . . you may be correct . . . but do you have structural engineers, architects, demolition experts testifying to that opinion?
The only thing guaranteed in life is deception. . . everything else is optional . . . George B
I See your chimney and will raise you two . . . chimney poker. . . LoL!!
http://www.youtube.com/watch?v=3FAVG1AaZ98&sns=em
http://www.youtube.com/watch?v=wa2ddHX05Hc&sns=em
Here is an all brick one . . .
http://englishrussia.com/2008/09/23/pipes-collapsed/
Last edited by George B; February 3rd, 2013 at 12:13 PM.
The only thing guaranteed in life is deception. . . everything else is optional . . . George B
Oy, you! Turn that phone OFF for once (feel the love!)! I thought you were off to superbowl, you tart!....watch out for pyramids with thirteen steps.....
No, I certainly wouldn't consider it conclusive proof of anything, as you know.
Enjoy the game! x
Funny we both chose the same quote! ^^^^^ Mick, have a night off, mate!
Of course. But beware of such phrases as 'crush rate' - that could prove misleading in retrospect.
Thanks, we are not actually there yet, just about to pop over.
Hows about conclusive proof of it not being gravity driven collapse?
I am off to a game party . . . have a good evening Lee!!!! You too Mick have some fun!!
Last edited by George B; February 3rd, 2013 at 01:09 PM.
The only thing guaranteed in life is deception. . . everything else is optional . . . George B
Get lost!! you think you own this place, or something? Oh, hang on a sec....
Have a good 'un! x
Note that at least the 2nd one there - the Steetly chimney in Hartpool - was reinforced concrete - so it is not surprising it didn't fall apart.
And indeed it IS possible for buildings to collapse sideways without disintigrating - time frame and construction are the main criteria I think - shorter buildings take less time to fall and so may not have time to break apart, and concrete ones may hold together better for a while than steel ones where the load is all on bolts and welds.
Here's a great example of both aspects combining:
with explainations of how and why here
good shot - you can see the bricks "letting go hands" in a few places.Here is an all brick one . . .
http://englishrussia.com/2008/09/23/pipes-collapsed/
"Men never do evil so completely and cheerfully as when they do it from religious conviction." -Pascal
"It is very important not to mistake hemlock for parsley; but not at all so to believe or not in God" - Diderot
Yes they were and my brother in law is paying the price . They lied and told them all it was safe .
Sorry for your brother in law . . . seems there is other evidence that rescue workers have had increased health problems as compared to the average . . . if so . . . what else have they been wrong about????Yes they were and my brother in law is paying the price . They lied and told them all it was safe .
The only thing guaranteed in life is deception. . . everything else is optional . . . George B
Well he is still alive but barely . Iv never asked him what he saw being he was there at the time of the collapse . and afetrwards at the cleanup . World Trade Center Rescue Workers Believed EPA, Ended Up Sick http://www.ucsusa.org/scientific_int...pollution.html
Rate of fall posts moved to:
http://metabunk.org/threads/1142-WTC...rate-of-crush)
Anyone heard of this theory? I find it very fascinating =)
Interesting they are claiming no greater health risks for first responders and residents. As usual, claims and counter claims... no wonder people are confused and suspicious.
http://articles.latimes.com/2012/dec...-risk-20121218
The overall cancer incidence among rescue and recovery workers was the same as with the controls. But zeroing in on cancers that appeared at least five years after the attacks – given the long latency period for cancer, these cases were more likely to be linked to WTC exposure – the researchers found that rescue and recovery workers were 43% more likely to develop prostate cancer, twice as likely to get thyroid cancer and nearly three times more likely to be diagnosed with multiple myeloma.
When the researchers used additional statistical controls to account for the fact that firefighters were more likely to get annual cancer screenings, the increased rate of thyroid cancer was no longer significant.
You have the right to remain silent but is that really a good idea?
Yes, but many and I think it would be impossible not to have detected radiation and seismic signatures appropriate for such massive underground detonations . . . still fascinating. . . .
Last edited by George B; February 8th, 2013 at 07:02 AM.
The only thing guaranteed in life is deception. . . everything else is optional . . . George B
The vet school at the U of Penn has been doing a health study of the search and rescue dogs that worked the WTC site. Their study did not find any increased health issues with the dogs. The dogs may not have spent as many hours as the first responders did, some were already in middle age, so there wasn't time for them to develop cancer and dogs many respond differently to cancer inducers.
Most of the dogs worked until a normal retirement age. I think that the last one was retired within the last year. At least one of them was killed by a criminal he was chasing
I still find it interesting.
Reposting from other thread as it as it belongs here as well.Aha:
http://www.astaneh.net/#
By: Abolhassan Astaneh-Asl, Ph.D., P.E., (www.astaneh.net) Professor, University of California, Berkeley
One week after the 9/11/2001 tragedy, started reconnaissance and investigation of the collapsed World Trade Center towers in New York supported by the National Science Foundation. Later, in May of 2002, I testified before the Committee on Science of the House of Representatives on my findings and received drawings of the WTC from the Committee to continue my studies of the WTC structure. Since then, I have led a team of more than 11 highly qualified volunteer researchers and engineers and have completed the analyses of the impact of various airplanes on the World Trade Center towers in order to learn lessons from this tragedy that can be used to prevent such catastrophic collapses and to save lives.
Since the 9/11, each year, I have given a Memorial Lecture on the WTC, remembering the victims and first responders who so heroically gave their lives to save others, and then providing an update on engineering aspects of the collapse and reconstruction of the WTC buildings. This year, I am devoting most of the Memorial Lecture to release, for the first time, the results of our five- year studies of the structural aspects of the WTC design and the collapse. Our 5-year analysis primarily focused on finding an answer to the question of: “What would have happened if instead of the unusual and relatively light bearing wall structural system with no framing, used in the WTC towers, a more traditional system of structural framing used in almost any other structure, was used? Very few people are aware of the fact that the WTC towers did not need to follow any design code and did not need to obtain the construction permit from the City. The structural system used in the towers was an unusual system of “Steel Exterior Bearing Walls and Interior Compression Columns” with no framing system in between. There is no record of use of such a system before or after the design and construction of the World Trade Center. The issue of structural design of the WTC and its effects on the fate of these towers on that tragic day has not been studied or reported by other studies of the WTC. The results presented here will show what would have happened if the towers were designed following the code and using the structural systems used in almost any other building structure instead of the unique system used in the collapsed WTC towers
Nothing illegal. But he's criticizing what was done.
Another description of the lecture.
http://www.euken.com/group/seaoc/mai.../msg01241.html
Very few people are aware of the fact that the WTC towers did not need
to follow any design code and did not need to obtain the constructionpermit from the City. The structural system used in the towers was anunusual system of “Steel Exterior Bearing Walls and Interior CompressionColumns” with no framing system in between. During this lecture, thefocus will be on the results of a five- years studies of the structuralaspects of the WTC design and the collapse. The 5-year analysisprimarily focused on finding an answer to the question of: "What wouldhave happened if instead of the unusual and relatively light bearingwall structural system with no framing, used in the WTC towers, a moretraditional and code-based system of structural framing, used in otherstructure, was used?”The results presented here will show that if the towers were designedfollowing the code and using the traditional structural framing systemsused in almost any other building structure, such as moment frames,braced frames, shear walls or tube systems, instead of the unique andunusual system used in the collapsed WTC towers, the terrorist attacksmost likely would have resulted in only local damage and not completeand catastrophic collapse of both towers where 3,000 people who weretrapped in them perished. It must be stated that those 19 murderers whoflew the passenger planes into the WTC Towers and their organizers andbackers are fully and directly responsible for this murderous act.However, by learning from this criminal act, it is hoped that we canprevent these criminals in the future from committing mass-murder usingour structures.
http://s1.zetaboards.com/LooseChange...pic/3873416/1/
Content from external source:
In another interview, with the BBC recorded 2 months after 9/11, Leslie Robertson had this to say; "And then of course with the 707 to the best of my knowledge the fuel load was not considered in the design, and indeed I don't know how it could have been considered. But, and with the 767 the fuel load was enormous compared to that of the 707, it was a fully fuelled airplane compared to the 707 which was a landing aircraft. Just absolutely no comparison between the two."
Well, based on documentation that the NIST obtained in 2003, the Towers most definitely were designed to handle a 600 mph Boeing 707 impact.
In a followup article for the NY Times, published on December 3, 2003, the same reporter, James Glanz, now, in effect retracted his earlier story;
"The investigators also said that newly disclosed Port Authority documents suggested that the towers were designed to withstand the kind of airplane strike that they suffered on Sept. 11.
Earlier statements by Port Authority officials and outside engineers involved in designing the buildings suggested that the designers considered an accidental crash only by slower aircraft, moving at less than 200 miles per hour.
The newly disclosed documents, from the 1960's, show that the Port Authority considered aircraft moving at 600 m.p.h., slightly faster and therefore more destructive than the ones that did hit the towers, Dr. S. Shyam Sunder, who is leading the investigation for the National Institute of Standards and Technology in the Commerce Department said."
The reference to these documents appears in NCSTAR 1-2, 8.2 AIRCRAFT IMPACT DAMAGE ANALYSIS, 8.2.1 Safety of the WTC Towers in Aircraft Collision
"Finding 11 acknowledges that " The documents indicate that a Boeing 707, the largest commercial aircraft at the time, flying at 600 mph was considered and that the analysis indicated that such collision would result in only local damage which could not cause collapse or substantial damage to the building and would not endanger the lives and safety of occupants not in the immediate area of impact. No documentary evidence of the aircraft impact analysis was available to review the criteria and methods used in the analysis of the aircraft impact into the WTC towers, or to provide details on the ability of the WTC towers to withstand such impacts."
Here are a few of the salient points that the NIST found in the discovered Port Authority documents from February 3, 1964:
1. A structural analysis was carried out by the firm of Worthington, Skilling, Helle & Jackson and is the most complete and detailed of any ever made for any building structure. The preliminary calculations alone cover 1,200 pages and involve over 100 detailed drawings.
2. The buildings have been designed for wind loads of 45 lbs per square foot which is 2.5 times the New York City Building Code requirements of 20 lbs per square foot, the design load for the Empire State, Pan American and Chrysler Buildings. In addition to static wind loads, a complete dynamic analysis has been made to take into account extremely high velocity gusts.
3. The buildings have been investigated and found to be safe in an assumed collision with a large jet airliner (Boeing 707 - DC 8) travelling at 600 miles per hour. Analysis indicates that such collision would result in only local damage which could not cause collapse or substantial damage to the building and would not endanger the lives and safety of of occupants not in the immediate area of impact.
7. The design has been reviewed by some of the most knowledgeable people in the construction industry. In a letter to John Skilling, the Structural Engineer for the World Trade Center, the Chief Engineer of the American Bridge Division of U.S. Steel Corporation said:
"In reviewing this design with our Operating and Construction Departments, we are very optimistic that you have turned a new page in the design of structural steel."
You have the right to remain silent but is that really a good idea?
My interpretation of the above post is that despite all the retro analysis and theories as to why the towers came down and all the claims that 'you cannot compare the Empire State crash', 'the towers were only designed to withstand a lighter aircraft only lost in fog and travelling at 200mph with a low fuel cargo and the 'pancake' progressive collapse theories etc... it is all BUNK and DISPROVED.
All these factors were looked at extensively by the highest calibre architects and structural engineers:
1. A structural analysis was carried out by the firm of Worthington, Skilling, Helle & Jackson and is the most complete and detailed of any ever made for any building structure. The preliminary calculations alone cover 1,200 pages and involve over 100 detailed drawingsIt was even calculated that the towers would stand if a local PARTIAL COLLAPSE resulted from an impact such as occurred on 9/11 and naturally the effect of fire weakening and expanding the steel was factored in. As was the dissipation of the heat through the conductive properties of the steel.The buildings have been investigated and found to be safe in an assumed collision with a large jet airliner (Boeing 707 - DC 8) travelling at 600 miles per hour. Analysis indicates that such collision would result in only local damage which could not cause collapse or substantial damage to the building and would not endanger the lives and safety of of occupants not in the immediate area of impact.
"After the bombing of the WTC in 1993, Leslie Robertson, one of the engineers who worked on the towers' structural design in the 1960s, claimed that each had been built to withstand the impact of a fully fueled 707. The 707 was the state-of-the-art airplane, and the Port Authority was quite amenable to considering the effect of an airplane as a design criterion...I don't know if we considered the fire damage that would cause. Anyway, the architect, not the engineer, is the one who specifies the fire system."
"Of course, when Yamaski was designing the buildings he was aware that steel, when it reaches an inherent temperature of 1200 degrees, will stretch at the rate of 9 1/2 inches per 100 feet. He undoubtedly took into account the possibility of a plane's hitting the building and causing the steel to stretch in a resulting fire. There might even be a collapse, but only on the side of the building that was 'hit. Partial collapses often happen in burning buildings."
Last edited by Oxymoron; March 3rd, 2013 at 06:20 AM.
You have the right to remain silent but is that really a good idea?
George B (March 3rd, 2013)
Here are the actual figures. . . .707-320 and 767-200 next
Takeoff weight was increased to 302,000 lb (137,000 kg) initially and to 312,000 lb (142,000 kg) with the higher-rated JT4A's and centre section tanks. First flight was on January 11, 1958; 69 turbojet 707-320s were delivered through January 1963, the first passengers being carried (by Pan Am) in August 1959. No −320 Intercontinental models were re-engined with fan engines in civil use, but around year 2000 the Israeli Air Force re-engined two ex-Sabena −320 based military tankers.
http://en.wikipedia.org/wiki/Boeing_707
767-200
Maximum
takeoff weight 315,000 lb
767-200ER
Maximum
takeoff weight 395,000 lb
http://en.wikipedia.org/wiki/767-200
The only thing guaranteed in life is deception. . . everything else is optional . . . George B
But the buildings DID survive the plane impacts, just as expected.
It was the fire that caused the collapse.
It was designed to survive a plane impact and the resultant fire from fully fueled aircraft.
"Of course, when Yamaski was designing the buildings he was aware that steel, when it reaches an inherent temperature of 1200 degrees, will stretch at the rate of 9 1/2 inches per 100 feet. He undoubtedly took into account the possibility of a plane's hitting the building and causing the steel to stretch in a resulting fire. There might even be a collapse, but only on the side of the building that was 'hit. Partial collapses often happen in burning buildings."
We did not witness a partial collapse or even a series of partial collapses... we witnessed a total collapse at near free fall speed virtually in it's own footprint. This should not have happened.
"After the bombing of the WTC in 1993, Leslie Robertson, one of the engineers who worked on the towers' structural design in the 1960s, claimed that each had been built to withstand the impact of a fully fueled 707.
It was clearly engineered to withstand a partial collapse even. i.e. a massive chunk out of the building and still it should stand...
There might even be a collapse, but only on the side of the building that was 'hit. Partial collapses often happen in burning buildings."
We are not even talking about one fluke... three total collapses in hours...
Are you seriously suggesting that the top people in their field would design and engineer these buildings to withstand a fully fueled jet crash and fail to take into account there may be a fire? I think that would be classified as gross professional negligence and I do not believe they were guilty of that.
Planning to withstand such a crash would encompass the event and the consequences or else it would be pointless to bother engineering against the event.
You have the right to remain silent but is that really a good idea?
Perhaps someone though a fire would only lead to partial collapse, but they were wrong. There WAS a partial collapse in both cases, but partial collapse quickly led to global failure.
Ok, we have moved from, no one envisaged this type of event and the towers were not designed or engineered to cope with it.
To
Yes they were designed to survive an event such as this but they didn't.
You have the right to remain silent but is that really a good idea?
No, they were not designed to withstand this exact event. If they were, then the interior columns would have been encased in concrete. The new WTC is designed to withstand this type of event.
So what is different to the envisaged disaster they were evidentially designed to withstand and the actual disaster which they did not withstand?
According to Jazzy concrete is so weak it could be knocked off with little effort and a sledge hammer, how is encasing the columns in concrete going to help when according to the physic on here the extremely strong aluminium of a plane can slice through the steel core easily?
Last edited by Oxymoron; March 3rd, 2013 at 10:51 AM.
You have the right to remain silent but is that really a good idea?
The "envisaged" disaster was being hit by a 707, which would not have contained the amount of fuel these planes were carrying and would have been traveling slower.
BTW let's clarify this, the holes made by the impact are not 'partial collapses', they are impact damage.
Partial collapse would be a separate and distinct event.
It happened for a few seconds as the top slipped forward but due to the fact the top did not slide off completely before the total collapse ensued, even that would be moot.
You have the right to remain silent but is that really a good idea?
You have just posted debunked, bunk.
Do you not bother reading the posts?
You have the right to remain silent but is that really a good idea?
George B (March 3rd, 2013)
The fireproofing was stripped off many locations by the impact and explosion. So encasing the columns in concrete would have mean they would have withstood the fire for a lot longer. It was one of the recommendations of the NIST report.
I did not mean the impacts were a partial collapse. I was referring to the first few seconds of the collapses when one side fell more than the other. Initially it was a partial collapse, but due to the damaged columns and the widespread fire damage it quickly spread to the entire cross-section of the building.
A 'lot longer than an hour'...before a total collapse at near free fall in virtually own footprint?
So you are saying they did not take fireproofing being dislodged into account during their evaluations even though they "undoubtedly took into account the possibility of a plane's hitting the building and causing the steel to stretch in a resulting fire."
And they also forgot to take into account steel stretching and weakening in WTC 7?
Very remiss and highly unlikely when you consider the massive technical work they put in, bearing in mind "The preliminary calculations alone cover 1,200 pages and involve over 100 detailed drawings" and that being at the top of his game; "when Yamaski was designing the buildings he was aware that steel, when it reaches an inherent temperature of 1200 degrees,will stretch at the rate of 9 1/2 inches per 100 feet".
As stated, all of which amounted to;"the most complete and detailed of any"(evaluation) "ever made for any building structure."
Last edited by Oxymoron; March 3rd, 2013 at 12:46 PM.
You have the right to remain silent but is that really a good idea?
You cannot in any logical way have it that 'the first few seconds' amounted to a partial collapse otherwise it would all have to be categorized as 'a series of partial collapses'.
You have the right to remain silent but is that really a good idea?
A factor of TWELVE if you calculate the energies involved.
I said none of that. You made it up, which is what you do when you can't follow an argument.According to Jazzy concrete is so weak it could be knocked off with little effort and a sledge hammer, how is encasing the columns in concrete going to help when according to the physic on here the extremely strong aluminium of a plane can slice through the steel core easily?
Concrete is BRITTLE. It has very little tensile strength either. When reinforced with steel rods to take care of the tensile loads it is indeed VERY STRONG.
The concrete in the WTC tower floors was a lightweight version with perlite* admixed. It is indeed easy to smash it with a sledgehammer, and even easier to smash it with a hammer weighing, say, a hundred thousand tons.
The steel in the WTC tower structures was surrounded by a weak foam concrete which didn't resist the impact blast. Where it was stripped it wasn't protected from the following fire.
You need to get a grip.
* Similar to pop-corn, but instead of starch "puffs" you have asbestos "puffs". It is made by quickly heating vermiculite.
Last edited by Jazzy; March 3rd, 2013 at 01:05 PM.
What a surprise... you know better than the designers and engineers who constructed them.
A factor of 12 you say... care to back that up?
Or should I expect 'look' and 'internet' in any response?
You have the right to remain silent but is that really a good idea?
What was not accounted for was an uncontrolled fire with removed insulation (in WTC1 and 2) and an uncontrolled fire for 8 hours with no sprinklers or firefighting (WTC7)
Only if there was a delay between collapses. Here one led directly to the next, and then it was all falling.
Posting Permissions
Reply With Quote
Bookmarks