September Clues Addendum Chapter 1

[nik]

Thanks icosa

[JazzRoc]

Note that snapped column-ends face inward - which rules out ANY internally-placed explosion.

I repeat, what forensic case might be made for this hole?
What shape is it?

The above is a simple question. What stops you from answering it?

If your mind is BLANK, you may refer to THIS.

Nutty 9-11 Physics - Steven Dutch, Natural and Applied Sciences, University of Wisconsin - Green Bay

No amount of evidence will dissuade a conspiracy theorist, but when they appeal to scientific evidence, they're fair game. And the 9-11 conspiracy sites have some very strange science.
9-11 conspirators seem to be a mix of liberals still smarting over 2000 and ultra-conservatives angry that George Bush Jr. hasn't opened the national parks to a land rush. But if Dubya orchestrated a massive conspiracy to bring down the World Trade Center as a pretext for launching a Mideast War, why didn't he pull off the far simpler trick of faking the discovery of weapons of mass destruction in Iraq? Think of it - his biggest political liability could have been avoided with a piddling investment in special effects, Bush would be seen as America's savior, his strategy would be completely vindicated, and he'd be politically unassailable. All it would take would be spritzing an empty factory with the ingredients for nerve gas, with just enough cross-contamination to create a whiff of the real thing. Yet for some strange reason he didn't do it.

"Cause and Effect"
We live in a universe of patterns. Once a pattern is established, the burden of proof is on people who claim the pattern does not hold. When some philosopher of science points out that we cannot prove that the sun will rise tomorrow, I say he's absolutely right. There is no way to prove axiomatically that the sun will rise tomorrow, and nobody in science cares in the slightest. When the sun doesn't rise as scheduled, call me. Until then I absolutely refuse to waste time worrying about it. When Immanuel Velikovsky claimed the planets underwent wild disturbances in their orbits, the burden of proof was on him to show that it happened. The burden was not on scientists to show it didn't.
In the case of 9-11, we have planes hitting the World Trade Center and the buildings failing at precisely the level of impact. The observational evidence clearly shows a cause and effect relationship.

"It Looks Like A Controlled Demolition"
What else is a large building collapse going to look like?
Until 9-11, our only experience in bringing down very large buildings was controlled demolition. The highest buildings (apart from broadcast towers) brought down were in the 30 story range. Once the building starts to fall, the physics is going to be the same regardless of the initial cause. So alleged similarities between 9-11 and controlled demolitions prove nothing. You might as well argue that the collapse of Mount St. Helens in 1980 was set off by explosives because it looked just like a landslide caused by explosives.
One thing radically different about 9-11 is that controlled demolitions always set off charges low in the structure and let the weight of the building do the rest. Nobody ever set off charges high in a building to pancake the stories beneath. So why resort to a radical and unproven method if you want to bring down the World Trade Center?
Probably the most revealing commentary on the controlled demolition theory is Bringing Down The House by Michael Satchell in US News and World Report (June 30, 2003). This article describes the work of Controlled Demolition Inc., far and away the world leaders in controlled demolition, and Mark and Doug Loizeaux, who run it.
Like most Americans, the Loizeauxs were transfixed by the televised scenes of destruction shortly after the first jet struck. But as experts in buildings' vulnerabilities, they knew right away what few Americans realized. "I told Doug immediately that the tower was coming down, and when the second tower was hit, that it would follow," remembers Mark.
Horrified, the Loizeaux brothers watched first responders streaming into the doomed towers and tried frantically, and unsuccessfully, to phone in warnings. In the following days, CDI was called to ground zero to consult on safety and develop plans for demolition and debris removal. What if the twin towers, though badly damaged, had somehow remained standing? Without doubt, the Loizeaux family would have been called upon to bring them down. "Quite simply," says Mark in a rare moment of introspective uncertainty, "I don't know how we would have done it."
So according to the world experts on building demolition:
* It was immediately obvious that the towers were going to fall
* They have no idea how they would have brought down the towers in a controlled demolition.
Of course, you can always claim the Loizeaux brothers were in on the plot. Some sites link to a story about Controlled Demolition later being charged with illegal campaign contributions, which certainly proves something. Or other.
Actually, the collapse doesn't look like a controlled demolition. Real controlled demolitions try very hard to avoid flinging debris far beyond the building itself. They blow the lower stories and the center of the building to cause the building to collapse in on itself. The collapse of the World Trade Center doesn't look remotely like a controlled collapse, apart from stuff falling down.
Implosion World, a site dedicated to controlled building collapse, agrees (http://www.implosionworld.com/wtc.htm)
DID THE WORLD TRADE CENTER TOWERS ACTUALLY “IMPLODE”? No. They collapsed in an uncontrolled [emphasis added] fashion, causing extensive damage to surrounding structures, roadways and utilities. Although when viewed from a distance the towers appeared to have telescoped almost straight down, a closer look at video replays reveal sizeable portions of each building breaking free during the collapse, with the largest sections--some as tall as 30 or 40 stories--actually “laying out” in several directions. The outward failure of these sections is believed to have caused much of the significant damage to adjacent structures, and smaller debris caused structural and cosmetic damage to hundreds of additional buildings around the perimeter of the site.
HOW DOES THIS EVENT COMPARE WITH A NORMAL BUILDING IMPLOSION? The only correlation is that in a very broad sense, explosive devices (airplanes loaded with fuel) were used to intentionally bring down buildings. However it can be argued that even this vague similarity relates more to military explosive demolition than to building implosions, which specifically involve the placement of charges at key points within a structure to precipitate the failure of steel or concrete supports within their own footprint. The other primary difference between these two types of operations is that implosions are universally conducted with the utmost concern for adjacent properties and human safety---elements that were horrifically absent from this event. Therefore we can conclude that what happened in New York was not a “building implosion.”
Check out the videos of the demolition of the Stardust Hotel in Las Vegas. Fireworks. Big pyrotechnic countdown clock. None of that on 9/11. Not even remotely similar. Silly? Yes, but still above the intellectual level of most 9/11 conspiracy theories. I mean, the similarities the conspiracy buffs point to are on the same level of superficiality as whether or not there were fireworks.

"Jet Fuel Doesn't Get Hot Enough to Melt Steel"
For the umpteenth time, nobody ever claimed the steel melted. It got hot enough to lose its strength.

"So Where Did All The Molten Steel Come From?"
There are lots of accounts alleging that rescue workers encountered molten steel. The first question that comes to mind is whether these witnesses know the difference between incandescent and molten. Steel can get hot enough to glow long before it gets hot enough to melt. The fact that glowing steel was pulled out of the rubble doesn't mean it was molten.
One particular red herring that crops up frequently is that temperatures in the rubble were high enough long after the collapse to melt aluminum. Since aluminum melts at 660C (1220F) I don't have the slightest doubt of it. Since a backyard trash fire can melt aluminum, so what?
Apparently, the melting of steel signifies the use of explosives or thermite cutting charges. But the purpose of either is to cut steel, not melt it. A controlled demolition simply does not produce large amounts of molten steel. You might as well argue that all the concrete dust shows the buildings were taken down by an army of gnomes armed with grinding wheels.

"If the World Trade Center was hot enough to melt steel, where's all the molten concrete?"
Iron melts around 1500C but so do many of the silicate minerals in concrete, and a mixture of silicate minerals would melt at a temperature lower than any of the individual minerals (I'm a geologist - I get paid to know about stuff like that). The fine particle size of the concrete dust would facilitate melting. So why wasn't there a huge puddle of molten concrete at Ground Zero? (There was some, but about what you'd expect from a large fire; certainly not what you'd expect from something hot enough to melt large amounts of steel.)
In a paper by Steven E. Jones, who bills himself as a "Physicist and Archaeometrist," there are pictures of glowing material falling from the World Trade Center, together with this comment: "Who can deny that liquid, molten metal existed at the WTC disaster?
The yellow color implies a molten-metal temperature of approximately 1000C. 1000C, is about 500C below the melting point of iron. Oh, by the way, there would have been cutting of steel during the construction. And there's another construction process that melts steel. Welding.

"No Steel Frame Building Has Ever Collapsed Due To Fire"
So if something happens for the first time, it can't happen because it never happened before?
No 110-story buildings were ever hit by fuel-laden airliners hard enough to strip the insulation off the structural steel before, either. Steel-frame buildings are incredibly strong. They have survived major earthquakes and fires, and the Twin Towers merely rocked when hit by airliners at full throttle. But the towers were not designed to survive an impact by fully-laden airliners at full throttle, then a fire in contact with unprotected steel. An impact from a jet approaching JFK at 200 miles an hour, with nearly empty tanks, and one slamming into the building at 450 miles an hour with full tanks, are two quite different things.

"Free Fall"
According to Roedy Green's How You Know 9-11 Was an Inside Job: "All three World Trade Towers fell faster over the first half of the collapse than physics allows by free fall. That meant they had to have an assist, e.g. an explosive push from pre-planted demolition charges, not just gravity pulling them down. The maximum collapse for free fall is computed by distance = g t where g is the acceleration due to gravity 32 feet per second per second, and t is time in seconds. In other words, free fall collapse should start out slowly and accelerate faster and faster for the big finale."
This is just plain weird. Whether a building falls by deliberate demolition or catastrophic failure, the collapse will be governed by gravity. Even if you used a teleporter to magically make several stories vanish, the part above would only fall as fast as gravity would accelerate it. Only if there was some kind of thruster pushing the building down could it fall faster. Why install a useless Rube Goldberg device? Once the building begins to collapse, who needs anything to accelerate it? Gravity has a pretty reliable record of pulling things down. And where's the evidence for faster than free fall collapse?
The videos show that the towers took 15 seconds to collapse. The free-fall time for something to fall 400 meters is about 9 seconds. So, no, the towers did not fall faster than free fall.
911Research claims: "This rate is still much too fast to be explained by a gravity-driven collapse given that the descending rubble would have to crush and accelerate almost 1000 feet of vertical intact structure. It is especially revealing that each tower disappeared at about the same rate as the rubble fell through the air, as if the tower's structure provided no more resistance to the descent of rubble than did air."
All photos of the collapse show a plume of debris extending far below the main level of collapse. So the debris did fall appreciably faster than the building itself. The building provided little more resistance than air for the simple reason that a skyscraper is mostly air. In the photo at left the collapse is about where the cloud fills the entire width of the picture, but the debris in free fall has almost reached the ground.
Note that the debris is at least a building width beyond the building itself. No competent controlled demolition flings debris that far.
The fall doesn't have to crush the stories beneath. It merely has to stress the structural elements until the fasteners pop and the welds break. The impact of that pancaking material will cause the outer vertical members to bow outward, then fly outward violently when failure occurs. There's no need to appeal to explosives to fling material outward from the buildings.
If a story is 4 meters high, it will take an object about 0.9 seconds to fall one story, by which time it will be going 9 m/sec. So once the collapse starts, the overlying structure will be falling at 9 m/sec by the time it has fallen one story. If we crush the collapsing story into rubble half a meter thick and expect the collapse to stop at that point, what kinds of forces are involved? We go from 9 m/sec to zero in half a meter, or 1/18 of a second. However, during that deceleration the velocity is decreasing, and the average velocity turns out to be half of the initial velocity, so the crunch time is 1/9 second. So the acceleration is -9 m/sec divided by 1/9 sec = -81 m/sec2, or about 8 g's.
This is the difference between a static load and a dynamic load. In the north tower, with about ten stories above the impact, the dynamic load was about equivalent not to ten stories but to eighty, nearly the total height of the building. I doubt if the tower at that level was engineered to support eighty stories - why waste the steel? Actually the loads are much greater because the initial collapse involved a fall of about three or four stories, not just one, and the dynamic loads on the points that actually resist the fall - the welds and the rivets, will be far greater. If you try to stop the collapse in the millimeter or so a rivet or weld can deform before failing, you're talking hundreds of g's. In the south tower, where the top 25 or so stories fell, the impact load at eight g's would be equivalent to 200 stories, or twice the total height of the building. Some conspiracy buffs argue that engineering standards require a safety factor several times the actual load on the structure, but the dynamic loads would far overwhelm those standards.
This, by the way, is the reason controlled demolition works at all. If physics worked the way 9-11 conspiracy buffs think, once you blew the lower stories of a building, the upper part would just drop and remain intact. Of course it doesn't because once the building begins to fall, the dynamic loads are far beyond the static strength of the building.
911Research devotes a lot of effort to debunking what it regards as disinformation campaigns designed to deflect attention from the theory of controlled demolition. But we keep coming back to the fundamental issue how any building can fall faster than gravity or why a conspirator would feel the need to set up a mechanism to do something so useless.

"But the Government Said So"
9-11 troofers keep blind-siding me because they keep on coming up with things I can't believe any toilet-trained human being would be dumb enough to say. Lately I've been hit a couple of times with the assertion that the 9-11 Commission Report states, on Page 305, that "At 9:58:59, the South Tower collapsed in ten seconds" Indeed it does. The 9-11 Commission Report deals with events leading up to 9-11, agency responses to the crisis, and possible changes in procedure and policy to cope with future crises. It contains no technical information whatsoever about the causes of the building collapse. Nevertheless, because the report says the South Tower collapsed in ten seconds, 9-11 troofers insist that is the official Government position.
People who take that stance aren't merely scientifically illiterate; they're verbally illiterate as well. Insisting that ten seconds is meant to be a scientifically definitive finding in a paragraph dealing with firefighting efforts shows a complete lack of critical reasoning. A person who reasons like that is completely lacking in the critical reasoning necessary to sort out the events of 9-11.
The technical information on the building collapse is in the NIST reports, not the 9-11 Commission Report. There is little discussion of the chronology of the collapse once the buildings began to fall, but the NIST FAQ (Frequently Asked Questions) site has the pertinent information.
The seismic spikes for the collapse of the WTC Towers are the result of debris from the collapsing towers impacting the ground. The spikes began approximately 10 seconds after the times for the start of each building’s collapse and continued for approximately 15 seconds.
So according to the seismic record, the first impacts are about ten seconds after the onset of collapse. That's the free-falling debris. Seismic signals continued for 15 more seconds. So it took at least about 25 seconds for the buildings to collapse. The seismic records are probably the best information because the last stages of collapse were obscured by dust, but a time indexed series of video frames on the 9-11 Research site shows the collapse of one tower still in progress after 19 seconds. So the collapse speed was less than half of free-fall speed.
Also:
From video evidence, significant portions of the cores of both buildings (roughly 60 stories of WTC 1 and 40 stories of WTC 2) are known to have stood 15 to 25 seconds after collapse initiation before they, too, began to collapse. Neither the duration of the seismic records nor video evidence (due to obstruction of view caused by debris clouds) are reliable indicators of the total time it took for each building to collapse completely.
And the people who like to take "ten seconds" and "essentially in free fall" literally don't seem to care much about paragraphs like this: "In other words, the momentum (which equals mass times velocity) of the 12 to 28 stories (WTC 1 and WTC 2, respectively) falling on the supporting structure below (which was designed to support only the static weight of the floors above and not any dynamic effects due to the downward momentum) so greatly exceeded the strength capacity of the structure below that it (the structure below) was unable to stop or even to slow the falling mass. The downward momentum felt by each successive lower floor was even larger due to the increasing mass."
9-11 troofers are a lot like some Biblical fundamentalists. Anything that they want to believe is to be taken with absolute literalness, and anything that contradicts what they want to believe, they just ignore.

"The Buildings Collapsed Straight Down"
Gravity tends to do that. You can't extrapolate what happens in the collapse of a small building, which may tilt intact, to what happens in the collapse of a 110-story building. The videos show clearly that the top floors of the South Tower did tilt during the first few seconds of collapse.
A lot of conspiracy sites talk about "sequential collapse" as if there were explosive charges placed on every floor detonated in sequence, like the destruction of the Empire State Building in Independence Day. But controlled demolitions don't do that - they use a small amount of explosives and let the weight of the building do the rest. Thirty-story buildings have been brought down with only a few hundred pounds of explosives.

"The Concrete Is All Pulverized"
What exactly did you expect? Actually photos of the site show lots of concrete, admittedly broken into small chunks. Falling 1000 feet, or having stuff fall from 1000 feet onto something else, will pulverize it. Firefighters reported that no office furnishings were recognizable either. Did somebody rig a bomb to every single desk, chair, computer and telephone in the buildings?

"Too Much Dust"
From 911Research: "If the collapses were merely gravity-driven, then any clouds of debris produced in the immediate aftermath should have occupied about the same amount of space as the intact towers before they had time to significantly mix into the surrounding air. The bulk of the clouds could only come from the expulsion of gases in the buildings as they collapsed, and the mixing of ambient air into the clouds."
This just makes me shake my head in wonder. First, the expulsion of air from the towers would have been pretty impressive, second, air rushing in to fill the space formerly occupied by the towers would have been equally impressive. Falling debris would also have displaced a large amount of air. Together they would have created a huge amount of turbulence, just what was seen at Ground Zero.
Actually the dust cloud at street level bore a remarkable visual resemblance to a pyroclastic flow, a hot, dense mixture of volcanic ash and gases. The dust cloud was cool, but the cloud itself was a density flow, a mixture of dust and air much denser than normal air. Density flows, whether in air or water, maintain their identity for quite a while. They stop moving when they run out of momentum, the denser parts of the flow settle out, and the lighter parts mix with the surrounding medium. Now here's a theory for conspiracy buffs to toy with - maybe someone triggered a volcanic eruption under the Twin Towers.
I should know better than to ridicule conspiracy theories on line. I simply don't have enough imagination to top what conspiracy theorists actually come up with. If you search 9-11 and "pyroclastic," you will find sites that assert the dust cloud was an actual pyroclastic flow. I could assist these folks in learning the difference. All they need to do is find an active volcano and stand in the path of a real pyroclastic flow. I guarantee it would cure them of posting nutty stuff on the intartubes. The drywall used around the central core of the towers was an inch and a half thick. Now that will create a lot of dust.
Somehow the collapse of a quarter-mile tall building was supposed to produce no turbulence so that the dust cloud would remain over the footprint of the building and mix gradually with still air. Shades of the Road Runner, who goes "beep-beep" and leaves a road-runner shaped dust cloud behind. This is physics several levels beyond weird.
A lot of people confuse optical density with amount of dust. The fact that the dust cloud was opaque means only that light didn't penetrate it. The clouds that hung above the site weren't much denser than air so the total volume of dust in them was not large. Typical clouds in the sky contain a few grams of material per cubic meter. If we assume the 9-11 cloud had 10 grams per cubic meter - far more than even thick water droplet clouds, and the dust cloud occupied a cubic kilometer, far more than its actual volume, we have a billion cubic meters times ten grams per cubic meters, or ten billion grams, ten million kilograms, or 10,000 tons of dust, paltry compared to the million ton mass of the towers.

"The Crime Scene Was Not Preserved"
So what exactly were 52 FBI Evidence Recovery Teams, totaling more than 400 agents, doing on Staten Island for nine months? This just in, the FAA doesn't leave the debris from plane crashes in place either; they take it to a hangar and lay it out for study. Paired up with this question is why the cleanup trucks were so carefully monitored with GPS units. These days, trucks routinely have GPS units, so that's not particularly unusual, especially since a truck driver could probably sell a load of 9-11 steel for a tidy sum on the souvenir market. One driver who took a 1-1/2 hour lunch was fired, but that can get you fired lots of places. So not leaving the debris in place is evidence of a plot, and tracking it en route to make sure it gets where it's supposed to go is also evidence of a plot.
The people clearing the site and examining the debris were responsible for removing a continuing hazard, recovering human remains, and finding any evidence that might shed additional light on what the obvious visual record shows - that the buildings collapsed after being hit by aircraft. They were not responsible for doing an archeological dig to satisfy the objections of every conspiracy theorist on the planet. Don't like that? Too bad. Deal with it.
When I did a radio interview with a truther a while ago, the discussion came around to temperatures in the fire. According to government reports, samples from the floors where there were fires showed only a few indications of very high temperatures. A much more significant question is this: if evidence wasn't properly collected, how did investigators know which floors the debris came from? Ironically, the fact that personal effects of hijackers and passengers were found is not evidence that evidence was carefully sifted, for some odd reason.

"Seismic Evidence" - Again, from Roedy Green:
Seismic evidence shows the two main world trade towers were taken down by demolition.
The link goes to a site of Columbia University's Lamont-Doherty Earth Observatory showing seismic records of the plane impacts and tower collapses. The impacts registered below magnitude 1, the collapses a bit over magnitude 2. The records look like perfectly ordinary seismograms. There's no elaboration on how exactly the seismic evidence shows demolition.
Apparently some conspiracy thinkers believe a seismic imprint must mean an explosion, but the collapse of a large building will do very nicely. Oil companies routinely do seismic soundings by dropping masses of several tons, called "thumpers," to generate seismic waves. A million-ton building will make a very good thumper.
Other sites look in detail at the seismograms, arguing that a slow buildup of the signal shows a progressive use of explosives. But a building collapse spread out over 15 seconds will produce a signal of growing amplitude.

"Why Did WTC 7 Collapse?"
Good question. The investigators were baffled. But the conspiracy theory doesn't explain anything. Why bring down an empty building hours after the main attack?
Photos published to support the claim of a controlled demolition show puffs emerging from the top of the building. These could be explosives. Or they could be concrete suddenly failing, or windows shattering. But again we have the irritating question, why start a collapse from the top, completely at odds with the way all controlled demolitions are done, especially if you want the building to fall onto its own footprint?
If it was actually a controlled demolition by the Fire Department or the building owner, or both, as some people allege, so what? The remains of the World Trade Center itself were brought down in controlled demolitions after 9-11. What does that have to do with the collapse of the Twin Towers? It seems unlikely that a demolition crew would enter a burning building and install charges to bring down something 15 stories taller than any other recorded controlled demolition, all in the space of a few hours, but if the building was brought down by the owners or the Fire Department, what's the connection to the Twin Towers? How does a planned demolition of one building prove the Twin Towers were deliberately brought down?
I've gotten a fair amount of flak over this issue but I've yet to see anyone present a coherent explanation of what, exactly, the collapse of WTC-7 proves.

"Complexity"
"Osama Bin Ladin, sitting in a cave in Afghanistan, could never have pulled off something of this complexity."
What complexity? You put 19 guys on four airliners on the same day armed with box cutters, after first giving a few of them enough flight training to allow them to perform some rudimentary maneuvers. Any travel agent who couldn't book 19 people on four separate flights on the same day needs a new job. The complex part would have been gaining and keeping control of the passengers and crew once the hijacks were in progress.
If Bin Ladin had known what would happen, he would certainly have had the hijackers hit the buildings lower. That would have trapped far more people while increasing the load on the heated steel, resulting in faster collapse. So if it wasn't Bin Ladin, why didn't the alleged conspirators do it? More outrage, more backing for the War on Terror. Why did they miss such an obvious opportunity?

"Suppose It Was A Conspiracy"
What was the intent? If it was to bring down the Towers, why demolish from the top down? That's not how any other controlled demolitions are done. Why not strike low, maximizing the number of casualties and more fully galvanizing the country for war?
If the intent was to collapse only part of the Towers, keeping casualties limited but providing a pretext for war, then the total collapse was unanticipated. Or maybe the intent was simply to crash planes into the Towers and produce casualties but not cause building collapse at all. In either case, if the building collapses were unexpected, they happened through structural weakening and gravitational collapse and all the alleged "evidence" for sequential explosive charges and so on becomes worthless.
Why use planes at all? Why not simply stage a bigger and better remake of the 1993 attack? Why not claim the terrorists detonated a large truck load of explosives at the central core of the building, or smuggled explosives into the core? Instead of passenger planes, why not have the terrorists steal a FedEx or UPS cargo plane and fill it with explosives?
Why have a time gap between the plane crashes and building collapse, and why did the South Tower, which was hit later, fall first? That makes perfect sense in the conventional scenario, because the South Tower was hit lower and thus the load on the damaged structural members was greater. It makes no sense at all from the standpoint of a conspiracy.
Like all conspiracy theories, the 9-11 conspiracy idea suffers from the fatal flaw of having the conspirators engage in a complicated Rube Goldberg process to do something a rational person could do more effectively in a much simpler way.

The Ultimate Best Words on Conspiracies - Jonah Goldberg, Skepticism Versus Paranoia, The Corner, National Review On Line, Wednesday, September 13, 2006
"I distrust the government but as a realistic conservative I think government is staffed with mostly well-intentioned but incompetent people — not because they're dumb, but because bureaucracies are dumb.
These conspiracy theorists reverse this entirely. They think government is evil-intentioned but supremely, even divinely, competent. That's crazy-talk, Count Chocula."
Neal Boortz is a conservative-libertarian talk show host who gets under a lot of folks' skins, but he has one saving grace. He's death on conspiracy theories (and creationism). A listener e-mailed him asking him to explain about "chemtrails," which the government is supposedly using for mind control. His reply works just as well for 9-11 conspiracy thinkers.
"OK, Jim. I'll explain. You're a nutcase. Those "chemicals" you think the military is spraying on citizens are nothing more than ice crystals formed by the condensation created by high-flying aircraft. Somewhere along the line some lonely demented hysteric decided that the military was crop-dusting people with all sorts of chemicals designed to make us sick, change our behavior or neuter us. I have no idea in the world what went wrong in your education, upbringing or mental health history that caused you to actually believe this insane nonsense ... I can only hope that you don't vote."
Then there's Mark Steyn's wonderful observation:
"There's a kind of decadence about all this: If 9/11 was really an inside job, you wouldn't be driving around with a bumper sticker bragging that you were on to it. Fantasy is a byproduct of security: it's the difference between hanging upside down in your dominatrix's bondage parlor after work on Friday and enduring the real thing for years on end in Saddam's prisons."
I think it's rather interesting that, although you find moonbat leftists and rightists alike arguing for an inside job, all the comments above come from rock solid conservatives.

"Dueling Conspiracy Theories"
Since a lot of people have begun to catch on to conspiracy theories, 9-11 theorists have begun putting their own spin on the term. Just like creationists have begun using the word "pseudoscience" to brand evolution and blur the distinction between their own ideas and those of science, 9-11 conspiracy theorists have begun using the term "conspiracy theory" to label the conventional view of 9-11. So you get 19 guys, give some of them rudimentary flight training, they board airliners, hijack them, and fly them into buildings. Yup, that's a conspiracy all right. So the term "conspiracy theory" is entirely accurate.
On the other hand, government operatives spent days planting explosive charges in the towers, then crashed the airliners or flew them to a secret location, brainwashed, imprisoned, or killed the passengers and crew, and that's not a conspiracy theory? Or the videos of the airliner crashes are all fake and some exotic particle beam or energy weapon disintegrated the towers into dust and that's not a conspiracy theory, either?
Well, they're both conspiracy theories, so they're both on the same plane, so you get to pick whichever one you like. This is the classic relativism of the pseudoscientist.
Fortunately, there's a way to sort through the conflicting claims.
Which of the two is more consistent with well known facts? Do Middle Eastern terrorists hijack airplanes? Check. Do Middle Eastern terrorists target civilians? Check. Do Middle Eastern terrorists deliberately cause mass casualties? Check. There's absolutely nothing in the standard picture of 9-11 that conflicts with these facts. Number of previous cases where U.S. government operatives have hijacked airliners? None known. Number of previous cases where the U.S. government has collapsed a building full of innocent people? None known (apart from artillery or bombing in war). Number of previous cases where the U.S. government has collapsed a building full of its own citizens? None known.
So one conspiracy theory has a host of historical precedents, and the other has none at all.
Fascinating, isn't it, that the fact that no steel frame skyscraper had ever collapsed due to fire is touted as ironclad proof that planes couldn't have brought down the World Trade Center, but the total absence of historical precedent for the government doing it counts for nothing?

"Who Stands to Profit?"
A question much asked by 9-11 truthers, who point to gold allegedly being removed from the World Trade Center, investigative files being destroyed, a pretext for invading Iraq or declaring martial law, etc.
A few months ago I agreed to be on a truther talk show (I'll try almost anything once. Almost.) and the commercial breaks were a revelation. There were endless spiels for crank medical remedies and nutritional supplements, investment schemes that ranged from shady to crazy, newsletters for conspiracy cults, and wacko theories on how to avoid taxes. One former truther who became disillusioned said he would no longer help the movement sell T-shirts and DVD's. It's a lot more than just T-shirts and DVD's. Look at the Web sites, the newsletters, listen to the talk shows and look at who's bankrolling them and advertising on them. Truther sites are to conspiracy thinkers what televangelists are to lonely Christians: a place to send money to buy a feeling of participation and fulfillment.

Feedback
Physics is quite clear on this....if random fires and structural damage was all it took to bring down buildings (onto their footprint, at free fall speed) why would there be demolition companies? Just start random fires and damage the top, the building will disintegrate... not likely...
The towers didn't collapse onto their own footprint, not by a long shot. They didn't topple like trees, but debris flew and did damage a long way away. The whole reason we have controlled demolitions beginning at the base of buildings is to prevent debris from flying as far as it did on 9-11.
I know this sucks, I was a Republican... I understand how much it seems crazy, but please, I beg of you, as an American... look at the facts... forget about politics for a minute... just look at the physics. Look at the videos, there are many (of the towers falling and building 7)....
Forget about politics? Politics is hardly mentioned at all in the discussion above, which does "just look at the physics." The only people who are constantly dragging politics into the discussion are the 9-11 conspiracy believers.

"I have read what you said on the internet about the collapse of the towers. First I find it unprofessional the constant use of the pejorative to make your case..."

Really?
9-11 conspiracy buffs can slander government officials, accuse them of mass murder and conspiracy, and ridicule their critics, and I'm being pejorative? If people are going to talk like that they should at least have the guts to take criticism. The conspiracy buffs supposedly have the courage to expose a massive high level conspiracy, but they whine like pre-schoolers when anyone attacks their ideas. Some courage. They can play these games because they know perfectly well that nobody is really going to do anything to them no matter how much they blather about conspiracies. It's all play acting. How else can you call bullshit what it is without being pejorative?
The amazing thing is this guy can slander people he's never met and who have done him no harm, and somehow he thinks that is acceptable professional behavior. You can't have a meaningful conversation about professionalism with this guy any more than you can play chess with a duck.

Nik, the fact that you NEVER address the FACT of the plane-shaped hole is VERY telling.
If you believe it to be inconsequential, then please tell me why.

[nik]

"Nik, the fact that you NEVER address [me]the "FACT" of the plane-shaped hole is VERY telling."

Indeed, but what it is very telling of is a different matter.

---

Quote:"Who Stands to Profit?"
A question much asked by 9-11 truthers, who point to gold allegedly being removed from the World Trade Center, investigative files being destroyed, a pretext for invading Iraq or declaring martial law, etc.
A few months ago I agreed to be on a truther talk show (I'll try almost anything once. Almost.) and the commercial breaks were a revelation. There were endless spiels for crank medical remedies and nutritional supplements, investment schemes that ranged from shady to crazy, newsletters for conspiracy cults, and wacko theories on how to avoid taxes. One former truther who became disillusioned said he would no longer help the movement sell T-shirts and DVD's. It's a lot more than just T-shirts and DVD's. Look at the Web sites, the newsletters, listen to the talk shows and look at who's bankrolling them and advertising on them. Truther sites are to conspiracy thinkers what televangelists are to lonely Christians: a place to send money to buy a feeling of participation and fulfillment.

That's a good one! What a beautifully succinct bullshivist answer to the proposed deconstructive question. Misdirect agogo. Push the boat out, why not, eh?

[JazzRoc]

(08-29-2010 09:34 PM)nik Wrote:  what it is very telling of is a different matter

NO. It is THE matter.

Quote:Misdirect agogo. Push the boat out, why not, eh?

Other people's hypocrisy always makes me cringe. Must go...

(I was going to joke, and had "sneeze" where I have now written "cringe" - but that would have been bullshit, so... no. I want to tell you that the words I pulled off that link I would have been quite happy to have written myself. I think it's sickening that you get your kicks out of USING those terrible events and hapless victims to needlessly slander other innocents and block and frustrate and obscure access to whatever the REAL truth might have been, both in the past, the present, and possibly even the future.
I can feel that the continual dwelling on these events, your lies, and the persistent tragedy of all of this is depressing me, and I think it has "tipped" you. Good luck, Nik.)

[icosaface]

Wouldn't want newbees to get the impression that jr wasn't a psyop, ergo the following.

Quote:No amount of evidence will dissuade a conspiracy theorist, but when they appeal to scientific evidence, they're fair game. And the 9-11 conspiracy sites have some very strange science.
9-11 conspirators seem to be a mix of liberals still smarting over 2000 and ultra-conservatives angry that George Bush Jr. hasn't opened the national parks to a land rush. But if Dubya orchestrated a massive conspiracy to bring down the World Trade Center as a pretext for launching a Mideast War, why didn't he pull off the far simpler trick of faking the discovery of weapons of mass destruction in Iraq? Think of it - his biggest political liability could have been avoided with a piddling investment in special effects, Bush would be seen as America's savior, his strategy would be completely vindicated, and he'd be politically unassailable. All it would take would be spritzing an empty factory with the ingredients for nerve gas, with just enough cross-contamination to create a whiff of the real thing. Yet for some strange reason he didn't do it.

The US supplied Sadam with biological weapons, all Bush had to do was whip out the bills of laden.

Quote:"Cause and Effect"
We live in a universe of patterns. Once a pattern is established, the burden of proof is on people who claim the pattern does not hold. When some philosopher of science points out that we cannot prove that the sun will rise tomorrow, I say he's absolutely right. There is no way to prove axiomatically that the sun will rise tomorrow, and nobody in science cares in the slightest. When the sun doesn't rise as scheduled, call me. Until then I absolutely refuse to waste time worrying about it. When Immanuel Velikovsky claimed the planets underwent wild disturbances in their orbits, the burden of proof was on him to show that it happened. The burden was not on scientists to show it didn't.
In the case of 9-11, we have planes hitting the World Trade Center and the buildings failing at precisely the level of impact. The observational evidence clearly shows a cause and effect relationship.

Holy ignoramus, listen Bub, the Sun does not rise. It never has. Get some help before you go completely senile eh!
In the case of 911 we have firefighters, first responders and World Trade building residents testifying that bombs were going off all over the towers.

WTC 1 - Learning from Ship Collisions by Anders Björkman (M.Sc),

Quote:The WTC 1 Tower could not have been one-way crushed down and destroyed by its upper part dropping on it on 9/11/2001. This presentation explains why, i.e. there is too little energy available to destroy the lower structure. That's why houses and towers never globally collapse from top down. It will take 30 minutes to read the presentation! Please tell me what you think!

The author is a naval architect with 40 years of steel structural design experience including structural damage analysis. He has investigated the structural damage from many ship collisions. The destruction of WTC 1, a plane colliding with a steel framed tower and what follows, e.g. upper part of WTC 1 dropping on/impacting lower structure, is in many respects similar to a collision between two steel ships!

At the moment of contact of A) the 'WTC 1 upper part and lower structure' or B) 'two ships in collision', a certain momentum (mass times velocity), kinetic energy (momentum times velocity divided by 2) and forces (energy divided by displacement) have to be considered.

All structural elements involved are subject to displacements and local failures due to the forces applied; energy is absorbed and consumed, friction forces between failed/displaced elements in contact develop, forces and loads are re-distributed, momentums are reduced as outer forces are applied on the parts and the environment and the destruction is always arrested after a while. All kinetic energy of the collision is transformed into heat and the momentum is transmitted to ground/Earth (very big mass part of the collision).

Structural Damage Analysis

It is not a static or dynamic solid mechanics problem! It is a structural damage analysis matter! The upper part of WTC 1 can only apply forces on the lower structure elements that the upper part can itself withstand in the first place. As the upper part and the lower structure of WTC 1 have identical structures, the upper part cannot destroy the lower structure of WTC1 in a top-down collapse. In ship collisions, where different types of structure come into contact, the situation is slightly different but identical principles of analysis apply. Both structural parts deform and maybe damage each other.

What happened to the smaller upper part of WTC 1 colliding with/dropping on (?) the bigger lower part on 911 can be seen on photos below (origin of photos is Internet and reliability, photo being real or fake, cannot be guaranteed):


Fig. A1 - The upper part C (floors 97-110 + mast) rests on the lower part! Destruction has not started. At right insert is shown upper part in original position.


Fig. A2 - Destruction and collision (sic) have started!! The upper part C (floors 97-110 + mast) (95% air) is destroyed, while roof line and mast move down 5 floors or 18-19 meters. It, the upper part, should however remain intact and not get smaller and it should now crush down WTC 1 lower structure according US authorities!


Fig. A3 - The upper part C (floors 97-110 + mast) is completely destroyed but mast can still be seen. Debris is ejected sideways at high velocity.


Fig. A4 - The WTC 1 lower structure top part explodes in a cascade of debris! The upper part C and mast is fully destroyed and cannot produce what we see! It looks as if a bomb has gone off inside WTC 1 blowing debris sideways. No upper part C is crushing down anything here!


Fig. A5 - More debris is thrown out sideways (more bombs go off!) and smoke is ejected upwards! Evindently not a result of the upper part C being intact and crushing down lower structure as per US authorities. It, the upper part, has already disappeared or gone up in smoke.



Fig. A6 - There is no sign of an intact upper part crushing WTC 1! Why does US authorities suggest that a skyscraper can be destroyed by a small top upper part one-way crushing down much stronger, bigger structure below by gravity and fire up top? Anybody can see on photos above that WTC1 is blown apart from top down and that the upper part is blown apart first. One question remains; can we trust the photos?

Actually an upper part crushing anything would have been impossibe, because Björkman's axiom regarding structural damage analysis of identical structures in collision says:

A smaller, upper part of an isotropic or composite 3-D structure, when dropped on and impacting a greater part of same structure by gravity, cannot one-way crush down the greater, lower part of the structure.

The upper part should in fact have remained stuck up top on say floor 94, if some local failures due to fire occured there! What was seen and recorded above is pure show or terror business - choreographed for maximum exposure, maximum emotional effect, and maximum replay drama. What could have been more dramatic than what the Americans saw - over and over and over again - on 911? But physically and from a structural damage analysis point of view it is not possible.

Quote:The Björkman axiom explained

The Björkman axiom can be better understood by looking at what happens when two objects C and A collide inelastically, i.e. the objects are deformed/damaged in an isolated space (in some simple, numerical examples):

We start with two objects C and A of same mass (and other structural properties). Note how the velocity of the moving part C changes (is reduced) at collision!

C has mass m = 1 kg and is moving at velocity v = 10 m/s and its kinetic energy (mv²/2) is 50 J and its momentum (mv) is 10 kgm/s. A has mass 1 kg but is stationary (0 energy and momentum). After inelastic collision C with A in a closed space we assume both objects move at velocity 5 m/s - momentum 10 kgm/s is conserved - and then we observe that the kinetic energy of A+C is only 25 J. Note that moving part C slowed down from 10 to 5 m/s in this inelastic collision! Where did the 25 J go? (In an elastic collision A gets velocity 10 m/s and C becomes stationary and no energy and momentum is lost).

If an inelastic collision really can take place in a closed, isolated space as suggested; mass C 1 kg/10 m/s/ 50 J/ 10 kgm/s hits stationary mass A 1 kg/0/0/0 and both (C+A) proceeds at 5 m/s (glued together?) after collision thus with constant momentum 10 kgm/s but only with 25 J kinetic energy, the missing 25 J energy evidently was transformed into, e.g. heat, deformations, failures of C and A at the inelastic collision. 12.5 J/kg kan really locally transform/modify C and/or A in many ways, but it depends on the structural and material properties of C and A.

The difference between an elastic and inelastic collision in closed space is that, in the latter, structure is modified and kinetic energy is transformed into heat. Momentum is always conserved.

Now lets study an example of the axiom. C is the smaller part and remains at 1 kg and A becomes the bigger part!

Let's say that A is 9 times bigger - 9 kg - than C and that C+A (10 kg) proceeds at only 1 m/s after collision/glued together in a closed space (momentum 10 kgm/s is conserved) and that you lose 45 J in the kollision or only 4.5 J/kg on A+C together. Note that moving part C now reduces speed from 10 to 1 m/s in order to transmit energy.

However, if the 45 J energy used to transform the objects is split 50/50 between C and A, then 22.5 J/kg is applied on small part C and only 2.5 J/kg is applied on big part A. Reason for this is that the contact forces between C and A are equal at contact.

In this case and, if C and A, has same structure/material/properties and are subject to identical forces, actually pressures or stresses, C breaks up long before A in an inelastic collision, as small C must absorb 9 times more energy than big A. The axiom suggests that similar things happens when two objects collide in an open space, where A may be fixed to, e.g. ground, e.g. like WTC 1 on 911.

It means that you cannot crush an isotropic or composite 3-D structure A by a part C of itself (C = 1/9 A) by dropping part C on A using gravity. Part C either bounces (elastic collision) on A or gets damaged (inelastic collision) in contact with A and is stopped by A that is also damaged a little. It is quite basic and all due to forces/pressures/energy applied and that the two parts have identical structure and material. Actual materials, size and particulars of the elements of the structure A doesn't matter the least. Part C of A cannot destroy A, as C must absorb much more energy per mass unit than A in the inelastic collision.

Thus no structures, 1, 2 or 5 meters tall, or 100, 200 or 500 meters tall exist that will one-way crush down, when a small part C is dropped on the bigger part A below.

And everytime a small, upper part C collides with a stationary big, lower part A, C loses most of its velocity and stops! If C does not lose velocity, as seen on 911, there is no collision at all! (It is a controlled demolition of some sort - C is destroyed first followed by A -from top down.)

However, various people, i.a. Bazant and Seffen, which will be further described below in parts I , III and V of this paper propose otherwise.

They suggest that what they describe as one-way crushing or progressive collapse takes place as follows: First, after impact, upper part C of a building A does not lose any velocity but increases it due gravity (!) and during the collapse there is a transfer of mass (?) from the stationary building, lower part A, to the moving top section, part C, due to deformation and local failures of structural elements in part A only - a layer of rubble, part B, attached to part C is formed, which is a function of displaced distance downwards. Second, the stationary building, lower part A, lamely resists the motion of the top, upper section, part C, and its rubble layer, part B, but cannot stop it. C and B just increase (!) their speed. After a few seconds the building C+A is just rubble B from top down. Or in other words; just drop a little piece C of a structure A you want to destroy on A and C destroys A.

The Bazant & Co crush-down theory applied to a structure consisting of five assemblies of structural elements - one upper part C and four lower parts A; All parts consists 95% of air. Each part has height h. Thus total structure has height 5 h.

(1) Lower parts A carries upper part C of the structure statically with a FoS >1 (actually >3 so that part C will not collapse by itself before start). Primary load bearing elements make up <1% of the structure volume. Upper part C is then dropped on top part A and one way crush-down, suggested by Bazant & Co, starts. The suggested reason is that upper part C can apply sufficient energy to destroy elements in part A and compress them into rubble part B without destroying itself. It is of course crazy! Part C cannot apply energy to destroy part A without destroying itself!

(2) POUFF!! Upper part C has crushed top part A into rubble part B A/4; The density of part B rubble is 4 times the density of C and A according Bazant. Part C has dropped 3/4 h. Part C remains intact according to Bazant & Co. In reality it cannot happen but Bazant & Co suggest otherwise!

(3) POUFF!! Upper part C has crushed two top parts A into rubble part B A/2; Part C has dropped 1.5 h! The rubble B assists the crushing of part A.

(4) POUFF!! Upper part C has crushed three top parts A into rubble part B 3A/4; Part C has dropped 2.25 h. The rubble B assists the crushing of part A.

(5) POUFF!! Upper part C has crushed all four parts A into rubble part B = one part A; Part C has dropped 3 h. The rubble B assists the crushing of part A.

(6) POUFF!! Rubble part B (!) has crushed up (?) upper part C into rubble from below. Parts A and C with density 0.25 have become 100% rubble of height 1.25 h and 'rubble' density 1.

(7) The rubble then spills out on the ground POUFF!!, according Bazant & Co (and is more compressed to density >1?).

Evidently no structure goes POUFF!! POUFF!! POUFF!! POUFF!! POUFF!! from top down when you drop a small top piece on it.

Fig. A7 - A building A with a top part C becomes rubble B due to progressive collapse and crush down of A by C according to false theories of Bazant and Seffen developed after 11 September 2001. Evidently a small top part cannot crush a bigger bottom part of same structure only due to gravity!

The basic errors with these suggestions are simply that no transfer of mass can occur between parts A and C due to a rubble layer, part B, being formed and accelerated and that part A evidently can arrest the motion of C in various ways. Bazant and Seffen are like the stalinist scientist (sic) Lyssenko in the 1930's. Their theories cannot be verified scientifically by laboratory and field experiments under controlled conditions; they just make up fantasy theories (to support terrorism!).

Actually, you can fly in as many planes as you like in the tops of WTC 1 and 2 but the lower structure of WTC 1 and 2 will not be crushed down by the tops ever! Structures like WTC 1 and 2 cannot collapse from top down! To destroy a structure you have to do it from bottom up (controlled/planned demolition) or step by step applying energy locally.

It is quite simple to learn what happens in collisions or impacts in open space or when different structures are really being crushed! Rule one is not to crush yourself by anything even if gravity alone will not suffice to crush anything completely. You have to check more! And stay alive.

Just drop Anything on Something

Start with a solid rubber ball, mass m (kg) and drop it on the floor from height h = 3.7 meters height = the height that WTC 1 upper part is assumed to drop. The ball free falls with acceleration g (9.81 m/s²) due to gravity, makes contact with the floor and normally bounces. The little ball was not rigid and deformed upon contact with the floor. Why? The strong floor applied a force on the solid rubber ball, so that it deformed, absorbed some of the kinetic energy E involved (E = m*h*g) and then released it and bounced up. Evidently the ball also applied a force on the floor that also deformed, absorbed the remainder of the energy involved; maybe the floor vibrated a little. This is Newton's third law at work. Note the change/direction of velocity of the ball!

Then do the same thing with a solid sphere of steel. Drop it on the floor. If the floor is strong enough, the same thing will happen as with a rubber ball! The steel sphere bounces. If the floor is not strong enough, i.e. it cannot produce a force big enough to deform the steel sphere, so that it bounces back, the floor will be damaged - a hole is formed in it, and the steel sphere drops through the hole at reduced speed and contacts something else below, or the floor is just partially damaged ... and catches the steel ball, i.e. arrests it. Note the the change of velocity of the sphere of steel.

Finally drop anything weak (an egg or a lemon?) on something strong! PLAFSH! The weak anything (the egg or lemon!) is crushed against the strong something! It's velocity becomes zero!

Don't forget that! This is what happens when different structures collide.

Try to compress a lemon with another lemon. What happens? Both lemons compress. This happens when identical structures collide.

Drop rubble on a structure and the structure doesn't collapse. Rubble cannot crush down any structure.

Now you have learnt a little what can happen when you drop anything on something and try to compress something. Contact forces develop temporarily and the velocity of the striking object changes! This basic knowledge is used in this paper.

And then you have to work from there. Do the analysis step by step! In A) a vertical drop, gravity is always at work and produces forces acting on the various parts in contact and you have to include that, in B) a horizontal collision, the propulsion force of the ship may still be active and you have to consider that.

When two bodies C and A of similar steel or any 3-D structure, isotropic or composite, but different size collide, both bodies C and A are evidently deformed due to contact forces at the common, contact, interface/damages area. Sometimes the bodies only bounce, sometimes they damage locally one another. Stronger structural elements in composite structures will affect weaker elements in both bodies, i.e. the weaker steel elements fail before the stronger ones. No rubble of steel elements is generally produced, when failures occur, as all elements, even broken ones, are still connected to other elements. Only rubble is damaged loose furniture and similar inside the steel structure and it is of no importance.

What is a Drop?

If the upper, 53 meters tall, 13-15 storeys upper part of WTC 1 above floor 97 actually dropped on the structure below is a matter of semantics. Drop suggests that it was not being held at all. I prefer that it came into contact after local structural failures and downward displacement and that it was prevented from dropping by the connecting elements between the two parts. Only the velocity at contact is of interest and it was not high in the WTC 1 case. Assuming a 'drop' of 3.7 metres, it does not produce a big velocity; it is around 8 m/s. If the 'drop' is dampened by intermediate connections the velocity is much less.

Assuming in A) above (WTC 1 upper part drops on the lower structure with perfect alignment columns/columns) that the two parts act as springs (disregarding local failures), the upper part would just bounce as described in one of my other articles. No global one-way collapse would ensue! This article is a follow-up of this conclusion.

In B) above (ships colliding or running aground like M/T Exxon Valdez) the contact velocity may be up to 10 m/s and the masses up to 200 000 tons, so it should be clear that in B) 8 times bigger momentums and 10 times more energies may be involved compared with A).

In order for an upper part of WTC 1 above floor 97 to drop on the structure below you must evidently remove all the supports below; in the WTC 1 case 47 core columns and four perimeter wall assemblies (each abt. 60 columns). What happens to the upper part of WTC 1, if you remove only one column below is shown in below figure of a different but similar structure:


Fig. A7 - A structure consists of elements and, if you remove one element at bottom, the elements above are affected, one after the other ... from bottom up! It means that the structure fails - collapses - from bottom up. The reverse is not possible!

Evidently the structural elements in the upper part, relying on one column below for support, will sag down, if your remove the support below. Reason is that the assembly of elements of the upper part above is not very strong. Same will happen, if the sole column fails for any reason.

When the upper part of WTC 1 dropped on 911, we are however told that all supporting columns suddenly failed (!) and that all structural elements of the upper part above displaced downwards as one intact, rigid, solid unit! And that this unit - the upper part - kept together! It was rigid! Solid! It could not deform! It acted as a hammer hitting a nail and produced one-way crushing of the structure (nail!) below! It has never happened before or after 911. No structure has ever been crushed down by a little, weak top part falling on the remainder structure before or after 911.
Part I - Prof. Bazant and NIST explain Something; One-way Crushing!

According Prof Bazant & al. [2] the following happens - one way crushing - when an upper part C, constant (sic) height z0, of WTC 1, total height H, above say floor 97, falls on the same structure, part A, below floor 97 and crushes floors 97-0, part A, into rubble, part B:

The gravity-driven progressive collapse of a tower consists of two phases—the crush-down, followed by crush-up (Fig. 2 bottom), each of which is governed by a different differential equation (Bazant and Verdure 2007, pp. 312-313). During the crush-down, the falling upper part of tower (C in Fig. 2 bottom (fig. 1 below)), having a compacted layer of debris at its bottom (zone B), is crushing the lower part (zone A) with negligible damage to itself. During the crush-up, the moving upper part C of tower is being crushed at bottom by the compacted debris B resting on the ground.

Or - first upper part C one-way down crushes part A top into a thin layer of debris B with thickness ls0 and then the complete part A into a thick layer of debris B with thickness l(H-z0) and then the thick layer of debris B up-crushes upper part C bottom into a thin layer of debris B' with thickness r=lr0 and then the complete part C into a thick layer of debris B' with thickness lz0 and then there is only a tick layer of debris B+B' with thickness lH left. l is the compaction ratio! Very nasty Greek letter! Apply it to any structure and l will compact it. First down, then up. And then there is nothing left but rubble!

It is very simple according Bazant [5}:

"When the upper floor crashes into the lower one, with a layer of rubble between them, the initial height h of the story (below) is reduced to lh, with l denoting the compaction ratio (in finite-strain theory, l is called the stretch). After that, the load can increase without bounds."

Nothing happens to the upper floor element or any other structural elements in upper part C! Its height z0 is constant! This is evidently impossible as we know from above that when two parts of identical structures come into contact in an impact, both parts are affected. One small part cannot transform a bigger part into dust, smoke and rubble ... and remain intact!

Fig. 1 - Figure 2 bottom from [2]



And:

Since the initial crush-up phase terminates at very small axial deformation, it must be concluded that the simplifying hypothesis of one-way crushing is perfectly justified and causes only an imperceptible difference in results.

This new phenomenon one-way crushing of a 3-D structure has never taken place before and after 9/11 as it is physically impossible! Note no mention of forces! So how could one-way crushing of a 3-D structure suddenly occur on 9/11? Check again photos above!

NIST has slightly different description of the one-way crushing down of part A by upper part C! From NIST report - NIST NCSTAR 1-6D chapter 5.2:

"The aircraft impacted the north wall of WTC 1 at 8:46 a.m. … between Floor 93 and Floor 98. … The subsequent fires weakened structural subsystems, including the core columns, floors and exterior walls. The core displaced downward … At 100 min (at 10:28:18), the north, east, and west walls at Floor 98 carried 7 percent, 35 percent and 30 percent more gravity load loads … and the south wall and the core carried about 7 percent and 20 percent less loads, respectively., … At 10.28 a.m., 102 min after the aircraft impact, WTC1 began to collapse. … The release of potential energy (PE) due to downward movement of the building mass above the buckled columns exceeded the strain energy (SE) that could be absorbed by the structure. Global collapse ensued."

However - repeat - when two bodies C and A of identical or similar steel or any 3-D structure but different size collide, both bodies are evidently deformed due to forces and energy applied at the common contact, interface area. Sometimes they only bounce, sometimes they damage locally one another. Stronger structural elements will affect weaker structural elements in both bodies, i.e. the weaker steel elements fail before the stronger ones.

The upper part can only apply forces/energy limited to its own strength and then it will break up. No one-way crushing can take place! No rubble of steel elements is generally produced, when failures occur, as all elements, even broken ones, are still connected to other elements. Only rubble is damaged furniture and similar inside the steel structure and it is of no importance.

A smaller part C of a structure cannot crush down a bigger part A of the same structure assisted only by gravity. No global collapse can ensue for that reason!

Just watch the videos of the destruction

The global collapse (sic!) or one-way crushing that ensued at WTC 1 can be seen here! Or just the start of it, the collision of the upper part C with the lower structure here as also shown below on two snap shots - fig. 2. You can slide the video fwd/aft and see how the upper part C is destroyed first, while everything below remains intact as shown below - there is no impact or collision:

Fig. 2 - Upper part C is destroyed!

The upper part C of WTC 1 is above the yellow lines applied on the photos (from Internet - reliability not guaranteed) of the WTC 1 tower at say floor 95 and the lower structure is below. Snap shot left above (fig. 2) is just before destruction of upper part C starts and snap shot right a few seconds later. It should be clear to anybody that the upper part C above the yellow lines simply disappears in the smoke and dust, while nothing has happened to the lower structure of WTC 1.

The aircraft impact point in the North Tower was between the 95th (yellow lines) and 96th floors with the aircraft nosed down at 10 degrees, but the North Tower collapse initiates 30 feet above at the 98th floor, where there was very little aircraft impact damage.

The first floors to collapse afterward are the 99th through the 102nd, which in addition to having no aircraft impact damage had little fire if any. In other words intact structure above the aircraft impact zone and main fire affected areas is actually collapsing first.

These observations alone should make it clear that the building was demolished and that the aircraft impacts were a cover for the demolitions to allow the collapses to be blamed on outsiders.

Evidently gravity alone cannot destroy, shorten, the upper part C before it, the upper part C is supposed to impact and collide with and crush down WTC 1 below!

Why is there so much smoke, debris and vertical deformation of the upper part C only?

It, the upper part C, is simply destroyed by some energetic material devices and there is no collision with the lower part. Same devices are apparently used to destroy the lower structure of WTC 1 a few seconds later. In the official accounts of the destruction of WTC 1 the upper part C is supposed to remain intact - its height z0 is assumed constant - and produce one-way crushing until the end of destruction and be crushed against the ground.

Rigid Blocks, Boxes or Sponges

NIST speaks of the core of WTC 1 as consisting of three sections - NIST NCSTAR 1, p. 79:

"At this point, the core of WTC 1 could be imagined (sic) to be in three sections. There was a bottom section below the impact floors (i.e. below floor 93) that could be thought of as a strong, rigid box, structurally undamaged and at almost normal temperatures. There was a top section (the upper part C above floor 97) above the impact and fire floors that was also a heavy, rigid box. In the middle was the third section, partially damaged by the aircraft and weakened by heat from the fires."

The section of the building above the damage zone, the upper part C, NIST calls a "rigid box."

This rigid box first manifests its independent movement, when it tilts to the south - NIST NCSTAR 1, p. 201: "The section of the building above the impact zone (near the 96th floor), acting as a rigid block, tilted…". Do you see that on photos above?

NIST also refers to this rigid block or box with terms such as "upper section", "building section above the impact zone", "building mass", "upper building section" and "structural block." - NIST NCSTAR 1, pp. 83, 195, 196, 201.

However, you have to treat the upper part C structure/stiffness in 3-D and then it becomes very springy - like a sponge; light structure of elastic material full of holes. It is quite difficult to destroy a sponge dropping another sponge on it. The other sponge bounces.

NIST acknowledges that this rigid block or box, upper part C, then falls. NIST says that "the building section began to fall downward", "the building section began to fall vertically". Do you see that on photos above?

It is suggested that this falling rigid block goes through all or part of the damaged area or initiation zone "essentially in free fall" : "Since the stories below the level of collapse initiation provided little resistance (sic) to the tremendous (sic) energy released by the falling building mass, the building section above came down essentially in free fall, as seen in videos" - NIST NCSTAR 1-6, pp. 416, 238; NIST NCSTAR 1, p. 196. Do you see that on photos above?

And seen in videos? Where? None of above is seen anywhere!

After falling through all or part of the damaged area of WTC 1, the rigid block or falling building mass - the upper part C - encounters "intact structure". And, no surprise: "The potential energy released by the downward movement of the large building mass far exceeded (sic) the capacity of the intact structure below to absorb that through energy of deformation." - NIST NCSTAR 1, p. 196. This is very strange! The intact structure was previously described as a rigid box! And there is no evidence for the suggestion!

Energy of deformation is the same as strain energy!

What is Strain Energy and can you calculate it?

Strain energy (SE) is simply speaking a measure of the strength of the elements of the structure that holds it together and can resist deformation and damage. Apply outside energy (force times displacement) on the structure that exceeds the strain energy that can be absorbed and the structure deforms or an element fails locally. If it fails, it fails in the highest stressed area only and the structure changes! Evidently the strain energy of the structure at every floor above, the upper part C, and in the structure below the initiation zone was about the same. However, in all official explanations of the collapses it is assumed that the upper part C is rigid with height z0 is constant and infinite strain energy from start and therefore will not deform and will absorb no amounts of extra strain energy at all! All free energy (or forces!) at impact is therefore assumed being directed down (?) into the lower non-rigid structure by NIST and its supporting experts. No forces are directed upwards!

The upper part C is however not rigid and can only absorb very limited strain energy during a crush down prior it self-destructs to forces acting on it and the destruction is arrested. To assume the opposite in various papers described below and indirectly by NIST is simply to mislead the public. The upper part C has a very limited capability to absorb strain energy - it will get destroyed - and that is the main reason why it cannot crush down the structure below and produce rubble. On the contrary - the upper part C structure should be subject to serious structural failures at impact and absorb the energy released and arrest further destruction. Not so difficult to grasp. That's why steel buildings of any type are not crushed down one-way by gravity acting on a loose top part due to local failures of some elements.

Every time you break an element of a structure, strain energy is consumed. The amount of strain energy built into a structure thus depends on how many times you break the elements. The amount of potential energy, PE, due to downward movement of the WTC 1 upper part C mass was definitely too small to destroy the lower structure in 100.000's of pieces and dust. There is 1 000 times more strain energy, SE, built into the structure below than any gravity PE applied from above! Calculations are given below and here.

Prof Bazant (further described below) and NIST suggest that the energy initiating or released at the WTC 1 destruction was enormous but in a serious ship collision it can be up to 10 times bigger and still the local failures are limited!! NIST should learn from ship collisions!

Bazant, like NIST, also assumes that the WTC 1 upper part C was rigid (!). Its height z0 is constant! A rigid object is indestructible and will destroy anything non-rigid. But ships and WTC 1 upper part C structures are not rigid and break up at impact or collisions (unless they just bounce) due to local forces developing.

The structural damage analysis are quite similar for A) and B). Very few mechanical, civil or building engineers have studied the subject (99.9% concentrate on design of new, intact structures) but there is nothing new about structural damage analysis [4]. No need to write scientific papers about it, as it was a new event that had never happened before and needed explanation. Structural damages (ship collisions) occur every day. Steel structure tower collapses are much more rarer.

The Bazant papers described below are therefore very suspect. Enjoy this article. Comments are always welcome. And thanks for comments already given.

Fig. 3 - North and West (right) walls of WTC 1 just prior destruction. According basic structural analysis no failed parts of the upper part C can damage the solid columns below the initiation zone. This is the beauty of steel structure design. If a part fails and loads are displaced by gravity, only secondary, weaker parts may fail (mostly floors) as a consequence. The intact primary structure below cannot fail!


The official Explanation(s) - One-way Crushing

The official NIST explanation(s) of the WTC 1 (fig. 3 left) global collapse (sic - should be crushing) is that the alleged release of potential energy (PE), of the mass of an upper part C above all supporting columns after sudden, local deformation and buckling, due to downward, alleged near free fall movement in an initiation zone (indicated by red) and impact of a structure below, exceeds the strain energy (SE) that can be absorbed by the same columns below and above and that all this was due to gravity only.

It is suggested that the upper part C is rigid and remains intact during the complete one-way crush down of the WTC 1 structure below, i.e. the global collapse (sic) is not a collapse but a 'one way crush down'.

The one-way crush down is suggested to take place as follows (fig. 4):

WTC 1 is assumed to consist of three parts:

Fig. 4 - Schematics of a crush down of WTC1 on 9/11 by rubble!


Part A - the lower structure (yellow in the picture) (97 stories before crush down); it is a non-rigid structure!

Part C - the upper part (13-15 stories): it is assumed rigid during crush down - its height z0 is constant - and is thus completely different from part A (and that is the key to the NIST falsifications!)

Part B - rubble that is formed of part A due to lack of strain energy, when rigid part C crushes the stories one after the other. Part B consists of small pieces of what was upper part A - rubble!

Each storey is 3.6 meters tall with uniform density 0.255 and becomes a 0.9 meter thick layer of rubble with uniform density 1.025, when crushed [2].

At time t = 0 sec part C is alleged to drop on part A - one-way crush down or rubble production starts.

At, say, time t = 10 seconds about 60 stories have been crushed and there are still 37 stories remaining of part A. A 54 meters thick layer of rubble - part B - has been formed of what was 60 stories! The upper part C remains intact on top.

At time t = 12 seconds part A is completely crushed and only a 87.3 meters thick - very tall! - layer of rubble on the ground - part B - remains of part A. The upper part C still remains on top.

At time t = 15 seconds nothing remains! Part C has suddenly become non-rigid and has been destroyed in a one-way crush up and the rubble - part B - is spread out on the ground.


Fig. 5 - Schematics of local failures up top of WTC1


Evidently this crush down model and theory is complete nonsense, but it is the official explanation(s) of the WTC 1 destruction on 9/11! A small, fairly weak upper part C, 95% air, cannot possibly crush a big part A of similar structure only due to gravity and compress it into a 87.3 meters tall tower of rubble on the ground after 10 seconds!

If weak upper part C actually dropped, it would get locally damaged at its bottom and there would be some local damages to part A upper part. The worst case is that weak upper part C is completely destroyed and part A is locally damaged at top. Rubble part B would only be formed on top of part A and part C would be rubble. And rubble cannot crush anything! Fig. 5.

Anyone that has just dropped anything on something knows this. Try then to crush this something! You need a big force that displaces (energy) for that, which gravity alone cannot provide. Only when NIST assumes that upper part C is rigid during one-way crush down and does not become rubble itself and suddenly becomes non-rigid during crush up, NIST can manage to get their fantasies together.

What you would expect to happen

The following would happen, if the upper part C actually drops; two of its thin but strong walls slide and drop outside and do not damage anything. The other two thin but strong walls slide and fall inside the structure - part A - below and punch holes in or slices the thin, weak floors there locally. No rubble is really formed.

The thin, weak floors of the upper part C are in turn locally punched or sliced by the part A strong walls/columns below and will soon be jammed inside the part A walls/columns below. No walls or columns are dropping on other walls or columns producing an impact! Do not believe that the upper part C is solid, rigid, strong or anything like that! It is quite weak. Local failures - weak floors punched and sliced - will be produced at contacts. No crush down will ever start!

Local gravity failures above cannot destroy the steel columns of the intact structure below! All the energy released by dropping upper part C and applying forces is absorbed by the deformations, failures and fractures of thin floors in the initiation zone and locally in the upper part C and top of lower structure part A and by friction between locally failed floor parts rubbing against each other after initiation and by any loose parts dropping down outside. The crush down or local failures should be arrested inside the initiation zone!

Controlled Top-Down Demolition - Big Sheets of intact Perimeter Wall Columns assemblies would be pushed out and drop to Ground!

One way of demolishing a structure is to horizontally cut off vital connections of primary structure holding the structure together at the bottom, i.e. to reduce its strain energy in its strongest elements. The structure above will then drop straight down due to gravity and be damaged. It is called Controlled Demolition! You can try the same thing starting from the top, cutting structure horizontally up top!, but then you will create a fountain of rubble, when blowing broken structure sideways. See figure 22. Gravity only failures without further assistance do not produce rubble. Controlled demolition on the contrary produces plenty of rubble in the process of destruction.

To demolish WTC 1 with controlled demolition is very simple. As 37.4% of the total mass of the tower is carried by only 24 outer, albeit very strong, core columns of various thickness, it would appear that by cutting them at say 10 floors intervals, load transfers to the perimeter walls would break the walls and the tower would come down. Big sheets of intact perimeter wall columns assemblies, 10 floors high, would then be pushed out and drop to ground! You can see it on all videos of the destructions.

Access to these outer core columns appears very easy. How to quickly cut a 25 mm plate at very low cost is explained here. Similar devices can probably cut steel columns.

[quote]Part II - The major NIST Problem - Lack of Evidence!

The major problems with the NIST cause - a one-way crush down from top to bottom - are that fires normally only cause visible, local structural failures, deformations, fractures and displacements of steel structure elements that are soon arrested, when any energy released is absorbed by intact structure above and below the contact points and local failures - no global collapse or rubble . There is

(1) no evidence that the core structure displaced downward, as it could not be seen,

(2) no evidence of any simultaneously buckled visible, outside wall columns in the fire zone - no such damaged, buckled, columns have been retrieved from the rubble;

(3) no sign (evidence) of drop of the building mass above the buckled columns - the upper part C - at near free fall acceleration a certain height and time as a rigid, solid mass and associated release of potential energy, PE, and

(4) no indication (evidence) of an impact (the PE is now kinetic energy, KE) between the rigid, upper part C and the non-rigid structure below at which perfect alignment is necessary, which would be seen as a bump/deceleration on any video.

These four conditions are according NIST required for the upper part C to commence destroying, crushing down, the structure below, but there is no evidence for them. Evidence to the contrary will be produced below.

The upper part C is not really one part. It is a steel structure and an assembly of elements; columns and floors.

There is further

(5) no calculations by NIST of the potential energy, PE, released and the strain energy, SE, or lack of it, of the structure below (and above!) that could be absorbed proving it was less than the PE or KE transmitted to it by the upper part C permitting a gravity only driven global collapse/one-way crush down to progress or ensue,

(6) no mention or calculation of forces, deformations, fractures in and friction between locally and partly damaged floors and other elements that would absorb further energy after initiation,

(7) no explanation how the solid, intact columns below were overloaded by gravity only, what loads were actually applied on the columns after initiation and why the columns would rupture/fracture horizontally in 1 000's of pieces about 10-12 meters long,

(8) no explanation (or evidence) why the upper part C would remain intact at the (4) impact (except that it is rigid, which it is not), and

(9) no explanation why so much rubble (broken, fractured elements), smoke and dust were produced.

Evidently the potential energy released is transmitted to both the upper part C structure and the structure below - always as walls/columns punching/slicing floors - a fact that NIST conveniently forgets or ignores or intentionally censors. Actually 50% of any energy released should be absorbed by the smaller upper part C floors at impact and following deformation and local structural failures.

Evidence contradicting the NIST Cause

All videos of the WTC 1 destruction show that the upper part C telescopes into or shortens itself or implodes for about 3-4 seconds (like the bottom structure below floor 16 of WTC 7 10 hours later), while the steel columns of the structure below are still intact prior any invisible impact! Gordon Ross has described this clearly 2007. The deformation of the upper part C cannot be produced by gravity forces alone. The upper part C is not very strong and you wonder how it can crush down anything - except itself - later? David Chandler explains clearly what happens in his video analysis 2009.

It would appear (fig. 6) that the WTC 1 roof line drops about 35 meters in 3.1 seconds at an average velocity of 11.3 m/s prior any destruction of structure below is initiated (by an alleged impact). The acceleration associated with such a drop of the upper part C is of the order 7.3 m/s² or 0.75 g, and this displacement of the roof line is not associated with any destruction of structure or floors below floor 93! The only conclusion is that the upper part C, undamaged by any real fire, is compressed/implodes vertically >50% during the 3.1 seconds ... and there is no impact! This vertical compression is however not associated with any horizontal expansion of the structure of the upper part C, so how can it take place? At least 8-10 floors of the upper part C including the initiation zone seem to disappear prior any destruction of the structure below.

One explanation is that the columns between a fair number of floors inside the upper part C are locally destroyed or cut and displaced prior initiation of lower structure destruction. The ejection of smoke from the upper part C prior any destruction of structure/floors below suggests that some form local destruction is taking place in the upper part C.


Fig. 6 - from [2] by Bazant
It has been suggested that the local destruction of the upper part C starts on the 105th (!) floor as seen on videos (reliability not guaranteed) of the South wall of the North Tower/WTC1 - sudden fire, where there was no fire before, and some wall columns buckling.

Fig. 7 A - WTC 1 North wall just before upper part C roof line starts to drop. Note intact steel columns below the upper part C bottom floor #97. No collapse or crush down of structure below has yet started there due to lack of strain energy ... and it will not take place! As soon as upper part C drops, rubble should be produced below it!


Fig. 7 B - WTC 1 when upper part C roof line has dropped abt 15 meters after about 2 seconds of roof line dropping. Total 5-6 floors (floors #97-92/91) of Lower part A should have been crushed and replaced by a 5 meters thick rubble part B acording [2]. But lower part A has not been crushed down 20 meters and no 5 meters rubble layer part B is visible. Lower Part A still extends to the red line.


Fig. 7 C - WTC 1 when upper part C roof line has dropped abt 35 meters after about 3.1 seconds of roof line dropping. Total almost 13 floors (floors #97-84) or 46.7 meters of Lower part A should have been crushed and replaced by an 11.7 meters thick rubble part B acording [2]. Lower Part A still however extends to the red line. No collapse/crush down of lower part A below has started and there is no rubble part B!
Soon after the upper part C disappers completely in a cloud of smoke and rubble! A big, 7 floors tall piece of the West wall with 25 wall columns and seven spandrels between floors, say #99-106, i.e. 25 x 25 meters, weight more than 100 tons, is seen to be ejected outwards at high speed in the fountain of rubble. It leads the rubble, i.e. is the first part of the upper part C to be detached. Evidently such destruction cannot take place by gravity and an intact (!) upper part C crushing down.
http://heiwaco.tripod.com/WTCxx.jpg
Fig. 1 - Figure 2 bottom from [2]

According Bazant [2] upper part C shall be 100% intact during these 3.1 seconds (and later of course) and produce an 11.7 meters rubble layer and destruction shall only take place below it and the rubble part. No destruction can take place above the rubble part, where upper part C shall remain intact!

What we are really seeing on above three pictures (fig. 7 A, B and C) is local destruction of both parts A and C and not a one-way crush down of part A by an intact part C producing rubble. In above picture right (fig. 7 C) it is obvious that the upper part C is being destroyed just after initiation of destruction and that there is no rubble below. No smoke and debris shall be expelled from an undamaged upper part C structure.

There are 1 000's of photos of the crush down that follows but unfortunately some are missing, e.g. those during the 0.8 - 0.9 seconds, when the alleged indestructible upper part C supposedly near free falls 3.7 meters - all columns fail there and disappear at one storey - and then collides/impacts with the structure below transmitting the total upper block KE.

Actually no such photos exist as no free fall or impact took place! And no intact upper part C is seen during the crush down destruction of the structure below that follows. The upper part C was simply destroyed prior to any impact.

The upper part C of WTC 1 is a problem for NIST. Its weight was not massive, only about 33 000 tons and the uniform density was <0.18! It consisted of 95% air. The load bearing columns - the primary structure carrying this weight - occupied only 0.13% of the total foot print or floor area in the initiation zone - the rest was air, floors and furniture, which is an indication how strong the lower steel structure columns were! The compressive static forces and associated stresses in the steel columns were low; <32% of the yield stress, i.e. a Factor of Safety, FoS, of elements against yield more than 3. And the built in strain energy, strength, to keep the upper part C together was exactly the same as for the structure below.



Part III - What is a One-way Crush down? Ever heard about one?

The American professor Z P Bazant, already mentioned above, published (13 September 2001) soon (2 days only!) after the WTC destructions an early explanation of his ostensible and passionate theory [1] that was adopted by the authorities, FEMA and NIST, as true. Bazant suggested that there were five stages until the doom/one-way total crush down of a structure as illustrated in Fig. 8.

Stage 1: The fire causes the steel of the columns to be exposed to sustained temperatures apparently exceeding 800° C in an initiation zone (500° C according NIST - and in only a few columns at a time).

Stage 2: At such temperatures, structural steel suffers a decrease of yield strength and loses its load carrying capacity! (Actually the load carrying capacity is reduced abt 20% at 500°C and with a Factor of Safety >3 no serious decrease of load carrying capacity should happen).

Stage 3 (One-way crush down starts): Once more than half of the columns in the critical floor (floors 94-95 of WTC1) that is heated most suffer buckling so the upper part starts falling down onto the structure below the critical floor (floor 93). At that moment, the upper part has acquired an enormous kinetic energy, KE,(only 1.2 GJ corresponding to 41 kgs of jet fuel - if it actually happened) and a significant downward velocity (less than 9 m/s)!


Fig. 8 - Figure 1 from [1]

Stage 4 (First one-way crush): The vertical impact of the mass of the upper part onto the structure below applies enormous vertical dynamic load on the underlying structure below, far exceeding its load capacity, even though it is not heated. (Actually 50% of the energy (the dynamic load) is transmitted to the upper part, if an impact and visible deceleration of the upper part would have taken place, and the upper part would have been destroyed very quickly; compare the rubber ball bouncing on a floor described above).

Stage 5 (Compression and more one-way crushing): This causes failure of an underlying multi-floor segment of the tower, in which the failure of the connections of the floor-carrying trusses to the columns is either accompanied or quickly followed by buckling of the core columns and overall buckling of the wall columns! (Not proven, of course. The upper part should simply bounce on the lower structure, while there are some local failures. Just buckling one column requires; first to deform it elastically vertically and sideways, then to produce three plastic hinges in the column, then to produce fractures in the hinges that must cut through the column; as soon as one fracture cuts off the column, there is no longer any contact and the top part slides off the lower part, etc).

Stage 6 (One-way crush down): The part of building lying beneath, i.e. the structure below, is then impacted again by an even larger mass falling with a greater velocity and the series of impacts and failures then proceeds all the way down (This is impossible! Each column has now been cut off by one fracture at one plastic hinge and the upper part of a column can no longer impact a lower column. It will therefore contact something else - a floor! - and cause local failure there or just slide against other structure. Friction between loose parts absorbing energy should now start).

This Stage 6 is the famous 'one-way crush down' of a 3-D steel structure that nobody in serious structural engineering circles had ever heard of before 911, when it was invented by Bazant. Or after! Compare with the global collapse (sic!) that ensued that can be seen here!

In [5] Bazant (2007) points out errors in his previous paper and develops some new ideas about Stage 6:

"The kinetic energy of the top part of the tower impacting (sic - highlight by AB) the floor below was found to be about 8.4X larger than the plastic energy absorption capability of the underlying storey, and considerably higher than that if fracturing were taken into account. This fact, along with the fact that during the progressive collapse of underlying stories … the loss of gravitational potential per story is much greater than the energy dissipated per story, was sufficient for Bazant and Zhou to conclude, purely on energy grounds, that the tower was doomed once the top part of the tower dropped through the height of one story or even 0.5 m. It was also observed that this conclusion made any calculations of the dynamics of progressive collapse after the first single-story drop of upper part superfluous."

and

"When the upper floor crashes into the lower one, with a layer of rubble between them, the initial height h of the story is reduced to lh, with l denoting the compaction ratio (in finite-strain theory, l is called the stretch). After that, the load can increase without bounds."

Does really the kinetic energy of the upper part C after a drop of only 0.5 m exceed the plastic energy absorption capability of the underlying storey and by a factor of 8.4, if the drop is 3.6 m, and is it relevant? Well, the upper part C is 53 meters tall and an underlying storey is only 3.6 meters tall and if you assume that the upper part C is like a solid hammer head and the underlying storey is a nail, then the hammer head will deform the nail. But no rubble will be produced. The hammer head, the upper part C will then slip off. Bazant assumes it hits again. To produce rubble you must hammer several times, repeatedly.

If, one the other hand you assume that the nail consists of 97 storeys, i.e. consider the whole structure below, then the underlying structure can elastically absorb 97 times more energy than just one storey and then the upper part will just bounce on the lower structure. The kinetic energy of the upper part C is just 0.086 of the plastic absorption capability of the total structure. And let's face it - the upper part C is not a solid like a hammer head! It is as flexible as the lower structure and will absorb 50% of the energy applied at alleged impact.

The kinetic energy of the upper part C was too small to do any real harm or initiate a crush down. The only result will be lots of local failures up top.

The upper part C of the tower cannot really impact the floor below, because, before that would happen, the intermediate columns ends damage locally both the floor above in the upper part C and the floor below (the underlying storey) and the interface changes. No rubble is really created except crushed furniture and lightweight walls (gypsum boards) as the space between the top part and the underlying floor is 95% air - the columns occupying 0.13% of the volume.

Upper Part C is destroyed by Forces acting on it

It is furthermore not the total kinetic energy of the upper part C that is applied to the underlying storey - only the forces applied by upper part C columns are locally damaging, fracturing the underlying floor. At the same time the columns below apply forces on and start to destroy the upper part C bottom floor in the same manner. To fracture, punch through or slice a floor requires energy. Locally damaged floors would then get entangled into one another, huge friction forces would develop and arrest further destruction. No impact! To suggest that the load can increase without bounds due to a layer of rubble is nonsense. Bazant ignores local damages to the floors, all fractures that develop and the huge friction between these locally failed floors as the main factors arresting structural destruction. The loads and forces are actually reduced, mostly by friction! And collapse arrest should soon follow!

Obvious Contradictions

Regardless - Bazant 100% contradicts what NIST says about the system that supports the upper part C (repeat from above):

"The subsequent fires weakened structural subsystems, including the core columns, floors and exterior walls. The core displaced downward … At 100 min (at 10:28:18), the north, east, and west walls at Floor 98 carried 7 percent, 35 percent and 30 percent more gravity load loads … and the south wall and the core carried about 7 percent and 20 percent less loads, respectively., …." (NIST report - NIST NCSTAR 1-6D chapter 5.2).

Imagine an upper part C supported by a core and four walls and that the core below it (not seen of course) displaces downwards! Then the core cannot support anything above, unless the upper part C starts to deform, but why should it? It is undamaged. So, if the core displaced downwards as suggested by NIST, the core would then carry 100% (!) less load, i.e. nothing at all; actually the core must have been disconnected from the upper part C and the load on the core should be transmitted to the walls.

Furthermore, Bazant assumes in [1] that the lower structure can be regarded as a spring (while the upper part C is rigid and not a spring at all!) and wonders what its spring constant C can be:

"According to this hypothesis, one may estimate that C =71 GN/m (due to unavailability of precise data, an approximate design of column cross sections had to be carried out for this purpose)".

This results in an extremely stiff spring that does not really compress at all as a spring (more like a solid rod) and is easily locally overloaded, i.e. breaks in one point (at the top) but does not globally collapse. But if a big force, or 4F in figure below, would suddenly be applied to the top of a lower tower structure with flexible vertical columns supported by horizontal floors pin joint to the columns by an upper part from above (let's forget that the core has already displaced downwards), you would expect the whole lower tower structure to deform as shown below in fig. 9, i.e. bulge in/out between floors, before any failures occur! Simple Finite Element Analysis, FEA, or rather beam analysis shows this. The forces are evidently balanced by reaction forces at ground supports and the energy E applied to the structure, now stored as elastic compression d, is simply E = 4 F d.
http:
Fig. 9 - Elastic, vertical deformation of of steel beam tower

The WTC 1 and 2 Towers were flexible

The WTC towers were in fact very flexible. Apply a very strong wind load sideways and the roof may deflect transversely 2-3 meters relative the ground. When the plane suddenly impacted horizontally at floors 95-96, the whole WTC 1 tower must have been displaced sideways (south) at least 1 meter or more there and then have been swinging back to vertical and 1 meter or more in the opposite (north) direction in say 10 seconds and more at roof level. The mast on top must have been swaying a lot. People in the top floors should have been thrown into walls and furniture or on the floor due such a big, sudden impact from the side. Wind loads are less sudden but must have been felt earlier in the history of the building. Wave impacts on ships are described here. WTC 2 was impacted lower down and would only displace sideways (north) 0.5 meter at floor 77, then back to vertical and 0.5 meter backwards (south) but more higher up. Total displacement between extremes is >1 meter, which should be seen on any video, e.g. the Scott Meyers video of the west and east walls (distance between wall columns is 1 meter and maybe you will see them swaying? The author could not!) The tower would be oscillating for one or two minutes after impact and NIST has apparently analysed that. So much for transverse flexibility.

Regarding the lateral impact - e.g. an aluminium wing structure, the ax, chopping through a steel box wall column, the log - the pressure between aluminium and steel parts and energy applied at a very small contact area at high velocity (>200 m/s) must have been extreme causing high temperatures virtually melting the metal instead of fracturing it. The chop must have taken <0.002 seconds! The wing is then destroyed and cannot chop, e.g. internal steel core columns! However, the vertical impact later, upper part C dropping by gravity on part A, should have taken place at much lower velocity allowing the structures to deform.

A realistic value for WTC 1 as a vertical spring - vertical flexibility- being suddenly loaded from above is C = 0.5-1.0 GN/m at top and little more further down, the lower structure is also quite flexible, and then the upper part C should just bounce [6] on the lower structure at hypothetical impact disregarding local failures at contact points. You should in fact be able to see a big compression of the lower part A, if the upper part C actually impacted and then local failures would follow.You wonder why Bazant estimates spring constants 140 times bigger than a realistic one and that the upper part C remains intact and no elastic deformation of the lower part. To prove global collapse? His whole theory seems to be based on this estimate. However, David B. Benson, co-author of [2] with Bazant has 27 January 2009 explained to the this author:

"That result applies, strictly speaking, only to a one-dimensional homogenous crush down. Since the top portion was tilted and the sturcture (sic) was not homogeneous, no damage to the top portion is only an approximation to reality."

http://heiwaco.tripod.com/nist3.htm

[rsol]

wow iso big (but excellent) post

ill counter jazz wih a shorter reply

"Jet Fuel Doesn't Get Hot Enough to Melt Steel"
For the umpteenth time, nobody ever claimed the steel melted. It got hot enough to lose its strength.""

misdirected. even mayor giuliani talked of molten steel under the towers.

"like a foundry" was a description by a firefighter on the scene. you only have to look.

The issue of whether the steel softened or melted causing the "collapse" is a non-issue and merely a distraction from the fact that molten metal was under those sites. Im not talking of a few pictures. im talking about foremen warning their men not to hose an area because of the steam it would cause.

THE POINT..... was that molten metal was discovered down there....official denial or not.

KEROSENE WILL NOT MELT STEEL!!!

Check the surface temps taken by nasa on the day. WAAAAAYYYY too hot to be two mostly burnt out fires. The fact that WTC7 had a hot spot under it is telling too........

[video=googlevideo]http://video.google.com/videoplay?docid=545886459853896774#[/video]
Throw any excuse you like at it, oxygen generators was my fave
They keep on insisting that aluminium glows when its hot

[nik]

nice one, icosa

---

(08-29-2010 10:22 PM)JazzRoc Wrote:  Good luck, Nik.)

Thanks

[icosaface]

Here is the rest of the analysis begun in the previous post.

Quote:The WTC1 destruction is evidently not a one-dimensional homogeneous one-way crush down of a homogenous rod and approximations should be avoided.

David B. Benson has also informed he has seen no videos and pictures of WTC 1!! His PC is too slow!

If any column would fail and not produce a bounce before that - Stage 2 in the Bazant theory - you would expect the following to happen to it in 3-D, when a compressive load is applied:


Fig. 10 - Five steps of buckling of a column due to vertical, compressive load

First, A, a plastic hinge develops in the middle of the compressed column due to lack of strain energy there, then, B, two more plastic hinges develop above and below the first hinge, then, C and D, the column 'kneels' and finally, E, a severely deformed part of the column may punch a hole in the floor below it. The column will never fracture in any location and it will never rupture due to fractures at the hinges into several pieces, i.e. it will always be connected, albeit very deformed. To suggest that 'buckling' of a column will result in free fall of the load it carries is not correct! The above deformation takes time and would be seen on any video, if it took place! Thus, Stage 3, of Bazant in not possible! It is an invention!



Part IV - Strange Explanations and real Verifications

More strange explanations/inventions were given by Bazant (2008) in [2] with Frank Greening and David B. Benson joining.

In [2] WTC 1 is split into three parts during destruction; part A - lower structure to be crushed, part B - a layer of rubble being formed by a part C - the upper part - that remains intact and drives the destruction.
Mass and Density of Part C

Near the top, the linear, 1-D, specific mass (of WTC 1) (mass per unit height) µ = 1 020 000 kg/m or 1 020 ton/m according [2]. In [2] the problem is only in 1-D; one dimension! A line with point masses that is being shortened!

With a storey height 3.6 m, the mass of a storey - or the line representing the storey - is 3 672 ton. Assuming the upper part C is 53 m high (14.7 storeys), total mass of upper part C is 54.060 tons. In article the author suggests 33 000 tons, but the difference is of no importance.

Using a floor area of 4 000 m² of the line - to make the model 3-D - the volume of upper part C is 212 000 m3, thus the uniform (which it is not) density of the upper part C is 0.255 ton/m3 or 255 kg/m3 according [2]. It is not very much! Reason is that there is plenty of air inside a storey 3-D structure.

This clearly shows how Bazant & Co confuse the issue: they treat the three parts A, B and C in 1-D as lines!

Density of Rubble - Part B

The known typical (sic) linear, 1-D, density (sic) of rubble, µc = 4 100 000 kg/m or 4 100 ton/m according [2]. The density of this rubble is then exactly 1 025 kg/m3 (as the floor area is 4 000 m²), which is the density of salt water (that ships float in). Imagine a line of salt water!

Fig. 4 - Schematics of a crush down of WTC1 on 9/11 by rubble!

Thus, when one storey is homogeneously crushed, it becomes 0.896 m high. As it was originally 3.6 m high it has been compressed 75.1%. What type of line can be shorthened 75.1%?

In real collisions between similar structures no part B - rubble - is ever formed! Only parts A and C are locally damaged at the contact area! Bazant & Co just invent part B to hide this fact!

Initiation of Collapse - the first Crush - Formation of Part B

Thus at initiation – upper part C – 54 060 tons – crushes the uppermost floor - say it is floor no. 96 - of part A, the lower structure of WTC 1, and compresses it into a 0.9 m thick layer of debris that becomes part B. This layer is resting on the second uppermost floor of part A. This compression takes place at increasing velocity. Only air/smoke is ejected sideways out between floors 96/95. The mass of the rubble - 3 670 tons - is uniformly distributed on the floor no. 95 below - 918 kg/m² - and this floor no. 95 floor should be able to carry that load according NIST FAQ.

Note that part C only compresses the storey floors 96/95 into a rubble layer - part B. It does not accelerate the rubble layer/part B. No solid parts are ejected sideways. The compression should be associated with a noticable deceleration of upper part C. Not seen of course.

What about the upper part C and its 54 060 tons? Is it acting on the rubble layer part B? Not really - upper part C is intact and only its bottom thin floor, floor no. 97, is in contact with rubble part B. The columns of upper part C are now not in contact with the columns of part A below due to this layer of rubble, but let's assume that upper part C columns crushes the columns below as suggested in [2], so that destruction can continue!

In a real collision upper part C should be damaged at the contact area! Bazant & Co just invent part B to hide this fact!

The roof line has then dropped 2.704 m! Air/smoke should be ejected from floor no. 97.

The second Crush - Part B doubles in Thickness - Energy calculations

Then the upper part C + part B (the layer of rubble ) crushes the second uppermost floor of part A. This event can hardly be associated with a second impact by part C as it had just compressed floors 96/95. Regardless, now storey floors 95/94 is compressed into another 0.9 m thick layer of rubble that is added to part B. Part B rubble is thus 1.8 m high/thick after two floors of part A have been crushed.

If a typical storey of part A is 3.6 m tall, it then becomes a 0.9 m thick layer or rubble at crush down. This layer has a mass of 3.67 × 106 kg (or 3 670 tons) and uniform density 1 025 kg/m3.

It is suggested that the first crush down can be initiated by a 0.5 m drop of upper part C, thus the initial potential energy, PE0, applied is 0.5 x 54.06 × 106 x 9.82 = 265.44 × 106 J.

Then upper part C drops another 3.6 m and compresses one storey into 0.9 m of rubble, thus more potential energy, PE1, is applied; 3.6 x 54.06 × 106 x 9.82 = 1 911.13 × 106 J.

Total energy E applied is PE0 + PE1 = 2 176.57 x 106 J or simply 2.18 GJ to crush down the top storey of part A.

Bazant & Co suggest [2] that “the total energy dissipation per unit height, which represents the resisting force Fc, consists not only of energy Fb dissipated by the inelastic hinges formed during column buckling, but also of energy Fs required for comminuting concrete floor slabs, energy Fa required for expelling air from the tower, and energy Fe required for ejecting particles and fragments”.

However, it seems Bazant & Co in their 1-D model miss the friction force required to compress and accelerate the rubble.

Anyway – if total energy E = 2.18 GJ is used to buckle the columns, to comminute one floor, to expel air, eject particles and fragments and to compress the rubble into a 0.9 m layer, then – after this second crush and compression – part C and the rubble would have stopped. 2.18 GJ corresponds to about 606 kWh.

The total volume of rubble is after crushing one storey is 3 700 m3 with a mass of 3 760 tons. The unit amount of energy to compress one ton of rubble is thus only 0.161 kWh/ton. This may be compared with the amount of energy to shred a scrap steel stripped car that is about 36.8 kWh/ton in a very modern recycling factory, or 240 times more. Crushing grapes into wine also requires a lot of energy, the author is being told.

It is realized that shredding a thin steel plate car cannot be compared with compressing a composite steel columns/concrete floor tower, but in the author's the amount of energy to compress one storey into 3 670 tons of rubble seems very low.

The roof line has then dropped 5.4 m! The velocity of the roof line apparently is increasing - but why? It should slow down by so much sudden compression. More air/smoke should be ejected sideways from between floors 96/95, i.e. only from the storey being crushed. Can you see it on any video?

Furthermore, [2] suggests that part C and the rubble do not stop after the first crushes. On the contrary part C continues to accelerate and the rubble is also accelerated, while part A is being crushed again.

Thus we have to deduct the energy required to keep part C accelerating and to accelerate the static rubble to same speed as part C in above calculations to find the energy dissipated only to produce - part B - the rubble of crushing the first or second storey of part A. To accelerate 3760 tons of rubble to 20 m/s requires about 209 kWh, to 30 m/s it is 470 kWh, etc.

If, say, upper part C is not stopped after crushing one storey but continues to accelerate at say 0.65 g and that part B - the rubble - should be brought up from speed 0 to the speed of upper part C, then maybe only 30% of total energy E is available to buckle columns, comminute concrete, expel air, eject particles and fragments and compress the rubble, thus unit amount of energy to compress one ton of rubble becomes only 0.05 kWh/ton or 736 times less than shredding a car. In the author's opinion that is much too little to produce a crush down of any kind of 3-D structure. To crush one ton of grapes into wine requires more than 0.05 kWh. Try! It is a healthy exercise!

A more detailed energy balance is shown here when upper part C has dropped 31.38 meters. The potential energy applied to (lost in) the process is upper part C moving down 31.38 meters and 41.84 meters of part A crushed down 15.69 meters (53 000 000 x 31.38 + 41 840 000 x 15.69) x 9.82 = 22.8 GJ, which means that only 22.8 - 20.4 = 2.4 GJ of energy is used to compress 41 840 000 kg of part A into rubble B or 2 400 000 000/41 840 000 = 57.4 J/kg or 57 kJ/ton or only 0.016 kWh/ton WTC 1 structure.

And so on!

The Displacement of the Roof Line of Part C during Destruction of 13 storeys

According careful observations in [6] we know that the roof line of upper part C dropped 35 m in 3.17 seconds at increasing velocity. We also know that upper part C roof line is accelerating at about 0.64-0.7g [6]! This means that upper part C, or what remains of it, as it is shortened and disappears, can only apply a force of 0.3 g or 30% of its own weight to crush floors of part A and build up the rubble layer - part B - ignoring the fact that it is upper part C that actually implodes.

Every time a storey is crushed, upper part C drops 2.70 m and an 0.9 m layer of rubble is formed according [2] and upper part C is remaining intact according Bazant & Co.

Thus, when the roof line has dropped 35 m, 12.94 storeys (!!), total height 46.6 m (!) of part A should have been crushed, and should have been replaced by an 11.66 m thick layer of rubble – part B - with the upper part C still on top.

Writers of [6] believe that only 9 (or 9.72) storeys have been crushed but according [2] it should be 12.94 storeys! Writers of [6] forget that there should be an 11.66 m thick layer of rubble below the upper part C, when it has dropped 35 m after 3.17 seconds.

Verification of Parts A and B using Video Recordings of the Destruction of 13 storeys

Fig. 11 - Upper Part C being destroyed - No rubble Part B being formed (same as fig. 7 above)

Regardless – does anybody see (fig. 11) an 11.56 m thick layer of compressed rubble – part B – on any video after a 35 m drop of the upper part of WTC 1, part C according [2]? And that 46.6 m of part A - floors 96-85 - has been destroyed after 3.17 seconds?

It would appear that at least floors 85-93 are still intact!

And does anybody believe that an upper part C with density 255 kgs/m3 can produce an 11.56 m thick layer of rubble during 3.17 seconds and at the same time accelerate at 0.64-0.7g? Only [2] suggests so, but it is just an invention to suit a false 1-D mechanics model/theory of a one-way crush down.

This layer of rubble - part B - should then be moving at a velocity of >20 m/s and increasing as acceleration seems to be rather constant 0.64-0.7g. Only air should be ejected from the next storey below being crushed, where more rubble is formed. But upper part C cannot possibly both compress and accelerate part B at the same time! Ah, what funny model [2] invents! Don't they see that upper part C is destroyed?

Fig. 12 - Debris being ejected >100 meters in all directions
Fig. 12 above shows the upper part (??) of WTC 1 about 10 seconds after the roof line started to move. Is it there? Is the upper part hidden by the fountain of debris ... if it is there? According [2] there should not be any debris 100 meters outside the tower at all - just a layer of compacted rubble - part B - on top of part A. Crush down! With part C - the upper part riding on part B. There should not be any debris 100 meters outside the bottom part A!

Video evidence - and this picture - on the other hand show that all parts A (top) , B (doesn't exist or is the rubble 100 meters outside the tower!) and C are exploding or have been destroyed and structural pieces of them are thrown out in all directions 100 meters. You need 1 000 times more energy for that than gravity displacing the upper part downwards for that!

You really wonder if the authors of [2] have studied any videos or pictures of the WTC 1 destruction?
Situations when Part C Roof Line has dropped 100 m, 200 m and when Part B hits Ground

Now – when upper part C has dropped 100 m and 37 storeys have been crushed, the layer of rubble – part B – should be 33 m thick on top of which a 53 m high upper part C should still be visible (forgetting the mast).

An when upper part C has dropped 200 m and 74 storeys have been crushed, the layer of rubble should be an impressive 66 m thick with part C still riding on top of it.

Imagine a layer of rubble - density 1.025 ton/m3 - 66 m high. Over 4 000 m² floor area it is almost a big cube of 264 000 tons of rubble !! On top of which upper part C - 54 060 tons float. Part C is 53 m high! Add the rubble - part B - and we have a moving mass of 318 060 tons that is 119 m high when the upper part C roof line has dropped 200 meters.

Below this 119 m high pile, a storey of part A - floor 23 - is just being crushed and air - not smoke - is ejected there. How the columns of upper part C - 66 m above floor 23 can crush the columns 66 m below is not clear. 266 m of walls should also be gone. There are another 23 storeys still to crush! About 83 m of WTC1 remains to be crushed.


Fig. 4 - Schematics of a crush down of WTC1 on 9/11 by rubble!
Can it be seen on any video? 83 m of part A + 66 m of part B (rubble) and 53 m of part C equal 202 m! If the original tower was 402 m then the roof line should have dropped 200 m when 74 floors had been crushed. Add the mast 40 m. Seen on any video? Note also that upper part C is still accelerating at 0.7g at this time. The speed is of the order 45 m/s! It doesn't make sense. Reason is that parts B and C have disappeared at this time. Part B never existed. And part A is being destroyed by something else!

When all 98 floors of WTC 1 - part A - have been crushed, there should be an 83 m thick layer of rubble on the ground + upper part C on top - 53 m. This is also confirmed by [2] - see fig. 13 (b) right: just before the end of crush down the 53 m high part C rests on a 92 m thick layer of debris (density 1.025 ton/m3) - the crush down has also penetrated the basement 22 m below ground! The roof line should be 135 m above ground then!
And the velocity of part B at the ground or bottom of basement must be 0! As the velocity of the part B in contact with part C above must be the same as part C, you realize that part B cannot be regarded as one 'part'!

An instant later upper part C is destroyed in a crush-up according [2] and should form a 13 m thick layer of rubble. The total thickness of rubble should be 92 + 13 = 105 m minus 22 m of rubble in the basement = 83 m of rubble above ground but only 20 m is suggested by [2]. Evidently some rubble is spread outside the 4 000 m² foot print, but it seems the density of the rubble must have increased 3 times - 3.075 ton/m3! But it is not possible - it is too dense. So where did all the rubble go?

Fig. 13 - figures from [2]
Actually no rubble - part B - could be produced at all by dropping upper part C, as it should have got stuck up top. All energy applied when upper part C dropped one storey would have been consumed by local failures and friction trying to crush only one storey!

Correspondence with G

After having published above G, Frank Greening, who co-authored [2] asked:

So, Heiwa (that's me), tell me what you see after a 35 m drop!

Again, Heiwa, tell us what you see when there are 36 storeys still to crush.

And I replied:

"Thanks for asking. There is plenty to see on the videos of the WTC1 destruction apart from a 'jolt' that nobody sees. Lately I have concentrated on those features that you postulate in your paper What Did and Did not Cause Collapse of WTC Twin Towers in New York [2] that I found in the Journal of Engineering Mechanics, ASCE, Vol. 134 (2008). And there are plenty features I do not see.

Of course, the title of your paper is misleading. WTC 1 never collapsed! It was crushed down from the top according to you. It - part A/lower structure below floor 97 - was crushed by a layer of rubble - part B - that was created when part C - the upper part floor 98 and above - dropped down. Part A never collapsed - each and anyone of its 97 storeys were crushed, one after the other.

According your paper - as I understand it - part C suddenly dropped (its support were weakened by fire/heat and buckled) and impacted on floor 97 of part A. This impact allegedly destroyed the columns between floor 97/96 and floor 97 dropped down on floor 96. I do not see that on any video.

It is now the crush down of part A starts. When floor 97 drops down it becomes a 0.896 m thick layer of rubble - that you call part B - that contacts floor 96 of part A. This rubble is volume vise about 3 600 m3! The uniform (sic) density of structure floors 97/96 was originally 0.255 according you (plenty of air). The density of the rubble is 1.025 according you so compression takes place. It is part C that compresses structure floors 97/96 75.1%.

I do not see that on any video.

To compress rubble requires energy applied by part C and it seems you do not consider that in your differential equations. To compress rubble you must overcome friction in the rubble. As the solid parts of the rubble have density 7.8 (columns) and 2.5-3.0 (concrete) there must still be plenty of air in part B - the rubble layer.

I do not see this rubble layer on any video. To compress 14 400 m3 of structure with density 0.255 to 3 600 m3 of rubble with density 1.025 requires plenty of energy! I would expect the destruction to stop then. But I do not see that! Instead upper part C soon after accelerates constantly a 0.7g due gravity. Not possible if part C shall compress rubble at the same time.

Anyway, next crush is floors 96/95. Now it is a layer of rubble - part B - with part C on top that damages part A. An impact between parts C and A is impossible with so much rubble in between. You suggest that parts B and C now overloads floor 96 (pancake theory?) so floor 96 drops down.

Fair enough! I don't agree and I do not see it, but this is what you suggest. According videos (and your own paper) acceleration of part C is now 0.65-0.7g.

Part B - the rubble layer doubles in thickness - and the crushing continues another 11 floors of part A at constant acceleration 0.7g.

So after a 35 m drop of part C - it takes 3.17-3.3 seconds according your differential equations and acceleration given above - total 13 floors of part A have been crushed (should be floors 97-84), 46.6 m of perimeter walls have failed in pieces and part B has become 11.56 m thick and part C should remain intact on top of the rubble !

Frankly speaking nobody can see that on any video.

What I see is that part C - the upper part - explodes in its lower part - floors 98-105. Controlled demolition no doubt! That's why the roof line has dropped 35 m. I do not see an 11.56 m thick layer of rubble on top of floor 84! Actually I can clearly see that floors 84-96 are undamaged!

So much for your model and theory, G.

So what do I see, when there is 36 floors to crush (61 floors of part A have been crushed)?

Look right (fig. 14) and imagine that it represents when there are 36 floors to crush! Part A is about 130 m tall at this stage. 61 floors have been crushed so part B should be abt 55 m thick and on top of that we should see upper part C, which is 53 m tall to roof line, and then the 40+ m mast.

Thus, when floor 36 is being crushed - and air/smoke is ejected there and only there - at 130 m above ground we should see, according your theory, a 53 m thick layer of rubble - part B - top of which is 183 m above ground. On top of that we should see upper part C undamaged according your theory, roof line of which is 236 m above ground, and then we should see the mast. There should be no free rubble anywhere ... and no dust!

Fig. 14
But sorry, I do not see all that. What I see is a fountain of debris and rubble thrown 100+ meters sideways in all directions - apparently caused by multiple controlled demolitions executed from top down and plenty of smoke and dust, probably caused by the controlled demolition charges. Sometimes I have a feeling the whole photo/video is a simulation using fake foreground,background, building, destructions, smoke, dust, pieces ejected, etc. The whole thing does not look real.

So, sorry! I cannot see anything that confirms your model and theory, Dr. G. But I wonder! Why do you invent such a stupid model and theory and publish it in the Journal of Engineering Mechanics? Are you working for the perpetrators of the controlled demolitions of WTC 1, 2, 7 or some agents of those? Do you think you can convince anyone with your unscientific nonsense? Why do you do it? Why not simply shut up like most other poor bastards and don't say anything. I don't expect you to be like me that can do real structural damage analysis and quickly see that WTC 1 destruction is not caused by crush down or PE>SE that NIST suggests.

Anyway - I have just updated http://heiwaco.tripod.com/nist7.htm . It seems NIST have destroyed all records how they analyzed and simulated the WTC 7 structural failures as presented in its November 20, 2008, report. There is no calculations, etc, of any kind left by NIST to support the WTC 7 final report! All destroyed ... if it ever existed. The NIST WTC7 report was laughable! A big section above floor 16 was dropping at free fall ... and deformed itself." (end of reply to G).

It is always nice with reader contacts! I will update this page when G clarifies his motives.

But ...

More funny Explanations

The authors of [2] suggest (fig. 15):

Fig. 15 - figures from [2]


The 53 meters high upper part C, intact, rigid and of uniform density at start of crush down remains INTACT after the global crush down ... on top of all rubble that the upper part has produced of the structure below ... and only then finally destroys itself in crush up as illustrated in figure ... left. The destruction of the upper part is the last event of the gravity driven global crush down.

Not seen of course and there is no evidence for it.

You wonder then why the upper part C does not continue through the rubble and the soft ground and makes a big hole in the ground!

Bazant/Greening/Benson make four basic assumptions of the gravity driven crush down ending in Stage 6 apart from the misleading introduction in [2]: "Abstract: Previous analysis of progressive collapse (sic - crush down!) showed that gravity alone suffices to explain the overall collapse of the World Trade Center towers". That conclusion is as valid as a three dollars bill! 3-D structures are not crushed down from above and rubble is not caused by gravity alone.

Further claims by Bazant & Co [2] thus:

(1) The only displacements are vertical and only the mean of vertical displacement over the whole 4 000 m² floor needs to be considered. There is perfect alignment and the upper part columns always hit the lower columns without slipping sideways and the lower structure does not deform

Fig. 16 - Air jets well below the upper part !

How can a column hit a column through a 33 m thick layer of rubble?

(2) Energy is dissipated only at the crushing front! The separate parts of the upper part and structure below of the collapsing tower may be treated as rigid and will not be destroyed(!); the deformations of the structures away from the crushing front may be neglected.
Does it matter if the upper part C is rigid? It is not in contact with the structure below after the first storey crush? And part B - the rubble - cannot possibly be rigid!

(3) The upper part therefore remains intact during the crush down including its lowest floor at the crushing front!

But is the upper part C there at all? And how can soft rubble destroy solid columns?

(4) Air jets (sic) displace broken material 200 metres sideways in all directions.

All these assumptions, apart from being ridiculous, are false. A rigid body, an upper part C, does not exist! By definition a rigid body destroys anything non-rigid it touches. But the upper part C is destroyed before the destruction of the lower structure commences.

Note, e.g. the Bazant explanation for air jets. The upper part C intact, with an air tight bottom floor (with a thick layer of compressed rubble below it - part B) is supposed to compress the air in the top remaining storey below - part A - and blow out (?) the debris and rubble before the wall columns are affected. The crush down has changed in character. No compression - now it is blow out! To compress this storey takes 0.07 seconds according [2], i.e. the velocity of part B - the rubble - is 51.4 m/s! Ask yourself what produces these air jets, if there is no upper part C or rubble layer part B, and when the air jets can be mistaken for smaller air jets seen preceding the destruction - fig. 5 - by 10 storeys. And where does the rubble being ejected come from? It is ejected horizontally! Local failures due to gravity do not produce the big amount of rubble ejected horizontally as seen on the videos! And according [2] the rubble should just be compressed to form part B.

Part V - Over-loading!

Another 'expert', K. A. Seffen, in a paper [3] suggests that the potential energy released by the mass above - the upper part - resulted in dynamical "over-loading" of the undamaged columns of the structure below by a factor of 30 compared to their static load capacity at impact and transmits it to the complete structure below and shakes it into pieces. Seffen also treats the problem in 1-D: a line that becomes shorter!

Seffen assumes that during a gravity driven collapse (or crush down or over-loading) a tower of height L and uniform density ro consists of three parts, when it has lost aL of its height (fig. 17):

1. A solid upper part lL (actually a line) that is rigid and intact and perfectly aligned with the columns below all the time during crush down. It does not slide off!

2. A moving intermediate block bL (another piece of line) between the upper part and a crush front that apparently consist of semi-broken parts, rubble , and produces a crush front, actually 280+ crush fronts that are perfectly applied to the 280+ columns at every stage of the crush down.

Fig. 17 - figure from [3]

3. A static lower, intact part (1-a-b-l), a third piece of line, below the crush front that produces resistance to motion as per fig. 6. It is in fact the 280+ columns of the structure below that produce resistance ... if a load is actually applied on them from above.

l is constant during the crush down, which is not observed during the WTC 1 collapse. Actually l becomes 0 very early!
Photos of the crush down show that the upper part lL disappears and that material, dust and smoke are pushed outwards at high speed of the intermediate bL block.

These are the false assumptions of K.A. Seffen:

(1) the tower has uniform (<0.18) density ro, while it is not uniform at all; it consists of solid columns 0.13% of the floor area (with density 7.8), weak floors 99.87% of the floor area (with density about 3 but spaced 3.7 meters apart) and air (density <0.02) between floors and columns,

(2) the lL upper part begins to accelerate downwards as a rigid undamaged body with uniform density ro, while it is seen to self-destruct,

(3) the initial load imposed onto the structure below was exceptionally high, while is not established how and when it contacts the structure,

(4) the damage, no new failures seen of course in the smoke, was bound to propagate, and

(5) fractures in and friction between locally damaged parts in contact with one another can be ignored.

Alignment of upper part with columns below is conveniently forgotten. According to Seffen the rigid upper part drives the crush down. And the upper part is not slipping off the structure below.

Fig. 18

You need kinetic energy, KE, for that and it can only be provided by an intact, rigid, uniform density upper part that remains intact, rigid, with uniform density during the whole destruction of the structure below. No such object exists anywhere! The upper part is the only part that can provide KE during the alleged global push down. The structure below does not add any extra KE to the destruction or contribute to it - it is being destroyed due to lack of strain energy and lack of friction between parts in contact according NIST. The upper part, intact, rigid and of uniform density at start of crush down, should according to Seffen remain INTACT after the global destruction ... on top of all rubble the upper part has produced of the structure below as per figure 18 left and should then also destroy the rubble. Nothing could destroy a rigid upper part of uniform density - not even the final impact with the ground forgetting that the rubble is there to dampen the final impact.
The lack of the upper part on top of the intermediate block bL rubble after crush down proves Seffen wrong. There should be a big hole in the ground and at the bottom of the hole you should find the upper part - intact!

The Seffen theory is another completely nonsensical theory about the WTC1 collapse.


Part VI - Unproven Assumptions and Collapse Arrest

There are many unproven assumptions by Bazant & Co. associated with the WTC 1 crush down destruction apart from treating the process in 1-D, i.e. lack of evidence for, e.g:

1. All support columns suddenly disappear/buckle in the fire zone below the upper part C (they should just 'kneel').

2. The upper part C near free falls or drops 3.7 meters (it cannot as it is connected via deformed columns to the structure below - part A).

3. The upper part C impacts the structure below, part A, with perfect alignment (it cannot happen!) and produces a layer of rubble, part B.

4. The upper part C and its bottom thin floor are still intact due to massive strain energy in it (it is assumed rigid and remains so for while - compare 7. below).

5. The upper part C (mostly air - uniform density <0.18 or 0.255 [2]) assisted by gravity only destroys the solid steel columns below (the columns break/fracture horizontally every 10-12 meters like spaghetti) and produces 0.9 meter rubble and débris of every storey.

6. Friction between parts, floors, of the upper part C rubbing against parts, floors, of the lower structure does not exist.

7. The upper part C and the rubble part B produce air jets in the structure, part A, below, that blow out the débris and throw out the rubble 200 meters!

8. The upper part C lands intact on a 70-80 m high heap of soft rubble after a successful one-way crush-down of the tower.

9. The upper part C finally self-destructs in a crush-up (sic) of the soft rubble, i.e. suddenly it is not rigid anymore!

As with all real conspiracy theories there are no evidences for them.

Bazant's & Co's crush down theory is based on a rigid, intact upper part C that is not damaged by local failures, when first losing its supports and later, when in contact with the structure below. The upper part C bottom floor (no. 97) remains air tight, flat and solid, etc, like the rest of the upper part C! It thus has massive strain energy built in and is supposed to be much stronger than the structure below (but not stronger than rubble on the ground). But it does not really matter - [2] suggests that a layer of rubble - part B - increasing to 70-80 m thickness destroys WTC 1.

There is no evidence for all this! They are simple lies transmitted only two days after the destruction to fool the public and to hide the real reasons for destruction.

In a previous message to the author 25th April 2008 Frank Greening explains (#617):

"I admit my model calculation is very crude, but it shows that a gravity-driven collapse of WTC 1 & 2 was physically possible without the help of explosives! My model may not “see” everything that happened; you, on the other hand, see things that never happened …… ".

Exactly the Bazant 1-D solid mechanics model is very crude and has nothing to do with reality! The nine invented events or assumptions listed above cannot be seen and never happened. Local deformations, failures, fractures and friction alone of the elements of the 3-D structure would have stopped the destruction very early. Part C would have got stuck up on top of part A. No rubble layer part B would have been formed. And why say that the structure below collapsed, when it was just crushed down one-way by the upper part C producing a rubble layer, part B, and throwing out loose parts sideways according a new phenomenon never seen before? Nobody has ever heard of steel 3-D structures being crushed down by an upper part above with equivalent strength as the structure below, but everything must happen a first time. Twice - within an hour.

Seriously speaking - the Bazant 1-D solid mechanics theory treating the WTC 1 as a line that becomes shorter is complete and utter nonsense!

Collapse Arrest - Happens all the Time!

Bazant, Greening, Benson and Seffen incorrectly assume that the upper part C can absorb massive amounts of strain energy to remain intact during any local failures, i.e. the upper part C is indestructible. That is a puerile assumption and apparently intended to fool people.

What a reasonable person using clear thinking would expect after local failures of supporting structure in the initiation zone - even very serious ones - is that the forces in the structure of the upper part C would be redistributed and cause failures there and that gravity would just slowly (no free fall, no sudden release of PE) pull the upper part C assembly down, i.w.o. local failures. The upper part C is always connected to the structure below albeit by deformed columns. Some parts may then contact the structure below and cause further damages or get damaged like in a soft collision (no impact!), and after that primary and secondary structural parts of the upper part and the structure below would get entangled into one another and friction develops.

No Rubble would be produced!

Evidently the structure below will cause serious damages to the upper part C structure above at once, when the upper part C displaces downwards and makes contact with the static structure below. It means that the Bazant, Seffen, NIST assumption of an undamaged upper part C during the whole destruction or crush down is proven wrong ... at once. This strange misty assumption - that the upper part C remains intact - is suspicious. Very suspicious. Has nothing to do with reality.

The fact that local failures occur but are arrested by deformation and failure of intact 3-D structure and friction between loose parts is the basic reason why a multiple-parts steel 3-D structure does not ever globally crush down like a house of cards!

There are many structural parts that may fail, deform, fracture, be punched and displace in 3-D - connected to one another one way or another forming the 3-D structure of the upper part C. You cannot simplify and say the upper part C is only one solid, rigid mass of uniform density on a line - 1-D - that remains intact. There are four outer walls and core columns - all primary structure, many floors - all secondary structure -, a roof, and plenty of air!

If the upper part C masses drop or move, their PEs become KEs. Each part mass has its own PE/KE due to gravity. And each part mass starts at a different location and will drop on a different location by gravity on the structure below.

The structure below of WTC1 is fairly complex - 280+ columns, 94 floors, etc. The columns only occupy 0.13% of the total cross area of the tower. What loads are applied on them at an impact? Probably none as they are small and any load will slip off.

The uppermost floor of the structure below thus occupy 99.87% of the cross area. What loads are put on it and where and when? There are different masses dropping down or moving. And what parts will rub against each other and what are the frictional forces?

In order to analyze the damage initiation you evidently apply the loads to the structure below and see what happens! Does global collapse or crush down or whatever starts and is rubble produced or is it just local failures that are arrested and no rubble? [4] The analysis is based on experience from ship collisions.

No Rubble is produced by local Failures!

So let's assume (see fig. 19 below) that the upper part gets lose (A). It means that the potential energy available in a one-story drop was greater than the local strain energy to be overcome in the initiation zone, i.e. crushing all columns there. It is furthermore assumed that the compressive force, necessary for a descent was available; otherwise the motion would not start, i.e. no initiation. If these assumptions are not fulfilled, the conclusion is that the motion will be arrested already during the damage of the initiation zone and the building will stand.

What happens then?

In this funny simulation complete upper part (floors are not bolted to the columns) first bounces on the lower structure as expected, upper part perimeter wall then becomes disconnected from core (no bolts assumed) and will drop down outside while upper part core gets entangled in the lower structure core and is arrested there. Lower structure perimeter wall remains in place! Nothing is resting on it!

However, let's assume that the upper part gets misaligned (exaggerated in fig. 19 below) and is shifted outside the lower structure on two wall sides and inside on the two other wall sides of the lower structure (B) and goes down ©. Similar misalignment takes place at the core. The original interface between upper part and lower structure changes. Before the primary load bearing solid steel columns were connected. Now they are only in contact with secondary structure; the thin, mainly concrete floors or with nothing outside the building! It is now the 'impact' or collision or contact starts.

If the upper part columns are not misaligned with the lower structure columns and there is perfect contact of all columns of upper part and lower structure at collision/impact, the upper part would be subject to a visible jolt and deceleration [6] at contact. As such perfect contact is impossible to take place under any circumstances - the columns will slide off - here it is thus assumed that the solid columns contact the thin floors or air outside the structure.

The upper part walls steel columns (right in C above), misaligned on the inside of the lower structure, will now punch or slice through the first red floor below the initiation zone - the red floor hinges down on the red floor below as it is only bolted to the core column/beam - while the upper part walls steel columns (left in picture C above) misaligned on the outside will drop in the air and hit nothing! Actually only half the mass/walls of the upper part carried by the walls participate in the local failures/crashes that follow and results in tilting of the upper part.

;;;;;;;;A ;;;;;;;;;;;;;;;;;;;;;;;;;;B ::::::::::::::::::::::;;;;;;C:::::::::::::::::::::::::::: xxxxxxxxxxxxxxxxxxE

Fig. 19 - What happens when two similar structures impact each other

On the other hand the steel columns of the structure below (left in C above) on the inside of the upper part will slice/punch through the first, lowest green floor of the upper part - and it hinges down too on the red floor below! You do not need much energy for that. And the walls steel columns of the structure below on the outside of the upper part (right in picture C above) will remain ... intact, as they are not contacted by anything!

Similar floor failures occur at the core but there the steel columns are fewer and spread around and interconnected by horizontal beams to which the floors are bolted. These latter connections will shear off and the floors will hinge down around the opposite edge.

Does anyone believe that the upper part will fall vertically - at near free fall speed - under these circumstances of local floor failures - and crush down parts below - which is the fundamental assumption of Bazant, Greening and Seffen? No free rubble (lose structural parts) can be produced that would provide extra energy and drive the destruction further!

What a free fall drop is, is explained at web site http://uk.youtube.com/watch?v=gC44L0-2zL8 . Or try to click here! The WTC 1 collapse can be seen at web site http://www.youtube.com/watch?v=dtx_GcFCs...annel_page . Or try to click here here! Internet is funny. Sometimes the link doesn't work! I wonder why?

Progressive local failures of structural parts have however started in the little example due to the original energy input and local failures! Thus we have to see what happens at the next floors above and below applying all the relevant contact loads there in proper order as per [4].

The upper part is thus assumed to continue moving down due to gravity, but there is no free fall, only local failures and fractures in the floors and friction between bent and punctured parts in contact producing friction and absorbing energy and slowing the downward movement. No rubble is produced! No air jets are produced! And no débris can be ejected as there is no loose débris produced!

In D the upper part right wall solid steel columns inside the structure below are assumed to have sliced three red floors in the structure below and these floors have hinged down below the green floors of the upper part that have also been cut by the strong wall columns of the structure below inside the upper part. Similar failures take place at the core.

Massive frictional Forces develop

Evidently this asymmetric destruction pattern of local failures will tip the upper part against the intact (right in D above) steel wall of the structure below held together by spandrels and the upper part will soon be jammed, e.g. in E when outside walls of the upper part (left in E above) has been sliced off by the columns below and dropped to the ground. All the floors of the upper part however remain jammed in the top of the structure below.

Fig. 20 - from [6]
If the upper part drops and accelerates at 0.75 g [6] and the punching of holes in the floors by the columns and hinging down of the locally failed floors take no time, the upper and lower floors themselves, spaced 12 feet apart, will contact each other after about 1.0, 1.4, 1.75, 2.08, 2.3, 2.53, 2.75,2.88, 3.17 and 3.3 seconds, i.e. after 3.3 seconds 10 floors of the upper part would be entangled in 10 floors of the lower structure ... and the WTC1 would be 120 feet shorter as per above fig. 20. It is very likely that the destruction would be stopped earlier.

The progressive local failures of secondary structural parts are thus arrested. No rubble has been produced. The main reason for this is that the failed floors are in contact with each other and rub against one another and huge frictional forces develop that absorb the released potential energy much more effective than any built in strain energy of intact structure that deforms. NIST, Bazant and Seffen do not even consider that friction between locally damaged parts exists!

This logical local pattern of destruction is not considered by NIST, Bazant or Seffen.

Other Possibilities

There are other possibilities of serious local structural failures and what may happen. In fig. 21 below it is assumed that three green floors in the upper part fail in their bolted connections to the wall columns (B) due to fire/heat in the initiation zone and that the green floors hinge down on the red top floor of the structure below. The green floors are still connected/bolted to the core acting as a hinge.

Fig. 21 - Wall panels dropping off

The result would be that the walls in the fire zone buckle inwards on top of the green floors that dropped down previously ©. The walls of the upper part are then hanging on the hat truss in the roof that is assumed to deform downwards. The walls above do not transmit any forces to the walls of the structure below!

The outside floors in the upper part are thus pulled down by the unsupported walls of the upper block. The extra load in the hat truss is transmitted to the core columns at the top that buckle locally at the weakest areas just below the hat truss due to overload. The roof and the mast on top displace downwards © a couple of meters. Due to these deformations and displacements of the upper block parts the floor bolts shear off at the walls (it is assumed they remain intact at the core), the walls of the upper block gets loose and falls down (D) and slips off on parts off the walls previously buckled inwards acting as a damper on top of the damaged green floors in the initiation area and drops to the ground ... and the collapse is arrested. Or the green floors hanging on the upper part core pull down the upper block core more until they contacts the inwards buckled wall below and are diverted outside the tower ... when further destruction or collapse is arrested. No crush down will occur! No free rubble is produced.

It should be noted that in this second example, fig. 21, the local failures at the fire zone - the green floors dropping down and the walls buckle bending inwards - result in further local failures 58 metres higher up due to local forces in the upper part structure being transferred there due to the first failures below. The upper part is evidently not just one 'parts' but consists of many parts, and the weakest ones will fail, when any supports below fail. Thus the upper part will be part destroyed prior anything can happen to the structure below! This is a fundamental part of collapse arrest analysis of steel structures.

You have to keep an eye on where the forces are transferred after local, initial failures and what really happens to the upper part. Bazant, Seffen, Greening, Benson and others fail miserably in their one dimensional analysis in this respect and therefore make insane conclusions. NIST is worse.

Part VII - Conclusions

How can serious authorities and scientists suggest that a global collapse or crush down of WTC 1 is driven only by gravity and an assumed indestructible, rigid upper part C when the latter - as a smoking gun - disappears before the collapse even starts as per fig. 10 and all videos? Local failures caused by gravity do not produce free falling rubble! The rubble is evidence that gravity only is not at work here. Why do they support conspiracy theories to the contrary? And what about the 'air jets'? Seen on the picture in fig. 22 right? They are supposed to blow out the débris sideways below the upper part C bottom that has just pulverized 30 floors in the structure below with another 60 to go! I only see in the lower left part of the picture a big piece of wall dropping. Crush down? The author sees no upper part C!

The author would expect that the top part of the structure below would only be completely jammed with locally damaged walls, floors and parts of the upper part C and that the upper part C and lower structure may be locally sliced apart at various areas. The remaining upper part C masses that have not yet come in contact with the lower structure should then not do much further harm. They will remain on top. No real rubble would have been produced. All parts would still be connected to other parts except the columns. Only local failures would have taken place.

The collapse or crush down is then arrested by friction between the parts and load re-distributions! It has always happened prior 911. This is the beauty of an airy tower steel structure of non uniform density with strong perimeter wall columns held by spandrels and thin horizontal floors. Some local parts my fail (e.g. floors) due to fire and local gravity overload and then any other loose parts just get deflected, entangled and jammed in the mess, as there is plenty of volume and intact structure for that. A stable state of a partially damaged structure will develop. And this normally takes place without much noise, smoke, dust or rubble.
Spot the 58 meters high upper part C and any air jets!

Fig 22. WTC1 7 seconds after collapse initiation. Is the solid, upper part C really there? Does gravity alone throw big pieces of steel structure sideways and upwards? According Bazant/Seffen these parts are supposed to be compressed! Does gravity produce air jets? Does gravity produce rubble? The rubble is clear evidence of another supply of energy than gravity causing the destruction.
Collapse arrest is when a stable state of a partially damaged 3-D structure has developed [4]. It always happens when a small piece of a structure contacts a larger piece of same structure.

No global collapse or crush down will ensue. But we do not see it on any videos.

NIST in its 10 000 pages report does not mention or analyse the destruction of the upper part C or collapse arrest as a logical result of local structural failures in the initiation zone and the report is thus incomplete.

NIST intentionally fakes its report by assuming that the upper part C is rigid during crush down and non rigid during crush up.

Dangerous Sect at Work

In the struggle against great, organized, sectarian forces of intolerance and insane self-assertion it is important that scientific reports, papers and analysis of damaged and destroyed steel structures are done by honest people using correct thinking, right feeling and proper estimating of facts. Confused thinking, bad passions, dishonesty, corrupt manners, erroneous assumptions and haste do not contribute to a better understanding of the world around us. They are only normal parts of dangerous sects that threathen us.

You cannot crush an isotropic or composite 3-D structure A by a part C of itself (C = 1/10 A) by dropping part C on A using gravity. Part C either bounces on A or gets damaged in contact with A and is stopped by A that is also damaged a little.

It is quite basic and all due to forces and that part C has identical structure as part A.

Materials, size and particulars of the elements of the structure A doesn't matter the least. Part C of A cannot destroy A.

References

[1] Why Did the World Trade Center Collapse? - Simple Analysis

Zdenek P. Bazant, F.ASCE, and Yong Zhou (2001)

[2] What Did and Did not Cause Collapse of WTC Twin Towers in New York

Zdenek P. Bazant, Jia-Liang Le, Frank R. Greening and David B. Benson (2008)

[3] Progressive Collapse of the World Trade Centre: a Simple Analysis

K. A. Seffen, Cambridge University

[4] Development of progressive Collapse Analysis Procedure and Condition Assessment for Structures

Professor Ted Krauthammer, Protective Technology Center, The Pennsylvania State University, Robert L. Hall, PhD, Stanley C. Woodson, PhD, James T. Baylot, PhD, John R. Hayes, PhD, US Army Engineer Research and Development Center, Young Sohn, PhD, Defense Threat Reduction Agency

[5] Mechanics of Progressive Collapse: Learning from World Trade Center and Building Demolitions

Zdenek P. Bazant, F.ASCE, and Mathieu Verdure (2007)

[6] The Missing Jolt: A Simple Refutation of the NIST-Bazant Collapse Hypothesis

Graeme MacQueen, Tony Szamboti, January 14, 2009

[nik]

Good work, icosa. that should be ample to keep any credible engineer seriously interested in the subject, quiet for a while

[JazzRoc]

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HOLY-MOLY-MOTHER-MALONEY, WHAT A BAG OF SHIT AND BALONEY!
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HUGE divert!!!!!! LOLOLOLOL!!!!!!
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Abso-bloody-lutely amazing!





Note that snapped column-ends face inward - which rules out ANY internally-placed explosion.

I repeat, what forensic case might be made for this hole?

What shape is it?

The above is a simple question. What stops you from answering it?

>>>>>>> A N S W E R --- T H E --- F U C K I N G --- Q U E S T I O N <<<<<<<

After you HAVE answered it, I'll set fire to your STRAW MAN.

Or maybe I'll pour cold water on it, and just let it spontaneously combust, like the piece of shit it is...

[icosaface]

Does it rule out a missile? Does it rule out photoshop? Why did they destroy all the evidence? Why isn't the lady in the photo burnt to a crisp what with all that 600 degree C steel heating going on?

[JazzRoc]

(08-30-2010 02:44 AM)rsol Wrote:  ill counter jazz wih a shorter reply. Misdirected. even mayor giuliani talked of molten steel under the towers.

You misdirect here. The question REMAINS: "What shape hole is this, and how was it made?"

Quote:"like a foundry" was a description by a firefighter on the scene. you only have to look. The issue of whether the steel softened or melted causing the "collapse" is a non-issue and merely a distraction from the fact that molten metal was under those sites. Im not talking of a few pictures. im talking about foremen warning their men not to hose an area because of the steam it would cause. THE POINT... was that molten metal was discovered down there... official denial or not. Check the surface temps taken by nasa on the day. WAAAAAYYYY too hot to be two mostly burnt out fires. The fact that WTC7 had a hot spot under it is telling too... Throw any excuse you like at it, oxygen generators was my fave. They keep on insisting that aluminium glows when its hot.

It's never been an issue to any engineer.
If you hammer steel it gets hot. You can melt it by hammering, but you should use a hydraulic forge to do it. You could melt a paperclip with a hammer that way IF YOU COULD STOP THE HEAT ESCAPING.

The calculated mass of one tower (just the steelwork) is 253,000 metric tons, and its total potential energy above grade would have been 3.98 x 10^11 Joules.
The heat required to raise a metric ton of steel from ambient to its melt temperature (temperature range 1110 deg C, specific heat of iron 500J/kg appx) and then melt it (latent heat of melting of iron 98 kJ/kg) is 1000 x ((1110 x 500) + 98000) = 1.53 x 10^8 Joules.
Therefore the maximum possible amount of structural steel that could have been melted by the TOTAL CONVERSION of the tower's potential energy is 3.98 x 10^11/1.53 x 10^8 = 2.6 x 10^3 = 2,600 metric tons.
Assuming a 15% conversion of that energy to melting steel, there might have been 390 tons of molten steel in that pit of hell.

"KEROSENE WILL NOT MELT STEEL!!!" is an utterly straw man brought up by people unaccustomed to either science or hard work and incapable of respecting those who are.

Are you an engineer? Quite obviously NOT. If you cannot acknowledge that a plane made that hole, you are quite obviously UNFIT for jury service too...

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(08-30-2010 02:17 PM)icosaface Wrote:  Does it rule out a missile? Does it rule out photoshop? Why did they destroy all the evidence? Why isn't the lady in the photo burnt to a crisp what with all that 600 degree C steel heating going on?

I know of NO missile that carries 37 tons of kerosine - except a 767.
You can't photoshop a square mile of Manhattan - unless you use a 767s and WTC towers. Then you CAN.
Almost NO evidence was destroyed - except the towers and their contents. Maybe they never existed. Maybe everything (previous history, memories, fossils in the rocks, stars in the Universe) came into existence ten minutes ago.
She's standing in the inrushing updraft fifty feet beneath the remains of the fire and a half hour later.
These questions have already been dealt with, so have the good grace to step back though the thread. And READ it.

[icosaface]

Obfuscating is all you do jr, except when you are prevaricating and distracting. You are a waste of time.

The steel (except for a few anonymous pieces) was removed from the site and taken to steel mills across the ocean for melt down. So you see you prevaricating obfuscating distracting fool, the evidence was destroyed and the convestigation was restricted to a few select pieces of steel which were not identified as coming from WT1 or WT2 or WT7.

If the lady is standing in the hole where the conflagration started then it was not very hot for very long and this means that fire did not weaken the structure.

[nik]

(08-31-2010 02:46 AM)icosaface Wrote:  Obfuscating is all you do jr, except when you are prevaricating and distracting. You are a waste of time.

The steel (except for a few anonymous pieces) was removed from the site and taken to steel mills across the ocean for melt down. So you see you prevaricating obfuscating distracting fool, the evidence was destroyed and the convestigation was restricted to a few select pieces of steel which were not identified as coming from WT1 or WT2 or WT7.

If the lady is standing in the hole where the conflagration started then it was not very hot for very long and this means that fire did not weaken the structure.

Come on now,icosa. You can't have it both ways, The kerosine had obviously already done the damage to the steel in the first few moments before after it had all burnt out and the heat given off initially must have been hot enough that the steel must have just managed to carry on melting after the kerosine fuel was gone.

In terms of the steel, I do know that heaps of it had to be urgently transported to China to help build the USS New York in efforts to preserve buoyancy in the global economy in wake of the attacks :

[JazzRoc]

(08-31-2010 02:46 AM)icosaface Wrote:  Obfuscating is all you do jr, except when you are prevaricating and distracting. You are a waste of time.

The terrorists' behavior is excusable: yours isn't. You live in a sophisticated society which practices science and technology and strives for a full understanding of the material world, and fill your stomach as a consequence. But you don't respect it, or the scientists and engineers that made it. You ARE a useless eater, indeed, exactly like the people you condemn.

Quote:The steel (except for a few anonymous pieces) was removed from the site and taken to steel mills across the ocean for melt down. So you see you prevaricating obfuscating distracting fool, the evidence was destroyed and the convestigation was restricted to a few select pieces of steel which were not identified as coming from WT1 or WT2 or WT7.

So this isn't the evidence?
http://sites.google.com/site/wtc7lies/ai...artsnyc911
Would you want 1/2 million tons of steel kept in a museum? NO. And it would pleasure me to kick your bullshit right back up your ass.
You believe that it was thermited, I know, and the "proof" was thus concealed. But you only believe that because you lack both wisdom and imagination and respect for those experienced engineers and scientists that have already provided a reasonable explanation for a destruction event which by its very nature was impossible to fully itemize. Jones and his crowd, whose words you cling to, are a tiny minority of fools (which always occur), but you'd rather ignore the 99% and go for the 1% that share your delusion. There's always 1% that will say ANYTHING for their 15 minutes of fame, but you haven't even THAT excuse.

Quote:If the lady is standing in the hole where the conflagration started then it was not very hot for very long and this means that fire did not weaken the structure.

The HOLE? You mean the AIRCRAFT-SHAPED HOLE formed RANDOMLY by "INTERNAL IMPLOSION" - TWICE?
The picture that is a detail of shows the building brewing up a building-wide fire. The angled airplane strike carved a "chimney" between three floors and blew out ALL the floor partitions, cutting an obvious route for the progression of the fire. You can SEE this. Flowing beneath the insulation-stripped ceilings was an air mass several HUNDRED degrees hotter than the temperature at which the steelwork SOFTENS.
"SOFTENING" means LOSING ITS STRENGTH back down to the strength of aluminum. This ONLY had to happen where the ceiling line met the wall line, everywhere, for it to be IRRECOVERABLE.
But the building was already weakened and out-of-shape. A ten-fold load factor was in the process of disappearing.
Why do I bother? You've ALREADY MADE YOUR MIND UP, and have already ignored the thousands of small clues which demonstrate that EVERYONE left alive anywhere was CLUELESS as to what was going to happen next.
The way you idiots treat the real-time 911 media response makes this QUITE obvious.
You disgust me.

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(08-31-2010 04:04 AM)nik Wrote:  The kerosine had obviously already done the damage to the steel in the first few moments before after it had all burnt out and the heat given off initially must have been hot enough that the steel must have just managed to carry on melting after the kerosine fuel was gone.

Nik, your flame-baiting is a sign you're over the edge. No wonder you've been sacked. You should be ashamed. Try going to bed earlier. Dream about the question you won't answer.

"What shape hole is this, and how was it made?"