911 and the Demo Truth
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From: Michael Moroney on 12 Oct 2009 17:39 Henry <9-11truth(a)experts.org> writes: > Conspiracy theorists tried to claim that WTC7 suffered severe >structural damage on one side. It was pointed out that if one >side had been severely damaged, any collapse would have started >on that side, and the building would have tilted towards the >damage. You denied that fact, and I proved you wrong yet again. >See how it applies now, or are you still confused? > Also, do you still believe that if supports on only one side of >a tall building are destroyed, the building will drop straight >down onto its own footprint? If so, who do you "think" faked all >the photos and videos showing tall buildings topping sideways, >and why do you "think" they did it? <vbg> Something will fall over like a tree or the buildings in that video if, and only if: 1) The upper portion remains strong and rigid enough to act like a single solid body; 2) There is no structural support below the center of mass of the upper portion, and no structural support on one entire side of the center of mass (the side to which the upper portion would fall); 3) The structural support on the other side of the center of mass is strong and rigid enough to act as a fulcrum since the entire load of the upper part is now on a very small portion; and 4) Structural supports further away from the fulcrum will fail under tension as the upper portion starts to tip away. From the video of the collapse of the south tower, it appears the 1) and 2) were true, but the "fulcrum" failed from the sudden load (the entire mass of the upper portion on the side it was tilting toward) after the top rotated only a certain extent. Once it failed, the top went pretty much straight down, For the north tower, there was never a significant time when 2) was true (there was structural support on both sides of the center of mass, until there was no structural support on either side and the top went straight down) For WTC7, we know it mostly collapsed to the south, but not near the extent of "falling over". It probably failed in the order: central supports, south supports, north supports, but the time between the last two events were short enough so there was no "falling over". (the time from the first to the last would be about the time between the east penthouse vanishing to the general collapse) Unfortunately, there is insufficient evidence to show anything other than that the north exterior wall collapsed as a unit.
From: knews4u2chew on 12 Oct 2009 21:05 On Oct 12, 11:22 am, "AllYou!" <ida...(a)conversent.net> wrote: > Innews:hav96v$fue$15(a)ruby.cit.cornell.edu, > Henry <9-11tr...(a)experts.org> mused: > > > > > Gunner Asch wrote: > >> On Tue, 06 Oct 2009 14:28:04 -0400, Henry > >> <9-11tr...(a)experts.org> wrote: > > >>>> LOL! Well, you've finally taken to selective snipping, which > >>>> is the final refuge of the person who knows they have lost > >>>> the debate. The obvious flaw in your comment is that you > >>>> think steel has to heat to 2500 degrees before it weakens. > > >>> No, it has to be heated to over 2500 degrees before it melts, > >>> a > > >> I notice you keep avoiding "weakens" and keep going straight to > >> "melts" > > >> Why is that? > > > Because it did melt, and if it had gradually weakened, the > > buildings wouldn't have suddenly exploded and disintegrated. > > Just some of the stupidity you spout: > > 1) You claim that the buildings exhibited all of the > characteristics of a controlled demolition, and yet controlled > demotions of buildings cause them to implode, not explode. You're > reading from at least two different whacko sites, and getting > confused. > > 2) Look up the word 'disintegrate' and then reconcile that with > ground zero. > > 3) 'Gradually weakening' doesn't mean 'gradually fail'. Take a > steel cable, put it under 99% load capacity, and then 'gradually' > heat it up. Keep heating it. Does it fail just as gradually as > it's heated, or does it fail catastrophically? > > > They would have shown gradual, isolated, and asymmetric bending > > or sagging in the areas of extreme heat. > > 1) There's nothing about gradula heating that causes anything to be > asymetric.] > > 2) How do you know that the trusses didn't sag to some degree > before failing? If you do, prove it. > > 3) The sagging was isolated to the buildings. > > 4) Steel begins to weaken (and hence, sag) with every increase in > temperature, no matter how small. > > > There a reason you > > conspiracy theorists can't cite even *one* example of a steel > > framed high rise that collapsed due to fire.... > > You kooks can't give one reason why all major building codes require > the steel to be fireproofed. > > > Why do you think WTC7's entire hurricane, earthquake, and fire > > resistant steel frame > > Why do you think its frame was fire resistant? > > > suddenly dropped at free fall speed? > > It didn't. > > > We > > know > > You mistakenly believe. > > > that gradual weakening due to the gradual heating of a few > > columns can't cause that. > > Sure it can. Liar. It wasn't a house of cards. 47 core columns. Hundreds of perimeter columns. Where are the pancakes? How was it turned to mostly dust? H
From: AllYou! on 13 Oct 2009 07:42 In news:936658c6-b1b3-444b-946c-dbc9b347170a(a)f20g2000prn.googlegroups.com, knews4u2chew(a)yahoo.com <knews4u2chew(a)yahoo.com> mused: > On Oct 12, 11:22 am, "AllYou!" <ida...(a)conversent.net> wrote: >> Innews:hav96v$fue$15(a)ruby.cit.cornell.edu, >> Henry <9-11tr...(a)experts.org> mused: >> >> >> >>> Gunner Asch wrote: >>>> On Tue, 06 Oct 2009 14:28:04 -0400, Henry >>>> <9-11tr...(a)experts.org> wrote: >> >>>>>> LOL! Well, you've finally taken to selective snipping, which >>>>>> is the final refuge of the person who knows they have lost >>>>>> the debate. The obvious flaw in your comment is that you >>>>>> think steel has to heat to 2500 degrees before it weakens. >> >>>>> No, it has to be heated to over 2500 degrees before it melts, >>>>> a >> >>>> I notice you keep avoiding "weakens" and keep going straight >>>> to "melts" >> >>>> Why is that? >> >>> Because it did melt, and if it had gradually weakened, the >>> buildings wouldn't have suddenly exploded and disintegrated. >> >> Just some of the stupidity you spout: >> >> 1) You claim that the buildings exhibited all of the >> characteristics of a controlled demolition, and yet controlled >> demotions of buildings cause them to implode, not explode. >> You're reading from at least two different whacko sites, and >> getting confused. >> >> 2) Look up the word 'disintegrate' and then reconcile that with >> ground zero. >> >> 3) 'Gradually weakening' doesn't mean 'gradually fail'. Take a >> steel cable, put it under 99% load capacity, and then >> 'gradually' heat it up. Keep heating it. Does it fail just as >> gradually as >> it's heated, or does it fail catastrophically? >> >>> They would have shown gradual, isolated, and asymmetric bending >>> or sagging in the areas of extreme heat. >> >> 1) There's nothing about gradula heating that causes anything >> to be asymetric.] >> >> 2) How do you know that the trusses didn't sag to some degree >> before failing? If you do, prove it. >> >> 3) The sagging was isolated to the buildings. >> >> 4) Steel begins to weaken (and hence, sag) with every increase >> in temperature, no matter how small. >> >>> There a reason you >>> conspiracy theorists can't cite even *one* example of a steel >>> framed high rise that collapsed due to fire.... >> >> You kooks can't give one reason why all major building codes >> require the steel to be fireproofed. >> >>> Why do you think WTC7's entire hurricane, earthquake, and fire >>> resistant steel frame >> >> Why do you think its frame was fire resistant? >> >>> suddenly dropped at free fall speed? >> >> It didn't. >> >>> We >>> know >> >> You mistakenly believe. >> >>> that gradual weakening due to the gradual heating of a few >>> columns can't cause that. >> >> Sure it can. > > Liar. Prove that I lied. > It wasn't a house of cards. It wasn't up there by magic, either. > 47 core columns. Which required latteral support. That's why they were there. > Hundreds of perimeter columns. That required latteral support, and each other. And many were missing. > Where are the pancakes? IHOP > How was it turned to mostly dust? It wasn't. The sheet rock was, but not the concrete. But how does thermite turn the concrete to dust? > H
From: Henry on 13 Oct 2009 10:03 AllYou! wrote: > knews4u2chew(a)yahoo.com <knews4u2chew(a)yahoo.com> mused: >> WTC 7 was gutted from inside and fell into itself in near perfect >> symmetry at near free fall speed. > It did fall rather symmetrically, but not only did it not fall at > free-fall speed, Your conspiracy kook lies certainly are stupid, blatant, and easily exposed. Thanks to the efforts of 9-11 Truth experts, even NIST has finally been forced to admit that WTC7 did in fact drop at free fall speed,. Now you're arguing against government hired "researchers", 9-11 Truth experts, and video evidence. As always, here's hard proof. http://www.globalresearch.ca/index.php?context=va&aid=15201 NIST's Miracle Members of the 9/11 Truth Movement had almost from the first been pointing out that WTC 7 came down at the same rate as a free-falling object, at least virtually so. NIST'S Denial of Free Fall: In NIST's Draft for Public Comment, it denied this, saying that the time for the upper 18 floors to collapse "was approximately 40 percent longer than the computed free fall time and was consistent with physical principles." Implicit in this statement is that any assertion that the building did come down in free fall would not be consistent with physical principles - that is, the principles of physics. Explaining why not, Shyam Sunder said at a technical briefing: A] free fall time would be [the fall time of] an object that has no structural components below it.... [T]he ... time that it took... for those 17 floors to disappear [was roughly 40 percent [longer than free fall]. And that is not at all unusual, because there was structural resistance that was provided in this particular case. And you had a sequence of structural failures that had to take place. Everything was not instantaneous. Chandler's Challenge: However, high-school physics teacher David Chandler challenged Sunder?s denial at this briefing, pointing that Sunder's 40 percent claim contradicts "a publicly visible, easily measurable quantity." The following week, Chandler placed a video on the Internet showing that, by measuring this publicly visible quantity, anyone knowing elementary physics could see that "for about two and a half seconds..., the acceleration of the building is indistinguishable from freefall." Finally, Chandler wrote a comment to NIST, saying: "Acknowledgment of and accounting for an extended period of free fall in the collapse of WTC 7 must be a priority if the NIST is to be taken seriously." NIST Admits Free Fall: Amazingly, NIST did acknowledge free fall in its final report. It tried to disguise it, but the admission is there on page 607. Dividing the building's descent into three stages, it describes the second phase as "a freefall descent over approximately eight stories at gravitational acceleration for approximately 2.25 s[econds]." "Gravitational acceleration" is a synonym for free fall acceleration. So, after presenting 606 pages of descriptions, testimonies, photographs, graphs, analyses, explanations, and mathematical formulae, NIST on page 607 says, in effect: "Then a miracle happens." Why this would be a miracle was explained by Chandler, who said: "Free fall can only be achieved if there is zero resistance to the motion." The implication of Chandler's remark is that, by the principles of physics, the upper portion of Building 7 could have come down in free fall only if something had removed all the steel and concrete in the lower part of the building, which would have otherwise provided resistance, and only explosives of some sort could have removed them. If they had not been removed and the upper floors had come down in free fall anyway, even for only a second or two, a miracle would have happened. That was what Sunder himself had explained the previous August, saying that a free-falling object would be one "that has no structural components below it" to offer resistance. Having stated in August that free fall could not have happened, NIST also stated that it did not happen, saying: "WTC 7 did not enter free fall." But then in November, while still defending the same theory, which rules out explosives and thereby rules out free fall, NIST admitted that, as an empirical fact, free fall happened. For a period of 2 and a fourth seconds, NIST admitted, the descent of WTC 7 was characterized by "gravitational acceleration (free fall)." Knowing that it had thereby affirmed a miracle, meaning a violation of a law of physics, NIST no longer claimed that its analysis was consistent with the physical principles. In its Draft put out in August, NIST had repeatedly said that its analysis of the collapse was ?consistent with physical principles.? One encountered this phrase time and time again. In its final report, however, this phrase is no more to be found. NIST thereby admitted, for those with eyes to see, that its report on WTC 7, by admitting free fall while continuing to deny that explosives were used, is not consistent with the principles of physics. [56]" -- http://911research.wtc7.net http://www.journalof911studies.com/ http://www.ae911truth.org
From: Henry on 13 Oct 2009 10:05
Iarnrod wrote: > There is no force on planet Earth that could divert that 30-story > upper block sideways that far. Observe the rotating and disintegrating block on the South Tower. http://911research.wtc7.net/wtc/evidence/photos/wtc2exp4.html Notice that the corners are curved, as the block's internal destruction is already taking place. If it had not been destroyed through demolition, it would have continued to rotate and fall off the building as an intact block. Also, notice that the block is tilting towards the corner where it was impacted. The opposite corner was undamaged by impact or fire, as proved by photo evidence. http://911research.wtc7.net/wtc/evidence/photos/wtc2exp1.html As the top section of that tower is rotating, the high strength, fire resistant perimeter columns on one side of the building are being compressed, and on the opposite side, where the building was not damaged by fire or impact, the weight above them is greatly reduced. Why do you think the undamaged steel perimeter frame with reduced weight above it is exploding and collapsing at the same rate as the fire and impact damaged side that has most of the weight of the rotating block on it? Seems more than a little odd, doesn't it? Here's some information on the perimeter columns. -- http://911research.wtc7.net http://www.journalof911studies.com/ http://www.ae911truth.org |