Latest News › Forums › Discussion Forum › Engineering Prof releases draft report on 9/11 collapse of WTC Bldg 7 in NYC
- This topic has 245 replies, 1 voice, and was last updated 4 years, 9 months ago by Clark.
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September 11, 2019 at 10:11 #47080Clark
– ” the UAF report demonstrates why it <i>couldn’t</i> have been progressive collapse”
The UAF report couldn’t possibly do that, because all they have to work from are WTC7’s design documents. The wreckage was disposed of years ago; components could have been beneath specification, wrongly fitted, or even omitted entirely during construction, but we have no way to know. I’m not discounting the report as useless, but it seems extremely unlikely that it can conclusively prove much beyond NIST’s report being wrong, and Chandler already did that.
If you’re really that interested in WTC7 for its own sake, there are two other major engineering investigations that were done for a court case and its appeal. You’ll probably need to read them anyway, because the earlier UAF work made extensive reference to them.
September 11, 2019 at 10:55 #47086DaveRemoving the debris/evidence from a crime scene is itself a criminal act and the fact it happened and without prosecution is evidence of official complicity in both crimes.
September 11, 2019 at 11:01 #47087DaveNo the onus is on you to answer first, because you are saying views on one subject invalidate views on another subject, so need to explain the other subject, otherwise you shouldn’t mention it.
September 11, 2019 at 11:37 #47088Clark– “you are saying views on one subject invalidate views on another subject”
No, you rolled up here and launched immediately into character assassination with your insinuation that someone had sold their soul, and then directly accused me of audacity and gall. You’re just getting back what you repeatedly put out.
The Twin Towers didn’t turn to dust, and their floor systems were not stronger lower down than further up, so there is no need for me to invalidate your on-topic contributions; I just want it to be clear what sort of person is hurling insults at me.
September 11, 2019 at 11:42 #47089DaveNo debris was needed to compile the UAF, otherwise they wouldn’t have compiled it, they just needed details of the structure concerned.
To say you need the debris to prove the building didn’t fall at free fall speed into its own footprint due to shoddy construction is just the usual gall from Clark, worthy of another medal to add to his, you can’t say it was free fall because it was a second out!
September 11, 2019 at 11:54 #47090ClarkCircumstantial evidence that something was hidden tells us nothing about what was hidden.
The Port Authority disposed of the wreckage. The Port Authority also authorised the, er, rather unconventional WTC designs to be built, and after the collapses tried to withhold the plans from the engineering investigations. The New York building industry is also rife with corruption. Demolition mythology actually supplied a convenient decoy for them.
September 11, 2019 at 11:58 #47091ClarkYou again demonstrate your own lack of understanding. g is a rate of acceleration whereas free-fall is a physical condition. To give a trivially obvious example, a bicycle may accelerate horizontally at g, but no one would therefore insist that it was in free-fall.
And the units of g aren’t seconds.
September 11, 2019 at 12:05 #47092Clark– “UAF […] just needed details of the structure concerned”
And they can’t get that without the debris, because the plans may not have been adhered to. Such malpractice is actually fairly common in the building industry.
September 11, 2019 at 18:26 #47095DaveMore gall!
September 11, 2019 at 18:32 #47096DaveBut not to the scale you propose and with such remarkable timing. Find Jesus!
September 11, 2019 at 20:43 #47097ClarkThere’s nothing odd about the timing (sigh); WTC7 had been hit by the collapse of WTC1. It had a gash that spanned multiple floors, it was bulging, leaning and burning. Fire-fighters were measuring its deformation, “up on the transit”. If there was ever a time for a weakness to show up, that was it.
I didn’t propose any scale. I said I thought a team working with the fire-fighters might have hastily demolished WTC7 on the semi-quiet, so that rescue operations could be resumed in the exclusion zone around it.
September 11, 2019 at 23:47 #47102Node“The 9/11 Commission and its final report are still held up as the final word on the events of September 11, 2001. But there’s just one problem: Six out of the 10 commissioners have admitted that the commission was misled, stymied, hampered by conflicts of interest, and, ultimately, forced to participate in a politically-motivated cover-up. This is the story of the doubtful 9/11 commissioners.”
September 12, 2019 at 09:18 #47106DaveYes as Christopher Bollyn says the authors of the crime reveal themselves as they block investigations into the crime.
September 12, 2019 at 17:05 #47116ClarkHave any readers here actually read the 9/11 Commission Report, or any part of it? I haven’t.
It is not widely realised that much of the 9/11 Commission Report was derived from interrogation under torture:
– …441 of the more than 1,700 footnotes in the Commission’s Final Report refer to the CIA interrogations. Moreover, most of the information in Chapters 5, 6 and 7 of the Report came from the interrogations. Those chapters cover the initial planning for the attack, the assembling of terrorist cells, and the arrival of the hijackers in the U.S. In total, the Commission relied on more than 100 interrogation reports produced by the CIA. The second round of interrogations sought by the Commission involved more than 30 separate interrogation sessions.
[…]
– Four of them [detainees] said they gave information only to stop the torture. Although details were redacted in all the detainees’ testimony, the tribunal permitted the inclusion of a letter from a detainee’s father in one case, citing what he claimed was American torture of his son. In the letter placed in the record, Ali Khan claims his son, Majid, underwent extensive torture before and after interrogation sessions.– “The Americans tortured him for eight hours at a time, tying him tightly in stressful positions in a small chair until his hands feet and mind went numb. They retied him in a chair every hour, tightening the bonds on his hands and feet each time so that it was more painful. He was often hooded and had difficulty breathing. They also beat him repeatedly, slapping him in the face, and deprived him of sleep.
– “When he was not being interrogated, the Americans put Majid in a small cell that was totally dark and too small for him to lie down in or sit in with legs stretched out. He had to crouch. The room was also infested with mosquitoes. This torture only stopped when Majid agreed to sign a statement that he wasn’t even allowed to read. But then it continued when Majid was unable to identify certain streets and neighborhoods in Karachi that he did not know.”
I shan’t bother with a link as I know you lot are only interested in collapsing buildings.
September 12, 2019 at 18:25 #47120DaveThe guilty torturing the innocent to absolve themselves of blame!
September 13, 2019 at 01:07 #47128michael55Clark said ”And they can’t get that without the debris, because the plans may not have been adhered to. Such malpractice is actually fairly common in the building industry.”
If such malpractice was fairly common, then it begs the question why other buildings of this type have not come down in a similar fashion. Maybe it’s just a New York thing?
September 13, 2019 at 07:12 #47131ClarkIt’s common because they can usually get away with it. Once the building is complete you can’t tell whether components were missing when the concrete was poured, and not many buildings get hit by aircraft or whatever.
But yes, it does happen, eg. the Ronan Point collapse in 1968:
– Further construction defects had led to the whole weight supported by each wall panel being supported by the panel beneath by two steel rods, instead of being spread evenly along the panel, leading to extremely high stresses that the concrete was not designed to withstand.
– The strengthening brackets which had been fitted during the rebuilding were in many cases not properly attached, since they were fastened to hollow-core slabs, and in many cases they had been bolted only to the thin concrete surrounding the cores, which was inadequate to take the stress.
– The concern […] eventually led the council to evacuate the building, and then to demolish it in 1986 in a forensic manner (rather than, for example, using explosives). When this was done, the extent of the defects found shocked even some of the activists, such as the architect Sam Webb, who had been lobbying for years that the building was unsafe.
September 13, 2019 at 07:42 #47132ClarkGerry, September 6 at 07:10 (#46919):
– “The North tower collapsed in about 13.8s total which equates to around 2/3 freefall, total freefall being approcx 9.2s for 1365ft. Still way too fast.”
Myself, September 6 at 16:04 (#46949)
– “Yes, the internal collapse accelerated at around 2/3 of g, so 1/3 of the entire potential energy of the structure (before collapse) was available for destruction of materials. Convert that to TNT equivalent and you can see that it was way more than enough.”
I agree that the collapse was much too fast to be consistent with Bažant’s “crush down then crush up” model. But Bažant’s model isn’t consistent with observation of either the collapse or the wreckage; it’s an interesting theoretical exercise, but it isn’t remotely realistic and it was never intended to be.
Bažant’s model is the failure mode that demands the most energy, bending every vertical column in the building. But when things break in the real world, they do so at the weakest points rather than the strongest, ie. they break in whatever way requires least energy. In the Twin Towers’ collapses, this was cascade destruction of/through the floor systems.
September 13, 2019 at 17:42 #47139ClarkHere’s a 29 minute video by news cameraman Mark LaGanga. Don’t bother if you prefer two-second sound-bites on a loop or eyes in pyramids overdubbed with a male voice choir; this doesn’t even have commentary:
https://www.youtube.com/watch?v=r3HRjSB99Dw
Starting just after the collapse of WTC2, he walks into the disaster zone, enters the damaged and mostly evacuated WTC7, and then takes some shots of WTC1 burning. He videos most of the collapse of WTC2 before getting caught in the dust cloud.
September 13, 2019 at 17:45 #47140Clark– He videos most of the collapse of
WTC2WTC1 before…Obviously.
September 13, 2019 at 19:58 #47141ClarkIn this video you can see the masses of wreckage – which didn’t exist, some Truthers tell me, because the buildings were “turned to dust”. At 03:15 you can see how insubstantial the Twin Towers’ perimeter structure looked once deprived of the illusion of solidity provided by the building before it was damaged. And these are just a few of the lower floors, yet some Truthers repeatedly insist that this structure could have supported itself upright to over ten times the height of the remnant shown, without lateral bracing from the floor systems.
September 13, 2019 at 22:55 #47142DaveThe expression the towers turned to dust is accurate, but you’re right some of it didn’t turn to dust, but reinforced iron, concrete and steel doesn’t turn to dust due to a shoddy build but can due to high grade explosives and the picture is an example of what material had been turned to dust.
September 14, 2019 at 09:00 #47149ClarkEven in a normal civilian controlled demolition, explosive or vérinage, most of the dust is produced by the material crushing itself as the collapse hits ground.
The WTC buildings produced more dust because the buildings were much taller than any buildings that have been imploded. There was further for the rubble to fall, so it picked up more speed, more kinetic energy, which was all dissipated in the final crush.
There’s really no mystery. When ore or rubble is deliberately turned to dust it is done by crushing it in a mill. This process has been studied thoroughly and is well quantified. The same equations have been applied to the Twin Towers’ collapses, and the amount of dust produced was normal.
September 14, 2019 at 09:21 #47150DaveExcept there was nothing being crushed, it was just exploding into dust, but as you rightly say some of the 220 stories of reinforced, concrete iron and steel didn’t turn to dust!
September 14, 2019 at 10:42 #47151ClarkJust watch the collapse videos. You can see the descending, accelerating front of dusty air ejected by the avalanche of concrete floor systems confined within the perimeter columns. It races ahead of the second wave of collapse (namely the toppling of perimeter sections), and the huge dust cloud wells out as it reaches ground. All just what you’d expect from progressive collapse of the concrete floor systems, all just as predicted by Newton’s laws.
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