Richard Gage Blueprint for Truth Rebuttals on YouTube by Chris Mohr

[pgimeno]

I've been reading several posts about factors of safety as I write this, for the answer to #7. I've seen these:

https://deeppoliticsforum.com/forums/showthread.php?7130-Safety-Factor-of-WTC-Steel-Columns (1.54, core, first floor)
http://www.internationalskeptics.com/forums/showthread.php?t=137095 (1.4, core)
http://www.internationalskeptics.com/forums/showthread.php?p=4517985#post4517985 (2.29, core)
http://the911forum.freeforums.org/post15486.html#p15486 - that's probably where the 5x factor comes from, but it's the only estimation I've found so far on the perimeter's FOS. Szamboti estimates the section and from it he estimates the FOS.

If we have to take these numbers as good, that gives another argument for #4: the FOS of the core was much less than that of the perimeter.

With that, I'll skip #7 for now until someone that knows better than me can give a better response than I would.

I'll also skip #8 as I don't know what does the "eccentric load on surviving means" argument mean.

#9 | Structural Damage Throughout Building | There was only structural damage on the top floors. The floors below were in perfect condition with their full strength, stronger towards the bottom. | I agree, with the clarification that the bottom ones also were more stressed as they bore more load.
#10 | Fast-moving Fires on all four faces in 15 minutes | Yes, they moved fast from one place to the other, and were going out fast too, from where they came from. | As with any other fire, they were going out fast where there was no fuel, and they remained longer where there was fuel.
#11 | Smoke quickly choking occupants on top floors | Yes, as the fire was starved for oxygen, there was mostly smoke. | Fire had quite some oxygen paths. The windows were blown by the fireball and impacts. The cores had elevators acting as chimneys. Oxygen sources were contemplated by NIST in their fire simulations.
#12 | 1000 Windows Break out; 12000 sq ft ventilation | Windows breaking out is an indication of an explosive force from within. | The deflagration of the jet fuel explains it without any hush-a-boom; the window breakage started at plane impact time and worsened with fires, and is documented over time. But the response supports that the reply to #11 was a no-go.
#13 | Explosions Radiating Every Direction | (snip) | (huh?)
#14 | 90,000 Liters of Jet Fuel | Regardless of the volume, the jet fuel burned off within the first 15 minutes. So what is the source of the "intense heat" after that? | The fires that the jet fuel initiated, obviously!
#15 | Fires Radiate to All Four Faces Within 15 Minutes | Yes, the fire migrated, but was not on all four faces simultaneously. They burned out enough that people could stand there, such as Edna Cintron. | Again, only in points where there was no remaining combustible material because it was moved or dragged by the plane impact.
#16 | Jet Fuel in Elevator Shafts | There is no evidence that jet fuel went down the elevator shafts to any great degree. The elevator doors would have been closed. The shafts are staggered and don't go all the way to the ground, except for the elevator for tourists. | Many reports confirm fuel went all the way down to the lobby and basement. Freight elevators also went all the way down. A big mass of fuel falling from that height could easily break the elevator doors. http://www.youtube.com/watch?v=FI7BHSOVtMs That could also explain many explosion reports.
#17 | Thermal limit of steel 750º | Edna Cinton and other WTC employees were standing in the spot where the plane entered the building. So there was no 750º heat for long. | Again, that place was freed of fuel for fires by the plane impact. See #6.
#18 | Leslie Robertson didn't design WTC for fuel explosion | The WTC was designed to withstand the impact of the largest airliner at the time. This includes seats, luggage, and fuel. Edna Cinton was standing at the site of the plane impact, so there was not such a hot flame. | No, Robertson was very clear saying that the effects of subsequent fires were not contemplated. In http://www.nae.edu/cms/Publications/TheBridge/Archives/7344.aspx he writes: "To the best of our knowledge, little was known about the effects of a fire from such an aircraft, and no designs were prepared for that circumstance. Indeed, at that time, no fireproofing systems were available to control the effects of such fires."
#19 | What We See Outside Is Small Part of Explosion | (snip) | (huh?)
#20 | Jet Fuel Explosions on 77th and 22nd Floor of Lobby from Elevator Shaft | (no comment) | (no comment either)
#21 | Fatal Fireball in Lobby Due to Elevator Fires | Fireman described lobby as looking like an explosion went off. Shrubbery in lobby showed no sign of flames. There was no driving force for fire (which rises) to go down 75+ floor. The elevator shafts in the WTC were staggered, so there was no direct access to the lobby. Fuel going down the shaft would decrease from the fuel needed to weaken the floors above. | (*)

(*) As for #21, here's what I've found:
http://sites.google.com/site/911stories/wtcelevatorshafts

There were at least two elevators (#6 and #7) that apparently shared the shaft and ran from top to the lobby, and at least one freight elevator (#50) that served all floors. Help confirming or clarifying this point would be appreciated.

Burning materials, even in liquid form, go down.

Since fuel didn't play a significant role on weakening the floors other than igniting the fires, the last point is moot.

That's all for now. I'll finish my take on the rest later. Everyone's welcome to refine or correct these or give better explanations or whatever. This is only *my* take.

 

[Christopher7]

I too agree that the NIST model did not perfectly reflect the reality of FFA for 2.25 seconds. Did it "represent the collapse with enough accuracy"? Here I disagree and say yes, it is enough accuracy

"That's close enough for government work" doesn't cut it. The NIST model falls at 40% slower than FFA. FFA is very significant because it means zero resistance for about 100 feet. But the NIST model provided enough resistance to noticeably slow the decent. The NIST model does not meet this critical parameter.

The high-strength steel has a much lower ductility, which must have caused fractures with a drop of axial force to zero very early during buckling, [...]

Must have? That is not data, it's an assumption, not evidence.

I have worked with steel and it does not snap like a stick. Your analogy is invalid until you can show a test by a credible source that confirms your assumption.

 

[pgimeno]

[ETA: forgot this part:

"That's close enough for government work" doesn't cut it.

What about "That's close enough for a building safety evaluation"?
end ETA]

Must have? That is not data, it's an assumption, not evidence.

"must have" as in "a ball must have fallen if you released it" even if you dropped it while blindfolded.

That quote comes from Bazant. He has a book on fracturing that he wrote with Planas in 1998. Here's the index: http://www.civil.northwestern.edu/people/bazant/PDFs/Papers/B4 Fracture and Size Effect.pdf and he cites that book to support the fracturing. Your argument, on the other hand, reduces to incredulity.

I have worked with steel and it does not snap like a stick. Your analogy is invalid until you can show a test by a credible source that confirms your assumption.

Have you worked with high-strength structural steel at room temperature?

These are not assumptions. They are based on data.

 

[sheeplesnshills]

Hi all,

Rick "Truth Makes Peace" is a 9/11 Truth activist who also actively supported the WTC dust study of Jim Millette (with both money and publicity in the 9/11 Truth movement). Now he is working with Richard Gage, Chris Sarns and others to put together a re-rebuttal of my 238 reasons for Natural Collapse listed in my YouTube video series (see my signatures below for links).

It's not completed yet, but here is a link to their responses to my rebuttals so far:
http://911theories.org/ChrisMohr or just chrismohr911.com

My 238 reasons are in the left column. Their responses are in the right column. People are encouraged to watch my video first (one at a time), then my reasons are rebutted by the 9/11 Truth side. This will be a big project, but I'd like to take this slowly and work on it one section at a time. For the re-re-rebuttal, I need to boil it down to one or two-liners, preferably with links. This is where some of alienentity and dave thomas and other YouTube videos could be linked, for example. So, for example, reason #1 I list the jets hitting at 450-550 mph and he has responded with Frank De Martini's claim of the building's strength. I might write in response, DeMartini died on 9/11 so we'll never know what he would say: [link] The link could be to a discussion of deMartini's claims, either YouTube or text.

In other words, very succinct. Respectful (tho some YouTube videos could be linked that are less than respectful if the info is good).

I'd love help with this. Please headline your suggestions with #1 Rebuttal or whatever and suggest a one-line response and links. In some ways I've already started this in the written Description part of each of my YouTube videos, where I now have a pretty good collection of links for more info.

For now I request that we work together on reasons 1-44 for awhile.

Thank you,
Chris

Well number one is bunk so thats not a good sign that they put any effort into this at all. The attached twoofer site (I love it when these guys debunk themselves) makes it quite clear that the 1975 fire in WTC1 was only on the 11th floor other than in a cabling duct from where it did not spread. It did not even burn all the 11th floor. In 1975 I think that floor of WTC1 had asbestos insulation which was newly applied and intact. There was no structural damage before the fire either and the columns at that level were much thicker than those at the impact points on 911 and so would heat up slower and conduct heat away much more effectively. Furthermore this fire was fought.
http://whatreallyhappened.com/WRHARTICLES/wtc_1975_fire.html

To compare that with the massive damage, and unfought fires over at least 10 floors at the same time on 911 is utterly ludicrous.



for # 5 Steel pans is a red herring as they are only there to contain the concrete when its poured, they played little, if any, structural part in the design. There is no doubt the insulation came off. It was a known problem with the building that it was falling off all by itself and was being replaced as floors were being renovated. The idea that it would stand up to the blasts of the impacts on 911 is just silly.

 

[chrismohr]

Chris,

Thank you for your acknowledgement of Rick's efforts.

Rick has been banned here and would like to be allowed to post here again. Perhaps you could ask the mods to reinstate his posting privileges. (I don't have a lot if influence around here ;-)

BTW: This is Rick's project, I'm just contributing things from the debates we have had.

* * * * * * * * * * *

Did Ron ever hear back from Dr. Lee? I have not.

Hi Chris7,
I have asked JREF to consider Rick's reinstatement on a probationary basis. No harm in asking, I'm still here even after making the request. And no, Ron has not heard back from Rich Lee.

 

[Justin39640]

"That's close enough for government work" doesn't cut it. The NIST model falls at 40% slower than FFA. FFA is very significant because it means zero resistance for about 100 feet. But the NIST model provided enough resistance to noticeably slow the decent. The NIST model does not meet this critical parameter.

Must have? That is not data, it's an assumption, not evidence.

I have worked with steel and it does not snap like a stick. Your analogy is invalid until you can show a test by a credible source that confirms your assumption.

I work with A LOT of steel and I can assure you, yes, sometimes it does. (think work hardening)

 

[pgimeno]

OK, last batch.

#22 | Inward Bowing of Perimeter Columns | There is no evidence that supports that fire alone could have caused this. Issue addressed in detail here: http://911debunkers.blogspot.com/2010/07/wtc-pre-collapse-bowing-debunks-911.html Points 22, 27 and 28 are quite similar | The fire was there and the inward bowing was there, first seen 18 minutes after impact in tower 2 and 1h 37 min. after impact in tower 1 (5 min. before collapse). NOTE: The "fire alone" argument is new to me. Is there a claim here that something else was used to gradually weaken the towers? I have not seen such a claim before. Can someone add to this? I think that the simulations support the sagging but I'm not sure. #23|Huge Temperature Differentials along Individual Beams <snip>|the jet fuel burned off within the first 15 minutes. So what is the source of the "intense heat" after that? <snip>| See #14. Let me add also the fire tests conducted by NIST (NCSTAR 1-5 et al, documenting building interior and combustibles).
#24 | Bright orange flames in tower: evidence of 1800 degree fires | Yes, so something other than jet fuel was burning. Jet fuel burns at only 500-599º F http://en.wikipedia.org/wiki/Jet_fuel | Agreed, it was something other than jet fuel. It was an office fire with office combustibles, see #23.
#25 | Major Fires in multiple floors; smoke rising hundreds of feet up | We differ on the word "major" fires. There were in the first minutes of the plane hitting. But the fires were burning out, causing smoke. Smoke is relatively cool, and has little impact on the steel and concrete. Indeed Edna Cintron and others were seen standing where the "major fires" supposedly were. | On the contrary, the fires got worse as time passed, see e.g. http://911research.wtc7.net/essays/st911/docs/wp_wtc29c.jpg or http://2.bp.blogspot.com/_rLV-ZuNPw...lEKQ/s1600/NorthTowerFireGJS-WTC27cropped.jpg and discussion on Edna Cintron in #6.
#26 | Lattice of Inward Buckling of Perimeter Columns by 55 Inches | (no comment) | (no comment either)
#27 | | | see #22
#28 | | | see #22
#29 | | | no comment either
#30 | | | no comment either
#31 | | | no comment either
#32 | At 10:28 a.m.: "the roof is going to come down very shortly" The North Tower collapsed seconds later. | The roof of the top 10-20 section of floors would collapse the next 10-20 floors, but not the 70-80 floors below. That's a misunderstanding of how collapses happen in the real world. The top 10-20 section of floors would make the next floor collapse; then the top 11-21 section of floors wold make the next floor collapse, then the 12-22 section of floors ... all the way to the bottom, adding weight at every step.
#33 | Richard Gage claims that near the end, "The fires were diminishing severely." But they grew from 3 to 14 floors in less than an hour. | Fireman reported "We've got two isolated pockets of fire! We should be able to knock it down with two lines." http://www.youtube.com/watch?v=nU1WqEYEMBQ | Yes, that happened in floor 78 of WTC2, where indeed the NIST report shows two isolated pockets of fire. The inferno was in the floors above floor 78.
#34 | | | no comment either
#35 | If thermites at the top, then no one could have walked on the debris pile | Even steel toed boots were melting within hours at Ground Zero at 1100º degrees. http://www.youtube.com/watch?v=XGa1YWK1-1E | (*)
#36 | | | no comment either
#37 | | | no comment either
#38 | Smoke and dust had no significant upward velocity | Videos show steel beams and concrete dust ejected upwards and outwards at speeds about 60 miles per hour. | The videos don't show such thing. They show dust being ejected from the building downwards (but the faster downward movement of the building makes it look as if it went upwards). They also show aluminium cladding flying, not columns.
#39 | | | no comment either
#40 | They took the towers down using demolition charges on the roof? | This is not a main stream 9/11 Truth hypothesis. Perhaps some were on the roof. But most Truthers posit that demolition charges were placed on many floors in the World Trade Center, possibly every floor, then detonated in sequence by wireless computer control. (**)
#41 | | | no comment either
#42 | | | no comment either
#42a | | | no comment either
#43 | NIST: "No building in the United States has ever been subjected to the massive structural damage and concurrent multi-floor fires that the towers experienced on Sept. 11." | The North Tower's impact was so high -- just 15 lightweight stories from the top -- that no amount of structural damage to that portion of the core would threaten the whole building. The South Tower's core columns apparently escaped significant damage. Issue addressed in detail here: http://911research.wtc7.net/wtc/analysis/official/columns.html Excepting the three 9-11 collapses, no fire, however severe, has ever caused a steel-framed high-rise building to collapse. Following are examples of high-rise fires that were far more severe than those in WTC 1 and 2, and Building 7. 911research.wtc7.net/wtc/analysis/compare/fires.html | They were not far more severe. Not really comparable, as they had the thermal insulation in place and the fires were fought. No surprise then that it was the first time such a collapse happened: the few comparable cases didn't have a remotely similar structure to any of the three buildings. In other steel building fires such as WTC5 and One New York Plaza there were internal floor collapses, and it was just luck that that didn't cause the buildings to completely collapse.
#44 | 13 Story High Façade... Why Didn't Nanothermites Pulverize This? | At the bottom of the WTCs, there probably was no need for explosives.| Neither at the top.

(*) On #35: I'll leave this one for someone else.
(**) On #40: No idea what to say for this one either. I don't know where does the thermite on the roof idea come from to start with.

 

[ozeco41]

...I'd love help with this. Please headline your suggestions with #1 Rebuttal or whatever and suggest a one-line response and links. In some ways I've already started this in the written Description part of each of my YouTube videos, where I now have a pretty good collection of links for more info.

For now I request that we work together on reasons 1-44 for awhile.

Thank you,
Chris

Chris - I acknowledge pgimeno has done a lot of work making the tables and he has invited others to refine his comments:

... Everyone's welcome to refine or correct these or give better explanations or whatever. This is only *my* take.

- so I will take the lazy way and add another column:

#0 | ChrisMohr | AE911 response | pgimeno comment | ozeco41 additional comment
#1|Planes Hitting at 450-550 mph|Frank DiMartini, Construction Manager of the WTC, said it was designed to withstand a fully loaded plane impacting, even several. http://www.youtube.com/watch?v=1pvEge5HPJU Planes hitting their targets so accurately, at such speeds, by beginner alleged pilots, suggest computer assisted remote control should be investigated. | The buildings did withstand the impacts, despite being calculated for a lower speed impact. The buildings were approximately the width of a runway, so it didn't need a lot of skill to hit them by people who knew how to land, yet one of the hits was sloppy.|Agree with pgimeno PLUS investigating remote control is a red herring. Impact of the actual planes observed by witnesses.
#2 |Planes steeply banked, max damage | Wings tilted, distribute damage across several floors, enabling more supports to remain on each floor| (I don't think that the tilt was a factor anyway)| The "more supports remaining.." is engineering nonsense. Collapse initiation resulted from a combination of mechanisms. the tilt over three or so floors still meant that the peripheral columns were cut in the impact zone of several floors. It matters not which floor the cut was in.
#3 |282,000-lb Planes |See #1: Frank DiMartini WTC 1 and 2 withstood impact and stood for about 1 hour| See #1.| So what? What point is being made?
#4 | 60% of columns on crash side destroyed | Only the exterior walls. The inner core was not damaged significantly, which bore most of the weight. | Damage to the core's fireproofing due to the impact had to be necessarily significant.| The hinted at engineering issue here is that these lay persons do not understand load distribution/redistribution. It is not a matter of linear re-allocation such that (say) 25% columns cut uniformly increases remaining column loadings by 33%. Explanations posted several times previously - can explain more BUT we are writing for a lay audience and it is moderately complex engineering.
#5 | Fire Insulation Stripped Off | Steel pans don't melt, even with no insulation It is debatable whether or not the insulation was stripped of significantly. The towers fell, obfuscating the evidence. No one knows for sure. | Steel didn't need to melt in order to be weakened to the point of being unable to bear the building. NIST conducted conservative simulations to determine the damage to the core insulation.| There were two lots of insulation that were critical. Floor joist insulation where it is ludicrous to suggest not stripped off after a falling apart large aircraft had bulldozed itself and all the office partitions and contents across the impact zone. Core column insulation ditto.
#6 | Cutoff of Water Sprinklers | The cutoff of the water sprinklers is suspicious, considering that the WTCs were carefully designed so they would work. Regardless, the fires went out, even without water. We see people, including Edna Cinton, standing where the fires started. | No sprinkler system is designed against loss of pressure due to a plane cutting the pipes. The fires didn't start at the point of the impact; the fireball was immense and covered a big part of each building, so they started in many places at the same time. The planes moved the burning materials towards the opposite side of the building, that's why the fires didn't last long at the hole where Edna was seen.| All four claims are nonsense - don't need to add anything.

 

[ozeco41]

My Part #2 - thanks again for pgimeno setting up the table.

#0 | ChrisMohr | AE911 response | pgimeno comment | ozeco41 additional comment
#7|Collapse Safety Factor of 3 Reduced|WTC was built to support 5 times, not 3 times the load, on the perimeter columns.||There is an implicit misunderstanding of FOS and how it interacts with load redistribution. Moderately complex engineering involved - see my previous comment at Item 4 in previous post.
#8 | Eccentric Load on Surviving Beams |The surviving beams, those that were not hit by the plane, were still strong enough to bear the weight of the floors above, for about an hour for both WTC 1 and 2.||Yes, but... (I am presuming we mean "columns" here - "beams" does not make sense) The remaining undamaged columns were sufficient to support immediately after the impact. They deteriorated due to fire damage. The AE911 comment misses the point.
#9 | Structural Damage Throughout Building | There was only structural damage on the top floors. The floors below were in perfect condition with their full strength, stronger towards the bottom. | I agree, with the clarification that the bottom ones also were more stressed as they bore more load.| The strength of the lower tower is not relevant. The mechanism of collapse progression is well understood. It bypassed the strength of the columns which is why it was so fast. The three key mechanisms were "ROOSD"; core cross beam strip down and outer perimeter peel-off. Mostly avoiding column strength. The implicit claim that the "full strength" was available is false.
#10 | Fast-moving Fires on all four faces in 15 minutes | Yes, they moved fast from one place to the other, and were going out fast too, from where they came from. | As with any other fire, they were going out fast where there was no fuel, and they remained longer where there was fuel.| So what?:
#11 | Smoke quickly choking occupants on top floors | Yes, as the fire was starved for oxygen, there was mostly smoke. | Fire had quite some oxygen paths. The windows were blown by the fireball and impacts. The cores had elevators acting as chimneys. Oxygen sources were contemplated by NIST in their fire simulations.| Mostly red herring and untrue interpretation. The issue is that the fires were hot enough and extensive enough to do the necessary damage.
#12 | 1000 Windows Break out; 12000 sq ft ventilation | Windows breaking out is an indication of an explosive force from within. | The deflagration of the jet fuel explains it without any hush-a-boom; the window breakage started at plane impact time and worsened with fires, and is documented over time. But the response supports that the reply to #11 was a no-go. | Agree with pgimeno
#13 | Explosions Radiating Every Direction | Yes, explosions radiating in every directions means explosives were used. For sounds of explosions this should be used: http://www.ae911truth.org/news-section/41-articles/574-faq-7.html | (huh?)| False claim "explosions" =/= "explosives"
#14 | 90,000 Liters of Jet Fuel | Regardless of the volume, the jet fuel burned off within the first 15 minutes. So what is the source of the "intense heat" after that? | The fires that the jet fuel initiated, obviously!| agreed with pgimeno
#15 | Fires Radiate to All Four Faces Within 15 Minutes | Yes, the fire migrated, but was not on all four faces simultaneously. They burned out enough that people could stand there, such as Edna Cintron. | Again, only in points where there was no remaining combustible material because it was moved or dragged by the plane impact.
#16 | Jet Fuel in Elevator Shafts | There is no evidence that jet fuel went down the elevator shafts to any great degree. The elevator doors would have been closed. The shafts are staggered and don't go all the way to the ground, except for the elevator for tourists. | Many reports confirm fuel went all the way down to the lobby and basement. Freight elevators also went all the way down. A big mass of fuel falling from that height could easily break the elevator doors. http://www.youtube.com/watch?v=FI7BHSOVtMs That could also explain many explosion reports.| all the bits of sub-claims false.
#17 | Thermal limit of steel 750º | Edna Cinton and other WTC employees were standing in the spot where the plane entered the building. So there was no 750º heat for long. | Again, that place was freed of fuel for fires by the plane impact. See #6.| Agreed - it's a red herring
#18 | Leslie Robertson didn't design WTC for fuel explosion | The WTC was designed to withstand the impact of the largest airliner at the time. This includes seats, luggage, and fuel. Edna Cinton was standing at the site of the plane impact, so there was not such a hot flame. | No, Robertson was very clear saying that the effects of subsequent fires were not contemplated. In http://www.nae.edu/cms/Publications/TheBridge/Archives/7344.aspx he writes: "To the best of our knowledge, little was known about the effects of a fire from such an aircraft, and no designs were prepared for that circumstance. Indeed, at that time, no fireproofing systems were available to control the effects of such fires."|pgimeno is correct
#19 | What We See Outside Is Small Part of Explosion | http://www.youtube.com/watch?v=i3MN9382eGY 1:17 Numerous testimonies about explosions | (huh?)|Same "explosions" =/= "explosives" canard.
#20 | Jet Fuel Explosions on 77th and 22nd Floor of Lobby from Elevator Shaft | (no comment) | (no comment either)| No comment needed - Chris's claim of fact is uncontested.
#21 | Fatal Fireball in Lobby Due to Elevator Fires | Fireman described lobby as looking like an explosion went off. Shrubbery in lobby showed no sign of flames. There was no driving force for fire (which rises) to go down 75+ floor. The elevator shafts in the WTC were staggered, so there was no direct access to the lobby. Fuel going down the shaft would decrease from the fuel needed to weaken the floors above. | (*)| Nonsense. Fuel falls and the structural claims about the shafts/elevator doors are wrong.

...Burning materials, even in liquid form, go down.

Since fuel didn't play a significant role on weakening the floors other than igniting the fires, the last point is moot...

Agreed to both.

 

[pgimeno]

The hinted at engineering issue here is that these lay persons do not understand load distribution/redistribution. It is not a matter of linear re-allocation such that (say) 25% columns cut uniformly increases remaining column loadings by 33%. Explanations posted several times previously - can explain more BUT we are writing for a lay audience and it is moderately complex engineering.

tfk gave in another thread an example with a four leg chair to which you cut a leg. I don't know if he elaborated, probably not, but it was quite clear to me what he talked about.

If you are sitting on a four leg chair and cut one leg, one of the remaining legs clearly bears almost no load while the other two bear almost the rest of the weight. You can recenter your ass in the chair so as to distribute the loads more equally, but in the case of a building the load can't move.

I think that explanation is accessible enough for many people.

 

[pgimeno]

Oops, correction for my #32 which came out confusing because I forgot a separator in the table:

#32 | At 10:28 a.m.: "the roof is going to come down very shortly" The North Tower collapsed seconds later. | The roof of the top 10-20 section of floors would collapse the next 10-20 floors, but not the 70-80 floors below. | That's a misunderstanding of how collapses happen in the real world. The top 10-20 section of floors would make the next floor collapse; then the top 11-21 section of floors wold make the next floor collapse, then the 12-22 section of floors ... all the way to the bottom, adding weight at every step.

 

[ozeco41]

UOT

My part #3 - thanks again to pgimeno for doing the tedious work of formatting the table

#22 | Inward Bowing of Perimeter Columns | There is no evidence that supports that fire alone could have caused this. Issue addressed in detail here: http://911debunkers.blogspot.com/2010/07/wtc-pre-collapse-bowing-debunks-911.html Points 22, 27 and 28 are quite similar | The fire was there and the inward bowing was there, first seen 18 minutes after impact in tower 2 and 1h 37 min. after impact in tower 1 (5 min. before collapse). NOTE: The "fire alone" argument is new to me. Is there a claim here that something else was used to gradually weaken the towers? I have not seen such a claim before. Can someone add to this? I think that the simulations support the sagging but I'm not sure. | The implied issue is the canard that sagging floor joist trusses would not cause the full inwards bowing as observed. A partial truth. The sagging only had to start the inwards bowing and it would continue to bow further by itself as normal column buckling under the applied axial load.
#23|Huge Temperature Differentials along Individual Beams <snip>|the jet fuel burned off within the first 15 minutes. So what is the source of the "intense heat" after that? <snip>| See #14. Let me add also the fire tests conducted by NIST (NCSTAR 1-5 et al, documenting building interior and combustibles).| The heat energy came from the office materials/contents - the jet fuel's role was to near instantaneously start large fires on several floors. It was the initiator.
#24 | Bright orange flames in tower: evidence of 1800 degree fires | Yes, so something other than jet fuel was burning. Jet fuel burns at only 500-599º F http://en.wikipedia.org/wiki/Jet_fuel | Agreed, it was something other than jet fuel. It was an office fire with office combustibles, see #23. | answered by pgimeno
#25 | Major Fires in multiple floors; smoke rising hundreds of feet up | We differ on the word "major" fires. There were in the first minutes of the plane hitting. But the fires were burning out, causing smoke. Smoke is relatively cool, and has little impact on the steel and concrete. Indeed Edna Cintron and others were seen standing where the "major fires" supposedly were. | On the contrary, the fires got worse as time passed, see e.g. http://911research.wtc7.net/essays/st911/docs/wp_wtc29c.jpg or http://2.bp.blogspot.com/_rLV-ZuNPw...lEKQ/s1600/NorthTowerFireGJS-WTC27cropped.jpg and discussion on Edna Cintron in #6.| no further comment needed.
#26 | Lattice of Inward Buckling of Perimeter Columns by 55 Inches | (no comment) | (no comment either)| My previous comments apply.
#27 | Sagging Steel, Inward Bowing Breaks Connection |There is no evidence that supports that fire alone could have caused this. Issue addressed in detail here:_ http://911debunkers.blogspot.com/2010/07/wtc-pre-collapse-bowing-debunks-911.html __Points 22, 27 and 28 are quite similar | see #22| Outright denial. See also my previous comment which addresses the usual truther canard. The referenced "blogspot" link does not address the issues. More details if needed.
#28 | | | see #22|
#29 | | | no comment either|
#30 | | | no comment either|
#31 | | | no comment either|
#32 | At 10:28 a.m.: "the roof is going to come down very shortly" The North Tower collapsed seconds later. | The roof of the top 10-20 section of floors would collapse the next 10-20 floors, but not the 70-80 floors below.| That's a misunderstanding of how collapses happen in the real world. The top 10-20 section of floors would make the next floor collapse; then the top 11-21 section of floors wold make the next floor collapse, then the 12-22 section of floors ... all the way to the bottom, adding weight at every step.|The original comment shows no comprehension of the actual collapse mechanism. I think it is better to give the full "three mechanisms" explanation. viz ROOSD + core strip down + perimeter peel off. We know those three to be demonstrated fact. So the vagueness of "make the next floor collapse" looks like we don't understand what actually happened. Plus it wasn't "floor by floor" for the whole building - not even floor by floor for ROOSD which happened in zones at differing rates for different sides of each tower. Perimeter peel off was much later than "floor by floor". And I don't think anyone has timed the core strip down process.
#33 | Richard Gage claims that near the end, "The fires were diminishing severely." But they grew from 3 to 14 floors in less than an hour. | Fireman reported "We've got two isolated pockets of fire! We should be able to knock it down with two lines." http://www.youtube.com/watch?v=nU1WqEYEMBQ | Yes, that happened in floor 78 of WTC2, where indeed the NIST report shows two isolated pockets of fire. The inferno was in the floors above floor 78.| Another long rebutted canard.
#34 | | | no comment either
#35 | If thermites at the top, then no one could have walked on the debris pile | Even steel toed boots were melting within hours at Ground Zero at 1100º degrees. http://www.youtube.com/watch?v=XGa1YWK1-1E | (*)| I doubt the validity of the claim BUT "So what?" - is this an implied claim for thermXte use in CD? If so they should put their case not simply rely on innuendo.
#36 | | | no comment either
#37 | | | no comment either
#38 | Smoke and dust had no significant upward velocity | Videos show steel beams and concrete dust ejected upwards and outwards at speeds about 60 miles per hour. | The videos don't show such thing. They show dust being ejected from the building downwards (but the faster downward movement of the building makes it look as if it went upwards). They also show aluminium cladding flying, not columns.| again pgimeno is correct
#39 | | | no comment either
#40 | They took the towers down using demolition charges on the roof? | This is not a main stream 9/11 Truth hypothesis. Perhaps some were on the roof. But most Truthers posit that demolition charges were placed on many floors in the World Trade Center, possibly every floor, then detonated in sequence by wireless computer control. (**)| we should not accept "reverse burden of proof" to "prove a negative" BUT the mechanism of global collapse is well understood as per my several previous comments and CD was not needed. The only two stages where CD claims could possible be made - no one has made them - are pre weakening of core and in the impact zone assisting "initiation".
#41 | | | no comment either
#42 | | | no comment either
#42a | | | no comment either
#43 | NIST: "No building in the United States has ever been subjected to the massive structural damage and concurrent multi-floor fires that the towers experienced on Sept. 11." | The North Tower's impact was so high -- just 15 lightweight stories from the top -- that no amount of structural damage to that portion of the core would threaten the whole building. The South Tower's core columns apparently escaped significant damage. Issue addressed in detail here: http://911research.wtc7.net/wtc/analysis/official/columns.html Excepting the three 9-11 collapses, no fire, however severe, has ever caused a steel-framed high-rise building to collapse. Following are examples of high-rise fires that were far more severe than those in WTC 1 and 2, and Building 7. 911research.wtc7.net/wtc/analysis/compare/fires.html | They were not far more severe. Not really comparable, as they had the thermal insulation in place and the fires were fought. No surprise then that it was the first time such a collapse happened: the few comparable cases didn't have a remotely similar structure to any of the three buildings. In other steel building fires such as WTC5 and One New York Plaza there were internal floor collapses, and it was just luck that that didn't cause the buildings to completely collapse.| I would not rely on showing the analogies to be false. The claims about "impact was so high -- just 15 lightweight stories from the top -- that no amount of structural damage to that portion of the core would threaten the whole building" show denial of reasoned explanations. The comment conflates "initiation" with "progression" Once collapse was "initiated" i.e. the top block started to move downwards there was nothing to stop it once ROOSD was under way as the primary process of collapse progression. Also the false premise that strength of core columns was relevant - it wasn't in progression. It was overcome by a cascade failure in initiation. Then the "it's never happened before" argument from incredulity needs no comment by me.
#44 | 13 Story High Façade... Why Didn't Nanothermites Pulverize This? | At the bottom of the WTCs, there probably was no need for explosives.| Neither at the top.| They got one right!!! Except for the cop-out "probably"

(*) On #35: I'll leave this one for someone else.

even if the claim is true it's a "So what?" - what are they trying to claim? Why not make the claim rather than rely on innuendo?

..(**) On #40: No idea what to say for this one either. I don't know where does the thermite on the roof idea come from to start with.

Let it pass - if they want to make a claim let them make it. Not our job to accept "burden of disprove a negative" for an unmade claim.

 

[Christopher7]

Hi Chris7,
I have asked JREF to consider Rick's reinstatement on a probationary basis. No harm in asking, I'm still here even after making the request. And no, Ron has not heard back from Rich Lee.

Chris,

Thanks for asking. I'll pass that on to Rick.

TFC Thanks for the FYI.

C7

 

[ozeco41]

tfk gave in another thread an example with a four leg chair to which you cut a leg. I don't know if he elaborated, probably not, but it was quite clear to me what he talked about.

If you are sitting on a four leg chair and cut one leg, one of the remaining legs clearly bears almost no load while the other two bear almost the rest of the weight. You can recenter your ass in the chair so as to distribute the loads more equally, but in the case of a building the load can't move.

I think that explanation is accessible enough for many people.

Good one. The fact that redistribution follows the "para section modulus layout" of the remaining columns is not the easiest concept to put across for a general audience.

The problem is not just getting the concept across but then having people apply it in their thinking. It is second nature to structural engineers but we have been using it all our careers and naturally translated into every day experiences. Even in the simplest form of understanding leverage.

I have addressed the same issue in "text graphics" in a very similar setting to tfk's four leg analogy. I'll see if I can find the clip.

 

[ozeco41]

Oops, correction for my #32 which came out confusing because I forgot a separator in the table:

Thanks - I had missed the formatting error and carried it over into my post.

Now corrected.

 

[Clayton Moore]

Oops, correction for my #32 which came out confusing because I forgot a separator in the table:

#32 | At 10:28 a.m.: "the roof is going to come down very shortly" The North Tower collapsed seconds later. | The roof of the top 10-20 section of floors would collapse the next 10-20 floors, but not the 70-80 floors below. | That's a misunderstanding of how collapses happen in the real world. The top 10-20 section of floors would make the next floor collapse; then the top 11-21 section of floors wold make the next floor collapse, then the 12-22 section of floors ... all the way to the bottom, adding weight at every step.

Yet the most all of the rubble was pulverized into bits. Bits splay and lose their mass and directional weight.

The bits had weight but the weight would not have been effective to cause subsequent lower floors to collapse. If anything the bits would disperse and
lessen the force of the contact.

 

[pgimeno]

Thanks - I had missed the formatting error and carried it over into my post.

Now corrected.

Yet another at #40, sorry I forgot the separator before the (**) and your text came in the wrong column.

 

[pgimeno]

Yet the most all of the rubble was pulverized into bits. Bits splay and lose their mass and directional weight.

The bits had weight but the weight would not have been effective to cause subsequent lower floors to collapse. If anything the bits would disperse and
lessen the force of the contact.

Oh, no, not again. Ergo, Szamboti and now Moore. Why is this concept so difficult to understand?

Mass does not vary with fragmentation. At all. Being loose might cushion the impacts somewhat, at best, but the rubble would still be able to crush floors because even with the cushioning, the increase of load would not be slow enough for it to be absorbed. [ETA: Less so if the structural elements the rubble lands on are not designed to withstand such mass. Like floors.] Just as a snow avalanche crushes a house, for example.

 

[Christopher7]

Rick won't be allowed back. Just FYI.

He says he was not given a reason FWIW.

 

[Sunstealer]

I have worked with steel and it does not snap like a stick. Your analogy is invalid until you can show a test by a credible source that confirms your assumption.

You may have worked with steel but your experience and knowledge of it is close to zero.

I can take a piece of steel and heat treat it so that it snaps like a stick. I can take the exact same piece and heat treat it so that it's ductile and doesn't.

Infact I can take a piece of steel and under certain conditions it will fracture in a brittle manner like a stick and in others it will bend and absorb the same force without breaking. See "ductile to brittle transition" in steels.

Stop talking out of your behind.