Size of "the Pile"

[DannyBoy2k]

I know that I have, somewhere, seen a quote on how big the "Pile" after the collapse of the towers were, but I cannot for the life of me find it. Something tells me it was here, but I might be completely wrong.

So, does anyone know of a quote of area, height, what-have-you of the remains of the buildings?
Might not be the place here, but I can't think of any other place to ask either, so...

 

[SR1419]

So, does anyone know of a quote of area, height, what-have-you of the remains of the buildings?
Might not be the place here, but I can't think of any other place to ask either, so...

Dont know exactly...but there have been a few threads about it. Such as:

https://www.metabunk.org/rubble-piles-relative-size-for-wtc-1-and-2.t8230/#post-197194

 

[investigating911]

Recently this photo of the corner of west and liberty street just southwest of the south facade of the collapsed south tower was featured in the story https://abcnews.go.com/US/domestic-terrorist-styled-patriots-led-lethal-plot/story?id=80303614

The photo was taken on the evening of September 12, 2001, so just a bit more than a day after the 9/11 attack and collapse of the towers, so presumably before most of the surrounding WTC debris on West and Liberty Streets had been cleaned up.

The most heavy-weight debris (the bulkier steel columns, compressed and mangled floors, and elevator motors) appear to remain close to the footprint of the tower, but piles of lighter-weight material like aluminum cladding, twisted piping and lightweight steel trusses are much farther from the footprints, although you cannot see clearly where street level starts except for the outline of the south tower exterior columns (defining the former lobby levels, as were seen prior to the collapses in the photo below)



in the background because of how the debris is obstructing view of the underlying street. The picture pre collapse shows the Greek Orthodox Church, which was 250 feet south of the south tower (https://untappedcities.com/2015/09/...k-about-wtc-tight-roper-gets-geography-wrong/), so it can be assumed that the surviving footbridge was just a few feet farther away radially. From the surviving south footbridge in the left of the top-most image, I would guess that the debris is at least shin deep on Liberty Street just south of the collapsed south tower.



Figure 1-7 from Chapter 1 of the World Trade Center Building Performance Study https://www.fema.gov/pdf/library/fema403_ch1.pdf


Interestingly, the debris is not more than ankle deep at most just a bit more distance away from that on West Street - see 3:32 in Source: https://www.youtube.com/watch?v=3pa47YOqeYE

- however this is possibly explained by how most of the material in south tower fell to the east and north of the footprint and not to the west or southwest where the corner of West Street and Liberty Street is in relation to the south tower.

From what I understand, within the bathtub region, the debris collapsed down to basement level and in some cases the bedrock, leaving a pile a few stories high above that for all the debris that settled on top of that. Where there was no steel cage bathtub structure underneath (such as on and near West and Liberty Street), the debris did not seem to fall into any available voids but instead either punctured the road surface or was lain on top of the relatively unyielding surface when it came to rest.

For the falling debris in and near the tower footprints located within the bathtub, the falling steel columns would have collapsed the underlying steel in the bathtub, and the heavier debris would collect there and then pile up above street level.

For the falling steel columns that fell onto the street in the area not contained in the bathtub, my guess is that the columns would either get lodged into the street (like it did for the exterior column spokes on West Street and Church Street - see 2:54 in the previously mentioned video Source: https://www.youtube.com/watch?v=3pa47YOqeYE
, and 0:07 and 1:17 in the following video
Source: https://www.youtube.com/watch?v=Wch6XB6xr2g
- or simply bounce off and come to rest at little while later when they stop bouncing off the surface (doing damage to the street in the process and producing crushed gravel and asphalt but not necessarily puncturing it).

Since the unyielding street level outside of the bathtub (specifically West Street and corner of Liberty Street close to the south footbridge) was farther away from the tower's footprints and most of the large, heavy debris from both towers seemed to fall onto the plaza region within the bathtub area (with only sections of outer perimeter wall peeling away and falling onto West and Liberty Street being the exceptions) rather than the south footbridge area, imo it's not too surprising that the amount of debris that piled up on West Street and Liberty Street was not as much as elsewhere in the ruined complex.

 

[Marc Powell]

I am not sure why you are perseverating on this issue. Much of what you speculate may indeed be true. However, photographic evidence confirms that loose debris and large sections of exterior column panels rained down in a symmetrical pattern around the footprint of each tower.

 

[investigating911]

I am not sure why you are perseverating on this issue. Much of what you speculate may indeed be true. However, photographic evidence confirms that loose debris and large sections of exterior column panels rained down in a symmetrical pattern around the footprint of each tower.

The photographic evidence (prior to most of the debris being cleaned up on the surrounding streets) appears to show a sharp gradient in the height of the debris pile with distance away from the footprints of the towers, which isn't surprising.
https://publicintelligence.net/911-ground-zero-damage-overview-high-resolution-photos/

However, what is notable is that the depth of the debris seems at least a few feet less deep southwest of the footprint of the south tower than elsewhere around the footprints of the towers.

This is not to say that there wasn't heavy debris pile up enough to cover the height of an average person around all sides of of the footprint of each tower, but it seems that most of the heavy debris fell onto the plaza level just 10 or 20 feet away from the facade remains, where it piled up notably in some areas (at least 10 to 50 feet high) above street level, while it was more spread out and less deep southwest of the footprint of the south tower, which didn't seem to be the case elsewhere around the footprints of the towers.


Image of debris pile at west face of the south tower extending up more than 10 feet above ground and up to 70 feet below grade.

Maybe that's because the plaza level just overlapped with the area where a larger volume of the heaviest debris fell, although Figure 1-7 from the FEMA World Trade Center Building Performance Study indicates that the heaviest debris fell even in the south footbridge area.



The following images (night of September 12, 2001 and night of September 17, 2001, respectively)




show that debris near the southwest corner of the remains of the south tower has not piled up very deep above street level (maybe only a few feet (perhaps up to 10 feet at the base of the south face of the south tower remains at most)), as the outline of part of the lowest lobby windows is still visible. A picture of the southern lobby of the south tower taken prior to 9/11 shows that the height of the lobby entrance doors was likely not more than 10 feet, although I can't find exact measurements of the height of the lower lobby windows and entrance doors.





The most confusing part of determining the height of the debris pile visually imo is that not all parts around the footprints of the towers were at the same elevation prior to collapse (there was the lower street level and the elevated plaza level) and that there were places outside of the bathtub where the underlying ground didn't give way, with the debris instead spreading out more laterally instead of piling up more vertically. Also caverns around the footprints of the towers made it difficult to ascertain what the height of the debris above ground level (the ground level defined as the plaza level prior to the collapse and caving in of the plaza) would be in those locations just outside of the footprints.


EarthData, LIDAR September 17, 2001 from the OEM/EMDC with scale on bottom-right showing elevation range.

Visually it appears that the debris pile generated by the south tower collapse was more lopsided, whereas the debris pile generated by the north tower collapse was more symmetrical. Given the lopsided way the south tower collapsed as opposed to the more symmetrical top-down manner that the north tower collapsed though, this isn't too surprising.

I've noticed that a lot of the pictures contesting the size of the debris pile that "should have been" generated come from West Street after a significant portion of WTC debris was already removed and the southwest edge of the south tower. A large portion of the heaviest debris falling away from the southwest side of the south tower footprint might explain why the debris isn't as deep as might be expected southwest of the south tower footprint.

 

[Marc Powell]

And the point of all your observations and speculations is what exactly?

 

[investigating911]

And the point of all your observations and speculations is what exactly?

I don't think that the debris pile generated by the south tower collapse was symmetric compared to the debris pile generated by the north tower collapse, which I think may explain why in some areas (especially to the southwest of the south tower footprint) it seemed like the debris pile was too shallow. Unless there is some other reason why there doesn't appear to be a significant depth of debris southwest of the south tower footprint?

 

[Gamolon]

I don't think that the debris pile generated by the south tower collapse was symmetric compared to the debris pile generated by the north tower collapse, which I think may explain why in some areas (especially to the southwest of the south tower footprint) it seemed like the debris pile was too shallow.

What does the debris pile being too shallow indicate that you are trying to find answers as to why?

 

[Nada Truther]

Unless there is some other reason why there doesn't appear to be a significant depth of debris southwest of the south tower footprint?

Are you insinuating that there is some OTHER more Nefarious reason? What reason would there be that the pile of debris would be smaller, other than "it didn't fall there"? I would love to hear some theories!!

 

[Marc Powell]

I don't think that the debris pile generated by the south tower collapse was symmetric compared to the debris pile generated by the north tower collapse, which I think may explain why in some areas (especially to the southwest of the south tower footprint) it seemed like the debris pile was too shallow. Unless there is some other reason why there doesn't appear to be a significant depth of debris southwest of the south tower footprint?

A large section of exterior column panels from the south side of the South Tower peeled away toward the southwest. It fell diagonally across the northbound lanes of West Street narrowly missing the building at 90 West Street and the Liberty Street Pedestrian Bridge, while squashing the Saint Nicholas Greek Orthodox Church. It can be seen through the smoke and dust in this picture taken shortly after the collapse:

Because clearing roadways was a priority in the days immediately after 9/11, few pictures exist showing debris in this area. Perhaps this information will put to rest the idea that the distribution of debris around the South Tower was not concentric about the tower footprint and that the depth of debris to the southwest was "too shallow."


Edit: Replaced photo with enhanced version having higher contrast.

 

[econ41]

And the point of all your observations and speculations is what exactly?

I still cannot see any definion of the objective - what is the purpose of this current "discussion"?

 

[Rory]

Following the link in the second post, it seems that a truther five years ago objected that "gravity alone couldn't have caused such a compact pile" (and I'm guessing it's something other truthers have said elsewhere and so part of their discussions).

Talk about clutching at straws.

 

[econ41]

Following the link in the second post, it seems that a truther five years ago objected that "gravity alone couldn't have caused such a compact pile" (and I'm guessing it's something other truthers have said elsewhere and so part of their discussions).

Yes. But simply get the Burden of Proof round the right way. The collapse did cause the pile of debris and associated scatter that we saw. So what? The possible truther claims range from "I a truther don't believe it!" Which is your problem MrTruther. Way out to the sublimely ridiculous "The heap isn't big enough so it must have been caused by CD!". And nobody but a truther could make that quantum leap of illogic. Somehow triggering a collapse by explosive cutting produces less steel debris than the same beams failing from heat weakening???

 

[Jeffrey Orling]

The towers were 95% or thereabouts air. The facade mass peeled away... So if the building's materials... were neatly stacked on the foot print it would be a block of "stuff" about 5% the height of the towers... or less than 6 stories tall. But dustified concrete and materials were scattered for blocks around the towers... so that compact block would be no more than a story, And then there were 7 levels below grade to fill up with collapsed debris.
There was inherently nothing unusual about the debris pile.

 

[Ѧρσ$†l£ѴڃrDɜ]

Yes. But simply get the Burden of Proof round the right way. The collapse did cause the pile of debris and associated scatter that we saw. So what? The possible truther claims range from "I a truther don't believe it!" Which is your problem MrTruther. Way out to the sublimely ridiculous "The heap isn't big enough so it must have been caused by CD!". And nobody but a truther could make that quantum leap of illogic. Somehow triggering a collapse by explosive cutting produces less steel debris than the same beams failing from heat weakening???

The Judy Wood disciples usually start with this premise, because in their scenario, the Twin Towers were vaporized (excuse me, "dustified") by some mysterious technology (which would have required several times the total energy generating capacity of the planet - which provides a nifty segue into "proving" that John Hutchison wasn't a charlatan.)

 

[Rory]

Either I'm confused or this is how this conversation is going:

1. In 2016 a couple of truthers questioned the size of the pile
2. The questions were answered and one poster disappeared and the other was banned
3. Then a few days ago @investigating911 posted detailed objective info about the size of the pile, I guess cos it was a place to share and store things he's learned along the way
4. Several others then said (to paraphrase) "what's the point of this discussion? it's dumb to question the size of the pile"
5. Investigating911 said (also to paraphrase) "it explains the so-called anomalies that some truthers think they've found"
6. Point 4 was repeated
7. I said "you're arguing with ghosts who haven't been here in 5 years"
8. Point 4 was repeated again

Probably I'm confused. Is i911 a truther? Is someone arguing that there was something "unusual about the debris pile"? There must be some explanation for the nature of the responses - responses that don't seem to directed at anyone or any point in particular.

 

[investigating911]

What does the debris pile being too shallow indicate that you are trying to find answers as to why?

It's confusing to me why the debris pile southwest of the footprint of the south tower if the debris generated by the south tower collapse was said to have mostly fell in a symmetrical manner. However @Marc Powell's explanation makes it more clear.

A large section of exterior column panels from the south side of the South Tower peeled away toward the southwest. It fell diagonally across the northbound lanes of West Street narrowly missing the building at 90 West Street and the Liberty Street Pedestrian Bridge, while squashing the Saint Nicholas Greek Orthodox Church. It can be seen through the smoke and dust in this picture taken shortly after the collapse:

Because clearing roadways was a priority in the days immediately after 9/11, few pictures exist showing debris in this area. Perhaps this information will put to rest the idea that the distribution of debris around the South Tower was not concentric about the tower footprint and that the depth of debris to the southwest was "too shallow."


Edit: Replaced photo with enhanced version having higher contrast.

Okay that explains it better. I think a common point of confusion is that even in very recent pictures after 9/11 (such as pictures taken on September 12, 2001 and September 13, 2001), a lot of the debris from West Street and Liberty Street has already been removed, leading some people to believe that there wasn't as much debris as there actually was after the collapse. The picture I posted was taken the night of September 12, 2001 and presumably a lot of debris on West Street and Liberty Street had already been cleaned up by then.

May I ask where you got the photo from? I can't find a lot of high resolution aerial pictures of the ensuing debris pile taken immediately after 9/11. Most of the pictures I have seen just show smoke obscuring most of the debris on the ground.

3. Then a few days ago @investigating911 posted detailed objective info about the size of the pile, I guess cos it was a place to share and store things he's learned along the way

Yes

4. Several others then said (to paraphrase) "what's the point of this discussion? it's dumb to question the size of the pile"
5. Investigating911 said (also to paraphrase) "it explains the so-called anomalies that some truthers think they've found"
6. Point 4 was repeated
7. I said "you're arguing with ghosts who haven't been here in 5 years"
8. Point 4 was repeated again

Probably I'm confused. Is i911 a truther? Is someone arguing that there was something "unusual about the debris pile"? There must be some explanation for the nature of the responses - responses that don't seem to directed at anyone or any point in particular.

No I'm not a truther, I just don't understand some things that have been seen in the visual pictures and am trying to understand why the visual evidence is not lining up what is reported. I'm not suggesting that what is reported is wrong, I'm just trying to figure out possible reasons why the visual evidence doesn't seem to match. In this case it ended up being because the visual evidence was after a significant amount of debris had already been cleared from West Street and Liberty Street, even just a day after 9/11.

 

[Jeffrey Orling]

.......

No I'm not a truther, I just don't understand some things that have been seen in the visual pictures and am trying to understand why the visual evidence is not lining up what is reported. I'm not suggesting that what is reported is wrong, I'm just trying to figure out possible reasons why the visual evidence doesn't seem to match. In this case it ended up being because the visual evidence was after a significant amount of debris had already been cleared from West Street and Liberty Street, even just a day after 9/11.

Are you referring to the media reports in the days of and following the event?
If so reporters are no more sophisticated in their understanding of science and physics than the general public is. I would put and stock in their "observations" (uniformed).
Shortly after the event "experts" began to weigh in and did so with very limited visual data. This lead to "theoretical" explanations / models such as the "pancake" collapse... or the Bazant calcs.
As visual evidence was assembled more reliable explanations emerged which were still based on limited "data". The public was demanding to know how a high rise building could simply collapse. Fires alone seemed intrinsically a stretch. The planes impacts did not immediately destroy the towers and so there was a "process" which led to their collapse which needed to be explained. That took NIST several years and independent researchers even longer. Unfortunately there has never been 100% consensus concerning the mechanisms / processes etc. that explain the collapse of the 3 buildings. And there likely never will be due to the absence of "numbers"... data from inside the buildings up until they came down. All explanations use reasonable assumptions. Further... the process was organic and chaotic and much like a black box... we may never know what was going on inside but we do know the result. And there may be multiple paths to that result. And this is precisely what has fueled discussions and debated for 2 decades.
CD has been ruled out because no evidence of CD exists. But this hasn't prevented truthers from continuing to advocate it was an inside job / CD because they believe this was the only way those buildings could come down.
All the visuals have been amply explained.

 

[Marc Powell]

It's confusing to me why the debris pile southwest of the footprint of the south tower if the debris generated by the south tower collapse was said to have mostly fell in a symmetrical manner. However @Marc Powell's explanation makes it more clear.

Okay that explains it better. I think a common point of confusion is that even in very recent pictures after 9/11 (such as pictures taken on September 12, 2001 and September 13, 2001), a lot of the debris from West Street and Liberty Street has already been removed, leading some people to believe that there wasn't as much debris as there actually was after the collapse. The picture I posted was taken the night of September 12, 2001 and presumably a lot of debris on West Street and Liberty Street had already been cleaned up by then.

May I ask where you got the photo from? I can't find a lot of high resolution aerial pictures of the ensuing debris pile taken immediately after 9/11. Most of the pictures I have seen just show smoke obscuring most of the debris on the ground.


Yes

No I'm not a truther, I just don't understand some things that have been seen in the visual pictures and am trying to understand why the visual evidence is not lining up what is reported. I'm not suggesting that what is reported is wrong, I'm just trying to figure out possible reasons why the visual evidence doesn't seem to match. In this case it ended up being because the visual evidence was after a significant amount of debris had already been cleared from West Street and Liberty Street, even just a day after 9/11.

The photo I posted was from Release 08 of the 2011 NIST Freedom of Information Act release. The photos from Release 08 can be found in the NIST 911 Vault at https://archive.org/details/nist-911. Here is another photo from the NYPD "Police Overheads" folder in the FOIA release that shows the distribution of debris southwest of the South Tower as West Street was being cleared on the morning of September 12. Debris is much deeper than "shin-deep," wouldn't you agree?



By the way, the AE911Truth web site will never present photos showing the early removal of large sections of intact structure that had peeled away from the WTC towers. Richard Gage takes advantage of the scarcity of such photos to support his lies about the buildings being reduced to individual structural components by explosives.

 

[Marc Powell]

Are you referring to the media reports in the days of and following the event?
If so reporters are no more sophisticated in their understanding of science and physics than the general public is. I would put and stock in their "observations" (uniformed).
Shortly after the event "experts" began to weigh in and did so with very limited visual data. This lead to "theoretical" explanations / models such as the "pancake" collapse... or the Bazant calcs.
As visual evidence was assembled more reliable explanations emerged which were still based on limited "data". The public was demanding to know how a high rise building could simply collapse. Fires alone seemed intrinsically a stretch. The planes impacts did not immediately destroy the towers and so there was a "process" which led to their collapse which needed to be explained. That took NIST several years and independent researchers even longer. Unfortunately there has never been 100% consensus concerning the mechanisms / processes etc. that explain the collapse of the 3 buildings. And there likely never will be due to the absence of "numbers"... data from inside the buildings up until they came down. All explanations use reasonable assumptions. Further... the process was organic and chaotic and much like a black box... we may never know what was going on inside but we do know the result. And there may be multiple paths to that result. And this is precisely what has fueled discussions and debated for 2 decades.
CD has been ruled out because no evidence of CD exists. But this hasn't prevented truthers from continuing to advocate it was an inside job / CD because they believe this was the only way those buildings could come down.
All the visuals have been amply explained.

I agree with everything you are saying but need clarification on one issue. For years, I have been saying that the progressive failure of floor supports in the Twin Towers resulted in the floors "pancaking" into the basement at an overall acceleration of approximately 2/3 G. Wouldn't pancaking of floors be an appropriate description for what happened, synonymous with the "ROOSD" mechanism I frequently see reference to hereabouts?

 

[Jeffrey Orling]

I agree with everything you are saying but need clarification on one issue. For years, I have been saying that the progressive failure of floor supports in the Twin Towers resulted in the floors "pancaking" into the basement at an overall acceleration of approximately 2/3 G. Wouldn't pancaking of floors be an appropriate description for what happened, synonymous with the "ROOSD" mechanism I frequently see reference to hereabouts?

My sense is that the floor destruction was not uniform over the entire footprint. Close and compete but not like dropping dics on a phonogragh. Think of the "front" as you would an avalanche.

 

[econ41]

For years, I have been saying that the progressive failure of floor supports in the Twin Towers resulted in the floors "pancaking" into the basement at an overall acceleration of approximately 2/3 G.

That is correct.

Wouldn't pancaking of floors be an appropriate description for what happened, ...

Also correct but the term "pancaking" has been the cause of confusion, ambiguity and deliberate mendacity. The FEMA preliminary report which pre-dated the NIST investigation suggested that "pancaking" was what initiated the collapses of Twin Towers. Be clear as to the two main stages of collapse viz: "initiation" and "progression". FEMA suggested initiation was by pancaking. It wasn't. NST rejected pancaking as the initiation mechanism. And did not explain the "progression" stage other than as "global collapse was inevitable". So, for years, truthers played games with the related confusions.

Bottom Lines: (a) Yes "progression" - the stage you refer to can correctly be described as "pancaking"; and (b) I and some other debunkers deliberately do not use the term simply to avoid the mendacity and potential confusion. "ROOSD" is easier and more specific to WTC collapses.

Wouldn't pancaking of floors be an appropriate description for what happened, synonymous with the "ROOSD" mechanism I frequently see reference to hereabouts?

Yes - but be wary of the confusions already described. And "pancaking" is a generic term whilst ROOSD is specific to and descriptive of the unique features of the WTC Twin Towers collapses. "ROOSD" is itself subject of contention because the acronym was put forward by a couple of truther side researchers who correctly identified the real mechanism of progression at a time when most debunkers were presenting wrong explanations. And several years of polarised "debate" ensued. The debunker side mental gymnastics were amusing to follow.

 

[econ41]

My sense is that the floor destruction was not uniform over the entire footprint. Close and compete but not like dropping dics on a phonogragh. Think of the "front" as you would an avalanche.

Whilst you are probably correct the factor had no detectable pragmatic effect. Gross overload sheared all floors in succession. Milli or even micro-second differences in impact timing were of no consequence.

 

[Marc Powell]

That is correct.

Also correct but the term "pancaking" has been the cause of confusion, ambiguity and deliberate mendacity. The FEMA preliminary report which pre-dated the NIST investigation suggested that "pancaking" was what initiated the collapses of Twin Towers. Be clear as to the two main stages of collapse viz: "initiation" and "progression". FEMA suggested initiation was by pancaking. It wasn't. NST rejected pancaking as the initiation mechanism. And did not explain the "progression" stage other than as "global collapse was inevitable". So, for years, truthers played games with the related confusions.

Bottom Lines: (a) Yes "progression" - the stage you refer to can correctly be described as "pancaking"; and (b) I and some other debunkers deliberately do not use the term simply to avoid the mendacity and potential confusion. "ROOSD" is easier and more specific to WTC collapses.

Yes - but be wary of the confusions already described. And "pancaking" is a generic term whilst ROOSD is specific to and descriptive of the unique features of the WTC Twin Towers collapses. "ROOSD" is itself subject of contention because the acronym was put forward by a couple of truther side researchers who correctly identified the real mechanism of progression at a time when most debunkers were presenting wrong explanations. And several years of polarised "debate" ensued. The debunker side mental gymnastics were amusing to follow.

Your reference to the FEMA preliminary report helps to provide context for statements subsequently made by NIST that have been a continual source of grist for truther mills. On the NIST Towers Investigation FAQ webpage, (https://www.nist.gov/world-trade-center-investigation/study-faqs/wtc-towers-investigation), their answer to FAQ No. 28, includes the following paragraph:

NIST's findings do not support the "pancake theory" of collapse, which is premised on a progressive failure of the floor systems in the WTC towers (the composite floor system—that connected the core columns and the perimeter columns—consisted of a grid of steel "trusses" integrated with a concrete slab; see diagram). Instead, the NIST investigation showed conclusively that the failure of the inwardly bowed perimeter columns initiated collapse and that the occurrence of this inward bowing required the sagging floors to remain connected to the columns and pull the columns inwards. Thus, the floors did not fail progressively to cause a pancaking phenomenon.

Of course, when the entire answer to FAQ 28 is read, it becomes obvious that NIST was only referring to conditions that initiated the collapse. The parenthetical phrase “pancake theory” was most likely a reference to incorrect FEMA conclusions. However, that doesn’t stop truthers like David Chandler from misrepresenting what NIST said and claiming that they rejected pancaking of floors as the primary mechanism for global collapse.

 

[econ41]

Your reference to the FEMA preliminary report helps to provide context for statements subsequently made by NIST that have been a continual source of grist for truther mills.

Exactly.

Of course, when the entire answer to FAQ 28 is read, it becomes obvious that NIST was only referring to conditions that initiated the collapse. The parenthetical phrase “pancake theory” was most likely a reference to incorrect FEMA conclusions.

And we are discussing issues that were - or should have been - resolved 10-12 years ago. But the confusions continue. Part of the reason I am usually pedantic to define what specific stage of collapse my explanations refer to. And I identify a total of four. Not just "initiation" and "progression".

So I would probably have said "...was most likely a reference to incorrect FEMA conclusions about the mechanism of collapse initiation" to eliminate any ambiguity.

However, that doesn’t stop truthers like David Chandler from misrepresenting what NIST said and claiming that they rejected pancaking of floors as the primary mechanism for global collapse.

Yes. Whether he is a slow learner and still ignorant OR a deliberate "liar by half truth, ambiguity, conflation and innuendo".

 

[Mendel]

My sense is that the floor destruction was not uniform over the entire footprint. Close and compete but not like dropping discs on a phonograph. Think of the "front" as you would an avalanche.

For the "younger" readership, an illustration:
Source: https://m.youtube.com/watch?v=8QK_dgAV5yA

 

[Marc Powell]

Exactly.

And we are discussing issues that were - or should have been - resolved 10-12 years ago. But the confusions continue. Part of the reason I am usually pedantic to define what specific stage of collapse my explanations refer to. And I identify a total of four. Not just "initiation" and "progression".

So I would probably have said "...was most likely a reference to incorrect FEMA conclusions about the mechanism of collapse initiation" to eliminate any ambiguity.


Yes. Whether he is a slow learner and still ignorant OR a deliberate "liar by half truth, ambiguity, conflation and innuendo".

David Chandler is definitely operating under the third option... he is a deliberate "liar by half truth, ambiguity, conflation and innuendo." In his paper Destruction of the World Trade Center North Tower and Fundamental Physics (available at http://www.journalof911studies.com/volume/2010/ChandlerDownwardAccelerationOfWTC1.pdf ), Chandler presents a strawman version of the NIST collapse theory while misquoting and rewording the NIST response to (what is currently) FAQ 28 so as to eliminate reference to collapse initiation. In so doing, Chandler gives his readers the false impression that NIST had rejected pancaking of floors as a mechanism that sustained the collapse after it had begun.

 

[econ41]

@Marc Powell. Probably too far off topic here BUT the situation we are discussing is an amusing collection of ironies. The main theme "both sides were right for the wrong reasons". Take this portion of the paper you linked:

Bazănt describes a scenario in which the top assembly of the building remains rigid as it crushes the lower sections of the building into rubble. Only when the lower section has been crushed into a compact debris pile does the top assembly crush itself. This proposed process has become known as "Crush-Down" followed by "Crush-Up."* His claim is that once collapse is initiated, it becomes inevitable.** Using Bazănt's analysis as a rationale, the NIST report limits its own investigation to the events leading up to the "initiation" of collapse, claiming that everything thereafter was inevitable and required no further investigation.*** NIST thereby sidesteps any consideration of what actually happened during the collapse itself, including evidence that might bring the correctness of Bazănt's analysis into doubt.****

Content from External Source

* Which hypothesis ("Crush Down/Crush Up") is wrong for the WTC Twin Towers collapses BUT AFAIK few if any debunkers have the courage or physics comprehension to admit "Bazant was wrong".

** Which is true but overlaid by about five layers of irony - NIST was probably right for the wrong reasons. Because neither Bazant's logic nor NIST's if they relied on Bazant are correct in reasoning. And one of the ironies it was valid claims first raised by truther researchers which proved NIST's claim correct. AND based on valid argument.

*** Correct despite "right for wrong reasons" and very few debunkers either get the rationale or the irony.

**** And again Chandler is correct. And so few debunkers comprehend the reasoning or are prepared to admit when a truther is right;.

 

[econ41]

For the "younger" readership, an illustration:
Source: https://m.youtube.com/watch?v=8QK_dgAV5yA

We three risk giving away our age.

On the point that @Jeffrey Orling raises and I commented on the better analogy would be if the 12" 33RPM vinyl was broken into segments which fell independently but "near enough" concurrently. Reality was not "flat disk aka flat floor" FALLING onto anothr "flat" disk or floor. But that detail has no pragmatic effect on understanding the mechanism.

 

[Mendel]

Well, pancakes aren't exactly rigid, either.

 

[Jeffrey Orling]

I suspect because of friction... after a few seconds the "collapse front" was uniform over the foot print inside the "cage" of the perimeter columns. As such it would impact an entire floor almost simultaneously breaking it into segments/pieces/grains... pick your term... which became the "face" or the collapse front of the mass of floors from above.

Imagine filling up a floor with water until it failed... and as the water would spread throughout the footprint.. the floor would be experiencing a uniform increase in load... until the load exceed capacity and the floor would fail breaking apart and free from the columns that supported it.