What's the best popular account of the WTC collapses?

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Maybe "authority" was a poor choice of words. I was trying to say that you and @Jeffrey Orling consider yourself competent analysts of the collapses, i.e., you are qualified to understand them, and you probably don't consider yourselves uniquely qualified. Who do you recognize as peers and how do you recognize them? Clearly, it's not just by whether they agree with you. After all, you recognize each other.

And I should have focused on this question: Is there someone who, if they wrote "the book" on it, or if someone else wrote "the book" about them, you'd eagerly buy and read it? It's sort of like this: there are lots of "popular physics" books, but many people were especially excited when Leon Lederman published The God Particle and eagerly anticipated the follow-up after the Higgs discovery. That's in part because Lederman was a recognized authority and in part because he's an interesting person. Is there anyone like that in re the WTC collapses?
I have already mentioned two authors who write very readable and I think successful books on topics of science for "every-man"... Dawkins and McPhee. Neither of them is an engineer who did any research on building collapses or the WTC event.

The engineer whose I think might write a credible book might be Guy Nordenson...

https://en.wikipedia.org/wiki/Guy_Nordenson

After graduating from UC Berkeley he worked at Forell/Elsesser Engineers in San Francisco (1978-1982) and Weidlinger Associates in New York City (1982–1987), before establishing the New York office of Ove Arup & Partners in 1987 where he was a director until leaving in 1997 to begin his own structural engineering practice, Guy Nordenson and Associates.[1]

Nordenson is also a professor at the Princeton University School of Architecture and is a Faculty Associate at the Andlinger Center for Energy and the Environment, the University Center for Human Values, the Princeton Environmental Institute, and the Department of Civil and Environmental Engineering.[2]

Selected publications[edit]​

  • Structures of Coastal Resilience, with Catherine Seavitt Nordenson and Julia Chapman, Island Press, Washington DC, 2018[31]
  • Reading Structures: 39 Projects and Built Works, Lars Müller Publishers, Zurich, 2016[32]
  • Patterns and Structure: Selected Writings 1972–2008, Lars Müller Publishers, Baden, 2010[33]
  • On the Water | Palisade Bay, with Catherine Seavitt and Adam Yarinsky, Hatje Cantz Verlag/MoMA Publications, Berlin, 2010[34]
  • Seven Structural Engineers – The Felix Candela Lectures in Structural Engineering, editor, MoMA Publications, New York NY, 2008[35]
  • Tall Buildings, editor with Terrance Riley, MoMA Publications, New York NY, 2003[36]
  • WTC Emergency – Damage Assessment of Buildings Structural Engineers Association of NY Inspection of September and October 2001, Volume A Summary Report, and B-F on DVD, SEAoNY, New York NY, 2003[37]"
 
I think it would be very strange if there were no popular books (and only government reports) about bears. And that would allow people to believe much stranger things.
You are implying that there are no popular books and only government reports on 9/11.
https://en.wikipedia.org/wiki/List_of_books_about_the_September_11_attacks
Books on 911.png

the book I'm imagining would help many truthers in the "set", even if it would help few truthers in the "subset".
The problem with bigfoot isn't that there are books about bears; it's that there are books about bigfoot. If you want to talk to the people believing in bigfoot, write about bigfoot.

I came to Metabunk from the Flat Earth scene. The amount of books written on what these guys doubt is staggering, and so is the amount of people with training and experience that have first-hand counterevidence.
Flat Earthers still exist. My impression is that those who are known to have reverted from that did so because of people addressing those beliefs specifically.

In your opinion, do existing popular accounts of the collapse have an effect (e.g. the wikipedia page)?

But let's put some substance into this discussion.
Imagine the perfect book on 9/11 that you're looking for exists. Open this imagined book to the table of contents. What do you see? Please be specific.
 
You are implying that there are no popular books and only government reports on 9/11.
https://en.wikipedia.org/wiki/List_of_books_about_the_September_11_attacks
Books on 911.png


The problem with bigfoot isn't that there are books about bears; it's that there are books about bigfoot. If you want to talk to the people believing in bigfoot, write about bigfoot.

I came to Metabunk from the Flat Earth scene. The amount of books written on what these guys doubt is staggering, and so is the amount of people with training and experience that have first-hand counterevidence.
Flat Earthers still exist. My impression is that those who are known to have reverted from that did so because of people addressing those beliefs specifically.

In your opinion, do existing popular accounts of the collapse have an effect (e.g. the wikipedia page)?

But let's put some substance into this discussion.
Imagine the perfect book on 9/11 that you're looking for exists. Open this imagined book to the table of contents. What do you see? Please be specific.
Almost all of the citations I looked at are fiction, political discussions, pro and anti conspiracy stuff... and I didn't hit on any "technical discussions" about the collapse of the towers... Help me out.
 
The engineer whose I think might write a credible book might be Guy Nordenson...
I think we have found a winner! Thanks, Jeffrey. I'm now watching his lecture on "Patterns and Structure" (a presentation of the book of the same name). He begins by invoking Ezra Pound's "Vortex". Awesome.

Update: just got to the WTC! [Update2: definitely the sense that here's a man who knows what he's talking about. He doesn't talk about collapse, but he knows exactly how strong these buildings were and, if you will, how these buildings were strong.]

His collaboration with CS Nordensen (wife? daughter?) and Julia Chapman also looks well done. I've just had a quick look, but it opens with some mention of hurricanes -- so there is the hook into disasters. Interesting.

Yes, if I were an editor pitching this idea to my publisher, I'd probably propose trying to get Nordensen to author or co-author it.
 
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@Mendel wrote:
"But let's put some substance into this discussion.
Imagine the perfect book on 9/11 that you're looking for exists. Open this imagined book to the table of contents. What do you see? Please be specific."

1. Summary of the evolution of tall buildings - skyscrapers
3. Primer of the engineering for multi-story structures
4. Innovations of design of high rise buildings - survey
5. Development of the WTC project
6. Features of the design and construction of the 3 towers at the WTC
7. Why structures stand and how do they fall?
8. What we know and what we don't know about what happened on 9/11 to the three towers
9. Discussion of failures in complex systems
10. What were the lessons learned from the three collapses on 9/11
10. Epilogue - How we live in a technically complex world
 
If you want to talk to the people believing in bigfoot, write about bigfoot.

I came to Metabunk from the Flat Earth scene.
Another non-scientific intuition of mine: belief in CD is much more widespread and much more intellectually robust than belief in Bigfoot and Flat Earth. And, not incidentally (for the purpose of this discussion): there are tons of popular books on bears and the (round) Earth. That is, it's possible to take a detailed, amateur interest in the fauna of the Rockies and the shape of the Earth without involving oneself in conspiracy theories or pseudoscience of any kind. But if you want to know how the WTC collapsed, you've got to engage with people in forums like this. I think that's interesting and problematic. And something should/could be done about that.
 
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@Mendel wrote:
"But let's put some substance into this discussion.
Imagine the perfect book on 9/11 that you're looking for exists. Open this imagined book to the table of contents. What do you see? Please be specific."

1. Summary of the evolution of tall buildings - skyscrapers
3. Primer of the engineering for multi-story structures
4. Innovations of design of high rise buildings - survey
5. Development of the WTC project
6. Features of the design and construction of the 3 towers at the WTC
7. Why structures stand and how do they fall?
8. What we know and what we don't know about what happened on 9/11 to the three towers
9. Discussion of failures in complex systems
10. What were the lessons learned from the three collapses on 9/11
10. Epilogue - How we live in a technically complex world
Yes, this looks pretty good to me. I would include a prologue about how the FEMA and NIST investigations were organized and related to "codes" and "standards" (why the disclaimers, etc.) And this would tie back into the epilogue Jeffrey suggests. It would also allow for a running "narrative" about the engineers who designed the buildings and investigated the collapses. "Human interest" stuff. But not separate chapters, just "local color" throughout each chapter. Michael Lewis (Moneyball, Big Short) is good at that sort of thing.
 
9/11 conspiracists are often caught in some contradictory thinking.

Can buildings collapse for ANY reason aside from intentional demolition?

We know that they DO from earthquakes...

We know that heat can critically weaken and often destroy structural capacity of building materials

Was it possible that conditions inside the WTC buildings met the criteria for loss of capacity of the materials of the structural system?

Conspiracy theorists must assert that conditions were not met... and they do this without proof and then conclude the force/energy was supplied by placed devices.
 
Was it possible that conditions inside the WTC buildings met the criteria for loss of capacity of the materials of the structural system?
One way to meet the truthers halfway (although I'm not suggesting the book we're talking about do this explicitly) is to imagine no planes hitting the building that day. What is the minimum amount of structural weakening (by any means) that would need to be carried out across about five floors in the space of two hours to bring a tower down?

Imagine a crew of unlimited size and resources using cutter charges and blow torches (and hacksaws and bolt cutters and sledge hammers, if you want), working with no regard for their own safety, to take out columns and floor connections in some sequence. At what point does the whole building come down as it did on 9/11?

That would give us a great indication/visualization of the damage that the planes/fires were able to do, and in language that the truthers can understand. I'm not actually suggesting that's what happened, of course, but it would identify a possible sequence of structural effects, many of which are of course already presented in the NIST report using less evocative imagery.
 
One way to meet the truthers halfway (although I'm not suggesting the book we're talking about do this explicitly) is to imagine no planes hitting the building that day. What is the minimum amount of structural weakening (by any means) that would need to be carried out across about five floors in the space of two hours to bring a tower down?

Imagine a crew of unlimited size and resources using cutter charges and blow torches (and hacksaws and bolt cutters and sledge hammers, if you want), working with no regard for their own safety, to take out columns and floor connections in some sequence. At what point does the whole building come down as it did on 9/11?

That would give us a great indication/visualization of the damage that the planes/fires were able to do, and in language that the truthers can understand. I'm not actually suggesting that's what happened, of course, but it would identify a possible sequence of structural effects, many of which are of course already presented in the NIST report using less evocative imagery.
Interesting thought experiment!

There is the problem of setting up the conditions and then getting out of the building before it comes down... you know how demo crews do it... they set charges etc. use det cord and then "pull the trigger" remotely.

For 1wtc I would imagine setting charges or some type to destroy probably 50% of the truss seats. or the top flange of the truss on perhaps 4 or 5 floors... set these charges off simultaneously from a remote location and set of a ROOSD. It's not clear that a tower missive all the OSS would collapse. Or would be stand with an intact core and a 40'-50' high pile of debris filling the lower section of the tower? Would the debris bust through the glass at the plaza level?

But in this collapse there is not separation of the top block.

And it's not clear that a hollow facade and the intact core would collapse.

To collapse the core a progressive floor collapse would have to be "rigged" inside the core... and the collapse would strip the core of all bracing. Unbraced core and facade would probably too unstable and collapse. Mission accomplished. But the collapse form would not mimic what happened on 9/11.

2wtc is a bit more tricky as they would have to make the top section tip as it fell. Would placed cutter charges cutting the axial structure on the SE accomplish the toppling and tllting of the top? Yes it could. Seems very tricky bit conceivable.

7wtc might be the simplest to pull off... Set up devices to burn/cut the seat of the girder on col, 79 on several consecutive floors... causing the local floor collapse, making the column buckle causing collapse of the NE up to the roof and down to the foundation and then transfers would lead to destruction to progress westward and finally the moment frame would lose all axial support and come down.

Looks like a time consuming and complex demolition.... for the twins and a more manageable one for 7wtc. But all three would require remote control unless the demo installers were to be sacrificed.

Forget over time pay.

If the miracle crew were to use col 79 scenario they would have to "remove the girder seat" and get the hell out pretty damn quick as the floor(s) above would crush them
 
There is the problem of setting up the conditions and then getting out of the building before it comes down.
I hoped to take this out of the equation by stipulating that the crew would have "no regard for its own safety". I guess we could think of it as a "suicide mission", but one involving hundreds (thousands?) of terrorists. If you assign one person to each column/connection, and assume everyone does their job, I don't see why you wouldn't be able to bring about exactly the same results as what happened on 9/11 in an hour or two. [Update: I could be wrong about this, but then we'd just need to give the crew some extra capabilities. After all, it was possible to catastrophically undermine the structure within two hours.]

In theory, of course. Only in theory. The value of this description would be walking the reader through the gradual weakening of the structure, one failure point at a time. Some of the weakening would happen instantly at the start, some would start later and take a few minutes (maybe even an hour) as the operator cuts through a beam, some of it would happen instantly at the end when a charge is detonated. But in all cases we get the explicit weakening and finally failure of a discrete structural element. So there's no mystery. Of course, all this damage would also need to be plausibly caused by impact + fire in under two hours.
 
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....
The value of this description would be walking the reader through the gradual weakening of the structure, one failure point at a time. Some of the weakening would happen instantly at the start, some would start later and take a few minutes (maybe even an hour) as the operator cuts through a beam, some of it would happen instantly at the end when a charge is detonated. ....
Gradual weakening is probably the wrong way to approach this thought experiment.

What happens, I think, was that the system as a composite is static and then goes through an instant "phase shift" to dynamic and collapsing.

So if you try to mimic the runaway floor slab collapse you need to not gradually fail one connection at a time... but get enough connection to fail at once to initiate the runaway collapse. So you would to engineer how many "seat connections" had to fail to release an entire floor slab. I don't recall the exact number of floor truss seats. But each seat supported 2 trusses and of course they had support at the facade and at the core belt girder. There would be over 150 I would guess. How many would have to be removed for the entire slab to drop as a plate... 1/4, 1/2, 3/4? and this would have to be done on perhaps 3 floors at the same time.

I have no idea how long it would take to "wire" the det cord and place the explosives and 200 or 300 seats.

Destroying the core using a multiple floor slab drop would involve destroy larger, more robust but few lateral beam splices or knife connections. Add another tens of connections to wire up the det cord.

The set them off at once and multiple floors would collapse and go runaway to the ground leaving behind only intact core columns and exterior tube of panels. That may collapse in short order unable to resist even normal wind loads and Euler forces.

This would be impossible to do unnoticed.
 
This would be impossible to do unnoticed.
Yes, leave that to the conspiracy theorist to imagine. The point is that you'd be describing an "operation" on the building that does nothing more than what the impacts and fires in fact did.

As ever, I would also want the same operation to be modelled on a simpler structure so it would be easier to keep track of the process. I.e., fewer columns and connections to break or weaken but with the same catastrophic effect.
 
Yes, leave that to the conspiracy theorist to imagine. The point is that you'd be describing an "operation" on the building that does nothing more than what the impacts and fires in fact did.

As ever, I would also want the same operation to be modelled on a simpler structure so it would be easier to keep track of the process. I.e., fewer columns and connections to break or weaken but with the same catastrophic effect.
I would argue (as I have above) that in the twins towers the collapse was not actually accomplished by destroying the truss seats. The truss seats "failed" because the mass of floor material caused the floor slabs to be over loaded and they were destroyed as a CONSEQUENCE of the collapsing mass. The collapsing mass was freed by expanding.... ie lateral movement of core bracing pushing column ends out of alignment leading the buckling failure and collapse of the slabs being supported.
 
I am proposing what would be, analogically, a good book about (or at least including) the bears that do exist in the same environment. That book would not, of course, even mention Bigfoot.

I'm aware of that.

Belief in Bigfoot is constrained by a continuously updated set of books that satisfy general, popular curiosity about mountain fauna. These books are informed by continuously updated zoological research -- ongoing scientific study of the habitat of, say, the Rockies.
You repeating yourself is not going to change my mind.

Over 20% of Americans believe in Bigfoot. I've seen opinion polls (Americans) that peg CD demolition at up to 16% if you add "likely" and "very likely".
note: I don't mind if someone wants to exert that much effort to write your book. I just don't think it will help much to save conspiracy believers, you'd have a lot more success with a video and a huge marketing budget.
 
I'm aware of that.


You repeating yourself is not going to change my mind.

Over 20% of Americans believe in Bigfoot. I've seen opinion polls (Americans) that peg CD demolition at up to 16% if you add "likely" and "very likely".
note: I don't mind if someone wants to exert that much effort to write your book. I just don't think it will help much to save conspiracy believers, you'd have a lot more success with a video and a huge marketing budget.
Really... who cares about 9/11 conspiracy nut jobs???? It's like who cares about Scientologists nut jobs? Family members and friends feel they have lost someone... and in a sense they have.

Not much you can do about dumb.... and willful dumb...

If anyone wants to learn these days google and YouTube can get them out of their dumb fog.

@Thomas B's book would sort of fill a gap... providing a "popular" book that does not require or target trained engineers and scientists. A YouTube or series of them might reach more people in this day and age. Popular level teaching takes place at planetariums, aquariums and natural history museums and there's plenty of demand for them.
 
For the Twin towers neither "shifted half-a-column off" or "dropped half-a-floor onto" were parts of the actual mechanisms.

The collapsing mass was freed by expanding.... ie lateral movement of core bracing pushing column ends out of alignment leading the buckling failure and collapse of the slabs being supported.

It'd be interesting to know if the two of you are agreeing or disagreeing here. I.e., do you have the same ideas about what freed the energy to destroy the towers?
 
It'd be interesting to know if the two of you are agreeing or disagreeing here. I.e., do you have the same ideas about what freed the energy to destroy the towers?
My conception of the initiation is not "seen" much online or in print. What are its attributes? Something like this:

1. it was a progressive process driven by heat causing bracing to expand
2. the expanded bracing only had to move a column enough to reduce the bearing area of the upper column on the lower column. Inadequate bearing area would lead to web and/or flange buckling. And that would render the load path non performing.
3. The bracing was only able to displace a column if the column was "unrestained" laterally. This would be the case where there were plane destroyed columns and bracing. And the intact bracing surrounding them would be unrestrained toward the location of the plane destroyed columns.
4. Buckled columns would see their axial loads "transferred" laterally to adjacent/surrounding columns. This would reduce the "reserve capacity" of intact columns surrounding the area of missing columns.
5. Steps 3, 4 & 5 would repeat causing the area of no functioning columns to expand "outward" leaving fewer columns carrying increased loads with less reserved capacity until the "hole" of no supporting/functioning columns reached the center of the core under the antenna.
6. When the center of the core columns could no longer support axial loads and began to buckle, the antenna began to drop into the roof destroying the hat truss and transferring dynamic lateral loads to the facade.
7. As the columns were failing... the floor areas supported by those columns was dropping on to intact floors.
8. With the antenna drop all the floor areas under it dropped onto the intact floors of the top of the lower section.
9. The bucking and destruction of the central core... in the upper section above the plane strike zone... pulled the 24 perimeter core columns inward as the cores center was collapsing.
10. The 14 perimeter core columns dropping or falling into the core cause the core side of the perimeter floor systems to lose core side support and that caused all the floors outside the core of the top block to "tip and slip/fall" toward the center of the core.
11. the interior floor systems collapse became the mass that drove the runaway collapse of the floors of the intact lower block referred to as ROOSD.

ROOSD of the lower block requires a threshold mass to drive it. That would be the interior of the upper block. It could also be a crush up - crush down if the upper block descended as an intact block. For that to happen there would have to be simultaneous buckling "symmetrically" of enough columns to reduce capacity below the "service" load of the entire to block. This might be possible if the entire block was displaced a small amount reducing bearing area. This would be complicated by the staggered arrangement of the facade column panels. I think the perhaps the cage of the upper blocks might have held together as their insides broke apart and spilled onto the intact tower floors below.

Whatever the "sequence" or the progression of interior failures.... they would have to support the observations from outside. So this is truly a black box phenomena with few clues of / to the workings going on inside the black box.
 
My conception of the initiation is not "seen" much online or in print. What are its attributes? Something like this...
I want to hold you to the fire a little here. I hope that's okay. I'm not asking you what your view is but whether you think @econ41 agrees with you. The reason I'm putting it that way is that we all know how to detect "wrong" accounts (i.e., those that involve or imply controlled demolition). That means that we don't just speak for ourselves, but can also (correctly) interpret the (wrong) views of others. So, in this case, I was asking how each of you reads "the other guy's" statement -- obviously, in the context of your familiarity with each other.
 
I want to hold you to the fire a little here. I hope that's okay. I'm not asking you what your view is but whether you think @econ41 agrees with you. The reason I'm putting it that way is that we all know how to detect "wrong" accounts (i.e., those that involve or imply controlled demolition). That means that we don't just speak for ourselves, but can also (correctly) interpret the (wrong) views of others. So, in this case, I was asking how each of you reads "the other guy's" statement -- obviously, in the context of your familiarity with each other.
Econ and I agree 100% I believe on the mechanisms of the collapse phase... ie once the top blocks are dropping and freed from the tower destroying the lower block.

There seems little consensus on the initiation.... what got the top blocks moving down (aside from gravity of course).
 
It'd be interesting to know if the two of you are agreeing or disagreeing here. I.e., do you have the same ideas about what freed the energy to destroy the towers?
Disagreeing strongly. We agree the main features of the "big picture". We disagree - have for many years disagreed - the details. The two main problems being the same ones which are now derailing this discussion.

I see two very distinct and separate goals viz:
1) Explain how the twowers could be caused to collapse by "CD" methods; OR
2) Explain "what really happened" i.e. the actual impact damage and fire induced collapses of 9/11.

Recent posts have been speculating about CD methods. I explored several options for that in previous years on other forums. Including a couple of collaborative ventures assisting genuine truthers to formulate hypotheses for CD induced collapses which would "look like" the real events.

I have also extensively explained the mechanisms of the real collapses for Twin Towers and often at the concept and language level needed by lay persons as per your target audience. My offers to do so for you have not been progressed.

I remain conscious of the expected posting standards of this forum where the current topic is about a book as the best popular account and NOT a detailed exposition of methods of collapse whether CD speculation or legitimate explantion of what actually happened.
 
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...the same ones which are now derailing this discussion.
"Derailing." "Moving the goal posts." All this concern about keeping things on track and within bounds! From my point of view, all 347 posts in this thread became worth it (for the nth time) when @Jeffrey Orling mentioned Guy Nordenson. Sure there's the odd detour, but the problem is becoming clearer to me as we go along. This is far from the train wreck that online discussion boards can be.
 
NIST didn't detail the "global collapse". They described initiation in the 3 bldgs. There is consensus in what the energy inputs were: fire and some mechanical damage. There is no consensus on what parts of these structures were impacted by the fire... and what it actually did....
Did it fatally weaken columns?
Did it fatally weaken floor trusses?
Did it fatally weaken rolled section bracing?
Was the lead failure of the twins the bar trusses?
Was the lead failure of the twins in the core?
Was col 79 the only one failed which caused the collapse of the EPH?
Was the failure of 7wtc a runway collapse of flooring around col 79
Why did the collapse of column 79 lead to the collapse of the entire building?
Were these designs especially vulnerable to global (runaway) collapse?
If they were vulnerable... why? Was this vulnerability overlooked in developing the design or was it considered too unlikely for runaway conditions to present?
 
Again.... a book cannot be written because there is no consensus on all aspects of the collapses. A book would / should include a survey of all reasonable theories of the "details" most of which are to be found online and not in formally published presentations.

Any structural engineer would be qualified to write the book, but engineer may not be a good "author" for popular non fiction as the two authors mentioned upthread.
 
This is far from the train wreck that online discussion boards can be.

It's a beyond a train wreck for the old standards of Metabunk. I think that is what econ is (understandably) having a hard time processing. Although eventually Mick might throw this thread into "Open Discussion" where it belongs.

The truth is if you want to imply or ask questions about a specific sub topic of 911, then you should do so in the appropriate thread dedicated to that specific topic. The reason for that is that gish gallop threads such as this one are no help to the outside reader who comes to MB for information. While your original topic was somewhat interesting, it was resolved on the first page. You just weren't listening. the rest of this thread is noise.
 
.... a book cannot be written because there is no consensus on all aspects of the collapses. A book would / should include a survey of all reasonable theories of the "details" most of which are to be found online and not in formally published presentations.
I find this somewhat unsatisfying, but I guess it may be true. It shouldn't be the case that (a) there's no consensus on the central questions (like initiation) and (b) that the theories being considered are "to be found online" rather than in formal publications, represented by recognized experts. I go back to my "mantra"; if this is the state of the science on the WTC, that's interesting ... and it should go in the book. Cheers.
 
It's a beyond a train wreck for the old standards of Metabunk. I think that is what econ is (understandably) having a hard time processing. Although eventually Mick might throw this thread into "Open Discussion" where it belongs.
Fully agreed. All three points. I respect the "on-topic" focus standards which are expected on Metabunk and a few other forums. Hence my multiple attempts to revert to the OP topic AND offers to fully discuss WTC Twin Towers collapse details in a more appropriate thread.

And my reluctance to respond to off topic details posted by some members.
While your original topic was somewhat interesting, it was resolved on the first page. You just weren't listening. the rest of this thread is noise.
True.
 
Fully agreed. All three points. I respect the "on-topic" focus standards which are expected on Metabunk and a few other forums. Hence my multiple attempts to revert to the OP topic AND offers to fully discuss WTC Twin Towers collapse details in a more appropriate thread.

And my reluctance to respond to off topic details posted by some members.

True.
agreed but whomever is moderating needs to moderate.... and move technical discussions to the appropriate thread.
 
ProffQuals.pngReally? What are your professional qualifications?
Formal quals in Civil and Military Engineering, Training, Law. The most relevant expertise arising from (a) breadth of technical experience (b) practice at explaining complex technical issues to lay person audiences of the type Thomas B has in mind AND (c) I've already written many chapters of the book in on-line discusions. EITHER targetted at lay persons or at about undergraduate level which would need "translation down".

I'm not a professional writer and I would need a good editor watching over my shoulder.

Bottom line #1 - I would always prefer face to face - either one-on-one or small group rather than a "Book" which would need to predict questions and topic scope.
Bottom line #2 - I doubt there is a market. I've been offering to explain details for many years and only about 4 or 5 acceptors.
Bottom Line #3 - I'm not motivated. It is an "If I knew then what I know now..." situation back 10 to 15 years when iwas more motivated I didn't understand the topic with sufficient confidence.
 
Formal quals in Civil and Military Engineering, Training, Law. The most relevant expertise arising from (a) breadth of technical experience (b) practice at explaining complex technical issues to lay person audiences of the type Thomas B has in mind AND (c) I've already written many chapters of the book in on-line discusions. EITHER targetted at lay persons or at about undergraduate level which would need "translation down".

I'm not a professional writer and I would need a good editor watching over my shoulder.

Bottom line #1 - I would always prefer face to face - either one-on-one or small group rather than a "Book" which would need to predict questions and topic scope.
Bottom line #2 - I doubt there is a market. I've been offering to explain details for many years and only about 4 or 5 acceptors.
Bottom Line #3 - I'm not motivated. It is an "If I knew then what I know now..." situation back 10 to 15 years when iwas more motivated I didn't understand the topic with sufficient confidence.
That sort of teaching is what the Socrates advocated. It allows the student to almost guide their own enlightenment... a book can't really do that.
 
It's a beyond a train wreck for the old standards of Metabunk. I think that is what econ is (understandably) having a hard time processing. Although eventually Mick might throw this thread into "Open Discussion" where it belongs.
Historically 9/11 threads have tended to ramble. But after the first page, only the participants are likely to read any of it. Consider the epic thread: "9/11: Is this photo consistent with a progressive collapse?" which I eventually locked after 2.5 years. No great harm was done, but I think much time was wasted.

https://www.metabunk.org/threads/9-11-is-this-photo-consistent-with-a-progressive-collapse.364/
 
Historically 9/11 threads have tended to ramble. But after the first page, only the participants are likely to read any of it. Consider the epic thread: "9/11: Is this photo consistent with a progressive collapse?" which I eventually locked after 2.5 years. No great harm was done, but I think much time was wasted.

https://www.metabunk.org/threads/9-11-is-this-photo-consistent-with-a-progressive-collapse.364/

: ) which goes to Thomas's complaint that it's too hard to find info online conveniently. (Not that i expect you to untangle the quagmire that is the 9/11 forum.. it would be easier to write the book Thomas is asking for!)
 
I am guilty of raising the issue of details in this discussion. And I think the details may be at least ONE of the impediments to both "universal" understanding and acceptance of that understanding. There is consensus about the knowable... the design structure, the principles of engineering, physics, fire and materials science. Then we enter the area of less certainty as it relates to the quantity and location of energy inputs into the structure which resulted in the destruction/collapse of the three towers. So what we have seen is rigorous what I would call best guesses by scientists and engineers to apply the assumed values and locations of the energy to the known science/engineering and structure... essentially turning a black box into a glass box!

NIST has the most broadly accepted theory of collapse. The "web" has seen all sorts of theories advanced most with little to no universal support probably in large part due to "lack of authority".

Perhaps the key take-away or maybe the elephant in the room is... the notion that the buildings stood no chance of survival in the face of the magnitude of the energy inputs and so details would hardly matter. The official reports produced sensible conclusions and directives to make tall buildings more survivable... the stated purpose of the investigation.

Does it matter if the total collapse was driven by failing floor trusses or core bracing and columns or failing whatever detail of the towers... for faced with the magnitude of energy applied the outcome was certain. This may be a startling conclusion and a hard pill to swallow.

For me it DOES raise four questions which are interesting and should be addressed in any report.

1. Would the same end (total collapse) come to every high rise facing the same magnitude of energy input?
2. What high rise designs allow more occupants to get out of harm's way? (we know all did in the case of 7wtc)
3. Were there features of the twin tower designs which enabled the outcome or allowed that outcome to occur more quickly and with more loss of life?
4. If the answer to 3 is yes, what should be done about existing high rises that share those features or designs yet to be built?

It is noted that jumbo jet strikes are way out of spec for high rise design. But also noted is that fire seems to be the driver of all three collapses and the twin towers survived the plane strikes.

And this raises yet another question... Can fire protection be changed or increased to make high rises survive uncontrolled fires? What would that look like and cost and can these changes be retrofitted to existing buildings?
 
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