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[W:57: 1585]Evidence that 9/11 was an inside job.

@CLAX1911 - Those are some good insights into the psychology of conspiracy theory "beliefs". Just a couple or 3 comments (EDIT: OK - make that seven ;) ):

1 ..and I suggest there is also a common underlying cause. Put simply it is "blind spotting" - the inability to comprehend that there can be many things beyond our comprehension. I'll comment further later in the post.
2 Agreed - we are safe enough if we are self aware and stay within our limitations. Those who are not self aware and go outside their limits are the ones you are referring to. And - of course - our range/scope/limits vary widely.
3 Yes. If you are within your limits than you can legitimately know" they are wrong. The risk is that any of us MAY not be accurately aware of our limits.
4 The converse of the previous - they are outside their limits and not aware of it for the reasons you describe.
5 Agreed those are important factors.
6 ... That is a key point although I'm using it from a different perspective than your post. See the concluding paragraph.
7 OR - my version - when the problem in in pathological psychology there is no point arguing technical facts of physics. CT belief is almost always indeendent f the specific issue under debate. "truthers" are first and foremost conspiracy theorists. "9/11 truth" merely the topic ()or one of the topics) that attracts their attention

The issue I regard as driving much constproacy behavior is fefined by a pair of hypotheses: (1) Most conspiracy theorists cannot think; AND (2) That is why most of them became conspiracy theorists. Where "think" ot "thinking" refers to the process of convergent reasoning needed to resolve complex muilti-factor problems. The evidence of "don't think" litters these threads. "cannot think" not as obvious but that is a topic for another time. I've explained in more detail in other Forums but the limited reasoning skill builds a defence mechanism of blame - with "authority", "the man", "Government" as obvious targets for blame. Again a topic for discussion in another place and time.

Sometimes there is something outside of them selves prohibiting the thought process. I remember a supervisor at a place I used to work here had this idea that the world was going to end in a month. Mentioned it to another friend and this other friend said he was a Jahova's witness. I took my friend's word for it because he had left the Jahova's witness church.

Sometimes things like that can cause this.
 
Yes. I was responding to Sander, about how the floor system engages with the core area.
Yes - whilst avoiding defining what stage of collapse you are talking about whilst SanderO was explicitly clear.

So you "quote-mined" what he said THEN made two assertions - one false and the other irrelevant viz:
Assertion #1
If the core perimeter belt truss failed the slab wouldn't go with it.
Which is FALSE in the context of SanderO's statement for the reasons I gave. In the progression stage the driving force for shearing floor joist or floor beam connections passed THROUGH the concrete slab to cause shearing of the floor joist to column connections - at either end of the OOS floor joist. And the analogous same mechanism in the core.

Assertion #2
The concrete was stronger than the trusses below it.
Which is IRRELEVANT in SanderO's scenario of the progression stage. i.e. what Sander refers to as "ROOSD" and describes as the phase of the stage when "the column axial strength was irrelevant" AND "The runaway floor collapse drive past the columns..." It cannot be much clearer than that. Progression stage and the "ROOSD" mechanism I showed one of the four situations. The other three are analogous.

HOWEVER - Remember my several times offered advice to be clear what part of what mechanism you are referring to. If you really want to discuss it in "initiation stage" be my guest. Discuss the aspect YOU want to support by reasoened argument... there is no need to misrepresent SanderO.
 
Sometimes there is something outside of them selves prohibiting the thought process. I remember a supervisor at a place I used to work here had this idea that the world was going to end in a month. Mentioned it to another friend and this other friend said he was a Jahova's witness. I took my friend's word for it because he had left the Jahova's witness church.

Sometimes things like that can cause this.
Yes - the psychology can be complex. And thank you for the personal example.

From my perspective there is one over-riding factor. The underlying drive towards conspiracy theory obsession lies in the psychology - not in the subject of the obsession. And for many the obsession is so strong that no amount of rational explanation of the (usually technical) topic will convert them.

I have over the past year or two taken to classifying "truthers" - the ones I regard as genuine truthers - not trolls or game players - into two classes. viz:
"Class #1" - those who hold genuine concerns but can respond to reasoned argument and override any tendency they may have towards CT. << Put crudely they are persuadable, "winnable" or "can be converted". There are very few Class #1 Truthers still active;
AND
"Class #2" - those whose concerns are driven by obsession. And who put their obsession ahead of reason. << Whilst they put obsession first they will set aside rational argument. These are the commonest class of truthers still active in discusion.

And BTW - a related issue - those Class #2 Truthers are not "liars" because they genuinely hold the false beliefs subject of their obsession. And genuine belief in an untruth is a defence against accusations of lying.
 
Yes - the psychology can be complex. And thank you for the personal example.

From my perspective there is one over-riding factor. The underlying drive towards conspiracy theory obsession lies in the psychology - not in the subject of the obsession. And for many the obsession is so strong that no amount of rational explanation of the (usually technical) topic will convert them.

I have over the past year or two taken to classifying "truthers" - the ones I regard as genuine truthers - not trolls or game players - into two classes. viz:
"Class #1" - those who hold genuine concerns but can respond to reasoned argument and override any tendency they may have towards CT. << Put crudely they are persuadable, "winnable" or "can be converted". There are very few Class #1 Truthers still active;
AND
"Class #2" - those whose concerns are driven by obsession. And who put their obsession ahead of reason. << Whilst they put obsession first they will set aside rational argument. These are the commonest class of truthers still active in discusion.

And BTW - a related issue - those Class #2 Truthers are not "liars" because they genuinely hold the false beliefs subject of their obsession. And genuine belief in an untruth is a defence against accusations of lying.

I think there's part of it that has to do with In crowd or being read into something. When a conspiracy theorist runs into another conspiracy theorist they often congratulate one another on being enlightened.

I pay attention to these things because they fascinate me. If I had stayed with psychology I would have probably studied this. But it's almost like the in group concept with regard to a cult. So I think there's part of it that's belonging to something.
 
I think there's part of it that has to do with In crowd or being read into something. When a conspiracy theorist runs into another conspiracy theorist they often congratulate one another on being enlightened.

I pay attention to these things because they fascinate me. If I had stayed with psychology I would have probably studied this. But it's almost like the in group concept with regard to a cult. So I think there's part of it that's belonging to something.
Understood and agreed. My own qualifications are in Engineering - Civil by long term career involvement and Military through 15 years AU Army Reserve. Plus I have a law degree but have never practised law.

However the two areas which are more relevant to those discussions - organisation management of engineering based services and a lot of conflict resolution - staff relations, industrial and customer relations. Plus interface to the political arena on policy matters.

So I find it interesting explaining and keeping people on track when they lose the plot - and that is certainly the situation with technical aspects of 9/11 such as WTC. This thread a classic example - as I said once on another forum '"How many leaves on the seventh branch of the fourth tree?" is meaningless when you are in the wrong forest.'

What brought me to online discussion was when a colleague asked me what I thought of the CD of the Twin Towers. And I laughed before I realised he was serious. Then for reasons of personal credibility and local town politics I had to give him a top level professional answer. He was son-in-law of the Mayor of the town and I was City Engineer... :3oops: :roll:
 
Understood and agreed. My own qualifications are in Engineering - Civil by long term career involvement and Military through 15 years AU Army Reserve. Plus I have a law degree but have never practised law.

However the two areas which are more relevant to those discussions - organisation management of engineering based services and a lot of conflict resolution - staff relations, industrial and customer relations. Plus interface to the political arena on policy matters.

So I find it interesting explaining and keeping people on track when they lose the plot - and that is certainly the situation with technical aspects of 9/11 such as WTC. This thread a classic example - as I said once on another forum '"How many leaves on the seventh branch of the fourth tree?" is meaningless when you are in the wrong forest.'

What brought me to online discussion was when a colleague asked me what I thought of the CD of the Twin Towers. And I laughed before I realised he was serious. Then for reasons of personal credibility and local town politics I had to give him a top level professional answer. He was son-in-law of the Mayor of the town and I was City Engineer... :3oops: :roll:

Yes you have to be careful with conspiracy theorists that you work around. With the ones I have to work with I typically actors though I've never heard of it and that the information they give is new to me. This seems to make them happy. And quite honestly I'm fascinated with how the human mind works. I find a lot of people quite irritated with it which also fascinates me.

These days I I'm getting into metallurgy. And I remember speaking to somebody about to steal being vaporized. Now I've actually vaporized steel before into the pictures he was showing me couldn't have been of vaporized steel. Though he was claiming it was. I asked at this particular poster some questions about metallurgy at such temps and his knowledge seemed lacking.
 
Yes you have to be careful with conspiracy theorists that you work around.
Here in AU I've only met that one 9/11 Truther type CT face to face. I currently have a couple of anti-vax and health faddist CT friends. In my own professional background I've had to deal with water supply related CTs - anti-fluoride being one. And a less contentious one - use of chlorine for water disinfection. All three of those draw on the same basic ignorance of risk management statistics - the choice to do the best you know for 99% with some risk to 1%. The anti-vaxers would risk 99 to posibly save 1 << the odds are different in practice but still overwhelming one way versus real but small the other way. And often the downside not known.

These days I I'm getting into metallurgy. And I remember speaking to somebody about to steal being vaporized. ....I asked at this particular poster some questions about metallurgy at such temps and his knowledge seemed lacking.
It isn't hard to find the limits of understanding - on both "sides" of this ridiculous false dichotomy of "only two sides" polarisation. And across all the fields of applied physics - structural mostly, but metallurgy and thermodynamics. Also the 3D + T spatial stuff in WTC collapse and the aeronautical aspects.

Then across all of it the near universal problem of "starting argument from the wrong end" - trying to wok "upwards" from the bit of anomaly the truther doesn't understand. Rather than work from known facts of the bigger picture and only digging into detail when necessary. The other problem - which has also surfaced in this thread. Trying to put numbers on some problem when you don't have a clue what you are trying to quantify.

Then the immediate problem in the technical discussion in this thread - trying to apply a detail from one part of the WTC collapse to another totally different pert of the collapse. When the conclusion is both false and irrelevant in EITHER situation.
 
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Yes - whilst avoiding defining what stage of collapse you are talking about whilst SanderO was explicitly clear.

So you "quote-mined" what he said THEN made two assertions - one false and the other irrelevant viz:
Assertion #1

Which is FALSE in the context of SanderO's statement for the reasons I gave. In the progression stage the driving force for shearing floor joist or floor beam connections passed THROUGH the concrete slab to cause shearing of the floor joist to column connections - at either end of the OOS floor joist. And the analogous same mechanism in the core.

Assertion #2

Which is IRRELEVANT in SanderO's scenario of the progression stage. i.e. what Sander refers to as "ROOSD" and describes as the phase of the stage when "the column axial strength was irrelevant" AND "The runaway floor collapse drive past the columns..." It cannot be much clearer than that. Progression stage and the "ROOSD" mechanism I showed one of the four situations. The other three are analogous.

HOWEVER - Remember my several times offered advice to be clear what part of what mechanism you are referring to. If you really want to discuss it in "initiation stage" be my guest. Discuss the aspect YOU want to support by reasoened argument... there is no need to misrepresent SanderO.

Ozeco - i responded to something on the page - if you don't like that just put me on ignore.

As far as bowing columns are concerned, what you need to do is point me to one of the many examples that you said were out there, and let me know which column at which storey we are analysing. You said there were a lot of examples out there. Link me to one.
 
Ozeco - i responded to something on the page - if you don't like that just put me on ignore.

This is a discussion forum. People are going to respond. Your stance just indicates to me you don't like it when posters show possible errors in your opinion/view.

You have totally missed the point Oz has presented to you.
 
Your stance just indicates to me you don't like it when posters show possible errors in your opinion/view.

You have totally missed the point Oz has presented to you.

Agreed.
 
When are you going to get round to the evidence for an inside job?
 
I believe the understanding begins with accurate observations (of the movement/changes to the building). However understanding also requires technical knowledge. For example someone could precisely describe a cloud... but without understanding of gas laws, meteorology and so on... the observer couldn't possibly accurately understand why the clouds looked and behaved as they did. All / any explanation... on any level - detail or gross must honor the laws of mechanics (physics), structural engineering (applied physics) and materials science. For sure this makes it very difficult to impossible for naive, uneducated people to understand what they saw. But it has nothing to do which what they think they saw and why it happened.
 
When are you going to get round to the evidence for an inside job?
I agree the PRINCIPLE of staying on topic. So several times over recent days I have gone back to the OPost to check the OPoster's intent.

The thread title is a bit misleading - here is what the relevant bits of the OPost say:

I decided to start a thread to ask for evidence that 9/11 was an inside job.....I'm more than willing to return to believing that 9/11 was an inside job if presented with irrefutable evidence. I'll start off with the claim that the towers feel at free fall speeds.....the debris from the tower is actually falling faster than the tower itself. Thus supposedly disproving the free fall claim. Any counter to this?

So Maccabee wanted to review the technical evidence as his first step approaching the topic of "inside job".

I came late to the thread and found that the technical debate was deep down a rabbit burrow going nowhere other than round in circles. So I suggested taking a more rational approach to understanding that technical realities. (See my posts # et seq.)

At the present rate of progress discussion of inside job MAY start before the end of this year. ;) :peace
 
I agree the PRINCIPLE of staying on topic. So several times over recent days I have gone back to the OPost to check the OPoster's intent.

The thread title is a bit misleading - here is what the relevant bits of the OPost say:



So Maccabee wanted to review the technical evidence as his first step approaching the topic of "inside job".

I came late to the thread and found that the technical debate was deep down a rabbit burrow going nowhere other than round in circles. So I suggested taking a more rational approach to understanding that technical realities. (See my posts # et seq.)

At the present rate of progress discussion of inside job MAY start before the end of this year. ;) :peace

Hope springs eternal in the human breast!
 
As far as bowing columns are concerned, what you need to do is point me to one of the many examples that you said were out there, and let me know which column at which storey we are analysing. You said there were a lot of examples out there. Link me to one.
You have the gall to ask "which storey?" when you are the one who is confusing two different stages of collapse - which stages identify the storey or range of stories that are relevant. AND after I have several times clearly and explicitly identified your confusion and indicated the way towerds clearer thinking.

Your reading comprehension cannot be as poor as you are pretending. PLUS your repetition of the false assertion "You said there were a lot of examples out there." I made no such statement and your repetition of the deliberate untruth is boring.

Ozeco - i responded to something on the page - if you don't like that just put me on ignore.
I have shown you clearly where your technical analysis is in error. Also why your reasoning process is doomed to go nowhere. I have no need to attempt to assist you further since you are not interested in learning from discusion.

However you do not "own" the thread and I may need to comment further.
 
Hope springs eternal in the human breast!
I become increasingly pessimistic as the years pass.

Yesterday I had a need to refer to a post I made on this forum back in 2013. One of my first posts here. And a deliberate essay at a moderately high technical level. I must have been well on target with my comments because Henry David as he then was saw fit to ridicule it. Always a positive sign. Sure - as a "newbie" I was sort of "calibrating". I then read a number of subsequent posts reflecting on the dire status of serious discussion THEN - 2013.

This is the post
Was "Global collapse truly inevitable"?

- but the interaction with mike2810 and the then resident troll "menard_k" in subsequent posts show that little has changed.
 
BTW - the reference to mike2810in the previous thread was positive. This is part of what he said back in 2013:
ozeco41

Thanks for bringing some sanity to this forum. ... It is good to see rational posts again.

We still need some "rational posts". Hence my comment about "little has changed".
 
BTW - the reference to mike2810in the previous thread was positive. This is part of what he said back in 2013:


We still need some "rational posts". Hence my comment about "little has changed".

I agree not much has changed on this site. I did catch some of your posts on the skeptic site.
Tactics by some have not changed over the years. Always the reverse burden of proof when you call them on their statements.
Missed your posts here. Glad your back, at least for awhile I hope.
 
... Missed your posts here. Glad your back, at least for awhile I hope.
I've been trying to stop this hobby for some time. Serious debate died on most forums from about 2015 but I lacked the determination to go "cold turkey" into withdrawal from the game. Then about 3 years back a colleague asked me to move to FaceBook where an engineer truther wanted a discussion with a "real engineer". So I joined the group and posted a brief CV of my attributes for the job. I planned on using it as a "withdrawal tactic" sort of "on-line Methadone" to break the addiction. Didn't work. And the challenging truther disappeared over the horizon in a cloud of dust. But I found that there was some real discussion on FB. Sure lower level and 3-4-5 years behind the forums. But "Beggars can't be choosers".

But I kept monitoring the forums including this one. And lo and behold - I saw this thread - a 2007-8-9 era bit of debate getting lost in details. So I couldn't resist the temptation.

Silly me.

The only other slightly active technical discussion on other forums is about the Hulsey AE911 scam project at UAF. And that discussion frustrates me a lot. Hulsey making a fundamental error of base logic - he claims he can "Prove that Fire could Not Cause WTC7 Collapse". And that is not possible - he CANNOT prove the global negative "could NOT". But all the engineering and physics types are busy showing that Hulsey got his engineering wrong. [/EndRant]

I've made that point on every forum and FaceBook group and no-body wants to know. And it is the same point I made about T Szamboti in my very first Internet post 14 Nov 2007...[/EndSecondRant]

And - as I'm sure you will have spotted - it is the same type of error as I"ve commented on in this thread. viz focusing on and arguing about details when the fundamental logic AND process is wrong.
 
I believe the understanding begins with accurate observations (of the movement/changes to the building).
Agreed SanderO. Provided we take care to avoid the trap one of our colleagues makes far too often. The need is for ACCURATE but that does not mean precise or multiple decimal places numeric. In fact "engaging the numbers BEFORE knowing what you are applying them to" is one of the commonest errors made in the applied physics aspects of these discussions.

The most important "accurate observation" for the recent discussion this thread is that the Twin Towers collapses...both of them... were in definite stages. Because the feature of inward bowing occurred specifically in the "initiation stage" and trying to explain it as if it occurred in the "progression stage" is pure nonsense.
 
Inside job, seriously? People actually believe that nonsense.

OK the Government has been involved in some rather disturbing and nefarious **** over the years, the US led Tuskegee and Guatemala syphilis experiments on humans comes to mind, but 911, come on.

The buildings fell in that manner because they were designed to fall that way to protect neighboring buildings. The weight of the floors crashing upon each other, with seconds to give way, made it look like a controlled demolition.

Americans are too involved in conspiracy theories. Get a grip.
 
I've been trying to stop this hobby for some time. Serious debate died on most forums from about 2015 but I lacked the determination to go "cold turkey" into withdrawal from the game. Then about 3 years back a colleague asked me to move to FaceBook where an engineer truther wanted a discussion with a "real engineer". So I joined the group and posted a brief CV of my attributes for the job. I planned on using it as a "withdrawal tactic" sort of "on-line Methadone" to break the addiction. Didn't work. And the challenging truther disappeared over the horizon in a cloud of dust. But I found that there was some real discussion on FB. Sure lower level and 3-4-5 years behind the forums. But "Beggars can't be choosers".

But I kept monitoring the forums including this one. And lo and behold - I saw this thread - a 2007-8-9 era bit of debate getting lost in details. So I couldn't resist the temptation.

Silly me.

The only other slightly active technical discussion on other forums is about the Hulsey AE911 scam project at UAF. And that discussion frustrates me a lot. Hulsey making a fundamental error of base logic - he claims he can "Prove that Fire could Not Cause WTC7 Collapse". And that is not possible - he CANNOT prove the global negative "could NOT". But all the engineering and physics types are busy showing that Hulsey got his engineering wrong. [/EndRant]

I've made that point on every forum and FaceBook group and no-body wants to know. And it is the same point I made about T Szamboti in my very first Internet post 14 Nov 2007...[/EndSecondRant]

And - as I'm sure you will have spotted - it is the same type of error as I"ve commented on in this thread. viz focusing on and arguing about details when the fundamental logic AND process is wrong.

I am waiting for the release of the Hulsey report. From what has been released I see some issues with how fire was applied in the model. From what I have seen of his presentations his fire modeling is not as accurate as NIST modeling.

No one knows for sure the rate of spread of the fire, heat transfer / energy release rate of the fire, exact fuel loading, etc. While fire behavior models have improved they still do not represent the real world. There are just too many factors to consider.
 
I am waiting for the release of the Hulsey report. From what has been released I see some issues with how fire was applied in the model. From what I have seen of his presentations his fire modeling is not as accurate as NIST modeling.

No one knows for sure the rate of spread of the fire, heat transfer / energy release rate of the fire, exact fuel loading, etc. While fire behavior models have improved they still do not represent the real world. There are just too many factors to consider.
No need to wait for the report. His claim "fire could NOT" is not sustainable - he cannot prove that assertion. Now reverse the polarity and he may be able to prove "CD help was not needed" - I can support "CD not needed" for the Twin Towers. That avoids the two closely related logical traps Hulsey has set himself. The first - the general issue of "cannot prove a negative... the second - he cannot falsify all the potential fire could do it scenarios.

There are MANY problems with his engineering but the fundamental and over-riding error is in the foundation of his logic. It is not possible to prove "fire could not cause collapse" in the WTC7 situation. The only way he can prove that global negative is if he demonstrates it for every possible scenario. And he has only done a limited set of scenarios. If there are 26 possibilities a, b, c, d, ....thru z and he tests a, b, d, p, q, r and x he cannot show that the actual one was NOT j or t or v. So all he can legitimately claim is "None of the scenarios I have tested cause collapse." He cannot prove that there is no fire causes collapse scenario...or in fact several. I doubt it is possible to even identify all scenarios but I'm not sure of that aspect.

Sure there are problems at the level of engineering details. So he could well be "doubly wrong" ;):roll:
 
Inside job, seriously? People actually believe that nonsense.
These days it is hard to tell who actually "believes" and who is simply playing games.

However there is a serious aspect of so-called "inside job" that IMNSHO has not been given sufficient consideration.

The general idea that 9/11 was 100% totally organised by US agency is of course 99.9% certainly wrong.

However the debate has focussed on two ideas identified by the acronyms "MIHOP" and "LIHOP" - meaning "Made It Happen On Purpose" or "Let It....."

Where "IT" is presumed to be the whole thing as a single homogeneous entity.

There are three big problems with that form of debate:
1) It misses the other big option which is "LIHOOI" - Let It Happen Out Of Incompetence >. and the fact that 9/11 happend means US Government did nor prevent it therefore prima facie that is "LIHOOI";
2) There were almost certainly lots of aspects of mis - mal - and non feasance among the levels of US Government and its agencies. >> Lack of co-operation CIA <> FBI acknowledged. Some of that due to inappropriate rules. Some due to rivalry and "turf protection ". And these aspects at all levels from agency rivalry down to individual officer incompetence.

So - does it all matter now - 17+ years later?

I say Yes!! but for a reason that many have still not recognised. It is this major error by the truth movement.

3) The truth movement - with AE911 the worst and most prominent offender - has kept the focus of debate on false technical claims. In AE911's case the goal is to maintain R Gage's income and ego tripping. And keeping the focus on false technical claims such as CD at WTC - their central ploy or infighting over planes or no-planes at Pentagon has ensured no serious intelligent debate of the political issues. Not just "inside job" stupidly defined as "all of IT" but the more complex issues of geo politics with examples being the depth and seriousness of involvement by Israeli and Saudi interests.

So there is a whole topic area worthy of discussion. Not so much "inside job" as conventionally defined as "The US Government did IT" - but addressing the real and complex political issues. Both inter-agency domestic and international geo politics.

But truthers who cannot even now comprehend simple reality - there was no CD no need for CD at WTC - are not the level of intellect needed to discuss the far more complicated issues in the domain of politics - both little "p" and big "P"..

So....
Americans are too involved in conspiracy theories. Get a grip.
Whilst I agree I take a different perspective on what needs "gripping". ;)
 
Agreed SanderO. Provided we take care to avoid the trap one of our colleagues makes far too often. The need is for ACCURATE but that does not mean precise or multiple decimal places numeric. In fact "engaging the numbers BEFORE knowing what you are applying them to" is one of the commonest errors made in the applied physics aspects of these discussions.

The most important "accurate observation" for the recent discussion this thread is that the Twin Towers collapses...both of them... were in definite stages. Because the feature of inward bowing occurred specifically in the "initiation stage" and trying to explain it as if it occurred in the "progression stage" is pure nonsense.

Correct... each stage had defining characteristics. But there were transitions from on stage / set of processes to the next. I suspect this is probably the the fuzzy part for people trying to explain the entire event. And these phase/stage transitions were hard to see. often taking place inside behind the facade. 7WTC illustrates this problem. There were structural failures INSIDE the tower which led to the collapse of the EPH... can't see these. When the building dropped etc... it did so because something happened some place (low) inside the building... but this something is pretty much hidden from view. People look for things like characteristics of smoke... or the tower leaning etc. We can't see if the inside collapsed before the moment frame and curtain wall came down. Likewise the behavior of the facade (peeling away) and the expulsions of dust and debris proceeding down the building are the tells that the floors are crashing down in the twin towers. The speed of collapse/descent of the floors can be calculated from the descent down the facade of the expulsions... including the "fact" that the floor collapse was not uniform plates or pancakes...

It also may be, likely is.. that the phase / stage transitions may be explained by multiple failures / changes in the structure and there may not be a unique sequence...to explain these transitions... that is the say it's like all (many in this case) roads lead to Rome. Perhaps the discussion should be how did the structural design assists or resists the sequence of failures in the phase / stage transitions. Again, I would argue, for example that the transfers in floors 5 - 7 assisted in the phase transition to the building/s "release" and rapid collapse. My take away is that one needs to understand the main structural design concepts/elements employed in the towers to explain or understand what is observed. All three of these buildings were notably different structural approaches / elements / attributes from most high rise buildings.
 
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