Also, Bin Laden had nothing to do with it and possibly is a swell guy who loves kittens and donates his time to the poor children down at the Boys and Girls Club.
Did Bush watch plane hit the first tower ?
- Thread starter Non Believer
- Start date
Also, Bin Laden had nothing to do with it and possibly is a swell guy who loves kittens and donates his time to the poor children down at the Boys and Girls Club.
I never thought I'd say this, but yeah he kind of is.
They both refuse to examine any evidence at all, but Chris is just slightly nicer about it.
Non Believer
Critical Thinker
- Joined
- Dec 2, 2006
- Messages
- 257
Nothing new, as we have been through all this before. As Fezzic (and those before him) says we cannot consider the lower portions ability to hold the collapsing portion because of the weakness at the floor trusses. Fine, except that this theory leads to the pancake collapse that NIST rejected, so you are back to where you started from.
Cl doesn't get it, or is angry by the explanation. Who knows, and who cares. The point is that you are calculating the explosive force with a mass that the structure has been supporting, so to make it sound that it is suddenly facing a new force is absurd. Also how do you apply free fall acceleration unless you assume the energy beam that cuts through the entire building simultaneously.
One other thing-Someone asked why all these engineers and such could come to the wrong conclusion. This is quite clear. You start with a belief of what happened (collapse caused by plane crash and fires), and then you do your best to fix the facts to explain that phenomenon. It does not mean that they mislead us in any intentional way. It is much more likely the case that they believe this must have happened, so they are willing to constantly fudge the criteria in the direction favorable of a collapse.
For example, You are trying to determine the temps of the fires. Most of the physical evidence (paint tests, model results, etc.), indicates temps below 600F, but these temps don't result in initial collapse in your computer models. But you KNOW that the impact damage and fires brought down the building, so you decide the physical evidence must be wrong to some degree and you plug in higher temps.
Again when it comes to global collapse. You just decide that since the building came down that this means automatically that initial collapse would lead to global. It is not surpassing that those on this forum are not capable of breaking free of this analytic pathology since they are not able to even discuss their objectivity.
Though, I must backtrack a little and insist that you have not shown the amount of assent to official story as you claim. I have asked for evidence of the support among experts for the official story, but have never seen such evidence. Further, just because somebody works on the NIST report does not mean that their opinion is consistent with the conclusions of the report
Cl doesn't get it, or is angry by the explanation. Who knows, and who cares. The point is that you are calculating the explosive force with a mass that the structure has been supporting, so to make it sound that it is suddenly facing a new force is absurd. Also how do you apply free fall acceleration unless you assume the energy beam that cuts through the entire building simultaneously.
One other thing-Someone asked why all these engineers and such could come to the wrong conclusion. This is quite clear. You start with a belief of what happened (collapse caused by plane crash and fires), and then you do your best to fix the facts to explain that phenomenon. It does not mean that they mislead us in any intentional way. It is much more likely the case that they believe this must have happened, so they are willing to constantly fudge the criteria in the direction favorable of a collapse.
For example, You are trying to determine the temps of the fires. Most of the physical evidence (paint tests, model results, etc.), indicates temps below 600F, but these temps don't result in initial collapse in your computer models. But you KNOW that the impact damage and fires brought down the building, so you decide the physical evidence must be wrong to some degree and you plug in higher temps.
Again when it comes to global collapse. You just decide that since the building came down that this means automatically that initial collapse would lead to global. It is not surpassing that those on this forum are not capable of breaking free of this analytic pathology since they are not able to even discuss their objectivity.
Though, I must backtrack a little and insist that you have not shown the amount of assent to official story as you claim. I have asked for evidence of the support among experts for the official story, but have never seen such evidence. Further, just because somebody works on the NIST report does not mean that their opinion is consistent with the conclusions of the report
I am not an engineer nor do I play one on TV. But an engineer (or scientist) who makes an assumption and then adjusts the facts to fit it is a lousy engineer (scientist).
Or a CTist.
Idiot Proof Posting for Non Believer
Now NB, this is going to be a rather long post but I'd like you to read it and tell me where you disagree:
1. The principal design loads encountered in a tall building such as WTC are the dead load (the weight of the materials themselves), the live load (occupants and contents), and wind loads.
2. Even comparatively limited wind speeds can produce significant loads, because of the surface area, and it is important to appreciate that they will result in significant strains on the building; deflection is not constant across a face, raising torsional issues, the lee face will be in compression whilst the windward might be in compression, and so on.
3. It would be neither practical or economic to have one element carry all those loads; for example, the external envelope would have to comprise massive sections and cross bracing. The traditional (well, post-Louis Sullivan) approach has been a framed structure with frequent columns across the floor plate braced by large beam sections at floor level. Unfortunately this results in a significant loss of floor space and hence lower rental returns.
4. WTC therefore adopted what might be loosely termed a composite approach, with three principal structural elements acting together. A layman's comparison would be a space frame, which is far lighter and more efficient than a steel beam would be for the same loading.
5. The outer loadbearing facade comprised comparatively slim box sections, with staggered joints. This envelope carried the outer end of the floors (and hence around half the dead/live loads) and also the wind loadings.
6. The inner core comrpised section columns. These were significantly larger than the individual box sections because individually they were carrying greater loads (i.e. same or slightly larger loads, but less columns as available perimeter was less). In addition the core provided resistance to the bending moment caused by wind loads.
7. Of course for this system to work, it is necessary to transmit the loads betwixt the facade and the core. This was the work of the floor trusses, which redistributed wind loads (like a space frame) AND transmitted the dead/live loads to the other two elements.
8. An additional - and rather cute - feature of the design was the use of the so called hat trusses at high level; if you can imagine the bending moment in a high wind, one of the areas of greatest stress is at high level, and these trusses effectively acted as a very much beefed up version of the floors, stiffening the whole upper structure together and redistributing loads.
9. This is what Robertson - and the others - all mean when they say:
11. Now, clearly the floor is supported at both ends and the loads largely distrbuted evenly (saving for allowance for the corners) between the outer facade and inner core. Similarly we know that cantilevering the floors from the core alone would be impractical due to cross-sectional sizes. Hence it is entirely wrong to suggest that the core was designed to take all floor loadings.
12. For a summary of mutch of the design, you might want to start with the FEMA report at http://www.fema.gov/pdf/library/fema403_ch2.pdf .
13. On 911, the aircraft impacts caused damage to the cores through both connection (splice) failure and fracturing of the columns themselves. At WTC1 6 columns failed completely and 9 suffered significant damage. At WTC 2, 10 failed completely and 7 were badly damaged.
It is obvious that this would have compromised the ability of the core to carry loads.
14. We similarly know that there was damage to the external frame, compromising its ability to carry load.
15. You have questioned the intensity of the fire and effect on the floors. Now one of our best resources is the extensive NIST fire modelling, but I suspect you're going to claim that the results were fiddled so instead let's have a look Eagar's 2001 article - http://www.tms.org/pubs/journals/JOM...agar-0112.html and his February 2002 presentation -http://eagar.mit.edu/EagarPresentati...C_TMS_2002.pdf.
One of the first things his article inadvertently does is rubbish suggestions that smoke colour indicated a minor fire.
He then goes on to deal with failure of steel due to "normal" office fires:
and
which means:
Before coming to the conclusion that:
16. We know that failure of the lightweight floor trusses led to buckling of the external facade over a significant area, to the point where the affected section could no longer carry any dead/live loads.
17. Some of this load was redistributed to adjacent external panels through the staggered jointing system (think of it as a natural arching structure) and some to the damaged inner core by way of the hat trusses. Neither had sufficient capacity to accept these loads, and failed - thus initiating the collapse.
18. The collapse of the floors and outer envelope would invariably lead to impact damage on the already weakened core. Whilst it is mass that would cause damage, it is nevertheless important to note that large sections of relatively intact debris can be clearly identified in photographs.
19. Similarly it is important to understand that the impact loads would not have been uniformly vertical. We know that parts of the structure tilted and rotated, placing transverse dynamic loads on the structure below. But the core was not built to accept transverse loads in isolation, only as part of the wider composite system. There would be little or no effective bracing.
20. In the same vein, the floors themselves were attached to the core and it would be niaive to believe that when dislodged the joints would neatly shear. Some damage to the core columns would be inevitable.
21. However this is largely academic as the outer envelope and core failed in quick succession as a result of redistributed loads.
Now, NB. Which bits of this do you disagree with, and why? Remember to provide a detailed response for a change.
Now NB, this is going to be a rather long post but I'd like you to read it and tell me where you disagree:
1. The principal design loads encountered in a tall building such as WTC are the dead load (the weight of the materials themselves), the live load (occupants and contents), and wind loads.
2. Even comparatively limited wind speeds can produce significant loads, because of the surface area, and it is important to appreciate that they will result in significant strains on the building; deflection is not constant across a face, raising torsional issues, the lee face will be in compression whilst the windward might be in compression, and so on.
3. It would be neither practical or economic to have one element carry all those loads; for example, the external envelope would have to comprise massive sections and cross bracing. The traditional (well, post-Louis Sullivan) approach has been a framed structure with frequent columns across the floor plate braced by large beam sections at floor level. Unfortunately this results in a significant loss of floor space and hence lower rental returns.
4. WTC therefore adopted what might be loosely termed a composite approach, with three principal structural elements acting together. A layman's comparison would be a space frame, which is far lighter and more efficient than a steel beam would be for the same loading.
5. The outer loadbearing facade comprised comparatively slim box sections, with staggered joints. This envelope carried the outer end of the floors (and hence around half the dead/live loads) and also the wind loadings.
6. The inner core comrpised section columns. These were significantly larger than the individual box sections because individually they were carrying greater loads (i.e. same or slightly larger loads, but less columns as available perimeter was less). In addition the core provided resistance to the bending moment caused by wind loads.
7. Of course for this system to work, it is necessary to transmit the loads betwixt the facade and the core. This was the work of the floor trusses, which redistributed wind loads (like a space frame) AND transmitted the dead/live loads to the other two elements.
8. An additional - and rather cute - feature of the design was the use of the so called hat trusses at high level; if you can imagine the bending moment in a high wind, one of the areas of greatest stress is at high level, and these trusses effectively acted as a very much beefed up version of the floors, stiffening the whole upper structure together and redistributing loads.
9. This is what Robertson - and the others - all mean when they say:
11. Now, clearly the floor is supported at both ends and the loads largely distrbuted evenly (saving for allowance for the corners) between the outer facade and inner core. Similarly we know that cantilevering the floors from the core alone would be impractical due to cross-sectional sizes. Hence it is entirely wrong to suggest that the core was designed to take all floor loadings.
12. For a summary of mutch of the design, you might want to start with the FEMA report at http://www.fema.gov/pdf/library/fema403_ch2.pdf .
13. On 911, the aircraft impacts caused damage to the cores through both connection (splice) failure and fracturing of the columns themselves. At WTC1 6 columns failed completely and 9 suffered significant damage. At WTC 2, 10 failed completely and 7 were badly damaged.
It is obvious that this would have compromised the ability of the core to carry loads.
14. We similarly know that there was damage to the external frame, compromising its ability to carry load.
15. You have questioned the intensity of the fire and effect on the floors. Now one of our best resources is the extensive NIST fire modelling, but I suspect you're going to claim that the results were fiddled so instead let's have a look Eagar's 2001 article - http://www.tms.org/pubs/journals/JOM...agar-0112.html and his February 2002 presentation -http://eagar.mit.edu/EagarPresentati...C_TMS_2002.pdf.
One of the first things his article inadvertently does is rubbish suggestions that smoke colour indicated a minor fire.
He then goes on to deal with failure of steel due to "normal" office fires:
and
which means:
Before coming to the conclusion that:
16. We know that failure of the lightweight floor trusses led to buckling of the external facade over a significant area, to the point where the affected section could no longer carry any dead/live loads.
17. Some of this load was redistributed to adjacent external panels through the staggered jointing system (think of it as a natural arching structure) and some to the damaged inner core by way of the hat trusses. Neither had sufficient capacity to accept these loads, and failed - thus initiating the collapse.
18. The collapse of the floors and outer envelope would invariably lead to impact damage on the already weakened core. Whilst it is mass that would cause damage, it is nevertheless important to note that large sections of relatively intact debris can be clearly identified in photographs.
19. Similarly it is important to understand that the impact loads would not have been uniformly vertical. We know that parts of the structure tilted and rotated, placing transverse dynamic loads on the structure below. But the core was not built to accept transverse loads in isolation, only as part of the wider composite system. There would be little or no effective bracing.
20. In the same vein, the floors themselves were attached to the core and it would be niaive to believe that when dislodged the joints would neatly shear. Some damage to the core columns would be inevitable.
21. However this is largely academic as the outer envelope and core failed in quick succession as a result of redistributed loads.
Now, NB. Which bits of this do you disagree with, and why? Remember to provide a detailed response for a change.
aggle-rithm
Ardent Formulist
No, it's supposed to illustrate that your assertions that the towers should not have collapsed are baseless because you don't have enough information to come to that determination.
Here's a better example: I have a substance that melts at a certain temperature. I apply heat. After 30 minutes, is the substance still solid, or has it melted?
By the same logic you are using with the towers, you believe there is sufficient information here to solve the problem. I do not.
aggle-rithm
Ardent Formulist
A ladder is built to handle a dynamic load of several times greater than its own mass.
Were the WTC towers built this way? Can you imagine why they would NOT be built so as to support the weight of, for instance, a 500- to 1000-foot-tall gorilla?
aggle-rithm
Ardent Formulist
Great post, Architect. But I predict his response will be along the lines of:
"Blah, blah, blah, Goedel's incompleteness theorum blah, blah, left brain blah, blah, high school physics blah, blah, blah, conservation of motion blah, blah, common sense."
You forgot to talk about frameworks.
And misspell a couple of the key words. I'm just saying, is all!
We're just playing, Non Believer. We'll be serious as soon as you post actual evidence instead of just flapping your jaw.
aggle-rithm
Ardent Formulist
Well, I did spell "momentum" as "motion".
That's true, but it doesn't have the right typo-ridden flavor of his posts.
Try spelling it "moton" or something. Or "incompleetnuss theerum".
(I'm kidding, I'm kidding)
Regnad Kcin
Penultimate Amazing
"This is quite clear."
Your type really are some of the most amazing people. And I don't mean that in a good way.
Sooner this damned knee gets better and I can find something else to do apart from post and watch daytime TV, the better!
To add to dear aggle's kudos, I as a lowly software type and now bit-shuffler, am in awe, not just of your knowledge, not even close, but to your ability to explain it so I (low ST etc,) can understand it. Thanks, Architect. I know a physicist named Crawford who can do this too. I'm grateful to him, too.
Mr.D
Self Assessed Dunning-Kruger Expert
- Joined
- Jan 3, 2007
- Messages
- 1,178
Non Believer
Critical Thinker
- Joined
- Dec 2, 2006
- Messages
- 257
First off for Jennie- I don't how long you have been following the thread, so perhaps that is part of your difficulty in following the comments. On the other hand, you only mention 2 things I have actually said (Those being Godel and common sense), so I am already a little concerned about your spirit towards real inquiry. It would seem that ridicule is more your concern, though don't be too worried about this criticism since this is the aim of most folks on this forum.
Arch- I am hoping by now you will now what my concerns are about your description of what you believe transpired in the towers on 9-11. So I am to assume your resubmitting of your opinions is one last attempt to get a clarification from me, so I will do my best.
My position is that when I am presented with an argument on a vital subject, that such an argument must reach certain standards of validity. The standard for an opinion of an expert is that the information or theory that expert presents MUST BE VERIFIABLE.
In my opinion your explanation is just a description of what you believe probably happened, and anyone can do that. So as I have stated before, the evidence presented for a certain argument should be judged firstly by that evidences ability to stand alone, and not by the status of the individual presenting the evidence. Such as, can the argument, or hypothesis, be tested in any way. Such tests can include physical models, video evidence, historical precedent, and established scientific precedent. In my opinion, your hypothesis has almost no independent verification.
How am I to differentiate the information you give from the information a person that might be willingly trying to deceive me, or at least willingly keep me in the dark might give. Do you really think a good critical thinker should accept an explanation that is only a description of a belief of what happened to be fact. Do you believe that it could be the case that a single expert or a small group of experts could put forth a claim that is wrong for whatever reason? If the answer is Yes, how am I able to differentiate from what you say with such a person unless the information is independently verifiable.
You offer no qualitative details whatsoever. There is no comment on to how many of the joints, and at what locations failed, to start the collapse. You do not give any indication on how much force the floor trusses could take. You do not give any type of calculation to confirm your position that the floor truss joints could not simply snap free (and not pull on the columns) no matter what the force. This seems surprising since you claim the amount of force this collapse will not even be slowed in the least by the remaining structure below. Do you not think the pulverization of concrete would cause a slowing in free fall collapse?
Beyond the argument that your hypothesis is based on belief and not hard science, you also make the claim that it was well known that the towers were vulnerable to global collapse before 9-11. Yet this is not represented in the recorded history prior to 9-11. We do have clear statements by Skilling and Demartini that they did not expect a collapse. These statements should be considered the official historical expectation, unless you can SHOW quotes that refute them (remember these need to be pre 9-11 to establish historical context). You have failed to do this beyond saying that you knew this was not the case. So we are led back to the original problem of unsubstantiated opinion.
Further, since you seem to have high ideals that only experts should discuss the particulars of the collapse, I am interested at what points do you relinquish your expertise and excuse yourself from the conversation. For instance, when we begin to discuss the lower structures resistance to free fall, this becomes much more a question of physics than engineering. So I assume you will put away your hat as an authority at this point.
For those of you who are the apologetic grammar critics, please don't concern yourselves with my feelings on the matter. I certainly feel it is all of you that should be concerned about the embarrassment of stooping to such criticisms. Believe it or not, many of you make typos or real mistakes as well, but I try to concentrate on the ideas being discussed.
Arch- I am hoping by now you will now what my concerns are about your description of what you believe transpired in the towers on 9-11. So I am to assume your resubmitting of your opinions is one last attempt to get a clarification from me, so I will do my best.
My position is that when I am presented with an argument on a vital subject, that such an argument must reach certain standards of validity. The standard for an opinion of an expert is that the information or theory that expert presents MUST BE VERIFIABLE.
In my opinion your explanation is just a description of what you believe probably happened, and anyone can do that. So as I have stated before, the evidence presented for a certain argument should be judged firstly by that evidences ability to stand alone, and not by the status of the individual presenting the evidence. Such as, can the argument, or hypothesis, be tested in any way. Such tests can include physical models, video evidence, historical precedent, and established scientific precedent. In my opinion, your hypothesis has almost no independent verification.
How am I to differentiate the information you give from the information a person that might be willingly trying to deceive me, or at least willingly keep me in the dark might give. Do you really think a good critical thinker should accept an explanation that is only a description of a belief of what happened to be fact. Do you believe that it could be the case that a single expert or a small group of experts could put forth a claim that is wrong for whatever reason? If the answer is Yes, how am I able to differentiate from what you say with such a person unless the information is independently verifiable.
You offer no qualitative details whatsoever. There is no comment on to how many of the joints, and at what locations failed, to start the collapse. You do not give any indication on how much force the floor trusses could take. You do not give any type of calculation to confirm your position that the floor truss joints could not simply snap free (and not pull on the columns) no matter what the force. This seems surprising since you claim the amount of force this collapse will not even be slowed in the least by the remaining structure below. Do you not think the pulverization of concrete would cause a slowing in free fall collapse?
Beyond the argument that your hypothesis is based on belief and not hard science, you also make the claim that it was well known that the towers were vulnerable to global collapse before 9-11. Yet this is not represented in the recorded history prior to 9-11. We do have clear statements by Skilling and Demartini that they did not expect a collapse. These statements should be considered the official historical expectation, unless you can SHOW quotes that refute them (remember these need to be pre 9-11 to establish historical context). You have failed to do this beyond saying that you knew this was not the case. So we are led back to the original problem of unsubstantiated opinion.
Further, since you seem to have high ideals that only experts should discuss the particulars of the collapse, I am interested at what points do you relinquish your expertise and excuse yourself from the conversation. For instance, when we begin to discuss the lower structures resistance to free fall, this becomes much more a question of physics than engineering. So I assume you will put away your hat as an authority at this point.
For those of you who are the apologetic grammar critics, please don't concern yourselves with my feelings on the matter. I certainly feel it is all of you that should be concerned about the embarrassment of stooping to such criticisms. Believe it or not, many of you make typos or real mistakes as well, but I try to concentrate on the ideas being discussed.
aggle-rithm
Ardent Formulist
It is not status that gives the argument weight, it is expertise.
If 100 people with relevant expertise say "A is true" and one person without such expertise says "A is false", I don't care what the social status of these people are. There is a larger group that knows what they're talking about, and I can either spend several years of intensive study learning what they know, or I can accept what they say as fact. The alternative, in your mind, is rejecting the experts out of hand and accepting the non-expert's testimony as fact. Why would anyone do this?
If you want to spend the rest of your life unproductively spinning your wheels, then by all means, question anything and everything you don't understand without trying to learn anything about it.
I haven't done the calculations, but people who are emminently qualified have, and they are satisfied. Why do I believe them? Well, aside from their expertise, they have the advantage of the simple fact that the buildings were observed to collapse, and were filmed from many different angles, and their conclusions are in perfect agreement with observation.
Could be they were wrong, don't you think?
Could it be that when Skilling and Demartini made their claims, they assumed that the fireproofing in the towers had been installed properly, which would have been a mistaken assumption?
Wrong! Anyone can discuss them, but uninformed opinions are not likely to be taken seriously.
Engineers know quite a good deal about physics. It is essential to understanding the forces involved in maintaining a structure's integrity.
Good for you! However, keep in mind that it's difficult to take someone seriously who doesn't take the time to communicate his ideas clearly.
NB, Please learn how the quotes and links work. In this post
http://www.internationalskeptics.com/forums/showthread.php?postid=2271549#post2271549,
I was merely tagging on to Aggle's post to thank Architect for explaining the technical issues of his expert opinion in terms this layman could understand. That's not a common ability. Most experts use jargon (heck, I haven't gotten over FORTRAN enough to spell goto as 2 words), there are few who can explain themselves, without losing their meaning, using ordinary words.
So until you can discern my comment from the message I was quoting (not hard, it says "quote" and has a red arrow to allow you to link back to the post I'm referencing), don't condescend to me. It's not hard to read a thread of only 15 pages. I managed it.
The fact that you'd rather argue philosophy than engineering, architecture, etc., is perhaps understandable, since you say it's your field. But it is also, unfortunately, irrelevant.