POLITICS: Physics Prof Says Explosives, Not Fires Brought Down WTC Towers

BTW....why is it that you want everyone to start reading only after page 54 to page 70?

Could it be because most of the engineers responded to that thread starting at the first page until they got tired of having to repeat themselves over and over and stopped posting, only leaving some people, most of which are the proponents of the "demolition theory," to hang themselves and keep discussing among themselves the topic since they don't want to listen to reason?.... naaa.....

Muaddib : Watching that video it takes approximately 17 seconds from the time we hear the explosion on the video to the collapse of the tower, adding 8.5 seconds to that it puts the explosion at 26.5 seconds before the collapse of the tower.

Wecomeinpeace :
terrorize.dk...
The first pulse is heard at 28 seconds camera time, which means the event occurred at 19.5 seconds WTC time. The collapse of the tower begins at 36 seconds camera time which is the same as WTC time, therefore the event which caused the sound occurred 16.5 seconds before the collapse began. Not 26.5 seconds.

Let me adopt your style of debate for this post, because when I take things seriously your posts really irritate me.

Originally posted by Muaddib
Where in the world do you think that debris would have finally rested when it reached the floor level? (street level).... Do you think it would have opened a 20 floor hole and rested there in a small area for your convinience?.... Or maybe it should all have stayed in one little nice pile.......Now that would be impossible....there was too much debris to have "rested" in one small area....... but as the debris was falling and collapsed against other floors there wasn't enough resistance to stop the falling debris or to deflect most of it, instead it kept falling straight down.

But I thought you said most of the debris didn't land out of the footprint?... And now oh of course it would have landed other places as it couldn't have landed in a nice little stack.... oh well you should have thought of that before you said most of the debris landed inside the footprints, now that you've contradicted yourself again.

Of course when the debris finally settled it rested on a larger area, the floor gave more resistance to the debris hence it didn't open a hole 20 floor hole, or settled in a nice little pile for your convinience....

Only when it settled? ok .... so most of the debris landed in the footprint, but then it "settled" on the other side of the WTC complex.

Originally posted by bsbray11
You can prove that, too.

Really?....

Can you prove to us that the dust cloud seen in the following image is also 80% of the debris from the collapsed building?.... If it is, how is it possible that the buildings where the "dust cloud" reached were not demolished because of the "dust cloud"?......

Can you prove to us that this is all dust?



....from the collapse of a building with redundant structure...

......no wait I'll make it easier for you....

Prove this is dust:



That's what you're saying..... you're saying that is all dust.....

and do tell us bsbray...where do you think the debris would have finally rested when it met the resistance from the bottom floor? (the street level)... Perhaps the debris should have dissapeared into oblivion with the explosives and the squibs that should have been there if it was a controlled demolition huh?....... actually I think you would believe that for some reason.....

and do tell us, muaddib, about that redundant structure... the redundant structured building that was falling down with its weakened redundant structure from some office fires... that it all falls down... i think you'd believe that for some reason.... redundant structure..... do tell us.... what that has to do with what you are responding to. perhabs you contradicted yourself but don't realize it cause you dont know what in the world you are talking about... but just act like you do and are very mocking while doing so... as if you have some authority and weight on the matter that you are mistakenly addressing.

You are saying that the pressure should have gone the same way the pressure started from?....

Yes, do think about it and see if you find the logic on that....

Well, you are saying that by being destroyed downwards, floor by floor, having floors totally destroyed in the redundant structured building, the air in the floors is being pushed down the building as the floors are destroyed.

why yes that makes plenty of sense.

as the floors are destroyed, the air in the floors is pushed downwards as if the building is still airtight. when it is most FREAKING OBVIOUSLY NOT AIRTIGHT.

....redundant structure.

Perhaps you should watch a video of any of the towers collapsing and see that when the large clouds were formed the upper parts of the tower were collapsing on the lower floors....pressure does not go out the same way it starts..... it goes out through the path of least resistance, and the path of least resistance is usually not going against itself.....but out some windows. If the windows and the walls of any of the towers were about 20 feet of solid concrete, the pressure would most probably have gone up, but this was not the case....

oh ok well then since the building had holes all in it and the very collapse was doing nothing but ripping a giant hole in the top of the building gone downwards... giant hole destroying every floor.... of course the air would still go down i mean who would believe that the air would go out in any other direction as pressure began to mount but straight down.

If what you say was true, which is not, then people wouldn't be able to inflate ballons by blowing into them, since according to you, the pressure should escape through the same gaping hole that it came from, in this case the open mouth as they blow air into the ballon.

more like you are trying to inflate a balloon by shooting holes in it and expecting the air not to leak.

the wtc towers were not airtight, genius. they were freaking being torn down floor by floor. air could've escaped through the topmost remaining floor at any moment .... there was absolutely nothing to keep the air from escaping through the tops of the buildings.... and you don't understand how the floors were laid out at all... the air would've had to shot across a floor without decompressing to blow out a specific area of window. do you know what means? any idea? i don't think you do or you wouldn't be making such an ignorant argument. redundant structure......

You are kidding right?.... If there were any explosives, they would have been heard for miles before any of the towers started collapsing yet no such loud explosions were heard....what was heard was the mass of falling debris as the debris and steel beams fell and were twisted by the weight....which of course made a loud sound.... or do you think that the sound should have dissapeared and instead people should have heard birds singing?......

are you kidding? theres a video here now with video taken far away and you can hear explosions.... then once the collapse started it was a lot of explosions going off so closely to each other that you couldnt make out one from another... how are you going to hear specific explosions in that? give up? you can't.

a fireman said he heard 'bam bam bam bam' coming down the building like it was being blown out floor by floor. why doesnt that count? because oh yeah it was loud because of the debris falling so yeah it was loud but how come people didnt hear it right? that makes plenty of sense, muaddib.

Originally posted by bsbray11
If 9/11 was a conspiracy, you wouldn't believe it, would you? With the same circumstances, I mean: NIST coming out with these reports, etc. Would you buy into it? Or do you think you'd give it a fair hearing and realize something was up? Eh?

Would i believe 80% of the debris from the collapsing tower should have rested in a small space or somehow opened a 20 floor hole to finally rest there, and that most of the squibs and the loud explosions from controlled demolition charges dissapeared into oblivion if NIST or FEMA put it in their report?.... no....

well would i believe that when the redundant structure failed from fire weakening it and jet damage that it should make the whole building fall straight down and not like it should have if it were hit by a jet and then fire weakened the redundant structure which would be where the tower could fall in the direction of least resistance which would contradict it falling straight down into itself because thats where the most resistance absolutely possible was? and what about that 80% debris figure i dont think you understand wtf i was even getting at with that one i mean you take it as if it means it was a demo but it doesnt.... but it does mean that the mass driving the collapse was very crappy at best and yet the collapse kept going without slowing down... do i believe that was supposed to happen? no. do you?

LaBTop, you think that quoting wcip makes him right and my statement wrong?.....

Look at that video again.... The "supposed" explosion occurs when the clock is at 17-16 seconds.....the clock reaches 0 when the tower starts collapsing....

By the time you hear the sound of the explosion in that video 8.5 seconds would already have gone by because of that's the amount of time that the sound would take to have reached the other side of the pier, where the camera was at recording.

17+8.5= 25.5 seconds or 16+8.5= 24.5 seconds

Yes, i guess you are right i made a mistake when saying it was 26.5 seconds... the time between the supposed explosion and the time the tower collapses should be 25.5 to 24.5, but not what wcip proclaims it should be.



[edit on 25-11-2005 by Muaddib]

Nice finds with the videos, LaBTop/WCIP. I haven't had enough time to go through and look at them and all that's been posted about them, but it's an awesome find to even have a video of white smoke coming out of the base of a tower before collapse there, let alone recordings of explosions.

Originally posted by HowardRoark

Originally posted by Hunting Veritas
WCIP, how are you sure that sound isn't faked?

or from another direction entirely?

Was something else exploding in NYC at the exact same time a tower was beginning to collapse?

How come this was only heard 1.5 miles away, and not by the tens of thousands of people closer?

People on the ground, being caught up in the horror of it all, and not having such a great view of the tops of the buildings, are probably not going to find anything unusual about hearing massive explosions before the buildings start to collapse. Especially on retrospect, after the much more stunning events of the collapses themselves, are such explosions not going to stick out in the mind. They would just be remembered as parts of the collapses, along with all the rest of the loud, metallic roars, if remembered at all.

Here you have a sound recording, letting you know exactly what was heard, assuming it's authentic, and it does appear to be authentic. I think the sound recording is much more reliable.

[edit on 25-11-2005 by bsbray11]

Originally posted by bsbray11

But I thought you said most of the debris didn't land out of the footprint?... And now oh of course it would have landed other places as it couldn't have landed in a nice little stack.... oh well you should have thought of that before you said most of the debris landed inside the footprints, now that you've contradicted yourself again.

As i have said several times in the past....read what i posted instead of inventing and trying to reword what i said so it can fit your theory....

I said most of the debris fell on the rest of the floors of the towers, not that most of the debris rested in one little pile......

So before you go along changing what people said trying to support your dellusion, check and make sure you understand what they actually said......before you keep making a fool of yourself.

Originally posted by bsbray11
Can you prove to us that this is all dust?

i am confused now.... Never mind "the exact amount of dust" in there......but wasn't one of the main topics of the "controlled demolition theory" that most if not all of the concrete was turned to dust?...... Now you are saying that's not dust...what is it then... larger pieces of concrete?........

Originally posted by bsbray11
and do tell us, muaddib, about that redundant structure...

Since you don't know what redundant structure means and what it has to do with what we are discussing, here is a link....

STRUCTURAL PERFORMANCE OF REDUNDANT STRUCTURES UNDER LOCAL FIRES

If you still don't understand what that link means. The redundancy, or the redundant structure in a building allows for the building to shift it's load towards other columns if a couple of columns are lost. But when too many columns buckle, the redundancy, or the redundant structure of the building, or the floor fails, hence the building, or floor, collapses, partially or totally....

Originally posted by bsbray11
the redundant structured building that was falling down with its weakened redundant structure from some office fires...

I see....so we are going back to the phrase that the "demolition theorist....folk keep bringing up..... "some office fires" Like that phrase is going to diminish the extend of fires produced from several thousand gallons of jet fuel......plus every other flammable material found in the towers.....

Nice try bs.....

Originally posted by bsbray11
Well, you are saying that by being destroyed downwards, floor by floor, having floors totally destroyed in the redundant structured building, the air in the floors is being pushed down the building as the floors are destroyed.

why yes that makes plenty of sense.

as the floors are destroyed, the air in the floors is pushed downwards as if the building is still airtight. when it is most FREAKING OBVIOUSLY NOT AIRTIGHT.

First of all, you are forgetting a few facts, which i did not explain completly but perhaps it was because i thought maybe, just maybe you would have known at least this much about the wtc.... or about any modern skyscraper...

Silly me....for making that mistake... i forgot who i was responding to....

Most of the support beams used in the construction of the wtc were in the outside, while the inside of the towers, were mostly air and had fewer support beams....hence the name of the structural model used for the construction of the wtc being called rigid hollow tube......

You can find a description of it here...
www.civil.usyd.edu.au...

What does this have anything to do with what we are discussing?..... Simpy because any collapse in the buildings would have started from the inside...and not the outside.....since the inside of the structures were weaker than the outside.........add the clouds of dust and smoke which further obscured the view of much of what was happening....and then perhaps your mind can unravel the truth of what was most likely to have happened when the towers began collapsing, and what happened to that air as it was being pushed down from floor to floor.

Did "all the air get pushed down" from floor to floor? probably not....that's why we see some air pufs coming out from some windows, which were probably cracked since I believe the windows were supposed to be shatter resistant, but I could be wrong.



[edit on 25-11-2005 by Muaddib]

Originally posted by Muaddib
BTW....why is it that you want everyone to start reading only after page 54 to page 70?

Could it be because most of the engineers responded to that thread starting at the first page until they got tired of having to repeat themselves over and over and stopped posting, only leaving some people, most of which are the proponents of the "demolition theory," to hang themselves and keep discussing among themselves the topic since they don't want to listen to reason?.... naaa.....

You, Muaddib, are a cross-grained fellow. With an attitude problem as big as a cauliflower.

If you really had taken my advice, you would have crossed (oops) the path of the 11th poster on page 54. I will serve you some quotes of this engineer :

I'm an engineer. Mechanical electrical instead of civil but did some structural analysis of bridges & buildings. This is beyond civil structural though since it heavily relies upon unique chemistry. Beyond only physics but rather multidisciplines.

As such, I browsed this thread. After reading a few pages past page 10, I noticed enormous errors, so I quit there. Good math, good science but non-trivial errors.

The colorful ad hominems were every entertaining. At least there was no censoring. That is more important than a little mud slinging. Because censorship drives away expertise while mud slinging is just a nuisance.

Engineering problem?? Yes. An engineer would not post 40 pages of point and rebuttal continuing the same non-trivial errors. As such, little point to reading from approx page 10 onward. Truth is, neither side of the argument caught these errors for 40 pages. ....etcetera.

That's the reason. And after reading to the last page, nobody stops you to have a look at the first 53 pages ofcourse.

Now let's address your calculation skills again (get a bit tired of it) :

Originally posted by Muaddib
LaBTop, you think that quoting wcip makes him right and my statement wrong?.....

Look at that video again.... The "supposed" explosion occurs when the clock is at 17-16 seconds.....the clock reaches 0 when the tower starts collapsing....

By the time you hear the sound of the explosion in that video 8.5 seconds would already have gone by because of that's the amount of time that the sound would take to have reached the other side of the pier, where the camera was at recording.

17+8.5= 25.5 seconds or 16+8.5= 24.5 seconds

Yes, i guess you are right i made a mistake when saying it was 26.5 seconds... the time between the supposed explosion and the time the tower collapses should be 25.5 to 24.5, but not what wcip proclaims it should be.
[edit on 25-11-2005 by Muaddib]

Are you blind? The seconds timer of my Media Player video player reaches 28 seconds when you HEAR that explosion.
It reaches 36 seconds when the tower starts collapsing, which is a visual event in REAL time, let's call that EYE-time.
The difference between SEEING and HEARING is 8.5 seconds. You HEAR it 8.5 seconds later !
That means if you had SEEN the explosion, it would have been 8.5 seconds earlier in the video, thus at the 28 -8.5 = 19.5 seconds point.
And not your fabulous 25.5 to 24.5 seconds !

Where on earth you pull that "clock at 17-16 seconds" from, is a mystery to me, alike as that "clock reaches 0" remark of yours.

Appologies PLEASE ! For both insults of my intelligence.

This reaches gross proportions.
Where did you get your education?
I will not address all the blablabla before these remarks, that's obviously lost time.

Most of the support beams used in the construction of the wtc were in the outside, while the inside of the towers, were mostly air and had fewer support beams....hence the name of the structural model used for the construction of the wtc being called rigid hollow tube......

The WTC towers were constructed around the most rigid, strong internal central core construction on earth at that time, and were seen as most innovative by every structural engineer.
Bsbray has posted numerous pictures of the construction phases of the towers, where you could see how strong those 47 center core collumns were, and how thick.
Hollow tube, are you delusional?

And then this :

Simply because any collapse in the buildings would have started from the inside...and not the outside.....since the inside of the structures were weaker than the outside....

Now I really start wondering if you are pre-college material.
I will not even start addressing that "air pushed down" theory of yours, I leave that to Bsbray so he can have some fun too.

No wonder 51 % of americans voted for George W Putsch.
If it's all this kind of material, no wonder.

Originally posted by LaBTop
This reaches gross proportions.
Where did you get your education?
I will not address all the blablabla before these remarks, that's obviously lost time.

Most of the support beams used in the construction of the wtc were in the outside, while the inside of the towers, were mostly air and had fewer support beams....hence the name of the structural model used for the construction of the wtc being called rigid hollow tube......

The WTC towers were constructed around the most rigid, strong internal central core construction on earth at that time, and were seen as most innovative by every structural engineer.
Bsbray has posted numerous pictures of the construction phases of the towers, where you could see how strong those 47 center core collumns were, and how thick.
Hollow tube, are you delusional?

And then this :

Simply because any collapse in the buildings would have started from the inside...and not the outside.....since the inside of the structures were weaker than the outside....

Now I really start wondering if you are pre-college material.
I will not even start addressing that "air pushed down" theory of yours, I leave that to Bsbray so he can have some fun too.

No wonder 51 % of americans voted for George W Putsch.
If it's all this kind of material, no wonder.

Actually your ignorant rant was quite foolish and incomplete. You need to check your facts, you don't need to insult, and presenting well founded counter-ideas are always good in an well presented arguement...and, of course, try not to finish with an unecessary political statement...

To solve the problem of wind sway or vibration in the construction of the towers, chief engineer Leslie Robertson took a then unusual approach, instead of bracing the buildings corner-to-corner or using internal walls, the towers were essentially hollow steel tubes. Each tower thus contained 240 vertical steel columns called Vierendeel trusses around the outside of the building which were bound to each other using ordinary steel trusses. In addition, 10,000 dampers were included in the structure. With a strong shell such as this, the internal floors could be simply light steel and concrete with internal walls not needed for structural integrity, creating a tower that was extremely light for its size. This method of construction also meant that the twin towers had the world's highest load-bearing walls. The exterior steel supports were spaced 22 inches (559 mm) apart, and narrow windows filled the gaps in between.

So next time my friend... do a little research... then have a discussion.

There is no need for any abusive ad-hominems.

Originally posted by LaBTop
This reaches gross proportions.
Where did you get your education?
I will not address all the blablabla before these remarks, that's obviously lost time.

Were you saying something about blablablabla?.....

Let's address your main point in this thread, since some of the points in the earlier thread will take a bit more time, and in about 15 minutes i got to get ready to have some fun, perhaps you should try that....

Originally posted by LaBTop
The WTC towers were constructed around the most rigid, strong internal central core construction on earth at that time, and were seen as most innovative by every structural engineer.
Bsbray has posted numerous pictures of the construction phases of the towers, where you could see how strong those 47 center core collumns were, and how thick.
Hollow tube, are you delusional?

I gave you a direct link to the Department of Civil engineering of the University of Sidney....... where they post some of the engineering aspects of the wtc........

You should have read that link first, instead of blowing smoke and making more of a fool of yourself......

But, what can I say, you digged your own grave.

Here are some excerpts from that site.

The Structural System


Yamasaki and engineers John Skilling and Les Robertson worked closely, and the relationship between the towers' design and structure is clear. Faced with the difficulties of building to unprecedented heights, the engineers employed an innovative structural model: a rigid "hollow tube" of closely spaced steel columns with floor trusses extending across to a central core. The columns, finished with a silver-colored aluminum alloy, were 18 3/4" wide and set only 22" apart, making the towers appear from afar to have no windows at all.

Let's read some more from that site....

The structural system, deriving from the I.B.M. Building in Seattle, is impressively simple. The 208-foot wide facade is, in effect, a prefabricated steel lattice, with columns on 39-inch centers acting as wind bracing to resist all overturning forces; the central core takes only the gravity loads of the building. A very light, economical structure results by keeping the wind bracing in the most efficient place, the outside surface of the building, thus not transferring the forces through the floor membrane to the core, as in most curtain-wall structures. Office spaces will have no interior columns. In the upper floors there is as much as 40,000 square feet of office space per floor. The floor construction is of prefabricated trussed steel, only 33 inches in depth, that spans the full 60 feet to the core, and also acts as a diaphragm to stiffen the outside wall against lateral buckling forces from wind-load pressures."

Excerpted from.
www.civil.usyd.edu.au...

Enjoy.....


[edit on 25-11-2005 by Muaddib]

Originally posted by LaBTop
I will not even start addressing that "air pushed down" theory of yours, I leave that to Bsbray so he can have some fun too.

I've about given up on that, I think.

According to Muaddib, even though the towers were being destroyed floor by floor, concrete dust ejecting from the pulverized concrete slabs between floors, and steel beams being hurled around like leaves in the wind, the towers were somehow airtight and could retain an air pressure that has no way of accumulating in the first place.

How do you argue with that? The problems with it are so obvious that it can hardly be broken down anymore. Science is definitely not a strong point of mine, but Jesus. The towers were simply not airtight and there was no way the pressure could accumulate, let alone is there no logic being suggesting the air flew undecompressing across half a WTC floor to bust out a window, spewing concrete dust and all. It's not more complicated than that; that's all there is to it, plain and simple.

So I'll just have some fun now (), instead of trying to explain anything to someone who obviously does not really care how much sense he makes.

Originally posted by Muaddib
As i have said several times in the past....read what i posted instead of inventing and trying to reword what i said so it can fit your theory....

I said most of the debris fell on the rest of the floors of the towers, not that most of the debris rested in one little pile......

So before you go along changing what people said trying to support your dellusion, check and make sure you understand what they actually said......before you keep making a fool of yourself.

Muaddib, why don't you post some kind of source to back up your assumption that most of the debris fell on the floors below? That's the way you're supposed to go about it. Not just making stuff up and assuming it's true just because you said it and that's what you think.

Now why don't you stop trying to reword what you said... because you said the debris fell on the floors... not the 80% that fell outside of the footprint.. which contradicts what you just said about most of the debris falling on the floors which the rest of the most of it fell directly onto the redundant structure. Then it contradicts too what you said about most of the debris falling within the footprint until it was deflected by the redundant structure at which point the majority of the 80% of it that fell outside of the footprint was not really outside of the footprint before it was deflected by the footprint, but it was ejected outside of the footprint and was never deflected by anything.

i am confused now.... Never mind "the exact amount of dust" in there......but wasn't one of the main topics of the "controlled demolition theory" that most if not all of the concrete was turned to dust?...... Now you are saying that's not dust...what is it then... larger pieces of concrete?........

I noted that some 80% or so of the debris landed outside of the footprints and showed pics, and you made some remark or other about it being concrete that was ejected. It wasn't just concrete. It was 80% of the total debris, steel and concrete and all, and as you can see in pics from Ground Zero, there was steel everywhere, least of all in the footprints but all over the WTC complex in general and beyond. Unless you think those little shards of material flying through the air, ejected from their original positions, are cleverly disguised dust.

Since you don't know what redundant structure means and what it has to do with what we are discussing, here is a link....

STRUCTURAL PERFORMANCE OF REDUNDANT STRUCTURES UNDER LOCAL FIRES

If you still don't understand what that link means. The redundancy, or the redundant structure in a building allows for the building to shift it's load towards other columns if a couple of columns are lost. But when too many columns buckle, the redundancy, or the redundant structure of the building, or the floor fails, hence the building, or floor, collapses, partially or totally....

No: let me tell you what structural redundancy is:

It's a term you throw around a lot in your sentences to make it sound like you know what you're talking about, when really it was totally unnecessary to mention in the first place.

I see....so we are going back to the phrase that the "demolition theorist....folk keep bringing up..... "some office fires" Like that phrase is going to diminish the extend of fires produced from several thousand gallons of jet fuel......plus every other flammable material found in the towers.....

Nice try bs.....

The jet fuel burned up within 15 minutes or so of the fires... hence the downsizing and discoloration of the smoke coming from either building from lighter shades to darker shades, which is indicative of soot in the smoke, from uncombusted hydrocarbons. So that a trend started after 15 minutes +/- of the impacts of the smoke beginning to contain uncombusted hydrocarbons as the overall quantity of smoke diminished from the initial quantities from the fire deriving fuel from the jet fuel indicates that something happened in the buildings, such as a change of primary fuel sources, to cause the intensity of the fires to diminish.

First of all, you are forgetting a few facts, which i did not explain completly but perhaps it was because i thought maybe, just maybe you would have known at least this much about the wtc.... or about any modern skyscraper...

Silly me....for making that mistake... i forgot who i was responding to....

Awww, I love you too.

Most of the support beams used in the construction of the wtc were in the outside,

If you mean the perimeter columns outnumbering the core columns, you're right. But the core columns were just as responsible for holding the buildings up as the perimeter columns. Within the core columns the buildings would not have been able to stand at all, and there were some number of them within the buildings.

Here's the WTC as it was being constructed:



See all those columns around the middle?

while the inside of the towers, were mostly air and had fewer support beams....

Mostly air, sure, just like your house is mostly air just because most of the space inside of it was designed to be empty so you could live in it. Doesn't mean there are "fewer" support columns within the building, which is only true by number and not by importance or size or strength: the core columns were much bigger and just as important as the outer columns. If I'm not mistaken they were designed to carry 50% of the load while the outer columns carried the other 50%.

hence the name of the structural model used for the construction of the wtc being called rigid hollow tube......

Wait - but what about my mother? Is she a hollow tube now?

What does this have anything to do with what we are discussing?..... Simpy because any collapse in the buildings would have started from the inside...and not the outside.....since the inside of the structures were weaker than the outside.........

Wrong.

add the clouds of dust and smoke which further obscured the view of much of what was happening....and then perhaps your mind can unravel the truth of what was most likely to have happened when the towers began collapsing, and what happened to that air as it was being pushed down from floor to floor.

Oh, I'm sure there were squibs popping out from each floor for a good ways down. But it wasn't from air. But if there wasn't all that dust conveniently in the way, yeah: that's what you'd see.

Originally posted by bsbray11
Science is definitely not a strong point of mine, but Jesus.

...

Muaddib, why don't you post some kind of source to back up your assumption that most of the debris fell on the floors below? That's the way you're supposed to go about it. Not just making stuff up and assuming it's true just because you said it and that's what you think.

First I am going to assume you didn't read his post prior because he clearly posted a source.

Second, his source and other reliable sources as well as my post, clearly states how the internal floors could have fell on top of each other if there is no real internal structural integurity.

Gosh, I would sure hate to use that ignore button...

Originally posted by rmatrem
First I am going to assume you didn't read his post prior because he clearly posted a source.

Not for what I was addressing, he didn't. A source for one statement is not a source for them all.

Second, his source and other reliable sources as well as my post, clearly states how the internal floors could have fell on top of each other if there is no real internal structural integurity.

Yeah, if there were no core columns supporting half of the buildings' weight loads. Too bad there were.

And I think it was FEMA (could be mistaken) that approximated maybe two core columns were knocked out by the impacts by the engines, if they had flown off in the right directions, as the thin aluminum and titanium that composed most of the rest of the jets wouldn't have been enough after withstanding the initial impacts. And there would have been too poor of ventilation internally, going by the setup of the air shafts, to support much of a fire much off from the perimeter columns. So in all likelihood, besides existing in the first place (which is elementary enough to fail to consider), the core columns weren't in too bad of shape, either.

Gosh, I would sure hate to use that ignore button...

Ignore me and save us both some trouble. I like how you threaten me with that as if I'm supposed to give two turds.

[edit on 25-11-2005 by bsbray11]

What are you quoting me like I need to be debunked!

How about quoting a source...

And clearly science and engineering aren't your "strong point".

No point in continuing an empty discussion...

the central core takes only the gravity loads of the building

hello? mcflies?

you know what else is great about that video from across the river, is you can see some of the core still standing after the rest of the building has been demolished, before it begins to TIP, and then falls straight down. you can even see a flash of light through the smoke that initiates this last part of the collapse.

what pancaked that remaining part of the core? crushing amounts of syrup theory?

Sometimes i wonder if any of you know what you are talking about.

I also remember reading a few threads on wtc collapse earlier where people were saying there was no real support from the external structure. It was only the columns in the center of the building.
I think that was argued pretty strongly by someone.
I might have a look back and see if i can find any quotes.

OK, let's can the attitude. This is the News Forum, decorum.

The 9/11 Research Site goes into a lot of detail about the construction of the WTC Towers, which it gathers from various sources, including pre-9/11 sources:

1 and 2 World Trade Center used the so-called tube within a tube architecture, in which closely-spaced external columns form the building's perimeter walls, and a dense bundle of columns forms its core. Tall buildings have to resist primarily two kinds of forces: lateral loading (horizontal force) due mainly to the wind, and gravity loading (downward force) due to the building's weight. The tube within a tube design uses a specially reinforced perimeter wall to resist all lateral loading and some of the gravity loading, and a heavily reinforced central core to resist the bulk of the gravity loading. The floors and hat truss completed the structure, spanning the ring of space between the perimeter wall and the core, and transmitting lateral forces between those structures.

A diagram showing the arrangment of support columns within the WTC:




More on the core structure:

Each tower was supported by a structural core extending from its bedrock foundation to its roof. The cores were rectangular pillars with numerous large columns and girders, measuring 87 feet by 133 feet. The core structures housed the elevators, stairs, and other services. The cores had their own flooring systems, which were structurally independent of the floor diaphragms that spanned the space between the cores and the perimeter walls. The core structures, like the perimeter wall structures, were 100 percent steel-framed.

A diagram giving a rough depiction of the setup of core columns:



The line segment is the path of the jet that impacted WTC2, giving an idea as to how many core columns that jet knocked out.





That last pic of those two core columns was taken from Ground Zero after the collapses.

And the perimeter columns:

The towers' perimeter walls comprised dense grids of vertical steel columns and horizontal spandrel plates. These, along with the core structures, supported the towers. It is controversial whether the perimeter columns were expected to bear much of the towers' weight, in addition to their role in stiffening the structures against lateral loads. Regardless, it is clear that the core structures were designed to support several times the weight of each tower by themselves.

The towers required the strength of both the perimeter columns and core columns to stand, and both contributed to the structural integrity of the buildings. A minority of either were knocked out during either impact. FEMA itself details neither tower exceeding 13% perimeter column failure in the regions of the impacts, and neither did the core columns suffer much damage in all likelihood, and certainly not enough to cause any collapse.

So for someone who knows very little about engineering and physics, the buildings are contructed to resist two different forces.
We have lateral loading (horizontal force), for example wind, and gravity loading (downward force).
The exterior walls? columns? supports? whatever you call them, are there mainly to resist lateral loads
The interior columns to resist gravity loads.

If we are lookng at the collapse due to gravity, its the central columns that are important.

Is that correct, anyone disagree?

Originally posted by AdamJ
So for someone who knows very little about engineering and physics, the buildings are contructed to resist two different forces.
We have lateral loading (horizontal force), for example wind, and gravity loading (downward force).
The exterior walls? columns? supports? whatever you call them, are there mainly to resist lateral loads
The interior columns to resist gravity loads.

If we are lookng at the collapse due to gravity, its the central columns that are important.

Is that correct, anyone disagree?

Well if we aren't going to distinguish between "live" loads and "dead loads" it is pretty close. In addition, the exterior and the core columns pretty much split the gravity loads 50/50.

One other thing to keep in mind, reisitance to lateral forces was not built into the infividual exterior columns, but rather in the overall design of the latice and squared tube. Once the collapse started, that resistance would no longer be there and both the interior and exterior columns would be subject to the buckling forces imparted by the falling mass.

THAT is a key concept to understand..