How the WTC Core Supports Weakened.

[SBrown]

The WTC towers had 47 cores that ran vertical the length of the building. How did these vertical supports fail all along the length of the building? I could see failure if they were horizontal, but vertical columns would hold under any plausible crushing scenario. I do not see a pancake or falling weight snapping all these core columns over and over again on the way down. This just does not make sense.

[Gravy]

The WTC towers had 47 cores that ran vertical the length of the building. How did these vertical supports fail all along the length of the building? I could see failure if they were horizontal, but vertical columns would hold under any plausible crushing scenario. I do not see a pancake or falling weight snapping all these core columns over and over again on the way down. This just does not make sense.
Why does that not make sense? Are you thinking that only vertical forces were acting on the columns?

[SBrown]

Why does that not make sense? Are you thinking that only vertical forces were acting on the columns?
Where did the horizontal forces come from?

[Diogenes]

.... but vertical columns would hold under any plausible crushing scenario.

They would ?

Your source for this conclusion ?

[R.Mackey]

Buckling:

"As the joists on one or two of the most heavily burned floors gave way and the outer box columns began to bow outward, the floors above them also fell." Eagar paper in JOM (http://www.tms.org/pubs/journals/JOM/0112/Eagar/Eagar-0112.html)

We've been over this.

Also, as anybody who's ever studied statics or structural mechanics knows, if you load a column too much it will bow, and create opposing lateral forces inside the column. QED.

[SBrown]

They would ?

Your source for this conclusion ?


So they snapped then?

What about every 10-15 feet?

[SBrown]

Buckling:

"As the joists on one or two of the most heavily burned floors gave way and the outer box columns began to bow outward, the floors above them also fell." Eagar paper in JOM (http://www.tms.org/pubs/journals/JOM/0112/Eagar/Eagar-0112.html)

We've been over this.

Also, as anybody who's ever studied statics or structural mechanics knows, if you load a column too much it will bow, and create opposing lateral forces inside the column. QED.


Do you just ignore the existance of core columns or are you just not educated on this subject?

[R.Mackey]

Funny, I was thinking of asking you the same thing, but decided not be so rude.

The outer box columns bowing outward means the load sags, and pushes outward on the box columns. If there is no collapse, e.g. static analysis holds, Newton's 3rd law applies -- this outward push is balanced by an inward push on the interior columns.

Even without the buckling, a gross overload will cause vertical columns to enter a bending mode and probably snap in the middle.

I would hazard a guess that I am far more educated on the subject than you are, but I am perfectly willing to explain. Are you willing to learn?

[SBrown]

Funny, I was thinking of asking you the same thing, but decided not be so rude.

The outer box columns bowing outward means the load sags, and pushes outward on the box columns. Newton's 2nd law applies -- this outward push is balanced by an inward push on the interior columns.

Even without the buckling, a gross overload will cause vertical columns to enter a bending mode and probably snap in the middle.

I would hazard a guess that I am far more educated on the subject than you are, but I am perfectly willing to explain. Are you willing to learn?


So this "bowing" and pushing, pulling and "probably" snapping happened all at once or a few floors at a time?

http://homepage.mac.com/dansound/.Public/Pix/SteelOnFire/WTC_Core_03.jpg

[R.Mackey]

I don't understand your question. Clearly the collapse was sequential in nature, although if you put that much runaway force into a structure, the load will become critical very, very quickly. Once we can no longer treat the problem statically, it becomes difficult to say whether the failure is one floor at a time (in rapid, uninterrupted succession) or whether it spans a larger area.

The question is also academic at that point.

[coalesce]

The WTC towers had 47 cores that ran vertical the length of the building. How did these vertical supports fail all along the length of the building? I could see failure if they were horizontal, but vertical columns would hold under any plausible crushing scenario. I do not see a pancake or falling weight snapping all these core columns over and over again on the way down. This just does not make sense.

No, what doesn't make sense is Chewbacca living on the planet Endor with the Ewoks. That does not make sense. I mean, he's a 7-foot tall Wookie living with 3-foot tall Ewoks. Ladies and gentlemen of this supposed jury, THAT DOES NOT MAKE SENSE!

J. Cochran

[Gravy]

SBrown, it's great to come here with legitimate questions and issues that you would like to discuss. But that's not what you do. Every time you've started a thread, you've done so with a huge chip on your shoulder. You back your statements with opinions, and when those are countered with facts, you become snippy and insulting.

Why are you doing this?

[SBrown]

SBrown, it's great to come here with legitimate questions and issues that you would like to discuss. But that's not what you do. Every time you've started a thread, you've done so with a huge chip on your shoulder. You back your statements with opinions, and when those are countered with facts, you become snippy and insulting.

Why are you doing this?

Are you talking to coalesce or me?:confused:

[SBrown]

No, what doesn't make sense is Chewbacca living on the planet Endor with the Ewoks. That does not make sense. I mean, he's a 7-foot tall Wookie living with 3-foot tall Ewoks. Ladies and gentlemen of this supposed jury, THAT DOES NOT MAKE SENSE!

J. Cochran

So you are a Star Wars fan....super, you are also a idiot...super.

[Gravy]

Are you talking to coalesce or me?:confused:
As my reply was addressed to you, and as you did what I'm talking about juat a few posts ago, yes, SBrown, I was talking to you. I've asked you to do this before, but you don't seem to get it: please re-read your posts and try to imagine how they sound to others.

[SBrown]

As my reply was addressed to you, and as you did what I'm talking about juat a few posts ago, yes, SBrown, I was talking to you. I've asked you to do this before, but you don't seem to get it: please re-read your posts and try to imagine how they sound to others.

My question to you still stands and is the only reply that was not to a snide remark from addon.

[Gravy]

My question to you still stands and is the only reply that was not to a snide remark from addon.
I have no idea what that sentence means.

[SBrown]

I have no idea what that sentence means.

I am thinking you have decided to not understand.

[R.Mackey]

SBrown, take it to PM. I'm leaving this discussion as your conduct leaves much to be desired.

The reason the collapse doesn't make sense to you, as you indicated in your first post, is because you are inexperienced in the subject. http://en.wikipedia.org/wiki/Solid_mechanics has a reasonable reference listing at the bottom -- this will give you sufficient grounding in the underlying physics, if you are willing to learn. If possible, I would also reccommend you ask an educator in your area, as the fundamentals can be explained by any engineering teacher at any level. I would, however, advise you to seek consultation with an open mind.

Arrogance cannot teach.

[Gravy]

I am thinking you have decided to not understand.
No, I don't understand because your writing is unclear. I've also asked this before of you: do you have anything positive to add here? If so, proceed.

[SBrown]

So I am not following the proper protocols here?

My second post on this thread was a question to you Gravy.

Why do I need to take this to pm?

[gumboot]

SBrown... are you related to C.Brown?

-Andrew

[Mercutio]

So they snapped then?

What about every 10-15 feet?
In the Ground Zero Museum, there will be beams and columns exhibited, recovered from the site. Currently, they are being stored. Here you can listen (http://www.npr.org/templates/story/story.php?storyId=5484916) to an NPR story on it. Note that they speak of 30 to 50 foot segments. These will eventually be on display for you to visit if you like; I doubt very much that they are lying here.

The link also shows "the compression"; a chunk of material that was originally 4 stories of the building, compressed into about 4 feet. Just to give you some idea of the sheer amount of force available to bend the colums and beams.

[SBrown]

SBrown... are you related to C.Brown?

-Andrew
I don't know what you are talking about. Is this anouther JREF attempt at ridicule? I am not up on the humor here.

[coalesce]

So you are a Star Wars fan....super, you are also a idiot...super.

Actually, I was aiming for "dumbass," but "idiot" will do.

You will forgive me, however, if I choose not to engage in name-calling.

Michael

[Pyrrho]

http://www.tms.org/pubs/journals/JOM/0112/Eagar/Eagar-0112.html


Nearly every large building has a redundant design that allows for loss of one primary structural member, such as a column. However, when multiple members fail, the shifting loads eventually overstress the adjacent members and the collapse occurs like a row of dominoes falling down.

The perimeter tube design of the WTC was highly redundant. It survived the loss of several exterior columns due to aircraft impact, but the ensuing fire led to other steel failures. Many structural engineers believe that the weak points—the limiting factors on design allowables—were the angle clips that held the floor joists between the columns on the perimeter wall and the core structure (see Figure 5). With a 700 Pa floor design allowable, each floor should have been able to support approximately 1,300 t beyond its own weight. The total weight of each tower was about 500,000 t.

As the joists on one or two of the most heavily burned floors gave way and the outer box columns began to bow outward, the floors above them also fell. The floor below (with its 1,300 t design capacity) could not support the roughly 45,000 t of ten floors (or more) above crashing down on these angle clips. This started the domino effect that caused the buildings to collapse within ten seconds, hitting bottom with an estimated speed of 200 km per hour. If it had been free fall, with no restraint, the collapse would have only taken eight seconds and would have impacted at 300 km/h.1 It has been suggested that it was fortunate that the WTC did not tip over onto other buildings surrounding the area. There are several points that should be made. First, the building is not solid; it is 95 percent air and, hence, can implode onto itself. Second, there is no lateral load, even the impact of a speeding aircraft, which is sufficient to move the center of gravity one hundred feet to the side such that it is not within the base footprint of the structure. Third, given the near free-fall collapse, there was insufficient time for portions to attain significant lateral velocity. To summarize all of these points, a 500,000 t structure has too much inertia to fall in any direction other than nearly straight down.


Article is a bit old--I think the "angle clips" hypothesis has been revised since this one was published.

It's difficult enough to keep structural steel aligned during construction, let alone after a huge portion of the finished building collapses. They don't just bold and weld girders together and have it all work. There is a lot of effort involved in keeping the structure from warping because of temperature changes, wind, etc. during construction. Once the collapse started the tremendous forces just ripped everything apart--as one might expect.

[Gravy]

So I am not following the proper protocols here?

My second post on this thread was a question to you Gravy.

Why do I need to take this to pm?
And others answered your question before I got to it. That happens a lot on forums. If I disagreed with their answers, I would say so.

I didn't say you need to take this to PM. I asked you to re-read your posts and try to imagine how they sound to others.

[kevin]

So you are a Star Wars fan....super, you are also a idiot...super.

No, they're a South Park fan. If you can't get your pop culture right, how can we trust your conclusions about the WTC?

[coalesce]

No, they're a South Park fan. If you can't get your pop culture right, how can we trust your conclusions about the WTC?

A true Litmus test, Grasshopper.

Thank you.

Michael

[SBrown]

No, they're a South Park fan. If you can't get your pop culture right, how can we trust your conclusions about the WTC?

Is this some sort of JREF humor?

[kevin]

Is this some sort of JREF humor?

gah, nothing takes away the funnly like having to explain something.
http://en.wikipedia.org/wiki/Chewbacca_defense

[twinstead]

Is this some sort of JREF humor?


I suspect it's some sort of time passing technique while waiting for real evidence and objective investigation.

Just a thought...

[SBrown]

gah, nothing takes away the funnly like having to explain something.
http://en.wikipedia.org/wiki/Chewbacca_defense


So people here are expected here to know every detail of a cartoon called South Park? I have never seen it.

[rwguinn]

So people here are expected here to know every detail of a cartoon called South Park? I have never seen it.
I have, and it is funny and has nothing to do with buckling and columns..
SBrown, if you are seriously asking, I propose an experiment for you.
Go get a length of spaghetti--uncooked, please. you will notice that it is very strong if you try to push both ends lengthwise--in compression. IF you hold it in the middle, with one end on the table, uou can put something very heavy on the other end, and it will not break. Now, remove your grip from the middle, and watch it break into a large number of pieces.
How much weight a column will support is a function of its slenderness ratio, that is, its total length compared to its cross-sectional geometric moment-of-inertia and area.
So, with 6 pieces of 2inch length spaghetti set verticaly, you could support say, the first 2 volumes on the Encyclopedia Britannica. Make those lengths 4 inches, and things get wobbly. 6 inches, and you have little bitty pieces of spaghetti again.
That is exactly what happened when several floors got taken out--the 2" chunks are now suddenly 6 inches long-the hand was removed.
The floors, you see, made the columns keep their relationship to each other. They were the hand in the middle of the stick. When that went away. they snapped-broke, bent and everything in between.
That help?

[Stellafane]

Hi SBrown. With all due respect, I don't really see what you're hoping to accomplish by posting here. Your threads seem to follow the same general pattern: (1) Ask a question that has been thoroughly discussed and answered in other threads, (2) Become snippy and rude when someone tries to provide an answer you don't like, and finally (3) Spend the rest of the thread complaining how everyone here treats you badly.

Take this very thread for example. Your OP question has been discussed and answered so many times already in this forum, it seems almost inconceivable that you missed it. You certainly couldn't have searched the forum first before posting it. Then, when R.Mackey posts a perfectly civil and reasonable answer (post #5), you reply with a post (#7) that can only be described as snotty and insulting. Why did you do that? What possible reason can you have for being so rude, if you were truly interested in seeking an answer to your question? (And if you weren't seeking an answer, then by definition you're trolling.) Finally, you derail your own thread by asking about irrelevancies (e.g. South Park).

So in all seriousness, I'd really like to know: Why do you do this?

[Gravy]

So in all seriousness, I'd really like to know: Why do you do this?
You're not the only one wondering that, Stellafane.
http://forums.randi.org/showpost.php?p=1726865&postcount=6

[coalesce]

I suspect it's some sort of time passing technique while waiting for real evidence and objective investigation.

Just a thought...

Absolutely 100% correct! Allow me to explain....

For the past few months, this board has been bombarded with people from the Loose Change camp who wholeheartedly believe that the WTC was a set-up by the government. All manner of theories were presented as to how the gub'mint planted explosives in the steel columns during construction, how to towers couldn't POSSIBLY pancake the way they did and that it HAD TO BE A PLOT. Well, as someone who had to evacuate my office in the Empire State Building that morning and then watch the towers collapse before my eyes, I take conspiracy theories like this a little more personally that others. If you search this board, you will find more than enough links that rationally show that what we saw is exactly what happened. No evil neo-cons, no shoddy construction, just plain ol' physics.

The tone of your opening post, SBrown, suggested to me that you were convinced that it had to be more than just weakened steel, brought about by unimaginable temperatures and blunt-force trauma, collapsing upon itself. If I misinterpreted your opening post as an intent to expose an evil one-world gub'mint plot, but instead as an open-minded inquiry, then I apologize for jumping to a hasty and incorrect conclusion. If, however, you feel that it was a plot, then I must invoke the Chewbacca defense because that is all the seriousness that the plot, and all those who believe in it, deserve.

Michael

[SBrown]

I have, and it is funny and has nothing to do with buckling and columns..
SBrown, if you are seriously asking, I propose an experiment for you.
Go get a length of spaghetti--uncooked, please. you will notice that it is very strong if you try to push both ends lengthwise--in compression. IF you hold it in the middle, with one end on the table, uou can put something very heavy on the other end, and it will not break. Now, remove your grip from the middle, and watch it break into a large number of pieces.
How much weight a column will support is a function of its slenderness ratio, that is, its total length compared to its cross-sectional geometric moment-of-inertia and area.
So, with 6 pieces of 2inch length spaghetti set verticaly, you could support say, the first 2 volumes on the Encyclopedia Britannica. Make those lengths 4 inches, and things get wobbly. 6 inches, and you have little bitty pieces of spaghetti again.
That is exactly what happened when several floors got taken out--the 2" chunks are now suddenly 6 inches long-the hand was removed.
The floors, you see, made the columns keep their relationship to each other. They were the hand in the middle of the stick. When that went away. they snapped-broke, bent and everything in between.
That help?


No because pasta is not 4foot thick steel.

[Meffy]

No because pasta is not 4foot thick steel.
So now it's four-foot rebar on three-inch centers?

[Levantine]

No because pasta is not 4foot thick steel.

It's also not holding up tons of building. What was used was what we call an 'example'. In this case, the example was an experiment regarding how stress can buckle vertical support, but on a smaller scale. In what way does this 'example' not enhance your understanding? Are you being intentionally dense or do you need further explanation of how the example was similar to the actual collapse of columns being described?

[SBrown]

So now it's four-foot rebar on three-inch centers?

four foot rebar? What are you talking about?

[Meffy]

If you did not mean rebar, please explain your reference to four-foot-thick steel.

[Meffy]

No evil neo-cons, no shoddy construction, just plain ol' physics.
That's about it. I loathe so-called neo-conservatism as much as most, and am appalled by construction fraud, but there just ain't nothin' here to get indignant at.

Except the woos playing on honorable people's graves.

[SBrown]

It's also not holding up tons of building. What was used was what we call an 'example'. In this case, the example was an experiment regarding how stress can buckle vertical support, but on a smaller scale. In what way does this 'example' not enhance your understanding? Are you being intentionally dense or do you need further explanation of how the example was similar to the actual collapse of columns being described?

I guess you are not aware that the towers were designed to support six times the load that they supported (four times was the code at the time). Of course they easily did this and redistributed their weight as they were designed. Using pasta as an example is just ludicrous.

[Meffy]

SBrown, what is your level of understanding of structural engineering? Training -- formal, informal?

[edit] I ask because others who know far more about this sort of thing than I do will want to know how much you already know, so as not to repeat things you already understand. You'll want to know your stuff, because some of the people here work with this sort of thing day in and day out, and will find the errors in flawed arguments before you can say "boo."

[Levantine]

That's about it. I loathe so-called neo-conservatism as much as most, and am appalled by construction fraud, but there just ain't nothin' here to get indignant at.

Except the woos playing on honorable people's graves.

I've been keeping up with all the arguments and that's really what irks me as a lurker. There's no (good) reason to do what the CT's do. I understand there's a certain psychology to it but for the love of Bob... I don't know anyone who wasn't a degree separated from the tragedy. It leaves marks and these guys seem to be using their patented CT Whiteout (gets the joooos out!) to re-write history.

I thank a random deity every time I meet an average person who doesn't think the CT's are worth a listen. Every rational mind keeps us further away from insanity as a nation (world).

[SBrown]

If you did not mean rebar, please explain your reference to four-foot-thick steel.
Rebar is used to reinforce concrete.

The WTC's had 47 four foot thick steel colunms that ran the entire lenght of the building throught the core. Take a look at the picture I posted.

http://i5.photobucket.com/albums/y171/karanjasjas/wtc-1.jpg

[Meffy]

You got that right, Levantine. Sometimes it gets hard not to become angry with the folks who make a hobby-horse of this tragedy. I try, for good or ill, to be patient.

[Gravy]

So now it's four-foot rebar on three-inch centers?
Oh, Noooooooooooooooooo!

The Law of Conservation of Christophera

In an internet forum, Christophera is neither created nor destroyed.

[Meffy]

@SBrown: What, no Invisicrete? "None genuine without this signature."

@Gravy: :-D I like, I like. [edit] (Glad someone got it.)

[Levantine]

You got that right, Levantine. Sometimes it gets hard not to become angry with the folks who make a hobby-horse of this tragedy. I try, for good or ill, to be patient.

You do a darned fine job too. Better than I do certainly. Which is why I keep my big mouth shut most of the time. Wouldn't want an angry skeptic to hurt those little CT feelings and ruin the "cause".:D

[Gravy]

Rebar is used to reinforce concrete.

The WTC's had 47 four foot thick steel colunms that ran the entire lenght of the building throught the core. Take a look at the picture I posted.

http://i5.photobucket.com/albums/y171/karanjasjas/wtc-1.jpg
Are you claiming that there were columns of 4-foot-thick solid steel? Are you sure you don't mean 4-inches thick?

[Meffy]

Are you claiming that there were columns of 4-foot-thick solid steel?
Made me think of the anecdote about Thomas Edison (IIRC) and the cubic foot of copper.

[gumboot]

I think it should be pointed out...

The 47 core columns were not single lengths that ran the entire way from the foundations to the top of the buildings. There were a series of columns (can someone confirm their length?) bolted together in sections. Hence why they broke apart the way they did - the forces of the collapse undermined the bolts holding each section.

If they single continuous columns, yes, your concerns would be valid. However they were not.

Think of it like a lego building. If you smash a lego building it is highly likely you will not actually break any of the lego pieces. However those pieces will break apart from each other. A great deal (though not all) of the WTC's steel collapse appears to be disintegration into componant steel elements.

-Andrew

[Gravy]

I think it should be pointed out...

The 47 core columns were not single lengths that ran the entire way from the foundations to the top of the buildings. There were a series of columns (can someone confirm their length?) bolted together in sections. Hence why they broke apart the way they did - the forces of the collapse undermined the bolts holding each section.

If they single continuous columns, yes, your concerns would be valid. However they were not.

Think of it like a lego building. If you smash a lego building it is highly likely you will not actually break any of the lego pieces. However those pieces will break apart from each other. A great deal (though not all) of the WTC's steel collapse appears to be disintegration into componant steel elements.

-Andrew
A continuous column will still buckle when it exceeds its carrying capacity, though. A 1368-foot single-piece WTC column would still need all that lateral support.

[hellaeon]

sbrown, perhaps you should read the other thread with christophera or whatever his name is.

[Pidge]

My dad has an expression he's alleged he's used when teaching senior high school students:

Were you born thick, or did you work at it?

This seems apt right now...

[gumboot]

I guess you are not aware that the towers were designed to support six times the load that they supported (four times was the code at the time). Of course they easily did this and redistributed their weight as they were designed. Using pasta as an example is just ludicrous.


I thought I would share something interesting about high-rises.

The heat output in high rise office buildings in most of the western world has increased by a factor of 6 in the last thirty years.

This is for two reasons.

Previously, a single person would be allocated an office space. Now that same office space (on average) is occupied by three people.
The second reason is that now each of these three people has a desktop computer (as opposed to a desk and some pens and paper).
A desktop computer (on average) gives the same heat output as one person.
Thus the factor of six increase in heat output.

This is interesting, because it also relates to load. Not only are three times as many people working in a given high-rise (on average) but this results in an increase in overall load weight. Everyone has a computer. Three-times as many desks. Three times as many wastebaskets. Three times as many bathrooms. Three times as many water-coolers, and so forth...

Add to that the additional air conditioning system required to deal with 6x the internal heat production of the original design, and you have a considerable increase in occupancy load on the structure, compared with at the time of design.

So a load redundancy factor of 6 at design, becomes a lot lower in 2001.

In addition to that, a redundancy is based on constant load. Such factors do not take into acount a quarter of the building collapsing through four destroyed floors onto the rest of the building at 9.8ms^2.

Lastly, the design of a building like the WTC relied on overall structural integrity because load was carried by the complete structure - not just by a central element. The aircraft impact disrupted all three elements of the building's structure at once - the exterior columns, the core, and the floor trusses. The fires continued to undermine all three elements across the area of impact and above.

None of these are things that are taken into account in building design.

-Andrew

[Ducky]

How many f***ing times do we have to answer these questions and debunk these myths?

[Levantine]

How many f***ing times do we have to answer these questions and debunk these myths?

You should know by now the answer to that is 'just one more time', every time.

[SBrown]

You guys do a good job here as a group of ridiculing people with a separate view of your own here. Separately you guys are weak, as a group you guys are strong. You are simply a herd. It is ok I never wanted to be part of your group anyways, reminds me of a cult.

[Levantine]

You guys do a good job here as a group of ridiculing people with a separate view of your own here. Separately you guys are weak, as a group you guys are strong. You are simply a herd. It is ok I never wanted to be part of your group anyways, reminds me of a cult.

I don't want to alarm you Sbrown, but strangely enough, the feeling is mutual. Your point of view is based on feelings of course, while our hive mind position is based on facts. Not a character judgement, just saying. The Foundation is Mother, the Foundation is Father.

In seriousness though, the point is that this has been discussed and beaten into the ground. OVER and OVER again. And over even again! You don't like it here because you have to THINK to survive. You don't want to think. You want to believe. Which is fine, but it doesn't make you right. Also, it's generally considered bad form to walk into someone's home and accuse them of being rude when you've done nothing but ignore and insult. Especially in a house of learning which this forum is for most of us.

I'm not nearly as educated as many of the people here, but I can research. And I can weigh the evidence. The simple fact is you don't have evidence on your side... why would anyone here do anything but question your views?

[Gravy]

You guys do a good job here as a group of ridiculing people with a separate view of your own here. Separately you guys are weak, as a group you guys are strong. You are simply a herd. It is ok I never wanted to be part of your group anyways, reminds me of a cult.
If you'll just stick to the point of your OP, you'll learn a lot. Do you have anything to add? Do you realize that the columns were hollow? Have you learned anything new about the subject you introduced?

eta: If you'd like to debate me separately, I'll be glad to oblige. Shall I set up a new thread?

[tacodaemon]

I'd love to watch SBrown and Christophera battle it out over whether there were steel core columns in the WTC or not, and whether or not the columns were smaller in the middle of the core (as Christophera likes to claim). Continuing the Star Wars theme: It would be like making the wampas fight each other in the "Shadows of the Empire" video game so you don't have to kill them yourself.

Anyway, the NIST report NIST NCSTAR 1-6D has computer-generated pretty pictures showing how the exterior columns on the north tower's south face appear to have been bowing inward, which caused the top of the tower to tilt toward the south during the collapse. You can see a couple of pages showing both the interior and exterior displacements here:

i3.tinypic.com/15p3mrp.jpg

[Stellafane]

You guys do a good job here as a group of ridiculing people with a separate view of your own here. Separately you guys are weak, as a group you guys are strong. You are simply a herd. It is ok I never wanted to be part of your group anyways, reminds me of a cult.

Hi SBrown. I hope you'll notice that I did not ridicule you, I only asked a reasonable, germane question, which in case you missed it I'll post again: Why do you post here? What is is that you're truly hoping to accomplish? Your original question was politely answered, to which you yourself responded with ridicule. Why did you do that?

[gumboot]

A continuous column will still buckle when it exceeds its carrying capacity, though. A 1368-foot single-piece WTC column would still need all that lateral support.

Absolutely. But SBrown's original post seem to imply he was skeptical of these huge columns neatly snapping into sections all along their length in perfect unison with the rest of the collapse.

Had they been single huge columns, this would be a valid point. The beams would no doubt buckle, snap, and fall apart, but I would be surprised if it was as uniform and "neat" as the collapse appeared (no shards of core columns jutting out of the dust and what have you).

But if these columns are actually sections, bolted together, it makes perfect sense that they snap off one after the other along with the overall collapse.

-Andrew

[SBrown]

Hi SBrown. I hope you'll notice that I did not ridicule you, I only asked a reasonable, germane question, which in case you missed it I'll post again: Why do you post here? What is is that you're truly hoping to accomplish? Your original question was politely answered, to which you yourself responded with ridicule. Why did you do that?

I post here for the same reason everyone else does....cause they can.

[SBrown]

I'd love to watch SBrown and Christophera battle it out over whether there were steel core columns in the WTC or not, and whether or not the columns were smaller in the middle of the core (as Christophera likes to claim). Continuing the Star Wars theme: It would be like making the wampas fight each other in the "Shadows of the Empire" video game so you don't have to kill them yourself.

Anyway, the NIST report NIST NCSTAR 1-6D has computer-generated pretty pictures showing how the exterior columns on the north tower's south face appear to have been bowing inward, which caused the top of the tower to tilt toward the south during the collapse. You can see a couple of pages showing both the interior and exterior displacements here:

i3.tinypic.com/15p3mrp.jpg


Is that really Star Wars or is it really some hip cartoon?

[hellaeon]

You guys do a good job here as a group of ridiculing people with a separate view of your own here. Separately you guys are weak, as a group you guys are strong. You are simply a herd. It is ok I never wanted to be part of your group anyways, reminds me of a cult.

Have your seperate view, but what use is it if its actually wrong in reality. None of this panzy 'oh its ok, you have a different opinion' rubbish. Your understanding of the sciences at hand are wrong and your questions get answered only for you to dispute the answer with your incorrect science.
Do you want to walk around thinking its your way or the highway? Why is it so hard to be humble and accept your wrong? God man, I dont care and I dont think anyone cares if your wrong but myself and others here do get p*ssed when people who are wrong will fly in the face of reailty and still think they are right!.

Stuff it. Im not right. IM LEFT.

[SBrown]

Have your seperate view, but what use is it if its actually wrong in reality. None of this panzy 'oh its ok, you have a different opinion' rubbish. Your understanding of the sciences at hand are wrong and your questions get answered only for you to dispute the answer with your incorrect science.
Do you want to walk around thinking its your way or the highway? Why is it so hard to be humble and accept your wrong? God man, I dont care and I dont think anyone cares if your wrong but myself and others here do get p*ssed when people who are wrong will fly in the face of reailty and still think they are right!.

Stuff it. Im not right. IM LEFT.


Nothing was proven wrong.

[tacodaemon]

Is that really Star Wars or is it really some hip cartoon?

It's an officially licensed video game based on the Star Wars series. Anyway, did the picture I linked to help any? The full collapse report NIST NCSTAR 1-D prepared by NIST, which uses finite element analysis performed for NIST by the engineering firm of Simpson Gumpertz & Heger, has pages and pages of charts, computer models, and annotated photographs showing the varying loads on the columns of both towers prior to collapse. Here you go:

wtc.nist.gov/NISTNCSTAR1-6D.pdf

[Gravy]

I post here for the same reason everyone else does....cause they can.
Actually, I imagine that most people here post because they're interested in having rational discussions about interesting subjects. Your description of why you post here sounds awfully trollish to me.

Now, you accused us of hiding within the group, and said we were individually weak. I challenge you to prove that. Shall I set up a separate forum where you and I can debate 9/11 issues without interference?

What will it be, SBrown? You're not an intellectual coward like those Loosers at the LC forum, are you?

[SBrown]

It's an officially licensed video game based on the Star Wars series. Anyway, did the picture I linked to help any? The full collapse report NIST NCSTAR 1-D prepared by NIST, which uses finite element analysis performed for NIST by the engineering firm of Simpson Gumpertz & Heger, has pages and pages of charts, computer models, and annotated photographs showing the varying loads on the columns of both towers prior to collapse. Here you go:

wtc.nist.gov/NISTNCSTAR1-6D.pdf
Nope.

[SBrown]

Actually, I imagine that most people here post because they're interested in having rational discussions about interesting subjects. Your description of why you post here sounds awfully trollish to me.

Now, you accused us of hiding within the group, and said we were individually weak. I challenge you to prove that. Shall I set up a separate forum where you and I can debate 9/11 issues without interference?

What will it be, SBrown? You're not an intellectual coward like those Loosers at the LC forum, are you?


How about you come on my podcast?

[Gravy]

How about you come on my podcast?
Will you debate me here? Yes or no.

[SBrown]

Will you debate me here? Yes or no.
Nope this is not neutral ground and I am BBq'in and drinking beers.:D

[Ducky]

Your podcast in neutral ground?

Yeah right.

[Stellafane]

I post here for the same reason everyone else does....cause they can.

Actually, that's not the reason I post here, nor do I suspect it's the primary reason the vast majority of people that participate in this forum do. After all, I could post in a million other forums. I choose to post here because I want to discuss things that interest me, learn stuff, and on rare occasions share a piece of knowledge or an opinion. To state "because I can" as your sole reason for posting here is, in my view, an admission on your part that you don't really have a purpose, and that you're not really interested in the civil and honest discussion of issues and topics. After all, why should anyone here even bother responding to someone who has absolutely no interest in what they have to say, but only posts because "they can"?

So, do you really want to leave that as your answer to my question?

ETA: And you didn't answer my other question: Why did you post a rude and snotty reply to R.Mackey in post #7, when his post simply answered your original question, reasonably and politely? (And please don't say "because I can" again, unless you're willing to run the risk of sounding exceedingly juvenile.)

[Gravy]

Nope this is not neutral ground and I am BBq'in and drinking beers.:D
As I said, only you and i will be able to post. No interference. LOTS of people will read it though.

Tomorrow, the next day, whenever it's convenient for you.

Yes or no?

[SBrown]

As I said, only you and i will be able to post. No interference. LOTS of people will read it though.

Tomorrow, the next day, whenever it's convenient for you.

Yes or no?

Sure as long as it is on my podcast.

[Wowbagger]

SBrown, if you think all of our suggestions are wrong. I'd love to know what your theory is. How do YOU think the core supports weakened, and more importantly, what evidence do you have to back that theory up?
Or, alternatively, if you do not have an answer of your own, why are you so quick to dismiss our answers?

You think we are a cult simply because we provided some factual answers to your question? How is your behavior is any different from cult-like mentality?

[Ducky]

Wowbagger, good point. How is SBrown's posting any different than, say, Kurious_Kathy?

She feels the need to come tell us we're all wrong to show her cult she fights the good fight.

[kookbreaker]

Sure as long as it is on my podcast.

Have we determined prior to this that this is a Roxdog sock? i was away for the weekend.

[SBrown]

Have we determined prior to this that this is a Roxdog sock? i was away for the weekend.

Do you guys always speak in code here?

[Gravy]

Sure as long as it is on my podcast.
Another Looser declines the challenge of a rational one-on-one debate. That's the second one today, by the way (I dealt with another one by email). Aren't there ANY Loosers who aren't cowards?

[kevin]

I think it should be pointed out...

The 47 core columns were not single lengths that ran the entire way from the foundations to the top of the buildings. There were a series of columns (can someone confirm their length?) bolted together in sections. Hence why they broke apart the way they did - the forces of the collapse undermined the bolts holding each section.


they were this long:
http://forums.randi.org/imagehost/578944987b4f05c6f.png

Notice too that although they may be 4' on a side (I haven't actually confirmed that dimension) they were hollow.

[Gravy]

Do you guys always speak in code here?
Please provide a link to your podcast.

[RandFan]

No because pasta is not 4foot thick steel. The principle is the same. Do you understand physics? A paper plane isn't a 747 but it can exhibit the same principles of aerodynamics.

Are you just being obtuse? Do you not understand the concept of principles and how a principle of physics can be scaled and applied to an object of different properties?

The spaghetti example was given you to teach you a principle. Much like what is done in science class. You did take science class didn't you?

[Levantine]

Another Looser declines the challenge of a rational one-on-one debate. That's the second one today, by the way (I dealt with another one by email). Aren't there ANY Loosers who aren't cowards?

If they weren't cowards, they probably wouldn't be Loosers. They'd be man (or woman) enough to review the evidence and admit fault with their position. Or at least show a willingness to do so.

[RandFan]

Sure as long as it is on my podcast. Why, what difference could it possibly make?

[Gravy]

If they weren't cowards, they probably wouldn't be Loosers. They'd be man (or woman) enough to review the evidence and admit fault with their position. Or at least show a willingness to do so.
Good point. I never quite looked at it that way.

[kevin]

Why, what difference could it possibly make?

It's about retaining the power of the all mighty editor. cut out the parts that make you look bad, and trim up the "unnecessary" comments from the other person to clarify (i.e. reverse) there meaning.

oh wait, you were asking sbrown. my bad.

[RandFan]

It's about retaining the power of the all mighty editor. cut out the parts that make you look bad, and trim up the "unnecessary" comments from the other person to clarify (i.e. reverse) there meaning.

oh wait, you were asking sbrown. my bad.I know, SBrown will have difficulty answering.

[SBrown]

Do you guys serve Randi or Gravey? Cause right now you look like a bunch of Gravey lackeys.

[Gravy]

Do you guys serve Randi or Gravey? Cause right now you look like a bunch of Gravey lackeys.
Know what you look like? A sad, ignorant coward.
Who can't even spell "Gravy" correctly.

[SBrown]

Know what you look like? A sad, ignorant coward.
Who can't even spell "Gravy" correctly.
Nope wrong like usual.

[Gravy]

Nope wrong like usual.
That's right, I forgot to add "troll." Now, since you have noting to add to this discussion forum, please troll elsewhere. Your behavior is childish, unpleasant, and unnecessary. You'll always be welcomed back here if you learn to behave like an adult.

[SBrown]

That's right, I forgot to add "troll." Now, since you have noting to add to this discussion forum, please troll elsewhere. Your behavior is childish, unpleasant, and unnecessary. You'll always be welcomed back here if you learn to behave like an adult.

Childish?

You called me an ignorant coward.......:boxedin:

All I have seen from you is childish, yet you represent the cult, I do not.

[Gravy]

Ignore feature, meet SBrown. His first experience with beer has made him cranky.

[Pardalis]

Or crankey.

[SBrown]

Ignore feature, meet SBrown. His first experience with beer has made him cranky.
OHES NOEHS so you now you have to ignore me.......:jaw-dropp

[RandFan]

Do you guys serve Randi or Gravey? Cause right now you look like a bunch of Gravey lackeys. Oh nock it off. Stick to argument and lay off the BS. You will either debate him or you won't.

Which is it?

[Hellbound]

Rebar is used to reinforce concrete.

The WTC's had 47 four foot thick steel colunms that ran the entire lenght of the building throught the core. Take a look at the picture I posted.

http://i5.photobucket.com/albums/y171/karanjasjas/wtc-1.jpg

No, it did not.

You are incorrect.

There were either 44 or 47 columns (depending on which tower).

The outer columns (ringing the core) were about 52" by 22". But they were not solid steel. They were a box made of 5" thick steel.

The interior columns were much smaller, 36" by 16" IIRC, and were made of 2" thick steel.

Nowehere in the buildings did "4 foot thick steel" exist.

Another thing to understand is the difference between static load and dynamic load. The buildings were built to support 6 times the static load (actually, I recall hearing 8, but either way). The static load is similar to the maximun breaking weight of a piece of rope. It's the total force it can withstand, not the mass of objects.

As an example, take a rope that has a maximum breaking strength of, say, 1000 lbs. If you buy this in a store, it'll be listed as a 250 lb. working strength. But you could tie up 100 lbs. on it. However, if you tug it while it had that 1000 lbs, it'd break. Dynamic load includes not just the weigth being supported, but the force with which that weight pushes, as well.

Likewise with the towers. When the upper floors fell, That acceleration and impact was far more than 6 or 8 times the static load. Even considering static load, you had 6 to 30 (approximately) floors above the impact sites that crashed onto the floors below them. In both cases, that would go over the 6 times static load limit, causing the impacted floor to give. When it hit the next one, you get a repeat of the process all the way down.

Another thing to consider is that the core was designed for the buildings weight ot be distributed up and down. If the entire weight of the building was statically attached to the core at one point, it would fall as well.

[azazal]

I figured it out; I know how the illuminati did it. They didn’t need to drill holes into the concrete to plant the charges. They were flushing cherry bombs, made of C4 and thermite, down the toilets. See they had several hundred MIBS go into the WTC on the night of 9/10. They went and flushed enough charges to clog the pipes in the core, so then when activated they took out all the supports. It makes perfect sense now;)

Quick, I'll make up a web page expounding my idea to the world, because we all know that shouting from an internet soapbox is the only way to get the "truth" out. And the Illuminati never reads the net, and will never track me dow .................................................. ................................



THIS MESSAGE HAS BEEN TERMINATED. MOVE ALONG CITIZEN, NOTHING TO SEE HERE.

[kevin]

I figured it out; I know how the illuminati did it. They didn’t need to drill holes into the concrete to plant the charges. They were flushing cherry bombs, made of C4 and thermite, down the toilets.

No, they just got enough people to flush all the toilets at the same time!

[Legalduck]

Do you guys serve Randi or Gravey? Cause right now you look like a bunch of Gravey lackeys.

Hardly. Many of us point to Gravy because he did a very extensive, well-documented, and logical examination of popular 9/11 myths and LC. This examination has stood up to review and attack by CTs. As he has spent so much time in researching the subject well, he is ina good position to add to the discussion. We're not lackeys (except to Global Conspiracy Network. Number 72300 reporting in sirs!) . No one can know everything. If I had a question about 9/11 myths, I would ask Gravy (though other input would be more than welcome). If I wanted to know about explosives I would ask Huntsman. If I wanted know about the scams psychics were pulling with missing children I would ask KellyJ. There is a large volume of useful info here, if you're willing to look. This includes a several threads dealing with the issues of the WTC collapse discussed. Not only Gravy, but many others contributed their knowledge and, more importantly, their questions.

While there has been some insults hurled, most of the criticism has been of your argument, not you. That's what happens on a skeptics board. Someone presents an argument. That argument is vigorously examined. We look to logic and rationality. Just because YOU give a theory weight does not make the theory logical or even special. In fact, your beliefs should be irrelevant. The theory simply is. It is supported by verifiable facts or it is not. If you post here, you should expect your theory to be attacked. Except demands for evidence.

I cannot speak for the other posters here, but I suspect there will be some agreement (which has nothing to do with us being a herd). If we seem aggressive or determined to demand facts, its because we've had to deal with irrational people before. We deal with this over and over again.

Do you guys always speak in code here?

Lastly, we're not talking in code when we mentions socks. A sock, or sock puppet, is a fake registration. If a person has been banned or suspended or is generally infamous (see Killik, 1inChrist), they create a fake persona to continue posting. Occassional, a person will have several socks to create the illusion of support (Sock 1: "I think X." Sock 2: "You know, you're right!", Sock 3: "I think Sock 1 is brilliant!"). Your posts sound remarkably like a known troll. I hope this is not the case and you're here for honest discussion.

[tacodaemon]

Notice too that although they may be 4' on a side (I haven't actually confirmed that dimension) they were hollow.

Have any truthers claimed yet that the hollow steel columns were filled with explosives when the building was built, like how Christophera thinks some of the "concrete core" was C4 instead of concrete? I'm afraid to look.

[azazal]

Have any truthers claimed yet that the hollow steel columns were filled with explosives when the building was built, like how Christophera thinks some of the "concrete core" was C4 instead of concrete? I'm afraid to look.


OK, that's it. On lunch I'll get pictures of the WTC 2 support column that was set up as a memorial. All steel, hollow and no burn makrs form cutting.

[Mancman]

The floors, you see, made the columns keep their relationship to each other. They were the hand in the middle of the stick. When that went away. they snapped-broke, bent and everything in between.
That help?

Yeah, exactly. The floor trusses provided the lateral support for the core and perimeter columns. The fires weakened many of these and the resultant sagging not only lessened the load bearing capacity of the columns by removing rigid lateral support but also by pulling the columns out of place by upto 55in on the south face of the North Tower, according to NIST.

How long can a 13.5in deep perimeter column support the columns of the floors above whilst being pulled inwards 55in? Answer: Not long.

[Meffy]

Given comments in other threads I suspect SBrown understands this but is pretending ignorance as a pretext for stirring up trouble for "fun."

[Wowbagger]

Is SBrown gone, now? If so, then Darn! My questions weren't answered: How does SBrown think the suports collapsed? Based on what evidence?

[kevin]

Is SBrown gone, now? If so, then Darn! My questions weren't answered: How does SBrown think the suports collapsed? Based on what evidence?

On suspension for spamming the forum. I forget for how long.

[Stellafane]

Is SBrown gone, now? If so, then Darn! My questions weren't answered: How does SBrown think the suports collapsed? Based on what evidence?

Doesn't really matter if she was suspended or not, I doubt you'd ever get a straight answer to your question from her either way.

[kevin]

Have any truthers claimed yet that the hollow steel columns were filled with explosives when the building was built, like how Christophera thinks some of the "concrete core" was C4 instead of concrete? I'm afraid to look.

I'm waiting for them to claim it was assembled with explosive bolts.

http://www.mcselph.com/exbolt.html