That’s a fair statement. I agree.
I am not moving any goal posts. I have been talking about the TONS of STEEL and TONS of CONCRETE on every level of the towers since I got here. It just so happens that there are about FOUR DIFFERENT REASONS for wanting that information. The fact that it takes more energy to heat more steel to a given temperature is one of them.
There is a 56 min. time limit to weaken the steel on the south tower and a 102 minute limit on the north tower. So anyone claiming that fire brought the buildings down must explain how a hydrocarbon fire did it within that time. So why don’t they bring up the quantity of steel that must have been in the fire? Doesn’t it help their case? 
But since more steel means more inertial it is relevant to the plane impact and the collapse. Since there are people talking about the potential energy of the towers then how much steel is how high is relevant to that.
It is not my fault that you don’t track all of the relevant factors simultaneously. It’s called PHYSICS.
psik
I would also think the quality of steel would be of some import as well.
Again: What is your point? If the plane+fire didn’t bring down the building, Psikey, WHAT DID?
Well we know the quality of steel held the buildings up for 28 years.
I don’t care what did it yet. As long as people BELIEVE the planes did it they aren’t going to look.
I am trying to eliminate a negative.
How can we know what could do it if we don’t know the distribution of steel and concrete?
People just want to BELIEVE the planes did it because that makes life simple for them.
This is very curious:
psik
Curious only in the sense that the maker of the video is just a nut claiming that no human was controlling the plane.
I don’t even understand… what’s the point of doing it remotely, if you’re still going to bother having hijackers on the plane? What would remote piloting accomplish over having hijackers take the controls locally?
The factors at play during the destruction of the Twin Towers, all added together, make sense.
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The initial impact of the airplane severed a percentage of peripheral columns and a percentage of the core columns. The undamaged columns, with the aid of the hat trusses, were able to redistribute the load, which is why the buildings stood as long as they did.
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The initial impact of the airplane produced a localized area of XX floors where the fireproof material was knocked off the floor trusses.
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The initial impact of the airplane, followed by the detonation of the fuel, set up a localized pattern of fire on the affected floors (as well as other places, such as the fuel traveling down the elevator shafts to the lobby, etc.) The jet fuel is important for 2 reasons, really: first is the visible fireball, which of course consumed much of the fuel itself, and second is that it was the accelerant that started the reams of paper, cubicles, desks, etc. on fire.
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Regardless of what was going on in the rest of the building (fire, no fire, fireproofing, no fireproofing) the localized area continued to burn, heating the steel floor trusses–without fireproofing material anymore–enough to expand.
Tangent–
A hydrocarbon fire will be MORE than enough to cause steel to heat, plasticize, and expand. The sun will do it just fine–railroad companies have special practices to minimize expansion and contraction of their steel rails, such as laying it at a neutral temperature, but it still happens, and the methodologies of continuous welded rail take it into account. Expansion gaps are placed at critical intervals to give the steel, which cannot move laterally (due to being affixed to the ties,) a place to expand linearly.
Regardless, the sun is hot enough to overcome those safeguards, heating the rail to a point where it finds a weak spot in the spike/tie/joint system and buckles outward–a sun kink. Sun kinks are particularly bad because the rail often does not break, which allows the track circuit electricity to continue to flow, and does not throw red signals.
Railroads often have slow orders when the ambient temperature gets high enough to produce sun kinks–and I’m only talking about roughly 100 degrees F here.
The point is that it doesn’t take the steel getting anywhere near melting point, or even into the thousands of degrees, to expand. The plain jane ambient temperature of the southern US will do it just fine.
With regard to the WTC, you have a sustained fire heating unprotected structural steel, and it’s gonna want to expand (and if the temperature goes down, contract.)
Since the framework of the Twin Towers was so innovative, the floor trusses themselves secured the core columns to the perimeter columns, which, among other things, held the building square (there were viscoelastic dampers in the connections to mitigate the buildings’ sway, of course, but the linkage between the inner columns and outer columns, aside from the hat truss up top, was the actual floor truss.
Upsetting the already delicate balance is the fact that all the surviving columns were carrying and distributing more than their designed loads. It was only a matter of time before the fire caused enough heat for one floor truss to fail, and at that point the building gave up the ghost–there was simply no way to reassign the loads anymore.
There’s no need for a conspiracy, thermite, squibs, or anything else…the buildings fell because of their design features–tube-within-a-tube, the ablation of the fireproofing, and the fact that steel only needs a relatively small amount of heat to lose strength.
Here’s an image of a sun kink. Keep in mind the steel is misaligned only because of the thermal expansion caused by the sun.
http://farm4.static.flickr.com/3311/3656804235_bba9f4543b.jpg
Why try to eliminate the patently obvious if you have no other theories to stand behind? It would be like me trying to explain why the day is warmer than night while arguing that the Sun can’t be the answer because we don’t know its distribution of mass. :rolleyes:
So, regardless of your “trying to eliminate a negative”, whatever that means, what is it that you think brought down the towers? Please answer this simple question before posting yet another “why don’t we know the…” statement. We have been quite patient and deserve the respect of an answer:
What do you think brought down the towers?
Too late for ETA:
Do you think the buildings were going to collapse that day if they weren’t hit by planes?
I don’t want to be snarky, I’m just genuinely curious as to what you think would’ve happened to the towers if the planes didn’t h0them. You obviously don’t think the plane crashes+fires brought them down, which, to me, implies that you think they were going to come down regardless. Is this true?
And, I’ll point out again, you haven’t yet indicated why you think that particular piece of information is critical to know, despite repeated requests from both me and others. The fact that you insisted you needed a mass distribution to calculate tower displacement on impact–a completely erroneous assumption–and made a potential energy model that has no bearing on the full-scale tower makes me think that the rest of your physics is probably erroneous.
So, let me repeat some questions I asked you earlier, but you ignored:* If *you had an exact mass distribution, what calculations or models would you do or make that you couldn’t without an *exact *mass distribution? What question are you trying to answer, and what type of answer do you expect? How would the answer be different than if you bounded the problem with an over- and under-estimate of the mass? Are you *sure *there are not *other *factors involved that introduce more error than just using an estimation of the mass?
You’ve got a good example here of why I’m asking you to think about the physics before plunging ahead and insisting on knowing the mass distribution.
Suppose you knew the exact amount of steel on each floor of tower. What would you be able to do that you can’t do now? I suspect you’re going to say you want to do some sort of calculation relating the energy in the fuel to the heat rise of the steel. If so, the uncertainty due to not knowing the exact steel mass is outweight by the uncertainty of not knowing the amount of other combustibles present, and by the fact that only a tiny amount of steel in the right place need be weakened to initiate collapse.
As I recall, you were the one talking about potential energy when you first joined the thread. I refer you to the questions above.
So far your application of physics has been either misleading, incomplete, or downright wrong. My impression from your previous posts is that you’re working backwards, by constructing a model first, and then trying to match up the behavior of the model to the real buildings. Rather, you need to pinpoint *first *what question about the real building you want to answer, and *what important effects *need to be included in the model, before you build the model.
Perhaps then we can answer the question that’s been plaguing scientists for ages: Can hamsters fly planes?
More importantly, can they fly planes that are attempting to take off from treadmills and what would happen if the plane and treadmill were on the back of a truck that went under a low bridge?
And if the truck were travelling at the speed of light and turned its headlights on, what would happen then?
[QUOTE=42fish]
And if the truck were travelling at the speed of light and turned its headlights on, what would happen then?
[/QUOTE]
The plane would take off from the treadmill, obviously. You guys really need to be able to grasp the physics of all this better…
-XT
More likely, the truck would take off from the treadmill, and I have a model made of marshmallows and a sanding belt to prove it.
:dubious: What’s the specific gravity of the marshmallow?? If you don’t know that to within a high level of accuracy your model would obviously demonstrate that it’s impossible that ANY of the WTC buildings actually fell!
-XT
And they had all the birdies start flapping their wings?
Because the fires clearly did not have to heat all the steel in the whole building like preheating a turkey, it just had to weaken a few key areas then mass and gravity takes over. It’s called PHYSICS.
You’re forgetting other flammable stuff, like furniture. This one-story 42,000 square foot steel frame (2000 more than a single Tower floor) collapsed in about 45 minutes:
http://cache.daylife.com/imageserve/00sN2pD5LO0WO/610x.jpg
http://cache.daylife.com/imageserve/0aBo8BfdfO5gy/610x.jpg
http://www.charlestoncitypaper.com/imager/charlestons_top_news_stories _of_2007/b/original/1112574/0334/fire.jpg
http://cache.daylife.com/imageserve/09NueSx5WL4L6/610x.jpg
http://msnbcmedia4.msn.com/j/msnbc/Components/Photos/070620/070620_charleston_hmed_5a.hlarge.jpg
http://cache.daylife.com/imageserve/06DAawy1tNfRl/610x.jpg
