Tower Collapse Questions for Critical Thinkers

[triforcharity]

Wow, where do I start with Kyle's idiotic statements.

I will take the one that I find somewhata intersting.

You are not willing to take expert opinions on a subject, because

A: You don't understand it (my guess)

2: You don't WANT to believe it, because you haave been taken for a ride by the idiots thata are in the forefront of the Twoof Movement,

But, yet you will take the few idiots lies that they spew as fact, even though hundreds of engineers, and architects, and people in other related fields tell you are wrong.
Hell, I am not an engineer, and I don't ever claim to be, but when it comes to fire, I do understand that, and am very well versed in it. They wouldn't let me teach if I didn't.
BUT, of course, you don't believe a word that I have said.

Makes complete sense.

 

[dtugg]

My bad, it was late when I made this comment and being tired I completely miconceptulised the height of the floors. Falling 2.25 seconds in free fall from a state of rest is 24.8m, which which is would be over six floors of nothing but air. Granted, the period of free fall didn't start from rest, but there was already some downward velocity at the time, and as NIST reports:

So, there we have about 8 floors of the building providing no observable resisting force.

Sure, Jaydeehess was kind enough to provide the relevant equations:

As Jaydeehess first noted, F_g=mg. So in the last equation he presented we can substitute mg for F_g to get:

mg-F_r=ma

As NIST noted in what I quoted above, the distance traveled for a period of 2.25 seconds was not distinguishable from free fall. As free fall is a situation where the resistive force of air leaves a≈g, we can substitute g for a to rewrite the above equation as:

mg-F_r≈mg

Now we can solve for F_r with simple algebra:

-F_r≈mg-mg

F_r≈0

This means that for every moment of the fall in time over the couse of that 2.25 seconds mentioned above, we have a 32.0 m (105 ft) section of the building providing a resistive force indistinguishable from that of thin air. So again, while it seems many here willingly believe impact damage and office fires caused WTC7 to fall as it did, I have to doubt such a claim just as much as I doubt the claim that Copperfield made the Statue of Liberty vanish into thin air, as both quite simply defy consistently demonstatable laws of physics..

Oh, you were talking about WTC7, I thought you were talking about the towers since that was subject of the thread.

You are aware, twoofer, that interior of the building collapsed before the fascade, correct?

 

[Furcifer]

Given some looking around, I'd bet I could find some structural engineers who believe Copperfield actually did vanish the Statue of Liberty into thin air too, but I'm guessing you'd agree with me that it would be wrong to take their word for it.

Bet? As in wager? As in if you don't find "some" structural engineers who believe Copperfield actually vanished the statue of liberty, vanished meaning some sort of temporary demolecularization or similar state so as not to appear visible, after looking around you'd give me money?

I'd take that bet. I'd take that bet and give you odds if I could include the contingency that any structural engineer you might be able to find must remain practising for at least a year after publically admitting his belief in Copperfields supernatural powers.

I don't actually think you were intending to make a stupid wager. What I think you were doing was trying to make a point. The point being you can find just about anyone in a small enough percentile that will publically deny even the most widely accepted truths. And not only truths, but scientific fact as well.

Which is exactly what we (or rather many many experts in their fields of practice) are telling you about the collapse and the NIST report that describes them.

I don't understand how you can use this Copperfield analogy without seeing how it applies to the CT at large. Or more importantly how it applies to you. You're "some" strucural engineer that thinks Copperfield vanished the statue of liberty.

 

[sylvan8798]

Thanks LashL.. Hope things find you well. I didn't think this fire thing was anything big but my friend was convinced this was another nail in the proverbial coffin. I don't understand how this stuff gets put out there like gospel even to this day.

This is another one of those "all similar things have exactly the same consequences if it works for us" rationales. Like the small plane that accidently hit the Empire State Building in the 40's in the fog and the building didn't collapse, proves that a plane cannot cause a building to collapse.

 

[sylvan8798]

This means that for every moment of the fall in time over the couse of that 2.25 seconds mentioned above, we have a 32.0 m (105 ft) section of the building providing a resistive force indistinguishable from that of thin air. So again, while it seems many here willingly believe impact damage and office fires caused WTC7 to fall as it did, I have to doubt such a claim just as much as I doubt the claim that Copperfield made the Statue of Liberty vanish into thin air, as both quite simply defy consistently demonstatable laws of physics.
I was not disregarding any such credentials, but I can't take them as a rational reason to accept the conclusion you are defending either. If you could design a structure which fire will cause to collapse with a period acceleration indistinguishable from free fall, and consistently demonstrate the ability of your design do so, then I would happily take your conclusion to be a matter of fact. However, since such design would undermine long accepted understandings of the laws of physics, I'm left to disregard your argument here as founded in irrational belief.

Um, no, it wouldn't. Your attempt at an exposition has not demonstrated that such "resistance" must exist or what it would be. According to you, since most engineers and physicists ALREADY believe a structure or portions of a structure can collapse at near free fall acceleration (since we believe the NIST reports), the presence of the belief alone undermines our long accepted understandings of the laws of physics, and we should all be returning to the drawing boards in an attempt to rectify our misbegotten understanding of physics.

Has this happened, to your knowledge? Maybe you should bring it up to the Physics Department at your local U.

 

[Newtons Bit]

My bad, it was late when I made this comment and being tired I completely miconceptulised the height of the floors. Falling 2.25 seconds in free fall from a state of rest is 24.8m, which which is would be over six floors of nothing but air. Granted, the period of free fall didn't start from rest, but there was already some downward velocity at the time, and as NIST reports:

So, there we have about 8 floors of the building providing no observable resisting force.

Sure, Jaydeehess was kind enough to provide the relevant equations:

As Jaydeehess first noted, F_g=mg. So in the last equation he presented we can substitute mg for F_g to get:

mg-F_r=ma

As NIST noted in what I quoted above, the distance traveled for a period of 2.25 seconds was not distinguishable from free fall. As free fall is a situation where the resistive force of air leaves a≈g, we can substitute g for a to rewrite the above equation as:

mg-F_r≈mg

Now we can solve for F_r with simple algebra:

-F_r≈mg-mg

F_r≈0

This means that for every moment of the fall in time over the couse of that 2.25 seconds mentioned above, we have a 32.0 m (105 ft) section of the building providing a resistive force indistinguishable from that of thin air. So again, while it seems many here willingly believe impact damage and office fires caused WTC7 to fall as it did, I have to doubt such a claim just as much as I doubt the claim that Copperfield made the Statue of Liberty vanish into thin air, as both quite simply defy consistently demonstatable laws of physics.

8 floors of columns failed almost simultaneously. It should be no surprise to anyone that these 8 floors of columns provided no resistance to the building above.

 

[Grizzly Bear]

I was not disregarding any such credentials, but I can't take them as a rational reason to accept the conclusion you are defending either. If you could design a structure which fire will cause to collapse with a period acceleration indistinguishable from free fall, and consistently demonstrate the ability of your design do so, then I would happily take your conclusion to be a matter of fact. However, since such design would undermine long accepted understandings of the laws of physics, I'm left to disregard your argument here as founded in irrational belief. Please don't take that as an insult though, as knowing we all lack omniscience, I can't rightly expect any of us to be free of irrational beliefs. Given some looking around, I'd bet I could find some structural engineers who believe Copperfield actually did vanish the Statue of Liberty into thin air too, but I'm guessing you'd agree with me that it would be wrong to take their word for it.

This is my dirty secret...






















http://img38.imageshack.us/img38/6154/booksr.jpg

What's that look for? Where you expecting Pr0n linkz!?

 

[alienentity]

Kylebisme wrote comparing the collapse of WTC7 to a David Copperfield stunt..'as both quite simply defy consistently demonstatable laws of physics'

Which laws of physics does WTC7 defy?

 

[dafydd]

I'm still waiting to hear what kylebisme's engineering qualifications are.

 

[Furcifer]

This is another one of those "all similar things have exactly the same consequences if it works for us" rationales. Like the small plane that accidently hit the Empire State Building in the 40's in the fog and the building didn't collapse, proves that a plane cannot cause a building to collapse.

This jump in logic must be from a website or LC (I can't remember much from LC anymore). As soon I mentioned the damage and fire he mentioned this. The jump in logic here is that there is some additive property to accident analysis. Fire in 1975 + crop duster flying into the ESB = controlled demolition at WTC.

 

[BadBoy]

And so, NIST, the brightest and the best, charged to investigate the towers for use in improving future building's safety standards, hasn't even a cursory interest in how the building behaved all the way down? No thoughts at all for how they might save anyone in a similar situation in the future who might make it two thirds of the way down and then have a building collapse on them. And you don't find that surprising?

Hay bud, the only person being shamed here is you. I dont post much but you are showing yourself to be a complete idiot. Its the "Dunning Kruger" effect all over again. You cant make something come true by shouting louder or by putting you fingers in your ears and holding your breath. (you can do it duffy moon, you can do it duffy moon....)

I would guess that modelling the collapse would have been far too expensive and probably impossible to do in any timeframe that would give you the detail you seem to be asking for. Way too many variables.

You remind me of an Evolution denier. It dont matter how much evidence you put in the way its just ignored point blank until they get ill tempered.

What a plonker

 

[WildCat]

I'm still waiting to hear what kylebisme's engineering qualifications are.

He's a certified expert in watching low-res truther videos on youtube.

 

[BadBoy]

I was not disregarding any such credentials, but I can't take them as a rational reason to accept the conclusion you are defending either.

It not "their credentials" you are disregarding, its the work of the engineers and scientists with those credentials you are disregarding.

If you could design a structure which fire and distruction from 500 mph airliner collisionwill cause to collapse with a period acceleration indistinguishable from free fall, and consistently demonstrate the ability of your design do so, then I would happily take your conclusion to be a matter of fact. However, since such design would undermine long accepted understandings of the laws of physics, I'm left to disregard your argument here as founded in irrational belief.

I added the bit you missed there.

I'm left to disregard your argument here as founded in irrational belief.

I love this. He's calling you guys irrational. excellent. Pot/kettle/black. Your sliding down a slipery irrational slope I feel. Pulling out weeds as you go, trying to gain some purchase.

I can't rightly expect any of us to be free of irrational beliefs.

Talk for youself, not me.

Given some looking around, I'd bet I could find some structural engineers who believe Copperfield actually did vanish the Statue of Liberty into thin air too

ya, right. Actually, I wonder if Heiwa has a take on the Copperfield incident.

 

[kylebisme]

No, it doesn't look even remotely similar to the Tour Broca verinage. I can't imagine how anyone could think it did.

You don't have to imagine anything to understand, all you'd have to do is recognize the fact that both Tour Broca verinage and Building 7 collapsed with a period of free fall acceleration, both accouting for about 15% of the distance of the fall.

I was quite disgusted that the WTC7 video then repeats the blatant lie that the collapse is symmetrical. Look at it yourself, watch the rotation of the building in the last stages of the collapse, then ask yourself: Why is the person who made this video lying to me?

The roof line is stays fairly symmetrical for a considerable distance of the fall, and to say it feel symmetrically is to speak pf that fact in general terms. To deny that fact in refusal to accept it's implications is a case of straining at a gnat while swallow a camel.

Since the mechanical penthouse had already fallen into the building, I suspect that what was left at that point didn't, in fact, resemble a building very much at all.

It obviously didn't resemble a building very much at, all as evidenced by the free fall acceleration though it. However, the penthouses coming down first does not explain that complete lack of resistive force, and neither does any amount of fire. This is why NIST couldn't show anything of the sort, and neither can anyone else.

Suppose, at some point in the collapse, two levels in the structure proved to be weaker, relative to the forces applied to them, than the rest. Would there be some tendency for the structure to collapse at those two levels preferentially? And, were the section between those two levels to be misaligned from the structure above and below by lateral movements caused by the collapse, so that the columns in the middle section failed to fill the gap between the upper and lower columns, how fast would the top section fall over the height of that section?

They'll bend over and possibly snap in parts, rubbing across other columns and coming down on to beams, all of that is resistive force which would have kept the building from ever archiving free fall acceleration, let alone over 100 feet of it. The throwing a hotdog down a hall scenario you propose isn't rightly applicable here, and again not even NIST could simulate anything of the sort.

Alternatively, suppose that a large mass were falling inside the building - as we are wll aware was happening. Suppose that mass encountered a less seriously damaged section of the internal structure as the main collapse began, and was slowed relative to it. Would the momentum of the falling mass then be transferred to the main structure, hence accelerating the latter structure downwards?

Or, for a third possibility, suppose that, as the main collapse began, the acceleration of the falling penthouse relative to the remainder of the building suddenly reduced (which it would, of course), hence allowing the main structure to arrest the fall of the penthouse relative to it. Again, would this cause a downward acceleration of the main structure in excess of that caused by the resultant of gravitational and resistive force?

In both cases the falling mass will accelerate the part it hits downwards, leaving less force to pull down whatever it might still be attached to above.

Those are just three specific and plausible scenarios in which the acceleration of the building could be close to, or even very slightly greater than, gravitational acceleration for a short part of the collapse.

To achieve downward acceleration in excess of the gravitational and resistive forces involved you'd need something along the line of winches pulling the mass down, or rocket thrusters pushing it that way.

I have yet to see any specific, plausible scenarios as to why the conspirators would want or need to destroy several storeys of the structure, at a specific instant, after the collapse had already begun and its completion was assured; because, once a building that big starts to collapse, it doesn't stop.

I'd ask you to find a building outside of 9/11 which collapsed with a period of free fall acceleration without without destroy several stories of the structure at a specific instant, but knowing it isn't physically possible I wouldn't suggest you waste your time. Put simply, you aren't going to see why this needed to be done until you let go of the false premise by which you dismiss the explanation.

 

[ElMondoHummus]

Dave Rogers can easily handle his own arguments, so I won't respond to the entirety of your post. I'll limit myself to one element that jumps out at me:

However, the penthouses coming down first does not explain that complete lack of resistive force, and neither does any amount of fire. This is why NIST couldn't show anything of the sort, and neither can anyone else.

That is an utterly, completely flawed conclusion. The fact that the penthouses came down first clearly demonstrate that the interior structure was fatally compromised. If the interior was not, how could the penthouses have collapsed to begin with?

You can't argue that the collapse of the penthouses has nothing to do with the severe compromise of interior structural integrity. Their very collapse actually argues the opposite.

 

[kylebisme]

Bet? As in wager? As in if you don't find "some" structural engineers who believe Copperfield actually vanished the statue of liberty, vanished meaning some sort of temporary demolecularization or similar state so as not to appear visible, after looking around you'd give me money?

As in, considering nearly 80 percent of Americans believe in miracles, I'm quite confident that I could find some structural engineers who think Copperfield can produce them. If you want to make it a monetary wager, I'm down as long as it is in accordance with the laws. I'm not interested in your amendment giving you a year to get them fired though.

 

[Myriad]

The throwing a hotdog down a hall scenario you propose...

I don't think the bolded phrase means what you think it means.

At least, given the context, I hope it doesn't.

(Google is your friend!)

To achieve downward acceleration in excess of the gravitational and resistive forces involved you'd need something along the line of winches pulling the mass down, or rocket thrusters pushing it that way.

Instead of winches, how about other structural framework members, that started falling earlier (which some did, as we know from the penthouse collapse), pulling the mass down?

Respectfully,
Myriad

 

[Furcifer]

As in, considering nearly
80 percent of Americans believe in miracles, I'm quite confident that I could find some structural engineers who think Copperfield can produce them. If you want to make it a monetary wager, I'm down as long as it is in accordance with the laws. I'm not interested in your amendment giving you a year to get them fired though.

It' apparent your engaging in faith based observations. I don't think anyone here finds that surprising. That being said I'm in for $50 that says you can't find a structural engineer that will attest to Copperfields mystical powers. I'll email a money order to a neutral party of your choosing from here in the forum. I'd prefer a moderator if willing. A time frame has to be set, I can't have all my assets tied up in this thing. If you win the money is yours, if I win your $50 gets donated to the forum in your name.

You've got until Halloween. No one from your home town or the University you may have attended counts (for obvious reasons. I can get a buddy to swear her saw Nessy). You game or what?

 

[GlennB]

Put simply, you aren't going to see why this needed to be done until you let go of the false premise by which you dismiss the explanation.

Why do you think 'it needed to be done', kyle?

I asked you this before but it's understandable that you missed that post in such a busy thread.

 

[bill smith]

Dave Rogers can easily handle his own arguments, so I won't respond to the entirety of your post. I'll limit myself to one element that jumps out at me:



That is an utterly, completely flawed conclusion. The fact that the penthouses came down first clearly demonstrate that the interior structure was fatally compromised. If the interior was not, how could the penthouses have collapsed to begin with?

You can't argue that the collapse of the penthouses has nothing to do with the severe compromise of interior structural integrity. Their very collapse actually argues the opposite.

But how did this 300-350 ton column 79 cause the rest pf the 40,000 ton steel frame to collapse in such a way that all four corners collapsed st exactly the same time ? They were after all seperated from each other by the entire length and breadth of the building and still all four went down at the same time like mirror images of each other ?