If "partial collapse" is POSSIBLE why is "complete collapse" IMPOSSIBLE?

[LastChild]

Are you really claiming that the upper block turned into fine particles and trickled slowly down on the lower part of the WTC? Really?

I don't know was lapman claiming an SUV was dropped on the WTC?

And this, ladies and gentlemen, is all that's left of the truth movement!

And that's why you come here everyday?

 

[JHarrow]

Here are the calculations you wanted.

x = 20 (upper portion, in motion)
y = 90 (lower portion, in motion)

Assume that the mass of 20 floors is enough to collapse ONE floor at near free fall speeds.

After one floor collapses:

20 + 1 = 21
90 - 1 = 89

x = 21
y = 89

If 20 floors is sufficient to collapse one floor at near free fall speeds, then 21 floors is also sufficient to collapse one floor at near free fall speeds.

After two floor collapse:

21 + 1= 22
89 - 1 = 88

x = 22
y = 88

If 21 floors is sufficient to collapse one floor at near free fall speeds, then 22 floors is also sufficient to collapse one floor at near free fall speeds.

Do you see the pattern here?

If you continue with these equations, you will find that y (the number of floors that have not yet collapsed) will eventually reach zero. This means that what starts out as 20 floors grows in size until it encompasses the whole building.

If you doubt that 20 floors can collapse one floor at near free-fall speeds, then you phrased your question oddly. It should have been:



But, of course, that would have lacked the rhetorical impact. As we all know, the troof is about rhetoric, not logic or mathematics.

I don't see any consideration of the 47 huge core columns in your calculations. Please revise them and get back to me.

 

[LastChild]

double

 

[chillzero]

This thread seems to be straying from the topic once more. Please get it back on track, or it will be set to moderated status.

Replying to this modbox in thread will be off topic  Posted By: chillzero

 

[R.Mackey]

I believe you have a debate with Mr. Mackey. You two seem to disagree on this point.

No. There is no disagreement. The situation Garrette is describing is one of slow energy dissipation. That's another way you can reduce impact stress. If you dump all the sand at once, and it all hits the target, the impulse delivered is the same.

Insinuating there was nothing but air in-between and virtually no resistance offered all the way down is paying attention? Do you see the emperor’s new cloths too? Is it pretty?

The only one here stating that there was "virtually no resistance" is you. An energy calculation based on a 12-second collapse time reveals that half of the energy, roughly, was dissipated -- the lower structure resisted with an average power of approximately 20 GW. That's not "virtually no resistance." See Appendix B of my whitepaper.

As a result, the logic goes like this:

• Fire can cause local collapse of structures
• Local collapse of structures can cause global collapse of structures (see Bazant, etc.)
• Therefore, fire can cause global collapse of structures

... and the OP is confirmed.

 

[Garrette]

I believe you have a debate with Mr. Mackey. You two seem to disagree on this point.

More evidence you're not reading well. I said the sand needed to have the same footprint as the boulder. R. Mackey said your head needs to be wide enough to catch all the sand. Different method of reaching the same point to illustrate the same fallacy in your analogy.

No. I didn't bring up the dropping of a suspended SUV .

So you intentionally misread things, I take it. I said you brought up "raised up" as in raising up the floors. You did. I didn't mention SUVs.

At what point did it become not intact?

No idea. It makes no difference whether it is intact or in a broken pile as it falls. The dynamic force remains sufficient to collapse the next floor, regardless is some of the stuff falls out the sides, but even that--as has been pointed out--occurred mostly below the impacts.

It wasn't still there when the collapse was complete was it? What caused it to become not intact and at what point?

Ah. So you're a fan of dustification or some other mechanism of breaking the structure of the building down. Because if you're proposing a controlled demo then you'll have to ask the same question, and when you can answer that question for a controlled demo, then you'll understand why it's a stupid question here.

Insinuating there was nothing but air in-between

When the supporting structure stops supporting, then it is virtually nothing but air in-between. And by "virtually nothing" I mean nothing that increases the ability of the still intact floor to arrest the drop of the falling structure.

and virtually no resistance offered all the way down is paying attention?

If by "virtually non resistance" you mean a lot of resistance but far far short of what was required to arrest the drop of the falling structure, then yes that would be paying attention.

Do you see the emperor’s new cloths too? Is it pretty?

Emperor = Truth Movement

Emperor's Clothes = Truth Movement Evidence

So no, I don't see the emperor's new clothes, but I do see the emperor, and he's quite naked.

 

[Garrette]

In accord with ChillZero's request (and the OP), I will refrain from posting again here unless it is to remind Truthers of the unanswered question:

Given that fires can cause partial collapse of a building, why can't fires cause total collapse of a building?

 

[LastChild]

No. There is no disagreement. The situation Garrette is describing is one of slow energy dissipation. That's another way you can reduce impact stress. If you dump all the sand at once, and it all hits the target, the impulse delivered is the same.

No. If you dropped a bag of cement on your head you might be killed depending on where it was dropped from. If you dropped an open bag of cement the impact would be less.

If you stacked 20 bags of cement on top of each other and ripped open the 17th bag up the 3 above it might eventually fall. Probably over the side if at all but never straight through the lower 16.

The only one here stating that there was "virtually no resistance" is you. An energy calculation based on a 12-second collapse time reveals that half of the energy, roughly, was dissipated -- the lower structure resisted with an average power of approximately 20 GW. That's not "virtually no resistance." See Appendix B of my whitepaper.

As a result, the logic goes like this:

• Fire can cause local collapse of structures
• Local collapse of structures can cause global collapse of structures (see Bazant, etc.)
• Therefore, fire can cause global collapse of structures

... and the OP is confirmed.

Then model it. Or show an example other then 9/11 where it supposedly happened 3 times in one day but never before and never since and never again.

 

[LastChild]

Emperor = Truth Movement

Emperor's Clothes = Truth Movement Evidence

So no, I don't see the emperor's new clothes, but I do see the emperor, and he's quite naked.

Emperor = Government

Emperor's Clothes = The NIST report and The 9/11 commission report.

The Emperor is parading naked in the street with his Nistians cheering him on.

 

[chillzero]

LastChild,
Given that fires can cause partial collapse of a building, why can't fires cause total collapse of a building?

 

[JHarrow]

LastChild,
Given that fires can cause partial collapse of a building, why can't fires cause total collapse of a building?

Why does it follow?

There are no examples of complete collapse of tall buildings due to fire, except on 911.

Partial collapse are to be expected in certain types of building. Total collapses have never occured.

 

[Garb]

Emperor = Government

Emperor's Clothes = The NIST report and The 9/11 commission report.

The Emperor is parading naked in the street with his Nistians cheering him on.

Are you trying to say that the NIST and 9/11 commission report don't exist here?

Your analogy doesn't make any sense.

 

[chillzero]

Why does it follow?

There are no examples of complete collapse of tall buildings due to fire, except on 911.

Partial collapse are to be expected in certain types of building. Total collapses have never occured.

Just trying to drag everyone back to the topic at hand.

I don't understand why anyone has an issue with this anyway - it's all a matter of degrees. Partial collapse can be anything from 1% to 99.something%. Personally, I am certain that there was not 100% total collapse of the towers anyway, given what I have seen of the rubble, and the fact that a staircase and part of the central support survived.

In that respect I would agree with you - total collapse has probably never occurred.

 

[R.Mackey]

No. If you dropped a bag of cement on your head you might be killed depending on where it was dropped from. If you dropped an open bag of cement the impact would be less.

This is false. Take a physics class.

The only exception would be if a container was used to limit wake dissipation in an impacting fluid. At normal velocities, solids do not behave like fluids, and thus this mechanism does not apply.

Again, I implore you to look up "Dead Blow Hammer." This will illustrate quite nicely the effect being discussed.

If you stacked 20 bags of cement on top of each other and ripped open the 17th bag up the 3 above it might eventually fall. Probably over the side if at all but never straight through the lower 16.

I fail to see any relevance to this contrived example.

Then model it. Or show an example other then 9/11 where it supposedly happened 3 times in one day but never before and never since and never again.

It's been modeled. See Bazant & Zhou, Greening, BLBG, Seffen. You've been shown these before. Your inability to follow through is your problem.

 

[JHarrow]

Just trying to drag everyone back to the topic at hand.

I don't understand why anyone has an issue with this anyway - it's all a matter of degrees. Partial collapse can be anything from 1% to 99.something%. Personally, I am certain that there was not 100% total collapse of the towers anyway, given what I have seen of the rubble, and the fact that a staircase and part of the central support survived.

In that respect I would agree with you - total collapse has probably never occurred.

You cant see a difference between fire collapsing a small steel portion of the windsor tower (After hours of burning) and fire destroyong TWO 110 storey buildings pretty much completely, after only 1 or 2 hours?

 

[Garrette]

Why does it follow?

Why does it not, and where is the cut off?

What is the limit of damage that fires can cause? How have you determined that limit? Where is the model? The calculations?

Yes. So it's happened.

Or are you like LastChild: Nothing can ever happen because nothing can ever happen without precedent? That is where your logic leads. It only stands up if you consciously look at one aspect of the scenario and not others.

Total collapses have never occured.

They have. Three times (unless you accept ChillZero's observation that the WTC collapses weren't total.

 

[Garrette]

You cant see a difference between fire collapsing a small steel portion of the windsor tower (After hours of burning) and fire destroyong TWO 110 storey buildings pretty much completely, after only 1 or 2 hours?

If a fire can cause partial collapse of a building, why can't it cause total collapse of a building?

 

[JHarrow]

If a fire can cause partial collapse of a building, why can't it cause total collapse of a building?

It is up to the official story defenders to show it could.

It doesn't follow that because a few steel members failed in a fire then all 47 core columns in wtc would fail and completely destroy the building.

If complete collapse was so rational and logical why would 300 firefighters go into the towers? They did not think those towers would collapse, why is that?

 

[lapman]

You cant see a difference between fire collapsing a small steel portion of the windsor tower (After hours of burning) and fire destroyong TWO 110 storey buildings pretty much completely, after only 1 or 2 hours?

You can't see the difference between the steel portions of the Windsor tower collapsing SOLELY due to fire and the towers collapsing due to fire AND EXTENSIVE STRUCTURAL DAMAGE. Why do you keep taking the damage out of the equation?

 

[LastChild]

LastChild,
Given that fires can cause partial collapse of a building, why can't fires cause total collapse of a building?

chillzero,

What pecentage of say WTC1 would you say was on fire? (And we're not talking about the foundation are we?)

What percentage of WTC1 would you say suffered collapse?