WTC: Rate of Fall (rate of crush)

Mick West

Administrator
Staff member
This is a point I have often raised in other debates... thanks for bringing it up here Lee, as I think it very important.

I also think it very important to note that acceleration due to gravity is only relevant when there is only the normal impedance due to air resistance and cannot be applied where further resistance is encountered.

People keep using this to demonstrate 'how it is mathematically possible for the towers to fall in such a time frame', when this really does not apply at all as the resistance of the supporting structure would significantly impede acceleration from taking place. By what factor seems impossible to conclude as there is no mathematical or evidential data on the resistance.

Yes, that factor is the key here. There's a downwards acceleration of g (gravity), for the buildings to fall as observed, then the net upwards force would have to be around g/10. (Then giving you a downward acceleration of 0.9*g)

There is actually a lot of evidence for the resistance the floors offered. It's been quite well studied. The problem is that the Truthers tend to use either faulty reasoning, or wildly inaccurate estimates (like assuming the fall has to "dustify" everything on the way down, rather than just break the connections). Since the math is beyond most people, you tend to get entrenched positions. There's the basic math here, but even this is still a simplified model (although vastly more accurate than the YouTube whiteboard explanation).

https://www.metabunk.org/files/Why%20Did%20the%20World%20Trade%20Center%20Collapse-Simple%20Analysis.pdf
https://www.metabunk.org/files/Mechanics of Progressive Collapse.pdf
https://www.metabunk.org/files/00 WTC Collapse - What Did & Did Not Cause It.pdf

It think it would be productive to try to get a simpler explanation though.

Long Span flooring sections are in common use and I think it important that people should be assured that the same design faults as allegedly caused wtc1, 2, & 7 to fall, are not inherent in all these other buildings.

I agree, and so does NIST, which is why that was a primary point in their recommendations resulting from the investigations.
I cannot seem to find if the new wtc 7 has long span flooring?
Long span flooring is not inevitably dangerous, it just raises additional issues. The recommendations on NIST are aimed at preventing progressive collapse, not eliminating long span floors.
 
Last edited:

Mick West

Administrator
Staff member
Oh, and the building beams getting thicker and stringer as you get further down is somewhat negated by two facts:

1) The falling mass gets heavier and heavier as it falls, accumulating new floors
2) The vertical girder were not crushed, they were stripped of their floors, and then fell from lack of support (see the buckling video above). This is most clearly demonstrated by the "spire" that remained to half the height of the building before it fell.
 

Mick West

Administrator
Staff member
If the math supports it . . . show me . . . the doubters think the collapse(s) are so reminiscent of a controlled demolition you cannot tell one from the other . . . show me demolitions that collapses in less time . . . ???

The math is in here:
https://www.metabunk.org/files/Why Did the World Trade Center Collapse-Simple Analysis.pdf

Note from there:
That's an important point, they are actually calculating things assuming that all the columns buckle at the collapse front. This scenario gives by far the greatest resistance, and yet it's almost certainly not what happened, it's almost certain that the resistance was a lot lower. And yet even with this overly conservative estimate, the upwards resistance is far less than g.

Like I said though, unfortunately most people don't really understand the math involved, so they can't tell the difference between explanation except by if the result meets their expectations.
 
Last edited:

George B

Extinct but not forgotten Staff Member
You probably can't find a faster collapse . . . they admit as much in your attached cited reference . . . seems just like the simulations of WTC #7 . . . they took what they saw and modeled their assumptions to fit what they thought they saw . . . including their math . . . sorry this does not fly for me Mick!!!!! At least this time they shared their math and data . . . LOL!!!!!!

 
Last edited by a moderator:

Mick West

Administrator
Staff member
You probably can't find a faster collapse . . . they admit as much in your attached cited reference . . . seems just like the simulations of WTC #7 . . . they took what they saw and modeled their assumptions to fit what they thought they saw . . . including their math . . . sorry this does not fly for me Mick!!!!!


Most building implosions happen at about the same speed, although they are a considerably different type of collapse, and nothing like as tall



Verinage demolitions also seem very similar in terms of initial speed, but the examples are much shorter, and the building different in construction, so the fall is arrested quicker:


 
Last edited:

George B

Extinct but not forgotten Staff Member
Yes, Mick and each and every building has been pre-prepared for demolition . . . so we are back to square one if you ask me . . . you try an explanation and I don't think it fits what I witnessed and intuitively understand . . .
 

Mick West

Administrator
Staff member
And as an example of the difficult of providing the "evidence" for which you seek (a similar speed, similar type of collapse). Here's one of the closest, overlaid for scale:



 
Last edited:

Mick West

Administrator
Staff member
Yes, Mick and each and every building has been pre-prepared for demolition . . . so we are back to square one if you ask me . . . you try an explanation and I don't think it fits what I witnessed and intuitively understand . . .

So you are basically saying that unless I can find a 100 story building that accidentally collapsed in the same manner as the WTC, they you are always going to believe it was controlled demolition, because that's your intuition, and you can't follow the math?
 

RolandD

Active Member
Yes, Mick and each and every building has been pre-prepared for demolition . . . so we are back to square one if you ask me . . . you try an explanation and I don't think it fits what I witnessed and intuitively understand . . .

So, what it comes down to is that since it doesn't make sense to you, it can't be true?
 

George B

Extinct but not forgotten Staff Member
So you are basically saying that unless I can find a 100 story building that accidentally collapsed in the same manner as the WTC, they you are always going to believe it was controlled demolition, because that's your intuition, and you can't follow the math?
That is not what I indicated . . . I am saying the math might be correct (however, self fulfilling, insular, finite N) . . . but is based on potential error because they are not using math to prove an outcome of a new event but using math to back engineer (model) what they thought they witnessed . . . forcing the square peg in the round hole as it were . . . I cannot believe you think the building could collapse at nearly the same rate of a bowling ball in a vacuum . . .

Using your own cite as evidence . . .

 
Last edited by a moderator:

George B

Extinct but not forgotten Staff Member
So, what it comes down to is that since it doesn't make sense to you, it can't be true?

I never once said that . . . I am saying it is not adequate evidence to convince me . . . I recognize I am not the judge of the "Truth" . . . far from it . . .
 

George B

Extinct but not forgotten Staff Member
My corrections to your quote below . . . No I am saying you cannot find any building to dissuade me . . . because the building fell at the same rate or faster than a controlled demolition . . . that is not possible in my simple little mind . . . sorry . . .


So you are basically saying that unless I can find a 100 story building that accidentally collapsed in the same manner as the WTC, then you are always going to believe it was controlled demolition . . .
 

Mick West

Administrator
Staff member
That is not what I indicated . . . I am saying the math might be correct (however, self fulfilling, insular, finite N) . . . but is based on error because they are not using math to prove an out come of a new event but using math to back engineer (model) what they though they witnessed . . . forcing the square peg in the round hole as it were . . . I cannot believe you think the building could collapse at nearly the same rate of a bowling ball in a vacuum . . .

Using your own cite as evidence . . .



I don't think that. It think it fell at about 90% the acceleration of free fall. Which is what the cite shows if you had continued that quote:

8.93s vs. "roughly 10", so quite a bit slower than free fall.
 
Last edited:

Mick West

Administrator
Staff member
My corrections below . . . No I am saying you cannot find any building to dissuade me . . . because the building fell at the same rate or faster than a controlled demolition . . . that is not possible in my simple little mind . . . sorry . . .

So you are saying that NOTHING will persuade you short of a full scale replicate being built of the WTC?

Would that even persuade you? Say someone decided to send $200M on such a replica, then destroy it, and it kind of looked like the original WTC, then would you change your mind?

Wouldn't it be a bit simpler for you to just study the math for a while?
 

George B

Extinct but not forgotten Staff Member
So you are saying that NOTHING will persuade you short of a full scale replicate being built of the WTC?

Would that even persuade you? Say someone decided to send $200M on such a replica, then destroy it, and it kind of looked like the original WTC, then would you change your mind?

Wouldn't it be a bit simpler for you to just study the math for a while?
No, as I said (paraphrased) earlier . . . If you can show me a high-rise, steel reinforced, building in a controlled demolition collapsing at a reasonably faster rate than the fastest WTC failure . . . I would then consider the evidence as significant and useful . . . the math is basically only supportive otherwise . . .
 

George B

Extinct but not forgotten Staff Member
Geeeez . . . you are fast Mick . . . new home for the discussion . . . LoL!!
 

Mick West

Administrator
Staff member
No, as I said (paraphrased) earlier . . . If you can show me a high-rise, steel reinforced, building in a controlled demolition collapsing at a reasonably faster rate than the fastest WTC failure . . . I would then consider the evidence as significant and useful . . . the math is basically only supportive otherwise . . .

Do you realize that the fastest possible collapse of a building is free fall, which (using the figures above) is only 1 second quicker than the observed free fall rate for a 110 story building? Do you realize then that for the height of the tallest building that have been demolished (40 stories), then this difference in speed is going to be approximate 0.25 seconds? Would you consider that "reasonably faster"?

The key point here is how much upwards force the building exerts by individual floors (and even columns) resisting collapse. Your intuition says "a lot". But can you put a number on it?

Compare to the verinage demolitions? What does your intuition tell you about them? Don't they also look "too fast"?
 

Mick West

Administrator
Staff member
Another illustration. Here's one estimate of the rate of fall of WTC 1 and WTC2 compared to free falls



I've also added a grey line indicating the height (realtive to the top of the wtc) of the J.L. Hudson department store, one of the highest buildings ever imploded. The yellow line indicates the height of the debris pile, which would be where it stopped falling (although it would have reduced acceleration before that point).

So for an existing building to fall "faster" than WTC2, it would have to be in that region above the yellow line, and between the black free-fall line, and the blue WTC2 line. A barely noticeable difference. And since you discard all the implosions, and Verinage is not tall enough, then you've basically set yourself up to be trapped in a belief.



The only way out is for you to to look at the math.
 
Last edited:

George B

Extinct but not forgotten Staff Member
Have a look at this George, what the first thing in it you either disagree with or don't understand:

http://www.911myths.com/WTCREPORT.pdf

Again . . . the investigator matches reality with his math . . . self-fulfilling re-engineering . . .

 

Mick West

Administrator
Staff member
Again . . . the investigator matches reality with his math . . . self-fulfilling re-engineering . . .


That's not what he's doing. He's nothing an observation, then checking to see if it matches the physics. "place this qualitative prediction on a quantitative basis." means to back up the observation with real figures.

Would you only be satisfied if the person creating the estimate had never heard of the World Trade Center?

Just follow the math. See if he got anything wrong.
 

George B

Extinct but not forgotten Staff Member
Mick said:
then you've basically set yourself up to be trapped in a belief.

If you say so . . . LoL!! I could say look in the mirror . . . you have trapped yourself in believing the official story using the logic . . . if it is a reasonable explanation then accept it . . . mick's Razor . . . .
 

Mick West

Administrator
Staff member
Not incredibly useful as there's no timing, and it's an implosion, but here's a nice photoset of the collapse of a steel framed building:

http://www.flickr.com/photos/55043200@N06/5103126447/in/photostream/

The description of how it was done is interesting though:

http://www.controlled-demolition.com/biltmore-hotel

Imagine if you had to extend that to the size of the WTC, and its considerable more substantial steel.
 

Mick West

Administrator
Staff member
If you say so . . . LoL!! I could say look in the mirror . . . you have trapped yourself in believing the official story using the logic . . . if it is a reasonable explanation then accept it . . . mick's Razor . . . .

I accept it because I see no reason to doubt it. I see no place in which it does not fit the facts. I accept it because it it matches all the math that I can follow.

You doubt it because of your "intuition".
 

George B

Extinct but not forgotten Staff Member
That's not what he's doing. He's nothing an observation, then checking to see if it matches the physics. "place this qualitative prediction on a quantitative basis." means to back up the observation with real figures.

Would you only be satisfied if the person creating the estimate had never heard of the World Trade Center?

Just follow the math. See if he got anything wrong.

Yes, absolutely, completely on the mark . . . bulls eye . . . Bingo!!!!!!!!!!!!!
 

Mick West

Administrator
Staff member
Yes, absolutely, completely on the mark . . . bulls eye . . . Bingo!!!!!!!!!!!!!

It's not like we are testing for PSI ability here George. Nor are we simply taking the work of the person doing the math. You can verify it for yourself.
 

George B

Extinct but not forgotten Staff Member
I accept it because I see no reason to doubt it. I see no place in which it does not fit the facts. I accept it because it it matches all the math that I can follow.

You doubt it because of your "intuition".
I would be lying if I did not say that I find the whole 911 event a bit suspect . . . so I probably require a greater degree of proof to accept the official story . . . gray areas will always be problematic to me . . .
 

George B

Extinct but not forgotten Staff Member
It's not like we are testing for PSI ability here George. Nor are we simply taking the work of the person doing the math. You can verify it for yourself.

Mick, math formulas are only as accurate as the assumptions, the weights and values used in them . . . I am not faulting the physics formulas or math theory, or computations used in them . . . I am saying the assumption that the floor resistance E1 has to be near zero is based upon what?. . . it needs to be (x) to fit what we observed so we will make (were biased by what they thought reality was) the value fit the situation . . . not the other way around . . .
 

Mick West

Administrator
Staff member
Mick, math formulas are only as accurate as the assumptions, the weights and values used in them . . . I am not faulting the physics formulas or math theory, or computations used in them . . . I am saying the assumption that the floor resistance E1 has to be near zero is based upon . . . it needs to be (x) to fit what we observed so we will make (were biased by what they thought reality was) the value fit the situation . . . not the other way around . . .

Eh? Who said it was near zero? It's measured in the billions of newtons, billions of pounds of force.
 

Dan Wilson

Senior Member.
If you say so . . . LoL!! I could say look in the mirror . . . you have trapped yourself in believing the official story using the logic . . . if it is a reasonable explanation then accept it . . . mick's Razor . . . .

Plenty of things in science end up being counterintuitive, doesn't mean it's unlikely or untrue. George, here is a question to consider, what kind force would it take to stop or even delay 15 floors of the WTC after it falls, say, 10 ft.? What amount of "upward force" would it take to stop/slow it? I feel as though that question should be answered if you are to make a case for the collapse not being consistent with physics.
 

George B

Extinct but not forgotten Staff Member
Eh? Who said it was near zero? It's measured in the billions of newtons, billions of pounds of force.

Near zero in its ability to retard the downward crush of the falling block ( I am not totally convinced it was an intact block) based on time to crush . . . not its value in newtons . . .
 

George B

Extinct but not forgotten Staff Member
Plenty of things in science end up being counterintuitive, doesn't mean it's unlikely or untrue. George, here is a question to consider, what kind force would it take to stop or even delay 15 floors of the WTC after it falls, say, 10 ft.? What amount of "upward force" would it take to stop/slow it? I feel as though that question should be answered if you are to make a case for the collapse not being consistent with physics.

It would take an equal or greater resistance than the mass and velocity of the falling mass that hits it (to stop it and less than that to slow it) . . .
 

Dan Wilson

Senior Member.
It would take an equal or greater resistance than the mass and velocity of the falling mass that hits it (to stop it and less than that to slow it) . . .

And what, in numbers, would that be? If you're going to push your case of something being fishy here then that is a crucial piece.
 

George B

Extinct but not forgotten Staff Member
And what, in numbers, would that be? If you're going to push your case of something being fishy here then that is a crucial piece.

Please cut to the chase . . . I can dig out the formulas and put in the estimated values, etc. but I am not a physicists or engineer . . . I have already done it for free fall of objects, terminal velocity accounting for atmospheric resistance at sea level, etc . . . the issue here is can a building, any high-rise steel reinforced building fall at near free fall rates unless it is one that is undergoing a controlled demolition . . .?? All the formulas require weights, estimates, data . . . I am questioning the data, weights and assumptions . . . not the formulae . . .
 

Oxymoron

Banned
Banned
Mick, math formulas are only as accurate as the assumptions, the weights and values used in them . . .

http://en.wikipedia.org/wiki/Black_swan_theory

 

Mick West

Administrator
Staff member
http://en.wikipedia.org/wiki/Black_swan_theory


You mean like how people concoct explanation involving nano-thermite, mini-nukes, or space based energy beams?

Do the math.
 

George B

Extinct but not forgotten Staff Member
You mean like how people concoct explanation involving nano-thermite, mini-nukes, or space based energy beams?

Do the math.

Hmmm . . . you admitted, I believe, yourself the events were unprecedented . . . the explanations; therefore, require a higher standard of scrutiny . . . I see no problem with that . . . I don't have a reasonable explanation, but that does not mean there isn't one . . .
 

Dan Wilson

Senior Member.
Please cut to the chase . . . I can dig out the formulas and put in the estimated values, etc. but I am not a physicists or engineer . . . I have already done it for free fall of objects, terminal velocity accounting for atmospheric resistance at sea level, etc . . . the issue here is can a building, any high-rise steel reinforced building fall at near free fall rates unless it is one that is undergoing a controlled demolition . . .?? All the formulas require weights, estimates, data . . . I am questioning the data, weights and assumptions . . . not the formulae . . .

And is my question not essential to the issue? It would be nice if you did dig out the formulae, you can't go off intuition and what you think is the right answer. Mick has put together a strong case here, you don't need to be an engineer or physicist to get a grasp of this stuff. If you're going to make the case you might as well do the math.
 

Mick West

Administrator
Staff member
Hmmm . . . you admitted, I believe, yourself the events were unprecedented . . . the explanations; therefore, require a higher standard of scrutiny . . . I see no problem with that . . . I don't have a reasonable explanation, but that does not mean there isn't one . . .

Well, so why are you not scrutinizing the explanations? Why just rely on your intuition, which is known to be fallible, and has been thrown by the scale of the buildings.
 
Thread starter Related Articles Forum Replies Date
P Need Debunking: "Experimental Vaccine Death Rate for Israel's Elderly 40 Times Higher Than COVID-19 Deaths" Coronavirus COVID-19 7
Mick West Debunked: "Error rate of 68.5% Allowable is .0008%" [Neither is True] Election 2020 4
DavidB66 Wuhan Funeral Urns as an Indicator of Death Rate? Coronavirus COVID-19 31
Rory Debunked: The Lunar Cycle affects birth rates Health and Quackery 33
letrec Kinematic production of molten steel and its cooling rate 9/11 42
Mick West Debunked: "There are many ways to make the death rate increase." - Robert McNamara Quotes Debunked 0
Nandude Light Fall Off in Apollo Missions - American Moon Documentary Conspiracy Theories 16
McGurnicle Why some people fall down the rabbit hole Escaping The Rabbit Hole 28
Mick West How Buckling Led to "Free Fall" acceleration for part of WTC7's Collapse. 9/11 129
Mackdog Court Rules Negligence Didn’t Cause World Trade Center 7 To Fall On 9/11 9/11 103
Mick West Paraody of AE911: Free-fall descent proves giant hole, not explosives used! 9/11 62
SR1419 New Poll: Conspiracy Beliefs Fall Along Party Lines General Discussion 0
Mick West Debunked: Strange Blue Spheres Fall Over England 2012 Ghosts, Monsters, and the Paranormal 15
Mick West Debunked: Chemwebs / Mysterious Fibers fall from sky (ballooning spiders) Contrails and Chemtrails 75
Jay Reynolds Web Fall Arkansas 2006 Contrails and Chemtrails 6
Mick West Dead Blackbirds Fall From Sky, Prompting Bunk General Discussion 14

Related Articles

Top