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aquatus1

The Line

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The NIST pins down the science of the 9/11 collapses precisely.

"The focus of the Investigation was on the sequence of events from the instant of aircraft impact to the initiation of collapse for each tower. For brevity in this report, this sequence is referred to as the "probable collapse sequence," although it includes little analysis of the structural behavior of the tower after the conditions for collapse initiation were reached and collapse became inevitable."

the quote is written by NIST:

http://www.nist.gov/el/disasterstudies/wtc/wtc_about.cfm

as soon as that top block began to move downwards, NIST stopped their analysis and went home. aquatus won't point to the nist report because aquatus can't point to the nist report. he can't because its not in the report!

all they gave us was "collapse became inevitable", that's not "pinning down" the science, and its certainly not science.

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Posted (edited)

There's nothing wrong with discussing the science behind the NIST report, it's just a different angle of discussion. That's why aquatus suggested another thread for that discussion.

Heck, not even that. Yamato is perfectly free to discuss the science of the NIST report. I welcome it, even though I wouldn't join in, as I have my own discussion going.

The only thing is that it has to be the science of the report, not who it came from, or the agency that produced it, or the credibility of the producers, none of that is science. What is in the actual report, the calculations, the derivations, the conclusions, the analysis, that is science. That's the stuff that tends to be so complex that most people shy away from it.

The purpose of this thread is to discuss precisely that complex science, and to break it down enough so that one can follow it along a bit more easily, if not fully achieve an understanding on it. Right now, I am focusing on the collapse, because it happens to be interesting to me now. If Yamato wants to begin a discussion about the science in the study, great, feel free. There's plenty of room to discuss more than one topic.

What I don't want is for this to become yet another "Feh! Thaaat report was done by NISTTTTTT! Everyone knows they were paid off by the government!"...and to a lesser extent, "...barely-relevant error-riddled hobbyist analyses or politically-charged backyard experiments with a political agenda.", but I do admit to being biased, as some of those videos are so utterly deficient as to be intentionally misleading. All I'm saying is I don't want people to focus on the experimenter. I want people to focus on the experiment.

Edited by aquatus1

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Posted (edited)

Just when you thought it was safe to go back in the water...

At about 1.3 seconds after initiation, floors 10/9 impacted floor 8, and the resulting floor 10/9/8 was set to continue on its journey.

When suddenly, out of nowhere, floor 11 attacks with all the ferocity a 200 kg slab that has plumetted for 9 meters can muster!

  • Solving for velocity(v): mgh (PE) = 1/2mv2 (KE); v = 13.28 m/s, time(t) = 1.35 s

Floor 11 finally catches up to floor 10/9/8, as it didn't have anything slowing its descent.
Note f
11
has a higher velocity than f
10
did due to its greater initial height.
  • Solving for Impact Force(Favg): distance(d) = 1/2mv2; Favg = 70,543 N

  • Solving for Elastic: final velocity(v'1) = ((m1 - m2)/(m1 + m2))v1; v'2 = (2m1/(m1 + m2))v1
  • m1 = 100 kg, v1 = 13.28 m/s
  • m2 = 620 kg, v2 = 5.14 m/s
  • v1' = -0.73 m/s, v2' = 7.4 m/s

The impact calculation has to include the current downward velocity of f
10/9/8
.
  • Calculating loss of mass: 2 blocks(b') = 20% of original mass per slab per impact
  • loss = 2 b11; 2(20 kg) = 40 kg
  • m' = m1 + m2 - loss
  • m' = 680 kg, v2' = 7.4 m/s

Since only F11 is doing the impacting, we will only remove the mass from it. Even though this v
1
is more than 3 times smaller than the v
1
that jettisoned F
10
's identical blocks, we'll just go ahead and pretend that this smaller force is just as powerful, despite the opposite being true in the real world.
  • Solving for Inelastic: v' = (m1/(m1 + m2))v1
  • m1 = 100 kg, v1 = 13.28 m/s
  • m2 = 620 kg
  • m'= 720 kg, v' = 1.84 m/s

This is interesting here!
Notice how in an Inelastic collision, the energy from that high velocity is almost entirely lost, even though the mass is increased. What is this going to mean to the average force of the mass as a whole?
  • Conservation of Momentum:
  • initial momentum(p): m1v1 + m2v2 = (m1 + m2)v'; final momentum(p') = m1v1' + m2v2'
  • m1 = 680 kg, v1 = 7.4 m/s
  • m2 = 720 kg, v2 = 1.84 m/s
  • v1' = ? m/s, v2' = ? m/s

  • v1' = 4.55 m/s, v2' = 4.55 m/s
  • m'= 1400 kg, v' = 4.55 m/s

Whoa! What happened there? Is our avalanche going slower? After being hit from above by a high velocity mass? Physics, why hast thou forsaken me!?!

Again, this is one of those things that we intuitively feel is wrong. Something is falling, you hit it from above, so it should fall faster, right? Well...not always.

The trick is to go back and remember that our net force, our Favg = ma. The velocity of floor 11 may have been high, but the mass was low compared to the mass of floors 10/9/8. At impact, that velocity had to be averaged out among the mass as a whole (conservation of momentum). As Newton's 1st law tells us, the inertia is directly proportional to the magnitude of the mass. Since the mass of floor 11 suddenly increase drastically when it became floor 11/10/9/8, more energy was required to accelerate it, and when the energy it previously had from the fall wasn't enough, it had to borrow some from the velocity floor 10/9/8 had prior to impact.

Think of it like a football player running down the field and getting hit from behind by a flying tackle from a smaller player. While the impact velocity is high, the large football player can absorb the hit without too much problem, but the longer the tenacious little footballer hangs on, the more his added mass works to slow down the big footballer. Similarly, our new avalanche, designated F11/10/9/8 has to pull its now bigger bulk, and the increased inertia from the increased mass means that it will take a bit more time to do it. Fortunately, gravity is still on and willing to help out.

Edited by aquatus1

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I agree it is getting bogged down. but if you invoke physics you need to be explicit and use the correct terms, one might be well intentioned but using incorrect terms leads to confusion.

"The 9/11 collapses happened exactly how I would expect them to happen 99 times out of 100 if they were repeated 100 times."

such a thing has never happened before, you have no reference point, so how do you claim it is what you expected?

the top block of wtc1 accelerates down through the building, there is no deceleration, which is inconsistent with newtons laws. the verinage demolition (most similar experiment) show the deceleration, the wtc do not (and you can't pick it up just by eye).

[media=]

[/media]

studies have been done. but what you are not factoring is the reaction to the actions of those studies. they are simply dismissed as "conspiracy throrists". top-shelf? what "top-shelf" journal would touch such a thing? the journal process of rejecting a paper is as simple as "no", proving that political expediency is a stronger force than scientific enquiry.

You give me a video of Jonathan Cole talking about fundamental laws of falling objects (exactly what we've been limited to on this thread incidentally) to counter over 200 specialists, over 1000 interviews and tens of thousands of pages of analysis specific to the WTC collapses?

What top engineering university in the US wouldn't refute the NIST report immediately if these conspiracy theories were sound, and moreover, why wouldn't they? Forget political expediency. We've had over 11 years for currently employed professors at any top university to research a serious challenge to the NIST report, or any PhD grads producing such dissertations. That's how you cut the political expediency out of this event, because the best universities are not willing to damage their reputations by handing doctorates out to people who don't earn them. That's what garners a quick "no"; scientific validity is what garners a "yes" and this wouldn't take anywhere near the almost 12 years we've had to be discussing them right now if they were out there.

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Posted (edited)

as soon as that top block began to move downwards, NIST stopped their analysis and went home.

Not science.

aquatus won't point to the nist report because aquatus can't point to the nist report. he can't because its not in the report!

Actually, the answer to that is precisely why I chose to talk about the energy involved in a progressive collapse. Ideally, by the end of this example, people will be able to see why the above isn't really a mystery.

all they gave us was "collapse became inevitable", that's not "pinning down" the science, and its certainly not science.

But then, it has been conclusively shown that you do not have the ability to determine what is the purpose of a scientific analysis or experiment, and as such, a conclusion like that is highly suspect.

You give me a video of Jonathan Cole talking about fundamental laws of falling objects (exactly what we've been limited to on this thread incidentally) to counter over 200 specialists, over 1000 interviews and tens of thousands of pages of analysis specific to the WTC collapses?

Not science, but it is logic and critical thinking, so :tu:

What top engineering university in the US wouldn't refute the NIST report immediately if these conspiracy theories were sound, and moreover, why wouldn't they? Forget political expediency. We've had over 11 years for currently employed professors at any top university to research a serious challenge to the NIST report, or any PhD grads producing such dissertations. That's how you cut the political expediency out of this event, because the best universities are not willing to damage their reputations by handing doctorates out to people who don't earn them. That's what garners a quick "no"; scientific validity is what garners a "yes" and this wouldn't take anywhere near the almost 12 years we've had to be discussing them right now if they were out there.

That's...not so much critical thinking anymore, as it is common sense. However, being that common sense has been shown to not be that common among the CT community, perhaps you could detail it out a bit more? Maybe some examples and such?

Basically, as if some kid new to the internet somehow wandered in here and was hearing this for the first time. Ideally, we want to set him up with all the tools he might need to prevent himself from being misled by nonsense like that video.

Edited by aquatus1

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Heck, not even that. Yamato is perfectly free to discuss the science of the NIST report. I welcome it, even though I wouldn't join in, as I have my own discussion going.

The only thing is that it has to be the science of the report, not who it came from, or the agency that produced it, or the credibility of the producers, none of that is science. What is in the actual report, the calculations, the derivations, the conclusions, the analysis, that is science. That's the stuff that tends to be so complex that most people shy away from it.

The purpose of this thread is to discuss precisely that complex science, and to break it down enough so that one can follow it along a bit more easily, if not fully achieve an understanding on it. Right now, I am focusing on the collapse, because it happens to be interesting to me now. If Yamato wants to begin a discussion about the science in the study, great, feel free. There's plenty of room to discuss more than one topic.

What I don't want is for this to become yet another "Feh! Thaaat report was done by NISTTTTTT! Everyone knows they where paid off by the government!"...and to a lesser extent, "...barely-relevant error-riddled hobbyist analyses or politically-charged backyard experiments with a political agenda.", but I do admit to being biased, as some of those videos are so utterly deficient as to be intentionally misleading. All I'm saying is I don't want people to focus on the experimenter. I want people to focus on the experiment.

Of course! That is the actual science of the situation here. So why did you respond with "This isn't a thread about who is in the pocket of whomever the current nebulous meanie controlling the world is. If you can't pin down the science to be discussed, then you aren't discussing a science."

"Everyone knows they were paid off by government." And that's the kind of conspiratorial thinking we've heard how many times before on this one website alone? If we can't rely on the institutions that independently collaborated the NIST report, and I have no reason to believe that's the case, then why can't we find ANYONE from the top 10 engineering schools of this country who aren't paid off by the government to say otherwise? I don't want to bury my nose in arbitrary math problems assuming floating floors without cores or any consideration to the materials under the influence of the physical laws much less any of the variables in the impact/fire leading to the collapse so it's not the "actual science", it's an archaic physics problem out of a college textbook calculating force which becomes tremendous as you near the ground. I get that. Will there be a single conspiracy theorist convinced to change their mind by that exercise?

It doesn't even have to be the NIST report. If there is no authoritative study published where I can read about these amazing conspiracies in leading scientific journals, why isn't there? Was all of academia paid off by the Bush administration too, to keep his secret to accomplish whatever, forever? Let's be frank here. If there weren't any conspiracy theories about this event, this thread wouldn't even exist.

http://grad-schools.usnews.rankingsandreviews.com/best-graduate-schools/top-engineering-schools/eng-rankings

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Yamato, what you're talking about is a valid subject that involves the scientific investigation of the complete event . What aquatus is talking about is talking about is the science, the physics on a quantum level, of the collapse. They are two different discussions.

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Posted (edited)

Okay, now things get a little boring for the next few floors. I'll go ahead and present the data, and if anyone has any questions, I'll be more than happy to explain.

F11/10/9/8 impacts F9:

  • Solving for velocity(v):
  • v1 = 4.55 m/s, d = 3 m, a = 9.82 m/s2

  • v' = 8.93 m/s, t = .44 s

  • Solving for Impact Force(Favg): distance(d) = 1/2mv2; Favg = 223,285 N vs f7 = 15,680 N

  • Solving for Elastic: final velocity(v'1) = ((m1 - m2)/(m1 + m2))v1; v'2 = (2m1/(m1 + m2))v1
  • m1 = 700 kg, v1 = 8.93 m/s
  • m2 = 800 kg, v2 = 0 m/s
  • v1' = -0.5 m/s, v2' = 8.33 m/s

  • Calculating loss of mass: 2 blocks(b') = 20% of original mass of slab = per impact
  • loss = 2b11 + 2 b10 + 2 b9+ 2 b8 + 2b7; 2(20 kg) + 2(20 kg) + 2(40 kg) + 2(80 kg) = 320 kg
  • m' = m1 + m2 - loss
  • m' = 2720 kg, v2' = 5.86 m/s

  • Solving for Inelastic: v' = (m1/(m1 + m2))v1
  • m1 = 700kg, v1 = 8.93 m/s
  • m2 = 800 kg
  • m'= 1600 kg, v' = 4.13 m/s

  • Conservation of Momentum:
  • initial momentum(p): m1v1 + m2v2 = (m1 + m2)v'; final momentum(p') = m1v1' + m2v2'
  • m1 = 1120 kg, v1 = 8.33 m/s
  • m2 = 1600 kg, v2 = 4.13 m/s
  • v1' = ? m/s, v2' = ? m/s

:
  • v1' = 5.86 m/s, v2' = 5.86 m/s
  • m'= 2720 kg, v' = 5.86 m/s

Take-away:

  • f11/10/9/8/7 has a final mass of 2720 kg and a final velocity of 5.86 m/s,
  • Favg = 223,285 N vs f7 = 15,680 N,
  • Floor 7 had the upward force to support 4 floors; Now, it has a downward force equal to 14 sets of 4 floors.

Edited by aquatus1

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Because he (aquatus) is trying to focus in on specific physics involved the dynamics of collapse.

There's nothing wrong with discussing the science behind the NIST report, it's just a different angle of discussion. That's why aquatus suggested another thread for that discussion.

NIST has addressed the 9/11 collapse including what he's not addressing pointed out in how much back and forth with other posters on this thread already? That's why I weighed in. This is important to consider after his detractors have already pointed out that he's assuming floors floating in midair, and they're right. He's overselling us on what he's doing with "actual science" but it cannot translate to the 9/11 collapse because it's inconsiderate of 9/11's variables. I will agree to "I'm running values I made up with simplifications I made up using formulas I looked up in a physics textbook."

1. Was there enough gravitational energy present in the World Trade Center Towers to cause the collapse of the intact floors below the impact floors? Why was the collapse of WTC 1 and 2 not arrested by the intact structure below the floors where columns first began to buckle?

Yes, there was more than enough gravitational load to cause the collapse of the floors below the level of collapse initiation in both WTC Towers. The vertical capacity of the connections supporting an intact floor below the level of collapse was adequate to carry the load of 11 additional floors if the load was applied gradually and 6 additional floors if the load was applied suddenly (as was the case). Since the number of floors above the approximate floor of collapse initiation exceeded six in each WTC Tower (12 and 29 floors, respectively), the floors below the level of collapse initiation were unable to resist the suddenly applied gravitational load from the upper floors of the buildings. Details of this finding are provided below:

Consider a typical floor immediately below the level of collapse initiation and conservatively assume that the floor is still supported on all columns (i.e., the columns below the intact floor did not buckle or peel-off due to the failure of the columns above). Consider further the truss seat connections between the primary floor trusses and the exterior wall columns or core columns. The individual connection capacities ranged from 94,000 lb to 395,000 lb, with a total vertical load capacity for the connections on a typical floor of 29,000,000 lb (See Section 5.2.4 of NIST NCSTAR 1-6C). The total floor area outside the core was approximately 31,000 ft2, and the average load on a floor under service conditions on September 11, 2001 was 80 lb/ft2. Thus, the total vertical load on a floor outside the core can be estimated by multiplying the floor area (31,000 ft2) by the gravitational load (80 lb/ft2), which yields 2,500,000 lb (this is a conservative load estimate since it ignores the weight contribution of the heavier mechanical floors at the top of each WTC Tower). By dividing the total vertical connection capacity (29,000,000 lb) of a floor by the total vertical load applied to the connections (2,500,000 lb), the number of floors that can be supported by an intact floor is calculated to be a total of 12 floors or 11 additional floors.

This simplified and conservative analysis indicates that the floor connections could have carried only a maximum of about 11 additional floors if the load from these floors were applied statically. Even this number is (conservatively) high, since the load from above the collapsing floor is being applied suddenly. Since the dynamic amplification factor for a suddenly applied load is 2, an intact floor below the level of collapse initiation could not have supported more than six floors. Since the number of floors above the level where the collapse initiated, exceeded 6 for both towers (12 for WTC 1 and 29 for WTC 2), neither tower could have arrested the progression of collapse once collapse initiated. In reality, the highest intact floor was about three (WTC 2) to six (WTC 1) floors below the level of collapse initiation. Thus, more than the 12 to 29 floors reported above actually loaded the intact floor suddenly.

2. Were the basic principles of conservation of momentum and energy satisfied in NIST’s analysis of the structural response of the towers to the aircraft impact and the fires?

Yes. The basic principles of conservation of momentum and conservation of energy were satisfied in these analyses.

In the case of the aircraft impact analyses, which involved a moving aircraft (velocity) and an initially stationary building, the analysis did, indeed, account for conservation of momentum and energy (kinetic energy, strain energy).

After each tower had finished oscillating from the aircraft impact, the subsequent degradation of the structure involved only minute (essentially zero) velocities. Thus, a static analysis of the structural response and collapse initiation was appropriate. Since the velocities were zero and since momentum is equal to mass times velocity, the momentum terms also equaled zero and therefore dropped out of the governing equations. The analyses accounted for conservation of energy.

http://www.nist.gov/public_affairs/factsheet/faqs12007.cfm

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F11/10/9/8/7 impacts F6:

  • Solving for velocity(v):
  • v1 = 5.86 m/s, d = 3 m, a = 9.82 m/s2

  • v' = 9.66 m/s, t = .38 s

  • Solving for Impact Force(Favg): distance(d) = 1/2mv2; Favg = 507,636 N vs f6 = 31,360 N

  • Solving for Elastic: final velocity(v'1) = ((m1 - m2)/(m1 + m2))v1; v'2 = (2m1/(m1 + m2))v1
  • m1 = 1360 kg, v1 = 9.66 m/s
  • m2 = 1600 kg, v2 = 0 m/s
  • v1' = -0.78 m/s, v2' = 8.87 m/s

  • Calculating loss of mass: 2 blocks(b') = 20% of original mass of slab = per impact
  • loss = 2b11 + 2 b10 + 2 b9+ 2 b8 + 2b7; 2(20 kg) + 2(20 kg) + 2(40 kg) + 2(80 kg) + 2(160) = 640 kg
  • m' = m1 + m2 - loss
  • m' = 2320 kg, v2' = 8.87 m/s

  • Solving for Inelastic: v' = (m1/(m1 + m2))v1
  • m1 = 1360kg, v1 = 9.66 m/s
  • m2 = 1600 kg
  • m'= 2960 kg, v' = 4.43 m/s

  • Conservation of Momentum:
  • initial momentum(p): m1v1 + m2v2 = (m1 + m2)v'; final momentum(p') = m1v1' + m2v2'
  • m1 = 2320 kg, v1 = 8.87 m/s
  • m2 = 2960 kg, v2 = 4.43 m/s
  • v1' = ? m/s, v2' = ? m/s

:
  • v1' = 6.38 m/s, v2' = 6.38 m/s
  • m'= 5230 kg, v' = 6.38 m/s

Take-away:

  • f11/10/9/8/7/6 has a final mass of 5230 kg and a final velocity of 6.38 m/s,
  • Favg = 507,636 N vs f7 = 31,360 N,
  • Floor 6 had the upward force to support 5 floors; Now, it has a downward force equal to 16 sets of 5 floors.

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NIST has addressed the 9/11 collapse including what he's not addressing pointed out in how much back and forth with other posters on this thread already?

So what? As I have stated 7 times at this point, I am not talking about the collapse of the WTC towers themselves.

That's why I weighed in. This is important to consider after his detractors have already pointed out that he's assuming floors floating in midair, and they're right.

Being right about something that was stated, re-stated, and over-stated, to be intentional isn't much of an accomplishment.

He's overselling us on what he's doing with "actual science"

Overselling? :unsure:

Are you serious?

...but it cannot translate to the 9/11 collapse because it's inconsiderate of 9/11's variables.

Yamato...

Have you read ANY of my posts? about what I'm doing?

I will agree to "I'm running values I made up with simplifications I made up using formulas I looked up in a physics textbook."

...okay, good, so you did at least read the posts where I said pretty much the same thing, only with a hell of a lot more emphasis.

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Yamato, what you're talking about is a valid subject that involves the scientific investigation of the complete event . What aquatus is talking about is talking about is the science, the physics on a quantum level, of the collapse. They are two different discussions.

The collapse of the WTC is the event, Lilly. He can't refute 9/11 conspiracy theory unless the discussion is about the 9/11 collapse. We note the subject "Reasonable doubt vs. Fallacy of Incredulity".

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So what? As I have stated 7 times at this point, I am not talking about the collapse of the WTC towers themselves.

So your chance of refuting 9/11 conspiracy theory is zero.

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F11/10/9/8/7/6 impacts F5:

  • Solving for velocity(v):
  • v1 = 6.38 m/s, d = 3 m, a = 9.82 m/s2

  • v' = 9.98 m/s, t = .36 s

  • Solving for Impact Force(Favg): distance(d) = 1/2mv2; Favg = 1,041,820 N vs f6 = 62,720 N

  • Solving for Elastic: final velocity(v'1) = ((m1 - m2)/(m1 + m2))v1; v'2 = (2m1/(m1 + m2))v1
  • m1 = 2615 kg, v1 = 9.98 m/s
  • m2 = 3200 kg, v2 = 0 m/s
  • v1' = -0.1 m/s, v2' = 8.97 m/s

  • Calculating loss of mass: 2 blocks(b') = 20% of original mass of slab = per impact
  • loss = 2b11 + 2 b10 + 2 b9+ 2 b8 + 2b7; 2(20 kg) + 2(20 kg) + 2(40 kg) + 2(80 kg) + 2(160) + 2 (320) = 1240 kg
  • m' = m1 + m2 - loss
  • m' = 4575 kg, v2' = 8.97 m/s

  • Solving for Inelastic: v' = (m1/(m1 + m2))v1
  • m1 = 2615kg, v1 = 9.98 m/s
  • m2 = 3200 kg
  • m'= 5815 kg, v' = 4.48 m/s

  • Conservation of Momentum:
  • initial momentum(p): m1v1 + m2v2 = (m1 + m2)v'; final momentum(p') = m1v1' + m2v2'
  • m1 = 4575 kg, v1 = 8.97 m/s
  • m2 = 5815 kg, v2 = 4.48 m/s
  • v1' = ? m/s, v2' = ? m/s

:
  • v1' = 6.46 m/s, v2' = 6.46 m/s
  • m'= 10,390 kg, v' = 6.46 m/s

Take-away:

  • f8/7/6/5 has a final mass of 10,390 kg and a final velocity of 6.46 m/s,
  • Favg = 1,041,820 N vs f7 = 31,360 N,
  • Floor 5 had the upward force to support 6 floors; Now, it has a downward force equal to 33 sets of 6 floors pushing down on it.

Okay, I think that's enough for tonight.

Now, at this point, the collapse has reached Level 5. The gain in velocity has been getting smaller and smaller, and in the next collapse, we will have reached what is known as the terminal velocity of the collapse. Now, this particular terminal velocity is a bit different from the one in the real world, as it is due to the intentional inclusion of forces that we used to simulate the avalanche gaining mass, loosing mass, colliding elastically, and colliding inelastically, but suffice it to say that there comes a point that all the forces reach a sort of moving version of equilibrium, where even though gravity is still applying a downward pull on a mass, the other forces that are affecting the mass balance out that gain, and the object continues to fall, but does not continue to accelerate.

Also, at this point in the collapse, we have lost all the slab blocks from floors 11, 10, and 9. We are still gaining new mass from each floor we impact, but all of the original slabs that caused the collapse at the beginning are gone with the wind, ejected out the side of our non-existent building.

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The collapse of the WTC is the event, Lilly. He can't refute 9/11 conspiracy theory unless the discussion is about the 9/11 collapse. We note the subject "Reasonable doubt vs. Fallacy of Incredulity".

So your chance of refuting 9/11 conspiracy theory is zero.

You...are not an attentive man.

I'm going to stop talking to you now.

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How about this, how about we let aquatus finish his model and when and if he gets to the point where he says, 'and thus I have refuted demolition conspiracy theories', we can all jump on him with our objections and can go over the science that addresses the differences in his model versus what actually happened at WTC, if he wants to discuss that. This general charge of, 'you're doing it wrong', and worse, 'you're not demonstrating what I think you should be demonstrating', is way premature at this point.

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How about this, how about we let aquatus finish his model and when and if he gets to the point where he says, 'and thus I have refuted demolition conspiracy theories', we can all jump on him with our objections and can go over the science that addresses the differences in his model versus what actually happened at WTC, if he wants to discuss that. This general charge of, 'you're doing it wrong', and worse, 'you're not demonstrating what I think you should be demonstrating', is way premature at this point.

Yet we've already jumped all over him with our objections long before I ever showed up, and not letting him finish his model isn't really an option, is it? He's already game for discussing the 9/11 collapse as he said earlier, so even if he were dictating the discussion here which would be quite impressive, there's no need for us to wait for it.

What do you think will be established when he finishes his model? Is there a doubt or a fallacy I'm not aware of that we're hoping to cure? I think so because it's the subject of the thread and stuff.

Incidentally, real world differences relevant to his model were addressed here:

http://www.unexplained-mysteries.com/forum/index.php?showtopic=248571&st=150#entry4800923

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If I set up an example where a Klingon battlecruiser with a certain mass collides with a Romulan Bird of Prey with a certain mass as my model, then even though the use of these alien spaceships "does not reflect the real world in any way" since they do not exist except in Star Trek, the analysis of the way the collision plays out 'reflects a real world phenomenon'; that was easy, and should have been for you also. Try reading for comprehension instead of narrow literalness and stop being so defensive, he hasn't even fully laid out his model and you're whipping out the insults and demanding he show how your linked 'simulations', et al, are inapplicable already. He might even respond to your points and objections if you would just relax, I would actually be interested in seeing his responses to those too, but you aren't exactly encouraging him to give you the time of day with your ignorant psychological analysis of what he 'knows' and your idiotic diagnosis of doublethink.

That is hilarious. A Klingon battlecruiser and Romulan Bird of Prey do not in any way ‘reflect real world phenomenon’. I guess that’s the type of idiotic assumption necessary to defend ‘doublethink’. Still, thank you for the fitting analogy to describe the fantasy scenario aquatus has presented here. Sorry, I won’t give any leeway whilst he’s trying to pass that off as comparable to the WTC collapse. It is misleading and should be stated so off the bat.

Whether aquatus chooses to respond to the criticisms raised or blithely continue his inaccurate analysis is up to him – I can’t imagine many are even bothered to check the irrelevant workings in his latest posts – and I certainly didn’t demand anything.

For those who are willing to read an entire sentence (as opposed to cutting it in half and pretending the sentence still carries the same meaning):

Some would call the above tactic intellectually dishonest. I am one of those people.

I read the whole post and intellectual dishonesty doesn’t come into it, it doesn’t matter how I present this, your bolded statement is simply contradictory of the other admissions you have made: -

This is not an engineering diagram. This is not even implied to be the only way in which collapses occur. This does not reflect the real world in any way other than as an abstract representation of numbers derived in a manner that cannot exist in the real world. This is nothing more than a mathematical construct reflecting a real world phenomena, but not defining it.

What "real world phenomena" would that be?

But you have a history of making contradicting statements and avoidance of facing up to it so I’m not entirely surprised: -

http://www.unexplain...70#entry4020751

Perhaps if you were so concerned with intellectual honesty you would attach the following note to all of your subsequent calculations so not as to mislead readers who might pick up the latest discussion after reading your opening posts: -

In other words, the numbers are not, and do not, apply to anything other than the example shown here.

And I’m wondering, since it is highly relevant to the calculations that you are presenting and conclusions derived from them, where others may not be able to follow: -

Actually, I had to drop out of engineering. I have a problem with numbers, and it got to be too difficult for me to focus on them accurately enough.

Do you still have a problem with numbers?

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This is important to consider after his detractors have already pointed out that he's assuming floors floating in midair, and they're right. He's overselling us on what he's doing with "actual science" but it cannot translate to the 9/11 collapse because it's inconsiderate of 9/11's variables. I will agree to "I'm running values I made up with simplifications I made up using formulas I looked up in a physics textbook."

Even though you abide by the official theory of the WTC collapses, very well said and I commend your honesty here.

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Okay, and here we are at the end game, the final floors remaining in the collapse of our theoretical tower.

I know it won't matter to those who continually insist otherwise, but for those of you who do actually pay attention to what someone says (as opposed to deciding that you know what they said and don't really need to read to confirm it), allow me to refresh everyone's memories as to both the nature and purpose of this example:

This is an example based on single-point masses reacting in perfect elastic or inelastic collisions.

In other words, the numbers are not, and do not, apply to anything other than the example shown here.

This is not an engineering diagram. This is not even implied to be the only way in which collapses occur. This does not reflect the real world in any way other than as an abstract representation of numbers derived in a manner that cannot exist in the real world. This is nothing more than a mathematical construct reflecting a real world phenomena, but not defining it.

The sole purpose of this example is to give people an idea of the massively unbalanced net forces that are generated in a progressive, linear, collision under the influence of gravity. Nothing more, nothing less. If there is some force you think might have a significant impact, by all means, tell me about it, and I'll see if I can add it to the equation. Otherwise, don't bust my chops because I called one of my abstract masses a concrete slab but didn't properly reference the tensile strength, shear force, or buckle point in the materials data worksheet published by the Association of Anal Retentive Engineers. Again, these are abstract masses, not "real" concrete slabs.

I'll repeat this one, since it seems to be what is giving most of the complainers the most dificulty comprehending:

The sole purpose of this example is to give people an idea of the massively unbalanced net forces that are generated in a progressive, linear, collision under the influence of gravity.

This is in perfect agreement with the original OP:

At the same time, however, there is an acknowledgement that most of us simply aren't all that conversant with some of the sciences involved. Not a problem, as the sciences can be kept as simple as possible, while at the same time acknowledging that, in the real world, things are much more complex. Nor does it have to be strictly the empirical sciences either; probabilities, properly shown and supported, are welcome too.

My very first example came with an explanation and a disclaimer prior to making any claims:

While it is true that velocity adds energy to a moving object, few people really bother to take a good look at just how much energy we are talking about. Of course, in the real world there are many, many more variables involved, but for the purpose of answering the question of how just a few floors collapsing could result in a catastrophic failure of the entire tower, here is a very simplified version of how I understand it. I am by no means a master of physics, and mediocre at best on math, so feel free to correct me if you spot a mistake.

I repeated this in my next post:

Similarly, I am afraid, I am about to throw out some numbers here that some of you will recognize as not actually being 100% correct in application towards engineering, but I am doing so just to try to explain an incredibly compex subject with the most basic formulas that people might recognize.

At that point, some people showed that their misunderstanding of the basics was quite a bit deeper than I had originally estimated. Unable to argue at the level of the basics (coincidentally, the level where it is extremely difficult to hide any BS), the attempt began to try to redefine the simple example into something far more complex: the WTC collapse. I immediately and directly responded:

Not at all. That's too big picture. At this level, all I am trying to do is to give people an idea of just how much energy we are dealing with here. It is my hope that when people notice how ludicrously, ridiculously, large the differences in forces are, they will be able to, all on their own, decide whether or not the conspiracy arguments are valid or merit credibility.

The attempts continued. Every time the attempt was made to redefine the purpose of the example, I responded:

This is more a question of elastic vs inelastic collisions. In the example I have presented, I am using a combination of both depending on which system I am calculating. As I mentioned before, this is a simple example to demonstrate one single aspect of physics, that of the logarythmic increase of energy due to gravity.
The problem is that I am attempting to describe this in the simplest ways that I can, and it is difficult to tell, at times, how much someone knows, how much they don't know, and more importantly, how much people think they know, but don't actually know.
aquatus1, on 29 May 2013 - 10:37 AM, said:

So, what I am attempting to show in this example, is that a slab of concrete that exerts X amount of force while at rest (while simultaneously receiving X amount of force from the slab it is resting on, as per Newton's 3rd), is going to gain dramatic amounts of energy after falling (acceleration due to gravity).

...At this level, all I am trying to do is to give people an idea of just how much energy we are dealing with here.
...It is this unbelievable multiplication of forces involved that I want people to wrap their heads around.
aquatus1, on 29 May 2013 - 10:20 PM, said:

As I mentioned before, this is a simple example to demonstrate one single aspect of physics, that of the logarithmic increase of energy due to gravity.

No, the point is that the amount of energy created by falling objects multiplies at an incredibly dramatic pace. As the forces become more and more ridiculously unbalanced, the behaviour of the objects becomes more and more predictable.

I have a dozen more examples of myself directly addressing what the purpose of these examples are, but I am not going to belabor the point further. I simply note that even now, the same incorrect claim is being made that the purpose of this example is to prove something about the collapse.

I have also been accused of plagarism and of ignorance in regards to the subject presented. All I can say to that is that I have shown every step of my work, and none of my detractors have addressed any of them. Instead, the focus is on dismissing, devaluing, detracting, and denying, but unfortunately, no discussion.

I have also been accused of deception and misrepresentation. Again, I point out that I have been completely transparent in what I am doing. In addition to my first quote up above, I also posted this in the very post where I listed every assumption I was going to make:

As I mentioned previously, in an avalanche scenario, forces are chaotically moving in all directions, in infinite variations, to the point where seemingly paradoxical situations become all but inevitable. In an avalanche situation, you will have objects ricocheting off each other, objects merging together, objects being forced upwards against gravity, and objects pulled downwards faster than freefall. The collapse of a physical structure like a building is an incredibly complex thing that is literally impossible to calculate in any specific way.

So yes, in order to show the accumulation of forces, some limitations need to be set. I have no intention of hiding any assumptions, and again, if you feel something isn't being done correctly or accurately, by all means, lines of discussion are open.

Now, here are some limitations and assumptions this example works under:

When all is said and done, throughout all of this, the numbers remain in display, for everyone to see, with notes as to what I did. None of these numbers have been addressed to date. The whole focus of the detracters has been to try and divert attention from the example, instead of addressing the actual example.

You can almost sense this palpable fear from the other camp. The amount of energy being expended here, the sheer over-the-top reaction to a simple physics demostration, it's baffling that any rational person would be so insecure in their position that even at the most basic of physics, the arguments at the high school level is viewed as a direct and imminent threat to their cherished conspiracy, to the point that there can be not the slightest bit of agreement, not the slightest hint of compromise; "No! Not only will there be absolutely no attempt to address the actual example, there will be no attempt to even accept that the example has any validity in any way, not even as a basic physics, and anyone who even thinks of agreeing that as much as adding two masses together is anything other than absolutely wrong, and anything less than an insult to science and humanity, must be an utter fool!"

Really now, what is it with all the vitriol? What is this fear of learning, this devotion to anti-intellect? Is the support for your beliefs so flimsy that even high school physics must never be discussed in conjunction with them? That even when someone goes out of their way to state over and over again that the examples are not directly applicable to the collapse, talking about it is still responded to as a direct attack on the conspiracy?

Sorry, but I refuse to think that way. Like it or not, physics is physics, and if a better understanding of basic physics results in people listening to some of these arguments and going "You know...that doesn't sound quite right...that doesn't sound like it works the way they are claiming it works..." then I am happy. I am not interested in telling people what to believe. All I want to do is give them the tools to decide for themselves whether there is reasonable doubt in a given claim.

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All right then, let's bring this example to the ground!

When we last left our avalanche, we had a mass of 10,390 kg falling at a rate of 6.46 m/s. Floors 11, 10, and 9 have been, in their entirety, completely destroyed and blown away from our avalanche. We have also noticed a reduction in gained velocity through the board, in impact force, in elastic and inelastic collision, and in final momentum.

In other words, we have reached a point of equilibrium between all the forces pushing downwards and all the forces pushing upwards.

Our avalanche continues:

F8/7/6/5 impacts F4:

  • Solving for velocity(v):
  • v1 = 6.46 m/s, d = 3 m, a = 9.82 m/s2

  • v' = 10.03 m/s, t = .36 s

  • Solving for Impact Force(Favg): distance(d) = 1/2mv2; Favg = 2,090,486 N vs f6 = 125,440 N

  • Solving for Elastic: final velocity(v'1) = ((m1 - m2)/(m1 + m2))v1; v'2 = (2m1/(m1 + m2))v1
  • m1 = 5195 kg, v1 = 10.03 m/s
  • m2 = 6400 kg, v2 = 0 m/s
  • v1' = -1.04 m/s, v2' = 8.99 m/s

  • Calculating loss of mass: 2 blocks(b') = 20% of original mass of slab = per impact
  • loss = 2 b8 + 2b7 + 2b6 + 2b5 ; 2(80 kg) + 2(160) + 2 (320) + 2(640) = 2400 kg
  • m' = m1 + m2 - loss
  • m' = 9195 kg, v2' = 8.99 m/s

Notice how, despite having
less
upwards velocity than floor 10 did when it first impacted on floor 9, we are still ejecting 2 blocks per layer, even though that only amounted to 40 kg for floor 10, but is
over 60 times
that amount at this point in the collapse.
  • Solving for Inelastic: v' = (m1/(m1 + m2))v1
  • m1 = 5195 kg, v1 = 10.03 m/s
  • m2 = 6400 kg
  • m'= 11,595 kg, v' = 4.49 m/s

  • Conservation of Momentum:
  • initial momentum(p): m1v1 + m2v2 = (m1 + m2)v'; final momentum(p') = m1v1' + m2v2'
  • m1 = 9195 kg, v1 = 8.99 m/s
  • m2 = 11,595 kg, v2 = 4.49 m/s
  • v1' = ? m/s, v2' = ? m/s

:
  • v1' = 6.48 m/s, v2' = 6.48 m/s
  • m'= 20,790 kg, v' = 6.48 m/s

Take-away:

  • f7/6/5/4 has a final mass of 20,790 kg and a final velocity of 6.48 m/s,
  • Floor 8 has been completely ejected from the avalanche.
  • Favg = 2,090,486 N vs f4 = 125,440 N,
  • Floor 4 had the upward force to support 7 floors; Now, it has a downward force equal to 17 sets of 7 floors pushing down on it.
  • At this point in our example, we have reached terminal velocity. From here on in, the only increase is going to be in mass.

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Our avalanche continues:

F7/6/5/4 impacts F3:

  • Solving for velocity(v):
  • v1 = 6.48 m/s, d = 3 m, a = 9.82 m/s2

  • v' = 10.05 m/s, t = .36 s

  • Solving for Impact Force(Favg): distance(d) = 1/2mv2; Favg = 4,199,683 N vs f3 = 250,880 N

  • Solving for Elastic: final velocity(v'1) = ((m1 - m2)/(m1 + m2))v1; v'2 = (2m1/(m1 + m2))v1
  • m1 = 10,395 kg, v1 = 10.05 m/s
  • m2 = 12,800 kg, v2 = 0 m/s
  • v1' = -1.04 m/s, v2' = 9 m/s

  • Calculating loss of mass: 2 blocks(b') = 20% of original mass of slab = per impact
  • loss = 2b7 + 2b6 + 2b5 + 2b4; 2(160) + 2 (320) + 2(640) + 2(1280) = 4800 kg
  • m' = m1 + m2 - loss
  • m' = 18,395 kg, v2' = 9 m/s

Notice how, despite having
less
upwards velocity than floor 10 did when it first impacted on floor 9, we are still ejecting 2 blocks per layer, even though that only amounted to 40 kg for floor 10, but is
over 60 times
that amount at this point in the collapse.
  • Solving for Inelastic: v' = (m1/(m1 + m2))v1
  • m1 = 10,395 kg, v1 = 10.05 m/s
  • m2 = 12,800 kg
  • m'= 23,195 kg, v' = 4.45 m/s

  • Conservation of Momentum:
  • initial momentum(p): m1v1 + m2v2 = (m1 + m2)v'; final momentum(p') = m1v1' + m2v2'
  • m1 = 18,395 kg, v1 = 9 m/s
  • m2 = 23,195 kg, v2 = 4.45 m/s
  • v1' = ? m/s, v2' = ? m/s

:
  • v1' = 6.49 m/s, v2' = 6.49 m/s
  • m'= 41,590 kg, v' = 6.49 m/s

Take-away:

  • f6/5/4/3 has a final mass of 41,590 kg and a final velocity of 6.49 m/s,
  • Floor 7 has been completely ejected from the avalanche.
  • Favg = 4,199,683 N vs f3 = 250,880 N,
  • Floor 3 had the upward force to support 8 floors; Now, it has a downward force equal to 17 sets of 8 floors pushing down on it.

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And Finally!

F6/5/4/3 impacts F2:

  • Solving for velocity(v):
  • v1 = 6.49 m/s, d = 3 m, a = 9.82 m/s2

  • v' = 10.05 m/s, t = .36 s

  • Solving for Impact Force(Favg): distance(d) = 1/2mv2; Favg = 8,401,387 N vs f2 = 501,760 N

  • Solving for Elastic: final velocity(v'1) = ((m1 - m2)/(m1 + m2))v1; v'2 = (2m1/(m1 + m2))v1
  • m1 = 20,795 kg, v1 = 10.05 m/s
  • m2 = 25,600 kg, v2 = 0 m/s
  • v1' = -1.04 m/s, v2' = 9 m/s

  • Calculating loss of mass: 2 blocks(b') = 20% of original mass of slab = per impact
  • loss = 2b6 + 2b5 + 2b4 + 2b3; 2(320) + 2(640) + 2(1280) + 2(2560) = 9600 kg
  • m' = m1 + m2 - loss
  • m' = 36,795 kg, v2' = 9 m/s

  • Solving for Inelastic: v' = (m1/(m1 + m2))v1
  • m1 = 5195 kg, v1 = 10.05 m/s
  • m2 = 6400 kg
  • m'= 46,395 kg, v' = 4.5 m/s

  • Conservation of Momentum:
  • initial momentum(p): m1v1 + m2v2 = (m1 + m2)v'; final momentum(p') = m1v1' + m2v2'
  • m1 = 36,795 kg, v1 = 9 m/s
  • m2 = 46,395 kg, v2 = 4.5 m/s
  • v1' = ? m/s, v2' = ? m/s

:
  • v1' = 6.48 m/s, v2' = 6.48 m/s
  • m'= 83,190 kg, v' = 6.49 m/s

Take-away:

  • f5/4/3/2 has a final mass of 83,190 kg and a final velocity of 6.49 m/s,
  • Floor 6 has been completely ejected from the avalanche.
  • Favg = 8,401,387 N vs f2 = 501,760 N,
  • Floor 2 had the upward force to support 9 floors; Now, it has a downward force equal to 17 sets of 9 floors pushing down on it.
  • The next impact is at the 1st floor. At this point, all the mass hits the ground and we assume that the entire avalanche will, at some point in the next .36 s, get to the ground and stay there, even if it makes a few bounces along the way. Therefore, our final impact force is:
  • Favg = 7,007,942 N, which is equivalent to a mass of 715,096 kg. The original mass of our tower was 102,400 kg. For those still using pounds, shillings, and ounces, that's an original mass of 225,611 lbs and a final mass of 6772 tons.

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Even though you abide by the official theory of the WTC collapses, very well said and I commend your honesty here.

Q, I'm the biggest critic of the official response to the 9/11 attacks I know. My criticism just doesn't rely upon implausible conspiracy theories or useless partisan politics that pack it up and go home as soon as the blue team is pulling the lever.

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And that's it! It's finally over, the collapse has ended, the forces have dissipated, and all we are left with is an abstract pile of nonexistent concrete to show for it. I had hoped to present it all in a much shorter time span, but looking back at how I didn't even manage to get to the second stage of my initial example, I suppose that was entirely too optimistic. Since everything is so scattered, I'll just summarize the info here, and if anyone has a question regarding the numbers, we can take it from there.

Please bear in mind the warnings that I made:

  • at the beginning of the thread,
  • the beginning of the example,
  • several times during the middle of the example,
  • pretty much at least once a page,
  • this one here right now,
  • probably the one again at the end of this post,
  • and, I suspect, in my next post, when the usual suspects begin doing their ugly stepsisters routine claiming that I am saying that this is some sort of proof regarding the collapse of the WTC towers.

It isn't, it doesn't, it never has, it was never intended to. This is nothing more than a simple example of progressive collapse under acceleration that will demonstrate the interaction of forces and the differences in growth rates as the collapse progresses. This does not reflect the real world in any way other than as an abstract representation of numbers derived in a manner that cannot exist in the real world. This is nothing more than a mathematical construct reflecting a real world phenomena, but not defining it.

Our tower (at rest):

Floor 11: m= 200 kg = 1960 N

Floor 10: m= 200 kg = 1960 N

Floor 09: m= 400 kg = 3920 N

Floor 08: m= 800 kg = 7840 N

Floor 07: m= 1600 kg = 15,680 N

Floor 06: m= 3200 kg = 31,360 N

Floor 05: m= 6400 kg = 62,720 N

Floor 04: m= 12,800 kg = 125,440 N

Floor 03: m= 25,600 kg = 250,880 N

Floor 02: m= 51,200 kg = 501,760 N
  • Each floor has the amount of force necessary to push up against all the floors above it. Since they are "at rest", with no acceleration relative to each other, this means that to increase the force, we have to increase the mass. The mass of each floor gives it the force necessary to match the force of the masses of all the floor above it.
  • Newtons Law's make no distinction regarding the shape or consistency of a mass (as far as the laws are concerned, all masses are single-point). I have them suspended in the air at 3 meter intervals, but if you feel more comfortable imagining columns holding them apart, by all means, do so. Simply decide how much mass you want each column to represent, and deduct that mass from the slab. This won't affect the calculation in any way.

The Collapse:

  • t = 0.00 s: f11 and f10 begin free-fall,
  • t = 0.78 s: f10 impacts f9
    • f10/9: m' = 560 kg, v' = 3.14 m/s, Favg = 11,552 N, loss = 40 kg,

    [*]t = 1.30 s: f10/9 impact f8

    • f10/9: m' = 1240 kg, v' = 5.14 m/s, Favg = 77,156 N, loss = 120 kg,

    [*]t = 1.35 s: f11 impacts f10/9/8

    • f11/10/9/8: m' = 1400 kg, v' = 4.55 m/s, Favg = 70,543 N, loss = 40 kg,

    [*]t = 1.79 s: f11/10/9/8 impact f7

    • f11/10/9/8/7: m' = 2720 kg, v' = 5.86 m/s, Favg = 223,285 N, loss = 320 kg,

    [*]t = 2.23 s: f11/10/9/8/7 impact f6

    • f11/10/9/8/7/6: m' = 5230 kg, v' = 6.38 m/s, Favg = 507,636 N, loss = 640 kg,

    [*]t = 2.59 s: f11/10/9/8/6 impact f5

    • f9/8/7/6/5: m' = 10, 390 kg, v' = 6.46 m/s, Favg = 1,041,820 N, loss = 1240 kg,

    [*]t = 3.95 s: f8/7/6/5 impact f4

    • f8/7/6/5/4: m' = 20,790 kg, v' = 6.48 m/s, Favg = 2,090,486 N, loss = 2400 kg,

    [*]t = 4.31 s: f7/6/5/4/ impact f3

    • f7/6/5/4/3: m' = 41,590 kg, v' = 6.49 m/s, Favg = 4,199,683 N, loss = 4800 kg,

    [*]t = 4.67 s: f7/6/5/4/3 impact f2

    • f6/5/4/3/2: m' = 83,190 kg, v' = 6.49 m/s, Favg = 8,401,387 N, loss = 9600 kg,

    [*]t = 5.03s: f5/4/3/2 impact Ground

    • Final Impact: m' = 83,190 kg, v' = 6.49 m/s, Favg = 16,804,795 N,

Assumptions:

  • To approximate energy in the form of ricochet or solid block impacts, half the mass was calculated using the Elastic collision equation.
  • To approximate energy in the form of deformation, merging, or breaking, half the mass was calculated using the Inelastic collision equation.
  • To simulate objects in an avalanche being lost out the side, each original slab was divided into 10 blocks, each representing 20% of the original mass. At each impact, all the impacting slabs lost two blocks of mass each. As the avalanche progressed and the individual blocks increased in mass as well as the overall mass of the avalanche increasing, the amount of upward force from the elastic collisions decreased. Despite having less energy to eject mass outwards, we still calculate the same rate of 2 blocks per slab per impact. This is a far, far, greater rate of loss than could be expected in a real-world scenario (In fact, it is impossible. You cannot lose larger and larger amounts of mass using less and less force).
  • Floor 11 was assumed to be in independant free-fall until it caught up with the collapse at the 1.35 s mark.

Points of Interest:

  • When F11 collided with the mass of floors below it, the net result was a decrease in velocity. The avalanche slowed down after being hit from behind.
  • Approximately 3 seconds into the collapse, the avalanche reached terminal velocity.
  • By the time the avalanche struck Floor 5, more downward force had been generated by the avalance than the entire building had available to push upwards.
  • By the time the avalanche hit the ground, the total amount of mass lost out the side was greater than the combined mass of floors 11 through 5.
  • Prior to the collapse, the tower was exerting a downward force of 1,003,520 N on the ground. That is the equivalent of 102,400 kg, or 225,611 lbs.
  • At the time of impact, the avalanche exerted a force of 16,804,795 N on the ground, equivalent to 1,714,774 kg, or 1890 tons.

Okay, good for now. Again, remember, we are talking about abstract masses. These calculations represent a set of forces formerly neatly arrayed and in equilibrium suddenly turned into a linear progressive collapse under constant acceleration. The avalanche represents both elastic and inelastic forces. The upwards force of the elastic collisions were turned into the forcible ejection of mass at a rate far greater than physically possible in the real world.

Next post, we'll talk about some conclusions we can draw from the relationships between the forces that we see hear. I would love to hear your conclusions about the numbers, or what they mean, or even if you spot something that could be improved or that needs to be corrected.

If all you are going to do is tell people to ignore everything, well...we've heard it already. Get a new tune.

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