Science fail x4: supporters of NIST physics still relying on faith, foggy notions, over logic

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Fidel

Pants-of-dog wrote:

Fidel wrote:

Well there's quite a lot there in that pdf describing strength of the steel columns in technical terms, the Johnson Parabola equation used in engineering to determine the critical
buckling stress for inelastic buckling and so on. There's a lot to chew on really.

Then summarise the argument into a few concise sentences, and add quotes from the text that support and clarify your summary.

You seem to expect us to do what NIST and their unscientific lackies Bazant and Greening have failed to do, which is to thoroughly investigate and explain why three building collapsed after two plane collisions and in scientific analysis that satisfies independent scrutiny. I'm sorry, it's not our job to convince 900 engineers and tens of millions of Americans and Canadians that they did the job  right in the first place.  If the buildings fell down due to shoddy workmanship, then hundreds of engineers want to be able to understand it in great detail so as to avoid design flaws in future. The feds spent far more money on a Columbia space shuttle disaster, and a lot more money on investigating a Clinton-Lewinsky sex scandal, and a lot more money to investigate  a Whitewater scandal than was spent on discovering why three white elephants collapsed in the heart of New York City. Hundreds of engineers don't necessarily care whether it was an inside job or not - they need to know because it's among their career obligations to understand what really happened.

Pants-of-dog

jas wrote:
What are Bazant's calculations for the transfer of momentum through the floors, pants?

The same as mine, I would assume. i don't know why you are asking this, as it is irrelevant to the discussion on Ross' mistaken assumptions concerning transfer loads.

jas wrote:
I don't think it's correct or valid to say that "the floors would have failed before transferring the stresses onto the rest of the structure." The stress would have been transferred immediately upon impact.

That's all well and good, but unless you have some sort of logical reason or evidence for your claims, it is merely your opinion.

My logical reason for believing that the structure failed is that some of the columns of upper block must have fallen onto the floor structure (i.e. the composite floor deck, open web steel joists, and the beams supporting the joists), which was not designed to hold the weight of the upper block of storeys. The only parts of the structure on the lower block of storeys that were designed to carry the loads of the upper block were the columns. Since the columns of the upper block did not land exactly on the columns of the lower block, the loads were not capable of being transferred in the way that they were designed to.

jas wrote:
Also, according to Kevin Ryan, as linked to in the last thread,

Quote:
NIST... estimates that loads on some columns increased by up to 35% while loads on other columns decreased by 20%. The increased loads are nowhere near those the designers claimed the columns could handle: increases of 2000% above the design live loads.

So apparently you disagree with NIST again.

I think I disagree with your interpretation of what Kevin Ryan thinks the NIST is saying, which is probably very different from what the NIST is actually saying. In order to resolve this, please provide a link to the NIST report that Ryan is commenting on, a quote of the relevant text from the NIST report, and a link to Ryan's commentary. Thank you.

jas wrote:
Also, you are still talking about the tilting block applying stress to one side of the floor it impacts (in your words, the "hinge" side) creating collapse on that side. Simple physics would tell us that then the block would topple over in the direction it is applying pressure as the "hinge" then breaks and the lower floor breaks below, failing to support it.

I asked in the other thread and I don't believe you've yet answered: why does the tilting block not fall in the direction it is tilting if it is destroying the structure beneath it?

I'm not sure what you think I am claiming. Let us say the plane hit the north side of the tower ( I don't know if it really did, but this is just for the purposes of clarifiyng what I mean), creating a large hole in the exterior north wall.

The upper block would, after a while start to tilt northwards, towards the impacted side. It would rotate around a "hinge" made of the columns along the exterior wall of the south elevation.

It would then keep tilting northwards until the columns on the south side (that make the hinge) fail completely. At this point, it would stop tilting and fall downwards.

Pants-of-dog

jas wrote:
Just wanted to highlight the kind of arguments you put forward in the name of physics. At times you give the impression you understand what you're posting, and then there are the statements like this.

Pants, what "space" are you describing through which this rubble and the upper floor fall? You just said it demolishes the floor below. Therefore it is now meeting the next floor. You seem to be imagining some kind of drop from a height for each floor.

Yes, there is a space between each floor. Buildings are not entirely solid structures but actually contain interior spaces that people occupy. The space in the WTC towers was mostly office space. You may be confused by the terminology. The floor is the actual solid floor that is solid and holds stuff up. The storey is the space that encompasses both the floor and the space above it that is occupied by people, furniture, mechanical ducts, etc.

 

pants wrote:
And, on the other hand, the only analyses you've been posting are from Greening and Bazant, who have already been debunked, as far as I'm concerned.

Why do you think they are debunked? You have been unable so far to provide one valid criticism concerning the physics described in those papers.

 

jas wrote:
The news story was linked to in the "Can a car drive through..." thread. As I've stated before, I'm not going to be chasing after links just because you've come late to the conversation and can't be bothered to catch up or google a simple fact.

The question I asked was: "Can you give us an example where this might have occurred elsewhere, outside of an explosive event?" If you are making a claim that the crushing floors would easily explain the dispersal of hundreds of tiny fragments of human bone onto neighbouring buildings, I would expect you to provide an example of where else this has occurred, or at least some kind of analogy. Otherwise, I can only dismiss your comment as yet more uninformed conjecture.

Pleae provide a link to your previous post. I have reposted many links, as well as posting links to previous posts of mine, whenever you asked me to or when I thought it might help you. I do not see why you can not do the same.

Pants-of-dog

Fidel wrote:

You seem to expect us to do what NIST and their unscientific lackies Bazant and Greening have failed to do, which is to thoroughly investigate and explain why three building collapsed after two plane collisions and in scientific analysis that satisfies independent scrutiny. I'm sorry, it's not our job to convince 900 engineers and tens of millions of Americans and Canadians that they did the job  right in the first place.  If the buildings fell down due to shoddy workmanship, then hundreds of engineers want to be able to understand it in great detail so as to avoid design flaws in future. The feds spent far more money on a Columbia space shuttle disaster, and a lot more money on investigating a Clinton-Lewinsky sex scandal, and a lot more money to investigate  a Whitewater scandal than was spent on discovering why three white elephants collapsed in the heart of New York City. Hundreds of engineers don't necessarily care whether it was an inside job or not - they need to know because it's among their career obligations to understand what really happened.

That is a long rant.

I can not help but notice that you have been unable to summarise the argument.

jas

Pants-of-dog wrote:

jas wrote:
What are Bazant's calculations for the transfer of momentum through the floors, pants?

The same as mine, I would assume. i don't know why you are asking this, as it is irrelevant to the discussion on Ross' mistaken assumptions concerning transfer loads.

How is it irrelevant? If you are claiming Ross makes "mistaken asumptions" on the transfer of stress throughout the building, what are they? Why are Bazant's calculations more accurate, in your opinion? And does Bazant provide for momentum transfer?

pants wrote:
jas wrote:
I don't think it's correct or valid to say that "the floors would have failed before transferring the stresses onto the rest of the structure." The stress would have been transferred immediately upon impact.

That's all well and good, but unless you have some sort of logical reason or evidence for your claims, it is merely your opinion.

My logical reason for believing that the structure failed is that some of the columns of upper block must have fallen onto the floor structure (i.e. the composite floor deck, open web steel joists, and the beams supporting the joists), which was not designed to hold the weight of the upper block of storeys. The only parts of the structure on the lower block of storeys that were designed to carry the loads of the upper block were the columns. Since the columns of the upper block did not land exactly on the columns of the lower block, the loads were not capable of being transferred in the way that they were designed to.

The reason I say that stress would be transferred immediately is because it always is in any kind of sudden impact. This is common sense applied to how materials and structures behave. Your reasoning seems to be merely personal speculation on what might or might not have occurred. eg: "some of the columns of the upper block must have fallen onto the floor structure..."

You also keep repeating that "the columns of the upper block did not land exactly on the columns of the lower block..." There were two Twin Towers. Which building are you referring to here and what is your evidence for this statement?

As for the tilting block, if we look at the photo you posted, which side of the building (i.e., picture) are you saying the jets hit? This will help me to understand what you are saying about it.

Pants-of-dog

jas wrote:
How is it irrelevant?

Because in either case, the exact same momentum would be transferred. Momentum is equal to mass times velocity. I've already given you the mass and the velocity for both upper blocks. You can calculate it if you want, and your calculations will be the same as Bazant's or Ross's or anyone else's.

 

jas wrote:
If you are claiming Ross makes "mistaken asumptions" on the transfer of stress throughout the building, what are they?

He is incorrectly assuming that the structure stays together long enough to transfer the loads in the same way that the structure was designed to do.

 

jas wrote:
Why are Bazant's calculations more accurate, in your opinion?

Bazant's model is more accurate because it is made to reflect the observed data as closely as possible.

 

jas wrote:
And does Bazant provide for momentum transfer?

Yes.

 

pants wrote:
The reason I say that stress would be transferred immediately is because it always is in any kind of sudden impact. This is common sense applied to how materials and structures behave.

If this were true, seat belts and crush zones in cars would not work, as the stress caused by the collision between the vehicle and whatever it hit would immediately be transferred to the passengers, killing them.

Since this is not the case,  we know that this claim of yours is not true.

 

jas wrote:
Your reasoning seems to be merely personal speculation on what might or might not have occurred. eg: "some of the columns of the upper block must have fallen onto the floor structure..."

I thought I was being quite clear on the fact that this definitely occurred. I guess I need to be clearer.

 

jas wrote:
You also keep repeating that "the columns of the upper block did not land exactly on the columns of the lower block..." There were two Twin Towers. Which building are you referring to here and what is your evidence for this statement?

I am referring to both of them. The one with the tilting block obviously did not land exactly on the columns of the lower block, as this would have been impossible as soon as it started tilting. As for the other one, the odds of the columns lining up like that would have been very long indeed.

Imagine taking a stick. Break it in half. Now hold one half so that the brokenend sticks up. Hold the other one over it so that the broken end points down at the other broken end. How many times do you let it go before it lands and stays on the other broken end? Now, imagine this happening for each column. Does that give you an idea of the odds?

 

jas wrote:
As for the tilting block, if we look at the photo you posted, which side of the building (i.e., picture) are you saying the jets hit? This will help me to understand what you are saying about it.

The plane hit the left side of the building (flew in from the left side of the picture, so to speak).

Pants-of-dog

Has anyone ever heard of a magazine called "Popular Mechanist"?

Not Popular Mechanics, but Popular Mechanist.

Or the Hartfordshire Technology Institute?

Or the book "When the Towers Came Down" by Jim Steeves?

Fidel

Pants-of-dog wrote:

That is a long rant.

I can not help but notice that you have been unable to summarise the argument.

Well since you only ever present Bazant or Greening's arguments and sometimes even disagreeing with them without intending to, [url=http://www.vintagemediashop.com/showpost.php?s=d70463fb210329e1a0d66ab44... is Szamboti[/url] explaining how total kinetic energy available for collapse initiation of WTC1 would likely have dissipated through various energy sinks and resulting in collapse arrest after a one story drop. Apparently Greening and Bazant claim to have reviewed Szamboti's paper and found no errors to disagree with his overall thesis on collapse.

Tony Szamboti wrote:
The upper block had 6,725,860 in-k[4.63411754e+13 N/m^2] of kinetic energy at the first collision between floor slabs and the energy of absorption of the columns on just the first story on either side of the collision was 6,060,000 in-k.

Bazant and Greening haven't accounted for the total energy required to collapse steel columns and energy loss due the various energy sinks in play. They want us to believe that all the available energy was directed toward collapsing steel columns on the opposite side of the building where the initial damage was done and no where else. Their's is not a real world analysis. Bazant and Greening are full of baloney.

Fidel

They have some nice ATVs and electronics stuff in Popular Mechanics, a magazine that is peer reviewed by backyard mechanical enthusiasts everywhere, and non-truthers, too, apparently.

Pants-of-dog

Fidel wrote:

Well since you only ever present Bazant or Greening's arguments and sometimes even disagreeing with them without intending to, [url=http://www.vintagemediashop.com/showpost.php?s=d70463fb210329e1a0d66ab44... is Szamboti[/url] explaining how total kinetic energy available for collapse initiation of WTC1 would likely have dissipated through various energy sinks and resulting in collapse arrest after a one story drop. Apparently Greening and Bazant claim to have reviewed Szamboti's paper and found no errors to disagree with his overall thesis on collapse.

Tony Szamboti wrote:
The upper block had 6,725,860 in-k[4.63411754e+13 N/m^2] of kinetic energy at the first collision between floor slabs and the energy of absorption of the columns on just the first story on either side of the collision was 6,060,000 in-k.

You actually quoted someone in another thread on another board?

Even if we assume that the person who is posting as Szamboti is actually the mechanical engineer (not structural or civil engineer) whowrote the PDF you previously linked to, we have no way of checking his calculations for kinetic energy.

In that respect, even I am a better source than Szamboti because I actually showed my kinetic energy calculations.

 

Fidel wrote:
Bazant and Greening haven't accounted for the total energy required to collapse steel columns and energy loss due the various energy sinks in play. They want us to believe that all the available energy was directed toward collapsing steel beams and nothing else. Their's is not a real world analysis. Bazant and Greening are full of baloney.

Please provide evidence for the bolded statement.

Pants-of-dog

Fidel wrote:

They have some nice ATVs and electronics stuff in Popular Mechanics, a magazine that is peer reviewed by backyard mechanical enthusiasts everywhere, and non-truthers, too, apparently.

I haven't been able to find any information on any of these three things ("Popular Mechanist", the Hartfordshire Technology Institute, or the book "When the Towers Came Down" by Jim Steeves) through Google. It's as if they don't exist.

Fidel

Pants-of-dog wrote:

In that respect, even I am a better source than Szamboti because I actually showed my kinetic energy calculations.

Now you're laying claim to Bazant and Greening's calculations? And, what calculations?

Szamboti is a mechanical engineer with more than 20 years of experience.

And you're an anonymous poster named Pants-o-dog and who sometimes without realizing it, disagrees with two NIST lackies he references a lot by the names of Bazant and Greening . Just keepin' it real.Wink

Pants-of-dog

Fidel wrote:
Now you're laying claim to Bazant and Greening's calculations?

Whatever gave you that idea? I have shown Greening's calculations here:

http://rabble.ca/comment/1156932/Here-summary

But I don't lay claim to them. I just redid them to check the math. They were correct.

 

Fidel wrote:
And, what calculations?

Here is where I start doing calculations.

http://rabble.ca/comment/1157296/Fidel-wroteAnd-if-you-have

Did some more here:

http://rabble.ca/comment/1159712/jas-wrote-You-have-never

 

Fidel wrote:
Szamboti is a mechanical engineer with more than 20 years of experience.

Even if that is true, mechanical engineering is not applicable to building collapse. Mechanical engineers design heating systems or machinery, not skyscrapers. Even if they did design skyscrapers,  we would need to see more evidence of his energy comparison (such as his calculations) than we saw in that one post.

 

Fidel wrote:
And you're an anonymous poster named Pants-o-dog

Pants-of-dog. It doesn't have the right air of pretentious annoying arrogance if you drop the f.Wink

 

Fidel wrote:
and who sometimes without realizing it, disagrees with two NIST lackies he references a lot by the names of Bazant and Greening . Just keepin' it real.

Please explain how my argument disagrees with either Bazant's or Greening's. Thank you.

Pants-of-dog

This is the article that jas mentioned in his thread about cars and brick walls. The link to the thread is here:

http://rabble.ca/babble/humanities-science/can-car-drive-through-brick-w...

The article itself is the very first post of the thread, so it is easy to find.

Let us go through it.

First of all, I would like jas to provide a link to the website from which he copied it. The reason why will be apparent shortly.

Now, let us examine the text itself.

Quote:
World News Service -

This news agency apparently does not exist. A [url=http://www.google.ca/webhp?hl=en#hl=en&source=hp&q=%22World+News+Service... search[/url] reveals that the only international organisation calling itself by that name serves the Baha'i community. Please note that the articel does not make any mention of the Baha'i.

Quote:
The NiST official explanation of terrorist bomb plantings in the WTC to explain their within-seconds-of-free-fall collapse after upper floor fires is a bunch of hocus pocus, says a new WTC Truth group.

Read this carefully. The claim is that the NIST are saying it was controlled demolition.

 

Quote:
"The absurd theory that anyone would have had that kind of access to the WTC towers to lay these alleged explosives is just a remnant of Bush-era, anti-science bafflegab...Rather, "those collapses are easily explained by the progressive collapse theory that researchers at WTC Truth have developed."

This WTC Truth group is putting forth a theory of progressive collapse.

Quote:
Jim Steeves, head researcher for WTC Truth

This truth group also does not exist according to Google.

Quote:
and author of When the Towers Came Down

If we went to Google and looked for this book, what do you think would happen?

No, it doesn't exist either.

Quote:
, shows in a new paper, published in the April edition of Popular Mechanist,

No, Popular Mechanist doesn't turn up either.

But let us continue...

Quote:
how, in both cases, the top portions of the buildings began their descent through the impact zone and fire-weakened floors. "... and from there, the rest of the building[s] simply didn't have a chance."...NiST is lying when they say that it was explosives. They're covering up for someone. We don't know who."... 

Steeves and his Truth group have faced much derision for their views, especially with respect to their progressive collapse theory, which, scientists say, is physically impossible....

So, the Truth group is advocating progressive collapse and the NIST are advocating controlled demolition, according to the article.

Quote:
Dr. Tan Philips, professor emeritus at Hartfordshire Technology Institute,

No doctor.

No institute.

Quote:
notes that the WTC collapse time that was within seconds of the rate of gravitational acceleration is not possible "while you have 80 and 90 floors of intact building underneath this supposedly descending mass."

He states, "I see no reason to question the theory of explosives that NiST proposes. It is clear from the video evidence the speed and manner of descent, the pre-explosions that were heard, the blown-out lobbies, the massive cauliflower clouds of pyrotechnic dust, all this leads any rational person to the natural conclusion that explosives were used, much like in controlled demolition." He adds that the progressive collapse theory cannot account for the fall of WTC7.

It goes on.

This is obviously a satire or spoof, and was written to poke fun at people.

I have been unable to find the actual original article. Do you have the link, jas? Or did you write it?

Fidel

Pants-of-dog wrote:
Here is where I start doing calculations.

http://rabble.ca/comment/1157296/Fidel-wroteAnd-if-you-have

Did some more here:

">http://rabble.ca/comment/1159712/jas-wrote-You-have-never

Elastic-inelastic analysis alone is taking momentum transfer out of context according to Gordon Ross.  You have no calculations for energy sinks. There is no energy costing for deformations. And you divide total mass by just 110 floors for an average. What about the five basements? Slip-shod!

Pants-of-dog wrote:
Fidel wrote:
Szamboti is a mechanical engineer with more than 20 years of experience.

Even if that is true, mechanical engineering is not applicable to building collapse. Mechanical engineers design heating systems or machinery, not skyscrapers. Even if they did design skyscrapers, we would need to see more evidence of his energy comparison (such as his calculations) than we saw in that one post.

Here is [url=http://journalof911studies.com/articles/Journal_5_PTransferRoss.pdf]Gordon Ross, mechanical engineer[/url](pdf) with his summary of energy requirements for initial collapse:

Quote:
Energy Summary:
The energy balance can be summarised as
Energy available;
Kinetic energy 2105MJ
Potential energy Additional downward movement 95MJ
Compression of impacting section 32MJ
Compression of impacted section 24MJ
Total Energy available 2256MJ
Energy required;
Momentum losses 1389MJ
Plastic strain energy in lower impacted storey 244MJ
Plastic strain energy in upper impacted storey 215MJ
Elastic strain energy in lower storeys 64MJ
Elastic strain energy in upper storeys 126MJ
Pulverisation of concrete on impacting floor 304MJ
Pulverisation of concrete on impacted floor 304MJ
Total Energy required 2646MJ
Minimum Energy Deficit -390MJ

Conclusion
The energy balance of the collapse moves into deficit during the plastic shortening phase of the first impacted columns showing that there would be insufficient energy available from the released potential energy of the upper section to satisfy all of the energy demands of the collision. [...]

And Ross goes on to say that he hasn't even considered all of the probably energy sinks likely to have extinguished the "pile driver" effect at a number points during collapse.

And furthermore, if Szamboti's experience in structural engineering doesn't apply, then why should we care what Frank Greening, with all his degrees in chemistry, has to say about structural engineering? And if this is going to descend into a my father can beat up your father tiff, then Kevin Ryan has something to say about that.

[url=http://www.globalresearch.ca/index.php?context=va&aid=5071]9/11: Looking for Truth in Credentials: The Peculiar WTC "Experts"[/url]

 

Pants-of-dog

Fidel wrote:
Elastic-inelastic analysis alone is taking momentum transfer out of context according to Gordon Ross.

Then it's a good thing that neither Bazant, Greening nor I limited ourselves only to that.

 

Fidel wrote:
You have no calculations for energy sinks. There is no energy costing for deformations.

Please reread my calculations more carefully. I explicitly mention the energy required to demolish one floor of the WTC towers.

 

Quote:
And you divide total mass by just 110 floors for an average. What about the five basements? Slip-shod!

The five basements have a decidedly different construction, being made almost entirely of reinforced concrete, therefore throwing off the average. Moreover, unless their mass has been added into the total mass,(which I do not believe is the case), it would be even more slip-shod to include them.

 

Fidel wrote:
Here is [url=http://journalof911studies.com/articles/Journal_5_PTransferRoss.pdf]Gordon Ross, mechanical engineer[/url](pdf) with his summary of energy requirements for initial collapse:

Quote:
Energy Summary:
The energy balance can be summarised as
Energy available;
Kinetic energy 2105MJ
Potential energy Additional downward movement 95MJ
Compression of impacting section 32MJ
Compression of impacted section 24MJ
Total Energy available 2256MJ
Energy required;
Momentum losses 1389MJ
Plastic strain energy in lower impacted storey 244MJ
Plastic strain energy in upper impacted storey 215MJ
Elastic strain energy in lower storeys 64MJ
Elastic strain energy in upper storeys 126MJ
Pulverisation of concrete on impacting floor 304MJ
Pulverisation of concrete on impacted floor 304MJ
Total Energy required 2646MJ
Minimum Energy Deficit -390MJ

Conclusion
The energy balance of the collapse moves into deficit during the plastic shortening phase of the first impacted columns showing that there would be insufficient energy available from the released potential energy of the upper section to satisfy all of the energy demands of the collision. [...]

And Ross goes on to say that he hasn't even considered all of the probably energy sinks likely to have extinguished the "pile driver" effect at a number points during collapse.

Ross is incorrectly assuming that the structure stays together long enough to transfer the loads in the same way that the structure was designed to do.

To clarify: Ross is making the incorrect assumption that the stresses imparted to the structure on impact would transfer themselves effectively through the structure without significantly weakening the structure. This is incorrect because the upper block of storeys did not land squarely on the lower structure, but instead landed at an angle due to tilting. This meant that the weight of the upper block landed on parts of the lower structure that were never designed to transmit such a heavy load to the lower floors. These elements would have failed before passing the stresses onto the rest of the structure.

My logical reason for believing that the structure failed is that some of the columns of upper block must have fallen onto the floor structure (i.e. the composite floor deck, open web steel joists, and the beams supporting the joists), which was not designed to hold the weight of the upper block of storeys. The only parts of the structure on the lower block of storeys that were designed to carry the loads of the upper block were the columns. Since the columns of the upper block did not land exactly on the columns of the lower block, the loads were not capable of being transferred in the way that they were designed to.

Consequently, the energy requirements that Ross estimates for demolishing the structure of the lower floors are far higher than what they actually were.

 

Fidel wrote:
And furthermore, if Szamboti's experience in structural engineering doesn't apply, then why should we care what Frank Greening, with all his degrees in chemistry, has to say about structural engineering? And if this is going to descend into a my father can beat up your father tiff, then Kevin Ryan has something to say about that.

[url=http://www.globalresearch.ca/index.php?context=va&aid=5071]9/11: Looking for Truth in Credentials: The Peculiar WTC "Experts"[/url]

I couldn't care less about anyone's credentials. Joe the Plumber could start posting here, and if his math was correct and was consistent with the empirical data, I would concede that he was correct. Szamboti could be a Nobel Prize winning structural engineer for all I care. The trouble is that Szamboti does not show his calculations.

jas

Um, pants, the first post in that thread is fiction. It is intended, and everybody but you seemed to understand it, as a reversal of the current story to demonstrate a point.

jas

But I'm glad you're actually reading the other threads now :)

jas

Pants-of-dog wrote:

Because in either case, the exact same momentum would be transferred. Momentum is equal to mass times velocity. I've already given you the mass and the velocity for both upper blocks. You can calculate it if you want, and your calculations will be the same as Bazant's or Ross's or anyone else's.

But then these calculations are already based on a collapse sequence that can't happen naturally. That's the problem, and that's why you don't like Ross's "assumptions". He's assuming what should happen, based on what structural engineers know about natural failure of large structures. Bazant's calculations merely attempt to ascribe "naturality", scientific legitimacy, to the unnaturality of the collapses.

pants wrote:

He is incorrectly assuming that the structure stays together long enough to transfer the loads in the same way that the structure was designed to do.

See above.

pants wrote:

If this were true, seat belts and crush zones in cars would not work, as the stress caused by the collision between the vehicle and whatever it hit would immediately be transferred to the passengers, killing them.

What you're describing here is the reason why we have seat belts and other safety features - and why people survive collisions much more than they used to.

pants wrote:
I thought I was being quite clear on the fact that this definitely occurred. I guess I need to be clearer.

Maybe you could provide us with the evidence showing that this "definitely" occurred.

pants wrote:
jas wrote:
You also keep repeating that "the columns of the upper block did not land exactly on the columns of the lower block..." There were two Twin Towers. Which building are you referring to here and what is your evidence for this statement?

I am referring to both of them. The one with the tilting block obviously did not land exactly on the columns of the lower block, as this would have been impossible as soon as it started tilting. As for the other one, the odds of the columns lining up like that would have been very long indeed.

Imagine taking a stick. Break it in half. Now hold one half so that the brokenend sticks up. Hold the other one over it so that the broken end points down at the other broken end. How many times do you let it go before it lands and stays on the other broken end? Now, imagine this happening for each column. Does that give you an idea of the odds?

Again you are completely imagining something which may or may not have occurred. This is not evidence, this is personal conjecture.

I don't normally have a problem with personal conjecture as long as it is making a sincere attempt to explain the visual evidence, but you're just making stuff up here. You also are constantly demanding "evidence" from Fidel and I, so I am asking here the same from you.

Pants-of-dog

jas wrote:

Um, pants, the first post in that thread is fiction. It is intended, and everybody but you seemed to understand it, as a reversal of the current story to demonstrate a point.

Then why did you use it as evidence that bone fragments were found on nearby buildings?

jas

Are there any links in that opening post? The link to the news article about the bone fragments is in the post one or two below.

jas

Oh, sorry, pants. The link may not be in that thread, but in another one before it. This is why I'm not prepared to go digging up links for you. Just google it. "Deutschebank" and "bone fragments".

Pants-of-dog

jas wrote:
But then these calculations are already based on a collapse sequence that can't happen naturally. That's the problem, and that's why you don't like Ross's "assumptions". He's assuming what should happen, based on what structural engineers know about natural failure of large structures. Bazant's calculations merely attempt to ascribe "naturality", scientific legitimacy, to the unnaturality of the collapses.

No. Ross is not making an assumption that any intelligent person would make: he is assuming that the structure above the impact zone and below the impact zone magically lined perfectly during collapse so that the columns from the upper block landed perfectly on the columns from the lower block.

Please note that in your criticism of Bazant, you simply mention some vague notions about unnaturality, while my criticisms of Ross are specific and verifiable.

jas wrote:
What you're describing here is the reason why we have seat belts and other safety features - and why people survive collisions much more than they used to.

Really? I thought I was disproving your claim that impact stresses transfer immediately during an impact.

jas wrote:
Maybe you could provide us with the evidence showing that this "definitely" occurred.

I did. I pointed out that since the upper block of storeys was tilitng, it would be impossible for all the columns to line up perfectly. Since the columns did not line up perfectly, some of the columns from the upper block must have impacted on the floor area of the floor below. By floor area, I mean the horizontal surface that people walked on. This part of the floor was composed of a thin deck supported by joists, and was not designed to hold up the weight of all the floors above.

If the columns hadn't landed at all on the floor area, it would have either landed perfectly on the lower columns and not collapsed, as Ross argues, or far more likely, it would have fallen completely outside the footprint of the building. But then there would have had to have been some sort of large lateral (that means sideways) force acting on the upper block.

The odds of landing perfectly on the lower columns were astronomically long for th etower that didn't have a tilting upper block. For the tower with the tilting upper block, such an alignment of columns would have simply been impossible.

jas wrote:
Again you are completely imagining something which may or may not have occurred. This is not evidence, this is personal conjecture.

I don't normally have a problem with personal conjecture as long as it is making a sincere attempt to explain the visual evidence, but you're just making stuff up here. You also are constantly demanding "evidence" from Fidel and I, so I am asking here the same from you.

It is not an unreasonable assumption that a tilting block will not be able to straighten itself out to be perfectly level and plumb while collapsing through a distance of less  than ten metres and is not being acted on by any force except gravity. Itwoul dbe lik etaking a salt shaker, whacking the bottom of it so that salt flies up through the little holes, and then catching all the salt in the little holes of the salt shaker.

It's possible, but no one can seriously be expected to assume this happened.

jas

Sometimes, depending on the connection I'm on, I can't actually do the quick side research in another tab or window that one normally can do on a good connection.

jas

Pants-of-dog wrote:

Really? I thought I was disproving your claim that impact stresses transfer immediately during an impact.

No, I think you're directly contradicting the very point you're trying to make.

pants wrote:
I did. I pointed out that since the upper block of storeys was tilitng,

again, you are referring to one building only, and in this case, as I've stated before, using the same kind of personal conjecture you use, the collapse would be partial only.

Are you aware that only 14% and 15% of the columns are estimated by NIST to have been severed by the jet impacts?

pants wrote:
it would be impossible for all the columns to line up perfectly.

Sorry, pants, but when you use words like would, you are not citing evidence.

Pants-of-dog

jas wrote:

Oh, sorry, pants. The link may not be in that thread, but in another one before it. This is why I'm not prepared to go digging up links for you. Just google it. "Deutschebank" and "bone fragments".

The spoof story clearly mentions bone fragments:

Quote:
Other facts that confirm explosives and not fire brought the buildings down: WTC5 burned for 6 hours on that day, longer than any of the others, but did not collapse. In 1975, the North Tower's 11th floor burned for 3 hours and the building did not collapse. In April 2006, human bone fragments were found on top of neighbouring buildings,

You also make no comment at all that this is a spoof article in your OP or anywhere else in that thread. Perhaps I missed it, but it seems like there was absolutely no discussion at all about the satirical nature of this article.

When I use Babble's search function to look for discussion on bone fragments, the only article quoted in any of the results is the spoof article.

http://www.rabble.ca/search/apachesolr_search/bone+fragments

 

Pants-of-dog

jas wrote:
No, I think you're directly contradicting the very point you're trying to make.

Please explain how.

jas wrote:
again, you are referring to one building only, and in this case, as I've stated before, using the same kind of personal conjecture you use, the collapse would be partial only.

No, I pretty clearly discuss both scenarios, the tilting block and the one that is not tilting. I said it was flat out impossible for the tilting block, and highly improbable for the one that didn't tilt.

jas wrote:
Are you aware that only 14% and 15% of the columns are estimated by NIST to have been severed by the jet impacts?

And if it had stopped there, the builidng would probably have stood up, but the rest of the columns went on to fail as well due to fire and overloading.

jas wrote:
Sorry, pants, but when you use words like would, you are not citing evidence.

Actually, I think a clear and well thought logical explanation (including two different examples of simple experiments you can do with salt or broken sticks!) as to why it is physically improbable that the columns would not line themselves up perfectly does count as evidence.

Now, please present me any evidence at all (including a simple explanantion as to why you think they would) that the columns lined up themselves perfectly after collapse initiation.

jas

Sorry you're having difficulty.

jas wrote:

Just google it. "Deutschebank" and "bone fragments".

Pants-of-dog

jas wrote:

Sorry you're having difficulty.

jas wrote:

Just google it. "Deutschebank" and "bone fragments".

No, thanks. I wouldn't want you to think that I was cherry picking my sources in order to make you lok bad. I'll do the honourable thing and let you choose your own source to back up your claim.

jas

Pants-of-dog wrote:

Now, please present me any evidence at all (including a simple explanantion as to why you think they would) that the columns lined up themselves perfectly after collapse initiation.

In order for the building to stand and function as a building pre-impact, the columns would have had to be lined up. Perfectly. Right?

When the jets severed 14 to 15% of the columns in the impact zone, if any collapse were possible, (i.e., assuming no explosive events) asymmetrical failure and collapse would have resulted, if any. Right?

We see this in one building only. In that building, once collapse begins, the asymmetry halts itself, and the building descends more or less symmetrically. In the other building descent occurs rapidly and more or less symmetrically. Both from local, asymmetrical (and small, relative to the rest of the building) damage. This is not logical.

 

Pants-of-dog

jas wrote:
In order for the building to stand and function as a building pre-impact, the columns would have had to be lined up. Perfectly. Right?

This is correct.

 

jas wrote:
When the jets severed 14 to 15% of the columns in the impact zone, if any collapse were possible, (i.e., assuming no explosive events) asymmetrical failure and collapse would have resulted, if any. Right?

While an asymmetrical collapse is more likely, a more or less symmetrical collapse is not impossible.

 

jas wrote:
We see this in one building only. In that building, once collapse begins, the asymmetry halts itself, and the building descends more or less symmetrically.

The upper block stops rotating, this is true. The descent of the upper block after it falls is straight down. That is also correct, but the upper block did not starighten itself out after it stopped rotating. It was still at an angle compared to the lower block.

 

jas wrote:
In the other building descent occurs rapidly and more or less symmetrically. Both from local, asymmetrical (and small, relative to the rest of the building) damage. This is not logical.

In my salt shaker experiment, there are only minor lateral forces. Do you think the salt lands back in the little holes of the salt shaker? Obviously not, because you understand that even small lateral forces can make a big difference when lining up so many relatively small things (i.e cross sections of columns).

Moreover, you are forgetting the fact that some of the columns were still there, some only partially, while some had been completely removed. This means that the columns on the bottom of the upper block and the columns on the top of the lower block would probably not line up in terms of the height of each column.

To clarify what I mean by that, open and close your mouth. Your teeth close against each other in such a way that everything lines up. Now imagine if three of your teeth randomly grew longer so that all three were different heights and longer than the rest of your teeth. Your mouth would no longer close properly even though your teeth all line up on top of each other because the height sof the teeth don't match up.

I hope that clarifies things.

Fidel

Pants-of-dog wrote:

Fidel wrote:
Elastic-inelastic analysis alone is taking momentum transfer out of context according to Gordon Ross.

Then it's a good thing that neither Bazant, Greening nor I limited ourselves only to that.

That's right, you only limit yourself to the pseudo-scientific claims of two nutters for the crazy George II side of the argument against that of more than 900 engineers for truth. And it's not helping you any.

Pants-of-dog wrote:
Fidel wrote:
You have no calculations for energy sinks. There is no energy costing for deformations.

Please reread my calculations more carefully. I explicitly mention the energy required to demolish one floor of the WTC towers.

Oh you quote someone else's off the cuff numbers, a chemist's I think. He's wrong according to independent engineers. That's the trouble with putting all your eggs in one or two baskets- you never know if it's safe from scrutiny.

Pants-of-dog wrote:
Quote:
And you divide total mass by just 110 floors for an average. What about the five basements? Slip-shod!

The five basements have a decidedly different construction, being made almost entirely of reinforced concrete, therefore throwing off the average. Moreover, unless their mass has been added into the total mass,(which I do not believe is the case), it would be even more slip-shod to include them.

Well of course it's going to be massive, but it's still part of the same building. The towers weren't a homogenous mass from the much stronger base to the lightest and weaker uppermost portions of the building alleged to have crushed the lower into smithereens by a limitless supply of energy directed only to structural areas selected by unscientific non-truthees. Were there no steel columns in the basements?

Pants-of-dog wrote:
Fidel wrote:
Here is [url=http://journalof911studies.com/articles/Journal_5_PTransferRoss.pdf]Gordon Ross, mechanical engineer[/url](pdf) with his summary of energy requirements for initial collapse:

Quote:
Energy Summary:
The energy balance can be summarised as
Energy available;
Kinetic energy 2105MJ
Potential energy Additional downward movement 95MJ
Compression of impacting section 32MJ
Compression of impacted section 24MJ
Total Energy available 2256MJ
Energy required;
Momentum losses 1389MJ
Plastic strain energy in lower impacted storey 244MJ
Plastic strain energy in upper impacted storey 215MJ
Elastic strain energy in lower storeys 64MJ
Elastic strain energy in upper storeys 126MJ
Pulverisation of concrete on impacting floor 304MJ
Pulverisation of concrete on impacted floor 304MJ
Total Energy required 2646MJ
Minimum Energy Deficit -390MJ

Conclusion
The energy balance of the collapse moves into deficit during the plastic shortening phase of the first impacted columns showing that there would be insufficient energy available from the released potential energy of the upper section to satisfy all of the energy demands of the collision. [...]

And Ross goes on to say that he hasn't even considered all of the probably energy sinks likely to have extinguished the "pile driver" effect at a number points during collapse.

Ross is incorrectly assuming that the structure stays together long enough to transfer the loads in the same way that the structure was designed to do.

To clarify: Ross is making the incorrect assumption that the stresses imparted to the structure on impact would transfer themselves effectively through the structure without significantly weakening the structure.

No what he's saying is perfectly in-tune with Newtonian laws of nature which that demand a significant reduction of velocity after a significant expenditure of energy. The energy has to go somewhere, and it can't all be directed toward snapping steel columns and steel columns only. The tooth fairy might be that tidy but not the forces of nature. Physics and energy balances don't work like this. And Ross isn't even accounting for all possible energy sinks just the most significant ones.

And this is where the handful of guvmint guys and their unscientific groupees have no alternative but to resort to making wild assumptions about momentum transfers directed in only a certain way without any considerations for the many energy sinks and deformations. It's as ridiculous as the wild assumption that 250 massive steel beams all failed in far less time than a blink of an eye according to Manuel Garcia(one in a trillion odds). This is where the handful of guvmint guys and their unscientific groupees sound like conspiracy theorists themselves. They might as well propose that the tooth fairy's evil twin was working overtime on 9/11, it's that stupid.

Pants-of-dog wrote:
Consequently, the energy requirements that Ross estimates for demolishing the structure of the lower floors are far higher than what they actually were.

Sure, if you discount Newtonian laws of nature, I suppose anything can happen then. Maybe in a parallel universe,that one where the tooth fairy's evil alter ego is the patron demon of tall buildings?

Pants-of-dog wrote:
The trouble is that Szamboti does not show his calculations.

NIST is hiding behind the pseudo-scientific calculations of a couple of lackies to an official conspiracy theory with Bazant and Greening posing as their stooges. And those guys reek of stale baloney. And besides, Greening and Bazant have already validated Szamboti's paper by saying they found no errors with it or anything that undermines his basic thesis. So I have no idea you're talking about in that regard.

Pants-of-dog

Fidel wrote:
That's right, you only limit yourself to the pseudo-scientific claims of two nutters for the crazy George II side of the argument against that of more than 900 engineers for truth. And it's not helping you any.

You make a lot of wind about how unscientifc Greening, Bazant, the NIST and I are.

You never back it up with any evidence.

 

Fidel wrote:
Oh you quote someone else's off the cuff numbers, a chemist's I think. He's wrong according to independent engineers. That's the trouble with putting all your eggs in one or two baskets- you never know if it's safe from scrutiny.

Oh look! Another accusation of lack of scientific accuracy! And still no evidence!

Fidel wrote:
Well of course it's going to be massive, but it's still part of the same building. The towers weren't a homogenous mass from the much stronger base to the lightest and weaker uppermost portions of the building alleged to have crushed the lower into smithereens by a limitless supply of energy directed only to structural areas selected by unscientific non-truthees. Were there no steel columns in the basements?

No, there were probably no steel columns in the basement. Most buildings have reinforced concrete substructures. Those that do not will still have their entire substructure made of one material, and not several. This is because materials react differently to humidity and temperature. If the outside foundation wall was concrete and the interior columns were steel, the interior would move differently than the outside wall, causing large cracks to appear in the building and possibly causing structural damage.

Reinforced concrete is water-resistant while steel is not. This is why concrete is almost always chosen for foundations.

As for the claim that the superstructure of the buildings was not homogenous, the only difference in the structure from floor to floor would have been the thickness and overall dimensions of the structural columns. The differences in weight between storeys due to this would have been negligible.

 

Fidel wrote:
No what he's saying is perfectly in-tune with Newtonian laws of nature which that demand a significant reduction of velocity after a significant expenditure of energy. The energy has to go somewhere, and it can't all be directed toward snapping steel columns and steel columns only. Physics and energy balances don't work like this. And Ross isn't even accounting for all possible energy sinks just the most significant ones.

And this is where the handful of guvmint guys and their unscientific groupees have no alternative but to resort to making wild assumptions about momentum transfers directed in only a certain way without any considerations for the many energy sinks and deformations. It's as ridiculous as the wild assumption that 250 massive steel beams all failed in far less time than a blink of an eye according to Manuel Garcia(one in a trillion odds). This is where the handful of guvmint guys and their unscientific groupees sound like conspiracy theorists themselves. They might as well propose that the tooth fairy's evil twin was working overtime on 9/11, it's that stupid.

...

Sure, if you discount Newtonian laws of nature, I suppose anything can happen then. Maybe in a parallel universe,that one where the tooth fairy's evil alter ego is the patron demon of tall buildings?

...

NIST is hiding behind the pseudo-scientific calculations of a couple of lackies to an official conspiracy theory with Bazant and Greening posing as their stooges. And those guys reek of stale baloney. And besides, Greening and Bazant have already validated Szamboti's paper by saying they found no errors with it or anything that undermines his basic thesis. So I have no idea you're talking about in that regard.

More accusations of scientific incompetency without any evidence to support such criticisms.

Fidel

Pants-of-dog wrote:
No, there were probably no steel columns in the basement. Most buildings have reinforced concrete substructures. Those that do not will still have their entire substructure made of one material, and not several. This is because...

Bullshit!

wikipedia wrote:
The core of the towers housed the elevator and utility shafts, restrooms, three stairwells, and other support spaces. The core -a combined steel and concrete structure-[28][29] of each tower was a rectangular area 87 by 135 feet (27 by 41 m) and contained 47 steel columns running from the bedrock to the top of the tower.

jas

Fidel, I think pants is going to have problems with the "assumptions" in any analysis we provide because they are assumptions about how buildings should and do normally collapse, and what kind of energy is expended in crushing storey after storey of concrete and structural steel. Bazant's calculations have to explain an unnatural failure which takes as an a priori fact that "the buildings didn't hold together long enough for stresses to be transferred", ignoring any question as to why that is the case beyond a collapse scenario that they have been assigned to validate. It's a conveniently circular argument.

Pants-of-dog

Fidel wrote:
Bullshit!

wikipedia wrote:
The core of the towers housed the elevator and utility shafts, restrooms, three stairwells, and other support spaces. The core -a combined steel and concrete structure-[28][29] of each tower was a rectangular area 87 by 135 feet (27 by 41 m) and contained 47 steel columns running from the bedrock to the top of the tower.

Wow. You actually provided evidence. Guess I was wrong.

Since that doesn't change the mass of the buildings, or the average mass of each floor, in an appreciable way, I am not sure where you are going with this argument, but please continue.

 

jas wrote:
Fidel, I think pants is going to have problems with the "assumptions" in any analysis we provide because they are assumptions about how buildings should and do normally collapse, and what kind of energy is expended in crushing storey after storey of concrete and structural steel. Bazant's calculations have to explain an unnatural failure which takes as an a priori fact that "the buildings didn't hold together long enough for stresses to be transferred", ignoring any question as to why that is the case beyond a collapse scenario that they have been assigned to validate. It's a conveniently circular argument.

Let's be clear about what assumptions we are discussing.

Ross is assuming that the towers fell in such a way that the columns lined themselves up perfectly in just the right way so that the loads were transferred as they would be if the building were completely intact.

I am assuming that they did not fall in that exact perfect way.

Please explain how my assumption is less logical than Ross"s asumption.

jas

Pants-of-dog wrote:

Let's be clear about what assumptions we are discussing.

Ross is assuming that the towers fell in such a way that the columns lined themselves up perfectly in just the right way so that the loads were transferred as they would be if the building were completely intact.

I am assuming that they did not fall in that exact perfect way.

Please explain how my assumption is less logical than Ross"s asumption.

Well, for one, Ross is responding to what NIST claims about how the buildings descended, not what you claim.

Two, you are only talking about WTC2.

Three, you yourself claim, regarding WTC2, that the remaining columns in the damaged zone that the upper block hasn't crushed through yet (the "hinge", as you call it) then give way, allowing the upper block to right itself, i.e., become level. Since the rest of the collapse ensues symmetrically on the remaining structure which is still intact, the remaining intact columns are indeed lined up because the collapse proceeds sequentially and they are holding the building up for the piledriver to do its magic action.

As for WTC1, I personally wouldn't doubt that the upper block should descend asymmetrically, as the damage was asymmetrical. Any collapse also would be arrested at this stage because it is asymmetrical and, therefore, not able to crush the floor as a whole. However, video footage shows it (while it is visible) descending pretty much symmetrically. There is no evidence of the upper block of WTC1 tilting significantly.

Either way, whether the buildings descended symmetrically or asymmetrically doesn't really matter. They could not descend at that speed without resistance having been removed.

Pants-of-dog

jas wrote:
Well, for one, Ross is responding to what NIST claims about how the buildings descended, not what you claim.

To be honest, your understanding of the underlying physics is such that I do not trust you to fully understand what the NIST is saying, what Bazant is saying, or even what Ross is saying. Again, if you are going to claim this, I suggest you that actually explain how Ross is responding to NIST and how this relates to the discussion.

In my opinion, it is irrelevant to whom Ross is responding, as the model he has fashioned in his response is faulty. This would be true even if he were responding to my mother or Bazant or whomever else.

 

jas wrote:
Two, you are only talking about WTC2.

If you honestly believe this, then you have not been paying attention. I have clearly discussed both scenarios several times. Would you like me to go over them again?

 

jas wrote:
Three, you yourself claim, regarding WTC2, that the remaining columns in the damaged zone that the upper block hasn't crushed through yet (the "hinge", as you call it) then give way, allowing the upper block to right itself, i.e., become level.

No. In fact, I said the exact opposite. I said that once the hinges gave way, the upper block would stop rotating, but it would stay tilted. It just wouldn't tilt any further. (see my third paragraph in post 81)

Please read my posts more carefully.

 

jas wrote:
Since the rest of the collapse ensues symmetrically on the remaining structure which is still intact, the remaining intact columns are indeed lined up because the collapse proceeds sequentially and they are holding the building up for the piledriver to do its magic action.

Obviously this does not follow as the columns could not have been lined up perfectly.

 

jas wrote:
As for WTC1, I personally wouldn't doubt that the upper block should descend asymmetrically, as the damage was asymmetrical. Any collapse also would be arrested at this stage because it is asymmetrical and, therefore, not able to crush the floor as a whole. However, video footage shows it (while it is visible) descending pretty much symmetrically. There is no evidence of the upper block of WTC1 tilting significantly.

I would like some sort of evidence that the bolded statements are true.

 

jas wrote:
Either way, whether the buildings descended symmetrically or asymmetrically doesn't really matter. They could not descend at that speed without resistance having been removed.

No, this is simply wrong. You have not presented any evidence to support this statement that has not been shown to be incorrect. You have put up Chandler's work and I have shown how it is a misapplication of Newton's Third law. You have shown Ross's work and I have shown how it is built on a faulty assumption.

Fidel

This is absolutely hilarious from an exchange between Frank Greening and Steven Jones last year on [url=http://911blogger.com/node/20094]911 Blogger[/url]:

Quote:
On April 19, 2009 F. Greening wrote to me and I replied:

FG: "I would say that Chandler's slight of hand is the implied notion that Newton's 3rd Law is universally applicable, even to a collapsing building. The fact is that when a building is collapsing by multiple floor failures the reaction force obviously fails to balance the downward force because the yield strength of the failing columns is being exceeded."

SJ: No. This is a blatant and fundamental error. I have caught many a student on the equivalent of this nonsense, as I taught Newtonian Mechanics for over 21 years. Newton's 3rd law is always applicable, even in the case you mention, Frank. The key is that the "equal and opposite forces" must act on DIFFERENT bodies. Suggest you consult a basic physics or mechanics text if you don't understand that. - Steven Jones

Later the same day, FG persists in his misunderstanding of Newton's Laws and says:...

Sir Isaac Newton & Steven Jones versus Frank Greening Tongue out

Pants-of-dog

Fidel wrote:

This is absolutely hilarious from an exchange between Frank Greening and Steven Jones last year on [url=http://911blogger.com/node/20094]911 Blogger[/url]:

....

Sir Isaac Newton & Steven Jones versus Frank Greening Tongue out

Greening is correct on that Newton's 3rd law is not universally applicable in the way that Chandler is doing so.

I had previously shown how Chandler is incorrect by showing how Newton's Third Law is actually derived from the law of conservation of momentum, and then all that math I did and showed was all a mathematical analysis of the model using conservation of momentum.

One of the main reasons for doing this is that Chandler's force analysis is only good for rigid bodies. Bazant and Greening's energy analyses are good for rigid and deforming bodies. Since the lower is deforming in that it is collapsing, and the upper block is deforming in that it is accumulating a layer of compacted rubble under it, it makes more sense to use energy models rather than force diagrams.

If anyone would like to see the entire conversation between Greening and Chandler, and not just an edited version from a biased website, please go here:

http://the911forum.freeforums.org/newton-s-3rd-law-and-the-collapse-of-w...

The person posting with the name OneWhiteEye seems to have a good understanding of all the arguments and does not seem to care which side is correct. I suggest that people follow his or her commentary for a good understanding of the issues. However, his or her analyses are a bit difiicult to follow for those who have no background in physics or calculus.

jas

Pants-of-dog wrote:

In my opinion, it is irrelevant to whom Ross is responding, as the model he has fashioned in his response is faulty. This would be true even if he were responding to my mother or Bazant or whomever else.

Actually, yes, his model is based on what Bazant and Zhou claim. If you're having difficulties with that, then I would suggest your difficulties are with them, not him.

pants wrote:

No. In fact, I said the exact opposite. I said that once the hinges gave way, the upper block would stop rotating, but it would stay tilted. It just wouldn't tilt any further. (see my third paragraph in post 81)

That's even nuttier. And here I was trying to come to some common point of agreement with you. I also note that it is entirely Pants-of-dog conjecture. Not sure it's all that relevant.

pants wrote:
Obviously this does not follow as the columns could not have been lined up perfectly.

Your columns-not-lined-up theory is silly and irrelevant. The columns don't need to be lined up perfectly in either scenario: either for the so-called progressive collapse, or for a complete arrest of collapse.

pants wrote:

I would like some sort of evidence that the bolded statements are true.

I only said that because you seem to be suggesting that both buildings had tilting upper blocks and that the columns wouldn't therefore be lined up etc... Again, I don't really care. But just for the sake of pointing out some elemental physics to you, if a structure suffers localized, asymmetrical damage (if you can call it that) then any collapse would be local and asymmetrical.

You keep wanting to turn this into rocket science, and it simply isn't.

pants wrote:

No, this is simply wrong. You have not presented any evidence to support this statement that has not been shown to be incorrect. You have put up Chandler's work and I have shown how it is a misapplication of Newton's Third law. You have shown Ross's work and I have shown how it is built on a faulty assumption.

You have only shown that you don't like the assumptions; you haven't been able to show that they are incorrect. And you're trying to pass off your personal theory as the official theory, which confuses the "debate".

jas

As for the math you started showing us, pants, is there more to those calculations? Unless I missed something, you seem to only calculate the collapse of the first floor below the impact zone. Already we know those are incorrect because you're adding some imaginary "mass" to the piledrivin' upper block, which, in your theory, is only rubble, and in reality is actually probably more like powder.

What happens after that first collapse? And where is the loss of mass due to pulverization accounted for there and in each subsequent collapse? Thank you.

Pants-of-dog

jas wrote:
Actually, yes, his model is based on what Bazant and Zhou claim. If you're having difficulties with that, then I would suggest your difficulties are with them, not him.

No. In Bazant's model, the upper block is only resisted by the structure of one floor at a time. In Ross's model, the upper blockis resisted by the structure of several floors at once. His model is a response to what Bazant and Zhou claim.

 

jas wrote:
That's even nuttier. And here I was trying to come to some common point of agreement with you. I also note that it is entirely Pants-of-dog conjecture. Not sure it's all that relevant.

What, exactly, is so nutty about it?. Please be specific.

 

jas wrote:
Your columns-not-lined-up theory is silly and irrelevant. The columns don't need to be lined up perfectly in either scenario: either for the so-called progressive collapse, or for a complete arrest of collapse.

Why is it irrelevant? Please be specific.

Obviously, the columns do not need to be lined up perfectly for collapse to occur. But they do need to line up perfectly if you want a skyscraper to stop collapsing after such damage.

 

jas wrote:
I only said that because you seem to be suggesting that both buildings had tilting upper blocks and that the columns wouldn't therefore be lined up etc... Again, I don't really care. But just for the sake of pointing out some elemental physics to you, if a structure suffers localized, asymmetrical damage (if you can call it that) then any collapse would be local and asymmetrical.

You keep wanting to turn this into rocket science, and it simply isn't.

If I build a tripod, put it up, and then cut off one leg with an axe, it does not stay standing.

There. I have just disproved your claim about local asymmetrical damage only causing local asymmetrical collapse.

I did it using a model of the simplest structure I could imagine. You're right, it's not rocket science. And I don't need rocket science to show how you are wrong.

 

jas wrote:
You have only shown that you don't like the assumptions; you haven't been able to show that they are incorrect. And you're trying to pass off your personal theory as the official theory, which confuses the "debate".

No. That math I did showed that there was conservation of momentum during the collapse. Since Newton's 3rd law is actually based on the law of conservation of momentum, we can safely say that anything that does not violate the law of conservation of momentum also does not violate Newton's 3rd law. Since my math showed that the collapse does not violate the law of conservation of momentum, we can see that Chandler's claim that it violates Newton's 3rd law is simply wrong.

 

jas wrote:
As for the math you started showing us, pants, is there more to those calculations? Unless I missed something, you seem to only calculate the collapse of the first floor below the impact zone. Already we know those are incorrect because you're adding some imaginary "mass" to the piledrivin' upper block, which, in your theory, is only rubble, and in reality is actually probably more like powder.

What happens after that first collapse? And where is the loss of mass due to pulverization accounted for there and in each subsequent collapse? Thank you.

If you go back and reread what I said at the end of the...

I'll just quote it for you.

http://rabble.ca/comment/1159712/jas-wrote-You-have-never

Pants-of-dog wrote:

Please note that the kinetic energy for the upper block and the velocity for the upper block were faster at the moment of impacting the second lower floor than they were when the upper block impacted the first lower floor.

This shows clearly that the upper block crashed through the lower floors at ever increasing speeds.

What this means is that I took the smaller of the two upper blocks, calculated its kinetic energy and velocity right before it hit the first floor down, and then again right before it hit the next floor down.

If the kinetic energy and velocity were lower when it hit the second floor on the way down, it would have eventually slowed and stopped once it bashed through a certain number of storeys.

But since the kinetic energy and velocity were higher when it hit the second floor on the way down, that means that the upper block got faster and had more energy as it fell through each floor. So, it would have just gone through each lower floor with more KE and more velocity after each floor.

Fidel

Pants-of-dog wrote:

Fidel wrote:

This is absolutely hilarious from an exchange between Frank Greening and Steven Jones last year on [url=http://911blogger.com/node/20094]911 Blogger[/url]:

....

Sir Isaac Newton & Steven Jones versus Frank Greening Tongue out

Greening is correct on that Newton's 3rd law is not universally applicable in the way that Chandler is doing so.

I had previously shown how Chandler is incorrect by showing how Newton's Third Law is actually derived from the law of conservation of momentum, and then all that math I did and showed was all a mathematical analysis of the model using conservation of momentum.

One of the main reasons for doing this is that Chandler's force analysis is only good for rigid bodies.

Well I can certainly appreciate what the poster Heiwa says about Bjorkman's axiom:

Quote:
[url=http://heiwaco.tripod.com/nist.htm]Björkman's axiom[/url] regarding any structure says:

A smaller part of an isotropic or composite 3-D structure, when dropped on and impacting a greater part of same structure by gravity, cannot one-way crush down the greater part of the structure.

Quote:
"[url=http://en.wikipedia.org/wiki/Newton%27s_laws_of_motion#Newton.27s_third_... III:[/url] Actioni contrariam semper et æqualem esse reactionem: sive corporum duorum actiones in se mutuo semper esse æquales et in partes contrarias dirigi. "

" To every action there is always an equal and opposite reaction: or the forces of two bodies on each other are always equal and are directed in opposite directions. - Sir Isaac Newton, [url=http://en.wikipedia.org/wiki/Philosophi%C3%A6_Naturalis_Principia_Mathem... Naturalis Principia Mathematica[/url]

Newton and Kepler to the rescue.

jas wrote:
Already we know those are incorrect because you're adding some imaginary "mass" to the piledrivin' upper block, which, in your theory, is only rubble, and in reality is actually probably more like powder.

Yes, according to anti-Newtonian non-truthers like Frank Greening, there should have been somewhere more than 80 metres of rubble piled neatly by 9/11 fairies on each successive floor and adding to "pile driver" effect as crush-down occurred. Obviously there was no such mound of rubble at ground zero. Not even close. At least one person should have noticed that evidence.

Pants-of-dog

Fidel wrote:
Well I can certainly appreciate what the poster Heiwa says about Bjorkman's axiom:

Quote:
[url=http://heiwaco.tripod.com/nist.htm]Björkman's axiom[/url] regarding any structure says:

A smaller part of an isotropic or composite 3-D structure, when dropped on and impacting a greater part of same structure by gravity, cannot one-way crush down the greater part of the structure.

Heiwa is Bjorkman. Of course he's going to trumpet his own unsupported hypothesis. It would be better if he presented evidence for it instead of merely quoting himself.

Fidel wrote:
Quote:
"[url=http://en.wikipedia.org/wiki/Newton%27s_laws_of_motion#Newton.27s_third_... III:[/url] Actioni contrariam semper et æqualem esse reactionem: sive corporum duorum actiones in se mutuo semper esse æquales et in partes contrarias dirigi. "

" To every action there is always an equal and opposite reaction: or the forces of two bodies on each other are always equal and are directed in opposite directions. - Sir Isaac Newton, [url=http://en.wikipedia.org/wiki/Philosophi%C3%A6_Naturalis_Principia_Mathem... Naturalis Principia Mathematica[/url]

Newton and Kepler to the rescue.

wiki wrote:
Newton used the third law to derive the law of conservation of momentum; however from a deeper perspective, conservation of momentum is the more fundamental idea (derived via Noether's theorem from Galilean invariance), and holds in cases where Newton's third law appears to fail, for instance when force fields as well as particles carry momentum, and in quantum mechanics.

http://en.wikipedia.org/wiki/Newton%27s_laws_of_motion#Newton.27s_third_law

 

Fidel wrote:
Yes, according to anti-Newtonian non-truthers like Frank Greening, there should have been somewhere more than 80 metres of rubble piled neatly by 9/11 fairies on each successive floor and adding to "pile driver" effect as crush-down occurred. Obviously there was no such mound of rubble at ground zero. Not even close. At least one person should have noticed that evidence.

This is yet another one of those times when you claim that Greening or someone else says something ludicrous and you do not quote them, explain how it is inherent in their assumptions, or in any way present any evidence except your word that anyone said that.

Pants-of-dog

Fidel wrote:

Never mind Newton and Bjorkman. Your job as pseudo-scientific nontruther is to find a way around the established laws of nature. logical and mathematical reasoning. You haven't done that. And neither have NIST's fall guys Bazant and Greening -  two pseudo-scientific 9/11 fairies propping up crazy George Dubya's "war on terror" and ongoing war crimes still being perpetrated against desperately poor countries on the other side of the world.

Pants-of-dog wrote:
Greening is correct on that Newton's 3rd law is not universally applicable in the way that Chandler is doing so.

Bullshit!

None of this is an argument. You do not explain how anything I have said (or Greening or Bazant or the NIST for that matter) contradicts the laws of nature, logic or mathematics.

Nor do you explain how my refutation of Chandler is, as you so politely put it, "bullshit".

If you have any actual arguments that you would like to bring to the debate, I would be more than happy to discuss them.

Fidel

Never mind Newton and Bjorkman. Your job as pseudo-scientific nontruther is to find a way around the established laws of nature. logical and mathematical reasoning. You haven't done that. You haven't copied anything from Greening or Bazant that hasn't already been refuted by at least one of the 900 engineers for 9/11 truth on their peer reviewed web site, Journal of Engineering Mechanics, or elsewhere on the web. And neither have NIST's fall guys Bazant and Greening -  two pseudo-scientific 9/11 fairies propping up crazy George Dubya's "war on terror" and ongoing war crimes still being perpetrated against desperately poor countries on the other side of the world.

Pants-of-dog wrote:
Greening is correct on that Newton's 3rd law is not universally applicable in the way that Chandler is doing so.

Bullshit!

Fidel

I wrote:
Even when there are two objects(Bazant's rigid upper block C and massive but vulnerable to 9/11 fairies part A theory), and the two are made of the same materials and the two objects have different mass, the larger object always wins. - Fidel's axiom, which is borrowed from Anders Bjorkman observing Sir Isaac Newton as the original unobserved observer looking on.

Fidel

Pants-of-dog wrote:

wiki wrote:
Newton used the third law to derive the law of conservation of momentum; however from a deeper perspective, conservation of momentum is the more fundamental idea (derived via Noether's theorem from Galilean invariance), and holds in cases where Newton's third law appears to fail, for instance when force fields as well as particles carry momentum, and in quantum mechanics.

">http://en.wikipedia.org/wiki/Newton%27s_laws_of_motion#Newton.27s_third_...

So will you or Frank Greening be declaring a quantum theory of 9/11 collapse anytime soon? I declare a Laff-riot! Laughing

Pants-of-dog wrote:
Please provide the evidence for Szamboti's claims,...

What Szamboti said is that the upper block of the North Tower(WTC 1) actually did not tilt until several seconds into descent. I'm looking at [url=http://www.youtube.com/watch?v=xGAofwkAOlo]Etiene Suaret's video(filmed at 29+ fps)[/url], and I don't see any noticeable tilting until around the 36 second mark. Collapse begins at approx. 32 seconds. There was no significant tilt during collapse initiation of WTC1, therefore more of the kinetic energy should have been distributed through many more support columns of the lower floors than Greening or Bazant suggest was the case.

jas

Pants-of-dog wrote:

If I build a tripod, put it up, and then cut off one leg with an axe, it does not stay standing.

There. I have just disproved your claim about local asymmetrical damage only causing local asymmetrical collapse.

Not even analogous. I won't waste my breath.

pants wrote:
jas wrote:
As for the math you started showing us, pants, is there more to those calculations? Unless I missed something, you seem to only calculate the collapse of the first floor below the impact zone. Already we know those are incorrect because you're adding some imaginary "mass" to the piledrivin' upper block, which, in your theory, is only rubble, and in reality is actually probably more like powder.

What happens after that first collapse? And where is the loss of mass due to pulverization accounted for there and in each subsequent collapse? Thank you.

If you go back and reread what I said at the end of the...

I'll just quote it for you.

http://rabble.ca/comment/1159712/jas-wrote-You-have-never

Pants-of-dog wrote:

Please note that the kinetic energy for the upper block and the velocity for the upper block were faster at the moment of impacting the second lower floor than they were when the upper block impacted the first lower floor.

This shows clearly that the upper block crashed through the lower floors at ever increasing speeds.

What this means is that I took the smaller of the two upper blocks, calculated its kinetic energy and velocity right before it hit the first floor down, and then again right before it hit the next floor down.

If the kinetic energy and velocity were lower when it hit the second floor on the way down, it would have eventually slowed and stopped once it bashed through a certain number of storeys.

But since the kinetic energy and velocity were higher when it hit the second floor on the way down, that means that the upper block got faster and had more energy as it fell through each floor. So, it would have just gone through each lower floor with more KE and more velocity after each floor.

The calculations you base this conclusion on assume that a layer of rubble is the same as an intact floor. Not only that but that there is a layer of rubble, rather than the powderized concrete we saw exit the collapse waves in massive clouds all the way down. Not only that but that a layer of rubble will cause no resistance to the descending block of floors. Not only that but that a layer of rubble will somehow adhere to the top floor, increasing its mass, much like a sticky pancake.

You also haven't shown these calculations that lead you to your simplistic conclusion, and your conclusions don't follow logically. It seems you're hoping that by simply stating something, that we'll think it's true.

I asked you where the loss of mass is accounted for in your calculations. You would also need to account for transfer of momentum. I know you don't agree with the latter, but in the real world, i.e., to explain the collapses without any assumption of resistance being removed beforehand, you would need to. But at the very least, with your cartoon-like, two-dimensional model, you need to account for loss of mass at each step.

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