Why a one-way Crush down is not possible

[Grizzly Bear]

Alien entity csn you explain how the 250-odd columns that till remained connecting the upper 10% of WTC1 to the lower 90% failed ? They represented about 85% of the original supporting columns after the plane had destroyed the other 15% . Did they kneel or did they squash down in a concertina fashion ? It's just that people say the top 10% 'dropped' but I can't see how.

They buckled.

 

[alienentity]

Alien entity csn you explain how the 250-odd columns that till remained connecting the upper 10% of WTC1 to the lower 90% failed ? They represented about 85% of the original supporting columns after the plane had destroyed the other 15% . Did they kneel or did they squash down in a concertina fashion ? It's just that people say the top 10% 'dropped' but I can't see how.

See post on 'What Did and Did Not Cause Collapse
of WTC Twin Towers in New York
Zdenˇek P. Baˇzant1 , Hon.M. ASCE, Jia-Liang Le2 , Frank R. Greening3 , and David B. Benson4
'

I suggest you email a qualified SE to discuss your pet theory. Prepare for a spanking.

 

[bill smith]

See post on 'What Did and Did Not Cause Collapse
of WTC Twin Towers in New York
Zdenˇek P. Baˇzant1 , Hon.M. ASCE, Jia-Liang Le2 , Frank R. Greening3 , and David B. Benson4
'

I suggest you email a qualified SE to discuss your pet theory. Prepare for a spanking.

I see you have no answer yourself to this very important question. I think they should come over here and gve me a spanking in public as an example to all the other Truth Movement people.

 

[Seymour Butz]

Alien entity csn you explain how the 250-odd columns that till remained connecting the upper 10% of WTC1 to the lower 90% failed ?

This explains why only 250C is needed for the core columns to buckle. Heat + time = collapse.


http://wtc7lies.googlepages.com/Bazant_WTC_Collapse_What_Did__Did_No.pdf

In that case, any steel temperature  150C sufficed to
trigger the viscoplastic buckling of columns (Baˇzant and Le 2008). This conclusion is further
supported by simple calculations showing that if, for instance, the column load is raised at
temperature 250C from 0.3Pt to 0.9Pt (where Pt = failure load = tangent modulus load), the
critical time of creep buckling (Baˇzant and Cedolin 2003, chapters 8 and 9) gets shortened
from 2400 hours to 1 hour (note that, in structural mechanics, the term ‘creep buckling’ or
‘viscoplastic buckling’ represents any time-dependent buckling; on the other hand, in materials
science, the term ‘creep’ is reserved for the time-dependent deformation at stresses < 0.50,
while the time-dependent deformation at stresses near 0 is called the ‘flow’; Frost and Ashby
1982).

 

[Seymour Butz]

I think they should come over here and gve me a spanking in public as an example to all the other Truth Movement people.

Didn't Heiwa already do that yesterday when he educated you about how it doesn't take "magic" for the upper block to fit inside the lower block if it's tilted? And again when he corrected your absolutely positive belief that the upper columns had to hit squarely on the lower columns?

Are you a masochist?

 

[Dave Rogers]

You, on the other hand, appear to me to be utterly convinced (or you seem to say you are) of the official 19 grumpy people conspiracy theory with absolutely no scepticism, or doubt in your own opinions, on show whatsoever.

Appearances are, in this case, deceptive. Like everyone else here on the debunker spectrum, I've studied the available evidence critically and painstakingly, and continue to study whatever new evidence the truth movement presents. I've yet to find a pro-inside job argument that, when viewed with a small fraction of the level of skepticism its proponents would claim to bring to the well-understood narrative of an al-Qaeda terrorist attack, doesn't collapse into its own footprint at near-freefall speed.

Dave

 

[twinstead]

Appearances are, in this case, deceptive. Like everyone else here on the debunker spectrum, I've studied the available evidence critically and painstakingly, and continue to study whatever new evidence the truth movement presents. I've yet to find a pro-inside job argument that, when viewed with a small fraction of the level of skepticism its proponents would claim to bring to the well-understood narrative of an al-Qaeda terrorist attack, doesn't collapse into its own footprint at near-freefall speed.

This is key. So many truthers come on this forum and declare that it is they who are the skeptical ones and we are the sheep. This couldn't be farther from the truth. The body of evidence that supports the "Official Story" is HUGE and compelling, and most of us are able to view it along side the evidence presented by the truth movement it in a rational and objective way.

Knowing this about us, to me there's nothing more irratating than a mindless, irrational ideologue drone who has the cajones to call ME, or people on this forum, a sheep. Yea, I'm SURE we are all just believing what we are told about 911, aren't we? I mean truthers' evidence is SO compelling, and the evidence for the "official story" is so slight, it's the only conceivable reason we could possible disagree with them, right?

 

[Heiwa]

Do you agree with Tony's figure that the lower block must resist a 31G hit in order to halt the collapse? This is what your "bounce" statement is based on, correct?

So to use Tony's model of the 30 legged/100lb table with a FOS of 3, you are saying that the table would be able to take 3100lbs without breaking/buckling the legs.

I guess this is where your belief that if you dropped the upper block from 2 miles up, the lower block would survive comes from, eh?

Also, can you explain to us why you say that the upper block would bounce, and not progress, and yet still claim on your website that entanglement would halt the collapse? Aren't they contradictory models?

A tennis ball weighs 0.058 kg and is served at 55 m/s velocity and thus has energy content 90 J. The opponent hits the ball back at 45 m/s. Fast game!
The total change of velocity of the ball was 100 m/s but how long did it take?
Say the ball was in contact with the racket 0.05 s. The forces applied on ball and racket corresponds to 200G.
And the racket and ball resisted it.
All answers to your questions are on my web site. For tennis there are other sites. But the principles of two objects contacting each other and forces involved are always the same.
Re something dropping from 2 miles on anything - yes, at contact forces are same between something/anything, which was the answer. Something frequently does not survive, though, but anything often remains. Which was not the question/answer.

 

[Heiwa]

Heiwa's current red herring is based on the false premise that the outer columns didn't bow and fail as seen on the video evidence.

As it is based on a false assumption, easily demonstrated as such, it must be discarded as nonsense.

Outer columns fail as seen on video? To initiate drop? Pls provide evidence! Fail = in at least two parts.

 

[WildCat]

Hmm.... you've "forgotten" about this, already?



Seems to work pretty well. Just my non-engineers opinion, but I'd guess that the reason that collapse looks remarkably to the WTC collapses is that it was remarkably similar: weakened columns were pulled out of the way, and gravity did the rest. And neither seems to be very similar to a stack of pizza boxes.

Heiwa? Heiwa? Heiwa?

Is this thing working?

Topic is Why a one-way Crush down is not possible. It is not a bad idea to know why.

Heiwa? What does the video show?

Heiwa?

bill smith?

Any truther?

Bueller?

 

[Seymour Butz]

The total change of velocity of the ball was 100 m/s but how long did it take?
Say the ball was in contact with the racket 0.05 s. The forces applied on ball and racket corresponds to 200G.
And the racket and ball resisted it.

But the racket/ball are designed for these forces, right? Presumably they have a FOS of >200.

Were the towers designed for 31G? Do they have a FOS of >31?

 

[tsig]

The disintegration of the psyche is such a fascinating thing to watch.

Dave

Do you think it is an inside job?

 

[Heiwa]

Heiwa misrepresents Bazant. I have the pdf 'What Did and Did Not Cause Collapse
of WTC Twin Towers in New York ' published in the 'Journal of Engineering Mechanics ASCE , Vol. 134 (2008), May 27, 2007
Revised June 22, December 15, 2007, and March 31, 2008

It's not two days after 9/11.

And Heiwa misrepresents the main thesis of the paper, which clearly states on page 3 'The gravity-driven progressive collapse of a tower consists of two phases—the crush-down, followed by crush-up (Fig. 2 bottom).'

Crush-down AND crush-up. Well established and covered in Bazant and Verdure 2007, pp. 312-313.

Again, not two days after 9/11, as Heiwa insists. By my reckoning, 2007 and 2008 are some 6 and 7 years after the event.

And Heiwa still is at a loss to account for the video offered in post 485 by WildCat.

Heiwa, you're busted bad, dude! Your theories are epic fails contradicted by the most basic evidence from 9/11.

Stop flogging this dead horse already. You've lost.

??? Bazant was out very early 2001! e.g.

‘‘Why did the World Trade Center Collapse? - Simple analysis’’ handed in 9/2001 to ASCE and published in Journal of Engineering Mechanics,

Bazant, Z. P. 2001 ‘‘Why did theWorld Trade Center collapse?’’ SIAM News, 34(8)!, 1, 3.

Etc. Very quick job!

 

[Seymour Butz]

[qimg]http://heiwaco.tripod.com/WTC1slicea.GIF[/qimg]

I have a question about this-

In figure D, you rightly have the upper part at an angle, although I would give it a greater angle. You also say that these core columns would"rub" against each other. I agree.

But as your illustration shows, these core columns are now unbraced. Wouldn't these "rubbing" columns break at the welds and/or buckle due to their increased unbraced length and drop?

And when these welds break, wouldn't the floor ends attached to them also drop?

Therefore rendering your "arrest from friction" argument invalid, since the floors are now dropping at the same rate as the columns?

Didn't you already argue that core columns from both the descending block AND the lower block would break off?

You've invalidated your own argument yet again, senor....

 

[Heiwa]

But the racket/ball are designed for these forces, right? Presumably they have a FOS of >200.

Were the towers designed for 31G? Do they have a FOS of >31?

You do not design steel tower structures for impacts loads. Just static (weight) and dynamic (eg wind) loads. Impacts you have to study separately. But evidently a steel element can resist >200G. You agree a steel element is stronger than a tennis racket/ball? That's why I mentioned tennis rackets. Can resist big forces. But just for 0.05 seconds. Same for the hand holding the racket ... and the elbow furher away.
Thus, WTC 1 lower part A should easily resist upper part C dropping on it = bounce. It is all described at my web site. Impact speed was just 5.82 m/s.

 

[Heiwa]

I have a question about this-

In figure D, you rightly have the upper part at an angle, although I would give it a greater angle. You also say that these core columns would"rub" against each other. I agree.

But as your illustration shows, these core columns are now unbraced. Wouldn't these "rubbing" columns break at the welds and/or buckle due to their increased unbraced length and drop?

Load is reduced in columns. Nothing can break them. And they are still braced by damaged floors. They are the strongest elements in the structure.

 

[Seymour Butz]

You do not design steel tower structures for impacts loads.

So why did you use a tennis ball/racket?

But evidently a steel element can resist >200G.

Who cares if a piece of steel can resist 200G. In this case, you must prove that the lower parts/assembly can resist 31G.

Thus, WTC 1 lower part A should easily resist upper part C dropping on it = bounce. It is all described at my web site. Impact speed was just 5.82 m/s.

Ok, so now you've got the beginnings of proving your theory. Now prove it with maths. What would be the loads seen by the lower columns? Given a FOS of 3, are they strong enough to resist buckling?

 

[tsig]

Full blown case of ASDES and endless repetition of bad ideas....that's Heiwa in a nutshell.

It's 2009, time to move on and let those people R.I.P.

Time to find another claim to fame buddy. Your nonsense is helping no one.

He seems to be under the delusion that if you post something often enough on the internet it becomes true.

It's becoming more and more common. I think it is the result of to much time at the computer til what you see on the screen becomes reality.

Or it's just arrogance+ignorance=woo(tsig's formula)

 

[Seymour Butz]

Load is reduced in columns. Nothing can break them.

Forget load. Why wouldn't the welds break from side impacts?

And they are still braced by damaged floors. .

Braced how exactly? The floor beams in the core ares are gone. How can they brace the core columns if they're gone?

 

[WildCat]

Isn't it fascinating how all the resident truthers (especially Heiwa) manage to avoid commenting on this video:



I'll be sure to post it in every thread Heiwa pops his head in. On every page. Because it shows exactly what Heiwa claims is impossible.