Chemistry, Fire, and Collapse

[Apollo20]

Oh, and by the way, if you had taken the trouble to check, you would find that NIST do not use the mass of the entire building! Are you suggesting that NIST has been cheating?

If so I ask that you retract your statement and please think things through more carefully before you make such wild allegations and knee-jerk responses.

 

[rwguinn]

I am simply quoting from the NIST report (I give the reference) good sir!

Cherry picking quotes and deliberately misinterpreting them is intellectual dishonesty.
You know full well that the calculation was done backwards from the aircraft side of things. When applied to the aircraft, as you did, it makes sense to use a generalized acceleration, due to the relative physical dimensions of the two colliding objects. Using that same general value for peak acceleration on an object many times the size is wrong.
What you are trying to imply is that a 2 lb razor-sharp sword and a 2 lb baseball bat, when swung at a candle, both have the same effect.

 

[Apollo20]

Once again RWGUINN:

I quoted from NIST in response to a NIST quote from TAM; hardly "cherry picking". NIST consider the acceleration of the Tower AND the acceleration of the aircraft, and then appear to confuse the two.... is that my fault?

I am not trying to imply anything.... NIST IS!

 

[rwguinn]

Once again RWGUINN:

I quoted from NIST in response to a NIST quote from TAM; hardly "cherry picking". NIST consider the acceleration of the Tower AND the acceleration of the aircraft, and then appear to confuse the two.... is that my fault?

I am not trying to imply anything.... NIST IS!

Whatever. Since no where on the towers ever saw any acceleration higher than .25 g, then, I assume your zinc embrittlement is absolutely critical.
So, what is the mechanism for all that melted zinc to reach the fasteners at the ends of the floor pans, and with the floors sagging between the supports? And why did it decide to hang around there and soak into the fasteners whilst gravity was trying to make it go further down the structure.
Some sort of capilary action?

 

[Apollo20]

GWGUINN:

Nice attempt to dodge the question at hand.

I am asking you to apologize for the accusations of "intellectual dishonesty" and "cheating" or I am gone from this site FOREVER.........

 

[rwguinn]

GWGUINN:

Nice attempt to dodge the question at hand.

I am asking you to apologize for the accusations of "intellectual dishonesty" and "cheating" or I am gone from this site FOREVER.........

Don't let the door hit you...

 

[Crazy Chainsaw]

Here are some good links on the subject,
It is very interesting that the reactions that I speak of have been studied and found, just never before have all the reactions been found in one place in combination.
The reason it is not normally found in environments with PVCs and Zinc is because it requires rapid flame spread, a lot of fuel flowing to ignite the PVC Quickly, PVC has additives to prevent that.
A large hydrocarbon fire though would make the additives useless.
That is the Key rapid flame spread driven by Hydrocarbons that is how the experiment can be falsified.
If all the jet fuel was used up in the air blast then the reaction could not have taken place but if jet fuel started large fires on multi levels in the buildings, then the reactions are likely.
Please note I am still researching this Myself, I just told you Guys about what I found in trying to create the spheres that Is how I got into this honestly investigating how the spheres with zinc are formed.

http://www.ans.org/pubs/journals/nt/va-138-1-44-57

http://jchemed.chem.wisc.edu/JCEsoft/CCA/CCA3/MAIN/STEAM/PAGE1.HTM

http://www.corrosionsource.com/technicallibrary/corrdoctors/Modules/HotCorrosion/environments.htm

http://stinet.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA070312

http://www.icci.org/99final/pan2b-1%60.htm

Page 7 here,

http://72.14.209.104/search?q=cache:n1Ld60DaQg8J:www.svpindustries.com/pdf/pvc-and-fire.pdf+Hydrogen+combustion+temperatures+effect+on+steel&hl=en&ct=clnk&cd=72&gl=us



http://209.85.165.104/search?q=cache:n2MCf9pl9tsJ:www.fire.nist.gov/bfrlpubs/fire05/PDF/f05039.pdf+Hydrogen+combustion+temperatures+effect+on+steel&hl=en&ct=clnk&cd=116&gl=us

 

[JimBenArm]

GWGUINN:

Nice attempt to dodge the question at hand.

I am asking you to apologize for the accusations of "intellectual dishonesty" and "cheating" or I am gone from this site FOREVER.........

Oh, my, whatever will we do?
Really? Forever? Oh, dear!

 

[Crazy Chainsaw]

Whatever. Since no where on the towers ever saw any acceleration higher than .25 g, then, I assume your zinc embrittlement is absolutely critical.
So, what is the mechanism for all that melted zinc to reach the fasteners at the ends of the floor pans, and with the floors sagging between the supports? And why did it decide to hang around there and soak into the fasteners whilst gravity was trying to make it go further down the structure.
Some sort of capilary action?

I thought you were an engineer the bolted truss connections were flat level metal plates attached to the perimeter columns, all they zinc has to do is flow down from the wall studs.
It only has to embrittle the bolt heads, then they snap.
De-carbonation and Embrittlment by hydrogen at high temperature above 600c is more likely though.

 

[Crazy Chainsaw]

Don't let the door hit you...

Thanks for the sword analogy you just proved Apollo20's point, Check how hard aluminum oxide is compared to steel is it any wonder it cuts though steel with little resistance.

It is 9 on the hardness scale, iron is 4.5 steel is about 6, so the plane would tend to penetrate the buildings very well reducing the energy absorbed by the buildings.

 

[rwguinn]

Thanks for the sword analogy you just proved Apollo20's point, Check how hard aluminum oxide is compared to steel is it any wonder it cuts though steel with little resistance.

It is 9 on the hardness scale, iron is 4.5 steel is about 6, so the plane would tend to penetrate the buildings very well reducing the energy absorbed by the buildings.

Ok, lets go through this one more time.
The individual collisions within the tower were generally inelastic collisions, that is, there was a fair amount of bouncing around. The individual columns did not absorb the stuff hitting it--it bounced off.
The aircraft/tower collision, overall, was erssentially elastic: Most of the energy of the collision was absorbed by the tower. Some escaped--the fireball fuel, and relatively small chunks of the airplanes.
What apollo20 was implying was that the tower acted as a unit, and therefore did not see high acceleration. This is the baseball bat analogy.
The aircraft, being considerably smaller than the tower, had local effects that were much, much higher than the average. Just like the sword analogy, local areas suffered tremendous damage. In the candle, bonds were severed. In the tower, beams were severed, floors ripped up, and local high forces and therefore, accelerations.

 

[Crazy Chainsaw]

Ok, lets go through this one more time.
The individual collisions within the tower were generally inelastic collisions, that is, there was a fair amount of bouncing around. The individual columns did not absorb the stuff hitting it--it bounced off.
The aircraft/tower collision, overall, was erssentially elastic: Most of the energy of the collision was absorbed by the tower. Some escaped--the fireball fuel, and relatively small chunks of the airplanes.
What apollo20 was implying was that the tower acted as a unit, and therefore did not see high acceleration. This is the baseball bat analogy.
The aircraft, being considerably smaller than the tower, had local effects that were much, much higher than the average. Just like the sword analogy, local areas suffered tremendous damage. In the candle, bonds were severed. In the tower, beams were severed, floors ripped up, and local high forces and therefore, accelerations.

YOU have personally done impact studies as I have that confirm this or can I assume that your making an assumption?
Because I have put aluminum bullets completely though steel plating they tend to burn and penetrate not bounce off.

It is a reaction of the shock waves formed on impact breaking the oxide layer, causing aluminum to Oxidize rapidly.

Action reaction the fire ball exerted force on the building as it expanded. You can not say the buildings were unaffected by it.
Anyway I am done posting on this for now I have work to do, I want to see if I can get an a325 bolt

to last for more than 3.5 minutes under high temperature 900c hydrogen attack so far than seems to be the limit on them.

IT is actually fun to watch the bolts bubble out the carbon and transform into brittle iron while forming these unusual hollow metal iron spheres.

This is the last I am posting on this subject here, because I simply am wasting to much time in useless arguments with people and that time could be put to better usage.
I have kept my promise in informing Jerf as to how the metal spheres could have been created, and now my promise is complete. That work however has taken a new direction and I feel it is best to limit further comment and discussion until the work is totally complete.

 

[T.A.M.]

In a sense it was I who cherry picked, but I did so in response to the 0.25g quote from Apollo20. Now I quoted it, and simply asked him what he thought, which he did comment on.

Beyond that...is beyond me. However, they did say that as a result of this figure, they came to the conclusion that most if not all the ceiling tiles would have been removed, exposing the structure between floors to the fires...are you, Apollo20, suggesting this was an invalid extrapolation? If so, could you please explain what error they made in this. Thanks.

TAM

TAM

 

[rwguinn]

YOU have personally done impact studies as I have that confirm this or can I assume that your making an assumption?

Not recently, but during my career--including impact testin a Titanium turbine blade at 1000fps int various hardened steel armor plates. I even designed the gun to do it with.

Because I have put aluminum bullets completely though steel plating they tend to burn and penetrate not bounce off.
http://chainsawsanders.com/Thermite1.jpg It is a reaction of the shock waves formed on impact breaking the oxide layer, causing aluminum to Oxidize rapidly.

I certainly hope so. I have put lead projectile thru 1/4 inch plate, at a mere 1500fps, and copper jacketed lead through 1/2 inch steel at 3000fps. That was actually the point of my "Sword-baseball bat" analogy.

Action reaction the fire ball exerted force on the building as it expanded. You can not say the buildings were unaffected by it.
Anyway I am done posting on this for now I have work to do, I want to see if I can get an a325 bolt http://chainsawsanders.com/bolt1.JPGto last for more than 3.5 minutes under high temperature 900c hydrogen attack so far than seems to be the limit on them.

IT is actually fun to watch the bolts bubble out the carbon and transform into brittle iron while forming these unusual hollow metal iron spheres.
http://chainsawsanders.com/Ironbubble2.JPG

Yes, hydrogen embrittlement is nasty. It does need a source of hydrogen, however.

This is the last I am posting on this subject here, because I simply am wasting to much time in useless arguments with people and that time could be put to better usage.
I have kept my promise in informing Jerf as to how the metal spheres could have been created, and now my promise is complete. That work however has taken a new direction and I feel it is best to limit further comment and discussion until the work is totally complete.

And that is one way they could have formed. As R Mackey has pointed out, there are also lots of other ways they could have formed, including during the impact.