The 9/11 Forum

David B. Benson wrote:metamars --- Your link to the paper produces a pdf which requires a password to read. Is this something new? Do you have the password?

Here is another link to the paper, it does not require a password.

http://zkt.blackfish.org.uk/119/Simple_ ... s_WTC1.pdf

The author's replies to a couple of posts here are as follows:

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Statement from the author

@ Heiwa

Ryan Mackey in a white paper says that no peer reviewed paper has challenged the Bazant model of the collapse. This paper challenges the Bazant model Empirically. Please explain what you mean by rubbish.


@ David B. Benson

You say above..

"Don't want to waste my time reading garbage".

Clearly you haven't read the paper and instead are guilty of 'hand waving'. The Bazant theory of collapse could easily be said to be 'garbage' and this paper shows why it is garbage in the context of WTC1.

you also say...

"To solve the simplified problem of a resistive force of (1/3)mg, it is convenient to first "nondimensionalize", actually just change to non-SI units so that the descending mass m is 1, the height h is 1 and the force of gravity g = 1. Then due to the change in height by h=1, the available PE is 1, the KE is (4/9), the energy consumed by the resistive force is (3/9), leaving (2/9) to be consumed in other ways, such as setting cars on fire."

If the above is any indication of your 'Physics' it doesn't say much about your abilities. You and Bazant would rather obfuscate, and are clearly not people who want to shed any light on this issue.

Again from the above you yourself are 'physics challenged' because after change in height by h=1 the available PE is 0 and KE =1.

If you measure i.e. Empirically, the KE after the drop of 3.7 m we see KE =660MJ, the maximum KE due to transfer from PE at this point ~ 1 GJ, meaning ~ 340 MJ has been used up 'collapsing' the building. This means that Empirically after the 1st floor drop KE is nearer (6/9) and the remaining (3/9) is lost overcoming the structure leaving (0/9) to be consumed in other ways. Empirically this situation continues throughout the measurable initial phase of the 'collapse' or 12 floors of the 'collapse'.

Empiricaphobia ( to coin a term) a fear of Empiricism, characterises yours, Mackey's, Bazant's and NIST's approach to this problem.

I would love to debate you over this paper and the Bazant model, but unfortunately after 3 weeks waiting my account here has not been activated.

Best Regards
the author

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T_Szamboti wrote:Heiwa, this paper shows that there was insufficient energy loss in the falling mass to accelerate the masses below to the same velocity it was moving at, while also overcoming structural resistance.

I know. But the author, unknown, treats the initially falling mass - 'the upper block' - as a structure that is not damaged in contact with 'the lower block', which is not correct.

'The real upper block' is in fact weaker than 'the lower block' and would be locally damaged and arrested by 'the lower block' immediately at contact.

But we can evidently replace 'the upper block', 53 m tall, SG 0.2, by a steel plate, 1.35 m thick, SG 7.8, and use it as 'the upper block'. It has the same mass as before but is really solid (or rigid) and will not get damaged when it is dropped on 'the lower block'.

But I would not expect a 1.35 m thick, solid steel plate, mass 33000 tons, SG 7.8, dropped from 3.7 m above the object to crush to be able to crush down a 350 m tall structural assembly of steel columns/concrete floors! I would expect the steel plate to slide off the structure below in the process,e.g. due to unsymmetrical failures in 'the lower block', e.g. one wall failing before the other, etc.. But you are right. The steel plate should decelerate while compacting the lower structure.

Anyway, at the end such an imaginary process, you should find 'the steel plate' undamaged on top of or beside of what remains of 'the lower block'. Any trace of 'the upper block' afterwards?

According Bazant 'the upper block', e.g. the steel plate, will self destroy in a crush up! Actually, it will bounce in contact with rubble/ground, so at least the final part of the Bazant model is easy to prove wrong, assuming that 'the upper block' is rigid.

T_Szamboti --- Unfortunately that link also leads to a password protected prf (for me).

Anonymous author --- I apologize for the apparent inference that your paper is "garbage".

However, your analysis of the energy flows expending the PE of 1 from a displacement of height h=1 of mass m=1 at an acceleration of a=(2/3) does not fill me with confidence of your analytic abilities in physics. (It is the case that my prior post on this contains a blunder.)

T_Szamboti, any word on whether the author is going to try and join again, now that the admin problem is cleared up?

Hi

If you can't open the paper it might be because your pdf viewer is out of date, try Acrobat 9.

no_body --- The complaint is that the pdf is password protected. My Acrobat might be old, dunno, but I doubt that the latest version overcomes that protection.

newton wrote:T_Szamboti, any word on whether the author is going to try and join again, now that the admin problem is cleared up?

newton, the author is no_body so you can see from the post below yours that he now has access to the forum.

David B. Benson wrote:no_body --- The complaint is that the pdf is password protected. My Acrobat might be old, dunno, but I doubt that the latest version overcomes that protection.

A way around it would be to have someone e-mail the pdf to you.

The password should only prevent changes, anyone should be able to open, copy and print the document.

Sorry you're having trouble.

David B. Benson wrote:no_body --- The complaint is that the pdf is password protected. My Acrobat might be old, dunno, but I doubt that the latest version overcomes that protection.

The link at the top of the page...

http://zkt.blackfish.org.uk/119/Simple_CD_Models_WTC1.pdf

...works fine for me. No password required to download. PDF correctly protected from changes and cut&paste.

no_body: Welcome

femr2 wrote:

David B. Benson wrote:no_body --- The complaint is that the pdf is password protected. My Acrobat might be old, dunno, but I doubt that the latest version overcomes that protection.

The link at the top of the page...

http://zkt.blackfish.org.uk/119/Simple_CD_Models_WTC1.pdf

...works fine for me. No password required to download. PDF correctly protected from changes and cut&paste.

no_body: Welcome

Thank you. It works for me now.

And also a welcome to no_body.

yes, welcome to no_body, the guy who just made me use the shift key to make an underscore!

*SHAKES FIST*

i personally liked your paper, and i would curious to see your responses to some of the criticisms on this thread.

welcome, indeed!

Thanks newton. I'm glad you like the paper

Sorry it's taken so long to reply I've been away on another thread..... (thanks for your contribution BTW)

As for the responses to the paper, it is largely being ignored. Maybe we could have a quite discussion about why you liked the paper enough to say so, while no ones looking.

My Best Regards

I have a question for no_body regarding his paper.

In it you appear to be assuming that crushing phases (or Jolts, whatever you want to call them) follow a simple t^2 model. How do you justify assuming that any jolts must have been so symetric/patterened/evenly (insert appropriate descriptor here) spaced in the time domain?