Moderated Steel structures cannot globally collapse due to gravity alone

BenBurch said:
Correct. I am drawing the distinction carpenters draw between timber and lumber. Lumber is generally thin enough to burn through or reach failure before the limiting properties kick in.
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what burns through faster in your home fireplace, a log of wood or the steel grate that supports the wood?

that one was easy enough...NEXT!
 
Digging out that evidence of the Space Elevator design work, Bob? It's all a bit quiet over there, as they say.
 
bob the analyst said:
is this like one of those self stroage bins?

I think that you need to look at the big field here, not a shed like structure, we're talking massive steel beams and girders of immenses size and strength, steel specifically designed and tested to withstand forces 10 times greater in heat and energy that the steel faced in the wtc.

think big, real big, you can do it, ask for help and direction
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I am talking about a steel framed warehouse. If it made of steel framing then according to you it cannot collapse because fire does not affect steel. This building proves you wrong.

Or are you admitting that fire can, in fact, affect steel so badly it collapses?
 
Bob; I do believe you missed a post from this fellow
Sunstealer said:
Originally Posted by bob the analyst
care to explain why the NIST failed to use microscopic techniques, such as an SEC, scanning electron microscope in their analysis? There's still no evidence of martensiting effect, yet they claimed yield and strenght loss and tensile and plasticity and that can not happen with out showing and verifying a martensiting, plus several others, then of course you have to compare it against the original core samples from the original steel heats for a comparison
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hahahahahahahahah Martensiting. Omfg you buddy are hilarious - I don't know whether to put you on ignore or risk lowering my IQ reading such drivel, as a metallurgist I dunno if I can take the stupid anymore, but I do need to refute this for the benefit of everyone else.

I've never heard the term "martensiting" before, because it's not used. I've got text books going back to the 1960's and it's not in any of those so I googled it and got 30 results! LOL I believe he's trying to refer to the transformation of austenite to martensite. i.e the martensitic transformation.

However it's plainly obvious that he doesn't understand what martensite is or how it is produced (rapid cooling from the austenitic phase via a diffusionless, shear transformation producing a metastable BCT structure - with usually Ms around 220°C and Mf around 90°C but this obviously varies with composition).

Firstly there isn't any martensite present in A36, because it's not quenched - the predominant microstructure for A36 (rolled) steel is elongated or banding of pearlite and ferrite (due to rolling). Can't possibly contain martensite and the material specifications don't require it. It's a silly thing to need to do for a structural steel because it would add huge cost.

Secondly, if he is claiming that the fires couldn't reach the AC3 temperature then it would be impossible for any martensite to form because in order to produce martensite you have to quench from above the AC3 temp - he's arguing mutually exclusive points and debunking himself!

Thirdly, even if the fires heated steel to 1000°C the resulting cooling rate would not be quick enough to transform the micro-structure to (a percentage of) martensite, therefore the idea of claiming "no martensite in the cooled steel microstructure indicates yield and strength loss" is a red herring.

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Fourthly, and this does make me chuckle, the whole point behind quenching to martensite is that the resulting structure produces a higher yield point and a stronger steel, the opposite of what BTA claims! It does this at the expense of ductility (it's brittle) and therefore it's common practice to temper martensite.

There is absolutely no reason to look at original samples from heats, the likelyhood is they are long thrown away. The mill(s) would have produced steel to an accepted international or American standard. Also the only thing you have to do is perform metallurgical analysis on specimens taken from WTC steel that was not affected by fire. This was also done and the results conformed to the relevant material specifications - this is in the NIST report, I've read that very section.

SEM including EDX/EDX analysis was also carried out in the metallurgical analysis (although it's not the be all and end all)

http://911research.com/wtc/evidence/metallurgy/WTC_apndxC.htm

I believe the interweb term is PWNED or OWNED. I await your answer, sidestep, ignore, goal-post move with hilarity!
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bob the analyst said:
what burns through faster in your home fireplace, a log of wood or the steel grate that supports the wood?

that one was easy enough...NEXT!
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Keep digging, son. Incidentally, far be it from me to point to your reading comprehension issues but you'll see that the difference in fire performance characteristics between wood and timber (UK) / wood and lumber (US) were discussed over a page ago.
 
phunk said:
You can't just say that and make it true. You have to find the vertical component of it's speed, know its terminal velocity, and how high it fell from, to determine if it had 0 vertical velocity when it left the building.
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What part of "more or less horizontal" don't you understand?

You are ignoring the point which is:

The object was traveling away from the tower at 72 mph.

The 'flicker factor' is fatally flawed. tfk's analysis does not provide a way for the potential stored energy to be applied to hurling a frame section away from the building.
 
bob the analyst said:
I guess that you have what experts call reading dyslexia, basically reading comprehension, I said that this kid designs buildings and is an architect as MUCH AS I DESIGN SPACE ELEVATORS--IT WAS SARCASM-MAYBE IT WENT OVER YOUR HEAD-YES, IT DID GO OVER YOUR HEAD
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Ahhhhww, is diddums upset?

I'll have that apology, or evidence you design space elevators. Take your pick, loser.
 
funk de fino said:
I am talking about a steel framed warehouse. If it made of steel framing then according to you it cannot collapse because fire does not affect steel. This building proves you wrong.

Or are you admitting that fire can, in fact, affect steel so badly it collapses?
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do you have the Scottish version of their NIST report handy, let's compare notes
 
That's no way to talk to Heiwa's kid brother. Bully
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Aye, he might get his dad on to me.

Come on, Bob. You've been caught out. Admit it. One of us designs tall buildings for a living, and it ain't you.
 
Architect said:
No, Bob, you're trying to evade the point.

You tried to call me out on professional qualifications and experience. Specifically, I design and construct tall buildings for a living. And you, it would appear, don't.

Now let's be quite clear. Are you absolutely sure about this? Think carefully before you answer, because otherwise you're going to have to show that you design space elevators for a living.
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Yeah, he's going to continue this dance. Note how whenever confronted with specifics, he pulls something out of his Google-fu and puts it up as if he knows what he's talking about; that's his way of avoiding substantive commentary. He's yet to confront his incoherence about fireproofing, and unfortunately, I don't think he's going to recant his accusation. Quite simply, I think we have a new space elevator designer on our hands.

Hope he picks out the right paneling for the walls; that faux wood stuff is just so grating nowadays. :rolleyes:

---

On a more substantive point, Architect: You and others have mentioned before that the European building codes have been modified to take into account the findings from the NIST Reports. I'm having trouble locating the modified ones online, mostly because I'm no architect or engineer, so I don't know what the hell I'm doing when I try to look this stuff up :boggled:. Would you be able to give me a specific reference on where I can find those codes? Even if they're not online, I work at a university, so I could always find a way to look them up somehow.

Yes, I realize that the code itself isn't going to say directly "This change is because of the NIST study". In fact, I realize that the code is probably going to be miserably dry reading. I would still like to know which code(s) it/they are, though. If you happen to know off the top of your head; I don't want to turn this into anything more than a quick lookup for you, so if it requires actual research, don't worry about it right now.

And also: I'm not doing this for bob the talker; such information would be utterly lost on him. Swine understand pearls better. No, rather it's just for my toolbelt whenever the information is applicable.

Thanks!
 
still no wonderful musings on testing parameters from the architect that I challenged him to supply, you can't believe how shocked we are here by your lack of a response

oh where oh where is the architect hiding this vital and much needed info that will save his credibility?


did you guys read my witty sarcasm in that post?
 
bob the analyst said:
do you have the Scottish version of their NIST report handy, let's compare notes
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You know, the funny thing about that comment is that it's essentially meaningless.

Bob, the fire performance of structural steelwork is not a matter of debate but rather one of fact. We know that it's susceptible to failure under normal fire loadings. Toere is more research than we can shake a large stick at, and if you insist in pursuing this frankly ridiculous course of action then you're going to look like an even bigger fool.

Now, I was waiting for some space elevator designs from someone. They should be along in a minute....
 
bob the analyst said:
what burns through faster in your home fireplace, a log of wood or the steel grate that supports the wood?

that one was easy enough...NEXT!
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The steel grate was over designed for just that application. When cool you can literally park a pickup truck on it. Park that same weight on it and subject it to that same fire at it will lose strength and collapse.


More on steel strength and the effects from heat.

http://books.google.com/books?id=Fs...7MHXDw&sa=X&oi=book_result&resnum=8&ct=result
 
bob the analyst said:
where did you get the idea that stress relief of steel, which has many areas and techniques-processes we're talking about here, was a test in and of itself?
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From your post Bob, just explain in your own words what stress relief is please...and how it relates to the construction of the WTC complex.

Were some of the joints heat treated? Yes or no.
Were all of the joints heat treated? Yes or no.

If they were what was the purpose?

You raised the issue of stress relief Bob, not me.
 
ElMondoHummus said:
On a more substantive point, Architect: You and others have mentioned before that the European building codes have been modified to take into account the findings from the NIST Reports. I'm having trouble locating the modified ones online, mostly because I'm no architect or engineer, so I don't know what the hell I'm doing when I try to look this stuff up :boggled:. Would you be able to give me a specific reference on where I can find those codes? Even if they're not online, I work at a university, so I could always find a way to look them up somehow.
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The one you'll be specifically interested in is/are the Eurocodes. Unfortunately, they cost a packet. These were then adopted into national standards across Europe progressively. In particular they place emphasis on the need to design in sufficient redundancy to limit the risk of what they term "disproportionate collapse" in the event of an event such as fire or explosion.

If your work subscribes to one of the online information archvies such as Barbour then you should be bale to track down a copy. I think - but don't quote me on this - that it was part 3. If that fails, let me know and I'll speak to one of the engineers on my own projects.

And also: I'm not doing this for bob the talker;
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Hey, the guy must be a genius, he designs space elevators for a living.
 
A W Smith said:
Bob; I do believe you missed a post from this fellow
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good for you, great find, do you understand wht this chart means and what it says...you see, the steel would have to start looking in this fashion as it broke down, in an element basis, yet the NIST reports what...all areas and facets have to have shown the steady and progressive breakdown for steel, joint, truss and member failure


I might be getting through to you, if you take the time to read, analyze and allow you, not force you, to understand


this is what is called red x, you see a failure, you ask why and in how many ways the failure could occur, then you prove that failure out in testing and analysis...repeatedly...with all tenets of the same chemistry of the steel as well as the grades involved


I know this is very deep and very technical for a layman or someone like you that is very inexperienced in steel workings, design, chemistry, but I still have hope to straighten and enlighten people like you that have a biased and tunnel visioned approach to the wtc collapse

helpful Bob
 
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