• Quick note - the problem with Youtube videos not embedding on the forum appears to have been fixed, thanks to ZiprHead. If you do still see problems let me know.

Bazant in a nutshell

ergo said:
DGM, what field are you employed in?
Click to expand...

DGM said:
I'm a general contractor/ builder. Why do you ask?
Click to expand...

What do you do?

I'll add:

I've owned my business for thirty years and have built hundreds of houses and commercial buildings. I can read drawings (and build directly from) and do material take-offs. I deal on a daily basis with engineers and architects.
 
Last edited:
ergo said:
Please cite where he makes these comments or conveys this meaning in the paper referenced.




The best possible scenario for the buildings not to globally collapse was reality. Bazant's scenario was fantasy.
Click to expand...

Um, in reality they collapsed. The model wasn't to recreate exactly what the collapses looked like but rather to study the math behind the collapses.

What do you do for a living? You must be a top engineer to claim how wrong a top engineer is.
 
DGM: can you give us an example in your field where you are working from a model that is not required to represent reality or an outcome that would work in reality ?
 
I posted before your edit.

ergo said:
Let's put it this way, DGM: can you give us a real life example in your field where you are working from a model that is not required to represent reality or an outcome that would work in reality ?
Click to expand...

Yes I can.

I use a lot of laminated lumber now. This is tested to destruction in order to determine it's working (reasonable) properties. These members will never be pushed to these limits because design is based on what was found to be destruction. The distruction was the model. Now design is based on what will never be reality.

Do you understand?
 
You don't understand the question. The destruction is an outcome that is based on reality. It could happen. That's what materials standards are for.
 
ergo said:
You don't understand the question. The destruction is an outcome that is based on reality. It could happen. That's what materials standards are for.
Click to expand...
How do you determine material standards without models? We don't build it and see what happens.

I hate to tell you, you don't understand the question.

Did you miss me asking what you do?
 
ergo said:
DGM: can you give us an example in your field where you are working from a model that is not required to represent reality or an outcome that would work in reality ?
Click to expand...

Electrical schematics are models of how circuits work but they don't represent the physical layout. That's when you need the wiring diagram. :)
 
Justin39640 said:
Electrical schematics are models of how circuits work but they don't represent the physical layout. That's when you need the wiring diagram.
Click to expand...

Which is required to represent a workable reality, correct?

Not sure what part of this bedunkers aren't understanding.
 
Justin39640 said:
Electrical schematics are models of how circuits work but they don't represent the physical layout. That's when you need the wiring diagram. :)
Click to expand...
And they are often pushed to un-realistic levels to prove the design. This is a model that does not represent reality.

I thought of you the other day*. My fork truck shorted out the speed controller. I sounded like a bomb went off. :D

IIRC your work on this sort of thing.
 
Justin39640 said:
Electrical schematics are models of how circuits work but they don't represent the physical layout. That's when you need the wiring diagram. :)
Click to expand...

I'm pretty sure ergo has me on ignore, because I presented two models where the purpose is to understand the underlying mechanism and not recreate real life. I think an electrical schematic is another good example.

We also occasionally create models using Crystal Ball at work, to get at the underlying model of a failure or a faulty process. The model never Exactly recreates a scenario. Sometimes it is also used to predict probable outcomes and establish risk.
 
ergo said:
Which is required to represent a workable reality, correct?

Not sure what part of this bedunkers aren't understanding.
Click to expand...

You are saying a model should represent reality exactly. Schematics don't do that. They just show the connections. Sometimes they can really throw you off while trying to track something down cause of that if you don't keep that in mind.

From a crappy Radio Shack basic electronics textbook: "The atom may be pictorially or symbolically represented by a model that resembles our solar system... This atomic model was proposed by Danish physicist, Niels Bohr, in 1913. Quantum mechanics have shown that this model is not exactly correct, but is still useful in visualizing the atom."
 
It's OK. I'm just now realizing why bedunkers think Bazant's is a model of reality. :)

To argue further on this path would get into discussions that have occurred countless times here and elsewhere. It also gets complicated for this discussion because not only does his model not represent what happened, but it's also not workable in any reality based on Newtonian physics, as others have already pointed out (and are much better equipped to argue than I am.)

For now, I just want to get back to the point that his simplifying assumptions go far beyond where simplifying assumptions should normally go -- writing two days after the event and before any investigation had been conducted -- and seem instead to seek to provide a thorough explanation. There is and was no need for this. There was no need to put "Rapid Communication" at the top of his paper. This wasn't discovery, this was hypothesis. Was he afraid engineers might come to different conclusions? What was the hurry?
 
Last edited:
DGM said:
And they are often pushed to un-realistic levels to prove the design. This is a model that does not represent reality.

I thought of you the other day*. My fork truck shorted out the speed controller. I sounded like a bomb went off. :D

IIRC your work on this sort of thing.
Click to expand...

Ha! That is what I work on. I'm considered an expert in motor control. Doing it for 17 years. A 500 amp power circuit shorting will always sound like a bomb going off. The must have planted thermite in the SCRs (or IGBTs, mosfets, etc) :D
 
You must log in or register to reply here.

Back
Top Bottom