I understand where you're coming from... but you misunderstood what I was trying to convey. I was assuming the most bare basic model you can use to do the calculation to explain the concept that, the more slender a column the less that column can carry. It had to do with Heiwa's model having the debris be contained in 15 stories of unsupported column legth. But I don't think that misunderstanding matters all that much at this point... having looked at my post and looking at the posts that came before it (specifically yours) I feel like an idiot I apologize for making a rather insignificant point that was much more professionally explained before hand. I was in the wrong there, and apologize for any confusion that post lead to.
Newton I nevertheless thank you for retrieving the information of the columns used in the trade center. I don't have the handbook with the information on those column classifications, I only have them for the wide flange steel members which essentially means that even if the calcs I wanted to attempt had much of an impact to make I wouldn't have otherwise had the right information to work with.
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Griz,
Hey, no problemo, amigo. I'm sorry that I missed your point.
And there is zero reason to feel like an idiot. In fact, quite the opposite.
The fact is that you did two things in succession that were perfect.
First, you tried to understand things in your own terms. This forces you to examine things in your mind, to really think about the details. This is far better than just taking someone else's word for things.
Then, you asked for help. And listened. This is the step that appears impossible to twoofers. The fact is that there are lots of different ways to look at things. Frequently only a small percent of them end up being really useful. And this is essentially what engineering is: a weeding thru the numerous ways to try to understand things to keep only the useful ones.
I've learned lots of things here. Especially in the specialty of collision & impact. I've never worked in a field that required this. Same rules apply for me: Try to figure it out myself based on first principles (i.e., the science), and then find out how the experts do it (i.e., the engineering). Inevitably, there will be factors that you are unlikely to predict that dominate the issues.
tom
PS.
The gist of my message in numbers:
Putting real numbers to the idea that I was trying to get across, this fellow (Gregory Szuladzinski) estimates that "This results in 78.26 tons supported by one outer column".
http://www.civil.northwestern.edu/people/bazant/PDFs/Papers/D25%20WTC%20Discussions%20Replies.pdf
(While I don't accept this guys overall conclusions, a quick check tells you that
this number, that he says he got from FEMA, is reasonable, putting the weight of the upper 15 stories at about 48 Kiloton.)
Considering factors of safety, this tells you that, properly assembled & cross-braced, the column was capable of supporting about double this value, a total of about 150 tons, properly distributed at 1 story intervals.
To show you the huge discrepancy that can exist between misdirected theory & practice, my "feel" tells me that, without cross bracing, this column was capable of supporting ZERO load. That, in a stack, bolted together with 1" diameter bolts, a fifteen story (5 assembly) stack could not have stood on its own without toppling. (This is the question that Heiwa refused to answer.)
I apologize for making a rather insignificant point that was much more professionally explained before hand. I was in the wrong there, and apologize for any confusion that post lead to.
