Heiwa, the relation between slenderness ratio and resistance to buckling is squared - so when you changed the values you were using by more than 3x, you admitted that the resistance to buckling was 10x lower than the original values you supposed. That's an
order of magnitude.
I could refer you to page 149 of
B.S. Benjamin's Statics, Strengths and Structures for Architects, which states:
Or, I could refer you to
Euler's formula specifically states that:
[qimg]http://www.efunda.com/formulae/solid_mechanics/columns/images/FcrB.gif[/qimg]
But,
the subject of this thread is your own ridiculous assertion that the Safety Factor for the loads in all of the steel in the WTC structure was greater than 300%. You can't back that up and won't ever be able to. The only reason that I bring up the above is that it so aptly demonstrates how you've failed to consider various failure modes, have done simply awful math whenever you provided any whatsoever, and simply can't be depended upon to know what you're talking about when it comes to building structures.
If you check again, you will see that I applied the Euler formula for the columns and suggest that you cannot really apply it to e.g. column 501, &c.
That the
perimeter wall columns have FoS>3 for static loads only, everyone seems to agree to. Reason being that the wall columns are also subject to dynamic loads when tower is subject to wind loads.
Re the core it should be clear that the outer core columns carry more load than the inner core ones (
http://heiwaco.tripod.com/loaddistribution.htm ) and that we disagree on the total core load carried. I suggest 16 500 tonnes, Urich 19 500 tonnes (and Bazant much more). You should also see that the wall columns carry different static loads at each floor as floor spans differ.
So my description contains many simplifications just to get a feeling for the structure and its redundancy.
Because, regardless of FoS of various elements, upper part C is virtually identical to lower part A. Evidently upper part C can never free fall on lower part A due to the 280+ columns in between that must fail, which is not seen on any video. What is seen on all videos is that part C suddenly telescopes into itself - it gets shorter - while nothing happens to part A.
But even if part C would free fall on part A, part C cannot crush down part A. Reason being that part A will destroy part C at collision contact. &c, &c.
The liers, suggesting that progressive collapse produces a crush down of structure, cannot produce any evidence for their fantasies. They assume that part C is rigid, which it is not. They assume that the bottom floor of part C cannot get damaged at impact but it is completely unrealistic. They assume that part C remains virtually intact while it ploughs down through part A at 0.7g, &c, but it is impossible. No structure type part C can plough through similar structure in part A due to gravity or any force. It is very easy to prove with sponges or lemons or pizza boxes or similar structures and the same result applies to parts A/C structures.
I find it fascinating that so many people at JREF are prepared to support the official, paranormal lies. They cannot even do it in a friendly way.
I am prepared to offer $1M to anybody that can produce a structure with two parts C and A of similar/identical structural composition, where, initially part A, fixed to ground, carries part C on top, and later by dropping part C on part A, gravity will then assist part C to crush down part A completely. Maybe JREF will sponsor this program like the other paranormal study? Similar rules will apply.
