Originally Posted by GlennB
What I said discussing something from a theoretical point of view was:
"No - not really ... even after a two mile drop and a plenty of energy/forces at impact. As the upper part C is smaller (1/10th of A) and can absorb less strain energy than the lower, bigger part A on ground, the upper part C is destroyed completely before part A is totally destroyed. After part C is totally destroyed it does not apply any force on what still remains of part A.
You see, you cannot destroy a structure by dropping a piece of it on the whole.
But if part A had enough strain energy and was elastic enough to absorb all energy involved at the contact and that also part C could absorb that energy (or half of it! and no local failures develop), then part C would bounce - maybe a mile and 3/4 up. Big bounce. "
You see, Glenn B, you have to quote properly!
Actually - according to NIST and Bazant & Co the drop height doesn't matter as they assume that the upper part C is rigid during crush down and does not get affected at all. It remains intact! But after part C has crushed part A, part C is not rigid anymore ... and crushes up = gets destroyed by contact with the ground (or the rubble of part A). Quite unscientific. Part C cannot be rigid at one moment and not rigid another but that is the ONLY way NIST and Bazant & Co can explain the crush down of WTC 1. According basic structural damage
analysis (and a small drop 0.5 or even 3.6 m) part C of WTC 1would just get stuck on top of part A! Both parts C and A would be damaged at the interface and the damages would mirror each other.
Had the structure been more like a sponge part C (a small piece of sponge) would just bounce on part A (the bigger piece of sponge) ... and that would be it.
NIST and Bazant & Co cheat: part C is assumed to have a different
(rigid) structure than part A (not rigid) and then, OF COURSE, part C can crush down part A. Cheat? It is criminal falsification of a technical report or model to explain something.
It seems I have won the discussion about the subject of this thread. Only you, Architect and Gravy (of course) try in vain still to change the subject. So I will not respond to your nonsense any longer. Real comments are of course still welcome.