9/11 Physics: "You Can't Use Common Sense"

[eomer]

29. That was an intentionally extreme hypothetical for only a very narrow purpose.

It's purpose was to debunk a very specific claim and nothing other than that. The claim it debunks is that the lower part had to collapse due to the kinetic energy of the top part, no matter how that kinetic energy was applied. That claim is clearly not true, as demonstrated by cutting it up into many small parts and dropping them sequentially. Same amount of kinetic energy, no collapse, claim debunked.

But of course the different sections aren't really going to wait their turns. The hypothetical wasn't trying to say anything at all about how the real event would play out.

What seems to me would have happened in the real event is that the columns of the lower part would mostly pierce the upper part and the columns of the upper part would mostly pierce the lower part. Many of them would probably be broken by sideways and twisting forces and few if any would buckle by being subjected to the kind of straight on energy that the idealized model assumes. And I think the lower part would likely be crushed and collapse would likely occur. That's my own personal best guess as a layperson of what would have happened. But to demonstrate through engineering principles that it definitely would have happened has not been accomplished by Bazant. He has done some somewhat fancy calculations but hasn't demonstrated the relationship between those calculations and the real event. He assumed the relationship to be that of a limiting case but he hasn't shown why that has to be the case.