NIST did not study the "collapses", only the events leading up to them. You know that Gravy, stop pretending otherwise.
And of course the reason for that is that they determined that earlier work examining the collapse in the more general terms of energy being coupled from floor to floor was correct.
One of the nice things about science is you don't have to reinvent the wheel. You can cite earlier work that has been independently verified, and go on from there.
They went on to find the likely initiating factors. That is, the sequence of failure that matched the data of this wall bulging, that antenna tilting, windows cracking... Once you get to the point where the collapse has initiated, and the energy coupled from floor to floor is enough that it will continue, there are a couple of things to consider:
The collapse is immensely chaotic, and there are many different possible failure modes, all of which continue the collapse.
The dust cloud prevents getting any data which would allow you to differentiate between the different failure modes, even if you were inclined to.
And from NIST's point of view, why bother? NIST doesn't do this sort of research to satisfy conspiracy theorists, it does it to see if there's any way to improve the safety of structures. Once the structure has failed, and you can calculate that it must continue, you're done. The previous work showed that the collapse had to continue, even if it did not have a millisecond-by-millisecond timeline of which structural member failed when.
No, there are many observations for which I have not heard a scientific explanation. Posting pictures of kittens does nothing to further science.
What about the round holes? The unburned paper next to the exploding cars? THe exploding firetrucks? THe melting car parts, what is the explanation for this? WTC3, where did it go? What about the south part of WTC4? Please describe the mechanism by which WTC6 ended up so hollowed out. What about the "shooters", what causes this phenomenon?
You need to read the thread more carefully. This has all been explained. And frankly, if this stuff is confusing you, you need to get out in the real world and build some stuff, and have it break, and be around a real fire and see how it works. No one is spending much time trying to explain this stuff because the events are not anomalous.
And where is all the missing mass?
Where's any evidence for "missing mass"? How much is missing, and how do you know?
Where are the floor assemblies? Where is the core of WTC2? It was standing after the colllapse, 700 feet of it, then, it disappeared. Where did it go?
Missing from where? Where should they be, and what condition should they be in? With regard to the core, what should have happened to it, and why? What does the difference between what you think should have happened to it, and what you can show did happen to it, indicate, and why?
Are there records of the steel that supposedly went on barges to China? Not that those couldn't be fudged, but, do they even exist?
Why don't
you find out? How long should people keep records to satisfy your curiosity? If you're not going to believe any answer you get, why ask?
Is "drywall dust" really your best explanation for the dense white and brown dust which is churning out of steel members continually as pieces fall? I certainly don't buy that one. This looks as though the ends of the steel columns are belching smoke. What would explain this?
Somewhere on the web, there's a video taken by someone blocks away from the WTC, being overtaken by the dust cloud. In seconds, the lens is so dusty that the remainder of the video is mostly useful as soundtrack, because the images are just gray blobs.
That's blocks away, after the dust has spread to
hundreds of times the volume of the towers. I think the dust at the point of the collapse, being "strained" through the openings of the prefabbed column sections as all the air on several floors is escaping through them, would be
much denser, and would load them up with quite a lot of dust. I know, from driving on dirt roads behind other people, that the back of a truck will shed dust for quite awhile even after you get back on the paved road. Certainly longer than the few seconds it took each piece to fall. And the back of the truck just got dusty. It wasn't sandblasted with a dense load of dust.
However, I don't insist on that explanation. I have no idea if that's an "official" explanation or not. It's simply speculation on my part. I could be wrong.
I like it because, unlike a science-fiction beam weapon with characteristics that have never been seen before on any scale, all the things in it are things that I know happen in the real world.
Smoke and drywall and concrete dust blasting past a steel beam
will stick to it. Bluff bodies
do set up vortices behind them, and because of the viscosity of the air, the dust on the back side or even on the sides
doesn't come off all at once. That's just how it is. If you haven't stirred around in the real world enough to have encountered such things, it's not my problem.
If you have evidence that something different is happening, or a simpler explanation that consists of things that happen in the real world, I'll consider it.