Speaking of which, NIST commissioned an experiment where it had a full-scale section of the floor structure built (4 inch slab held up by fairly light truss "joists", with identical attachment methods to the vertical supports as used in the WTC). They had some difficulty replicating the exact same steel and concrete, and at least in the steel, had to substitute another type of steel that had as similar heat response/structural characteristics of the original, because the original steel simply wasn't manufactured/available any more.But probably more to the point why is full scale physical replication the ONLY method of confirmation you acknowledge?
It was put in the largest bake-test facility they could find, which turned out to be in Toronto Canada at the time. If I recall correctly, the test article was about 100' long and 30'+ wide.
With this they were able to demonstrate the test structure collapsing based on the temperature levels known to exist in the WTC. It matched.
Which ultimately proves that the floors would collapse in the conditions that were known to exist (even as promoted by AE911truth). Once one or more floors collapse, then some sort of ROOSD/progressive failure was inevitable. Pancake? Well, yes, but it got pretty pulverized falling that far. There's photographic evidence of pancake at the very bottom of the debris pile.
[The test is documented in one of the appendices of the NIST report.]