You do have proof, what the heat was and how long the fires took place?
Unnecessary for our purposes. We know there were huge, devestating fires. We know that fire heats things up, we know that heated steel loses strength. We know that steel that loses strength is prone to experiencing creep, distortions, sagging etc. We know from direct experience that the steel in the fire floors experienced creep, distortions, sagging. It is abundantly clear that explaining that creep, distortions, sagging with the heat of fires is totally plausible.
You do have proof of the fire protection was damaged/stripped? etc etc.
Unnecessary for our purposes. It suffices to know that the fire protection was brittle and prone to fall of even under low forces; we know that very large planes hit the columns with very high velocities. We know that these impacts must have excerted extreme forces on everything that the plane debris touched. We know that these forces exceed the low forces needed to strip the fire protection by many many orders of magnitude. Assuming that lots of the fireprotection was ripped off is immensely plausible. Assuming all the fire protection survived these forces is ridiculously implausible.
You do have proof that the heat makes steel lose strength and warp and will get a collapse in 12 seconds thanks to that?
Strawman Logical Fallacy.
The warping behaviour of the steel is not responsible for the collapse duration, and nobody claims that. Heat is the reason why collapses begann, gravity and the
cold properties of the steel below the fire zone are the reason why they progressed at the speed they did.
You do have proof, its only fire and not explosives?
Yes. Any theory that uses explosives to explain collapse initiation or progress must make a few falsifiable predictions:
- Explosions would be heard that are consistent in loudness, timing and brisance with explosive charges able to cut steel
- Flashes would be seen through the windows
- Steel member would have been found that show damages typical for explosive severing (i.e. failure mode was not bending, shear or the like)
- Sniffing dogs who worked the rubble pile would have barked
Etc. No such explosions were heard, no such flashes seen, no such steelk member found, no such dogs noticed anything.
The "explosives" theories, whatever they are, are thus falsified.
For NIST it was 6 years a mistery
Not a mystery. Just something that was not yet sufficiently supported by evidence. NIST does not jump to uninformed conclusions like your 400/1500/2000 do, or like you di yourself.
And NIST still cant explain the total collapse.
And they explain why: Because not enough data is available; too many variables, and too few equations to solve.
Do i have to take examples, where you see the behaviour of steel structures, with even longer bigger fires.
No need to. We have seen them all. These were of fires that were fought, or of structures that did not have the peculiar weaknesses of WTC7, or that did not experience plane crashes, or did indeed experience progressive collapse of their steel frame parts.
Or you going to show me an example of the same steel structure who behaves like the wtc towers?
Unnecessary. One-time events are not impossible just because you don't have a second example. If that were so, I suppose I am immortal, for I have never before in history died, and there is no example of Oystein dying. Yet I somehow think that I will in fact die one day, and when I do, it will not be a total mystery.