25-08-2013, 02:39 PM
(This post was last modified: 25-08-2013, 04:35 PM by Tony Szamboti.)
Jeffrey Orling Wrote:When core aggregate axial load capacity had dropped below service loads the movements show that the columns were translated laterally enough so that and there would therefore be no column resistence or impacts. Didn't happen... strawman argument. There was likely a few remaining columns which saw enormous loads and rapidly buckled like a pretzel and accounted for the virtual hinge rotation and translation.
What you are saying here is just as impossible as your notion of the hat truss transferring the core loads to the perimeter, and it is not a surprise that you provide no scientific basis for it.
To get the core to drop naturally the columns would have needed to be heated to 650 degrees C (1,202 degrees F) nearly simultaneously. Where is the evidence for that kind of heating, without even considering the simultaneous nature of it needed?
Even if heating could have gotten as hot as needed the constant vertical acceleration observed through the first story can be shown to be impossible due to heating induced buckling. If you think that heating caused it you should be able to show how it could accelerate as fast as it did via an energy calculation for the remaining column resistance during buckling. So how do you account for the 5.1 m/s^2 vertical acceleration through the first story?
Lateral translation requires a lateral load, and lateral movement of large things, like the upper 12 stories of the North Tower, would require a very large lateral load. From where I sit the only significant load acting on the upper section is due to gravity and that is a vertical load. Where does your lateral load to shift the upper section columns out of alignment with those of the lower section come from?
Come on Jeffrey, provide a scientific basis for what you are saying here. Let us see how you came to these conclusions.