26-08-2013, 11:54 AM
Jeffrey Orling Wrote:Phil Dragoo Wrote:Tony at 555
Lacking is any initiator of the observed multifloor failure and drop.
The drop and movement were the result of multiple forces and factors... beginning with the mechanical destruction of the columns by the plane impact, the fires which started from the air line fuel, and electrical shorts, office contents inlcuding plastic and other combustible substances, failure of the fire protection. Connections were the weak links in the steel frame and failed before any steel they connected would.
No one knows the precise sequence of failures and how the frames loads were redistributed and eventually overwhelmed what was left of the structure (axial load paths). When axial load strength dropped below service loads the top section descended and the facade dropped, twisted, translated and the connections broke and some sections still connected cuckled... as in the last remaining connected columns.
This is what the observations indicate. Ignore at your own peril.
Mister Jeffrey, this is not a scientific explanation. Can you please provide the following
- where the evidence is for the necessary 650 deg. C (1,202 deg. F) steel temperatures to cause the core column axial load strength to fall under their service load.
- where the lateral load necessary to translate the 12 story upper section and cause the columns to miss each other, the way you claim, would have come from.
so we can see how you came to your conclusions. Again, they don't need to be your own and can even be estimates of some sort. Isn't it important to you that you are seen as being a rational person who would base their thinking on science?