23-09-2013, 09:06 PM
Tony Szamboti Wrote:Jeffrey Orling Wrote:All motion begins with acceleration.
Motion of collapse front of WTC reach a constant velocity and did not continue to accelerate.
The examples given are completely different structural systems.
Apples and oranges.
Smoke and Mirrors.
You can fool some of the people some of the time, but not all the people all of the time.
The measurements show the North Tower continued to accelerate and gain velocity.
It is not apples and oranges to compare the Balzac-Vitry building to the North Tower in the sense that if a solid item hits another solid item in an impact, and causes it to accelerate, the impacting object has to decelerate (slow down). Isaac Newton showed us this a while back. In reality, the North Tower should have decelerated even more before any natural failure would occur because it was a stronger structure.
What do you think happened with WTC 7? Do you think it also reached a constant velocity and did not continue to accelerate?
No the north tower did not continue to accelerate. The collapse from the strike zone down was INSIDE the facade (ROOSD) and it reached and was clocked at a terminal. If you can show otherwise... please do. You DO see a fallen panel way below the collapse front which was dropping close to free fall.. so the collapse clearly was not at that speed or rate of acceleration and so there WAS resistance... the floors which had to be shattered by the collapse in rubble flow.
The verinage example is not analogous to the twin tower collapse.
I think what happened to 7WTC was there was a failure of the load transfer structures which were on floors 5-7 and spanned over parts of the sub station. There was a 5 story tall open lobby on the south with no interior columns. The load transfer failure rapidly propagated westward... the column line 79,80 and 81 dropped 8 floors to the ground pulling everything above with them including the east penthouse .. followed by the west penthouse. The transfer structure collapses pulled in the braced frames on the east and west at the perimeter... the north perimeter was supported at the ends of the cantilever girders with no columns below flr 8 with the facade hung from for cantilevers... and when these failures were "done" the curtain wall and perimeter column has not support and plunged 8 floors with the some attached floors pulling in the column line north of the west end of transfer truss 1 causing a vertical kink in the entire north facade... clearly indicated that there was nothing behind it (no floors). The curtain wall accelerated close to... but not evenly at free fall for 104 feet or so... the distance from the ground to the top of floor 7/ bottom of floor 8 structure where the load transfer structures ended (topped out). After the 104 foot decent the curtain wall slowed as it was being crushed in contact with the ground.
Total collapse time from the earliest building movements through the east and west penthouse collapse and the curtain wall collapse was close in the range of 14 seconds or more.