You are groping here and it is showing badly. Weld failure would not be brittle and it would not explain how an asymmetric failure of the interior could produce a symmetric failure of the exterior as the NIST WTC 7 report claims. Their own model even belies their claim as it deforms radically during the interior collapse before the entire exterior comes down.
It seems the world is crashing in on those here who have been insisting the collapse of WTC 7 occurred due to natural circumstances. The reality is that it was a controlled demolition and all the fancy hand waving and spin artistry, of those who want to believe otherwise, won't change that simple reality.
No Tony, I proved it experimentally, and there is a known equation for it, your aguring known
Science, if you can prove me wrong you have your case for CD, but you have to show engineering work not hand waving proclamations to do it.
From Dr. David Benson, page 17,
http://www.physforum.com/index.php?showtopic=12383&st=240
"reasonwhy --- Since this column swings like a inverted pendulum, there is the vertical component and a horizontal component to displacements and velocities. Hence there are horizontal forces, which the engineers like to call lateral loads. Got it now? huh.gif
Everybody --- turns out that 100,000 lbf is not much, once the potent force of gravity is taken into account. Assuming a drop of 12 feet, accelerated at 32 ft/s^2, a mere 2600 lb with a 0.1 foot displacement suffices to produce the required 100,000 lbf, close enough.
Fine! smile.gif Eccentric sudden loads then appear to suffice to destroy column splices. Indeed, I could do the same again each 12 feet for the moment connections in the core floors. Since the length L only appears linearly in the equations, only 3 times as much mass is required.
Now, reasonwhy, just what were you saying about heavy beams? So once started, the collapse progresses easily in the core, smashing through everything by its own mass under the potent force of gravity..."
Show my theory of weld and connection failure is wrong, though actual engineering work and prove the buildings did not fall from natural connection failure.
That is all you have to do Tony Greening and Benson used my theory that I discovered by accident.
Prove me wrong win your case for a new investigation.