Quote Originally Posted by MrDark71
My only other issue is Chris' claims of what is needed to replicate the towers destruction .....I'd like to know where your pyrotechnical ordinance knowledge comes from?
In 1984 I worked for about 4 months as a driller on a project under a licensed blaster and gained a great deal of understanding of how explosives did the damage they do. Following that I read the blasters handbook and another text dealing with the spectrum of materials in use. Over the years I've encountered a number of ex military people who have had considerable experience in demolition with high density high explosives, of course I picked their brains.

As a driller I learned how critical it was to get the explosives perfectly centered. Distribution was something that became obvious through study as the blasting I was doing only did one shot at a time except for the pre shear of the cut slope. After the shearing of the cut slope the mass was taken out one shot at a time with a technique called "cushion blasting" utilizing ANFO in 10 foot vertical benches.

If the explosives are not centered, complete breakage does not occur. What happens is a hole is blown out the side and the rock formation or concrete in the case of the towers is left mostly whole. In the case of the towers, the reduction to sand and gravel is not short of phenomenal. When I was blasting I felt lucky to get 30% breakage down to particulate. At the WTC there was 100% breakage where detonation occurred per plan.

http://www.w3.org/People/Jacobs/2001...c/pdrm1943.jpg

I have thought that perhaps cameras were confiscated at GZ because there was an intention to prevent recording hydraulic breakers busting up the few large pieces of concrete that were left lying around.