Need a book? Engineering books recommendations...

Return to index: [Subject] [Thread] [Date] [Author]

Re: 9-11 Wackos

[Subject Prev][Subject Next][Thread Prev][Thread Next]
My understanding of controlled demolition is that the charges do not go off simultaneously. It's "CONTROLLED" to minimize debris spread. So first explosion to the beginning time of global failure may take a matter of seconds.

Look at the Seattle Kingdome see a bunch of explosion ring around the building, then a few seconds later, it begins to collapse and falls pretty quickly one that process begins.

Mr. Robertson's design of the World Trade Center saved thousands of lives. Without the luxuries we have today of sophisticated software to model collaspe scenarious I might add.

Yeah other big name engineers (who are in direct competition for the same types of projects) have stated they would have done things different and their designs would have stood up longer or not have collapsed. But that's hindsight isn't it?

IF we can stop people from flying planes into buildings, maybe that would be a good way to approach designing a safe high rise. I dunno, just a thought.

Freefall: mass and ever increasing mass (each floor falling on another) and acceleration (those things were too heavy to reach terminal speed from wind resistance) ...makes perfect sense to me.


On 5/25/07, ECVAl3(--nospam--at) <ECVAl3(--nospam--at)> wrote:
I've seen some of the videos mentioned here and I agree there is a lot of ways to manipulate media to bias public reaction. This is proven everyday in television news broadcasts and newspapers.
The only thing that really haunts me is, with a controlled demolition, the 37 story Sands Hotel in Las Vegas took 17 seconds to completely collapse. With the pancake theory, the 77 story Twin Towers took 9 to 14 seconds to collapse. Does this mean that it is not possible to safely design and engineer tall buildings? What are the limits in height we should be considering in the future to insure the life-health safety issues? Didn't the engineers of the Twin Towers design with due diligence or is this kind of collapse, regardless of the cause, acceptable because of economic or other reasons?
S.Macie, P.E.

See what's free at