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- To: "Struct EngAssoc" <seaint(--nospam--at)seaint.org>
- Subject: FREE FALL
- From: "ASC" <ggg(--nospam--at)bigpond.net.au>
- Date: Tue, 25 Apr 2006 18:41:50 +1000
YOU ARE RIGHT IN THAT WHEN THE FALL IS OBSTRUCTED
the duration should be longer than in a free fall.
But consider that we are talking about the duration of what's visible on
the outside. There is a belief that the fall was started inside, by the core
collapsing. This was well in progress before the destruction was visible on the outside.
In this sense the core was pulling the outside down,
acting via a very flexible connection.
This is my belief, anyway.
From: David Merrick <MRKGP(--nospam--at)winfirst.com>
To: SEAINT <seaint(--nospam--at)seaint.org>
Subject: 9-11 free-fall
Has anyone predicted and measured the fall time of the 9-11 twin towers?
I have listened to a summary of an analysis that concluded that the
world trade towers, fell (9/11/01) at the speed of a free falling
object. They state that at free-fall speed, the complete decent should
conclude in less than 10 seconds. Varying reports timed the fall,
ranging from 8.2 to 9.4 seconds.
The lower floors would have had to crush under the falling floors above.
This resistance should have slowed the fall. The claim is that the
energy absorption would have increased the fall time 3 to 4 times. It
was concluded that the simplest solution is that the columns were
destroyed, manually as the building fell, like in a controlled demolition.
An asymmetrical airplane crash did result in a perfect vertical fall.
Dr Gregory Szuladzinski, FIEAust
Analytical Service Pty Ltd
5 Warwick St
Killara 2071, Australia
Tel. 612 9418-1842
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