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Re: Are there physics lessons to be learned from Texas A&M traged y.



Richard,

Thanks for the link to the Houston Chronicle coverage. They have an
excellent photograph of an earlier bonfire collapse that shows the fatal
flaws in the design. Namely, that the stack depends for its stability on a
uniform distribution of mass around the center pole, which must absorb all
the lateral forces; and that the rough logs that are wired together to form
the stack can shift easily if there is an asymmetric distribution of lateral
forces causing collapse.

In my opinion, if no design changes were made after the earlier
collapse, there was negligence involved.

Following the Thanksgiving vacation I'll be covering equilibrium in
my introductory physics class. I'm going to use this case as an example of
unstable equilibrium!

Mark

-----Original Message-----
From: Richard Grandy [mailto:rgrandy@RUF.RICE.EDU]
Sent: Saturday, November 20, 1999 5:13 PM
To: PHYS-L@lists.nau.edu
Subject: Re: Are there physics lessons to be learned from Texas A&M
tragedy.


I'm from Rice, not A&M, but I believe the motive was to get as tall a
bonfire as possible with the material available.

The method seems to have been to bury a tall pole partly in the ground and
then to stand the logs on end and wire them to the central pole, then wire
others to those,and so on.

According to reports in the Houston Chronicle members of the engineering
department had warned their chair that this was an unstable configuration
several years ago, but it was never reported further up. A&M is a former
military school which is still highly authoritarian and one suspects that
raising mere theoretical engineering questions about a central tradition
would not have been welcomed.

The current story is at: http://www.chron.com/

Richard Grandy
Rice University
Houston TX