At 08:42 am 16/12/2005 -0600, Richard wrote:
> Frank...
> I have spent some thoughtful time in thinking
> of "your magnificent obsession" dealing with B*a
> and the internal pressure of concrete. Sad that
> the Glen Canyon cavitation incident was left to
> explain itself.
The interesting thing about Glen Canyon is that the
engineers didn't bother with the physics. They just
thought up an ingenious way to fix the problem
=========================================================
Contractors blast away damaged concrete, fix tunnel
linings and fill holes with 3,000 cubic yards of concrete.
Engineers, meanwhile, begin their own race to retrofit
the dam with aeration slots, a new technology that
introduces small amounts of air into rushing water,
cushioning the blow of imploding vapor cavities.
The plan works. The '84 runoff sets more records,
but the spillways show no sign of cavitation.
This success leads the Bureau of Reclamation to
retrofit aerators to two other large dams, Hoover
and Blue Mesa. "It was a defining moment in dam
design," says Burgi. "The world was watching how
we were going to solve this problem." As it turns
out, the world did more than watch -- aeration
slots are now standard from the Tarbela Dam in
Pakistan to the Infiernillo Dam in Mexico.
=========================================================
In effect, they fed the Beta-atmosphere with
Alpha-atmosphere cracks thereby virtually
annihilating the water's tensile strength.
It is difficult for engineers to appreciate that
it is not the external stress on a material that
leads to failure but the difference between the
external and the internal stress.
It is even more difficult for physicists and
chemists to understand that....
-----------------------------------------------
..... as our work on concrete showed
the important thing isn't the external pressure
but the difference in pressure between the
inside and the outside.
One can achieve this difference,
either by increasing the external pressure,
the numerator pressure, with an atomic
fission bomb (hot fusion),
or by decreasing the internal pressure, the
denominator pressure, by 3D Casimir Plate
expansion - (cold fusion)
-----------------------------------------------
...but they will - eventually - when they
realise they have things inside out. 8-)
Frank
