We thought about it (filling with water would be even more effective).
However, these options are not viable.
In the end, the exterior forms with ties to the steel shell appear to
do the trick.
Is it possible to pressurize it? Even 1
psi is 144 psf. Even a small pressure could resist the concrete
pressure. Just a thought.
H. Daryl Richardson
Original Message -----
Wednesday, October 27, 2010 7:43 PM
Re: shell stability
My problem is a
large steel tank being used as a form for its own outer concrete shell
with welded ties keeping the shell from buckling during the pour.
Timoshenko's "Theory of Elastic Stability" was my knee-jerk-reaction reference. I also looked into
Roark (which actually cites Timoshenko's formulas for arches, not
shells), as well as Vol'mir's "Flexible Plates and Shells", "Guide to
Stability Design" (Galambos), and several designer's handbooks.
Unfortunately, none of these sources provided a clear-cut solution for
a problem at hand. For example, the Timoshenko's formulas (referenced
in Roark) do not appear quite applicable to shallow arches (my case),
while other formulas that are applicable to such arches lead to quite
paradoxical and seemingly theoretical results.
I ended up modeling the shell in 3D FEA, evaluating stresses, analyzing
the deflected shapes, and still applying the Timoshenko's arch
formulas. The results appear reasonable and corresponding to the field
Alexander Bausk wrote:
Roark's Fomulas for Stress and Strain has and
appropriate entry under paragraph 13.5, "Thin Shells of Revolution
under External Pressure", as well as Table 13.1.
It also has a calculated example thereto all right.
On 27 October 2010 23:50, Steve Gordin <sgordin(--nospam--at)sgeconsulting.com>
> Good afternoon,
> I am looking for a source of Practical analysis of a
> Shallow - Thin - Cylindrical Shell/panel
> Uniform Radial Compression.
> The books I have on the subject turn to be of mostly academic
> Can anyone point me in a right direction?
> Steve Gordin SE
Civil/Structural design & inspection engineer, CAD professional
MSc Structural engineering, Ph.C. Engineering
ONILAES Lab at PSACEA
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