Re: concrete weight

[shawl@torchlake.com (Jonathan Shawl)]

I think I found what I was looking for.

Dave Irons said;
>"That would depend on the diameter of the hull
>A slightly buoyant submersible would could have a hull thickness of . 08 the
>outside diameter of the hull.  Example.  A five foot diameter hull = 4.8 inch
>hull thickness.  A two meter diameter hull = 16 cm.  Most of the pressure
>hulls studied were slightly buoyant.  Most were thinner than . 08 so the numbers
are
>a little conservative."

"slightly buoyant" Is good news for a underwater habitat because it won't take much
to hold it under water.
But I think a sub hull needs to be more than "slightly buoyant" or you will have to
add some other form of  non compressible buoyant material to help carry the payload
weight. This is the case with Alvin and some other "overweight" deep diving subs
that use a non compressible foam to add to their buoyancy. I think it is glass
micro bubbles in a resin. I'll bet that stuff is not cheep. Any body know about or
use this foam?

Jon Shawl