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Re: [PSUBS-MAILIST] concrete submarine - i did it back in 1994 - worked perfectly

Hi Warren,  Where would you build an underwater house?   Are you aware of any legal (read government) obstuctions to doing something like that?

Brian Cox
----- Original Message ----- 
From: "Warren Greenway" <opensourcesub@yahoo.com>
To: <personal_submersibles@psubs.org>
Sent: Monday, September 29, 2003 8:14 AM
Subject: Re: [PSUBS-MAILIST] concrete submarine - i did it back in 1994 - worked perfectly


> I am curious about viewports and hatches in your hull.
> I want to build an underwater "habit" (read house).
> And
> have looked into quite a few materials. The problem
> with
> concrete has been related to view-ports promarilly. I
> haven't been able to find any information on that. If
> you have any further information of this, or other
> construction methods, you certainly have my attention.
> 
> Warren.
> 
> --- diagroto@ibague.cetcol.net.co wrote:
> > Hello,
> > 
> > I am Wilfried Ellmer and i recently did a search
> > engine search on my name and 
> > found it connected to a discussion on this board
> > about concrete submarine 
> > hulls.
> > This explains why i answer now to a discussion that
> > took place here some 3 
> > years ago.
> > 
> > One of the questions asked was "did everyone a hull
> > or sub like this" .
> > 
> > Yes i did one (in 1994) it was: 9 m long 2.5 meter
> > diameter 18cm wall 
> > thickness, form of a blimp 15 tons wihtout ballast
> > 20tons with ballast.
> > 
> > I also did earlier a smaller hull of 2m long and 0.7
> > m diameter to test the 
> > concept.
> > 
> > Both hulls where converted in fully functioal subs
> > and i personally had a lot 
> > of dives and fun in those two subs.
> > 
> > Fact that i am still writing proves the validity of
> > concept.
> > 
> > Unfortunatly the concept was so new back in 1994
> > that i could not find anyone 
> > interested to discuss or make a projekt with me.
> > 
> > So let me answer from practikal point of view some
> > questions that came up here:
> > 
> > Can you transport a hull like this?
> > 
> > Yes i transported the 9m hull on a truck from
> > innsbruck where i built it to 
> > lake Atter where i dived with it (some 5 hours) did
> > not break, not leak, no 
> > damage.
> > it was stapled on wood - no special transport thing
> > - impacts that occur on a 
> > truck will not affect a hull like this.
> > 
> > Will it crack when you hammer on it ?
> > 
> > This hull had a 18 cm thick concrete walls curved in
> > 3 dimensions - and 
> > reinforced by 5mm steel bar net all 5 cm - this is
> > similar to a bunker wall, 
> > or to a bridge - if you hammer it will it break ? -
> > of course not.
> > 
> > Will it stand hydrostatic pressure ?
> > 
> > Just think of hoover dam, or submarine tunnels, or
> > oil drilling platforms, - 
> > is concrete standing hydrostatic pressure ? - of
> > course for many decades 
> > without any notable change.
> > 
> > Do you need non steel reinforcement?
> > 
> > - no in a 5cm or more thickness concret wall steel
> > bars are perfectly 
> > protected.
> > 
> > Will it stand changing load from waves ?
> > Is concret standing changing load on bridges - of
> > course ! - and in by far 
> > more sever conditions. Or in buildings under erver
> > changing wind pressure.
> > 
> > Is building the hull a tecnical problem ?
> > 
> > handling a 18cm thick ship hull is always a problem
> > - just imagine welding 
> > steel plates of 18cm !!! - or forming them as a
> > sphere or streamlined blimp.
> > (with 3 dimensional curves). I could do it in a
> > backyard with concrete, 
> > (without having bubbles and having reinforcement
> > where it belongs) - i doubt 
> > that i could weld or form 18cm steel plates or alu
> > in a backyard.
> > This is a task that is only (if ever) handled in
> > battleship construction.
> > What you can do with concrete is incredible strong
> > thick walls on relative 
> > small subs - this has nothing to do with ferrocemnt
> > as used in yachting (iron 
> > mashing and plastering on) - this is forming
> > concrete in the way as it is used 
> > in tunnels or in radio towers with continous forming
> > that makes a little part 
> > every day.
> > Had patented some of this stuff... 
> > 
> > Do you need a special covering - double hull etc:
> > 
> > No - just use what is proved in tunnel or dam
> > building it will work excellent 
> > in hydrostatic pressure for decades as it does in
> > dams and tunnels.
> > 
> > Do it only work for big subs ?
> > No - had done 2m sub with 5cm wall thickness and 9m
> > sub with 18cm wall 
> > thickness both worked excellent.
> > 
> > How can you test concrete ?
> > 
> > How do they test dams or bridges or tunnels - x
> > raying every cm? , by using 
> > paleontolgy equipment? (as a discussion suggests) ?
> > 
> > I had a practical approach deep test at 150m (was
> > deepest site i could find in 
> > the lake) and considered it save therefore to dive
> > with 50m.
> > 
> > If you get obvious material changes over time
> > (rusting of steel reinforcement) 
> > visible (new) cracks etc...yust do pressure test
> > again and keep it 1/3 in 
> > normal use this should be save.
> > (by the way...did not get any rusting, or cracks
> > during 15 years of use) - So 
> > is it done in dams, bridges, pressure vessels,
> > concrete pressure hulls of 
> > nuclear plants etc. - periodic testing with overload
> > - new testing if doubths 
> > about structural integrity come up at visual
> > inspection.
> > 
> > No need to predict destruction depth exactly with
> > complicated 
> > methodes...doesn't work anyhow - not even for navy
> > steel hulls - as example of 
> > treasure accident shows.
> > 
> > A wall thickness of 18cm on a 9m boat gives you a
> > calculated destruction depth 
> > far below 1000m (normal concrete without any
> > special) you can keep it so far 
> > above that in normal dive operations that it will be
> > save - no matter - if 
> > anything like bubbles or cracks gives you a little
> > additional weakness.
> > All concrete on all dams, tunnels buildings, drill
> > islands etc. have bubbles 
> > and cracks - do they collaps ? - of course not!
> > 
> > What is the real problem of constructing a sub or
> > habitat with concrete ?
> > 
> > Shipyards are not familiar with this material, and
> > those who are familiar with 
> > it (tunnel engineers) do not build ships or subs.
> > 
> > Are there unsolved problems?
> > 
> > All problems are solved for decades all is available
> > but nobody applies it on 
> > subs.
> > I did it - it worked excellent - had a lot of fun - 
> > 
> > 
> > 
> > If anyone wants to discuss or suggest me a
> > project...please go on.
> > 
> > Wilfried Ellmer
> > 
> > 
> > 
> > 
> > 
> > 
> > 
> > 
> > 
> > 
> 
> 
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