Submarine Yacht project

that's an excellent approach wil, and a good overview of how we approach design in general.

its certainly how i developed the math model for the earlier model we discussed, which was an unreinforced thin-wall concrete vessel. buckling was a service condition that could be managed. there were other issues however for the thin-wall model, issues that you seem to be avoiding from what i can see in the photos.

in my math model i inverted the forces on an unreinforced concrete tank to simulate water pressure on sections of the submarine. sea water density and 6ksi x 1/4" concrete. sea water density. a static condition compliments the shape, but then i applied load conditions to simulate what i imagined might be service cases. granted, i was sitting in a public hearing late at night most of the time that i was doing this on my laptop. nonetheless a tubular shape, such as the leg of an oil rig or the like, is generally complimented by the inversion of forces and buckling is only a problem when the forces exceed the compressive strength of the concrete, which as you point out is a shell thickness game.

what i observed, which is not in the math of it all per se, is the quality assurance and control during forming of the work would be extraordinarily high. beyond normal, and i was concerned with the heat of hydration the during curing process. these are all manageable

i repeatedly crashed my software with the conical nose and eventually broke that down into a finite analysis of panels, which necessarily require steel.

the special load conditions that did not work without steel, and a lot of it, were in the tower, controls, shaft / tail section, and keels / ribs. what i found was that service loads for dry-dock in particular were exacting. for example, cribbing or chalks would need to replicate the geometry of the shell with exacting precision and steel is necessary to carry point loads. it would take very little error in the unreinforced model for catastrophic failure, and with reinforced concrete sufficient rigidity in the structure to prevent cracking.

service loads for dock / mooring produces the same point loads, and i used a single case of windage to model these loads. again, steel is needed.

what i didn't get into was vibration, which by instinct is my single largest concern. from a practical perspective. my guess is that a physical, operational concrete submarine can be produced. diving bells and more static service cases could also be produced i would imagine. but the long term effects of vibration, either internally generated or produced through say cavitation, would have a deleterious effect in ways that i would again imagine are more associated with operating / maintenance costs. seems the vessel would have limits on its operating capabilities and service conditions.

best i can offer wil and again much success. its an ambitious plan indeed.

 

What are you useing/going to use for ports and through hulls?

K9

 

Nice to see some progress!

I noticed though that the hull is quite a bit more irregular than the one of your prototype. Did you run in production problems due to the bigger scale?
And how do you plan to move the hull into the water (as I can not see any preparations for that)?

Oh and what type of black paint have you applied and for which reason?

One final question: What is the internal volume of that hull?

 

New Concrete Design Proposal!!!

Hello Wil,
I am and have been a certified scubadiver for well over twenty years now,am also pretty familiar with, but no expert in math and nautical design,pressure at depth,bouyancy and even some 'home slab' reinforced concrete construction,etc....But I am also a dreamer/amatuer designer/model-builder of science and future technologies when I am not working at my full time job...
And I see future possibilities for countless concrete undersea habitats,submersable transportation to and from different areas and habitats built around the world.
An interesting future thinking book along these lines is the 'Millennial Project' by Marshall T. Savage....
I have been enjoyably looking over your website and reading many of the threads here on your concrete submarine and your and others testimonials and comments made and I am finding the possibilities and ideas of a submersible,ocean voyaging,habitation,long range yacht, a very interesting,thought provoking,design concept and obviously proven possible by you for ten years now in your own research/prototype and in production phases you are progressing in already...
I am new here tonight, to this forum and I am just interjecting some questions, thoughts,ideas,possiblities, and possible design plans and idea that I am doing on my own and researching on my own.
Some questions for thought I have are as follows for my own prototype design idea are:
#1 Shallow diving and working depths ie. from surface to 60 feet maximum with necessary safety factors included in the design, to at least double the working/cruising depth or a bit more? Not meant to be fast or a deep diving design!!!
The majority of vivid colors and interesting sea life live less than 100 feet under the surface and in and near the coral reefs and shoal areas...
#2 One uniform/complete cast hull construction of steel reinforced concrete approximately 4 inches plus in wall thickness with necessary form and function bulkhead walls to designate any necessary support to structure/ living/working/engine areas.
More in the design/shape ideas and thoughts of a 'Jellyfish' shape,ie. dome like on top,entry/exit hatch on top and more substantially flat surfaced on the bottom with additional space underside,designed,cast and hydrodynamic,streamline molded on underside for additional ballast,diesal fuel and large enough in design for appropiate size air chambers for ascent and decent control?
#3 Allowances for larger acrylic viewing windows or ports especially on bow position in consideration of maximum shallower depths of operation and normal cruise depths of under 5 atmospheres pressure at depth,ie. under 100 psi pressure on hull and window ports?
* Safe Diving and Design Limits Not to exceed dives of 150-200 feet maximum
#4 Dimensions possibly 30 feet in diameter and a height of possibly 8 feet plus?
Not only a form of long-range transportation but large enough to also be a mobile habitat in the sea for 2 to 4 occupants...
*Obviously which would require building site(s) near coastal zones or areas
#5 Approximately 700 + square feet of living and working space for 2 -4(possibly parents and two young children)occupants and small engine room/shop and with enough added dome height for possibly a second level main command/navigation/charting/driving and control area?
#6 Lower first level would be allotted for living working,sleeping and undersea viewing/entertainment in forward bow area?
#7 Control surfaces would be similar in nature and design to airplane rudder and elevator type at stern?
I am working currently on simple basic drawings and building a 1 inch to 1 foot scale model of this to have my drawings and model photographs notarized and copywritten to date.
I would enjoy your and anyone else in the forums feedback as to the possibilities of a shallow-diving,long- range cruising yacht/habitat of this design being a feasable project?
Best Regards,Dan

 

Hello Dan,

In fact i am exploring some of the possibilities you are mentioning here with serious investors - so i am sure we will do interesting things here...

What concerns depth - the general mark for floating and other submerged concrete pressure structures is about 300m. Extensive research has been done for 1500m.

Marine ambients create about 1mio load cycles/year (wave action) and concrete structures are considered safe under such conditions up to 100 years of service life.

So this opens a wide field of private submarines, floating habitats, sea steading, stream turbine applications and much more...



here are some new pictures of my current project. A private submarine yacht 200 tons for a california customer.

Cheers,
Wil
http://concretesubmarine.com

 

I realize this is a boat design forum but since you guys are discussing concrete subs I wanted to throw an idea out there.

What is the possibility of building a concrete diving suit. Something with articulated arms maybe but an essentially enclosed main body. I envision it looking like the WASP Atmospheric Diving suit (http://www.oceaneering.com/uploadedImages/Subsea_Projects/Diving/Pages/wasp_02.jpg).

Would still need the oil filled rotary joints but the rest of it is doable with the same design ideas. The suit would be thick and heavy but so are standard ADS diving suits and I would think a concrete one would be orders of magnitude cheaper.

Ideas?

 

dear oh dear oh dear dear oh dear dear oh dear dear oh dear dear oh dear
dear oh dear dear oh dear ....

is there no end of crazy cut price nuts out there ?????????

$30,000 is bloody cheap to guarantee of your safety when you are 150 ft down and have all that water on top of you.

Mind you , $200 of concrete and oil filled joints is a really cheap coffin ... go for it

 

composites.

 

????

harlemriverman,

composites?

 

comment to gideon, a concrete dive suit is an impractical turn in the road.

 

hi wil!

amacing project and i am very intrigued by your submarines.

has the idea of building a sub with 2 tubes ever crossed your mind?
i mean - 2 of your blimbs set up parallel and merged together at their thickest part over a reasonable lenght.
getting more living space without widening the blimbs and therfore also with no need for thicker concrete since the pressure the blimbs have to withstand is still the same.
the intersection needs to be supported efficently as well though.
the parts between the 2 hulls could be covered and formed hydrodynamicaly with rather cheap and thin material (glassfibre composit) provided the space covered by this "panels" gets submerged.

this would give you the oportunity to:
- place ballast "outside" the hulls and hence not breaching safety by installing extra portholes in order to release the ballast
- emergency bouyoncy equipmet could also very easyly be placed there (lifting ballons or such)
- you get 2 propellers thus increasing manoverability and with an diesel electric propulsion system there is still only need for 1 generator (big enough of course)
- if 1 hull brakes, you get a safe haven in the second provided the hatches in between are watertight and in combination with the afore mentionend emergeny bouancy devices the sub might even still float
- you will have a sort of platform for recreational use when at anchor, which could also be placed in the intersection

- construction will be a lot more complicated though......
regards

btw - the CO2 issue was mentioned in an old post....
did you know that it takes up to 10, 20 years for concrete to completly cure out?
all along this time CO2 is sucked up by the concrete and transformed by the chemical reaction therein to chalk.... it is not very much but clearly measureable as the failure of biosphere 2 demonstrated
http://de.wikipedia.org/wiki/Biosphäre_2

 

Just make submarine oval like russian subs, not as strong as but still pretty strong and much wider beam.

 

Sounds like a good idea. Several pressurized aircraft were built with figure 8 hull sections. For an aircraft, the web joining the sides at the center where the section narrows is under tension. For a sub the web is under compression so it can be made of concrete like the rest. Works with the tubes side-by-side or one above the other.

 

i haven't done any calculations on it, but it might not be the case....
the resulting force from the outside pressure works against the joints and thus creating a momentum, trying to flip the parts outwards .. my english is bad and i would like to find better words ...

nonetheless - the waterpressure at this section is working against this momentum and idealy equalizing it.
thourogh calculations have to be done in any case to determine wether the momentum or the waterpressure wins and the intersection needs to be designed accordingly - concrete pillars in case its under pressure, steel in case the momentum creates tension in this parts.

the good thing though is, that no matter how deep the sub desencds the forces are always coming the same way (pressure or tension) just increasing by depth.

 

I was basing my statement on a simple reversal of the figure-8 aircraft fuselage case, which can be demonstrated easily by squeezing a long balloon between 2 sticks. The Saunders Roe Princess flying boat was one of the earliest aircraft to have this fuselage profile.

In the submarine case, each segment considered alone has its skin under compression as a result of external pressure. When the 2 segments are joined together the vectors representing the tension in the skins resolves into a single inward force vector at the joint which must be balanced by compression in the web or partition between the segments.

Looking at the forces acting on the skin of one segment at the joint, the pressure inwards plus the skin compression plus the web compression form a trinagle of forces which cancel out (gravity ignored).