I would not see the structures above (seastar restaurant and jordan observatory) as a spar design also they look similar - in a typical spar the underwater part is not used for living - just to stabilize the platform. This means you have a lot of expensive structure to create a very small living space (suspended above the waves) so you get a incredibly bad cost per squaremeter what is not a big problem for oil industry but it IS for seasteading.

I would call those structures above a submerged living space bubble with a relative thick snorkel that can contain a stairway for easy access to the submerged living space. Sea orbiter is a similar concept. The argument against submerged living space bubbles (i avoid the misleading word submarine) was "complicated to build" needs complicated machinery for buoyancy and depth control. It is obvious that those structures do not contain ANY machinery nor depth control mechanism they are "hanging on the snorkel"  to keep depth - they are not complicated and not expensive to build they are able to survive ANY wave the ocean may bring up they are scaleable (a small one of a few meter diameter can host a family - a stadion size one can host a village) they can be connected among each other - they are not prone to violent horizontal movements, they do not need a lot of fuel for station keeping, they are not influenced by wind, they do not track waves...etc...

All in all a LOT of good reasons to build a seastead in a similar (in part submerged) way.

At the end seasteading burns down to a very basic engineering and real estate question - what is the most economic way to build a save living space bubble in the high seas ? can we compete with land based living space in the end?

Possible there are multiple answers .... and answers we have not considered yet...

We should start to investigate all concepts that bring living space to the high seas and compare their real estate prices in cost per cubic meter. I am sure there will be no elevated platform concept among the winners.

Maybe we should take the 3 best concepts and do some practical development from there.

I am sure that concrete flat rafts and (part) submerged concrete shells are two of the winning concepts.

Breaking it down further there are several axes along which seasteading will probably develop:

The catamaran float / The plate float out / The real estate squaremeter deal / The Captain Nemo float out / The bubble hotel / The current turbine / Breakwater lagoon marina / Oceanic port city design /

Wil

concretesubmarine.com

European Submarine Structures AB

-- Edited by admin on Monday 12th of December 2011 12:35:24 PM

When talking about protection from wave damage we should have clear that one thing is being protected from wave hazard and sea sickening movements what happens inmediatly when you are submerged - and the other thing is how deep in the ocean you might notice the pass of big waves.

Wave hazards come from 2 factors:

1) breaking crests that can hit a structure with hundreds of tons of force

2) Hog and Sag, bending and torsion, forces which appear when a ship is supported by water (and bouyancy) at one end and in the air at the other end. Those forces can break a ship or lead to fatigue. They make a ship stamp and roll.

If you leave the math and wave amplitude thing apart, you can easyly understand that neither wave crests nor hog and sag can exist anymore as soon as you have a thin water layer closing above you, even when this layer is just a foot deep. The structure will be supported uniformly by water at its whole length and this uniform support leads inmediatly to a much calmer behavior.

This is what a diver experiences when he jumps from a rocking surface boat  - there is inmediatly this incredible calm uniformly supported floating status when you go below the surface it dos not  start gradually dozends of meters down - it is just below the surface. No wave is HITTING you anymore no wave is pushing you and your equpment around as it is the case when you swim on the surface. The only thing you experience below is a kind of current that changes direction with every wave. So you can "percieve the wave movement" when you have a visual reference to the sea bottom. If you don`t have this visual reference you will not notice the movement.

I know a lot of divers that are suceptible to seasickness in a rolling diveboat and they are always the first to jump overboard - once you are below seasickness is gone.

I experienced this in extreme form at Malpelo Island which is a island in the pacific 500 km off the coast of Colombia between Cocos and Galapagos - you have those real big pacific waves comming in directly towards a volcanic rock face. There is no doubt that any ship no matter the thickness of its steel plating would be hacked to small pieces within minutes. The divers jump overboard far from the rocks and swimm below the surface directly towards this rockfaces - this is where all those beautiful fishes are. You hang there 1-2m below the "hackzone" relaxed enjoy the smooth waiven of the waves comming in, you can feel the real big suckers in your ears, as the waterdepth changes while the crest goes trough. It is a wonderful place to mediate about the fact why nature never developed a surface swimming animal for the open sea - maybe living below is just so much better.

The other experience i can contribute is the experience i had with the submarine yacht prototype - while i had the sub on its anchorplace and was tooling around inside i closed the hatch to avoid questions from courious visitors - i was there for an hour or so and when i opened the hatch i noticed that a storm had come up, several trees felt down, sailing yachts in the 30 foot range where calling SOS, and the local rescue crew was busy to assist. - I did not even notice the storm. And the hull was still on the surface exposing the sail (tower) and the central rounded part of the hull a bit above the surface. Obviously this did not present enough wave and weather attack surface to make the hull rock and roll.

sub on anchorplace                          inside the sub on anchorplace            diver below breaking waves             structural weakness of a whale body no stifness required as supported by water

-------------------------------------------------------------------

The difference between being hit by the waves on the surface and being supported completly by liquid is paramount - this is why whales have structural weak bodies compared to a ship, they can live with a lot less structure.

Modern shipbuilding is including ballast tanks into the design to deepload the vessel when necessary to avoid excessive bending in the violent surface layer and get a more uniform hull support.

The question how deep is deep enough is most of all a practical question -  i would say a few feet is enough for leaving your coffee cup on the table in 99% of the sea states you will experience, 10m will be enough for leaving the coffee cup on the table in the perfect storm. What means that there is no need to go beyond a depth where a decent snorkel is still possible.

I know that there are people theroizizing that big waves reach deep down in the ocean - the point is theirs hazardous and seasickening action depends on intermittent air/iquid contacts with the hull  - and those are gone inmediatly below the surface. What is left below is waiven that does no harm and no seasickness - any diver can tell you that.

Wil

concretesubmarine.com

European Submarine Structures AB

There are hundreds of giant holow concrete structures like bridge pylons,  underwater tunnels, oilrig legs, working in depths of hundreds of meters maintaining 1 atm interior pressure as we speak already.

Floating concrete structures are good for a maximum depth of 1400m (see study below)

-----------

Paper Number     3011-MS
Title    OCEAN IMPLOSION TEST OF CONCRETE (SEACON) CYLINDRICAL STRUCTURE
Authors    Roy S. Highberg and Harvey H. Haynes, Civil Engineering Laboratory
Source   

Offshore Technology Conference, 2-5 May , Houston, Texas
Copyright    1977. Offshore Technology Conference
Language    English
Preview    ABSTRACT

An ocean implosion test was conducted on a pressure-resistant concrete cylindrical structure to obtain the depth at implosion. The structure was a reinforced concrete cylinder with hemispherical end caps, twenty feet (6.1 m) in overall length, ten feet (3.05 m) in outside diameter, and 9.5 inches (241 mm) in wall thickness. The structure was near-neutrally buoyant having a positive buoyancy of 12,000 pounds (5.4 Mg) for a hull displacement of 85,000 pounds (38.5 Mg). The implosion depth of the cylinder was 4700 feet (1430 m). A predicted implosion depth, using an empirical design equation based upon past test results, was 16 percent less than the actual implosion depth.

INTRODUCTION

A pressure-resistant, reinforced concrete hull was constructed in 1971 as part of a Seafloor Construction Experiment, SEACON I. The structure was placed on the seafloor at a depth of 600 feet (180 m) for 10 months. Figure 1 shows the SEACON I hull prior to its ocean emplacement. Since its retrieval in 1972, it has been located in the open air about 150 ft. (50 m) from the ocean. In the summer of 1976, the structure was returned to the ocean for an ultimate load test, that is, the structure was lowered into the ocean until implosion.

SPECIMEN DESCRIPTION

The cylindrical structure was assembled from three precast, reinforced concrete sections. The straight cylinder section, 10.1 feet (3080 mm) in outside diameter by 10 feet (3050 mm) in length by 9.5 inches (241 mm) in wall thickness, was fabricated by United Concrete Pipe Corporation. The concrete hemisphere end-closures, 10.1 feet (3080 mm) in outside diameter by 9.5 inches (241 mm) in wall thickness, were fabricated in-house. Tolerances on the sections conformed to concrete pipe standards of not to exceed to ±0.75 inch (19 mm) for the inside diameter or minus 0.5 inch (13 mm) for the wall thickness.

Steel reinforcement in the amount of 0.70% by area was used in both the axial and hoop direction. Reinforcing bars of 0.6 inch (15 mm) diameter were employed throughout the structure. A double circular reinforcement cage was fabricated for each precast section; the concrete cover on the outside and inside reinforcing cage was 1 inch (25 mm). For the cylinder section, hoop rebars had a spacing of 27.25 inches (692 nm) and 31.25 inches (794 mm) for the inside and outside cages respectively.

The hemispherical end-closures were bonded to the cylinder section with an epoxy adhesive, no other attachment besides the epoxy bond was employed (Figure 2). The gap between the mating surfaces of the hemisphere and the cylinder was less than 0.13 inch (3 mm) for 75% of the contact area. Prior to epoxy bonding, the concrete surfaces were prepared by sandblasting and washing with acetone.

Source: http://www.onepetro.org/mslib/servlet/onepetropreview?id=OTC-3011-MS&soc...

----------

In other words if you build a bubble that floats deeploaded in cylinder, blimp, donut, sphere, and any other shape that burns down to a non buckling compression arch as basic structural element you can dive it below 1000m .

A seastead bubble hanging out at a few meters on a snorkel should not be a problem not even if the century storm pressure spikes it with 10m.

Wil

concretesubmarine.com

European Submarine Structures AB

Yes, i have seen that a lot too. What happens is that this concrete was poorly executed in first place - you can not see it at the moment of pour - but you see it a few months after. The rebar rusts and increases its volume 4 times in the process, this rips the piece apart. The good thing is there is no "hidden failure mode" the failure is clearly visibe at plain sight.

So when your "concrete" looks good after a few months it IS good and will stay good for 200 years. If it looks bad and spalling after a few months it was no "concrete" in the sense of civil engineering in first place you probably produced something like wet sand with insufficient cement/water ratios crowned by a insufficient curing process.

The worst attack happens not where the piece is in the seawater it happens where the material gets wet and dry out frequently they call it "splash zone". So when you look at concrete in costal zones you are probably looking pertty much at the worst case that can happen (amateurs mixing low quality coastal defenses for the spash zone).

You should have a look at barges built in WW1 and 2 - which are harder and stronger today than they where when built (concrete increases strength over time) and where the steel is so perfectly conserved after 70 years of uninterupted seawater contact that you can still read the original mill stamp.

Wil

concretesubmarine.com

European Submarine Structures AB

 "claustrophobic scenario discussion" is frequently up when talking about submerged living space  - what i really have in mind are concrete shell living space ambients in  bubble look with the feel of the living space shown in those fotos...

I agree that the scycologic factor is the most important argument against submerged structures.

A plate shape stadion seastead with the feel of being on surface and the sky all over you althoug you live technically below the waterline (like in netherlands) migh be a starting point for people that do not like the idea of being submerged.

Those who have absolute no problem with submerged might go for radical new ambients like the submerged restaurant below or the architecture of modern aquariums with their acrylic tunnels.

Wil

concretesubmarine.com

European Submarine Structures AB

   

In the morning you would row over to the beach meet with people from the other boats, have a beach grill, a coconut, a island adventure - you would only return to your boat to have a pleaseant night sleep in a king size bed and a freshwater shower.

There are differences in lifestyle to other yachties. For example when you leave your boat in the morning (all of your family - nobody wants to stay and watch the family home) you just close the hatch - so your living space becomes absolute burglar safe.

The other yachties always live a bit preocupied about their boat, is somebody breaking in to steal your nav equipment?, is the weather on the anchorplace changing smashing the boat against the reef?,  - so they tend to live "in sight" of the boat.

You on the other hand, when get an offer for this dream on week trip - take it - when you return you will find your stuff well protected inside your living space bubble - just exactly as you left it there - breaking in trough a hatch is like breaking into a banksafe - nobody can deploy the necessary (heavy industrial) tools on a anchorplace.

Another situation where your life is really different to a yachtie is when you are together with several sailing and motor yachts anchored in front of this pristine beach of a unhabitated island. Somebody has a radio and spreads the news that tropical cyclon Bertha category 4 is closing in. Now it becomes clear why this beautiful island was uninhabitated in first place - no save harbor miles around.

Some yachts rush out into the dark of the night to make it by the speed of their expensive engines to the next safe spot - just to find that it is cramped with poorly anchored industrial barges that tend to come loose in a storm and grind everything in their way to pieces.

Smaller yachts send the kids for the nearest hotel to be safe and go for the mangroves to bring out several lines to the trunks and fight it out. They can make it as long as the storm surge is moderate.

You on the other hand just close your hatch drink a coffee watch TV - no need to leave the anchor place. If things become bumpy flood your ballast tanks and lay your bubble some 5m down on the sandy lagoon bottom until the storm has passed over you. You and your family are safe as in a underground bunker.

You could take advantage of the **** weather and the sudden absence of all your yachtie friends and make a few miles to visit the next spot. You sail out directly into the storm - trim your living space bubble at snorkel depth - you leave the coffee cup on the table, you watch the weather the sea and ship traffic with your snorkel top camara - but your comfort is not affected by the storm.


Your live will also be a bit different when aproaching a cramped marina with no space for "another boat" - you will always be the "most exotic boat" that draws the attention and marina owners will love to asign you a nice place to stay - maybe for free. While it may be difficult to have privacy in a cramped marina on a surface boat - you close your hatch and you have it.

Your living space bubble will also be different in terms of aircon, comfort electrics, and loading capacity.

For example a yacht in the caribbean can spend dozends of dollars a day in aircon to make the climate below a sun heated deck just bearable. The seawater around your hull maintains the inside at 22 degee with no aircon need.

Yacht owners sometimes go crazy with the vibrations and noise of the small generator that keeps the battery and freezer alive. Noise dampening and vibration is most of all a function of bulkhead weight - bad news for "leight weight yacht outfitting" - you have your generator behind 20cm concrete - complete silence guaranteed.

Yachties are always short of loading capacity for freshwater food, tools, equipment.

You on the other hand have dozends of tons loading capacity this gives you not only the freedom of a much longer range compared with similar sized surface yachts - it also allows you to make a living as a trader - moving cold beer in hotel quantity to remote locations.

Wil

concretesubmarine.com

European Submarine Structures AB

... the pool of photos that are "declassified by our internal censorship process" to show on internet is a bit limited i give you that  - we need to restrict photos for the reasons detailled (here) -  the best summary of official photos is this one - photogallery-

The closest thing to a tour of the 200 ton sub we are currently building for Ian are the video collection at youtube ( video collection submarine habitat )

The sweet spot of speed for (part) submerged economic long distance ocean cruising is in the range of the cruising speed of a whale 5-7 knots studies of whale energetics suggest that a 200 ton whale uses some 50 HP for locomotion and body functions.

So we will be fine with a car sized engine in a sub habitat of 200 tons covering both locomotion and consumer electrics. This is a ridiculous small engine for a 200 ton surface boat (a 600 HP engine would be recommended for a motor sailer) - you would never get the bow into the wind in a storm - for a submerged living space bubble it works just fine.

We will optimize the propeller for 5-7 knots.

Wil

concretesubmarine.com

European Submarine Structures AB

I am not a big fan of sending out a whole population of a city in inflatable floats on the open ocean in a hundred year storm - just remember the past evacuations of cities (New Orleans) and its practical application.  People will always tend to stay in their houses. Also as the example of the fastnet race shows many of those floating out in inflatable rafts drowned although the yacht hull was found later without mast and keel but still floating. So why not think  in a concept where the living space shell IS the rescue float and the safe room.

As you mentioned the dome shell house - make it a "bubble house"  that can float for itself if necessary - even riped apart from a destroyed seastead - It would be like ants, living in a foam block, the living space bubbles would break apart just to stay afloat on their own. 

You would have to make a couple of adaptions to your living space enclosure  - windows like the egg shell - (small to take wave hits but you can have a LOT of them for a well lighed interior), a watertight entrance door.

The dome house is "almost there" and it is NOT a expensive living space. A plate seastead poblated with buoyant  bubble houses would be a extremly safe seastead the rion-antirion pylon solved the engineering on large scale. Maybe a little more ship shaped for mobility. How deeploaded would you go - just a plate or a submerged skyscrapper?

The question is - once you go for a living space bubble for security reasons - why not scale down the seastead structure and go for a breakwater or a lagoon seastead where independent floating units (boats, houseboats, subs, floating living space of all kind) can have a "loose raft up" in open sea.

Wil

concretesubmarine.com

European Submarine Structures AB

This is basicly where the oil/gas industry is going to - when the whole platform goes to hell - a life raft, a boat, is just not enough - they have completly enclosed living space bubbles that can take a direct wave hit, a drop from dozends of meters, a ride trough a oil patch on fire, submerged status,  weeks of isolated drifting at sea - what ever the emergency situation may be - the last resource is always a bunker like bubble.

So why not install your home in such a safe bubble in first place . In the Netherlands a company offers a hotel stay in a "rescue pod hotel" - so "living in the pod" is not so exotic and out of normal after all - many people actually do it already.

Wil

concretesubmarine.com

When we look for role models for bubble living space that can create comfort in the open ocean without the need of giant expensive platforms, we might be inspired by solutions that already exist as "exotic hotel" - below a futuristic snorkel seastead, a underwater hotel, underwater restaurant, massage room in the maledives, utter inn submerged hotel room and platform, survival pod hotel, igloo hotel.

Survival Pod Hotel

These bright orange mod pods anchored in The Hague were part of an art project before being capitalized on as adventurous getaway. Packages range from basic survival with a sleeping bag and food rations to something a bit more James Bond-esque.

The Hotel Kakslauttanen in Finland is in fact an Igloo Village, at which you can have your pick of 20 unique glass and snow igloos for your stay. They aren’t ice houses, but 31 well-maintained log cabins – built from a very special thermo glass that keeps them warmth and comfortable. Because of that, the temperature inside the Igloos is always a normal room temperature and the igloos inhabitants won’t feel any of the polar cold.

Wil

concretesubmarine.com

European Submarine Structures AB

The closest thing to a transparent bubble concept that i have knowledge of are those:

Houston dome,  Eden project, ... they go with (ETFE) foil in aluminum frames - if this kind of bubble living space is strong enough to take a direct wave hit or submerge is doubthful so it might work as the cover of a big plate seastead where direct wave hits to the fragile transparent structure can be excluded. The picture in the middle above does not look like if direct wave hits to the transparent part can be excluded.

Acrylics  is a high strength material that can take direct wave hits but acrylic domes are limited to a 6 foot diameter size and single panels of a few meter are the (expensive) stars of top aquariums - no way to do them in Building size nor city size.

A 6 foot acrylic dome can easyly cost 150.000 USD ... a panel like the picture above a million... seasteading will only happen if real estate costs in squaremeter floorspace are similar to land based real estate prices - this excludes the abundant use of exotic building materials and quantum leap engineering in a seastead very much.

So i fear we have to limit things to concrete shells for practical reasons... - what does not mean that the feel and style of such living space bubbles can not be light, futuristic and wave hit resistent at the same time.

Wil

concretesubmarine.com

European Submarine Structures AB

combine a open ocean aquaculture sistem with a submerged living space for comfort at sea - you get a business and a fine way to run it.

..."how do you connect submerged living space bubbles.."

I repost the link here because it is part of the "submerged living space bubble" thread but popped up on the  "artwork thread"

seasteading.org/interact/forums/community/dreaming-/-crazy-ideas-/-speculation/artwork-share-your-stuff-if-you-dont-

conclusion - there are existing engineering solutions like REMORA rescue sistem and segmented submerged tunnel construction - so it is basicly "off the shelf engineering".

Pictures: Remora / Marmay submerged tunnel

This means that scalability is still possible if a seasteading structure is submerged. If you check the details it is eaven easier to connect a thousand ton  segment to a segmented submerged tunnel than a thousand ton hollow segment to a structure on land. Water allows a much better handling.

Wil

concretesubmarine.com

.

. . . .

Living space bubbles and treehouse spheres - what kind of shape can a living space have...

.

.

.

A solution designed to provide a living space that ensures the survival of humans in open water in all possible conditions on the smallest possible scale is this.

The boat is "almost submersible" able to take a overwash from big storm and freak waves that might sink the mothership. No fancy deck spaces - the living space is inside a rigid shell protection is needed ...

The quality of "can take a wave overwash" is just another word for being able to stand short moments of being submerged.

So for living space in the high seas that can not count on 18m freeboard like a containership - being submersible is a design MUST - being submerged for short periods of time will be a real world status in certain ocean conditions - especially in conditions like shown in this video

So the submersible option should not be considered a "exotic option" any longer in the post draupner wave area.

It should be considered the "only safe and viable" option for ocean colonization for all structures with less then 18m freeboard.

Ships and Yachts have a safety plus by being able to stay out of the path of a severe storm - but any "not sufficient mobile structure" needs to be prepared to be submerged - on purpose or by accident.

Dubai submerged hotel

Air view

http://www.youtube.com/watch?v=f8qvE8zkEeQ

Sea Orbiter Concept Video

A 21st Century 'Nautilus'

'Sea Orbiter' Model: Photo courtesy of SeaOrbiter Project

Part submarine, part research vessel, the 'SeaOrbiter' is currently on view at a Korean expo

It could be an alien spacecraft or a 21st century version of Captain Nemo's Nautilus from Jules Verne "20,000 Leagues Under the Sea," but in fact it's a live-aboard, ocean-going laboratory that could be exploring the seas as soon as late next year, says CNN in a recent news report.

Called the SeaOrbiter , the research vessel is the concept of French architect Jacques Rougerie. Currently the centerpiece of France's pavilion at Expo 2012 in Yeosu, South Korea, it has spent almost 12 years floating around as a mere concept. It recently completed its industrial design phase and construction is slated for October this year.

"All technical issues are resolved, all the modeling is done," says Ariel Fuchs, education and media director of the SeaOrbiter project. "We gathered institutional and industrial support five or six years ago and it's been a real institutional and financial project for the last two years."

It is expected to cost around $43 million and when built, will be 58-meters in height, taller than Nelson's Column, a monument in London. When launched, around 50% of the vessel will be below the water line, allowing for constant underwater study, Fuchs says.

"One of the first users will be the science community," he says. "It's designed to explore the ocean in a new way, mainly spending time under the sea, giving people the opportunity to live under the sea for a very long time, to observe, to undertake research missions, like marine biology, oceanography and climate issues."

Ithaa Underwater Restaurant

Visiting Maldives for the beaches only???

Maybe the World’s First Underwater restaurant, Ithaa could be another reason for the paranomic view of the Indian Ocean.

The Ithaa Restaurant sits 15 feet below the waves of the Indian Ocean, surrounded by a coral reef and encased in clear acrylic, offering diners 270-degrees of panoramic underwater views.

The first aquarium-style underwater restaurant was designed by MJ Murphy in New Zealand and constructed in Singapore with materials provided from the USA. The final design was later shipped to the Maldives.

The restaurant is reached by a wooden walkway from the nearby over-water Sunset Grill Restaurant, and seats just 14 people for exclusive dining with a real difference. To enter the restaurant, visitors climb down a spiral staircase in a thatched pavilion at the end of a jetty. They enter the building, which has a curved roof like a tunnel, from above

After spending a whopping $5 million on the infrastructure and interior designing, the restaurant was acquired by the world famous, Hilton Resorts. By adding this restaurant to the Hilton family, the public’s eyes were drawn towards this spectacle created underwater.

With the huge capital investment on the initial construction, the restaurant has a huge variety of food widely spread of a huge range. The Meals range from USD $120 (lunch for hotel guests) and USD $250 (dinner for hotel guests and Bed & Breakfast meal plan)

It is estimated that the restaurant, which is placed in extreme conditions of the Indian Oceans, will only last for 20 years.

https://way2cit.wordpress.com/2012/07/12/ithaa-underwater-restaurant/

oceanic structures convert in oasis of live - this is already happening with oil rigs.