permanently submerged concrete structures – living space bubble concept
September 12, 2011 at 2:11 pm #1628Ellmer, how do you feel
Ellmer, how do you feel about permanently submerged concrete structures? Basically a modern skyscraper, but it hangs under a platform instead of towering above it.
King Shannon of the Constitutional Monarchy of Logos.September 12, 2011 at 3:43 pm #15467
im down for that
“Leadership and do-ership are not the same thing”September 12, 2011 at 4:10 pm #15472
Is what I was talking about here: http://seasteading.org/interact/forums/community/dreaming-/-crazy-ideas-/-speculation/fundrasing-ideas#comment-17684
Only difference is that I imagine that with two subs instead of one, and four columns, you could build a larger platform above. There’s no reason to believe such a structure, built to be a living space, would have the same maintenance costs of an oil rig, right?September 12, 2011 at 4:12 pm #15474
I really like this concept. When I saw your picture:
it made me think of:
The lily pads in this picture are a great example of how we can design underwater communities. For example, each seastead could be a single lily pad, floating in tandem with others, connected beneath the surface. Or perhaps each pad could be an above-surface infrastructure piece (like solar/wind/rain collection, communications, storage, businesses, what have you) tethered back to the main community below.
Each grouping can be a separate community or nation, close enough for trade and mutual aid, but distanced for the purpose of dynamic geography.September 12, 2011 at 6:48 pm #15481xns wrote:
….how deep can we feasibly make these based on today’s technology?….
Concrete structures in disc shapes with flat bottom and top have reached depths of 70m (the rion-antirion bridge pylon) . Tubular structures that cook down to arch load cases can reach 1400m depth and have been performed to 350m (Troll A).
The sphere can go considerably deeper 1500m and below – what means mining in the mid oceanic ridge – a submerged oil extraction of the brazilian presalt deposits and other projects in the deep sea are already within the reach of standard concrete engineering techniques.
concretesubmarine.comSeptember 12, 2011 at 6:51 pm #15476
I was jus thinking about my hexatoons the other day and how I’d initially planned to stack more hexatoons below as buildings on top got progressively heavier. But then when I want to a few of the newer shopping malls in Singapore, I’d realized that they were about 50% below ground, to the point that the only natural light came from the roof, yet no one seemed bothered by the fact that we were 30m or 100ft below ground.
That’s when I realized that I’d gotten it all wrong. Instead of stacking hexatoons to cope with the ioad of a building, why not just build a square grid of roads and sell the squares in between them? That way whoever owned the space would be responsible for the loading on his own space, without affecting the ones around him. Which is more in line with my libertarian views than a convoluted system of government run “bouyancy tax”.
So I guess the question now is, how deep can we feasibly make these based on today’s technology? If mobility weren’t an issue, and the hexatoons would form a protective beach around the “city”, would the only concern at that point be pressure?
King Shannon of the Constitutional Monarchy of Logos.September 12, 2011 at 6:52 pm #15483
Odd, my photobucket seems bugged, here’s another attempt at a picture
King Shannon of the Constitutional Monarchy of Logos.September 12, 2011 at 7:37 pm #15484
it is probably the most suitable idea for a modular island design – the grid itself does not need to be rigid too….the building could have a loose fit in the building lot… the connectors could be like zephyrheart suggested instead of walkways on the surface make submarine tunnels that can be used in any seastate they would work like the roots of the waterlilly – give some flexibility to avoid excessive stress between islands.September 12, 2011 at 8:46 pm #15485caveden wrote:
….you could build a larger platform above…
The platform above (if there is any) must be considered the “wind weather and wave exposed part” so it is the part where you definitly would not want to be when the 100 year storm comes up. In stead of making it as large as possible i would tend making it as small as possible to keep wind and wave forces low – just to allow a neat port for supply boats – when the weather is fine. The only reason why the oil industry has those platforms is the need for a derrick (drill tower) and a turn table. A seastead does not have such need so why go with a platform design in first place.
The new year wave on draupner platform was 20m high and came out of nothing in a 4m wave ambient. So to have a safe platform above the waves you need to go 20m – better 30m up in the air – that is not a cheap engineering task for affordable living space.
There are two ways to avoid wave impacts – 30m up or 1m down – which one is more economic to achieve?September 12, 2011 at 8:47 pm #15490
Yes, it occurred to me that submarines in these seasteads would be like helicopters in modern cities. But I wanted a rigid connection for the purpose of having an effective road network when the structure was several hundred square kilomters in size. After 15 years of sailing and boating, I’m just don’t like how high-maintenance marine engines are compared to the average car. And besides, I’m a terrestrial animal 😉
PS: Thanks for finding my image Ellmer.
King Shannon of the Constitutional Monarchy of Logos.September 13, 2011 at 7:26 am #15510
The platform above (if there is any) must be considered the “wind weather and wave exposed part”
Do you mean that, even if the platform is just 1,5m above sea level and has no buildings on it (max maybe a cottage that could submerged, where water could enter), only the average wind could make the structure shake?
The new year wave on draupner platform was 20m high and came out of nothing in a 4m wave ambient.
If waves are already on an average of 4m waves, the whole structure should be submerged way before. So I suppose a rogue wave like that wouldn’t make much damage.
Can rogue waves come out of nothing even in calm seas? If that’s the case, then we’re screwed… you cannot expect people to be submerged all the time. If rogue waves can really show up even on calm seas, then the only option left are big, expensive platforms…
So to have a safe platform above the waves you need to go 20m – better 30m up in the air – that is not a cheap engineering task for affordable living space.
There are two ways to avoid wave impacts – 30m up or 1m down – which one is more economic to achieve?
Why not having a platform just 1,5m above the sea level, capable of submerge 1m below when needed?
The main point is: seasteading in its begining will be lonely and tedious. You cannot really compare it with people who live in tiny appartments because those normally are located in big cities. Whoever lives in a tiny appartment/house, normally has lots of things to do outside his home. Lots of entertainement available. In the first years (decades?) of seasteding, there will not be such “city infrastructure”. Going back to land every weekend is probably not an option either since I suppose it would be expensive, take several hours and would kind of defeat the purpose of political independence we seek.
A little open air space to make some parties or just enjoy a beautiful day could help fighting boredom, don’t you think?September 13, 2011 at 5:34 pm #15522caveden wrote:
… average wind could make the structure shake…
The problem is that waves as layed out in the engineering report can reach almost ARBITRARY height and forms when certain rare conditions like the draupner new year event occur. Water has 1 ton per cubic meter. The draupner wave might have contained easyly seveal hundreds of thousands of tons of water moving in a almost arbitrary way with a potential of impacting the structure with inimaginable forces – what thousands of tons of water impacting a structure does we have seen in recent tsunamis – with impacting water walls of only 5 meter height…. imagine a 30m version…
Engineers estimate that something like a draupner event could happen all 200.000 waves – you have about 1 mio waves per year on a seastead – so should count with 5 draupner events per year. Oil platforms in the north sea are built for 20 m design wave height – that means the draupner event scratched the constructive limits of the established oil industry.
So waves are so hard to deal with from a design point of view because we still do not really understand completly what the ocean can bring up in rare occasions. There is a limit how much you can overbuild a structure and still have a viable business plan.
Hydrostatic pressure on a submerged structure on the other hand is easy to predict has no arbitrary behavior, and can be easyly handled in civil engineering. All the MAYOR structural problems like hog, sack, torsion, wave crest impact, horizontal movements just disappear completly when a structure is submerged.
Very big structures like city sized islands can handle draupner events – but until we come to that size that can handle ANY wave – submerged structures might just be the better option due to easy and economic building that comes from the much less hostile conditions below the waves.
Petrobras is already considering submerged oil extraction…
concretesubmarine.comSeptember 14, 2011 at 12:17 am #15528
The idea of an infrastructure that is built and then people bring thier platforms to it is great.
But the issue would be (once again) funding and maintanence (if you ignore the enormous amounts of engineering, building, transporting and final connection). I know we are all talking about building with concrete (we are still talking about building with concrete, right?) but there will still need to be maintanence. And how do you fund this project… I mean look at condos, you have everything right there and still people do not consider them a great investment (even before the house crash). And lets not get into the “connections/raft-up” debate again but if everyone has a different build (size and shape) on the the living structures this would not fit together like a jigsaw puzzle unless you custom built each “enclosure”, then you have to ask how would you utilize the space if that steading decided to move to a new “city-stead”.
On the plus side… if you did create a structure that floated with little to no upward or downward movement then you could utilize the movement of the steads (especially when they were on the surface) to create energy through wave power. As XNS points out the benefit of having physical connection (especially once the “city-stead” size is reach) allows for some form of a transit system to be developed and utilized. Also this structure would be perfect for aquaculture in a number of ways. And a strong structure, like this, would possible allow for a system to be built to create artifical upwells of nutrient rich water from depth for photo and zoo plankton growth and/or help create some sort of low cost cooling system with the same deep water.
JTG423September 14, 2011 at 7:39 am #15532
The problem is that waves as layed out in the engineering report can reach almost ARBITRARY height and forms when certain rare conditions
Are these rare conditions predictable (like “only when the sea is agitated”) or are they competely unpredictable?
If they are unpredictable, then I’m sorry, but the whole idea of small submersibles won’t do it. Who will want to live submersed all the time, during weeks or months? How will these first seasteaders interact among each other? How will they earn a living?
I was assuming the idea of submersibles was good because I thought that most of the time such submarines could stay floating on the surface. If that’s not the case, then TSI got it right: it must start with big, expensive platforms…September 14, 2011 at 10:59 am #15533
but there will still need to be maintanence.
I’m not sure what kind of maintanence you’re referring to, but I can tell you, there wouldn’t be anything you’d do with this structure you wouldn’t do on a normal skyscraper. I’ve read some concerns about biofouling and in my experience, they can & should be ignored for the protection of the structure underneath. Scraping barnacles off concrete will only damage it.
And how do you fund this project…
Like any other construction project, you go to a bank, take a loan. Or if you have enough money, you could just pay a contractor like Ellmer to build it for you.
The whole point of this is to create infrastructure that we DO NOT have to adapt existing building technology to. And because from a realistic point of view, you can’t have a libertarian government that builds every aspect of the country BEFORE immigrants start coming in. We’ve seen some plans that involve massive floating islands with all the rooms and facilities already built, where power and water are already provided. That to me looks like an odd communist utopia, not libertarian.
So to sum it all up, government builds public infrastructure, private industry/citizens build whatever else they want. Which keeps your initial startup relatively low. And you don’t end up paying for hundreds of thousands of lifeboats or server rooms you don’t need at that time.
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