Herman-Melville | A large enough floating structure would not be rocked by normal waves. What is the most economical route to a structure of this class? |
Herman-Melville | As a thought experiment, consider a colossal ferrocement sphere floating around in the ocean. Its enormous weight and size mean that even the largest waves hardly move it at all. |
Jesrad | This is the route I’ve been considering recently with the flattened truncated pyramid design. Being not built for speed but strength and durability out of hundreds of tons of ferrocement, a large and massive enough structure has a very large period of rolling and heaving, and is pretty much immune to waves. Building it more economically means using cheap and massive material, and distributing the maximum of that mass at the sides (it should be hollow in the middle, but reinforced enough not to collapse or fail). A sphere is not ideal, because the stresses from waves are concentrated on a shallow band and inexistent at the top and bottom: a cylinder is more adequate IMO. |
Carl-Pålsson | - A really large flat box out of ferrocement. Make the thickness (height) large enough so that the biggest (within reason) waves cannot wash over it or drop lower than the bottom of the box and you should be fine, no?
- Like so: http://wiki.seasteading.org/index.php/Image:Bigbox.PNG
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Jesrad | It is possible also to use thin metal spars to rise the “ground” from the box and leave a gap for waves to pass through, like this. |
Patri | Pastor Jason wants the wave height vs. Belize discussion from here moved to this thread, and I still don’t understand his response to Lasse, so I will ask my question here. He wrote: Pastor_Jason wrote: Lasse, you are right about wave height being a HUGE factor in seastead design. Seasteads I imagine will need to be able to deal with very large waves as they will travel the globe. This is a factor for seastead design. This question has NOTHING to do with where a group of ‘steaders settle to work on seasteading designs and technology. Either way, the point is moot. Belize has one of the largest barrier reefs in the world sheltering her waters. Wave height rarely rises above 1 meter and is often at half that height. … So to summarize: Wave height is a factor for seastead design and has nothing to do with the location of a seastead outpost. Even if this factor was determined to be an important one, Belize has low waves (especially where we’re looking) so the point is moot either way
To translate this into a general claim, this is basically saying that the target operational location of a seastead has nothing at all do with where you construct the seastead. This makes no sense to me at all. I mean, you can research a seastead wherever you want, you can research the infrastructure wherever you want. But once you build a seastead, you need to get it to the operational location. Waves aside, the further you are from that location, the harder it will be. And taking waves into account, it is an even bigger problem. If you build a seastead for 5m waves in the Baltic, and you build it near the Baltic, no problem to bring it to the final location. If you build it in the Caribbean, how do you get it to the Baltic? You either have to pay a lot of money to a shipper, or you have to take it all the way across the Atlantic…and its big waves. Having reef-sheltered waters doesn’t help this problem at all. If you build in Belize, you are going to build Caribbean seasteads. The Caribbean is a nice place, and this isn’t necessarily a bad idea, but it is absurd to think that construction location is unrelated to operational location. |
Hephaeston | That there is no intention of final placement of the seastead being in a ‘safe’(r?) area. That doing so would restrict freedom of … um evasion? too much. That is with mobility (to escape conflict) being of prime importance there is no intention of building a final product that would be restricted to certain areas. So once it’s assumed that the thing will be built to withstand 100 year storms and big rogues, it doesn’t really matter where you build it, obviously, excepting access to the open ocean. The preference in building locations would come down to minimal government interference, relatively easy access to major infrastructure, local materials cost and availability … well all the stuff that’s been gone over here before. Or eventual placement … which is *less* of a concern if it’s big enough to handle everything. Obviously it would make it more expensive and/or take a rather long time. Personally I think we’ll end up sailing the things, but I do find myself sadly lacking the requisite naval architecture degree to not be talking out of my. But the reasons to put it particular places strike me as rather ephemeral for now. Who knows what the political climate will be toward this entire movement generally, let alone according to particular naval powers. Those seem like the big issues to me as opposed to particular proximity to specific shipping routes, cities, etc. Obviously sitting off NY or Kyoto/Tokyo would be a gigantic boon economically, but I’m guessing they wouldn’t be too happy about it for too long. And there are shipping routes almost *everywhere.* Like I said, I’m guessing, but it is *my* take on it as well. I’m sure Pastor_Jason will chime in with his actual perspective  . |
DM8954 | Well, there are other factors to consider. What are land prices on the Baltic like? How is the tax situation? How does the weather compare? Are there any safety concerns to be aware of? How do the resources stack up? For example: seafood available in the closed off black sea, Vs. the more open (more diverse?) waters of the Caribbean; number of solar days; average wind speed; etc.. It also comes down to which goal you’re aiming at. If we’re worried about building a seastead that can only handle relatively calm waters, Besides, with EEZs in effect, not even the Mediterranean has fully international waters. So, since the level of freedom is equal among the sheltered waters of the world, you can compare them on other factors, including personal preference. You only get the full benefits of the high seas along with their dangers. The Caribbean is a Sea because it is partially protected and enclosed from the Atlantic by a chain of islands. The main weather related downside is the potential for a Hurricane (or, more accurately, a dozen or so per season). Good weather forecasting can help you avoid the worst of it, most of the time. That’s not to mention the fact that both the season and the most likely trajectories of these storms are predictable. Put yourself out of the main storm paths during those months and hunker down for any extra waves that blow in. So, that brings us back to comparing the merits of the nearby land again. Is the cheaper land or some other point of preference worth the risk of those few months? That’s up to each seasteader, I think. Besides, sheltered water is only the infancy for seasteading. We only need lakes, bays, lagoons, and seas until we achieve open ocean safety. Again, that’s still the main point, isn’t it? Keep improving the design until you can leave the lagoon, then keep going until you can leave the sea. During Storm season, get back to the lagoon (or even dry land)… unless you want to use it as an opportunity to do tests on a design improvement and fully sheltered water just won’t help you. Outpost residents might just come to rename ‘Hurricane Season’ to ‘Testing Season’. After all, half-scale or quarter-scale models in hurricane conditions might even be a close match for the North Pacific during a 100-year storm. |
Pastor_Jason | In short, I agree with Heph. “Seasteads” are made for open deep water ocean and will operate within international waters. They will be strong enough for large waves and should be designed to survive a rogue wave. These vessels will also be mobile and thus would be able to slowly travel anywhere in the world… so shipping costs can be ignored. I think what Lasse is talking about is something along the lines of a “Baystead” which will stay in a single location and not have the capability of dealing with large waves. These designs will not operate in international waters and while they are a good step toward seasteading, are not “seasteads” by Patri’s definition. Perhaps that clears up the confusion. Seastead Outpost: Belize will be focused on building “Seasteads”, not baysteads (though we might make a couple in the process… who knows?!). Live Well! -Jason |
Eelco | Jesrad wrote: This is the route I’ve been considering recently with the flattened truncated pyramid design. Being not built for speed but strength and durability out of hundreds of tons of ferrocement, a large and massive enough structure has a very large period of rolling and heaving, and is pretty much immune to waves. Building it more economically means using cheap and massive material, and distributing the maximum of that mass at the sides (it should be hollow in the middle, but reinforced enough not to collapse or fail). A sphere is not ideal, because the stresses from waves are concentrated on a shallow band and inexistent at the top and bottom: a cylinder is more adequate IMO. Ive been working on something that starts from pretty much the same reasoning as this. Big beefy hollow concrete cylinder, displacing lots of water, basalt on the bottom, and you have something rather steady. It moves up and down with the waves, but thats tolerable. Ive been working out the details recently, and they are far exceeding my expectations. It doesnt economically scale down to single-family size, but as a foundation for a medium sized high-rise building (10x200m2), its really quite cheap and effective. And in terms of possible catastrophic failure modes, it beats living anywhere on land. Having multiple of such massive-displacement structures connected in the right way opens some further interesting possibilities. Mobility other than by tugboat obviously not being one of them, but ive never seen that as realistic or necesary anyway. Will post pictures, motivation, and my order of magnitude estimates soon. |
OCEANOPOLIS | Yes, size(read mass) indeed matters. But as important in dealing w/waves is design and seamanship. Design is very important. A 20 tons matchbox floating structure and a 20t 48′ Hans Christian sailboat are very far from being the same. While both might survive a hurricane structurley, when the smoke clears, the sailboat is still floating, even though hit hard broadside and capsized, it came back in 1 min. because the hull is self righting. The matchbox is up side down and you have a salvage operation going on now. Actually you can kiss it good bye if you are 2000 miles offshore, unless,…you are ready to spend $500,000.00 (or more) in order to hire an ocean going barge w/a crane on it to attempt to turn it over. Seamanship and electronic navigation. Maybe the most important of all. The boat might be built as a tank, w/the right design, but if the captain doesnt have a clue how to deal w/bad weather he’s doomed. Part of it too, is having good elecronics aboard, radar and a satellite weather station being very important. If you see a storm coming or you are running into one, turn around and RUN,…baby, run. Ahoy, O. |
Jesrad | Ive been working on something that starts from pretty much the same reasoning as this. Big beefy hollow concrete cylinder, displacing lots of water, basalt on the bottom, and you have something rather steady. It moves up and down with the waves, but thats tolerable. … Will post pictures, motivation, and my order of magnitude estimates soon. Great ! Can’t wait for more details  |
cthulhujunior | Hi. I’m not very experienced in naval architecture, so if anything here has already been said and disproved, please let me know. I’ve been talking to some people who do design things for the sea, and they say the trick is to build it longer than the wavelength of the waves. This is why cruise ships are so freaking huge. Thus, for single-family ‘steads, I’ve had the idea of a long, flat platform that’s kept light for buoyancy and has everything spaced out. Basically, it would be a large, broad shell (say, ferrocement) with various living modules all spread out on a single “story.” However, this is rather inefficient, especially for a single family. Not only is the size cost prohibitive, but you’d have one or two people traversing the whole length of a cruise ship (figuring this a good baseline size, since they can withstand the waves) just to go from one end of the platform to another. Now, it seems to me, the problem with giant waves is that they tip platforms and, depending on how steep the waves are, capsize them. Hurricanes are essentially strong winds with strong waves and rain. Because of the size limitations, I’ve been a fan of neglecting size and going for counter-balance platform tipping systems- basically, if the platform tips forward, the system shifts the weight to tip it backward. As for surviving the winds and rain, an open sea should keep the platform from running into anything, and a good seal on all the doors should keep the rain from causing too much damage. Plus, a smaller structure would require less power to navigate away from bad storms and be easier for a single person to control. Tying all the platforms together in a loose net would keep ‘steads from hitting each other. Then again, my inexperience may prevent me from knowing the full dangers of hurricanes on the open ocean. I hope this helps, any thoughts would be well appreciated. Thanks. |
Eelco | Hi. I’m not very experienced in naval architecture, so if anything here has already been said and disproved, please let me know. I’ve been talking to some people who do design things for the sea, and they say the trick is to build it longer than the wavelength of the waves. This is why cruise ships are so freaking huge. Thus, for single-family ‘steads, I’ve had the idea of a long, flat platform that’s kept light for buoyancy and has everything spaced out. Basically, it would be a large, broad shell (say, ferrocement) with various living modules all spread out on a single “story.” However, this is rather inefficient, especially for a single family. Not only is the size cost prohibitive, but you’d have one or two people traversing the whole length of a cruise ship (figuring this a good baseline size, since they can withstand the waves) just to go from one end of the platform to another. Waves can be defeated in several ways. Going big is one of them, although a limited one: there is always a wave bigger than your boat. Essentially, small waves are not an issue, because you simply bash them out of the way, and big waves are not an issue, because if a wave is much longer than your footprint, you can just have it pass under you. Its the waves of a size comparable to your seastead which are the problem: they wont just pass under you, and their attempts to pass through you are bothersome, to say the least. They are especially apt at rocking you, or tipping you over completely. I think ive found a nice way of countering that, which is low tech, does not require energy input, and looks good on all accounts, but its a techincal argument, and i havnt made it presentable yet. More on that later. |
Eelco | I just started a wiki on the design ive been talking about. Its not quite doing it justice yet, but making everything presentable is a time-consuming process. For what its worth: http://wiki.seasteading.org/index.php/Megalith |
i_is_j_smith 1090 days ago.
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