MINI-BERGSTEAD Model – 1/24 scale
August 29, 2011 at 2:40 pm #15058
I see what you are saying now. Another idea to impove stability would be to build the bottom in the shape of an inverted pyramid, not flat, and ballast the bottom of it (top actually) with lead or iron or extra concrete. I real life application this method will be much cheaper than a water ballast system since you don’t have to build the baffle grid and add a pumping system to increase or reduce the amount of water in your bilge. Unless of course you want the structure to be submergeable or money is no object But if so, you won’t be able to have a “green” area on your main deck, and you will loose a lot in terms of overall esthetic appearance (floating island).
It looks good Shreddy! Nice work man.
PS. The pool need cleaning, lolAugust 29, 2011 at 3:22 pm #15060
of cours ethe pool needs cleaning it was just hours after a hurricane! lol 😉
since the building gouncils’ president was nice enough to let me use the pool, i helped clean it while letting the island float for about an hour and 45 mins.
oooohhhhhhh. now i get why u said an upside down pyramid for the bottom. duh. i feel dumb. im not sure how effective that would be. ill have to think about that. maybe make a model, adduno. but that really would be tough to build and handle it on land, dont u think?
“Leadership and do-ership are not the same thing”August 29, 2011 at 3:59 pm #15063
shred…just a few points – fragility of structures increases with the size – this is the reason why a beetle can fall from a 30 story building and survive while a elephant falling from 1meter breaks his bones. Titanic touched the iceberg so slightly that passengers could hardly feel the contact inside the hull…a dinghy made in the same technique (steel with rivet) can be thrown from a third floor without taking serious damage.
To get a clear idea of wave bhavior you need to simulate waves with a length 2-3 times the size of the model (which corresponds to ocean waves compared to a full sized “berg”… the video of the ecuador base gives a much better picture of the realities…movements – maybe you can simulate the right type of waves putting a row of 5 people on one side of the pool making kind of push ups on the side . A natural lake with with wavelength of half a meter to 2 meter might get you a more apropiate test site for how a house sized square structure behaves in real sized ocean waves.
…and aehm… i am not competing with you – nor trying to shoot your ideas down – just try to bring a few points for consideration…i would be happy if you could build something like that in real size…keep pushing – keep experimenting…
concretesubmarine.comAugust 29, 2011 at 4:31 pm #15067
I’m going to have to get to work on my model!August 29, 2011 at 4:55 pm #15069
i’ll say i appreciate your approach in that response.
this comparison between the berg and the coast guard base is still a bit grinding for me because, to my understanding, that barge is just as simple as, well, my first physical model. it has a flat bottom with little to no ballast. theres hardly any wave attenuation on it, plus the center of gravity is too high. of course it rolls and pitches. but science provides many simple techniques to modify such a design and make it more useful (without being 100m square). on any surface floating structure there will be some motion, but how can we use known science and physics to make a bergstead at least as stable as it can be. and the coast guard base is not a good example for that.
here’s some of the techniques…
i think between the pyramid, the baffles, stabilizer fins, and they even make a gyroscope that comes as a pre-built unit – just install, and hook it to electrical systems. given all that, i refuse to believe the berg design would be too rough. there just has to be some way – u know im a little bone-headed.
help me out on this Emmett.
thank u Wohlwend -now im feeling a bit bashful. thank you dude!
“Leadership and do-ership are not the same thing”August 29, 2011 at 8:46 pm #15072
the best way to take movement out would be to connect house sized floats by beams to a much bigger “grid” as the wave movement relevant size would not be a single unit but the grid itself that could exceed 100m diameter easyly – to keep forces in a manageable range the beams must have some flexibility (enough stiffness to dampen movements – enough flexibility to avoid damage in really big waves) – the fatigue problem in the beams is manageable – about 1 mio bending cycles per year – what is within the range of many concrete structures as bridges and highrise buildings.
The problem is, a grid of dozends of interconnected houses achieving the necessary stability is no “small scale start up” at all…
What matters in terms of movement in ocean waves is not the form of of the float but its size compared to the ocean waves wavelenght – if it is bigger than the waves (length) it will not move at all – if it is smaller it will follow the wave (track the wave) and move a lot … make a couple of experiments with the model with that in mind watching it at different wavelenght going trough – you will understand it better.
WilAugust 30, 2011 at 7:20 am #15087
I’m going to have to get to work on my model!
we’ll all get to seasteading.
calm aware desire choice love express intuit moveSeptember 1, 2011 at 3:34 pm #15155September 2, 2011 at 4:38 am #15175
i’ve been researching ballast systems to make this berg submerge. i found something on this page about 2/3 of the way down that looks good and might be reasonably affordable. its called a Recirculating Compressed Air Ballast System: RCABS.
“Leadership and do-ership are not the same thing”September 2, 2011 at 1:26 pm #15178
Add some diagonal reinforcing. Any wave action could bend it into a romboid and pop off the bottom. Otherwise it looks good. May I suggest
extending the walls down below the bottom deck/hull floor. This would couple a large mass on water trapped under the deck to the deck leading to more inertial mass without much more boayany mass in the vessel. All burg ship designs should have two or more airlock exits to the deck but most can be just hatches.
For everyone’s information I was involved with the original Oceania Project in a small way. I’m also in several space organisations. And I have a Degree in sustainable Development, sustainable agriculture and renewable energy,water and sewerage.September 2, 2011 at 3:13 pm #15180
thats very thoughtful, Mr. Bruce. (we both have 2 first names). the design does call for a full length and width compartment below the interior living space which provides the ballast area, and a dry place for mechanical systems. i def love the airlock idea. i hadnt thought of that. but i have been thinking about fire safety recently (especially when a berg is submerged!). there should prob be at least 2 points of egress. i also think it may be necessary to build another full-length and width compartment above the living area to hold water and/or fire suppression material. fire safety is a HUGE concern. the moment a small fire breaks out when ur submerged is very scary to think about. oxygen will be gone in a flash and if theres a storm above, its not intended to surface in those conditions.
you said to add diagonal reinforcing. did you mean to build that into the steel that’s set into the concrete? might be a good idea. instead of a normal rebar layout, use a cross-hatch design that would resist lateral torsion.
“Leadership and do-ership are not the same thing”September 2, 2011 at 3:52 pm #15182
don’t overengineer it – keep in mind : if you can not compete with land bases real estate prices (living space per cubic meter) a design is useless because the business plan becomes “not feasible”.September 2, 2011 at 6:13 pm #15187
Ellmer has a valid point. i learned how to do some amazing stuff with restoring old houses back in the 90’s. then that stuff went out of style there was no market any more for it. gotta target the product to the consumer base.
Ellmer what can we do to ballast a model vs. what can we do to ballast a full-size one. did u have ballast in ur submarines? how much r u willing to discuss it, i dont want to dig too deep into ur proprietary know-how, but theres SOOOO many different ways to do it. im just wondering what would work best right here right now with this project.
“Leadership and do-ership are not the same thing”September 2, 2011 at 11:36 pm #15199
not bad for a guy that never worked with concrete a day in his life, ehh?
“Leadership and do-ership are not the same thing”September 3, 2011 at 4:09 am #15202
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