Floating Hexagon Tubes Linked Into Clusters
September 5, 2011 at 4:43 pm #1615
Floating Hexagon Tubes Linked Into Clusters
see photo here – http://outpostalpha.com/forum/viewtopic.php?f=24&t=117 I dont get how to link a photo here…
Problem is how to design a easy to replicate structure that is expandable to large scale to create floating communities.
Cost effective for the average person, sure I would love a large floating platform with oodles of space but we have dry space as a premium. 80 yards of concrete is about $8000 so call this design $16k by the time hatches and windows are incorporated. Yielding approximately 508 sq’ of private space per tube and 166 sq’ of public space on top.
Looking at a cross section of a honeycomb you can see the beautiful layout of hexagonal cells making up their structure.
Think of a cross section of a beehive hundreds of hexagonal cells
Imagine a hexagonal tube say 16′ in diameter which would yield 14′ inside with 1′ thick walls, this structure could be 4 floors below and a sun deck above. 1′ thick floors would give 7′ head space for each floor.
The manufacturing could be done easily by slip forming 4′ to 8′ sections inner and outer mold. going up from the bottom and a block tackle, pulley bucket system to pour concrete into the casting. At each floor joint cast a circular groove round the inside perimeter to come back after the tube is made to cast floors inside and make them lock in place mechanically.
Make a watertight hatch for each floor.
Transport tube laying down in water once on site flood the 1-2 lower floors causing the bottom of the tube to sink and the top to be raised, clamp, strap, bolt, to additional tubes to form a large platform, then equally pump out the water to make all floors usable once a substantial overall platform width is achieved.
Each tube would be its own apartment. Other tubes would be mechanical tubes for electric generation, storage and distribution, yet more tubes for sanitation. Everything completely modular.
My math approximations.
8’x8’x8′ triangle = 27.7128 sq’ x 6 triangles in a hexagon = 166.2768 sq’ per floor
7’x7’x7′ triangle = 21.2176 sq’ x 6 triangles in a hexagon = 127.3056 sq’ per floor
Concrete per linear’ of outer wall 166.2768-127.3056 = 38.9712 cu’
38.9712 x 40 feet tall 1558.848 cu’ of concrete
Concrete per inner floor space 127.3056 x 5 floors = 636.528 cu’
Total concrete use on 1′ thick floors and walls
1558.848 + 636.528 = 2195.376 cu’ / 27 = 80.1991 cu/yards
Concrete Weight 80.1991 x 3900 lbs = 212776.49 lbs
Total displacement of structure volume
166.2768 sq’ * 40 tall = 6651.072 cu’ x 62.42796 = 415212.8567
Total buoyancy in pounds 415212.8567
Total weight in pounds 212776.49
10380.3214 pounds of buoyancy per foot of structure = 20.4980′ draft with approx 19.5′ of free-board. This structure would not stay upright very well on its own without a substantial amount of ballast, however it can compensate by being connected to many other attached structures for lateral stability. Also you could flood the bottom floor to use as temporary ballast while awaiting a large enough community to form.
See concept scale photo, Give me some opinions please!
ref:September 5, 2011 at 5:46 pm #15245
i admit i havent read that whole diatribe – but my first impression of the picture is that it wont work. my reasoning is that the individual tubes cannot be fastened to each other in such a way that they will flex. if they do not move independently from each other, they gonna break. i know my square shape looks ‘too simple’, but it was chosen after considering hexagons for a several reasons.
instead of ‘clamp, strap, bolt’, try my trailer hitch concept.
“Leadership and do-ership are not the same thing”September 5, 2011 at 7:10 pm #15247
I dont want the tubes to move, they could simply be next to eachother with a strap around em all in place with friction? there is so much friction area between units i dont think they will slide around, could even cast in some keyways or pegs.
If one can work on its own, why not 2-5-10-100 no concrete structure will flex, yours wont flex why would you think mine would?September 5, 2011 at 8:05 pm #15250
oy… no, concrete does not flex. thats why it needs a linkage that allows for movement. if the water was always still it would not be a problem. but the water often has waves, which can be get very high in a storm. therefore, your structure will not always have even support.
“Leadership and do-ership are not the same thing”September 5, 2011 at 11:29 pm #15253
Once they are bolted together it would be like 1 large structure that is 40′ thick of honeycomb design with floors every 8 feet as addl bracing..
The structure woul dbe 18-19′ above the waterline and even if a wave were to crash over the top, if it is all concrete with hatches closed, then no problem.
When a wave hits once side, the energy will dispurse around the perimiter and through the entire structure, wea re talking about 200,000 + lbs per module 1/2 in the water, could even ballast it down even more if needed.
Having each module tied to another module creates potential for flex and independant high point loading for stress, in my concept the load is spread out.
Any actual engineers have an opinion?September 6, 2011 at 2:12 pm #15264
ellmer – http://yook3.comParticipant
building honeycomb structures in floating concrete is a frequently used technique. I have to agree with ocean, most walls in the structure end to be double this imposes much higher cost than a simple shell structure like a plate. Where you do not only avoid to enclose the living space all side with double walls – but reduce the building cost to a single wall (floor) avoiding side and deck walls. This reduces building cost compared to segmented honeycomb a factor 12 and compared to a square cube structure still a factor 6.
No doubth that segmented honeycomb building will keep having a place in floating concrete structures – but there are still more economic solutions easier to implement and more versatile to handle.
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 /
I do not belive that any form of “closed tiling lego concept” will get seasteading on track – it will probably be a “non design” wild float out of many concepts at the same time that allows a come together of anything that floats.
As the older particiapants of this forum know i have tested segmented honeycomb and plate concepts in our test site here in cartagena.
So i can directly compare building and workhour cost of the structures – i prefer a simple clear shell as suggested in the bubble living space concept thread – it provides most BANG for the BUG – your dome concept would be such a shell – so it seems promising.
concretesubmarine.comSeptember 6, 2011 at 8:07 pm #15262
you’ll be better off financially to just build a big ferrocement hull since you’ll save a lot on material. It will be lighter, less draft =more living space above the waterline and much cheaper.
But, if every hexagon is a small living bubble, it might work.
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