Building ten killometer buildings

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If the population and technology of Earth continue to grow, ten kilometer buildings may be the optimum trade off. I'm thinking pyramid shaped 10 kilometers by 10 kilometers at the ground level, perhaps 11 in the tenth sub-basement, tapering to about one square kilometer at the top above the 3000 th floor. Food could be grown on the sloping south facing wall to an altitude of perhaps 5 kilometers, but not nearly enough for the population of the building which could be perhaps one billion persons, which would be about 200 cubic meters per person. Likely we need to think 1/10 billion persons as up to 99% of the building will be supporting structures, public walkways, stairwells, utilities and other public areas.

The buildings need to be spaced at least 50 kilometers apart to avoid adjacent buildings shading the south wall of adjacent buildings. Some agriculture will be practical between the buildings, but shading will cut the yield even with 70 kilometer spacing. Permission to work at agriculture between the buildings would be a sought after prize for good behavior. More rare would be granting permission to leave the building for other reasons.

We really need to invent the replicator of Star trek so each apartment can be 90% self sufficient, otherwise walkways and roads inside the building take away excessive living space. A partial solution is to have several thousand kilometers of pnumatic tubing (one meter in diameter) in the building to provide transportation for the braver souls. Each tube rider would carry the equivalent of a TV remote control on which they could enter their destination, and select faster or slower. Teflon tites are recommended to reduce possible abrasion on the tube walls. An upward flow of air is definitely need to go to higher floors and will sometimes be needed to to slow your decent. Typically the tubes will move people in both the vertical and horizontal plain, reducing the need for walkways stairwells and elevators. This pressurizes the upper floors, minimizing the oxygen enrichment needed 5 to 10 kilometers above sealevel. Please embellish, refute or comment. Neil

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I did an art project over 20 years ago inwhich I designed a large 6km building UNDERGROUND , called "suburbia" the only energy requirements that were external were pumping water and wastewater out. Elevators were geothermally operated and since drilling in slant and horizontal adits was already a mature science, my little city could connect to the next and so forth. The problem withthe excavated materials was to strain it for aggregate and aluminum as well as any other resource expected.
The only problem I had was the stability. Youll have strength of materials to deal with unless you develop the structure in tetrahedral or hex cells to distribute the bearing.

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Hi farmerman: Tetrahedrons would make few of the floors or ceiling horizontal and few of the walls vertical, unless you are thinking large tetrahedrons. Are you thinking ten meter flats on the hex cells, each about 3 meters tall? That would make nice sized rooms. Would you stager the next level or stack for the whole 6000 meters = 2000 floors? 6000 meters wide would be about 250,000 rooms on each floor, or did I get the wrong mental picture. If the lowest level is at about 2 bar, will high pressure volatiles endanger the humans? How about rock faces throwing schrapnel? If you used pneumatic tube transportation/ventilation you could have about one bar on all levels. Would the wall thickness of the hex cells be more than two meters of reinforced concrete at the lowest level? If you remove heat from a hot rock face does it not cool considerably due the the poor thermal conductivity of rock even at ten watts per square meter being removed? I'm suggesting we can get little geothermal heat unless hot volatiles are available under pressure that persists. Neil

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Rock is one of the best insulators and thermal energy storage materials. The city of Philadelphia is now "mining" the excess heat that buildings have radiated into the subsurface.
The shape that works best for me is hex cells which, even divided in half yield rhombs with a flat floor. And elevators can be stacked around a vertical walled hex tube.
Your pressure and atmospheric gradient would pose as significant a problem as would my thermal gradient . However, the subsurface building can utilize geothermal gradient to drive various service machinery. Since your 10 km building is a little taller than everest. I thought that the advantage of doing this was to use location to change the microclimate by creating artificilal orographic dams. If you locate these buildings in existing desert areas you can squeeze additional moiture out of the atmosphere by having them located just easterly of the desert. It would work in the US because your building would be higher than the western basin and range and coastal mountains. So youd have a wetter climate on the west of your buildings and this could be reclaimed for ag

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Paolo Soleri in the 60's and 70's made some preliminary designs for city-buildings of major populations. A common problem with these structures was not heating, it was cooling. As a result several of the city-buildings incorporated hyperbolic cooling formations within the towers the structure.

Links are ;
Discussion of Works
Arcology and Arcosanti(a work in progress)
Arcology Links and fantasies

Rap

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Hi farmerman: Should I assume the city of Philadelphia is pumping water from about 50 feet below the surface that is several degrees warmer than usual due to heat from the buildings and using it for water warmed heat pumps? Would a similar method work 6 kilometers down to produce higher temperatures? Perhaps you were thinking of leaving hollow hexagon pillars of rock as support columns rather than using reinforced concrete?
I suppose the hyperbolic towers proposed by Paolo Solari were similar in appearance and function to the cooling towers on nuclear power plants? Neil

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neil. The geothermal studies at Philly had used deeper wells from the Cretaceous aged Potomac Fm in what is called the Farrington and Old Bridge sand members. The subcrps of these units are right under the center of Philly and all the runnoff gets channeled as rechrge into the aquifers. This runnoff is heated and picks up additional heat from the nat Thermal gradient (in this area the geothermal gradient is About 30C/km. The interesting thing found was that most of the increase in gradient was gathered around the top of the Farrington sand, (sort of like if you have a vaulted ceiling room and theres a fireplace in that room , all the hot air will be at the ceiling. Even though the water has a density strat, its heat is collected at the tops of formations
There are some places on the planet where the gradient is >50C/km, so the present international drilling project thats going for the mantle is gonna pick up numbers that are much higher. The deepest hole drilled to date is still only about 12Km and that water is stinging hot and very briny with silicates and Carbonates.
Ive read that design basis that rap rap posted and found that the engineering challenges were considered acceptable by his group even in the 60's. We have much better creep resistant metals now and weve got the technology we didnt back then.

I wonder how the environmental impact of creating an artificial rainshadow and orographic effect will be received by the pipples? In my "suburbia" city, We have to recognize the functional limits of deep excavation, thats why I only went about 6 km

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I would think that the rainfall diversion problems would be minimized for the same reasons that Soleri did. A vertical city like an arcology would house people vertically in contrast to the flat cities that we are presently using. When you consider that roughly half of flat cities presently are dedicated to impermeable pavement (something that is largely unnecessary in an arcology) the drainage problems of our present confrontation has a much greater effect.

In addition Soleri’s stance was to but industrial processes (manufacture, waste disposal, material recycling) on the lower level and use processing waste heat for upper level space heating (as necessary). Again though the problems with HVAC, would probable be cooling instead of heat.

There are significant arguments with this new type of a city. Cultural, being the most significant and many of the most immediate IMO would involve transportation and the love of personal vehicle and the internal combustion engine. A transition to this culture; however, may be a transition of one of our more densely populated mega cities such as New York or San Francisco where a car is more of a hindrance than an asset and the personal vehicle objection could already be minimal.

A few years ago, I remember seeing a conception a buckyball covering Manhattan Island. The proposal was that a transparent buckyball over a half a mile in diameter would be tensile rather that compressive, as the trapped heated air would provide support.

However, a year around shirt sleeve environment for a. existing megacity could be used both as a proof and an example of the benefits of the arcology concept.

Now if you could use one of these tower arcologies as a stationary skyhook anchor---the the universe is half as far.

Link for discussion of Macro & Micro Buckyballs

Rap

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I disagree. Soleris concepts , after Ive read them, are non quantitative. Theyre sort of neat ideas but lack substance. (Like I didnt see any references to dimensional analyses)

A vertical city of the size that neil proposes, will definately have climatological consequences, like Chicago or Pittsburgh except 10 times more. Think of a massive building (whose footprint has got to be constructed with strength of materials in mind-ie cant think Buckyball, must think beehive). The single building wil be as tall as Everest at sea level. This will be a huge climatological driver. All winds will be driven up the prevailing wind slope and will wring out any remaining water. One side of the building will be a rainforest and the other a desert.
Building a building that doesnt optimize space (which is what Soleri was about) will just be a FL Wright "mile high+" building. Theres nothing really ecologically sound in a skyskraper.
Maybe such buildings wil make sense in China, where large public works projects can go on for apparently no apparent reasons (picture the 3 gorges dam). I dont think that an arcology is ecologically sound. Anyway , neil and I both recognize that there are significant shortcomings to the structures as proposed
His large pyramid is a weather former and has strength of structure to deal with. My suburbia has limits posed by excavation technologies. My building was a complex of overlapping tauruses, so I had an internal waste of space.However , after talking with an architectural engineering group who shared the labs with me when I took my art degree, they were all concerned with the limitations of span for a deep shaft

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Interesting idea but how practical?

I haven't looked at the math but imagine 1" of rain falling on a slope of that size with no natural water run off capabilities. Now imagine the rarer 12" in 24 hour storm that the structure would have to be capable of handling without a wall of water cascading down onto the surrounding area.

The upkeep on such a structure would be massive because of its size. Would you have to build in sensors to warn of changes in stress from failure of a component? You are not talking a 100 year lifespan or even a 300 year for the structure.

Farmer might be on to something to distribute the weight evenly but there would still be settling of the structure under some parts. 10km by 10km means you won't be building near any fault lines.

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well, any building would have a bearing analysis and would have to be built on stable bedrock (using standard seismic models , I agree that youd need to go to risk zone 1 or lower for either sub or super structures). A 12 inch storm on a 100km footprint would be a 12 inch storm over about 6 sq mi or 3800 acres x 320,000 gal per acre. Lotsa water on an impervious surface.
Since soleri hadnt given any dimensions, Id have to assume that his arcology would have a similar footprint just for material strength.

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OOPS, I meant area not length. 100 sq kilometers is 38 sq miles X 640 acres=24000+ acres times 327000 gallons per acre. Were talkin about 7 billion gallons of water or roughly three times the dailypublic water usage of all ofCalifornia

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I think the general term for runoff water is acrefoot which is about 326,000 gallons but that's picking lint with your number crunch---so lets go with 325K gal.

Another support consideration is building buoyancy.
There are already multistory building built on unstable ground with minimal footing, N'aleans fer 'sample where piles seem to disappear into the Mississippi mud.

In addition, building height is normally linked to elevator speed. In Soleri's highrise arcologies elevators are normally limited to 20 ft/s (about 14mph), so his arcologies are based on a reasonable ground level to top floor time to about 500 seconds (8 min 20 sec). So the building top is about 10,000 feet with somewhere between 500 and 1000 stories.

A 10 km pyramid would be 32000 feet, and a straight shot trip to the top by a similar elevator speed would be 26 min 40 sec. So even simple things like elevator rides are a significant consideration.

BTW, the pyramid building being proposed is more than 33 times the size of an Soleri archology with a population of 1,000,000. So your 10km pyramid could vary well contain the entire population of a state like Pennsylvania, or three Indianas. And it has been shown that a river like the Ohio can easily manage a runoff from such an area.

Rap

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Its not my pyramid, its neils. I always use 327K for pond design we just scale up .
I didnt see anything in you URLs that had any sample designs or quantitation for soleris stuff. There were a couple of dead links and 404 prompts. Everything was conceptual. Where did you get the size and shape stuff?

The discharge 'at a point" for a 12 inch rain would be a problem for a basin for any large building , be it neils, mine, or soleris. A normal drainage basin for a small creek in the east is about 1oo sq miles,so there would need to be major big time Sedimentation and erosion control for design storms of 10 year or more. I dont think neil would propose his buildings in deep, fine grained material. we were talking about placing them in only stable bedrock areas. Actually the Canadian shield is probably the most stable seismically quiet zone on the planet. The pyramid in the high arctic would be a way to bring people in

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Ultima Tower a 10.000 foot involute with a circular footprint 6000 feet in diameter (slightly >1 mi^2).

325, 327 why quibble about the third significant digit---I'm an engineer not an accountant, I just use 325 because I like 325, it's divisible by 5 and 25.` whereas 327 is divisible by 3 and I have a bad karma with 3.

Rap

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farmerman wrote:

I dont think that an arcology is ecologically sound.

So the arcology destroys the ecology around it forcing everyone else to build arcologies to shelter from the ecological devestation. Ironic, eh?

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Parados is correct. I had not considered Earthquakes, nor uneven shifting of the foundation bed rock. Perhaps even optimistic projections for CNT = Carbon nano tubes are insufficent to avoid dangerous stresses from a one centimeter multiple shift of the bed rock. We will have to think less than 10 kilometers tall and/or elaborate load balancing mechanisms that will reduce the usable volume further, until super materials become available.
Typical amounts of rain fall can be collected near impact on the building's west facing surface for the water utility. Storing fifty million tons of water in the upper levels of the building will add significantly to load problems in the lower levels. Perhaps a means to express water out of the upper levels is needed when structural failure becomes probable.
The other faces may suffer water erosion from very rare, very heavy rain fall. Neil

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"In this area the geothermal gradient is about 30C/km. The interesting thing found was that most of the increase in gradient was gathered around the top of the Farrington sand, (sort of like if you have a vaulted ceiling room and theres a fireplace in that room , all the hot air will be at the ceiling. Even though the water has a density strat, its heat is collected at the tops of formations"
~that suggests that the center of Earth may be about the same temperature as the typical temperatures observed at the bottom of the deepest shafts instead of the higher temperatures generally assumed. Neil~

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I didn't find numbers or other details on the Solarie web site, so comparisons are difficult. Hopefully designers of very large structures will mitigate likely problems for nearby land owners. If they don't, they should be required to pay for the losses of their neighbors which they caused, plus all legal fees. Neil

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Quote:

Typical amounts of rain fall can be collected near impact on the building's west facing surface for the water utility. Storing fifty million tons of water in the upper levels of the building will add significantly to load problems in the lower levels. Perhaps a means to express water out of the upper levels is needed when structural failure becomes probable.

At the 10km height you probably won't get large rainfall amounts at the upper levels. You would probably get snow if you get any precipitation at all. The building might have a permanent snow cap.

Interesting to think how weather could be so different for just one building. I don't know enough about weather to know what would really happen to heavily water saturated air that would meet and be driven up a single structure of that size. It wouldn't really react like it would approaching a mountain chain, would it?

You might be able to eliminate some of the problems of shifting bed rock by building in individual columns that are tied together but then you increase your load in those center columns.

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Building ten killometer buildings

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