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imagine a geodesic dome constructed on the equator. If it has a diameter of roughly 500 miles, then its roof would be in geosynchronus orbit. Could such a structure be built? —Preceding unsigned comment added by 184.108.40.206 (talk) 16:33, 17 June 2008 (UTC)
This entry is flat out wrong from the definition go.Two16 20:13 Jan 9, 2003 (UTC)
I'm a bit of a Fuller Scholar, if nobody has any objections I will take a kick at the article. I think that I can do a good job because I understand the mathematics behind geodesic domes.
Is there is anything I need to know? Two16 17:31 Jan 13, 2003 (UTC)
I'm not too surprised by the first comment above, even though I don't actually know. Will the eventual article point out to laymen that some vertices in a geodesic dome are intersections of five edges although most are intersections of six edges? Michael Hardy 17:33 Jan 13, 2003 (UTC)
- Why, yes. Yes it must.
use of 1st person in the Chord Factors area
What's with the Martian?
Is there really a reason to obfuscate this article with gobblygook (jiədɛzɪk/jiədizɪk dəʊm)? There's maybe 15 people in the world who can read that, and maybe 2 of them don't already know the proper pronunciation of "geodesic dome". Sheesh.
- well, many non-native speakers of English (myself included) find that useful. However... is this pronunciation correct? I would expect it to start with /ʤ/, certainly not with /j/ rado 08:08, 21 Jun 2005 (UTC)
- Um, "maybe 15 people in the world," eh? Heck of a small world you come from. My world has got more serious dictionary users than that (both native and non-native speakers), to say nothing of the phoneticians, ethnolinguists, speech pathologists, singers, and hobbyist nerds....
- But seriously. Even native speakers of English (specifically, me) have been grateful to find pronunciation information on Wikipedia. I'm sure the people who put it there didn't specifically anticipate my need for it. But there it was when I needed it ... and it's a lot better in IPA than in the wretched, condescending, and sometimes ambiguous "phonetic spellings" that well-meaning amateurs are constantly devising. ("JEE-uh-DESS-ick DOAM", anyone?) Don't confuse your ignorance of a tool with its lack of utility.
- And yes, it ought to be /ʤ/ -- easy mistake for an English speaker to make. eritain 07:03, 18 December 2005 (UTC)
More detail on the dome and the snowplow would be helpful; it reads like a web-rumor, though it may well be true. Is it in fact associated with the University? Disambiguation uncertain, choosing Princeton, New Jersey. Septentrionalis 20:27, 10 July 2005 (UTC)
I found a reference to this in Kenner, Hugh. "Geodesic Math and How to Use It" 1976, 2nd edition paperback 2003. The Regents of the University of California. Page 22, with the quote "A ninety-strut 40-foot Tensegrity sphere erected at Princeton University in 1953 was struck by a snowplow at point near the ground and exhibited component failure (a bent strut) high up on the other side, just 180[degrees] from the point of impact." --Phays 01:12, 28 June 2007 (UTC)
It has been about a month since I posted this, and having heard nothing I removed the "reference needed" item.--Phays 03:02, 24 July 2007 (UTC)
It is the only man made structure that gets stronger as it increases in size.
- What does this mean, and can it be proven? --Heron 21:03, 20 August 2005 (UTC)
My guess is: what was meant by that is that larger geodesic structures tend to be higher frequency. (Ergo: more struts in them.) The reason they're strong in the first place is (in part) that they are triangulated; but also (in part) that stresses imposed on them are distributed. The latter point is just as important. Buckminster Fuller explained all that.
Presuming of course that had been properly designed and constructed: in a larger structure, the stresses imposed in one spot would have more pathways to travel, than in the case of a smaller (presumably lower frequency) dome. Stress it in one spot...the stress tends to distribute itself over the whole thing.
Intuitively...I think more pathways for stress would (indeed) imply stronger, or more resilent. It would take more force to break one. Even if you broke one in one spot, in a big dome it wouldn't matter as much as in a smaller dome. The other struts would simply assume the load, over a broad area. Probably you could half cave one by running an airplane into it and it would still stand, much better than the World Trade Center towers stood when they got hit. They were inherently designed to collapse as soon as the upper floors began to collapse. Those events, we now know, assured total destruction. I seriously doubt that a very large geodesic dome would behave that way.
You'd really need to test one with an engineering program to know for sure. But I believe the principle is valid. At least, I doubt one would get any weaker with size, as long as the dihedral angles hadn't gotten so close to 180 degrees that a force (or even its own weight) might cause it to buckle. (Because if it was super-huge then the vertices would not really be points on the surface of a sphere; extremely low angles would mean they were more like points on a plane, and thus lose the natural benefit of triangulation.)
But in really big domes, that potential route of structural failure is normally handled (as in the case of any large stadium roof) by making the outer skin three dimensional, i.e. also triangulated in terms of its depth. Two layers. The skin struts can't move then. They're locked in place. A double-layer dome is inherently very strong.
It's a superb system for engineering large structures. I doubt there is any upper limit to how big a geodesic dome could be, as long as the struts and connectors - (particularly the connectors) - were sufficiently well engineered and adequately strong. It's possible that with super-strong materials (like carbon nanotubes or something similar), one could construct a geodesic dome big enough to cover an entire large city, and yet still strong enough to withstand a hurricane, or maybe even a tornado.
I mean...what's holding on the roof of most buildings? Not much. Bloody nails. Normal construction is a weak method. They know that in Florida. It's goodbye home sweet home every time they have a serious hurricane. Yet those dummies keep rebuilding the same way. What a good deal for builders. Happy day. They build 'em up; nature knocks 'em down. More work for them. In a geodesic dome, the entire thing is holding itself together. One struts supports the next. But remove some of them...it doesn't care much.
It's fascinating. I once built a 3-freguency geodesic sphere out of light balsa wood, about a meter in diameter. When it was complete I squeezed it between my hands. It didn't want to move. It didn't flex. I never tried squeezing it with one strut missing. But I know they're very strong. I could actually feel that. But I would never start on a mega-project to cover a city with one without having a computer and a reliable engineering program first tell me that it would work. Analyzing the potential failure modes in a structure with about a hundred million struts could take quite a while. It would help to use a supercomputer. Then it might only take a month to analyze it. :) Stellar-TO 02:34, 6 November 2005 (UTC)
- Thank you, Stellar-TO. Would you agree, then, that the statement I quoted at the top of this section is too general to be useful? First of all, I would take out the 'only', since it's probably impossible to prove that. A better version, based on what you have just said, might be:
- A geodesic dome is an unusual form of construction in that its resilience increases with size, because of the increasing number of struts; although at very large sizes it must be reinforced by adding one or more concentric layers of struts.'
- Would that be more accurate?
- Incidentally, I wonder if you have seen a wickerwork football used to play soccer. I have seen these used by children in less industrialised countries, and it's amazing how such a fragile-looking structure can resist being kicked around all day. --Heron 10:39, 6 November 2005 (UTC)
Um...I'd say that claim is a bit too general to be useful. Where's the engineering/mathematical evidence to support it? An engineer might claims that a very large bridge is stronger than a smaller one. And he'd probably be right. So he'd have proven that assertion wrong. (Or his expertise would itself carry some weight.) What is the definition of "strength"? The load it can carry in proportion to its weight? I'm not an engineer. I think the statement that it is the ONLY structure that gets stronger with size is probably WRONG. If there are other structures where bigger means stronger, then it is wrong. Why even have it in the article? I think it's adequate to give a reason why large domes are inherently stronger. I think the claim that it's the only one should be removed from the article, because that sounds questionable to me.
What I would say is: "Higher frequency domes are inherently stronger because there are more pathways (struts) to distribute imposed stress." (It's really a matter of frequency rather than size.)
I know wicker is a very strong material. I wasn't aware that it was used for making soccer balls. But thanks for bringing that to my attention. Interesting. That info I can use! :) Stellar-TO 04:19, 7 November 2005 (UTC)
The text in the article is still quite misleading. Lines like "Domes are very strong, actually getting stronger as they are constructed larger" are either flat-out incorrect, if referring to strength per element, (see square-cube law), or are correct but meaningless (any structure if scaled up has higher absolute strength; stresses just scale up faster). --Christopher Thomas 02:53, 16 August 2006 (UTC)
" I would never start on a mega-project to cover a city with one without having a computer and a reliable engineering program first tell me that it would work" - you don't say :))) EVERY engineering structure these days is done in CAD ... — Preceding unsigned comment added by 220.127.116.11 (talk) 22:05, 12 September 2012 (UTC)
I see that the highly misleading statement is still up there ...
I changed the statement about 'every triangle is different'. No, they are not all different; there are several different sizes, but each one of them repeats many times — Preceding unsigned comment added by 18.104.22.168 (talk) 22:08, 12 September 2012 (UTC)
Space usability, slope of roof
Can someone explain this?
- The dome shape leaves most of the interior surface unusable because of the sharply sloping roof lines. For example, in a 20 foot tall dome, only the bottom 8 feet or so are really usable.
'Cuz I don't get it. In a 20-foot-tall room, only the bottom eight feet or so are really usable—that's about as high as I can reach, how 'bout you? We use the rest of the space by dividing it into two floors, and obviously the second floor in a dome is going to be much smaller than the first—but that is because the roof angles are shallow near the apex, not because they're steep. Am I even on the right track toward a clarification here, or did the author mean something completely different? eritain 07:17, 18 December 2005 (UTC)
I think the term "unusable" is ridiculous. That is an *assumption*, not fact. Who says you can use only the bottom eight feet??? The dome itself is just the shell. You can pretty much build as you please within that shell, as long as it's solid.
I once did a quite detailed design for a large 3/4 dome, about ten meters in diameter. I also figured out how the interior floor space would be laid out. (A 20 foot dome could easily accommodate two floors, not just one.) I had three floors in my 30 foot dome design. The floors were attached to the outer frame and to a chimney/staircase at the center. I found that the entire space in that volume could be used! If you have only one floor, that's a different matter. Maybe that is "inefficient". But I'd say that would be someone who didn't know how to build efficiently. That would not be the fault of the dome; it would be the fault of the designer!
As I see it - and I contemplated those problems a lot - there is nothing in geodesic domes which makes them inherently space-inefficient. I didn't see any technical problems in terms of building cabinets or using that interior space, either. Top floor - you put in some cabinets around...you could create vertical walls if they're comforting...a nice veranda around...I found no serious problems. All one would need would be (1) some patience, (2) the proper tools, (3) the skill to cut wood at peculiar angles, and of course (4) some building experience would be good. Much of the interior space could be fitted out so it almost looked like a standard home, inside, if you wanted it to. There is no need for walls to be sloping everywhere if you don't want them to be. So even talk about "interior angles" is an *assumption*. That's to assume that you're going to leave the exterior shell as your walls. That's not necessarily the case.
Your average carpenter may not have the patience (or skill) to deal with other than 90 degrees. But a lot of the saws, you can cut wood accurately at any angle. I'd say anyone who lacks patience, imagination or math ability should stay away from domes.
My regret is I never got around to actually building one, based on my design. But I was pretty sure it would end up being a very solid, durable, funky, practical home. Put some spikes on the vertices and paint it a warm pastel color...a 3/4 dome parked beside the ocean could look a lot like a big sea urchin. I thought that would be so cool. That would be a home that got a stared at a lot, and people on ferries cruising by would be saying, wow, that's neat.
Domes look great on paper or on computer screens.22.214.171.124 (talk) 20:11, 30 October 2009 (UTC) The curse of the world is people who lack imagination. I think Bucky Fuller bitched about it, too. :) Stellar-TO 02:47, 20 December 2005 (UTC)
- The curse of the dome is that rectangles fit together in ways that circles don't. I've had a go at clarifying this. ...dave souza 10:01, 11 January 2006 (UTC)
Criticism of geodesic domes
I could add a few. They cannot easily be built out of natural materials, so the frequent label of 'ecobuilding' is rarely accurate for domes. If they are not on entirely flat ground, some of the top panels may be even closer to horizontal than usual, increasing the risk of leaks. If domes are built out of a wooden frame, covered by plastic sheet or fabric, like the greenhouse described, the fabric must be either shaped to fit the dome precisely (meaning lots of seams, weakening the fabric and increasing the chances of leaks. A rectangular piece of fabric must be consierably larger than the surface of the dome to cover it effectively, it is also difficult to attach canvas or plastic to a dome securely without it flapping around in the wind. A dome is all roof, making waterproofing difficult. Rain water runs down to the base of a dome, which will quickly cause wood at the base of the dome to rot, and this water may also flow under the base of the dome. It is very difficult to collect rainwater that falls on a dome. Rectangular buildings have overhanging roofs to keep walls, doors and windows dry.
The comment that shingles are the best way to waterproof a dome needs to be justified. according to George Oakes http://www.shelterpub.com/_shelter/domebuilder%27s_blues.html: "Everybody who has ever roofed a dome with cedar shakes has wound up with soggy sheetrock. The only practical answer is composition shingles, which are easy to nail down but which “burn out” in about 10 years and have to be replaced. This is quite a major concern when your house is two thirds roof. You can go expensive and buy fiberglass-base composition shingle, which last about 30 years. Even so, when they have to be replaced, the cost will be disproportionately more than for the guy who built a long, rectangular roof."
I have heard that a skin can be made out of sections of plastic shaped like orange segments, heat sealed together. This does not precisely fit a geodesic dome.
Oakes lists the "chief technical drawbacks" based on his own experience:
"1. The only kind of insulation you can legally use in a dome kit is super-expensive, flammable, poisonous, and unbelievably labor-intensive to install. 2. The very shape of the house makes it difficult to conform to code requirements for placement of sewer vents and chimneys. 3. Domes are difficult to roof. And if not roofed exceptionally well, they will leak like a sieve. 4. All building materials come in rectangular shapes off the shelf. They have to be cut to fit triangular and other non-standard shapes. Scrap from cutting -i.e., waste — ranges from about 10 percent to 20 percent, depending on the type of material, of what you paid for. 5. Domes require about twice as much sparking tape and electrical cable as conventional houses of similar size. Cable costs quite a bit, and labor costs are doubled, too. 6. Foundations are critical. You can get away with a lot in conventional houses, but not with a dome. 7. Fire escapes are problematical, they’re required, and they’re expensive. Windows conforming to code can cost anywhere from 5 to 15 times as much as windows in conventional houses. "
He adds others (in addition to the ones already discussed) such as heating (hot air stratifies at the top), meeting plumbing regulations, foundations, ventilation, leaky windows (especially upstairs windows which cannot be left open if there is any chance of rain), light and sound bounce around the dome, problems with chimneys and regulations, hanging pictures is hard etc.
http://www.shelterpub.com/_shelter/domes_rectangles.html compares rectangular and dome shaped buildings and includes yet more problems. Including, materials (a restricted range of high grade materials can be used for domes, traditional buildings can be built with a greater range of materials), later expansion of a dome is problematic, as is partitioning.
Also recommend http://www.shelterpub.com/_shelter/smart_but_not_wise.html
The article keeps stating that cost is a major issue but if I understand geodesic domes correctly construction costs should be considerably lower than a regular home. Am I correct?
Yes, you are correct... the bigger a Geodesic Dome gets, the cheaper it becomes per amount of volume compared to a regular building.--Bridgeengineer05282 22:31, 14 September 2006 (UTC)
re: The problem is that all current construction materials and codes assume recangular-based houses. Plywood comes in rectangular sheets; windows are rectangular; angle-brackets are all 90 degrees. None of these work with a dome, requiring lots of custom fabrication and/or wasted materials. Some of these problems stem from the assumption that houses must be made primarily of wood but many of them are inherent. If building materials were mass-produced in dome-appropriate forms, then domes would be cheaper. Once you get to very large structures, i.e. skyscrapers, the economics of scale kick back in and domes really are cheaper for the volume contained.
Just a heads-up - two of the links point to pages on www.desertdomes.com --Benplaut 07:00, 27 April 2006 (UTC)
Someone added this comment to the article. Disputes should be on the talk page, not in the article, so I moved it here until it can be checked out:
www.telacommunications.com/geodome.htm Dr. Walter Bauersfeld Chief Designer of the Carl Zeiss works at Jena, East Gemany designed the Geodesic Dome in 1922 for a Planetarium. The Fuller Patent is a Photocopy with Fuller's name substituted.
--Heron 13:52, 21 August 2006 (UTC)
- The cited URL doesn't mention any patents, and may have been revised since the comment was added. I don't know if the part about the Fuller patent is true, but it wouldn't be surprising, since it's well known that the Allies confiscated (~ stole) much German industrial knowledge and intellectual property after both World Wars, even going so far as to assign "patents" to such purloined knowledge. For those familiar with the history of Revolution Helicopter, it's clear that such shenanigans occur even outside the context of war spoils, when an inventor is slow or hasn't the funds to register his design internationally. —QuicksilverT @ 01:13, 8 February 2008 (UTC)
Hey wikidudes, I've been doing all types of engineering related science projects lately, and if you ever need any advice about any topic of a science project, please e-mail me at: firstname.lastname@example.org Thanks...
So far, I've done these topics:
Are wind tunnels really effective? = turned out great... made exact replica's of different bird wings. Then used dry-ice vapors to show the aerodynamical differences of each wing.
--Bridgeengineer05282 22:38, 14 September 2006 (UTC)
Chord factors and frequency
there's some confusion here between chord factor (having to do with the length of each strut) and frequency (having to do with how many times the platonic solid is being subdivided)
It's easy to get bogged down in a lot of detail: does the user want to know the math involved in constructing a geodesic dome? Would it be sufficient to just get the 'recipe', a list of chord factors? Or does it even matter that one can build a dome out of tetrahedrons, octahedrons, or icosohedrons? Anansi133 01:42, 1 December 2006 (UTC)
List of geodesic domes
This article contains a list of large geodesic domes according to the Buckminster Fuller Institute. However, at least one of the domes on that list, the Tacoma Dome, is definitely *not* a geodesic dome. (Check out the Tacoma Dome article.) The BFI list is labeled only as being the ten largest domes -- not "geodesic domes" -- in the world.
So... Wikipedia says this is a list of geodesic domes, BFI says it's a list of not-necessarily-geodesic domes. Wikipedia is implying that the Tacoma Dome is geodesic; it is not.
I'm new to editing Wikipedia pages. What is the right way to resolve this misleading implication? 19:58, 3 July 2007 (UTC) Compass98155 (David D.)
Incorrect information in this post
I am new to working with Wikipedia but this article has some startlingly incorrect information in it, particularly under the "Disadvantages" section. I'd like to know what process to go through to remove and correct information in this section without stepping on someone's toes. I am a geodesic dome expert with 30+ years designing / building domes. I have been involved in well over a thousand dome projects, and I feel I could more accurately author this.—Preceding unsigned comment added by Okvomit (talk • contribs) 19:39, 17 July 2007
Please, have at it. I would appreciate it if you log any significant changes and their justification to this discussion page, so that you can get a discussion of any caustic topics. Your expertise would be appreciated. --Phays 03:02, 24 July 2007 (UTC)
Largest domes section
Anyone willing to undertake the rather unromantic task of cleaning up the Largest domes section? My chief concern is that the text appears to refer to , where there are only 10 domes listed. Of course, this information may be quite dated, and if there is a more recent source available, then it should be referenced. (And the domes should be put into decreasing order of size, which they appear not to be.) If a source cannot be found, then I suggest that the list be restored to its original form. Silly rabbit (talk) 06:44, 8 January 2008 (UTC)
There is what appears to be off-topic material in the Methods_of_construction section — references to concrete and foam plastic domes. This is construction that is typically used on non-geodesic domes. —QuicksilverT @ 01:13, 8 February 2008 (UTC)
Stronger as it gets larger?
Awhile back there were some skeptical comments about the article's claim that geodesic domes get stronger as they get larger (and indeed that they are the only man-made structures with this property). There was quite a bit of arm-waving, but no one really answered the question (as far as I can tell). On the face of it, the claim that geodesic domes get stronger as they get larger doesn't even make sense. It would have to be clarified before it could even achieve the status of being wrong. I suggest that if no one can back up that statement, it should be removed. Any objections? 126.96.36.199 (talk) 21:29, 2 July 2008 (UTC)
- 'A fuller explanation: The Synergetic Geometry of R. Buckminster Fuller' by Amy C Edmonson supports this claim on page xv of the introduction. From a brief skim through the rest of the book, it appears accurate but I haven't seen any direct justification for the claim. Robin S (talk) 14:32, 22 October 2008 (UTC)
tidy up of external links as of the Wikipedia external linking policy:
Dome mountian: not accessible
A big list of large span structures: indirectly related
Geodesic polyhedra: repeated link
solardome: commercial site
Origami geoshere: indirectly related
Simple geodesic dome construction video: not unique
New projects with geodesic structures: commercial site
bucky's dome: indirectly related
Photographs of Dome Construction on Camp Lake, Ontario: not a recognized authority
Geometry Dome: not a recognized authority
Creating Paper and Plastic Domes: not a recognized authority
Not sure about the 5.1mb pdf document would that have accessibility issues?
(Pauly1060 (talk) 01:32, 11 October 2008 (UTC))
- I've also noted (after someone cleaned up the list) that the link to "The Mathematics behind Geodesic Domes and Spaceframes" (TekCad) is apparently dead. From online searching, it appears that TekStar (the offering company) is defunct, and TekCad is no longer available (nor are any of their former webpages.) I shall delete the link. Apddraig (talk) 23:30, 18 December 2008 (UTC)
I have a page on my own site which would serve as a reference for Bono's DOME program. Wikipedia's COI guidelines suggest that another editor should decide on the suitability of the link: DOME Antiprism (talk) 08:48, 16 September 2011 (UTC)
Hi. Just wondering how the Climatron dome, built in 1960, could be inspired by a 1972 science-fiction film. I imagine this caption needs to be changed? —Preceding unsigned comment added by Willie D (talk • contribs) 06:24, 24 October 2008 (UTC)
"Methods of construction" -- oddly definite claims
The "Methods of construction" section begins "Wooden domes have a hole drilled in the width of a strut. A stainless steel band locks the strut's hole to a steel pipe." Well, no. That's one way to do it, but hardly the only or best way. And the claim that stainless steel bands are "the way" that wooden domes are locked together is absurd; there's an infinite number of materials that could be used. The entry goes on to also make such definitive claims about domes made from other materials. To wit: "Panelized domes are constructed of separately-framed timbers covered in plywood." No, again. Panelized domes can be made of any one of countless materials, from styrofoam covered with paper to solid gold covered with titanium. Someone needs to go in and Wikify this section. Anyone? Bricology (talk) 02:39, 1 June 2009 (UTC)
What code would this be?
picture of dome home on Forest&Cherry
Does the article claims that numbers "2 sin(nu/2)" are decimals.???
First things first: This is a really good GIF. I enjoyed watching it spin until I put the brakes on and tried to use it to explain geodesic domes to the uninitiated. Now I see the curious "twisted" in the file information. I checked the companion illustration and it is also twisted. I wonder how they got twisted but more importantly, why? I was trying to use the frames of the animation for educational purposes and found myself hanging by a thread and losing the respect of my students when nothing I told them about geodesic domes was borne out by the illustration. I think this should be removed from the geodesic dome page. It simply is not an illustration of a geodesic dome. It is a bad joke in a serious encyclopedia. You will not immediately see what I am complaining about unless you can stop the animation and trace from the center of one of the pentagons (which are the apexes of the basic icosahedron) along the line which exits the pentagon at any of the five apexes. You should encounter the center of another pentagon, but you will not in this illustration. If you look carefully as your tracing passes three triangles, you will see you have arrived at an edge of another pentagon. This is how the geodesic sphere is "twisted". It is not an illustration of a geodesic dome.
- Geodesic domes are often described as Class I, II, or III according to their relationship with a base polyhedron. The animation is a Class III model based on an icosahedron. The parameters of 3 and 1 mean that you can travel between the base vertices (the 5-way vertices) by stepping 3 edges in one direction then 1 edge in another. Class III domes don't seemed to be used much in construction (e.g. Skylights Types), nor even mentioned very much. There is overlap with the T Number in virology, the table in the Capsid article shows Class I (k=0), Class II (h=k) and Class III (h=/=k with k=/=0) geodesic spheres.Antiprism (talk) 12:08, 30 September 2011 (UTC)
There is so much that I think I know that I do not actually know. It is always a pleasant surprise to find someone who knows something I never heard of, and better yet, is willing to share it with me. Thanks, Antiprism. Anewcharliega (talk) 08:41, 4 April 2013 (UTC)