GEODESIC DOMES

GEODESIC DOMES
Informational paper by Giulio Neri
Contents:
01
From Wikipedia, the free encyclopedia
02
History
03
Advantages of domes
041
Metal Domes
04
04.2
Dome materials
Wood
04.2-1
Plywood Domes
04.3
Concrete domes
This paper wants to give basic information about geodesic domes and the situation on geodesic dome
production in the world market.
These sheets are a collage from the internet. Therefore personal add-ons will be written bold.
This collection was not made for advertising porpoise. Names and Companies are quoted for further
research. I picked up what I thought might be best representative in the world net market of 2006.
http://www.tfwpa.com/gdh/
Geodesic Dome Homes are the logical future. Even though Geodesic Dome Homes have been
around for decades; they have not received the proper attention for an alternative home choice
until the 90's. Their popularity has increased tremendously due to the demand for stronger, better
built, more flexible, and energy efficient homes, not to mention the domes beauty and uniqueness
and most importantly its cost effectiveness in comparison to the conventional homes on the
market.
01.From Wikipedia, the free encyclopedia
geodesic dome (IPA: /ʤiədɛsɪk/ or /ʤiədizɪk/ /dəʊm/) is an almost spherical structure based on
a network of struts arranged on great circles (geodesics) lying on the surface of a sphere. The
geodesics intersect to form triangular elements that create local triangular rigidity and distribute
the stress. It is the only man made structure that gets stronger as it increases in size.
Of all known structures, a geodesic dome has the highest ratio of enclosed volume to weight.
Geodesic domes are far stronger as units than the individual struts would suggest. It is common
for a new dome to reach a "critical mass" during construction, shift slightly, and lift any attached
scaffolding from the ground.
Geodesic domes are designed by taking a Platonic solid, such as an icosahedron, and then filling
each face with a regular pattern of triangles bulged out so that their vertices lie in the surface of a
sphere. The trick is that the sub-pattern of triangles should create "geodesics", great circles to
distribute stress across the structure.
There is reason to believe that geodesic construction can be effectively extended to any shape,
although it works best in shapes that lack corners to concentrate stress.
02 History
R. Buckminster Fuller (aka Buckminster Fuller) developed and named
the geodesic dome from field experiments with Kenneth Snelson and
others at Black Mountain College in the late 1940's. Researchers have
found antecedent experiments like the 1913 geodesic planetarium dome
at the Carl Zeiss plant in Jena, Germany, but it was Fuller that exploited,
patented, and developed the idea.
The geodesic dome appealed to Fuller because it was extremely strong
for its weight, its "omnitriangulated" surface provided an inherently
stable structure, and because a sphere encloses the greatest volume
for the least surface area. Fuller had hopes that the geodesic dome
would help address the postwar housing crisis. This was in line with his
prior hopes for both versions of the Dymaxion House.
From an engineering perspective geodesic domes are far superior to traditional, right-angle postand-beam constructions. Traditional constructions are a far less efficient use of materials, are far
heavier, are less stable, and rely on gravity to stand up.
However, there are also some notable drawbacks to geodesic constructions as well. Although
extremely strong, domes react to external stresses in ways that confound traditional engineering.
Some tensegrity structures will retain their shape and contract evenly when stressed on the
outside, and some don't. For example, a dome built at Princeton, New Jersey was hit by a
snowplow. The stress was transmitted through the structure, and popped out struts on the
opposite side. To this day, the behavior of tension and compression forces in the different
varieties of geodesic structures is not well understood. So, traditionally trained structural
engineers may not be able to adequately predict their performance and safety.
The dome was successfully adopted for specialized industrial use, such as the 1958 Union Tank
Car Company dome near Baton Rouge, Louisiana and specialty buildings like the Henry Kaiser
dome, auditoriums, weather observatories, and storage facilities. The dome was soon breaking
records for covered surface, enclosed volume, and construction speed. Leveraging the geodesic
dome's stability, the US Air Force experimented with helicopter-deliverable units. The dome was
introduced to a wider audience at Expo '67 the Montreal, Canada World's Fair as part of the
American Pavilion. The structure's covering later burned, but the structure itself still stands and,
under the name Biosphère, currently houses an interpretive museum about the Saint Lawrence
River. A dome was constructed at the South Pole in 1975 where its resistance to snow and wind
loads is important.
03 Advantages of domes
They are very strong, and get stronger the larger they get. The basic structure can be erected very
quickly from lightweight pieces by a small crew. Domes as large as fifty meters have been
constructed in the wilderness from rough materials without a crane. The dome is also
aerodynamic, so it withstands considerable wind loads, such as those created by hurricanes. Solar
heating is possible by placing an arc of windows across the dome: the more heating needed the
wider the arc should be, to encompass more of the year.
Many companies exist today that sell both dome plans and frame material with instructions
designed simply enough for owners to build themselves, and many do to make the net cost lower
than standard construction homes. Construction techniques have improved based on real world
feedback over sixty years and many newer dome homes can resolve nearly all of the disadvantages
that were more true of the early dome homes.
04 Dome materials
Domes can be built in many varieties of materials.
The most used are:
-Metal
-Wood
-Concrete
04.1 Metal Domes
Metal structured domes are normally used for Military, commercial use and to cover Sport areas.
It is very simple and quick to assemble and it’s costs for heating and cooling are very
advantageus.
Especially metal covered domes show very good the
air exchange inside the dome.
a) In cold situations, like at night, the shell is
cold. Hot air raises from the middle of the
dome. The cool surface of the dome
refreshes the air which falls to the bottom.
b) Hot temperatures in hot climates raise the
temperature on the dome outside surface.
The hot air raises along the wall of the shell
and falls, after refreshment in the middle.
c) This phenomenon can be catalized by an
opening on the top and som openings in the
bottom of the dome. The Venturi effect let’s
fresh new air inside from the top, while
exhausted air and dust is expelled from the
bottom.
04.2 Wood
Wooden dome structures are the most used dome structures for housing. The building and design
was developed since the 1980’s. After more than 20 years of building and designing, various
companies can guarantee their Manu facts for over 25 up to 60 years lifetime.
The amount of positive testimoniances in the internet demonstrates somehow the positive
developing of Fullers ideas.
Full kits for dome houses are sold all over the world.
Dome homes are mostly built in the United States and are sold by American companies such as:
Albata Geodesics
900 C.R. 795
Montevallo, Al. 35115
http://domebuilder.wecre8.com/index.htm
Timberline Geodesics
2015 Blake Street
Berkeley, CA 94704
1-800-DOME-HOME
1-800-366-3466
(510) 849-4481
FAX (510) 849-3265
http://www.domehome.com/
Wooden structures are easy to build, because they require light equipment.
The only tools you will need are:
•
•
•
•
•
Socket Wrenches
Hammers
Ladders
Scaffolding
Nail Gun
With some experience big roofs can bey quickly build from 2-3
people.
John was able to build this, together with his wife in 2-3 weeks
. Wooden domes are erected over cement or cement and brick fundaments. The plumbing is
installed as well. Vertical walls on the lover level increase the volume and usable surface in the
house.
Econodomes
www.decahome .com
Econodomes sells a very easy-to-assemble system, which requires good handwork, but less
expensive, metallic elements.
A house like this is sold in the U.S.A for 25000, - USD.
04.2-1 Plywood Domes
Plywood domes are very profitable
in the sense that the plywood
sheets don’t need to be cut or
modified. Secondly the positioning
of the sheets is advantageous for
water impermeadility.
The same system is applicable with
steel panels.
Steve Miller is a pioneer of this
construction method. He writes on his site “Formactive”:
http://www.sover.net/~triorbtl/index1.html
In 1972 I first became interested in geodesic domes. There was little information
available at the time, beyond an article in Popular Science for pool covers. A group
of domebuilders in California published Domebook 2 in 1972, which I bought
right away (Domebook 1 came out earlier, but must have been rare. I have never
seen a copy.). I studied it tirelessly, trying to get my mind around figures based
not on squares nor even with a gravity orientation.
That book was jammed with useful
data; however, I was alarmed by the
domes they were promoting.
Although the geometry was a
challenge for me, I had worked as a
roofer during summers in high
school and college, with shingles and
flashing and roofing cement, and
knew a lot more about roofing than
anyone in Domebook 2 seemed to
know. They were building hemispherical walls, with open seams facing the sky,
and trying to seal them with new plastic products. They were working with
inadequate budgets, and third rate materials, and making skylights out of vinyl. (It
is important to understand that though domes can be made with a small amount
of material compared to other methods, the materials must be of high quality).
The only geodesic domes that had a chance were the offbeat metal and concrete
domes that the writer/builders themselves condemned for their lack of aesthetic
appeal. Aesthetics played a primary role in these domes. The builders were
obviously artists; the book was a tour de force of creative domebuilding, covering
a surprising amount of ground. Many domebuilders of
today were inspired by this book.
The design they were promoting, with dimension lumber
frames and sheathed with cut out, nailed on plywood
triangles, is still the most popular residential geodesic dome type, made with the
figures printed in that old Popular Science article for the pool covers. The domes
built today for homes are mostly refined versions of the leaky hemispherical walls
of the early days, utterly dependent on composite shingles to shed water.
In the back of Domebook 2 was a
list of Fuller's geodesic patents. A
few years later I sent for several of
them, and was thrilled by the
brilliance of the methods described.
The ideas laid down in the patents
were being ignored. The "SelfStrutted Geodesic Plydome"
grabbed me. I had worked with
plywood in the building trades, and
had felt the strength potential in
thin, bent plywood, although I had not thought of how to exploit it very well. The
pictures of plydomes in The Dymaxion World of Buckminster Fuller showed domes
made of full sheets of quarter inch plywood bolted together in an overlapping
"shingle" pattern that got me going on a research project that started in 1981,
and continued until recently, when I and my family moved into one. The
overlapping plywood sheets make domes that shed water as soon as the dome is
assembled. The basic building is inherently watershedding, and no shingles are
needed. The tensional continuity is nearly perfect, unlike the primitive nailing on
of plywood triangles. The shell is so strong that often no frame is needed; I have
found a hex-pent frame to be advisable on my larger diameter plydomes,
fastened on the inside after assembly. A hex- pent frame has 1/3 as many struts
as a triangulated frame, and is used to increase rigidity. It is also handy for
stapling on bubblepack insulation.
I found out that working from a patent can be a risky business- the plydome
patent was a minefield for me. The domes I built were quite daring. I wanted to
know just how strong a dome had to be to be useful, and wanted to accentuate
the tensile qualities, which are beautifully described in Synergetics 1, in the
context of balloons (Section 760.00). When my largest dome was in a state of
partial collapse from a sudden heavy snow load, and I was jacking the undamaged
section out, I thought of a simple mathematical formula to link geodesics to
pneumatics. Fuller mentioned the usefulness of 'failure point research' in getting
past the excessive overbuilding and compressive, crystalline structuring that
plagues geodesic construction. I ran with that idea, and deliberately made domes
that could possibly collapse. Then I carefully added supplemental structuring to
bring them to usefulness, when possible. Some of them never got that far.
Almost all of my load testing has been with snowfalls. The 42' dome weighed
about 2 tons and after a 30" snowfall was carrying 10 tons of snow. That was
before I installed a thin 2v frame within the 6v dome in the hopes it could bear a
5' load someday.
Insulating in our plydome home followed a similar failure point pattern, where I
am using an experimental approach based on tight sealing and air chambers
within the ideal aerodynamic shape, with thoughtful use of vents. While
experimenting with domes the most frequent question posed to me was, "how will
you insulate them?" I studied the patents for the Dymaxion Deployment Unit, the
Dymaxion Dwelling Machine, and the Fly's Eye (Critical Path) to understand the
Bucky Fuller approach. The method I came up with is most like the postwar
Dwelling Machine design (1940's) which used tightly sealed chambers with a
rubber curtain hanging inside the airspace. Metal connectors are minimal, and
fastened in wood frames. The rubber curtains are updated to 5/16 aluminized
bubblepack (Reflectix). Although the bottom part of the house is unfinished- the
insulation shows, and so it lacks the important inside air chamber in the lower
3/8 of the sphere- but our house is using an exceptionally small amount of fuel
in the winter in Vermont, just a few gallons a day. This is with an R value of less
than 10. In the summer we have no trees to shade the house, and a full exposure
all year. The metal ventilator works as a parasol to keep sun off the top of the
dome, and a rope operated trap door in the top of the ceiling enables air
movement in and out of the top of the dome. This has been perfectly satisfactory
for 3 years.
So far our plydome is working well. I am not offering it as a kit or plans, since I
am not an engineer and doubt any engineer would endorse my designs- meaning
building codes will find them unacceptable. Also, the process is familiar to me
after years of practice, but would be a difficult process for the beginner to
attempt.
Steve Miller
04.3 Concrete domes
To build concrete domes is an old science, art and challenge to which many architects in history
have been interested.
Today concrete shells are easy and quick to build. This is done
with an innovative system created by the Monolithic institute in
Italy, Texas U.S.A.
www.monolithic.com
The system is very simple: it bases on an air form on which is
sprayed or layered concrete. Monoliyhic posseses the patent of this
airform building process. Anyway, according to Buckminster Fullers
ideals, Monolithic often works and helps in it’ s best way, non profit projects.
Monolithic has already done non profit projects and had recently some projects in India. As it
states in the site:
“The Need
In countries such as the Union of South Africa, Korea, Mexico, Ghana, Philippines, Honduras and
others, the need for low-cost housing is staggering. Reported housing shortages range from
500,000 to 1,000,000. Can you imagine the effort it takes to
initiate a project for 1,000, 10,000 or 100,000 units? Example:
Building 25,000 homes in a timely manner, with a goal of 20
completed units per day, for 250 days per year, requires 5 years.
The logistics are enormous and the financing presents another
problem. In many areas, families must maintain themselves with an
annual income that wouldn’t pay an average dry-cleaning bill. Fire
is also a danger, and fire protection usually is limited. Other hazards impinging on quality housing
include earthquakes, hurricanes, rot and decay.
Our Solution
The UN has set guidelines for what they deem to be adequate housing. We have built a prototype
home at the Monolithic headquarters meeting their
requirements. It is a simple, 28-square-meter (314 square feet)
house which utilizes approximately $1000 worth of basic
material. This (EcoShell) concrete steel-reinforced dome
measures 6 meters (20 feet) in diameter and 3 meters (10 feet)
in height. It consists of openings for a door and window in front
and two small windows in the rear.
Cost
For this example, we are assuming there is some sort of existing infrastructure near the building
site. The cost of extending simple roads, simple water, simple sewage with sewage treatment,
including land costs will run approximately $2000 per unit. We add $1000 per unit for the raw
cost of the structure. That includes the Airforms. (Since we expect to build one hundred homes
using one Airform, the project will require ten Airforms at $3,000 each). To that, we add $2000 for
interior finish, appliances, basic equipment and general overhead. A thousand units, therefore, will
cost around $5 million.
.
Monolithic has also build a village and some shelters in India
Monolithic domes are disaster secure. Concrete and steel is needed and very low technical
precision.
BENEFITS OF MONOLITHIC DOME STRUCTURES
The cost of building, operating, and maintaining conventionally constructed buildings continues to increase.
Much of
conventional construction is the same as or similar to1950s construction technology. The air form technology
method of
construction and insulation is the newest feature of the concrete thin-shell construction technology. Air
forming was first used
as a construction method about 30 years ago. This technology and construction is now called the Monolithic
Dome.
The cost for energy to heat and cool conventional buildings is also dramatically increasing. Consequently,
many building
owners are considering alternative construction systems and methods. A Monolithic Dome structure has
several advantages.
Here are some of the benefits we have discovered. Air formed concrete thin-shell structures:
• Are based on design principles of concrete thin-shells that have been in existence for centuries. Ancient
buildings such as
Haggis Sophia in Turkey and the Pantheon in Rome are domed buildings that were built based on
comparable design
principles and have lasted for centuries.
• Can resist a “Force 5 Tornado(300 miles/hour winds)” and provide maximum safety for the building
inhabitants. This
structure will be the most stable, reliable, and durable in the high wind conditions in Kansas.
• Require the least amount of material to enclose the largest amount of space and fit the requirements for
“green” buildings
and for sustainable buildings.
• Are typically the strongest, best-insulated, and least expensive free span structures.
• Can be designed so the thermal mass of the concrete shell’s interior environment reduces the cost of
heating and cooling
by up to 40-60% (depending on size and use of the concrete shell structure) compared to other conventional
construction.
• Can be erected in much less time than any other conventional construction.
This concrete thin shell structure can be erected in 4 to 6 months or even less time depending on the
weather and other
working conditions. This construction time may not include the rest of the project construction.
• Provide a building enclosure that protects other building trades work (except site work) from inclement
weather so the
project construction work can continue without delays and extra cost.
• Suspend lighting and other important features from the thin shell.
• Have good acoustics for all types of events.
How to Build a Monolithic Dome
Step One
The Monolithic Dome starts as a concrete ring foundation,
reinforced with steel rebar. Vertical steel bars embedded in the
ring later attached to the steel reinforcing of the dome itself.
Small domes may use an integrated floor/ring foundation.
Otherwise, the floor is poured after completion of the dome.
Step Two
An Airform -- fabricated to the proper shape and size -- is
placed on the ring base. Using blower fans, it is inflated and the
Airform creates the shape of the structure to be completed. The
fans run throughout construction of the dome.
Step Three
Polyurethane foam is applied to the interior surface of the
Airform. Entrance into the air-structure is made through a
double door airlock which keeps the air-pressure inside at a
constant level. Approximately three inches of foam is applied.
The foam is also the base for attaching the steel reinforcing
rebar.
Step Four
Steel reinforcing rebar is attached to the foam using a specially
engineered layout of hoop (horizontal) and vertical steel rebar.
Small domes need small diameter bars with wide spacing.
Large domes require larger bars with closer spacing.
Step Five
Shotcrete -- a special spray mix of concrete -- is applied to the
interior surface of the dome. The steel rebar is embedded in the
concrete and when about three inches of shotcrete is applied,
the Monolithic Dome is finished. The blower fans are shut off
after the concrete is set.
The Fly Eye Dome
Informational paper by Giulio Neri
Contents:
01
About the Fly eye Dome
03
Ideas for developing the Fly eye Module
02
Known built Fly eye Domes
This paper wants to give basic information about geodesic domes and the situation on geodesic dome
production in the world market.
These sheets are a collage from the internet. Therefore personal add-ons will be written bold.
This collection was not made for advertising porpoise. Names and Companies are quoted for further
research. I picked up what I thought might be best representative in the world net market of 2007.
01 About the Fly eye Dome
Abstract from:
http://www.ideafinder.com/history/inventions/geodesicdome.htm
Bucky with Fly's Eye dome (taken in Colorado).
This picture was submitted by Jay Salsburg who receivedthe
picture from John Warren in 1979 during their work on Dr.
Fuller's Rigid Tensegrity Fly's Eye Model for Sir Norman
Foster.
R. Buckminster Fuller was truly a man ahead of his time. Fuller was a practical philosopher who
demonstrated his ideas as inventions that he called “artifacts.” Some were built as prototypes; others exist
only on paper; all he felt were technically viable. His most famous invention was the Geodesic Dome
developed in 1954. Its design created the lightest, strongest, and most cost-effective structure ever devised.
The geodesic dome is able to cover more space without internal supports than any other enclosure.
The geodesic dome is able to cover more space without internal supports than any other enclosure. It
becomes proportionally lighter and stronger the larger it is. The geodesic dome is a breakthrough in shelter,
not only in cost-effectiveness, but in ease of construction. In 1957, a geodesic dome auditorium in Honolulu
was put up so quickly that 22 hours after the parts were delivered, a full house was comfortably seated
inside enjoying a concert. Today over 300,000 domes dot the globe.
Plastic and fiberglass "radomes" house delicate radar equipment along the Arctic perimeter, and weather
stations withstand winds up to 180 mph. Corrugated metal domes have given shelter to families in Africa, at
a cost of $350 per dome. The U.S. Marine Corps hailed the geodesic dome as "the first basic improvement
in mobile military shelter in 2,600 years." The world’s largest aluminum clear-span structure is at Long Beach
Harbor. Fuller is most famous for his 20-story dome housing the U.S. Pavilion at Montreal’s Expo ’67. Later,
he documented the feasibility of a dome two miles in diameter that would enclose mid-town Manhattan in a
temperature-controlled environment, and pay for itself within ten years from the savings of snow-removal
costs alone.
The Cardboard Dome pavillon for the Triennale exhibition in 1954
R. Buckminster Fuller’s first world wide acceptance by the architectural community occurred with the 1954
Triennale where his cardboard dome was displayed for the first time. The Milan Triennale was established to
stage international exhibitions aimed to present the most innovative accomplishments in the fields of design,
crafts, architecture and city planning.
The theme for 1954 was Life Between Artifact and Nature: Design and the Environmental Challenge which fit
in perfectly with Bucky’s work. Bucky had begun efforts towards the development of a Comprehensive
Anticipatory Design Science which he defined as, "the effective application of the principles of science to the
conscious design of our total environment in order to help make the Earth’s finite resources meet the needs
of all humanity without disrupting the ecological processes of the planet." The cardboard shelter that was
part of his exhibit could be easily shipped and assembled with the directions printed right on the cardboard.
The 42-foot paperboard Geodesic was installed in old Sforza garden in Milan and came away with the
highest award, the Gran Premio.
Fuller’s domes gained world wide attention upon his Italian premiere and by that time the U.S. military had
already begun to explore the options of using domes in their military projects because they needed speedy
but strong housing for soldiers overseas. With the interest of the military and coming away from the 1954
Triennale with the Gran Premio, domes began to gain in public appeal and exposure.
Fly eye Dome patent drawings
U.S. Patent Number: 3,197,927 â— Patent Date: August 3, 1965 â— Patent Name: Geodesic Structures â— Complete sphere composed of only two
unique components: 60 triangular convex "dished" faces & 32 transparent bubble skylights
The Flye eye Dome has been patented in 1965.
It is Bucky’s ultimative answer to his lifetime problem to simple shelter construction.
A very few prototypes have been built since then. It is in fact a building system that still needs to
be developed for production in order to be used for serial housing production.
Most Fly eye domes are built with fibreglass modules.
In my opinion Steel is the proper material for Fly eye Domes, as for raw/production costs as for
being easyer tp recycle.
Some advantages of the Fly's Eye dome are:
•
low cost, high strength
•
light weight, easily transported components
•
bolt together assembly
•
lower heating and cooling costs than rectilinear buildings
•
stronger and safer than conventional buildings
•
savings on resources and labor: one third less material is used to enclose
the same space with a dome than a cube.
02
Known built Fly eye Domes
A very little number of Prototypes have been built since the Fly eye structure was
invented. Information and documentation about the single prototypes is rare.
Built during a Workshop in Buckminster Fuller
Institute
InfoPoint in California State USA
John Kuhtik's Fly's Eye Dome see moore @
http://www.thirteen.org/bucky/kuhtikwf.html
Inspiration for artists
The future has arrived! The burgeoning movement toward a
global, nomadic lifestyle is now a reality. Mixing art, architecture,
design and technology, net business, mobile Living,and much more.
03
Ideas for developing the Fly eye Module
In my opinion Steel is the proper material for Fly eye Domes.
According to Fuller’s Idea of the house of the future, home will be more like a spaceship, as we are
too travelling in space, being on a planet.
The Fly eye dome fulfills completevly the concept of a house being a shelter and a medium for
exchange with the outside at the same time.
The most effective production for spaceships on earth is at the moment the car technology,
producing millions of pieces every day for millions of perfectly functioning travelling mashines.
In my opinion Fly eye modules should be built with the same car production tecnology. This would
give to the car production a new marketplace and to the fly eye domes the possibility of being
built, assembling various pieces and making custom production and order easy.
Advantages of steel against Fiberglass Fly eye Modules:
-
Cheaper
-
Easy Industrial production (eg. Car production technology)
-
-
Easy to recycle
Easy industrial customized production
-prototype for steel Fly eye dome
Buckminster Fuller was convinced that you have to see a functioning structure
in order to be certain it is working.
The steel Fly eye dome is, as far as I know, never been built. For this reason it
has to be prototyped and tested before it can be put into mass production.
Many models have been built in various Materials and scale. From 15cm to
1.50m diameter.
-Photoshop modified Image of some models
At the moment I would like to build a 1:1 mid sized Steel pavillon with 7.47 m diamenter.
The complete sphere would take 60 identical modules and 32 round shapes. All modules are
bolted together.
The 747 Dome
The first domes should be built as temporary or permanent installations, in order to get used
to dimensions, weights, costs, timings, improvements, methods….
The size is suitable for a 30sqm x 6m high expositon pavillon, sculpture, playground climber,
greenhouse, futurisctic office, or whatever….
The Dome would be easy anchored to earth bolted to a simple steel/concrete 40cm deep
ringbeam and 10cm slab.