Geodesic dome A geodesic dome is a hemispherical thin-shell structure (lattice-shell) based on a geodesic polyhedron. The triangular elements of the dome are structurally rigid and distribute the structural stress throughout the structure, making geodesic domes able to withstand very heavy loads for their size. Contents History Methods of construction Dome homes Disadvantages Related patterns Largest geodesic dome structures The Montreal Biosphère, formerly the American Pavilion of Expo 67, by R. Buckminster Fuller, on Île See also Sainte-Hélène, Montreal, Quebec References External links History The first geodesic dome was designed after World War I by Walther Bauersfeld,[1] chief engineer of the Carl Zeiss optical company, for a planetarium to house his planetarium projector. A first, small dome was patented, constructed by the firm of Dykerhoff and Wydmann on the roof of the Zeiss plant in Jena, Germany. A larger dome, called "The Wonder of Jena", opened to the public in July 1926.[2] Twenty years later, Buckminster Fuller coined the term "geodesic" from field experiments with artist Kenneth Snelson at Black Mountain College in 1948 and 1949. Although Fuller was not the original inventor, he is credited with the U.S. popularization of the idea for which he received U.S. Patent 2682235A (https://patents.google.com/patent/US2682235A) on 29 Spaceship Earth at Epcot. June 1954.[3] The oldest surviving dome built by Fuller himself is located in Woods Hole, Massachusetts, and was built by students under his tutelage over three weeks in 1953.[4] 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. The dome was successfully adopted for specialized uses, such as the 21 Distant Early Warning Line domes built in Canada in 1956,[5] the 1958 Union Tank Car Company dome near Baton Rouge, Louisiana, designed by Thomas C. Howard of Synergetics, Inc. and specialty buildings such as the Kaiser Aluminum domes (constructed in numerous locations across the US, e.g., Virginia Beach, Virginia), auditoriums, weather observatories, and storage facilities. The The Climatron greenhouse at dome was soon breaking records for covered surface, enclosed volume, and construction speed. Missouri Botanical Gardens, built in 1960 and designed by Beginning in 1954, the U.S. Marines experimented with helicopter-deliverable geodesic Thomas C. Howard of domes. A 30-foot wood and plastic geodesic dome was lifted and carried by helicopter at 50 Synergetics, Inc., inspired the knots without damage, leading to the manufacture of a standard magnesium dome by domes in the science fiction Magnesium Products of Milwaukee. Tests included assembly practices in which previously movie Silent Running untrained Marines were able to assemble a 30-foot magnesium dome in 135 minutes, helicopter lifts off aircraft carriers, and a durability test in which an anchored dome successfully withstood without damage, a day-long 120 mph (190 km/h) propeller blast from the twin 3,000 horsepower engines of an anchored airplane.[6] The 1958 Gold Dome in Oklahoma City, Oklahoma, utilized Fuller's design for use as a bank building. Another early example was the Stepan Center at the University of Notre Dame, built in 1962.[7] The dome was introduced to a wider audience as a pavilion for the 1964 World's Fair in New York City designed by Thomas C. Howard of Synergetics, Inc. This dome is now used as an aviary by the Queens Zoo in Flushing Meadows Corona Park after it was redesigned by TC Howard of Synergetics, Inc. Another dome is from Expo 67 at the Montreal World's Fair, where it was part of the Science World in Vancouver, American Pavilion. The structure's covering later burned, but the structure itself still stands built for Expo 86, and inspired and, under the name Biosphère, currently houses an interpretive museum about the Saint by Buckminster Fuller's Lawrence River. Geodesic dome. In the 1970s, Zomeworks licensed plans for structures based on other geometric solids, such as the Johnson solids, Archimedean solids, and Catalan solids.[8] These structures may have some faces that are not triangular, being squares or other polygons. In 1975, a dome was constructed at the South Pole, where its resistance to snow and wind loads is important. On October 1, 1982, one of the most famous geodesic domes, Spaceship Earth at Epcot in Walt Disney World Resort in Bay Lake, Florida, just outside of Orlando opened. The building and the ride inside of it are named with one of Buckminster Fuller's famous terms, Spaceship Earth, a world view expressing concern over the use of limited resources available on Earth and encouraging everyone on it to act as a harmonious crew working toward the greater good. The building is Epcot's icon, representing the entire park. For the 1986 World's Fair (Expo 86), a Buckminster Fuller inspired Geodesic dome was designed by the Expo's chief architect Bruno Freschi to serve as the fair's Expo Centre. Construction began in 1984 and was completed by early 1985. The dome and the building now serve as an Arts, Science and Technology center, and has been named Science World.[9] In 2000, the world's first fully sustainable geodesic dome hotel, EcoCamp Patagonia, was built in Chilean Patagonia,[10] opening the following year in 2001. The hotel's dome design is key to resisting the region's strong winds and is based on the dwellings of the indigenous Kaweskar people. Geodomes are also becoming popular as a glamping (glamorous camping) unit. Methods of construction 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. With this method, the struts may be cut to the exact length needed. Triangles of exterior plywood are then nailed to the struts. The dome is wrapped from the bottom to the top with several stapled layers of tar paper, to shed water, and finished with shingles. This type of dome is often called a hub-and-strut dome because of the use of steel hubs to tie the struts together. Paneled domes are constructed of separately framed timbers covered in plywood. The three members comprising the triangular frame are often cut at compound angles to provide for a flat fitting of the various triangles. Holes are drilled through the members at precise locations Long Island Green Dome and steel bolts then connect the triangles to form the dome. These members are often 2x4s or 2x6s, which allow for more insulation to fit within the triangle. The panelized technique allows the builder to attach the plywood skin to the triangles while safely working on the ground or in a comfortable shop out of the weather. This method does not require expensive steel hubs. Temporary greenhouse domes “Magidomes” can be constructed by stapling plastic sheeting onto a dome constructed from common lumber. The result is warm, movable by hand and affordable. It should be staked to the ground to prevent it being moved by wind. Steel framework can be easily constructed of electrical conduit. One flattens the end of a strut and drills bolt holes at the needed length. A single bolt secures a vertex of struts. The nuts are usually set with removable locking compound, or if the dome is portable, have a castellated nut with a cotter pin. This is the standard way to construct domes for jungle gyms. Domes can also be constructed with a lightweight aluminium framework which can either be bolted or welded together or can be connected with a more flexible nodal point/hub connection. These domes are usually clad with glass which is held in place with a PVC coping. The coping can be sealed with silicone to make it water tight. Some designs also allow for double glazing or insulated panels to be fixed in the framework. This allows a fully habitable building to be formed. Concrete and foam-plastic domes generally start with a steel framework dome, wrapped with chicken wire and wire screen for reinforcement. The chicken wire and screen are tied to the framework with wire ties. A coat of material is then sprayed or molded onto the frame. Tests should be performed with small squares to achieve the correct consistency of concrete or plastic. Generally, several coats are necessary on the inside and outside. The last step is to saturate concrete or polyester domes with a thin layer of epoxy compound to shed water. Some concrete domes have been constructed from prefabricated, prestressed, steel-reinforced concrete panels that can be bolted into place. The bolts are within raised receptacles covered with little concrete caps to shed water. The triangles overlap to shed water. The triangles in this method can be molded in forms patterned in sand with wooden patterns, but the concrete triangles are usually so heavy that they must be placed with a crane. This construction is well-suited to domes because no place allows water to pool on the concrete and leak through. The metal fasteners, joints, and internal steel frames remain dry, preventing frost and corrosion damage. The concrete resists sun and weathering. Some form of internal flashing or caulking must be placed over the joints to prevent drafts. The 1963 Cinerama Dome was built from precast concrete hexagons and pentagons. Domes can now be printed at high speeds using very large, mobile "3D Printers", also known as additive manufacturing machines. The material used as the filament is often a form of air injected concrete or closed-cell plastic foam.