Akademik

   The dome, which is created from an arch turned on its axis 360 degrees, is traditionally considered one of the most important Ancient Roman architectural inventions. Although round temples were not new to Ancient Rome, the Pantheon, when it was built in AD 120, was unprecedented in its scale. Both the diameter and height of the dome measure 143 feet, and it features a 30-foot-wide round oculus window in its center. Made of a volcanic rock called tufa, considered an early form of concrete, the dome also features coffering, a series of squares cut out of the concrete to reduce its weight and provide a sense of rhythm and order to the dome's interior. The 20-foot-thick walls are not solid, but built up of concrete layered with arches to relieve the tremendous weight of the dome through the walls. Despite the prevalence of domed structures in Ancient Rome, most Roman buildings used a stone or wood vaulting system rather than a dome. Domes constructed through the Middle Ages were smaller and built of masonry with ribbing. Following the same design principles as the pointed arch, they feature a pointed top capped by a pinnacle.

   The structural knowledge of the Ancient Roman semispherical dome was lost over time, not to be rediscovered until the Renaissance. Until the early 1400s, the dome of the Florence Cathedral and its octagonal drum remained open, given the overly ambitious plan of earlier architects to construct the largest building in all of Italy. In 1417, Filippo Brunelleschi was hired to complete the dome. He had just returned from Rome, where his studies of Ancient Roman architecture involved the careful measuring of specific buildings, including the Pantheon. Because of the preexisting octagonal drum, Brunelleschi was not able to build a round dome like the Pantheon, so instead he designed a modified solution that involved a double-shelled dome with ribs set into the corners of the drum and a slightly pointed top, capped by a lantern. This dome was the first since antiquity to employ ancient methods of construction and was therefore hailed as the first "true" Renaissance building. Through the Renaissance, domes of all sizes were constructed, meant to recall the grandeur of Ancient Rome. In the 1560s, Andrea Palladio introduced the dome in a domestic building, as seen in his Villa Rotonda, built outside Vicenza. Thus, Palladio reintroduced in this rural home for his upper-class patron both the ancient villa and the idea of the imperial domus (of the word "domestic").

   Domes became an almost mandatory feature of subsequent Renaissance and then Baroque churches, including Saint Peter's Church in Rome, begun in 1505 and completed in the early 1600s. But the domestic dome never became very popular outside of a number of Neo-Classical homes from the 18th century, such as Richard Boyle's Chiswick House, built in West London in the 1720s, and Thomas Jefferson's Monticello, built in Charlottesville, Virginia, beginning in the 1770s. By the 19th century, domes became increasingly important features of most government buildings constructed in the United States, in emulation of the original domed United States Capitol, Washington, D.C., begun in 1803 by Benjamin Henry Latrobe. The most recent state capitol to receive a classical dome is in Oklahoma City, where the capitol dome was planned in 1914 but not completed until 1997.

   While these domes all retain a historical referencing in their classical designs, new dome possibilities began to appear in the 20th century, as architects explored new ways of manipulating reinforced concrete in their domes. Pier Luigi Nervi's Palazzetto dello Sport, built in Rome for the 1960 Olympics, is a good example of his combination of engineering and aesthetics to create a thin concrete shell dome that spans a huge interior. These thin-shelled, organic-styled concrete roof coverings were more recently the source of inspiration for the Millennium Dome, a massive structure supported by masts that look like giant stakes driven through the top of the dome. Built in southeast London by Richard Rogers and the structural engineer Buro Happold for the year-long millennium celebrations held there in 2000, this building is currently an indoor sports arena.

   Finally, the geodesic dome, another modern innovation, is a highly technical structure whereby a reinforced dome is created with intersecting lines. Although it is made from linear elements, it is ultimately a spherical structure created from a network of struts arranged around intersecting circles that lie on the surface of the sphere. Triangles are formed where the circles intersect and disperse the stress more evenly across the surface. This innovation is the sole man-made structure that can become stronger as it gets larger. Geodesic domes are mathematically complex, whereby a shape such as an icosahedron (a polyhedron with 20 faces, usually with equilateral triangles in each face) is used to measure out a pattern of triangles lying with minimal distortion on the surface of the sphere. The edges of the triangle are called geodesics. Although a variety of patterns can be used to create geodesic domes, the expense of creating a new pattern has standardized the dome into a few prevalent shapes.

   The geodesic dome was built by Walther Bauersfeld in 1922 as a planetarium in Germany, but it was first introduced to the broader public at the American Pavilion of Expo '67 held in Montreal. Created by R. Buckminster Fuller, the American Pavilion dome was based on mathematical studies performed at Black Mountain College in Asheville, North Carolina, in the 1940s. Several Bauhaus architects, including Walter Gropius, taught at Black Mountain during this same decade, and from that point on, Fuller, an inventor, poet, and visionary, began to dedicate his work toward developing a utopian vision of improving human existence through more economical automobiles and homes. Fuller hoped that this strong, light-weight structure could be used for inexpensive housing, an idea that he developed further in his Dymaxion House, from 1945. This round home is made of metal covered in polished aluminum and resembles a flattened dome. The entire house is so lightweight that it can rotate around a central mast to improve air circulation. It also had other economical features, including rotating drawers and a finemist shower. Although this widely popular prototype of a home was never produced, a model can be found today in the Henry Ford Museum in Dearborn, Michigan. Domes, particularly the lightweight geodesic domes, continue to be modified for use in architectural construction today.