Exploring Geodesic Domes: Architecture Meets Geometry
The concept of a geodesic dome was first coined by Fuller, an important theorist and designer in history, and a rare generalist in the 20th century, who first coined the term geodesic dome and applied for a series of patents, and also widely used this geometric form in architectural design.
In layman's terms, the geodesic dome structure is based on the vertex of the inscribed regular icosahedron of the sphere, dividing the sphere into 20 equal approximately regular triangle surfaces, and then subdividing the sphere with a series of shortest line segments, and finally obtaining a subdivision network that fits the sphere. Geodesic domes can achieve a great span and stability under certain weight restrictions. At the 1967 World Expo, the Montreal Biosphere Pavilion in which Fuller participated used the structure Geodesic Dome. Geodesic domes come in different forms, so let's take a look at them together.
1. Stone dome
The most famous of the stone domes are the Pantheon and Hagia Sophia. Built in 126 AD, 1,800 years ago, the Pantheon was first dedicated to the Roman gods and later became Rome. In the middle of the Pantheon is hollow form, the dome is 43.3 meters in diameter and made of ancient concrete. Its material characteristics are similar to stone, very resistant to pressure, and the dome structure is also mainly under pressure, building materials and structural systems can be described as the sum of heaven, its scale is very large, since its completion 2000 years has been the world's first similar buildings.
Fifteen hundred years ago, the Hagia Sophia was also famous for its huge dome, which is 31.24 meters in diameter and still stands after several major earthquakes.
2. Wooden dome
In addition to stone, wood can also be used to make domes, compared to stone, wood tensile and bending properties are more excellent, such as Schweidler type wooden dome, ribbed ring type wooden dome, but wood is susceptible to moisture, easy to be corroded, nowadays wooden domes are rare.
3. Concrete dome
Concrete is a relatively modern material, and when it comes to concrete domes, the first thing that comes to mind is the small Roman gymnasium in Nelvi. The thin-shell dome of the small Coliseum in Rome was made of 1,620 steel mesh cement precast diamond-shaped grooved slabs poured on the ground formwork, which greatly reduced the cost of construction and created a beautiful ceiling in only seven months.
4. Steel dome
Steel structures are the most used, such as the Reichstag dome and the Izumo dome. The dome of the Reichstag uses a ribbed ring mesh shell, which is more permeable than concrete mesh shell, and is more in line with the definition of modern architecture and the aesthetic standards of modern architecture. The Izumo dome has a diameter of 143.8 meters and a height of 48.9 meters at the top of the arch.
5. Aluminum dome
With the development of social economy, people gradually use aluminum in construction. The density of aluminum is about one-third that of steel, and the strength is about the same as Q235, its corrosion resistance is very strong, maintenance-free, and is a very ideal building material. The shell structure is mainly compressive stress, the construction design is stable control, the node demand is low, and the aluminum alloy structure is especially suitable for geodesic domes dominated by pressure. The well-known Niushoushan Buddha Dome Palace and the skylights of Beijing New Airport are made of aluminum alloy structure.
The above is an introduction to geodesic domes and their structure, have you learned more about them after reading them?