Recently in Architecture, we’ve been studying prefabricated Architecture. This is when the supplies and building materials are first made (normally in factories), then shipped to the construction site where they are assembled into the building.
We were looking at a specific part of these buildings however. My professor chose buildings that all have very interesting types of joints used in the construction of these buildings.
The building I was assigned was the Montreal Biosphere. It was designed by American architect Buckminster “Bucky” Fuller for the Expo 67 in Montreal. The building is a large geodesic dome built around a little museum designed to display American culture. In this blog, we’ll discuss the architect, the building, the concept behind a geodesic dome and the joint used in this building.
Let’s start off with the architect. He had a rather tough road to success. Buckminster Fuller was expelled from Harvard twice, once for partying, and the second time for having “bad ideas”. That wasn’t it. When he was 32, he hit a serious road block. 5 years prior, his daughter died at the age of 4. Now, he just lost his job as president of a company who specialized in structures. On top of that him and his wife just had a newborn baby. They had no way to pay their bills and we’re going into debt. He was also becoming a serious drinker. One night, on his usual walk around Chicago where they lived, he walked next to Lake Michigan, and considered drowning himself. He thought his family would be better off with the insurance money. But instead a voice told him he can’t. It told him that he has no right to kill himself. And that if he were to use the skills that he has for the right reasons, then he will find out that he has a purpose on this planet. From that day on he was one of the great pioneers and scientists looking into the integrity of certain structures, trying to find the most efficient ones.
The building is a unique one to say the least. It has the dome on the outside and then the building on the inside. The geodesic dome is made out of steel, specifically the struts on the dome are made of 3 inch steel tubes. The size and weight of the material diminishes towards the top in an effort to help the building stand. Also, if you look closely, it can be seen that the building actually has two spheres concentric to one another, the inner sphere helps with the structural integrity of the building.
The next thing is some information on geodesic domes. They are very useful for designers and architects because they have the smallest surface area (material usage) for the largest volume (space). It’s cost efficient in that sense. It’s said that a house made of a geodesic dome uses 1/3 the amount of lumber to build compared to a normal house. So the way it works is that a geodesic dome is made of equilateral triangles that transfer the load of the dome throughout the structure. It can have 4, 6, 8, 12, or 20 faces. The Montreal Biosphere is a 20-sided (icosahedron) dome. This may have you thinking, “Well I see so many more!” but it’s technically 20 sides and then a repetition of equilateral triangles in each face to give it a more spherical shape.
The last thing is the joint. The system of jointing in the dome is a hub and strut system. Basically there’s a hub, which is like the center, and then struts run out from them and to other hubs. The hubs on the building are a hexagonal shape with arms that extend out to which the pipes can attach to. The struts are the 3 inch steel tubes that I mentioned before. There is little documentation so it required just photographs, mostly poor ones, and diagrams/logic to map out how the joint works and what it looks like.