Saturday, February 23, 2019


The RanDome

Buckminster Fuller is well known for his determined effort to address the global shelter shortage by using his concept of Comprehensive Anticipatory Design Science. Design science strategy focuses on using the world's resources to the greatest advantage possible. One measure of a dwelling's success is its performance per kilogram of material. By increasing a material's performance through design, and thus the efficacy and efficiency of both the cost and labor of construction, the possibility for sheltering all the world's population will also increase.
Fuller made great progress in his efforts to address the problems of shelter. The geodesic dome is a milestone in the history of shelter. The RanDome is an advancement in building design that will take Fuller's geodesic shells to new levels of functionality and versatility. The RanDome is a new kind of geodesic shell which is far simpler than existing space enclosing building strategies. RanDomes are mass-produced and assembled from a variety of materials. RanDomes are inexpensive, strong, long lasting and weatherproof - exactly the type of structure to address the global problem of inadequate shelter.
The RanDome achieves these benefits by changing, fundamentally, how we view the basic building element. The RanDome structure is not an assemblage of edges and faces, as are traditional shell structures. It is assembled from a number of overlapping cones called vertex elements. A RanDome has all the structural benefits of a traditional geodesic shell structure but without the complexity of design, manufacture and construction. The RanDome construction strategy is intuitive. It is a Trimtab improvement on mass shelter construction by virtue of elegant simplicity. This building strategy needs no advanced educational degrees or construction experience. It transcends literacy, language and cultural barriers. Everyone, even children, can now build a sturdy, weatherproof and healthy shelter.
A RanDome intended for human shelter is assembled from numerous identical vertex elements. Vertex elements are cones. A cone is fabricated from a sheet of material. We use a typical sheet in the shape of a circle, square or rectangle, whose maximum dimension is usually one meter. The semi-rigid sheet material can be any kind available. The preferred material is weather-, insect-, rot- and fire- resistant. Examples of suitable materials are metal, corrugated plastic, plywood, cardboard, fiberboard, fiberglass, or similar products.
That all vertex elements are identical leads directly to manufacturing efficiency. When one is fabricating a large number of identical elements, the economies of scale and ease of process are best taken advantage of.
This is a construction method previously unknown and unexploited. Some basic mathematics can be used to explain our unique approach. Until now builders have assembled their structures using only two of the three topological features. Leonard Euler discovered 257 years ago that all polyhedrons can be reduced no further than into edges, faces and vertexes. For example, a cube has 8 vertexes, 6 faces and 12 edges. People build shelters using face elements or edge elements. People do not yet build shelters using vertex elements. The basic building component of a RanDome is a vertex element and this makes all the difference.
Cones are simple to calculate and easy to fabricate. The fabrication begins with a flat sheet of building material. An angle is made in the shape of a narrow triangle from the center to the perimeter of the sheet. The sheet is then cut and lapped, or folded without cutting, according to this angle, to create a vertex, thus producing a cone element. The angle of this lap or fold is determined using simple mathematics. The relationship of the individual angle in degrees to the whole structure is 720/n, where n is the number of cone elements employed. For example, if 100 sheets are used for a half-sphere structure, the required angle is 360 degrees divided by 100 pieces, or 3.6 degrees per angle.
The cones can be mass produced and stacked efficiently for shipping. They are assembled on-site, or pre-assembled before deployment, by anyone using a technique similar to shingling a roof. The elements are overlapped just as one would overlap shingles on a traditional roof. The upper element extends outside and over top of the lower element. Rain water is forced to shed onto the ground. Leaks are virtually impossible. Elements are attached to each other with common fasteners such as nuts and bolts or rivets. Double adhesive tape, magnets or clamps hold the elements in place during this fastening process. Each fastener is made weather tight. Erection of the shell structure can proceed from the top to the bottom or the reverse. Top down erection is preferred, raising the structure during the process of erection, to allow all work to take place at ground level. Doors, windows and vents are installed in the traditional manner, adding frames where needed.
One of the fascinating and beautiful aspects of the RanDome is that the placement or arrangement of the structure's elements during erection is done in an approximately random fashion. No precise measurements are required. Elements are overlapped and fastened together with a predetermined average distance between cone vertexes. A 50% overlap of the cone elements is typical. In climates with heavy snow and wind loads expected, or when the available sheet material is relatively thin, overlap will be maximized to strengthen the shell. Double and triple layers of elements are desirable depending on the expected function of the shell structure. This layering makes possible very strong domes using very thin sheet material. In extreme climates, either very hot or very cold, two or three concentric shells with an air space between the shells will be useful. For added strength, these shells can be bridged with short connectors such that one shell supports the other. Finally, with slightly more complexity, any shape RanDome is possible just by varying the cone angle of the elements of a particular structure.
Richard Fischbeck
18 Belfast Rd
Freedom, ME