Triodetic dome explained

A Triodetic dome is a type of geodesic dome whose space frame is constructed using Triodetic connectors, invented in 1955 by the Canadian Arthur E. Fentiman.^{[1] [2]}

History

Triodetic connectors were invented in 1955 by the Canadian Arthur E. Fentiman (1918–93), and patented in 1958. The system was developed further by A. E. Fentiman's brother, Harold Gordon ("Bud") Fentiman (1921–86) and was in commercial use by 1960.^[3] Triodetic Structures Ltd was established in 1962 to market the system; the Fentiman family sold the company in 1977.

Description

The connector consists of a hub, usually of aluminium, with up to twelve slots into which tubes (the axial members) can be inserted. The assemblage is stabilized by a central bolt with a washer (through the middle of the hub). It is generally used with aluminium tubes, but stainless steel was introduced in 1966.^[4] The tubes do not require bolting or welding together,^[5] and the frame can be put together by non-specialists using basic equipment.

Various shapes in addition to domes are possible, including barrel vaults, pyramids and hyperbolic paraboloids. Recent applications of the system have included as foundations for building, which can function on permafrost.^[6]

Examples of Triodetic structures

Canada

• Netherlands pavilion at Expo 67, Montreal, designed by Walter Eykelenboom (1967)
• Bloedel Floral Conservatory, Vancouver, British Columbia (1968)^[7]
• Rainbow Stage, Winnipeg, Manitoba (1970)^[8]
• Cinesphere, Toronto, Ontario (1971)^[9]
• Research hut on Mount Logan, Yukon (1977)^[10]
• Metro Toronto Zoo pavilions (1972)^[11]
• Niagara Falls Marineland (1974)
• Royal Tyrrell Museum greenhouse, Drumheller, Alberta (1985)
• Holy Trinity Greek Orthodox Church, London, Ontario (2000)

United States

• Pavilion of John Fitzgerald Kennedy Library, Boston, designed by I. M. Pei (1979)
• Turtle Dome (Strongheart Recreation Center), Grand Traverse, Michigan (c. 2001)
• Liberace Museum extension, Las Vegas (2002)
• The Strong National Museum of Play extension, Rochester, New York (2006)^[12]

Elsewhere

• Roman Catholic Church of St Joseph, Wool, Dorset, England (1969–71)^[13]
• Royal Botanic Garden plant house, Sydney, Australia (1974)
• Arts Centre Melbourne spire, designed by Roy Grounds (1980)
• Blue Mosque, Shah Alam, Malaysia (1988)
• Airport terminal, Havana, Cuba (1995)
• Canadian embassy, Cairo (2002)

See also

• Gridshell
• Shell (structure)
• Truss

Notes and References

1. Maria Cook (13 July 2003). The Buckminster Fuller of Kanata. The Ottawa Citizen, p. C3
2. M. Y. H. Bangash, T. Bangash. Tension Structures. In: Elements of Spatial Structures – Analysis and Design, pp. 389–484 (Thomas Telford Publishing; 2003)
3. Z. S. Makowski (1993). Space structures – a review of the developments within the last decade. In: Space Structures 4: Proceedings of the Fourth International Conference on Space Structures, pp. 1–8 (G. A. R. Parke, C. M. Howard, eds)
4. G. S. Ramaswamy, Mick Eekhout, G. R. Suresh. Introduction to space frames. In: Analysis, Design and Construction of Steel Space Frames, pp. 11–13 (Thomas Telford; 2002)
5. New Products at the Building Exhibition. The British Aluminium Company, Ltd. Official Architecture and Planning 26 (11): 1163 (1963)
6. Charly Ligety (2021). A Fresh Look at Emergency and Rapid Shelter Solutions. Cityscape 23 (2): 459–72
7. John Mitchell (4 May 2002). Vancouver blooms; Tropicial [sic] plants and birds flourish at Bloedel Floral Conservatory. Toronto Star, p. K18
8. Glen Harrison (2015) [2013]. Rainbow Stage, The Canadian Encyclopedia
9. Ontario Place. The Canadian Architect 62 (5): 68 (2017)
10. G. Holdsworth (1979). Installation of a Dome Shelter on Mount Logan Yukon Territory. Arctic 32 (1): 33–41
11. Beth Kapusta, John McMinn (2001). Engineering Canadian Modernism. The Canadian Architect 46 (4): 10–13
12. Unique structure. Daily Commercial News and Construction Record79 (140): 2 (2006)
13. https://historicengland.org.uk/listing/the-list/list-entry/1416504?section=official-list-entry Roman Catholic Church of St Joseph