Biogas Dome Construction Using Pneumatics
Main Article Content
Abstract
Fixed spherical dome biogas reactors are popular in Nepal for the production of biogas from waste materials. Current practice uses heaped soil as temporary formwork for an unreinforced concrete dome. This paper explores the structural requirements of biogas domes and presents a potential alternative construction process using air-supported flexible formwork that would be suitable for use in Nepal. A prototype dome was created to assess the feasibility of the formwork system. Load testing of the dome was undertaken to confirm structural performance. The results show that an air supported formwork system would be feasible for use in biogas domes with the formwork fabricated easily on site with only basic materials and fixings.
Article Details
This work is licensed under a Creative Commons Attribution 4.0 International License.
References
Araya, R. and West, M. (2012). Flat sheet fabric moulds for double curvature precast concrete elements. Proceedings of the Second International Conference on Flexible Formwork. University of Bath, Bath, 27–29 June 2012.
Arfken, G. (1985). Spherical polar coordinates. Mathematical methods for physicists, 3rd Ed. Orlando, FL: Academic Press.
Bini, D. (1967). A new pneumatic technique for the construction of thin shells. Proceedings from the 1st IASS International Colloquium on Pneumatic Structures. University of Stuttgart, Germany, 11–12 May 1967.
Bini, D. (1974). Concrete domes. Official Journal of the Masters Builders' Association of New South Wales, 3(7): 326–334. Bostik. (2016). Soft plastics adhesive. Stafford, England: Bostik.
British Standards Institute (BSI). (2009). BS EN 12350: Testing fresh concrete. London: BSI.
Devkota, G.P. (2001). Biogas technology In Nepal: A sustainable source of energy for rural people. Kathmandu: B Devkota.
Dulácska, E. (1985). Buckling analysis of reinforced concrete shells. Proceedings of Inelastic Behaviour of Plates and Shells, IUTAM Symposium. Rio de Janeiro, Brazil, 5–9 August 1985.
Food and Agriculture Organization (FAO). (2011). World livestock 2011 – Livestock in food security. Rome: FAO.
Fulford, D.J. (2015). Small scale rural biogas programmes. Rugby, Warwickshire, UK: Practical Action Publishing. https://doi.org/10.3362/9781780448497
Hamed, E., Bradford, M.A. and Gilbert, R.I. (2010). Nonlinear long-term behaviour of spherical shallow thin-walled concrete shells of revolution. International Journal of Solids and Structures, 47(2): 204–215. https://doi.org/10.1016/j.ijsolstr.2009.09.027
Harris, J.W. and Stocker, H. (1998). Spherical segment (spherical cap). Handbook of mathematics and computational science. New York: Springer-Verlag.
Heifetz, H. (1972). Inflatable forms. U.S. Pat. 3,643,910. Isler, H. (1979). New materials for shell and spatial structures. Proceedings of IASS world conference. Madrid.
Kenaway, M. (2014). A proposed segmented precast concrete spherical cap: Geometry, structural stability and construction. MSc. diss., The American University in Cairo.
Kollegger, J., Kromoser, B. and Dallinger, S. (2012). The building of ice and concrete shells by employing pneumatic formwork. Proceedings of Second International Conference on Flexible Formwork. Bath, University of Bath, 27–29 June 2012.
Krenzke, M.A. and Kiernan, T.J. (1965). The effect of initial imperfections on the collapse strength of deep spherical shells, David Taylor Model Basin Report 1757. Washington, USA: Department of the Navy. https://doi.org/10.21236/AD0612100
Kromoser, B. and Huber, P. (2016). Pneumatic formwork systems in structural engineering. Advances in Materials Science and Engineering. https://doi.org/10.1155/2016/4724036
Kromoser, B. and Kollegger, J. (2014). Herstellung von Schalentragwerken aus Beton mit der "Pneumatic Wedge Method" – Ein neues Bauverfahren für den Bau von zweifach gekrümmten Betonflächen (Production of shell structures made of concrete with the "Pneumatic Wedge Method" – A new construction method for the construction of double-curved concrete surfaces). Betonund Stahlbetonbau, 109(8): 557–565. https://doi.org/10.1002/best.201400014
Monolithic. (2014). The monolithic dome. Available at: http://www.monolithic.org/topics/domes [Accessed on 15 September 2016]. Neff, W. (1941a). Building construction. U.S. Pat. 2,270,229.
Neff, W. (1941b). Improved method of erecting shell-form concrete structures. USA patent application 2,892,239.
Nose, T. (1926). Process of constructing culverts of pipes of concrete. U.S. Pat. 1,600,353.
PIRS SAS. (2014). Dome construction. Available at: http://www.domepirs.com/en/welcome [Accessed on 15 September 2016].
Roessler, S. and Bini, D. (1986). The Binishell system – Thin shell concrete domes. Concrete International, 8(1): 49–53.
Schlaich, J. and Sobek, W. (1986). Suitable shell shapes. Concrete International, January(1986): 41–45.
Seaman, L. (1962). The nature of buckling in thin spherical shells. PhD diss., Massachusetts Insitute of Technology.
Sobek, W. (1986). Concrete shells constructed on pneumatic formwork. Proceedings of IASS Symposium on Membrane Structures and Space Frames. Osaka, Japan, 15–19 September 1986.
Sobek, W. (1987). Auf pneumatisch gestützten Schalungen hergestellte Betonschalen (Pneumatically assisted formwork for concrete shells). Stuttgart: Verlag Ursula Sobek.
South, D. B. (1990). Economics and thin shell dome. Concrete International Magazine, 12(8): 24–29.
Tang, G. (2015). An overview of historical and contemporary concrete shells, their construction and factors in their general disappearance. International Journal of Space Structures, 30(1): 1–12. https://doi.org/10.1260/0266-3511.30.1.1
Tang, G. and Pedreschi, R. (2015). Deployable gridshells as formwork for concrete shells. Proceeding of IASS ISOFF. Amsterdam, 16–17 August 2015.
Timoshenko, S. and Woinowsky-Krieger, S. (1959). Theory of plates and shells. New York: McGraw-Hill.
Veenendaal, D., West, M. and Block, P. (2011). History and overview of fabric formwork: Using fabrics for concrete casting. Structural Concrete, 12(3): 164– 177. https://doi.org/10.1002/suco.201100014
Volmir, A. (1963). Stability of elastic systems. Mosow: Fizmatgiz.
Von Karman, T. and Tsien, H.S. (1939). The buckling of spherical shells by external pressure. Journal of the Aeronautical Sciences, 7(2): 43–50. https://doi.org/10.2514/8.1019
West, M. (2007). CAST construction. Winnipeg, Manitoba, Canada: University of Manitoba.
West, M. (2013). Fabric-formed precast panels – Simple, economical, formwork for natural forms and structurally efficiency. Facade Tectonics Journal: Precast Concrete, 1(1): 93–100.
West, M. and Araya, R. (2009). Fabric formwork for concrete structures and architecture. Proceedings of International Conference on Textile Composites and Inflatable Structures, Structural Membranes. Stuttgart, Germany, 5–7 October 2009.
YSM Ltd. (2014). DOMECRETE building system. Available at: http://ysmforbuilding.com/en/domecrete-domes-building-system [Accessed on 15 September 2016].
Zoelly, R. (1915). Uber ein Knickungsproblem an der Kugelschale (On the problem of buckling of the spherical shell). PhD diss., ETH Zurich. https://doi.org/10.3929/ethz-a-000091951