Historically, the term counter-arch was used in architecture to describe multiple types of arches that provide opposing action:[1][2]
![](https://upload.wikimedia.org/wikipedia/commons/thumb/1/12/Diagram_of_Moseley_bridge_design.png/220px-Diagram_of_Moseley_bridge_design.png)
- an inverted arch used opposite of a regular one. For example, an inverted arch in an open spandrel or in "Moseley bridges", a popular American Civil War-era design by Thomas William Moseley, where the counter-arches were intended as a low-cost alternative to diagonal bracing;[3]
- any relieving arch;
- outer "rings" of arches overlaying the one forming the intrados, used in old English bridges since medieval times, are called "counter-arches"[4] following the works of John Smeaton;
- an arch that is built adjacent to another arch to oppose its forces or help stabilize it.[5] The counter-arch can be used, for example, when constructing the flying buttress,[6]
- buttressing arches built between the opposing building facades over narrow streets of old cities;[7][8]
- in fortification, an arch built on the tops of counterforts behind the bastion walls intended to limit the scope of the potential wall breaching;[9]
- when a pier of the Old Westminster Bridge started sinking during the construction, Charles Labelye was forced to retrofit the bridge with open spandrels using the counter-arches springing off haunches of the two adjacent arches of the bridge thus relieving the pier.[10]
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An old Ouse Bridge, York with middle arch using three rings (two "counter-arches")[11]
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Buttressing counter-arches in Bonifacio, Corsica
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Counter-arched wall of a bastion (the voids are usually filled)
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Old Westminster Bridge, with open spandrel
See also
[edit]References
[edit]- ^ Murray 1893, p. 1061.
- ^ Hodgson 1996, p. 289.
- ^ Trautwine 1874, p. 289, Moseley Bridge.
- ^ Ruddock 1979, p. 81.
- ^ "counter arch." McGraw-Hill Dictionary of Architecture and Construction. McGraw-Hill Companies, Inc., 2003. Answers.com, 7 September 2008.
- ^ Curl 2006, p. 207.
- ^ Niglio & Ulivieri 2018, p. 21.
- ^ Lima et al. 2015, p. 238.
- ^ Royal Military College 1852, p. 46.
- ^ Ruddock 2017, p. 165.
- ^ Ruddock 1979, p. 85.
- ^ Derwig, Jan. "Ijburg Bridge 1 Amsterdam, Netherlands". grimshaw.global. Retrieved 8 November 2021.
Sources
[edit]- Curl, James Stevens (2006). "counter-arch". A Dictionary of Architecture and Landscape Architecture (2nd ed.). Oxford University Press. ISBN 978-0-19-860678-9. Retrieved 2024-01-03.
- Murray, J.A.H. (1893). "Counter-arch". A New English Dictionary on Historical Principles: part 1. C-Comm (1893). Clarendon Press. Retrieved 2024-07-05.
- Trautwine, J.C. (1874). "The Moseley Bridge". The Civil Engineer's Pocket-book: Of Mensuration, Trigonometry, Surveying, Hydraulics ... Etc. ... Claxton, Remsen & Haffelfinger. Retrieved 2024-07-05.
- Hodgson, John A. (1996). The Behaviour of Skewed Masonry Arch Bridges (PDF) (PhD thesis). University of Salford.
- Ruddock, T. (1979). Arch Bridges and Their Builders 1735-1835. Cambridge University Press. ISBN 978-0-521-21816-0. Retrieved 2024-07-05.
- Niglio, Olimpia; Ulivieri, Denise (2018). "Vernacular architecture and "historical seismography": an experience research" (PDF). Structural Analysis of Historical Constructions - 2 Volume Set: Possibilities of Numerical and Experimental Techniques - Proceedings of the IVth Int. Seminar on Structural Analysis of Historical Constructions, 10-13 November 2004, Padova, Italy. CRC Press. ISBN 978-0-429-62100-0. Retrieved 2024-07-05.
- Lima, A; Correia, M; Gomes, F; Carlos, G; Viana, D; Lourenço, P; Varum, H (2015-09-08). "Systematisation of seismic retrofitting in vernacular architecture". Seismic Retrofitting: Learning from Vernacular Architecture. CRC Press. pp. 235–239. doi:10.1201/b18856-49. ISBN 978-1-138-02892-0.
- Royal Military College, Sandhurst (1852). Outlines of a Course of Lectures on Fortification, Military Tactics, and Perspective: With the Attack and Defence of Fortresses. Spottiswoodes and Shaw. Retrieved 2024-07-05.
- Ruddock, E.C. (2017). "Hollow Spandrels in Arch Bridges". Masonry Bridges, Viaducts and Aqueducts. Studies in the History of Civil Engineering. Taylor & Francis. ISBN 978-1-351-91928-9. Retrieved 2024-07-06.
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