Chinese arch bridges, timber, stone, concrete, steel.

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For Chinese New year, this months summary presentation is on Chinese Arch Bridges; rainbow bridges. Looking at wood and stone traditional structures, it then looks at modern world record long span structures in concrete steel and CFST.

Published in: Design, Technology

Chinese arch bridges, timber, stone, concrete, steel.

  1. 1. 中国的拱桥 China’s Arch Bridges
  2. 2. 中国的拱桥 China’s Arch Bridges Arch bridges have been used for millennia, in China the form has developed and the longest spans can now be found there. This presentation looks at traditional Chinese arch bridges in timber and stone; it then looks at more modern arches in reinforced concrete, Steel and steel-concrete composite (often called CFST). These modern structures, due to their size or location are often as spectacular as the ancient ones.
  3. 3. 木桥 Timber Bridges Rainbow bridges Bridge Building Covered Bridges
  4. 4. A crowded ‘woven timber’ rainbow bridges like this depicted on a 12 th Century scroll, the interlocking timbers allowing the bridge to span further than the length of any one timber.
  5. 5. A modern example of the woven timber. See 1
  6. 6. On those timber bridges that last the rainbow arch effect is lost by the covering which keeps off rain and gives durability. Picture from 1
  7. 7. 石桥 Stone bridges Rainbow or Moon? Open Spandrels Ductility
  8. 8. An old rainbow arch, in China they are more closely symbolized with the moon. A relatively inefficient structural form, can difficult to cross with its very steep spandrels.
  9. 9. The Zhaozhou Bridge, Hebei with its open spandrels and segmental stone arch it looks modern but was built 1400 years ago. For centuries its 37m span was the longest span for such structures. Picture from 1
  10. 10. This stone arch built in 1991 over the Wu-Choahe, Hunan, has a span of 120m. The longest stone span in China is 146m. But such structures lack robustness and fall much more easily than reinforced concrete.
  11. 11. 混凝土桥 Concrete bridges The Longest Cantilevering
  12. 12. Wanxian Bridge, a reinforced concrete bridge over the Yangtze River with a world record concrete span of 420m.
  13. 13. Wanxian Bridge, a concrete bridge built using steel tubes cantilevered out over the river. From ref 2
  14. 14. Cantilever construction From 3
  15. 15. 钢管混凝土拱 Concrete Filled Steel Tube (CFST) Bridges Rainbow bridge Cantilever Efficiency
  16. 16. The Wushan bridge over the Yangtze River, its 460m span was the longest in 2005. Ref 4
  17. 17. Constructing the 530m span Bosideng Bridge over the Yangtze River, again by cantilevering. For a short time a rainbow sculptural form until its completion in 2012.
  18. 18. Structural behaviour of a CFST structure. The composite whole being stronger than the steel alone. From ref 2
  19. 19. 钢桥 Steel Bridges Bird wing efficiency A Western ‘de-optimised’ structure Trussed arch longest span
  20. 20. Lupu Bridge, Shanghai, at 502m the efficient ‘bird wing’ style arch was the longest in the world until 2009. Picture based on Jurgenlison
  21. 21. The Lingtie Bridge a modern 300m span bridge with its inefficient leaning, de-optimised western architecture. From 5
  22. 22. Chaotian Bridge over the Yangtze River, Its 520m trussed span is the longest arch span in the world. From 5
  23. 23. China’s Arch Bridges Wood & Stone Arch bridges have been used for millennia in China. The local carpentry expertise still survives and woven rainbow bridges in timber are still built. The open spandrel stone arch form was developed in China and is still used on large bridges. However, recent failures have highlighted the lack of robustness in some long span designs.
  24. 24. China’s Arch Bridges Steel & Concrete The longest arch span in the world is Chinese, in form it borrows from the Western Steel Trussed Arch. Other borrowings are occurring in wasteful de-optimised architecture, yet there are many exceptions like the elegant bird wing form. The longest span concrete arch in the world is Chinese, it uses a more traditional form. Its construction used steel tubes cantilevered. CFST arches have been shown to be efficient, economic and elegant; a uniquely Chinese solution. The development of this CFST form is still continuing and longer arch spans are likely in the future.
  25. 25. References • Chinese Bridges, RG Knapp & AC Ong, Tuttle, Singapore, 2008. • Steel-Concrete Composite Bridges, D Collings, ICE Publishing, 2013. • Wanxian Long Span Concrete Arch Bridge over Yangtze River, BZ Xie, Symposium Proceedings, 2008. • http://www.highestbridges.com, this has some excellent pictures and text from people who have seen the bridges. • http://en.wikipedia.org/wiki/List_of_longest_arch_bridge_spans, take care this tends to be a bit western orientated, the longest masonry spans are not in France!
  26. 26. …making the complex simple… David Collings 大衛 http://www.slideshare.net/DavidCollings/david-collings-bsc-ceng-fice-personal-careerdc-summary
  27. 27. Teaching David has lectured on the University of Surrey’s MSc course in steel concrete composite bridges, and a visiting lecturer at Imperial College, London. David is a Supervising Civil Engineer for the ICE training scheme, he has seen many successfully pass their Professional Review and gain the prestigious MICE qualification. During his time in SE Asia David learnt to read, write and speak Chinese ( 汉语 ), continuing to learn as well as teach. . David also carries out bespoke lectures for company CPD requirements, recent lectures include; Extradosed Bridges, Concrete Diaphragm Design, Design of steel-concrete composite bridges, etc. Extracts or summaries of some presentations are available for free download on slideshare.com: http://www.slideshare.net/DavidCollings/steel-concrete-composite-bridges http://www.slideshare.net/DavidCollings/extradosed-bridges-exploring-the-boundaries
  28. 28. Presentation by CRD and Wolf productions.

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