The presentation provides a summary of a state-of-the-art review of the design and construction of multiple-span suspension bridges. Based on a paper by David Collings in ICE Proceedings, Bridge Engineering, September 2016. This presentation

1. Multiple Span Suspension Bridges State of
the Art1
Summary presentation of a paper by David Collings
published in ICE Proceedings; Bridge Engineering;
September 2016.
The full paper can be read at
http://www.icevirtuallibrary.com/toc/jbren/169/3

2. Abstract
The paper1 provides a state-of-the-art review of the design
and construction of multiple-span suspension bridges;
This presentation provides a summary of the key
conclusions of the paper;
Much of the recent work on this subject has been carried
out in China, translations of the abstracts of some recent
Chinese papers are included in an appendix to the paper;
The full paper can be read at: .
http://www.icevirtuallibrary.com/toc/jbren/169/3

3. Introduction
Multi-span suspension bridges were relatively common
during the initial development of suspension bridges in
the 19th century when spans were modest and multiple
spans were needed to cross major rivers.
The paper outlines the work of previous generations
together with a summary of modern research, with the
aim of seeing more major multi-span suspension bridges
being proposed.

4. Historical Review
Multi-span suspension bridges were relatively common
during the initial development of suspension bridges in the
19th century when spans were modest and multiple spans
were needed to cross major rivers.
It was known that such bridges were relatively more
flexible than the single span suspension bridge.
A number of methods were developed to stiffen multi span
suspension bridges.

5. The earliest record of a multi-span suspension bridge is
Samuel Brown’s Brighton Chain Pier, painted by Turner and
Constable (this picture). This structure has four spans of
81m. It was constructed in 1823 and destroyed by wind in
1896.

6. In France in the early 19th century multi-span suspension
bridges were also proposed and built to cross major rivers.
One of the most impressive was the Dordogne Cubzac Bridge
of 1839 with 5 spans of 109m, designed by Mark Seguin.

7. Dnper River Bridge
The 6-span 700m long multi-span bridge across the Dnper
River of 1853 was the longest length suspension bridge until
the construction of the famous Brooklyn bridge in 1865.

8. Kiev Dnper Bridge was destroyed in 1920 by retreating troops. A
new multi-span bridge with deep, shaped deck trusses was
erected on the same foundations but also destroyed by war in
1941.

9. A number of multi-span suspension bridges were constructed in
France, many no longer exist (see table 1). That the French
engineers understood the problems of multi-span suspension
bridges is evident from the cable layouts on these bridges, most
of the French bridges have horizontal ties linking the tower tops.

11. For a classic 3-span suspension bridge with short side
spans the behaviour is similar to the single span bridge.
If all three spans are equal the deflections are 6 times
those of the single span; .
A 4-span bridge with short end spans gives deflections
nearer those of a 2-span bridge. For a 4-span bridge
with equal spans the deflection is 7 times as large as a
single span; .
The deflections increase as the number of spans but
flattens out beyond 7 spans, as shown in figure 11.
Suspension System Stiffness

13. For longer more modern multi-span suspension bridges
such as the San Francisco Bay Bridge, Seto-Chuo
Crossing and Kurushima-Kaikyo Bridges (see figure)
the use of conventional single or 3-span bridges placed
end on end has been the favoured solution. This
solution retains the higher stiffness of the classic
suspension bridge, but often requires the construction
of major cable anchorages in deep water.
Methods of Stiffening Multi-Span
Bridges

14. Kurushima-Kaikyo Bridges

15. San Francisco Bay Bridge
The options considered for the San Francisco Bay Bridge prior
to the choice of a back to back structure illustrate some of the
range of solutions (see figure 9).

17. There has been a recent resurgence of interest in multi-
span cable stayed and extradosed2 bridges. Some of
the problems and solutions relevant to cable stay
bridges are similar to those of multi-span suspension
bridges, and similar stiffening methods are often used.
Other Multi-Span Bridge Problems

18. Recently the use of 2-span (3-tower) suspension bridges has
been used for two major bridges over the Yangtze in China3. The
2-span bridge has a number of problems similar to those of full
multi-span bridges. A significant amount of research has been
carried out in China to solve some of the problems, such as
construction methods and saddle slip.

20. Multi-span suspension bridges are appropriate for deep
water crossings, and can be more economic than very
long spans, their use is likely to continue to increase
(figure 5); .
The paper1 has outlined the work of previous
generations, together with a summary of modern
research on multi-span suspension bridges, with the
aim of seeing more major multi-span suspension
bridges being proposed for future estuary and sea
crossings.
Summary & Conclusions

22. References
1. Collings D (2016) Multiple-Span Suspension Bridges:
State of the Art, Proc ICE BE 169(3), 215–231.
http://www.icevirtuallibrary.com/toc/jbren/169/3
2. Collings D, Santiago A S, Extradosed and cable
stayed Bridges: Exploring the boundaries, Proc ICE BE
166, 231-239.
http://www.icevirtuallibrary.com/doi/abs/10.1680/bren.10.00058
3. Zhang M, Wang Y L and Wan T B (2015) Design and
Static Analysis of the Taizhou Yangtzee River Bridge,
China, Proc ICE, BE 168(1), 52–63.
4. Collings D, (2005), Steel-concrete composite bridges,
Thomas Telford, London.
5. Collings D (2015) Long Span Bridges,
http://www.slideshare.net/DavidCollings/long-span-bridges

23. Author
David Collings
BSc CEng FICE
The author is an independent consultant and bridge
designer; a writer 4 and also a researcher and associate
lecturer at the University of Surrey on long span bridges 5.

24. Presentation by CRD and Wolf productions.
The full paper can be read at
http://www.icevirtuallibrary.com/toc/jbren/169/3