Editing Simple suspension bridge (section)

==Comparison to other types==
[[File:TWC Hokitika Gorge • Stewart Nimmo • MRD 13.jpg|alt=|thumb|A swingbridge at the [[Hokitika Gorge]] on the [[West Coast, New Zealand|West Coast]] of [[New Zealand]].]]
In some contexts the term "simple suspension bridge" refers not to this type of bridge but rather to a [[suspended-deck bridge]] that is "simple" in that its deck is not stiffened.<ref>{{cite EB1911|wstitle= Bridges/History 1 |volume= 04 | pages = 533&ndash;538; see page 536 |quote= 8. (c) Suspension Bridges.—A suspension bridge consists of....." }}</ref><ref>{{cite book
|title=Theory of structures
|author=Arthur Morley
|publisher=Longmans, Green, and Co.
|year=1912
|pages=[https://archive.org/details/theorystructure03morlgoog/page/n509 482]-484, 574
|url=https://archive.org/details/theorystructure03morlgoog
|quote=simple suspension bridge.
}}</ref>  Although simple suspension bridges and "simple" suspended deck bridges are similar in many respects, they differ in their physics.  On a simple suspension bridge, the main cables (or chains) follow a [[hyperbolic function|hyperbolic]] curve, the [[Weighted catenary|catenary]].  This is because the main cables are free hanging.  In contrast, on a suspended deck bridge (whether "simple" or not) the main cables follow a [[parabola|parabolic curve]].  This is because the main cables are tied at uniform intervals to the bridge deck below (see [[Catenary#Suspension bridge curve|suspension bridge curve]]).

The differences between these two curves were a question of importance in the 17th century, worked on by [[Isaac Newton]].<ref>{{cite book
|title=The Mathematical Papers of Isaac Newton: Volume 5: 1683–1684
|author=Isaac Newton
|editor=D. T. Whiteside
|publisher=Cambridge University Press
|year=2008
|isbn=978-0-521-04584-1
|pages=664
|url=https://books.google.com/books?id=sf5z2h93_wcC
}} Appendix 2, footnote 373 on pages 285-287, footnote 1 on pages 520-521, footnote 5 on pages 521-522</ref> The solution was found in 1691, by [[Gottfried Leibniz]], [[Christiaan Huygens]], and [[Johann Bernoulli]] who derived the [[equation]] in response to a challenge by [[Jakob Bernoulli]].<ref name="Lockwood124">{{cite book |title=A Book of Curves|first=E.H.|last=Lockwood|publisher=Cambridge|year=1961
|chapter=Chapter 13: The Tractrix and Catenary|chapter-url=https://archive.org/details/bookofcurves006299mbp}}
* {{cite book|last=Salmon|first=George | title=Higher Plane Curves
|url=https://archive.org/details/treatisehigherpl00salmrich|publisher=Hodges, Foster and Figgis|year=1879|pages=[https://archive.org/details/treatisehigherpl00salmrich/page/n314 287]–289
}}</ref> Their solutions were published in the ''[[Acta Eruditorum]]'' for June 1691.<ref>{{citation|first=C.|last=Truesdell|title=The Rotational Mechanics of Flexible Or Elastic Bodies 1638–1788: Introduction to Leonhardi Euleri Opera Omnia Vol. X et XI Seriei Secundae|location=Zürich|
url=https://books.google.com/books?id=gxrzm6y10EwC&pg=PA66|page=66|publisher=Orell Füssli|date=1960|isbn=9783764314415}}</ref><ref name="calladine" >{{citation|first=C. R.|last=Calladine|title=An amateur's contribution to the design of Telford's Menai Suspension Bridge: a commentary on Gilbert (1826) 'On the mathematical theory of suspension bridges'|journal=Philosophical Transactions of the Royal Society A|date=2015-04-13|volume=373|issue=2039|page=20140346|doi=10.1098/rsta.2014.0346|pmid=25750153|pmc=4360092|bibcode=2015RSPTA.37340346C}}</ref>

A [[stressed ribbon bridge]] also has one or more catenary curves and a deck laid on the main cables.  Unlike a simple suspension bridge however, a stressed ribbon bridge has a stiff deck, usually due to the addition of compression elements (concrete slabs) laid over the main cables.  This stiffness allows the bridge to be much heavier, wider, and more stable.