Editing Suspension bridge (section)

===Suspension cable types===
[[File:Höyryputkisilta Näsijärvellä vuonna 1979.jpg|thumb|A former [[steam]] [[Pipeline transport|pipeline]] suspension bridge on the [[Lake Näsijärvi]] in [[Tampere]], [[Finland]], in 1979]]

The main suspension cables in older bridges were often made from a chain or linked bars, but modern bridge cables are made from multiple strands of wire. This not only adds strength but improves reliability (often called redundancy in engineering terms) because the failure of a few flawed strands in the hundreds used pose very little threat of failure, whereas a single bad link or [[eyebar]] can cause failure of an entire bridge. (The failure of a single eyebar was found to be the cause of the collapse of the [[Silver Bridge]] over the [[Ohio River]].) Another reason is that as spans increased, engineers were unable to lift larger chains into position, whereas wire strand cables can be formulated one by one in mid-air from a temporary walkway.

====Suspender-cable terminations====
Poured sockets are used to make a high strength, permanent cable termination. They are created by inserting the suspender wire rope (at the bridge deck supports) into the narrow end of a conical cavity which is oriented in-line with the intended direction of strain. The individual wires are splayed out inside the cone or 'capel', and the cone is then filled with molten lead-antimony-tin (Pb80Sb15Sn5) solder.<ref>T R Barnard (1959). "Winding Ropes and Guide Ropes:"   Mechanical Engineering. Coal Mining Series (2nd ed.). London: Virtue. pp. 374–375.</ref>