Editing Tensile structure (section)

=== Cables ===

Cables can be of [[mild steel]], [[High-strength low-alloy steel|high strength steel]] (drawn carbon steel), [[stainless steel]], [[polyester]] or [[Aramid|aramid fibres]]. Structural cables are made of a series of small strands twisted or bound together to form a much larger cable. Steel cables are either spiral strand, where circular rods are twisted together and "glued" using a polymer, or locked coil strand, where individual interlocking steel strands form the cable (often with a spiral strand core).

Spiral strand is slightly weaker than locked coil strand. Steel spiral strand cables have a [[Young's modulus]], ''E'' of 150±10&nbsp;kN/mm<sup>2</sup> (or 150±10 [[gigapascal|GPa]]) and come in sizes from 3 to 90&nbsp;mm diameter.{{Citation needed|reason=The information is probably country/manufacturer specific and needs a source.|date=April 2016}} Spiral strand suffers from construction stretch, where the strands compact when the cable is loaded. This is normally removed by pre-stretching the cable and cycling the load up and down to 45% of the ultimate tensile load.

Locked coil strand typically has a Young's Modulus of 160±10&nbsp;kN/mm<sup>2</sup> and comes in sizes from 20&nbsp;mm to 160&nbsp;mm diameter.

The properties of the individual strands of different materials are shown in the table below, where UTS is [[ultimate tensile strength]], or the breaking load:

{| class="wikitable"
|-
! Cable material
! ''E'' (GPa)
! UTS (MPa)
! [[Strain (materials science)|Strain]] at 50% of UTS
|-
| Solid steel bar
| 210
| 400–800
| 0.24%
|-
| Steel strand
| 170
| 1550–1770
| 1%
|-
| Wire rope
| 112
| 1550–1770
| 1.5%
|-
| Polyester fibre
| 7.5
| 910
| 6%
|-
| Aramid fibre
| 112
| 2800
| 2.5%
|}