Steel wire for the prestressing of concrete We have 2 kinds of prestressing steel wire, one kind is round steel wire, the other side is Spiral Ribbed Steel Wire.Steel Wire diameter from 4mm to 12mm,Tensile Strength from 1470mpa, 1570pa,1670pa to 1770pa. Prestressed steel wire can be used in construction, bridges, and airport buildings. Due to its excellent mechanical properties and corrosion resistance, prestressed steel wire plays an important role in modern construction projects.