Essential steel
plates for bridge use of JFE Steel are reviewed
together with relevant key-technologies. Owing
to Super-OLAC that realizes an ultimate theoretical
cooling rate, high performance steels such
as a TS 570 N/mm2 class
ones and weathering steels with a low PCM
value are materialized by efficient on-line
process which offers a short delivery time
and saving in welding fabrication. As for
weathering steel, two kinds of advanced Ni
type are lined-up for various airborne salt
environments. Also presented herein are new
surface treatment technologies to promote
protective rust formation for a better appearance
of a bridge. Furthermore, longitudinally profiled
(LP) steel plates are lined-up for welding
labor and dead weight reductions and low transformation-temperature
welding consumables are developed for remarkable
fatigue strength of welded joints.
