抄録
The recent trends for long span bridges and their using steels are reviewed. The newly developed structural steels, that is high performance steels for bridge construction, are also reviewed in this paper. As the span length increases, higher strength steel, increasing weldability for decreasing weld fabrication cost and bare use of weathering steel for decreasing maintenance cost are required. To meet these requirements, high strength steel, steel allowing low-temperature preheating, steel for cold bending, weathering steel for coastal region, longitudinally-profiled (LP) steel plate and high-strength steel wire for bridge cables have been developed. Especially newly developed weathering steel and its surface treatment for minimum maintenance cost are reviewed in detail.
