2004 Volume 11 Issue 42 Pages 121-132
Recently, the quality of steel has been remarkably improved, and high performance steel for bridge has also been developed. However, when it comes to how much, it has not been clarified. In this paper, first, we investigated the number of 1412 steel on the basis of the mill sheet in order to clarify their quality. Investigated items were tensile strength, yield strength, charpyabsorbed-energy, PcM(cracking parameter of material) and Ceq(carbon equivalent), and these steel mechanical properties were shown. Then, we also showed the degree of improvement in the quality, comparing with the data 30 years ago.