To provide a displacement stopper and a composite girder reducing the number of studs of a composite girder, which has been difficult in conventional materials and designing methods, and obtaining advantages like improvement of manufacturing efficiency of a steel girder, rationalization of a bridge structure, and cost reduction.
As the displacement stopper of the composite girder including the steel girder 2 and a concrete floor slab 1 integrated with an upper flange 4F of the steel girder 2, headed studs 3F formed of an FCA steel material is used. The FCA steel material has; the steel chemical composition of, by mass%, ≥0.01% and ≤0.15% C, ≥0.03% and ≤0.6% Si, ≥4/3% and ≤2.0% Mn, >0.005% and ≤0.10% Sol. Al, ≥0.0005% and ≤0.008% N, and the balance Fe and inevitable impurities; the structure composed mainly of bainite and martensite, or either one of bainite or martensite; the half-value width of X-ray diffraction intensity from the (200) face of ≥0.20 degrees, and excellent fatigue crack propagation resistance.
TONEGAWA TARO
YUGAWA MASAYUKI
Satoshi Kumon