Abstract: Provided is a method for preventing corrosion of a cable including a plurality of bundled wires and a covering tube which covers the plurality of wires, the method including a mixed gas generation step of mixing a low-oxygen gas having an oxygen concentration lower than an oxygen concentration of air with the air, and a mixed gas supply step of supplying the mixed gas into the covering tube to flow the mixed gas around each of the wires.

Abstract: A cable-stayed suspension bridge having characteristics of a cable stayed bridge and those of a suspension bridge at the same and time and using one-box and two-box girders in combination is disclosed. The bridge grinder of the cable-stayed suspension bridge includes one-box girders that each extend to both sides through the respective one tower and a two-box girder set in a central portion of the center span between towers in the length direction of the bridge girder. The cable-stayed suspension bridge includes cable-stayed structures in which a respective one of the one-box girders is supported by the tower with plural cables and a suspension structure in which the two-box girder is supported by the plural towers with two main cables and plural hanger ropes. The two-box girder has a central ventilation opening in the central portion as viewed in a transverse direction thereof.