摘要 |
PROBLEM TO BE SOLVED: To provide a method for suppressing the generation of fatigue damage of a welded structure, which can securely suppress the generation of fatigue damage such as a fatigue crack in the weld portion of the welded structure such as a steel bridge, and a tool for forming an impact trace used therein, and the welded structure.SOLUTION: In the method for suppressing fatigue damage of the welded structure, using a tool 6 for forming the impact trace on the surface of the base material 1 adjoining the weld bead 3, hammer peening or ultrasonic shock processing is applied to form the impact trace 5. The tool 6 used for forming the impact trace has a planate impact trace formation surface 7 in the front end thereof, which is formed to be flat, and is formed into a circular shape of which the radius is 1.5 mm or more, 3.0 mm or less. By the tool 6 for forming the impact trace, an impact trace 5 of which the maximum depth is 0.03 mm or more, less than 0.50 mm is formed continuously along a weld bead 3 in the zone from the toe 4 of the weld bead 3 to 5 mm in the base material 1 side. |