Patent ID: 7748596

Claim:
A welded structure comprising steel plates having excellent properties to prevent the propagation of brittle fracture parallel to the surface of the steel plates in a weld direction of a butt weld of welded joints, characterized by the welded structure includes a repair weld over the butt weld having a greater toughness than that of the butt weld and that an angle φ of an outer edge of the repair weld with respect to the weld direction of the butt weld parallel to the surface of the steel plates is not less than 10 degrees and not more than 60 degrees in a region to arrest brittle fracture in the butt weld in the weld direction of the butt weld parallel to the surface of the steel plates in butt-welded joints of steel plates, said steel plates having a thickness of 20 mm or more wherein the repair weld does not extend the entire length of the butt weld and wherein the angle φ does not intersect the surface of the plates or the butt weld.