WELDED STRUCTURE EXCELLENT IN BRITTLE-CRACKING PROPAGATION STOPPING CHARACTERISTICS

摘要

Provided is a welded structure suitable for a hull structure and excellent in brittle-cracking propagation stopping characteristics. The welded structure is provided with a fillet welded joint having an unwelded portion (4) left on the abutting face of a web (1) against a flange (2). A percentage (X) (= 100.n/L) (%) to the sum (L) of the width (n) of the unwelded portion (4) and the leg length (3 (3a and 3b)) of the left and right fillet welded joints in the joint section of the fillet welded joint, and the brittle-cracking propagation stopping toughness (Kca (N/mm3/2)) at the using temperature of the flange satisfy X (%) >= {5900-Kca(N/mm3/2)}/85. The unwelded portion (4) in the fillet-welded joints is given a width of 15 to 90 % of the sum of the thickness (t) of the web (1) and the leg length (3 (3a and 3b)) of the left and right fillet welded joints. In case the web has the butt-welded joint portion of the thickness (t), the percentage (X) (%) and the brittle-cracking propagation stopping toughness (Kca)(N/mm3/2) satisfy the aforementioned formula.