구조물 용접부의 잔류응력 및 강도 평가에 관한 연구 = Evaluation of The Residual Stresses and Strength on Structure Welding Joints

다국어 초록 (Multilingual Abstract)

This paper is to investigate the influence of weld residual stresses on the fatigue crack growth behaviors in the vertical direction to the weld bead. So, Co2 Automatic welding was performed on the ASTM A516 grade 60 Steel.
For pad-on-plate skip, continuous fillet welding specimens and PWHT specimen, fatigue crack initiation is generally initiated at weld starting and end toe zone, and ruptured at weld starting toe zone. Fatigue life of pad-on-plate continuous specimen is increased more than that of pad-on-plate skip fillet welding specimen about 85% under low load, about 20% under high load, and decreased than that of two-pad continuous welding specimen about 85%. In da/dN-??K curve under low load, pad-on-plate skip fillet welding specimen showed retardation on the initial crack, and the fatigue crack growth rate at the low region of ??K greater specimen E(3.8×10-6mm/cycle). And the fatigue life of welding specimen was smaller than that of PWHT specimen.