In this study, cyclic loading tests were conducted to clarify the extremely low cycle fatigue crack (ductile crack) initiation and final failure mode in thick-walled steel beam-column connections with different conditions of the finished weld bead. Three test specimens are manufactured with the weld bead by toe burr grinding, R finishing and as-weld, respectively. Discussions of ductile crack initiation and progression, local strain and load-displacement relation are made to investigate the effect of the condition of the finished weld bead.
