Recently, since stainless steels have important properties such as superior durability, fire resistance and corrosion resistance, they are widely used as non-structural element as well as structural element in building construction. In this study, experimental studies have been performed to investigate the structural behaviors such as ultimate strength and fracture mode of double shear two-bolted connection and four-bolted connection with austenitic stainless steel(STS304) and varied end distance. In case of two-bolted connection, all of specimens showed block shear fracture. And four-bolted connection failed by block shear fracture or net section fracture at test end.

In this paper, block shear fracture behavior in base metal of fillet-welded connection fabricated with duplex stainless steel (STS329FLD) were investigated through experimental procedures. Main variables are weld lengths in the longitudinal and the transverse directions of applied force. As a result, test specimens failed by typical block shear facture (the combination of tensile fracture and shear-out fracture) in base metal not weld metal. Ultimate strength of the specimens tended to get higher with the increase of the weld lengths.