This study evaluated the mechanical joining characteristics of substrate Al7075 using the filler metals of ER5356 and Al7075 to secure the joining integrity of the specimens by GTAW. The results of radiographic test show that the welded specimens meet the first level standard of KS D 2042. Besides, welding defects were not occurred. The tensile strengths of the specimens using the filler metals of Al7075 and ER5356 had 240MPa and 252MPa, respectively. The yield strengths were 132MPa and 120MPa, respectively. In case of using the filler metal of Al7075, However, in case of using the filler metal of ER5356, Two filler metals of Al7075 and ER5356 were similar to each other in tensile and yield strength.

Recently, study on the application of sustainable materials to building and civil structure fields has been increased. Especially, the usage of aluminum alloys can improve durability of structures due to it’s high corrosion resistance. In this study, to investigate the ultimate behaviors such as ultimate strength and fracture mode of single shear bolted connections with aluminum alloys (7075-T6), experiments were conducted. Main variables are bolt arrangement and end distance parallel to the direction of load. As a result, the specimens failed by shear out fracture and block shear fracture and also the specimens with long end distance were accompanied by curling (out of plane deformation). The curling led to reduction of ultimate strength or rigidity. Futhermore, pattern of strain distribution was investigated according to curling occurrence.