A Comparison on the Ultimate Behavior of Bolted Connections with Aluminum Alloys(6061-T6) according to Bolt Shear Loading

알루미늄 합금(6061-T6) 전단접합 방법에 따른 볼트접합부의 구조거동의 비교

Previous study on the ultimate behavior of single shear bolted connections fabricated with aluminum alloys (6061-T6) shows that in some specimens with a long end distance(e), curling ; out of plane deformation occurred and it caused the sudden strength drop of bolted connections. In this paper, double shear bolted connections with same aluminum alloys(6061-T6) were tested for comparing with single shear bolted connections in terms of ultimate strength and curling effect. Specimens with three variables (bolt arrangement, end distance(e) and edge distance(b)) were planned. All of specimens failed by block shear or tensile net-section fracture. Ultimate strengths of specimens with typical block shear fracture have increased with the increase of end distance(e). Also, it can be known from the comparison that the curling led to strength reduction by 4~30%. An investigation on reliability of current design standards for bolted connection was conducted. Ultimate strengths and failure mechanisms predicted by AISI (American Iron Steel Institute) and AAA(American Aluminum Association) were compared with those of test results. Comparison results indicate that current design standards can not predict correctly ultimate strength and failure mechanism for bolted connection with block shear fracture.