Design Criteria for Bolted Connection Elements in Aluminum Alloy 6061

Abstract

Plates frequently find use as connecting elements in structures built from aluminum alloys. Many structural elements employ mechanical fasteners. Design of connections necessitates that due consideration be given to: (a) bolt or rivet failure, (b) progressive bearing distress of material adjacent to the fastener(s), (c) net-section tensile failure, and (d) tear out of the fastener group(s). Current design provisions for block shear failures of bolted and riveted joints in aluminum-based alloys make use of models initially developed for structural steels or, alternatively, fail to address an estimation of joint capacity. Shear failure of aluminum connecting elements is the focus of this paper. An experimental and analytical program was undertaken with the objective of studying block shear failure of aluminum connecting elements. Twenty aluminum alloy 6061-T6 gusset plates, representing four different bolt patterns, were mechanically deformed. Models to estimate the capacity of the joints are examined and compared with experimental results. Strain distribution around the periphery of the connections were measured and compared to finite element predictions. The correlations between the design models and experimental observations are highlighted.