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This study deals with the behaviour of duplex stainless steel bolted connections. The aim of the study is to respond to the question if the current stainless steel design specifications are able to predict the behaviour of such connections. Firstly, the net cross-section capacity of duplex stainless steel plates subjected to tensile loading are presented. They were conducted to obtain the stress–strain curves and tensile fracture behaviour used to support the finite element (FE) fracture simulations. Secondly, nonlinear FE models are developed for duplex stainless steel bolted connections subjected to tensile loading. The FE models are validated against experimental data in terms of load–displacement curves, failure modes and ultimate loads. Then, a numerical parametric study that consists of 133 duplex stainless steel grade EN 1.4162 bolted connection specimens is carried out. The failure modes of bolted connections are carefully examined, including combined tear out and bearing, bearing and net section, looking at the influence of parameters such as end distance, edge distance and spacing between the bolts in the connections. The results are compared to the design rules prescribed in the current stainless steel design specifications. Generally, it is found that the Australian/New Zealand (AS/NZS), American (SEI/ASCE) Specification and European codes conservatively predict the ultimate strengths of the bolted connections, whereas the strengths predicted by the AS/NZS and SEI/ASCE specifications are overall more accurate and less scattered. • Net cross-section capacity of duplex stainless steel plates are presented. • Numerical models of duplex stainless steel bolted connections are validated. • Duplex stainless steel bolted connections are parametrically studied. • The current design specifications provide conservative strength predictions. • The current design specifications generally predict the correct failure modes. [ABSTRACT FROM AUTHOR]

This paper presents an experimental investigation into the structural behaviour and strength of swage-locking pinned aluminium alloy double-shear connections. It reports the failure modes (shear-out, bearing, block shear and net section failures), ultimate resistances and load-deformation histories. A total of twenty-three tests with four different aluminium alloy grades and various geometric variables, including end distances, edge distances and pin spacings, were carried out. The experimental results were utilized to assess the accuracy of the current American, Australian/New Zealand and European design provisions, as well as recent proposals by Teh and co-workers, extended to the design of aluminium alloy shear connections. The current code equations are shown to provide overly conservative strength predictions for the tested specimens. The equations of Teh and co-workers provide significantly more accurate strength predictions than the codes, though the test results indicate that there is still scope for more efficient design equations for swage-locking pinned aluminium alloy shear connections. • Twenty-three tests conducted on swage-locking pinned aluminium alloy shear connections. • Four different aluminium alloy grades and various geometric variables were considered. • Test results were utilized to assess the accuracy of the current design codes. • It was found that the equations of Teh and co-workers are more accurate than codified methods. [ABSTRACT FROM AUTHOR]

• Flat-ended circular hollow sections were tested in tension. • Three bolt configurations were established in flattened ends. • Bearing failure and net-section fracture were observed. • The test load increased with increase in the number of bolts. • An adjusted bearing coefficient is suggested for bearing. Experiments were performed to investigate the behaviour of 28 circular hollow sections (CHSs) in tension, with flat ends and three bolt configurations (2, 3 and 4 bolts). The length of the members between the flat ends was kept constant at 1500 mm for all CHSs, and the sizes of the sections ranged from 60.3x2.0 to 101.6x4.5. Two modes of failure were observed, viz; bearing failure (BF) and net-section fracture (NSF). CHSs connected with 2 bolts failed in bearing, whilst net-section fracture was dominant in sections with 3 and 4 bolts. The notion that the change in the number of bolts can lead to different behaviours of the connections is a significant contribution to knowledge, particularly if flat-ended CHSs are used as structural truss elements. This paper demonstrates that the sections are capable of supporting large loads, however, the capacity of the tested specimen did not reach the full yield strength. It is apparent from the tensile strengths that a larger increase in strength was accomplished when the number of bolts was increased from 2 to 3 bolts than from 3 to 4 bolts. A comparison of the tensile strength with the strengths predicted by the North American standard (AISI S100-16w/S1-18), Australia/New Zealand standard (AS/NZS-4600:2018) and European standard (EN 1993–1-3) confirm that both standards provides a reasonable assessment of the strength of the 3 and 4 bolt configuration, which failed purely by net-section fracture. However, for the 2-bolted connections, which failed in bearing, it is proposed to use AS/NZS 4600:2018, with a bearing coefficient of C = 2.85, instead of C = 3.0, to increase the accuracy of the bearing strength expression for these specimens. [ABSTRACT FROM AUTHOR]