This paper presents the experimental investigation of cold-formed steel double-shear bolted connections where both the bolt head and the nut are not in contact with the outer sheets. The inner sheet of each specimen is not constrained from out-of-plane distortion or bulging downstream of the bolt, and fails in bearing. Based on a series of tests involving specimens having bolt diameters ranging from 12 to 16 mm and sheet thicknesses ranging from 1.5 to 3.0 mm, it has been found that the absence of out-of-plane constraint in untightened bolted connections leads to much lower bearing capacities than predicted by the specification's bearing strength equation. The effect is more pronounced for thinner sheets. An interesting finding is that the threaded bolt specimens had higher bearing capacities than the corresponding ones with shank bolts. It appears that the bolt threads provided some out-of-plane constraint to the connected sheet.
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