Abstract
The commentary to the North American cold-formed steel specification recommends physical testing to determine the performance of a bolted connection where the plies are not in contact with each other. This paper presents the laboratory test results of 120 such specimens with sheet thicknesses ranging from 0.55 to 3.0 mm, bolted with 10-, 12-, or 16-mm bolts. Finite-element analyses support the experimental finding that the bearing failure of an unconfined bolted connection is not associated with shear fracture but with crimpling of the critical ply. The bearing capacity varies with the square root of the bolt diameter and nonlinearly with the sheet thickness. Dimensionally consistent and continuous design equations are derived and verified against the results of the laboratory tests and finite-element analyses, the latter supplementing the former with configurations involving 8-mm bolts. The derived relationships between the bearing capacity and the sheet thickness and bolt
Abstract
This data paper presents the experimental investigation of unconfined cold-formed steel double-shear bolted connections where the applied load was stopped at different stages of loading (25% or 65% of the ultimate failure load under monotonic loading) followed by unloading, and finally reloading until failure. A total of 78 bolted connections of cold-formed steel subjected to loading-unloading and reloading conditions with sheet thicknesses ranging from 0.55 to 3.0 mm, bolted with 10, 12, or 16-mm bolts were investigated and compared to the identical specimens subjected to monotonic loading. The failure mode of the specimens tested under both loading conditions was bearing of the inner sheet. The test results show that ultimate capacities obtained from unloading and reloading tests were, on average, lower than those obtained from the monotonic tests. A similar trend was also observed for the displacement corresponding to the ultimate loads. However, the effects of sheet thi