Recent testing conducted by NBM Technologies provides cyclic characterization of both deck-to-deck sidelap and deck-to-frame structural connectors. The tests cover 18 to 22 gauge deck, and a variety of connector conditions including: screws, PAFs, and welds. The results highlight the monotonic strength and stiffness of welded connections, and the cyclic post-peak ductility and residual capacity of mechanical connections.
Nestable deck-to-deck screwed sidelaps exhibited fairly high strength variability in the NBM testing. A small follow-on effort funded by CFSRC investigated the impact of fastener location on the performance of this sidelap connection. The test results indicated that when sidelaps are installed in the corner of the deck the connection has higher strength and a small reduction in ductility. Further, even fasteners with only a 1/4 in. edge distance (violating AISI S100’s 3d edge criteria) had strength in good agreement with AISI S100 predictions.
The results were presented by SDII researcher Shahab Torabian in two papers at the 2018 International Specialty Conference on Cold-Formed Steel Structures, click here for the general paper across connection types, and click here for the detailed investigation of screwed sidelaps.