The ends of the beams in a special moment resisting frame (SMRF) undergo significant inelasticity during large earthquakes. Due primarily to a lack of data and a concern for premature fracture, fasteners are prohibited in this region of the beam which is referred to as the protected zone. However, the restriction on fasteners in the protected zone creates issues in construction and as a result unauthorized attachments are not uncommon. Full-scale beam-to-column tests have been conducted to investigate the cyclic behavior of SMRF connections with powder actuated fasteners (PAF) applied in the protected zone. Both bolted extended end plate connections and reduced beam section connection configurations were tested. Several specimens included PAF in typical fastening patterns that might represent deck attachment to the top flange of the beam or connection of cold-formed steel partition walls to the underside of the beam. One specimen included a grid of PAF over both flanges to investigate the effect of PAF that are applied in the local buckle locations. The behavior of specimens with PAF is compared to that of control specimens. For the configurations examined in this study, PAF were not found to have a significant effect on hysteretic behavior.
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