NCBF3-2: UW Non-Seismic Concentrically Braced Frame (NCBF) with Bolted Split Shear Tab and Ductile HSS Brace

This specimen consisted of a single-bay one-story concentrically braced frame with single-diagonal bracing. The frame was intended to be representative of existing non-seismic concentrically braced frames (NCBFs) with split bolted shear tab connections at brace-beam-column intersections. The connections were deficient with respect to the 2010 AISC Seismic Provisions but the brace was a highly ductile HSS. Connection deficiencies included gusset plate yielding of the Whitmore section, gusset plate shear yielding, beam-to-shear tab bolt bearing and shear, gusset plate-to-shear tab bolt bearing and shear, brace net section rupture, and brace block shear rupture. AWS E71-T11 weld metal, which does not meet minimum toughness requirements for demand critical welds, was used. The specimen was loaded quasistatically through a load beam bolted to the north beam using a reversed cyclic increasing amplitude loading protocol. Traditional physical sensors and optical sensors were installed on the specimen. Portions of the specimen were whitewashed to detect yielding.