The paper reports on two test programs that have been performed to assess the ductility and strength of typical connections used for steel braced frame structures. In a first series of tests, connections for back-to-back double angle bracing members were specially designed and detailed to develop different failure modes, including net section rupture, block shear failure, bolt bearing, and bolt or weld shear failure. The inelastic deformation capacity associated with each failure mode could be determined through the tests. In the second experimental program, single and double angle brace connections were removed from existing buildings undergoing demolition and tested under cyclic tension loading to evaluate the failure modes, ductility and predictability. Various failure modes were observed, including failure of the bolts, failure of the gusset plates, failure of the gusset plate-to-column or beam welds, block shear tear out of the brace as well as net brace yielding followed by section fracture. These failure modes ranged from brittle (bolt shear fracture) to ductile (section yielding & fracture).
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