Fragility Assessment of Beam-Slab Connections for Informing Earthquake-Induced Repairs in Composite-Steel Moment Resisting Frames

Earthquake loss estimation in composite-steel moment resisting frames (MRFs) necessitates a proper of the level damage steel beam-to-slab connections. These usually feature welded headed shear studs to ensure composite action between concrete slab and beam. In partially beams, earthquake-induced surrounding occurs due stud slip demands. Within such context, this paper proposes slip-based fragility functions estimate probability being or exceeding four states beam-slab include cracking crushing vicinity studs, as well themselves. The developed are obtained from gathered dataset 42 cyclic push-out tests. They incorporate uncertainty associated with specimen-to-specimen variability, along epistemic arising finite number available experimental results. An application proposed is conducted on six-story building MRFs. It shown that connections height only exhibit light (i.e., crack sizes 0.3 mm less) at design basis seismic events. At intensities low occurrence event return period 2475 years) nonlinear simulations suggest 25% reduction resistance beam depths 500 less not imperative maintain integrity connectors.