Effect of connection fracture dispersion on seismic demands of welded steel moment frames

Appropriate modeling of connections behavior is needed for seismic evaluation of structures. However, large dispersion is observed in welded steel moment frame connections performance during recent earthquakes and experimental tests. In this study, the effect of dispersion in pre-Northridge connections characteristics is investigated. Two mid-rise steel moment frames are designated. Various types of fractures in beam-column connections with various configurations are modeled. Sensitivity study is carried out on parameters affecting the structural response for two probability levels by implementation of nonlinear dynamic analysis. Results show that variation in connection characteristics moderately affects the displacement demands of structures.