Modeling level selection for seismic analysis of concrete-filled steel tube/moment-resisting frames by using fragility curves

摘要

The seismic behavior of plane moment-resisting frames (MRFs) consisting of I steel beams and concrete-filled steel tube (CFT) columns is investigated in this study. More specifically, the effect of modeling details of each individual component of CFT-MRFs, such as the composite CFT columns, the beam-column connections, the panel zones, and the steel I beams on their seismic behavior, is studied through comparisons against available experimental results. Then, fragility curves are constructed for three typical CFT-MRFs, designed according to European codes, for various levels of modeling sophistication through nonlinear time-history analyses. On the basis of these fragility curves, one can select the appropriate modeling level of sophistication that can lead to the desired seismic behavior for a given seismic intensity.