Seismic Collapse Response of a Four Story Steel Special Moment Frame with Deep Columns

The collapse potential of a four-story steel special moment frame (SMF) under a set of ground motions is evaluated using high fidelity computational simulation. The SMF is designed in accordance with current design requirements and employs reduced beam sections and deep columns. The computational model is capable of explicitly accounting for the interaction of local and global instability within the SMF. A study is performed to investigate the effect of the level of gravity loads on the collapse response of the frame. Even though all columns satisfy highly ductile requirements in current seismic provisions, they become increasingly vulnerable to global buckling as the gravity -induced axial load increases.