Key Factors that Affect the Behavior of Steel Beams and Columns in Special Moment Frames

Steel Special Moment Frames (SMFs) are favored seismic force-resisting systems due to their architectural flexibility and high ductility. While shallow columns (section depth less than 356 mm) were commonly used in these before the Northridge earthquake, deeper greater have become more popular recent years meet code-enforced story drift requirements economically. However, limited research exists on hinging behavior of deep under axial compression cyclic drift. Since exhibit larger slenderness ratios susceptible local global buckling, understanding is crucial. This study investigates fifteen four-story steel SMFs using finite element program simulations, focusing four key factors affecting frame behavior: 1) Column bracing, 2) Beam 3) stiffening, 4) Strong Weak (SCWB) ratio. The influence force level column section properties also examined. Results demonstrate that may experience and/or instabilities at relatively low levels. Findings suggest SMF performance can be enhanced by bracing top bottom levels beam flanges adding stiffeners columns' web. Controlling shortening increasing SCWB ratio recommended.