Moment Frame

In a moment frame, the beam-to-column connections are designed to transfer bending moment — not just shear — between members. This rigidity allows the frame to resist lateral loads through frame action (the deformation of the beams and columns in double curvature). Special Moment Frames (SMF) are designed and detailed to provide ductile behavior in seismic events, with carefully designed connection zones that allow yielding to absorb seismic energy. Moment frames are common in steel office buildings, open-plan commercial spaces, and industrial structures where shear walls or braced frames would obstruct the space. The connections in seismic moment frames require careful detailing and typically inspection during construction.