Self-Centering Beams for Seismically Resilient Moment Frames

Abstract

Self-centering beam moment frames (SCB-MFs) have been developed with the capability of resilient performance during large earthquakes by virtually eliminating residual drifts and concentrating structural damage in replaceable fuses. The self-centering beams (SCBs) can be shop-fabricated with the self-centering mechanism built into the beam unit, thus eliminating deformation incompatibility with the surrounding gravity framing that is associated with some other self-centering systems. Furthermore, the SCB-MFs allow for conventional field construction methods, making them more accessible to the construction industry. A parametric study was performed on single self-centering beam units to investigate the sensitivity of the SCBs to a variety of design variables. The results of this study show that these units can be implemented in a wide variety of configurations for various beam depths and moment capacities. Additionally, the ability of the system to dissipate seismic energy while minimizing residual drift was demonstrated. Ultimately, this study has shown that SCB-MFs are a viable seismic force resisting system for reducing structural damage due to large earthquakes and have the potential to limit the cost and time required to make a building operational following a strong ground motion.