Seismic Vulnerability Control of Steel Moment–Resisting Frames Using Optimum Friction Tuned Mass Damper

Friction tuned mass damper (FTMD) as one of the variety passive devices is a combination of the traditional TMD system with dry friction damping. This study presents the seismic vulnerability control of a 10-story steel moment–resisting frames (SMRFs) equipped with an optimized FTMD system. The optimized FTMD system placed in the roof story of the SMRF is first found through minimizing the maximum value of the Park–Ang damage index of stories averaged over seven scaled earthquake excitations. Further, the seismic damage induced by the scaled earthquake excitations is uniformly distributed throughout the height of the SMRF. Then, the seismic assessment of the SMRF with the optimized FTMD is implemented by fragility analysis. Results indicate that the seismic damage over the height of the optimized FTMD-equipped SMRF is uniformly distributed in comparison with that of the uncontrolled SMRF. The seismic fragility assessment also indicates that the optimized FTMD improves the seismic performance of the controlled SMRF compared to that of the uncontrolled SMRF at different damage states.