GeoHazards, cilt.6, sa.1, 2025 (Scopus)
To reduce earthquake damage and its effect on the structures, tuned mass dampers (TMDs) are generally positioned on the top of the structures for effectiveness, but existing TMDs on the story levels have problems due to space and additional vertical load issues. Underground-tuned mass dampers (UTMDs) can be used for base-isolated structures to limit deformations of base isolation systems. This study aims to determine the optimum design parameters of an underground tuned mass damper (UTMD) combined with based isolated systems. The best-performing algorithm among the metaheuristic algorithms selected for the optimal design of the UTMD system was investigated. Classical and hybrid forms of several metaheuristic algorithms were used in the methodology. The hybrid of the Jaya algorithm and Teaching Learning-Based Optimization was found to be the most effective one for the reduction of maximum accelerations. The cases limiting the damping of the base-isolation system and various mass ratios of UTMD were also conducted. In conclusion, the control system can reduce the maximum acceleration of the optimum base-isolated structure by 4% to 23% according to the mass ratio of UTMD and provide a low-damping isolation design as the optimum one.