Abstract

Abstract
Seismic Response of Building Frames Controlled using Semi Active Multiple Tuned Mass Dampers
Alireza Torkaman Rashid

Earthquakes induce lateral forces on buildings that could result in damage and potential for collapse of the structures. Therefore, it is necessary to control and design the structures for resisting the forces due to ground motions. Various energy dissipating systems have been developed and used in the past. The application of the Tuned Mass Damper (TMD) has been proven to be effective in tall buildings for the control of vibrations due to wind or earthquake. In this research, for better performance of buildings, Multiple Tuned Mass Damper (MTMD) distributed in different floors of a building has been used and the seismic performance of the building has been studied. A modal analysis has been conducted and the TMDs were placed in a structure and tuned based on its dominant modes. Furthermore, the influence of the distribution of the mass on different levels of a structure has been studied. It is found the MTMDs are very effective in controlling the vibration of a building and compared to a single TMD placed at the top floor. To further improve the performance of a building frame with MTMDs, multiple Magnetorheological dampers (MR dampers) have been paired with each of the MTMDs to create a semi-active system of Semi-Active Multiple Tuned Mass Damper (SAMTMD). While application of MTMDs were explored by other researchers, the use of SAMTMD is a novel concept introduced in this thesis. The seismic demands of the structure including displacement, velocity, acceleration, and the energy dissipating capacity of the structure have been significantly improved with the SAMTMD system.