Seismic design and performance assessment of a retrofitted building with tuned viscous mass dampers (TVMD)

Vibration control technologies have been widely implemented for the seismic retrofitting of buildings in high seismic regions. Among various vibration control devices, the tuned viscous mass damper (TVMD) has proven effective in mitigating both lateral inter-story drifts and floor accelerations. This paper presents the seismic design and performance assessment of a retrofitted structure located in a highly seismic area. The existing masonry building is being retrofitted into a steel frame-jacketed masonry wall interacting structural system installed with TVMDs. A simplified iterative design process is proposed for the tuning design of TVMDs used in the retrofitted structure, which is based on the fixed-point method. The seismic responses of the buildings are calculated using non-linear dynamic analysis in OpenSees. Applying the FEMA P-58 approach, the seismic performance of the buildings as measured by the repair cost and repair time is evaluated. The findings reveal that the majority of the structural damage is focused within the masonry walls, coupling beams, and non-structural components. Use of TVMDs results in reduced maximum inter-story drifts that when subjected to very rare earthquake (VRE) shaking are up to approximately 40% lower in both transverse and longitudinal directions compared with the uncontrolled structure. Owing to the effective control of seismic damage to both structural and non-structural components, the TVMD-equipped structure achieves a 42% reduction in median repair cost and a 46% reduction in median repair time at VRE compared with the uncontrolled building. The seismic performance assessment results also illustrate the advantages of TVMD control compared with conventional viscous dampers.