Seismic Upgrade of an Existing Tall Building Using Different Supplemental Energy Dissipation Devices

Abstract

The feasibility and cost-effectiveness of various retrofit techniques to improve the seismic performance of an existing 35-story steel building are examined. Three types of supplemental energy dissipation devices are used in conjunction with basic retrofit measures to achieve the collapse prevention performance objective of current standards. Devices considered include fluid viscous dampers (FVDs), viscous wall dampers, and buckling restrained braces. The placement of the devices was kept the same in all three cases, considering overall architectural, programmatic, and constructability issues. The mechanical characteristics of the devices were selected using a simplified approach to achieve the same overall effective damping ratios and story drifts consistent with the targeted collapse prevention performance objective. The results of nonlinear dynamic analyses indicate that the FVD scheme was the most efficient for this structure in achieving the targeted performance goal and provided the most cost-effective means of improving the structural behavior and reducing economic losses for Level 2 basic safety earthquake hazard events. Future research needs related to the use of supplemental energy dissipation devices in existing buildings are also discussed.