Improvement of Configuration and Corresponding Design Formulation for Viscous Dampers in Taiwan

Improvement of Configuration and Corresponding Design Formulation for Viscous Dampers in Taiwan

The configurations for viscous dampers implemented in seismic design and retrofitting for buildings worldwide include diagonal-braced, K-braced, and toggle-braced damper systems. In recent practical applications in Taiwan, a few new viscous damper configurations have been adopted for the purposes of increasing flexibility of space accommodation and/or architectural lighting considerations in order to meet the requirements of architects and engineers. The purpose of this study is to investigate how the new viscous damper configurations affect the energy dissipation abilities of building structures, such as the flexibility of connected beams. Based on the results of numerical analysis performed on a model of a five-story frame with the new damper configurations implemented, it is found that they cannot achieve the desired damping ratio. Therefore, this study proposes a configuration with vertical linkages to the viscous damper to reduce the flexibility of the connected beams. In addition, design formulas are derived considering the mode shape of the building with the vertical linkages. The analysis results indicate that vertical linkages installed at the midspan of the beam will provide a sufficient damping ratio as expected.