Seismic Demand on Acceleration-Sensitive Nonstructural Components in Viscously Damped Braced Frames

Abstract

This paper investigates the seismic demand on acceleration-sensitive nonstructural components in buildings equipped with fluid viscous dampers. Nonlinear dynamic response analyses were conducted on three steel moment-resisting archetype frames of different heights, and incorporating linear and nonlinear viscously damped braces. The FEMA P695 far-field ground motion records set scaled to various intensities were used as seismic input. The main variables investigated in the parametric study included three different target supplemental damping levels, two different distributions of damper properties along the frames’ height, and six different nonlinear damper velocity exponents. The numerical results indicate that the inclusion of fluid viscous dampers generally improves the seismic response of the archetype frames. However, the seismic demand on acceleration-sensitive nonstructural components varies significantly depending on the properties of the dampers. For some combinations of dampers’ properties, the peak floor horizontal accelerations and floor spectral absolute accelerations in certain nonstructural period ranges can exceed that of the control frames without fluid viscous dampers. These results highlight the limitations of the peak floor acceleration as an engineering demand parameter for acceleration-sensitive nonstructural components.