Energy dissipation demand and distribution for multi-story buildings with fluid viscous dampers

Abstract

The seismic response of structures with fluid viscous dampers (FVDs), which is a predominant type of structural control techniques, can be analysed from the perspective of energy. In such structures, the imposed seismic energy is mainly dissipated by the structural plastic energy, EP, and the energy dissipated by FVDs, Ed2, which quantify the structural cumulative damage and FVD’s seismic reduction effect, respectively. Research conducted in the past focuses on investigating the EP demand of systems without supplemental damping devices, but little knowledge is available for the EP and Ed2 demand in multi-story buildings equipped with FVDs. To fill this gap, this paper conducted a comprehensive investigation based on four steel-moment resisting buildings with different height (3-, 6-, 9-, and 20-stories, respectively) equipped with linear or nonlinear FVDs. The effect of structural property and FVDs properties, characterised by the supplemental damping ratio ξadd and velocity power α, on the EP and Ed2‘s overall demand and distributions among stories were illustrated. The results indicate coupling effects of structural property, ξadd and α, on the EP and Ed2 demands. In most cases, the increase of ξadd and the decrease of α can reduce the EP demand and increase the Ed2 response. However, the increasing of ξadd is not effective if it is larger than 20% and the FVDs with α = 0.3 are not recommended in relative high-rise buildings. The distribution pattern shows a trend of linearly decreasing along the height, but those in the high-rise buildings are disturbed by high-mode effects.