Numerical Models and Seismic Design of Steel Frames Equipped with Supplemental Fluid Viscous Devices

Abstract

Numerical investigations were conducted to assess the seismic performance of steel frames equipped with supplemental viscous damper devices. The study was based on experimental results of pseudo-dynamic tests carried out on a prototype steel frame at the JRC Ispra. A finite element assembly reproducing the observed behaviour of fluid viscous devices was developed and implemented in numerical models of multi-story steel frames. An energy based design procedure was applied to determine the damping properties of the devices and the seismic response of two multi-story steel frames was investigated. Comparison of the seismic response of the frames with and without viscous dampers indicated that the application of this innovative technique is very effective in attenuating the effects of seismic actions on structures. The effectiveness of the damper braces was also evaluated through a comparison with a traditional undamped bracing solution. The frames protected with fluid viscous devices exhibited smaller interstory drifts compared to the unprotected frames and smaller story shear forces compared to frames with traditional bracing system due to the energy dissipation provided by the fluid viscous devices.