Full-scale real-time testing and analysis of a viscoelastically-damped steel frame

An experimental and analytical investigation of a full-scale frame with viscoelastic (VE-) dampers was conducted. All tests were conducted in real-time due to the velocity sensitive properties of the VE-material. Harmonic, seismic, and wind forces were considered.; A methodology was developed to test the full-scale lower three story portion of a 10-story prototype frame. The methodology employs time history analysis of the 10-story VE-frame, with a fractional derivative model for the VE-damper behavior, to determine the imposed displacement history at the third story level of the test specimen.; A seismic prototype frame was developed to permit investigation of the earthquake response for a VE-damped frame. The VE-frame exhibited frequency, temperature, and amplitude sensitivities typical of the VE-material. Damping ratio for the frame was relatively stable, while the frame stiffness was highly dependent on damper temperature. Experiments provided comprehensive data including overall frame and local member and connection responses and indicated elastic member response for the different earthquakes considered. Correlative analyses were performed which reasonably predicted the seismic response for typical short duration earthquakes using several models for the VE-damper including: fractional derivative, global Rayleigh damping, and local Rayleigh damping models.; A wind prototype frame was developed to permit investigation of the along-wind and across-wind response for a VE-damped frame. Long duration wind experiments indicated heat convection between the damper and environment should be considered. Analyses indicated the VE-dampers significantly reduced the natural frequency vibration which would otherwise be induced by wind gusts.