SEISMIC BEHAVIOR OF STEEL FRAME WITH ADDED VISCOELASTIC DAMPERS

This paper describes the results of an extensive study on the seismic behavior of a viscoelastically damped structure under mild and strong earthquake ground motions, Shaking-table studies were conducted on a 2 /5-scale five-story steel model with added viscoelastic (VE) dampers u nder various ambient temperatures, damper-placement cases, and earthqu ake intensities. Three types of VE dampers distinguished by dimensions and viscoelastic materials designed to provide the structure with sim ilar damping ratios at room temperature were used. Analytical studies were carried out to predict the equivalent damping ratios and seismic response of the viscoelastically damped structure. Experimental result s show that the VE dampers are effective in attenuating seismic struct ural response under mild and strong earthquake ground motions. Numeric al results show that the structural damping and structural response wi th added VE dampers can be easily and accurately calculated by the pro posed analytical methods. The methods are readily available to practic al applications.