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 under various ambient temperatures, damper-placement cases, and earthquake intensities. Three types of VE dampers distinguished by dimensions and viscoelastic materials designed to provide the structure with similar 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 results show that the VE dampers are effective in attenuating seismic structural response under mild and strong earthquake ground motions. Numerical results show that the structural damping and structural response with added VE dampers can be easily and accurately calculated by the proposed analytical methods. The methods are readily available to practical applications.