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Earthquake Simulator Testing and Analytical Studies of Two Energy-Absorbing Systems for Multistory Structures.
Aiken, I. D.; Kelly, J. M.
National Science Foundation, Washington, DC.; Sumitomo Metal Industries Ltd., Osaka (Japan)., October 1990, 294 p.
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The study used two different types of energy-absorbing devices to improve the seismic behavior of a large-scale, multistory steel frame building: a viscoelastic shear damper designed using an energy approach, and a friction device with almost perfectly rectangular hysteresis behavior for which an iterative nonlinear analysis design method was adopted. A 9-story, moment-resisting steel frame representing the basic structure of the study was tested with both types of energy absorbers installed and also in moment-resisting and concentrically-braced configurations. The large number of tests permitted numerous comparisons of the four structural systems. The damped structures were found to have base shears similar to the moment-resisting frame while reducing drifts to the level of those of the concentrically-braced frame. Analytical methods suitable for predicting the response of the two damped structures were studied. A linear analysis incorporating damping on a modal basis produced very good results for the viscoelastically-damped system. Furthermore, the use of linear elastic response spectra with high damping gave good results for story shears and displacements. A nonlinear analysis of the friction-damped structure was necessary to predict the response accurately.
; Energy absorption; Earthquake resistant structures; Structural vibration; Steel structures; Test facilities; Mathematical models; Model tests; Dynamic response; Earthquake engineering; Vibration damping; Vibration isolators