Abstract
A semi-active stiffness damper has been shown to be effective in reducing structural responses against earthquake forces. This system uses a MR (magnetorheological) damper as a control device connected to the bracing frame. In order to take advantage of MR damper, a model must be developed to characterize the damper's nonlinear behavior. An experimental test has been conducted to obtain the data necessary for modelling MR damper through parametric identification. Simple and modified Bouc-Wen models are considered for modelling hysteretic systems. The response analysis results show that both models are effective in predicting the response of the MR damper.
