Effects of Mathematical Model of MR Damper on Its Control Performance; A Nonlinear Comparative Study

In this paper, the effect of mathematical representation method of an MR damper on the performance of control algorithm is investigated. The most exact and common Maxwel Nonlinear Slider (MNS) and modified Bouc-Wen hysteretic models are employed through a nonlinear comparatve numerical study. In many of semi-active control algorithms, a mathematical modelling method is required for determinig the Magneto-Rheological (MR) damper voltage at each time instant. Using different modelling methods can lead to different voltages for the MR damper, which subsequently results in changes to the responses of the controlled structure. A three story office building steel structure is excited by seven acceleration time histories. Nonlinear instantaneous optimal control (NIOC) and linear quadratic regulator (LQR) controllers are utilized as two active-based semi-active algorithms. Results of nonlinear investigations show an obvious difference between the MNS and the modified Bouc-Wen models in the performance of control algorithms. Outputs show a higher performance for the modified Bouc-Wen model in reducing the hysteretic energy in the structure.