Design, performance test and analysis on magnetorheological damper for earthquake mitigation

Abstract

As a semi-active control device, magnetorheological (MR) dampers have been paid more attention because of their high controllability, fast response and low power requirement. When MR dampers are used for vibration mitigation, some challenge topics must be taken into account, such as design method, performance study and intelligent control algorithm. In this paper, a detailed design process of MR damper involving the geometry design and magnetic circuit design is carried out, and a multistage shear-valve mode MR damper is designed and manufactured. Then the MR damper is tested to investigate the influence of control current, displacement amplitude and excitation frequency on the damper's mechanical behavior and energy dissipation performance. At the same time, the design target values are compared with experimental results. Comparison results show that the proposed design method holds promise in designing and optimizing the MR damper. Finally, a modified Sigmoid model is proposed. Comparison results between the experimental data and the numerical data indicate that the modified Sigmoid model can accurately describe the behaviors of the MR damper.

Using a limited set of MR dampers for improving structural seismic response

“…In the frame of this study, updating the properties of MR dampers was carried out using the design procedure proposed by Xu et al . .…”

“…Aguirre et al [26] have demonstrated that the forces predicted using the viscous + Dahl model were in good agreement with experimental results. Xu et al [18] have reported that a modified sigmoid model accurately describes the behaviors of MR devices. In the frame of this study, updating the properties of MR dampers was carried out using the design procedure proposed by Xu et al [18].…”

“…Magnetorheological dampers have high controllability, fast response, and low power requirements. A detailed design procedure for MR dampers was described by Xu et al [18]. A multistage shear-valve mode MR damper was designed, manufactured, and tested, to compare the design target values with experimental results.…”

Identification of Sudden Stiffness Change in the Acceleration Response of a Nonlinear Hysteretic Structure

“…As a result, it is difficult to accurately identify the damping coefficients. e second reason is that, as presented in Reference [27], the abruptness parameter in the classical Bouc-Wen model (n) is a power factor, which changes the smoothness of transition from elastic region to plastic region in the hysteretic versus actual displacement curves, with little change in the acceleration response. Correspondingly, the remaining three parameters in the classical Bouc-Wen model are not sensitive to accelerations.…”

Semiactive control for a distributed mass damper system

“…With the capability of adjusting their behavior to the responses of the structure, smart controllable semiactive dampers can effectively reduce vibration [15][16][17][18][19][20]. Controllable fluid dampers [21], such as magnetorheological (MR) fluid dampers [22,23], use less energy than fully active devices, such as hydraulic actuators, so they can operate on batteries and, therefore, are robust to losses in external power. In this paper, the semiactive control of the DMD system will be studied using a proposed gain scheduling strategy for controllable dampers in comparison with the well-known clipped-optimal strategy for semiactive dampers [15] and a passively-damped design.…”