Experimental research on mechanical behavior and seismic response reduction of MR damper

The force-displacement and force-velocity curves of MR damper at different frequencies,amplitudes and input currents were obtained by the mechanical behavior test of RD1097 type MR damper.Furthermore,an improved arc tangent function nonlinear model of MR damper was put forward,and the seismic response reduction test of the above type MR damper under the sine wave and El-Centro wave was implemented.The results show that the improved MR damper mechanical model has the characteristics of less identifiable parameters,programming conveniently and high precision,and it can not only describe the relationship between the damping force and displacement precisely,but also simulate frictional lagging effect well.It is very effective for the model to simulate the damping force during invariant frequency vibration and random seismic waves.The structure response with MR damper can be evidently controlled.With the excitation of the El-Centro wave,the peak and its average square root of the displacement response with MR damper decrease by 62.75% and 77.17%,respectively.