双磁场控制的磁流变减震结构振动台试验研究

Shaking table test on a magnetorheological damping structure controlled by dual magnetic fields

摘要:

传统磁流变减隔振器通常由线圈持续供电,不仅增大耗能,也会减少器件的使用寿命。基于磁流变凝胶(MRG)的剪切工作原理,运用剪切型结构设计一种新型磁流变凝胶减震装置，采用永磁体和线圈共同控制磁场大小和方向,通过改变磁流变凝胶的磁化程度实现阻尼力大小的控制。将该装置安装在一2层钢框架结构模型的底层,采用恒定电流控制法开展磁流变减震结构振动台试验研究,分析不同电流下减震结构系统对不同地震波的振动控制效果。试验结果表明:该磁流变凝胶减震装置能够显著降低结构的动力响应,对于不同的地震波其减震效果有所差异,随着峰值加速度的增加其减震效果有所下降。

Abstract:

Conventional magnetorheological dampers are usually powered continuously by coils, which not only increase energy consumption but also reduce the service life of a device. Based on the shearing principle of magnetorheological gel (MRG), a novel shearing magnetorheological gel damping device was designed in this paper. The permanent magnets and coils were used to jointly control the magnitude and direction of the device's magnetic field, and the damping force magnitude was controlled by changing the magnetization level of MRG. The device was installed at the bottom floor of a two-story steel frame-structure model, and the shaking table test of the magnetorheological damping structure was carried out using the constant current control method. The control effects of the damping system on different seismic waves under different currents were analyzed. Results show that the MRG damping device can significantly reduce the dynamic response of the structure; the damping effect varies for different seismic waves, and the damping effect decreases with increasing peak acceleration.