斜拉索采用MR阻尼器半主动控制的研究

Semi - active control strategy of stay - cable vibration using MR dampers

采用基于位移和速度方向的半主动控制算法,对斜拉索和MR阻尼器组成的系统进行动力分析,考察了 斜拉索基频(张力、索长、质量)、Irvine参数、激励荷载(类型、频率、大小)等各种因素对斜拉索动力响应的影 响,并与MR阻尼器被动控制效果进行了比较,以全索全时段振动响应的均方根作为振动控制效果的评价指 标．研究表明,MR阻尼器半主动控制对斜拉索抑振效果比MR阻尼器被动控制有较大幅度的提高．位移RMS 减小的幅度可达50％,且在MR阻尼器型号的有效区间内可使多阶振动模态均取得较好的减振效果．

A stay cable incorporated with MR dampers exhibits pronounced nonlinearity. The dynamic response performances of a cable with MR dampers are explored in detail using Spencer photometric model . The primary measure of damper performance considered is the root mean square (RMS) cable deflection integrated along the length of the cable and the whole time. The relationship of the optimal marker of MR dampers, mounting postion, voltage applied, the first frequency of cables (tensile force, length and mass perunit length), excited loads (type, frequency and amount) were studied. The semi - active control strategy of cable vibration is provided based on the direction of both displacement and velocity. The comparison study among the semi - active under the strategy, the optimal passive MR damper, indicated the advantages of semi - active dynamic adjust control with a better control performance when MR dampers marker is within the effective region. The strategy is robust and quite easy to be applied for fewer sensors is need. The dynamic range of MR dampers are sufficiently wide. MR dampers can be more effective in first three frequency modes than oil dampers do.