设置黏滞阻尼器的悬挂减振结构振动台试验研究

Shaking table experiment of vibration-controlling suspended-floor structure equipped with viscous dampers

通过对设置黏滞流体阻尼器的悬挂结构进行地震模拟振动台试验,分析了主结构与悬挂楼面的质量比、连接方式以及阻尼器分布对悬挂结构模型的频率、阻尼比和结构响应的影响。试验结果表明:与刚性杆连接的常规悬挂结构相比,采用阻尼器连接主结构和悬挂楼面,可改变结构频率,提高结构振型阻尼比,且模型前3阶振型主要表现为悬挂楼面剪切变形;悬挂减振结构主结构的位移峰值响应小于常规悬挂结构,略小于无连接的自由悬挂结构;当悬挂楼段质量较大时,减振效果更好;与自由悬挂结构相比,阻尼器连接的悬挂减振结构能较好地抑制悬挂楼面相对于主结构的位移和悬挂楼面的层间位移;当悬挂楼面侧向刚度较小时,阻尼器均匀布置比集中布置能更好地控制悬挂楼面的相对位移。

A shaking table experiment of suspended-floor structures equipped with fluid viscous dampers has been conducted in this paper. The effects of link types and the mass ratios between the primary structure and suspended floors and distribution patterns of dampers on responses of suspended-floor structure models were verified. These responses included the frequency, the mode-damping and maximum displacements of suspended-floor structures. Test results show that the frequencies and the mode damping adjusted and the first three modes are mainly influenced by suspended-floor structures with rigid-bar links. Maximum of suspended-floor structures installed with dampers are the shear drift of suspended floors compared with traditional displacements of the primary structure＇s top floor of the suspended-floor structure with dampers are smaller than the traditional suspended-floor structure and slightly smaller than the free suspended-floor structure without links. Moreover, the relative larger mass of the suspended segment is helpful to control the primary structure＇ s dynamic responses. Besides, suspended-floor structures with dampers can effectively control the displacement of suspended floors relative to the primary structure and story drifts of suspended floors compared with free suspended-floor structures. When the lateral stiffness of suspended floors is relatively little, the uniform distribution of dampers is more effective to control the relative displacements of suspended floors than the congregating distribution of dampers.