黏滞阻尼器层间隔震结构振动台试验研究

Shaking Table Test Study on Mid-story Isolation Structures with Viscous Dampers

层间隔震结构是基础隔震结构的发展与延伸,作为一种复杂结构体系,基础隔震结构的工作机理不一定完全适合,延长结构的周期可能无法同时降低上、下部结构的地震响应。此类体系以往的理论及试验研究,隔震层的阻尼多由铅芯橡胶支座提供,采用天然橡胶支座及黏滞阻尼器作为隔震层,进行了层间隔震结构振动台试验研究。设计了一个4层的钢框架模型,依次进行了基础固接、基础隔震、1层顶隔震、2层顶隔震及3层顶隔震的振动台试验研究,测定结构的加速度、层间位移及层剪力系数。试验结果表明:黏滞阻尼器层间隔震结构具有良好的减震效果。建立了层间隔震结构的有限元模型,将有限元分析结果与试验结果进行了对比。

Mid-story isolation structure is developing from base isolation structures. As a complex structural system, the work mechanism of base isolation structure is not entirely appropriate for mid-story isolation structure, and the prolonging of structural natural period may not be able to decrease the seismic response of substructure and superstructure simultaneously. In the previous theoretical and experimental studies, the damping of isolation layer was mostly provided by lead rubber bearings. In this paper, using natural rubber bearings and viscous dampers as the isolation layer, the shaking table test for a mid-story isolation structure was conducted. For a four-story steel frame model, the locations of isolation layer are set at bottom of the first story, top of the first story, top of the second story or top of the third story in turn. Changing the location of isolation layer, acceleration, story displacement and story shear force coefficient were measured. The results show that mid-story isolation with viscous dampers has a good seismic reduction effectiveness.The finite element model of a mid-story isolation system was established, and the comparison between the finite element analysis results and test results was conducted.