Shaking table tests for a mid-story isolation structure with shock absorbers

Mid-story isolation structure is a development and extension of base isolation structures. Previous studied focused on the effect of parameters of isolation layer on earthquake response and seismic reduction effectiveness. Here, shaking table tests for a mid-story isolation structure with shock absorbers on substructure were conducted. For a four-story steel frame model, the cases of its base fixed and its first story top isolated were firstly tested; secondly, viscous dampers were added on substructure and a shaking table test was done. Acceleration, story displacement and story shear force coefficient were measured respectively. It was shown that based on the case of the top of the first story isolated, adding shock absorbers on substructure can improve 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 ones was conducted.