Analytical Method and Its Experimental Verification for Seismic Reduction of Story-Increased Structures Under Earthquake

Structural passive control devices have widely used in various engineering projects for resisting the wind load or earthquake excitation until now. The friction damper and sand isolation technology among them are of many advantages, such as easy installation, less cost and less maintenance fee. In this paper, a new type of energy-dissipated structural system for the reconstructive building with the story-increased frame is presented and investigated, in which the sliding-friction layer with sand between the lowest increased floor of outer frame structure and roof of original building is applied, and friction energy-dissipated dampers are used for the connections between the columns of outer frame and each floor of original building. A simplified analytical model of this system is proposed. For more appropriate theoretical analysis, the non-classical damping approach is introduced to calculation. The shaking table test is performed on the model of system to verify the effectiveness of the above seismic reduction system and proposed method. The results show that friction and energy-dissipated devices are very effective in reducing the seismic response and dissipating the input energy of model structure.