Isolation And Torsion Effect Analysis Of Irregular Base Isolation Structure

With traditional seismic system is not the same, it is an isolated structure by setting the seismic isolation device to absorb earthquake energy consumption,reducing the seismic response of structures to ensure the structural safety of a passive control system. Preclude the use of isolation technology, due to the horizontal stiffness of the isolation layer structure relative to the upper level low stiffness in the earthquake, the isolation layer will undergo significant horizontal displacement, while the upper structure is almost flat as a whole move. With the development of urban architecture appears more and more irregular structure, these irregularities also appear to reverse the effects under the earthquake.This paper describes the earthquake disaster serious harm to society,highlighting the need for building damping, it leads to the emergence of building isolation techniques and a general description of the history of architecture and design overview isolation isolation, followed by paper tandem particle isolated structure model and isolated torsion calculation model made brief derived differential equations of motion of both models and briefly described. Analysis software SAP2000 structure nonlinear dynamic finite element analysis process, a five-layer structure of a multilayer frame structure as an example, with respect to the isolated structure under earthquake conventional seismic structure and reduce torsional damping effect. After reversing the effects of factors affecting the isolated structure to do a detailed analysis, by changing the isolation layer isolation bearings arranged to change the stiffness of the eccentricity of the isolation layer, in order to analyze the stiffness of the isolation layer eccentricity of isolation effects of reversing the structure under seismic action; by changing the level of torsional stiffness of the isolation structure of the upper structure member to change the floor stiffness eccentricity of the upper structure, in order to analyze the impact of isolated structures superstructure floors eccentricity of torsion Effect; with a representative of the top and bottom floors for the study analyzed the isolation layer eccentricity and eccentricity of the upper structure interaction on isolated structure; by changing the isolation layer bearing arranged to change the horizontal stiffness of the isolation layer order analysis of isolated structure isolation layer horizontal stiffness on torsion effect of isolated structure.The results showed that the isolated structure with respect to the non-seismic isolation structure under horizontal earthquake earthquake not only greatly reduce the reverse effect is also significantly reduced, and the isolation layer eccentricity,the eccentricity of the upper structure, the isolation layer horizontal stiffness there are varying degrees of influence on the isolated structure reverse effect. This paper considers not only the single-factor structure torsion effect, also takes into account the interaction of multiple factors influence the structure of reverse effect, better practical engineering application. According to the analysis, the practical engineering application of the proper control of these factors can effectively reverse the effects of control structures.