The Performance Analysis Of The Frame Structures With Seismic Isolation Device

Building isolation is an isolation technology which usually sets up an isolation device at the bottom of structures or between layers of the upper floors. Building isolated structure system is a passive control system which is different from the traditional anti-seismic structure, and it can absorb the seismic energy input and consumption through the isolation layer of the isolation bearings to reduce the structural seismic response of the earthquake. With the development and improvement of the isolation technology, it brings new ideas and methods to the field of earthquake disaster reduction for the engineering development. The isolation technology is divided into base isolation and story isolation. With the deep research of the base isolation technology, it has formed a complete set of theory and has been widely used in the actual project. However, the story isolation technology is still in constant development and improvement, and the mechanism of the story isolation and its differences to earthquake base-isolation of the damping effect is not clear. Based on this point, through the theoretical derivation and numerical simulation analysis of the shock damping effect of base isolation and story isolation, and by comparing with the traditional anti-seismic structure, this thesis makes a comparative study of the similarities and differences of the two in the frame structure of the isolation performance, ,This paper begins with describing the isolation bearings of the mechanical properties and the mechanical model of earthquake base-isolation and story isolation as well as the establishment of dynamic equilibrium equation, and then derives the solution to the dynamic equilibrium equations of the isolation system, and then we use the large-scale structural finite element analysis software SAP2000 to make a dynamic time-history analysis of the on base isolation and the isolation layer and placed on three layers of eight-story-lifting frame interval of shock 7 degrees in the Han case of EL-Centro wave, wave in Tangshan, Nanjing and waves carried out under. And then we make a comparative study of the calculation results with the traditional anti-seismic frame structure to evaluate the vibration isolation structure between the damping effect and the damping law. At the same time, the author analyzed the impact of the change of isolated structural parameters to the structural dynamic response, and he also analyzed the isolated structure derived height-width ratio in order to provide references to the selection of the isolated rational design optimization parameters and base-isolated structure.The research results show that base isolation and story isolation have a very significant shock damping effect and the location of the level of isolation story isolation have a greater impact on the layer of shock effects and shock absorber damping mechanisms. Meanwhile, acceleration of the upper structure and lower of the shock-layer structure interval, the floor displacement and shear have different trends. When the position of isolation layer is high, the isolation mechanism is similar to the TMD system, and when it is low, it is similar to the base-isolation, and the isolation of different parameters of the structure of the dynamic response will produce certain impact.