Research On Key Technologies Of Rubber Bearing Base Isolation Design In Shear Wall Structures

Isolation structure refers to setting an isolation layer, which is made up of rubber bearing, damping device and other components and has the overall reset function, between the superstructure and the substructure. In this way, the expected seismic fortification requirements can be satisfied with prolonged natural vibration period of the whole structural system and lessened horizontal earthquake actions inputted into the superstructure. Isolation system is under rapid development in recent years. It has attracted extensive attention from investors and engineers due to its significant advantages in the aspects of improving seismic safety and so on.In this thesis, a high-rise shear wall structure is taken as the research object; and its isolation effects and seismic response characteristics after using the base isolation technology are investigated. The building structure analysis and design software ETABS developed by the American CSI company is utilized to simulate the isolation bearing; and the three-dimensional finite element analysis software SATWE, based on shell element theory and developed by China Academy of Building Research, serves as the supplementary analysis software. A detailed analysis of damping coefficient and linear and non-linear analysis of each working condition and each phase are conducted in this research. Conclusions about key technologies of the seismic isolation design are drawn through comparisons of a large amount of analysis and calculations.Laminated rubber bearing is modeled by biaxial hysteretic nonlinear element. This element possesses the coupled plastic properties for two shear deformations and the linear effective stiffness properties for the other four deformations. For each shear deformation degree, it can be specified as linear or nonlinear behavior independently. However, for axial deformation and three bending deformations, their properties are linear.The evaluation analysis of seismic isolation effects on structures in this thesis has provided the conceptual support for seismic isolation design. The seismic response of isolation structures is 1/25～1/9 of traditional structures, which is equal to a decrease of 3～5.5 degrees in seismic intensity. Therefore, it is suggested that isolation structures be designed as 2 degrees lower.Isolation design is nowadays a highbrow field with vast scientific research achievements, but few design companies at the forefront are able to undertake the design and optimization work. Therefore, this paper integrates the isolation design into traditional design methods by taking practical engineering project, concentrating on isolation design and demonstrating specified design details.