Research On Seismic Isolation Design Method Of Long Span High-speed Rail Station In High Seismic Intensity Region

Large spans and high-speed rail station in high seismic intensity region is a lifeline project,which characterized by large volume,large span,high headroom,complex ground and underground structural forms.Thus,Seismic fortificated is difficult in the structure.Traditional seismic design methods or single structural vibration control techniques may be difficult to achieve the excepted of anti-seismic requirements.It is necessary to apply the combinated vibration control techniques with better vibration control effect to the structures.In this paper,a combination of theoretical analysis,numerical simulation,and engineering examples is used to conduct a systematic study on the large-span and high-spead rail station,which uses seismic isolation combined with energy-dissipation technology.Based on the energy dissipation design and seismic isolation design,according to the different locations of seismic isolation layers and the calculation of damping coefficients,two different types of combinatorial design process are proposed: energy dissipate first combinatorial design process or seismic isolation design first combinatorial design process.Based on the simplified model and assumptions,through the derivation of formula,the theoretical calculation formula of damping coefficient in combinatorial design process is proposed,then study the influence of relevant parameters in the calculation formula on the combinatorial design.The research results show that the latger ratio of the site period to the period of combinated vibration control structure,the more obvious the seismic damping effect in the combinated vibration control structure.Reduce the stiffness of the isolation layer,increase the self-vibration period of the seismic isolation structure,and help improve the seismic performance of the structure.Establish a finite element analysis model of rail station,verify the feasibility of the combination design process and the accuracy of the calculation formula damping coefficients through numerical simulation analysis.By comparing the damping effect and design steps of different types in combinatorial design process,from the perspective of safety and convenience,it is recommended to rail station adopt the seismic isolation design first combinatorial design process.Research on the location of seismic isolation layer of rail station and the technical difficulties.Propose two technical solutions to solve the problem that the traditional rail transit system crosses the vertical isolation joints and hinder the free movement of the upper structures when the earthquake occurs in the earthquake-isolated station structure,which hinders the free movement of the seismic isololation layer.Propose the measures for the seismic performance of the substructure with the layer isolation,solve the problem in the seismic design of the substructure with the layer isolation.Research to solve the problem of horizontal displacement control of the seismic isolation layer of rail station.Propose a relatively complete seismic isolation combined with energy-dissipation technology method suitable for Large spans and high-speed rail station in high seismic intensity region,and use the actual rail station to combinatorial design.The design results show that the combinatorial design can significantly improve the seismic performance of the upper structure seismic isolation layer,and the lower structure of the seismic isolation layer can effectively control the deformation through energy dissipation design.The high-speed rail station can achieve expected goal of seismic protection.