Seismic Dynamic History Analysis Of Subway Station With Single-Double Column Structure

In recent years, the earthquake disaster has happened frequently in China, in order to reduce the damage and losses, the best way is to do the structure of the seismic, although the seismic performance of the underground structure is considered to be stronger than that of the ground structure, but according to the previous earthquake disaster data, the earthquake damage of underground structure is destructive. Therefore, we must pay attention to the seismic design of underground structures, subway as an important means to solve the urban traffic, China has entered a rapid development period, but so far, there is still a lack of independent and perfect subway underground structure seismic design code, how to ensure the safety of the subway in the earthquake has become an urgent need to study the subject.This paper takes the Qingdao subway(Liang he station)as the research object, based on MIDAS finite element software, a three-dimensional finite element model was established of the variable section, analyzed the dynamic response of subway station with variable cross section, it has important theoretical significance and engineering value. The main contents of this paper are:(1) The existing methods of seismic analysis were introduced, the basic theory of finite element were analyzed, based on MIDAS,a three-dimensional finite element model was established of the variable section, the viscoelastic artificial boundary and Elentro seismic wave were selected to carried out the seismic numerical simulation and the dynamic response of subway station with variable section were analyzed.(2) The displacement and stress distribution in the horizontal and vertical seismic waves at the station and under the action of the single action and the common action are compared and analyzed, the weak position of the column structure was found by analyzing. Finally, it is concluded that the horizontal seismic wave plays an important role in the structure, although the vertical seismic wave can increase the internal force and displacement of the structure, the increase is limited.(3) Under the action of earthquake,by arranging the measuring line and measuring point analyzed the change rule of the stress and displacement of the top plate, the column and the side wall in the length direction of the variable station along with the water level. Under the condition of high water level, the maximum shear stress of roof has a funnel-shaped distribution, due to the change of the structure section, the center of roof has a large stress concentration and the relative displacement of the roof is larger in the single column structure, with the extension of the structure, the displacement of the double column section is reduced.(4) The seismic response characteristics of the station under the condition of different single surrounding rock are compared and analyzed. The overall displacement and maximum shear stress of the whole station under the condition of single hard surrounding rock is small, and the displacement and maximum shear stress distribution of the whole station is different from that of the non-single layer.