Analysis Of Seismic Response And Isolation Effect Of Single Column And Double Span Metro Station

The rapid development of Metro based urban rail transit alleviates traffic congestion in large and medium-sized cities.In recent years,the single column double span subway station with high passenger flow efficiency and wide field of vision is widely used in many cities.The foundation soil layer will deform under the excitation of earthquake.The weak part of the structure is damaged due to soil deformation,which affects the safety of the whole underground structure system.Many scholars at home and abroad realize that the aseismic problem of underground structure cannot be ignored.Increasing the section and improving the ductility of the structure are the traditional structural measures to improve the seismic performance of the structure.Spatial performance of the structure is affected by seismic structural measures.It is difficult to repair the structure under strong earthquake,which brings economic loss to human beings.Because of the above two reasons,the scope of application of traditional seismic structural measures is affected.It is urgent to find a new seismic design method.Isolation method with high economy and applicability becomes the first choice.Isolation bearing can effectively reduce the seismic action of the upper structure,and the underground structure can continue to use only by replacing the isolation bearing after the earthquake damage.In this paper,based on the concept of the ground buildings isolation,the dynamic interaction model of single-column and double-span subway station was established by MIDAS-GTS using numerical simulation method,which is taking the structural form of subway station,the location of isolation bearing and relevant parameters as variables.Main conclusions of the paper are as follows:1)The larger the span of the station is,the more significant the seismic response is.2)The vibration characteristic of seismic wave is closer to the natural vibration period of structure,the dynamic response of the structure is more obvious.3)The isolation effect is the best when the isolation bearing is set on the top of the upper middle column.4)The correlation between the internal force of the station structure and the horizontal stiffness of the support is stronger,and the correlation between the displacement difference and the damping coefficient of the support is stronger.In order to meet the economic safety,the bearing with horizontal stiffness of 2247-2746 kN/m and damping coefficient of 3200-4800 kN/(m·s^-1)shall be selected as far as possible.