Seismic Analysis and Research of Nanning Metro Station Structure through Water-rich Sand Stratum

Abstract

After the Great Hanshin Earthquake, the engineering community began to pay attention to the research on the seismic safety of underground structures. A subway station in Nanning, Guangxi is located in a water-rich sand layer. Combining with Nanning's seismic fortification intensity, a variety of seismic design analysis methods are used to study the response law of the two-story frame structure of the underground station under the action of seismic forces. The results show that: (1) The one-dimensional free-field analysis method and the three-dimensional equivalent linear time history analysis method calculate that the relative displacements of the station roof and floor are basically the same, and both decrease with the increase of depth. (2) The bending moment calculated by the three-dimensional equivalent linear time history analysis method and the reaction displacement method is basically the same as the maximum position of the axial force, but the values are different, and the internal force and bending moment at the connection between the station center column and each floor Significantly larger than the surrounding area. (3) Using the three-dimensional equivalent linear time history analysis method, the maximum value of the relative displacement of the station structure is 162.2mm, and when using the reaction displacement method, the maximum value is 90.6mm, and they all occur on the roof of the station.