Seismic Performance Analysis Of Subway Stations Considering Randomness Of Ground Motion And Soil Parameters

At the present stage,the seismic performance analysis of subway stations is constantly evolving and maturing.Further considering the influence of non-stationary ground motion and randomness of soil layer parameters,it becomes one of the new research questions to evaluate the seismic reliability of station structures based on the results of random response analysis.On this basis,this article considers the randomness of ground motion and soil parameters around the structure to calculate the random response of subway station structure under earthquake and analyze its seismic performance.Firstly,using ABAQUS finite element software,a two-story double-column and three-span island subway station is taken as the research object,and the overall finite element model of soil-subway station structure is established,and the structural dynamic characteristics are analyzed.The structural stress and deformation response are calculated by using a typical artificial ground motion as the seismic input at the bottom of the soil layer.Then,according to the ground motion evolution power spectrum model,the spectral representation method is used to generate 200 random ground motion time-history samples with different intensity and waveform.At the same time,it is assumed that the soil shear wave velocity obeys log-normal distribution and simulates 200 sets of soil layer combination samples.Based on the ground motion and soil layer simulation results,the seismic response analysis of the soil-subway station structure finite element model is carried out.The deformation displacement of the structural layer,the stresses at the bottoms of the walls and the columns have been calculated by using the probability density evolution method,and the response probability density evolution map is obtained.Finally,based on the random response simulation results,and assuming that the response extremes are log-normal distribution,the distributions of the interlayer displacement of the subway station and the stress at the bottoms of the walls and the columns are obtained.According to the extreme responses,the seismic safety of the station structure is evaluated.The research results in this article can provide reference for seismic design of urban subway stations.