Experiment Aided Numerical Simulation Study On Long-span Prestressed Station Structures Of Metro Station

This project will carry out static and dynamic time history analysis for a new long-span prestressed subway station.Name of this project: 2015BAK14B02.The subway station plays the role of the traffic hub in the subway line,which can effectively help the passenger flow on the ground and the underground,and has the function of conveying the passenger flow quickly.The subway stations we usually see are mostly double and three-span column structure.The distance between the columns of the traditional subway station is between 5~10m on the platform level.The existence of columns is the basis for the realization of traditional small span metro stations.But the column itself takes up a lot of space,the existence of the column causes the waste of space and the congestion in the station,and the comfort and applicability are also greatly reduced.In order to solve the problems caused by the small span of the traditional subway station,how to effectively develop and use the large span subway station without column has attracted the attention of the peoleo of academic circle.At present,many successful cases of large-span and no column subway stations have been built abroad.At the same time,there have been many plans and practices for large-span metro stations in China.The largest span of metro stations in China is 15.8m.On the basis of the research and engineering practice on the long-span subway station,this paper will use the high-performance elastoplastic dynamic time-history analysis software to carry out static and dynamic time-history analysis on the prestressed large-span subway station structure.At the same time,this study will be further verified and compared with the data obtained from the structural model test of the prestressed large-span subway station in the laboratory of the Foundation Research Institute of China Academy of Building Research.The model test was divided into two groups:one and B.The similarity ratio of the two groups of model tests is 1:8.The top beam of model A is set up with vertical haunches,and the top beam of model B is elliptical.This article will do the following:1)On the basis of reading a large number of documents,the history and present situation of the large span subway station,the static analysis method of the subway structure,the seismic analysis method and the present situation of the use of the prestressed concrete in the largespan subway structure are reviewed.For the first time,the field model test results are combined with the static load and dynamic load numerical simulation results,for comparative analysis.2)The three-dimensional model of 1:1 large span subway station structure is established by using the finite element software PKPM-SAUSAGE,and the deformation and strength analysis and contrast of the subway station structure model A and model B are carried out under static load.It’s found that the performance of model Two is better than model One.3)Introduce the research status of prestressed and the special application method of ring prestress reinforcement.A comparative analysis is made between the model one and model B whether there is prestress or not.Based on the experimental data,the calculation results of PKPM-SAUSAGE are compared with the calculation results of ANSYS and the experimental results.The analysis shows that the settlement curves tend to be flat and the bearing capacity of the structures increase after the prestress is applied.The caculated results of flexure value of bottom beam are consistent with the results.4)Before the earthquake load is applied,the dynamic three axis test is completed first,to study the dynamic characteristics of the soil.The dynamic characteristics of the three axis test on the advance action of the model are studied,and the dynamic modulus and damping ratio of the model soil are measured,and the relationship between the dynamic stress and the dynamic strain is deepened.The results show that the damping ratio of the slity foundation is increasing under cyclic dynamic load.The dynamic elastic modulus tends to decrease.5)To study the seismic response and damage evolution process of prestressed large span subway stations through dynamic time-history analysis.It’s founded that the seismic performance of model Two is better than that of model One.The middle part of the bottom beam and the connecting part of the bottom beam to wall,and the connecting part of the middle plate to the wall is the weak part of the structure.