Numerical Simulation Of Construction Settlement Of Metro Station Based On Seepage-Stress Coupling Analysis

The main construction of the main station of Line 2 of Jiefang Road Station of Changchun Municipality is taken as the engineering background.The influence of seepage stress coupling on the settlement of the main railway station is studied by means of theoretical analysis,numerical simulation and actual monitoring data.Firstly,the research significance of seepage-stress coupling in subway engineering construction is briefly introduced.Then,the mathematical model of seepage-stress coupling analysis is deduced and the solving conditions are determined according to the actual engineering problem.By artificially setting three different water level environments,the finite element software MIDAS/GTS was used to establish three corresponding numerical simulation models of seepage-stress coupling.The numerical analysis of the first water level seepage stress coupling model,the second water level seepage stress coupling model and the third water level seepage stress coupling model are carried out respectively.The settlement process and the settlement result of each stage under three water level conditions are obtained.The settlement of surface and the caverns under three water level conditions are selected and analyzed respectively.Determine the influence of seepage stress coupling on the settlement of the main railway station in three water level environments.And the settlement monitoring data and the numerical simulation settlement data are compared and analyzed to verify the accuracy and validity of the numerical simulation settlement calculation.Through the above research methods and research contents,the following conclusions are obtained:(1)Through numerical analysis and comparison with the monitoring data,it is determined that the numerical simulation results are consistent with the monitoring data.Therefore,the numerical analysis model and the calculation results are correct and reliable.(2)During the whole construction process,The final settlement of the surface above the central axis of the first water level is the largest,146.62 mm,and The settlement above the central axis at the second water level is 135.15 mm,and The surface settlement above the central axis at the third water level is the smallest,112.21 mm.The surface settlement of water level one are 8.49%and 30.67%higher than the water level two and the water level three.The surface settlement of the water level two is 20.44%higher than the water level three.(3)In the whole construction process of the main structure,the final settlement of the water level one is 75.48mm,and the settlement of the water level two lower,is 64.82mm.The final settlement of the water level three is 46.12mm.The settlement of the water level one is 16.45%and 63.66%higher than that of the water level two and the water level three respectively,while the water level two is more than 40.55%of the water level three.(4)Based on the comparative analysis,the seepage-stress coupling effect caused by groundwater seepage has a great influence on the settlement of the main project.The groundwater level during the construction of the subway station is controlled by precipitation,Making it stable in a lower position.The settlement of the surface and the settlement of the tunnel are greatly reduced.Effectively reducing the risk of the main structure of the construction process to ensure the smooth progress of the project.