Study On Construction Technology Of Open Cut Special-Shaped Subway Station Connecting With Existing Station

In recent years,with the continuous increase of urban population and buildings,urban land has become increasingly tight.Comfortable,convenient,and urban land-saving subway transportation has entered a stage of vigorous development.However,the existing subway stations and lines in the urban underground space are complicated,and the problem of connecting new subway stations to existing underground stations frequently occurs.For this reason,this paper takes the actual engineering as the background,and adopts the method of combining indoor scale model test and numerical simulation.An in-depth study is carried out on the permanent structure demolition of the new station construction and the structural connection of the two stations in the zero-distance side connection of the new special-shaped subway station to the existing station.The specific research contents and results are as follows:(1).Through the indoor scale model test,study the construction problem of zero-distance connection of new special-shaped stations to existing stations.The strain and stress change laws of the existing station structure and the new station structure after the construction of the special-shaped station are summarized.(2).Through the numerical simulation method,study the stress distribution law in the connection between the new special-shaped station and the existing station and compare it with the model test.Then,the main structure and soil displacement change laws of the two stations were studied,including: the influence range,the displacement value change range,the extreme value position,and the displacement change partition.Based on the simulation results,construction monitoring suggestions are given.(3)The dismantling sequence of the connecting parts of the two stations is studied by numerical simulation method.The law of stress,displacement and influence on the soil structure of the two stations under different demolition sequences is proved,and the demolition procedure with the least influence on the station structure and the surface soil is given.