Study on the Influence of Construction Undercrossing Existing Station at Zero Distance in Confined Water

Abstract

Based on the Ciqu station project of Beijing Metro Line 17, this paper studies the influence of metro proximity construction in confined water stratum on the existing station, and puts forward relevant deformation control measures to solve the technical problem of new station zero distance under the complex geological conditions. Based on the systematic study of decompression and precipitation, embedment depth of ground wall and ground load of existing station, it is found that the deformation of existing station can be well controlled by taking precise precipitation, appropriately increasing embedment depth of ground wall and ground load of existing station at the same time, so as to achieve safe construction. Studies have shown that in the case of the existing station structure with deformation joints, the internal force of the structure is reduced by 58% compared with that of the station without deformation joints, The allowable deformation of existing station structure with reserved deformation joints is more than 3 times higher than that without reserved deformation joints, The existence of deformation joints improves the anti-damage ability of existing stations.