Abstract: The deformation of the retaining structure of the foundation pit of Qianhaiwan Station and that of the main structure of the existing Liyumen Metro Station are analyzed by means of FLAC3D finite element method, so as to minimize the interaction between the foundation pit construction and the existing Metro station. The study results show that the existing Liyumen station is favorable to the excavation of the new foundation pit because it can reduce the deformation of the piles on the same side by 24.7% and can reduce the axial force of the steel supports, which makes the excavation safer; on the other hand, the excavation of the new foundation pit will make the existing station rotate with a small value, which has little effect on the stability and safety of the existing station.

Key words: adjacent construction, FLAC3D, existing Metro station, foundation pit excavation, pile deformation, steel support