Fast Lagrangian Analysis of Continua in 3 Dimensions (FLAC3D) was employed to investigate the deformation characteristics of a staged excavated and supported foundation pit. Modified Cam-clay model was adopted to model the soil behavior and the interaction between soils and retaining structures was also taken into account in the numerical model. The deflection of retaining walls, the settlement of ground surface, the heave of excavation bottom, and the movement of the deep strata outside the excavation were analyzed. The ground surface settlement curves of the numerical model are basically consistent with the empirical ones from the existing literatures, so its feasibility is proved. The numerical results provide a useful reference for the design and construction of similar deep excavation projects.
