One major concern for excavation projects is the ground displacement generated around the excavated zone. In this paper, a 2-dimensional model analysis was made on non-linear ground behavior around excavation due to unsteady seepage of groundwater, taking into account the saturated-unsaturated theory by using Toyo-ura sand. The finite-element method and finite-different method were employed to study the space problem and time dimension, respectively. The numerical simulation code implemented by FORTRAN was applied to predict the flow-velocity distribution and the results of ground displacement. To validate the programming, a simple model was tested for comparison with tri-axial test data. The samples were made of Toyo-ura sand with a relative density of 90%. The programming also calculated flow-velocity distribution and ground displacement results of dewatering in excavation work over time. Results showed that the effect of horizontal displacement caused by seepage flow plays a very important role in the displacement field. This numerical simulation method provides a more reasonable computing scheme compared to traditional methods. All have theoretical meaning and applicable value, and also present useful references for the excavation stability and disaster prediction.
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