Based on Biot consolidation theory and Terzaghi effective stress principle

a coupling numerical simulation was done to analyze the seepage field characteristics of foundation pit during the dewatering by FEM. Taking the dewatering practice of Jiuhuashan Tunnel foundation pit engineering for example

the shape of phreatic surface

the distribution of seepage velocity and the settlement of ground are analyzed; and the influences of different distribution and depth of draining wells on the seepage field characteristics and ground settlement are compared. This research redounds to understanding mutual action mechanism between groundwater and soils. It provides credible directions to the draining well design for foundation pit engineering.