The coupled FEM analysis of deforming slope of Zhaiba,the Three Gorges

The deforming slope in Minde primary school, Zhaiba, Yunyang county,the Three Gorges, is consisted of cliff debris, colluvial and diluvial deposits. There is an isolated aquifer, which is consisted of block and rubble stones under the center of the land site, and the underground water level is just below the ground surface. Uneven deformation had been induced by groundwater discharge via some concentrative piping channels due to road excavation in 1998-2000 construction periods. A coupling finite element method (FEM) of saturatedunsaturated soil seepage and deformation calculation has been presented to model the deformation and the ground failure. It has shown that a large range of both descending of pore water pressures and uneven deformation were in fact caused by groundwater discharge. The excavation unloading may only cause deformation of soils near the excavation face.