Double-layer structure model and FEM calculation of dewatering of deep foundation pits

In consideration of different characteristics of water flows in different hydrogeological stratums and the non-linear relationships between hydraulic conductivity coefficient, storativity, and physical-mechanical parameters of soil-layers during the dewatering-consolidation process, a double-layer structural numerical model and FEM are put forward to calculate the groundwater flow during the process of foundation pit dewatering. With the model, the groundwater table of each soil layer can also be obtained. As an example, the model is applied to calculation of the dewatering process for the south anchor foundation pit of the Runyang Yangtze River Highway Bridge. The results show that the double-layer structure model provides a new method for nonlinear coupling calculation of the dewatering of deep foundation pits and settlement, for prediction and control of soil deformation of foundation pits, and for engineering construction and design.