Finite Element Method Analysis of the Bottom Upheaval in the Excavations of Deep Foundation Pit

摘要

Based on seepage - consolidation coupling theory, the 3D models of the excavation and dewatering excavation of the deep foundation pit considering the engineering piles and without the piles were simulated by the FEM software ABQUS. By comparison of the calculation results of those four models, the law of the bottom upheaval during the dewatering excavation is summarized. And the influencing factors of the upheaval deformation were analyzed. The results show that the dewatering process has a compacted effect on the soil and the plastic upheaval appears during the excavation (the position of the largest upheaval move to the concrete diaphragm wall). So the dewatering is beneficial to the stability of the foundation pit. Except that, the engineering piles have an obvious role of controlling the bottom upheaval.