Study on seepage-stress coupling of deep foundation pit based on displacement back analysis

Abstract

Abstract: Based on the measured data during the excavation of a deep foundation pit in Shenzhen, the physical and mechanical parameters of soil are obtained by back analysis program. After obtaining the soil parameters in line with the actual conditions, the finite element software ABAQUS is used for numerical calculation to analyze the influence of layered excavation on the deformation of foundation pit under seepage conditions, mainly including the uplift of the soil at the bottom of the foundation pit, the deformation of the foundation pit after excavation, and the underground. The deformation of the diaphragm wall and the permeability coefficient of the strong permeability soil layer are changed to analyze the deformation of the foundation pit. The back analysis program and finite element software are used to simulate the construction process of the actual project, and the simulation results are compared with the actual monitoring results. The results show that the deformation of foundation pit calculated by the combination of back analysis program and finite element software is closer to the actual situation. The change of permeability coefficient of strong permeability soil layer has the greatest impact on the uplift of soil at the bottom of foundation pit.

Key words: back analysis, seepage, deep foundation pit, finite element, deformation

CLC Number:

TU473

TANG Xiao-lin, DONG Jian-hua, WU Xiao-lei, WANG Lu. Study on seepage-stress coupling of deep foundation pit based on displacement back analysis[J]. Journal of Lanzhou University of Technology, 2024, 50(5): 139-146.

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