Numerical Analysis of the Stability of Excavation Support and its Impact on Factory Foundation

Abstract

This paper establishes a three-dimensional detailed numerical model of foundation pit excavation using the finite element simulation software Midas GTS NX to analyze the deformation characteristics of the excavation support structure, factory cap foundation, and pile foundations under three working conditions. The study shows that during the excavation process, due to lateral soil movement, the maximum horizontal displacement of the excavation support piles is concentrated in the middle and lower parts, while the vertical displacement is influenced by the reinforcing effect of the pile foundations. The support piles closer to the piles exhibit smaller vertical displacement, while those farther from the piles exhibit larger displacement. The horizontal and vertical displacements of the cap beams and steel pipe supports show relatively symmetric distribution. In the case of pile foundations and cap foundations, the impact of the excavation on horizontal and vertical displacements is small, with the largest displacement concentrated in the upper part of the pile foundations and the middle inner part of the cap foundations. In conclusion, the impact of foundation pit excavation is minimal on the displacement of pile foundations and cap foundations due to the shallow excavation depth and good overall stability of the excavation support structure. However, the numerical simulation only considers ideal conditions, and variations during construction are not fully reflected. Therefore, construction quality must be strictly controlled during the project, especially regarding the construction quality of cement-soil mixing piles, to ensure the smooth progress of the project.