| With the development of city, development and utilization of underground-space has been promoted and foundation has become the main subject in geotech-nical engineering. Often in densely populated urban excavation, foundation con-struction not only to ensure stability, but also to meet the deformation requirements to ensure that the excavation around the existing buildings,structures, underground pipelines and roads safe. The existing building piles in the vicinity of excavation foundation are typical of passive piles because its force deformation characteristics are different from the traditional active loaded piles due to displacement of soil.This paper combines with an instance of an underground channel excavation and applies three-dimensional finite difference method professional software to build the corresponding numerical analysis model on the basis of existing passive pile theories and methods.Numerical results basically agree with the measured data, which shows that numerical model can simulate efficiently the impact of excava-tion on deformation of the adjacent pile.On this basis, for a typical soft soil in Nanjing, the author analyzes the impact of excavation on the adjacent pile groups'settlement, lateral displacement, bending moment, axial force and compares it with pile with the position.Then,author uses the single factor analysis to further study of the mechanical properties of soil, retaining structure insertion ratio, retaining structural stiffness, bottom depth of passive piles, foundation and pile distance and other factors on the impact of changes of neighboring piles, and obtained some of meaningful conclusion of the deep foundation design and construction. Author puts forward relevant measures which decrease or eliminate the impact of excavation on the adjacent piles. |
