Research Into The Effection Of Adjacent Piles To Excavation

In recent years, with the rapid economic development, intensified urban modernization process, and massive consumption of urban construction land, the limited floor space of city can not meet the increasing need for life and work. Correspondingly, there emerge a lot of deep excavation projects, most of which are carried out close to the densely built areas, making it a must to consider the interaction between the excavation and the neighboring buildings when the foundation pits are designed and constructed.Additional deformation and moment of adjacent piles would be resulted from the soil movements caused by the excavation when the construction is near the piles.If the deformation is too serious, the pile foundation will be destroyed, and then the building on it will be damaged, too.However,the lateral soil pressure can be shared by the piles instead of excavation, so the deformation and moment of retaining wall can be decreased. Therefore,the study on the influence of adjacent piles on excavation has high research value and applicability.Based on the tremendous work done by researchers, home and abroad, this paper put an emphasis on the influence of existing adjacent piles on supporting structure of the earth pressure and the deformation in excavations.This paper mainly focuses on the following researches:1)An outline of the systems theory of excavation and the classic soil pressure theories, deduction of the improved soil pressure formula, according to the Prandtl Theory, by supposing that the soil sliding surface behind the retaining wall is a curve sliding surface——logarithmic spiral sliding surface;2)Elaboration on the finite element theories of geotechnical engineering and the selection of the appropriate soil constitutive model;3)A brief introduction to the procedure MIDAS/GTS,its application on the numerical analysis of the influence of adjacent piles on excavation, the result of which shows that the existence of adjacent piles has obvious and positive influence to excavation. 4)Rendering of exploratory opinions targeting two issues, with a project example, such as the soil pressure theories and a calculating method of lateral soil pressure when considering the influence of adjacent piles;5)Summery of the research work in this paper, and suggested research directions and ideas for further studies.