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The excavation of the foundation pit will have an impact on the adjacent buildings and the presence of the buildings will increase the risk of the construction of the pit. It is important to carry out studies on the interaction between the excavation and the adjacent buildings. Taking the Wenhua Road deep excavation project in Shenyang as the background, the influence of excavation on the displacement of the enclosure pile was analyzed through on-site monitoring data, and then a three-dimensional numerical model was established and compared with the on-site monitoring data to verify the accuracy of the model. Finally, the interaction behavior between the deep excavation and the building was analyzed under the parameters of the stiffness of the enclosure pile, the number of storeys of the building and the relative position of the deep excavation and the building. The results show that the use of retaining piles combined with anchor cable support will significantly reduce the deformation of retaining piles caused by excavation. The settlement and horizontal displacement of the building foundation caused by the excavation are within 5% with the increase in the stiffness of the bollard piles. The settlement and horizontal displacement of the building foundations increase by approximately 8% and 10% respectively for each additional 5 storeys of the building, and the horizontal displacement of the foundation piles near the building increases by approximately 5. 5% . At an angle of 30° or more between the building and the excavation, the deformation of the building foundation caused by the pit excavation was within 2 mm, and the horizontal displacement of the encasement piles was within 0. 8 mm. The results can be used as a reference for similar projects in the future. [ABSTRACT FROM AUTHOR]

Grouting is often used for active real-time control of deformation of adjacent important buildings and structures caused by excavation. However, when the distance between grouting and excavation is small, grouting may pose a threat to the excavation support system. At present, there is no effective way to solve that. Taking the excavation of a super deep subway station foundation pit was unalyzed adjacent to a hospital sensitive building in Tianjin as an example, the impact of the excavation of the foundation pit was analyzed and restores the building settlement by grouting in the soil layer between the super deep subway station and the hospital sensitive building. Because the vertical grouting has a great adverse effect on the excavation supporting structure, the inclined grouting is proposed in this paper to reduce the impact on the excavation. The results show that the adverse effect of inclined grouting on the adjacent station excavation is significantly reduced compared with vertical grouting, while the control of building settlement is still effective. When the angle of inclined grouting is too large to reduce the settlement of one side of the building adjacent to the grouting body, large upheavals will occur at other locations; Increasing the buried depth of the top of the grouting body can weaken the building uplift phenomenon and make the building settlement recover more evenly. [ABSTRACT FROM AUTHOR]