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Controlling the ground settlement and building deformation triggered by shield tunnelling, particularly within water-rich strata, poses a significant engineering challenge. This study conducts a finite element (FE) analysis focusing on the ground settlement and deformation of adjacent structures (with a minimum distance of 2.6 m to the tunnel) due to earth pressure balance (EPB) shield tunnelling. The analysis incorporates the influence of groundwater through a 3D fluid–solid coupling model. This study assesses the effects of tunnelling on the behaviour of nearby buildings and introduces two mitigation strategies: the vertical partition method and the portal partition method. Their effectiveness is compared and evaluated. Our findings reveal that the deformation curves of the stratum and the building are influenced by the accumulation and dissipation of pore pressure. The vertical partition method reduced surface settlement by approximately 70%, while the portal partition method further minimized building deformation but required careful application to avoid issues like uplift. Both methods effectively mitigate the impacts of tunnel construction, with the portal partition method offering superior performance in terms of material use and cost efficiency. This research provides a scientific foundation and technical guidance for similar engineering endeavours, which is vital for ensuring the safety of metro tunnel construction and the stability of adjacent buildings. [ABSTRACT FROM AUTHOR]

Shield tunnel structures are commonly found to be overdeformed in Eastern China soft ground due to adjacent engineering activities. Grouting treatment could serve as a viable solution to actively reduce the excessive diametrical expansion of tunnel linings. However, understanding the grouting-induced effects on adjacent tunnel structures remains preliminary due to the scarcity of well-documented case histories. In this study, a field experiment was conducted to explore a shield metro tunnel's real performance during grouting treatments. An extensive monitoring scheme was deployed while varied geometrical grouting arrangements were carried out. The tests provided a comprehensive database of the tunnel responses in multiple temporal resolution levels, both during the entire course of the grouting treatment and within single grouting operations. Investigations are carried out over the influencing factors of the grouting efficiency. The experimental observations suggest that grouting efficiency tends to evolve with time and can be affected by various geometrical grouting parameters. Observations are also presented and discussed in detail for the influence of grouting history on the convergence distribution and the tunnel's performance after the termination of all grouting operations. Time-variant behaviors of the tunnel are depicted in detail, such as the convergence recovery and rebound during the grouting process. Overall, this case study brings new insights into understanding the grouting-induced tunnel lining response. It can also serve as a benchmark for further theoretical and numerical studies. [ABSTRACT FROM AUTHOR]