Difficulties related to seepage are frequently encountered in tunnel design and construction, especially in deep-buried tunnels. Nowadays, analytical solutions of steady seepage fields for deep-buried tunnel usually assume that the surrounding rock mass is homogeneous. In this study, analytical solutions of a steady seepage field for a deep-buried tunnel with grouting ring considering anisotropic flow are proposed. The proposed analytical solutions are verified by numerical simulations and parameter analysis are carried out. Results show that the seepage field of surrounding rocks around the deep buried circular tunnel is no longer uniformly distributed and presents elliptical distribution. The change of permeability coefficient of the lining structure has a great influence on the hydraulic head when the difference between permeability coefficient of lining structure and surrounding rock is not very large. The results show that the size of the grouting ring has more significant influence on the grouting effect.

Because of difficulty in mathematic solution, analysis of surrounding rock stress of shallow buried tunnel considering seepage force has always been a difficult problem. Seepage body force is introduced into governing equations and boundary conditions of an elastic plane. Then traditional complex variable method is expanded for the analysis of plane strain problems in relation to an elastic plane considering seepage effect. Subsequently, explicit analytical solutions of seepage field and stress field of a shallow underwater tunnel excavated in an elastic rock mass with uniform distribution of pressure and total water head on tunnel boundary as well as stress free on ground surface are derived. The analytical solutions are validated by numerical simulations and can be used to analyse stress variations of surrounding rock mass under seepage effect. Based on an example, influence of buried depth and water head difference between ground surface and tunnel boundary on the circumferential effective stress around the tunnel are discussed. It is found that directions of major and minor principal stress will exchange with each other with increase of total water head difference between ground surface and tunnel boundary, and stress distribution around tunnel tend to be uniform with increase of buried depth.

Displacement control is critical to the design of retaining walls, especially in urban areas, to avoid any potential damage to adjacent structures during excavations. In this study, model tests are first conducted to investigate the stress and deformation mechanisms of an embedded cantilevered retaining (ECR) wall during excavations. The development of the wall top displacement and the active and passive earth pressures acting on the ECR walls during excavations are studied. Upon the experimental observations, a displacement-dependent earth pressure coefficient is proposed to derive an analytical solution to predict both the active and passive earth pressure acting on the ECR wall (pile), where the displacement value and displacement mode of the ECR wall (pile) are taken into account. Comparisons between the model predictions and test results are carried out. A good agreement is observed, which shows the validity of the proposed solution. Based on the proposed solution, a displacement-controlled method for the design of ECR walls (piles) that takes into account the location of the rotation point is proposed. Parametric studies are conducted to demonstrate the impact of deformation control and excavation depth on the design parameters of ECR walls (piles).