Strength anisotropy and heterogeneous rotated anisotropy are prevalent phenomena in natural slopes. Previous studies have underscored their significance in slope stability analysis. However, in previous slope stability analyses, the effects of strength anisotropy and heterogeneous rotated anisotropy on slope stability were studied separately, without considering their coupled effect. This paper aims to propose a probabilistic analysis framework of slope stability considering the coupled effect of strength anisotropy and heterogeneous rotated anisotropy. Through an undrained clay slope case, the proposed probabilistic analysis framework is examined. The influence of strength anisotropy and heterogeneous rotated anisotropy on slope stability is investigated. The results show that the proposed probabilistic analysis framework of slope stability considering the coupled effect of strength anisotropy and heterogeneous rotated anisotropy is effective. Both strength anisotropy and heterogeneous rotated anisotropy have an important influence on slope stability. Furthermore, the statistics of safety factor including mean value, coefficient of variation, and reliability index, vary with the strength anisotropy coefficient, the heterogeneous anisotropy coefficient, and the rotational angle. The smaller the strength anisotropy coefficient, the larger the heterogeneous anisotropy coefficient, and the smaller the reliability index. The rotational angle of strata corresponding to the minimum and maximum values of the slope reliability index is sensitive to the strength anisotropy coefficient, but not to the heterogeneous anisotropy coefficient.

Watery strata and the influence of pore water pressure cannot be ignored when calculating the deformation of existing tunnels induced by the excavation of new undercrossing tunnels. Many parameters can affect the deformation of existing tunnels during the excavation of a new undercrossing tunnel. In this work, an optimized method was developed for calculating the settlement of an existing tunnel undercrossed by a newly excavated tunnel in water-rich strata. This method includes a deterministic calculation model and a probability analysis model. Based on the constitutive behavior of the soil and the poroelasticity theory, the excess pore water pressure at the axis of the existing tunnel was obtained and used in the deterministic calculation model, which computes the deformation of the existing tunnel. In addition, we established a probability model based on Kriging metamodeling, the Latin Hypercube sampling (LHS) and Monte Carlo sampling (MCS) methods, and conducted global sensitivity analysis (GSA) and failure probability analysis. The optimized parameters can be input into the deterministic model to make more accurate predictions. The optimized method was applied in and validated by a metro project in Beijing.