This paper presents a method for analyzing slope stability in anisotropic and heterogeneous clay using a strength reduction finite element method (SRFEM) integrated with the level set method (LSM). Anisotropy refers to the inherent anisotropy in the clay's strength, while heterogeneity describes the spatial variability in strength parameters. The static LSM uses a zero level set function to model heterogeneous clay slopes. The method is validated through undrained slope stability analyses on different types of anisotropic clay and heterogeneous fields, showing its effectiveness in modeling anisotropic shear strength and capturing the characteristics of heterogeneous regions. The results indicate that the proposed method accurately predicts factors of safety and slip surfaces across various soil conditions, accounting for both anisotropic and heterogeneous characteristics.

The experimental studies were performed to examine the failure mechanism and the capacity of BFRP bolt-anchorage system under laboratory and field conditions in supporting clay slopes in Sichuan Basin, China. The results indicate that BFRP anchor bolts, designed based on the principle of equal strength replacement between bolt tensile strength and the bonding strength of the first interface, can meet the safety standards required for slope engineering. During the stable phase of the slope, the mechanical behavior and deformation characteristics of BFRP anchor bolts are comparable to those of steel anchor bolts, with the axial force of BFRP bolts being 1/3 to 1/4 lower than the designed value. When the slope enters the accelerated creep stage, the axial force of steel anchor bolts exceeds the designed value by 40 %, while the axial force of BFRP bolts remains at only 2/3 of that of steel bolts. The failure mechanisms of the BFRP bolt-anchorage system primarily involve shear failure at the bolt-mortar interface and pullout failure of the bolt body, which are attributed to the cumulative damage of the polymer material. Based on the experimental findings, it is recommended that the minimum tensile safety factor for BFRP bars used in temporary slope support should be set at 1.26. This study enhances the understanding of BFRP anchorage systems in clay soil environments and provides valuable insights for the design and construction of infrastructure projects in similar geological conditions.

A remote monitoring system based on the global navigation satellite system was established at the Limin Tunnel portal of a high-speed railway to investigate the damage evolution of silty clay slopes in cold regions. Displacement, temperature, and soil moisture data were collected from four locations susceptible to instability. A discrete element model of the slope was established based on the measured data. Moreover, a coupled expansion method incorporating water-ice particle phase transition was used to analyze the microscopic damage characteristics, including surface displacement, particle interactions, and internal crack development. The results show that displacement variation is most pronounced during rapid freezing and fluctuating thawing phases, with the slope's toe experiencing more significant displacement than its crest. During rapid freezing, soil particle contact failure occurs when the bond strength between clay particles is insufficient to counteract the frost heave pressure. The development of cracks in the silty clay is rapid, with shear cracks accounting for 90.43% of the total.

Piles are inevitably installed on sloping coastlines or inclined seabeds to support offshore wind turbines, offshore bridges, and other structures. The objective of this paper is to develop an analytical method for investigating the lateral response of short piles near clay slopes. The soil-pile interaction is modelled by a two-spring model which is used to describe the soil resistance around the pile and the horizontal shear force at the pile base. Considering the combined effect of slope angle and near-slope distance, the ultimate soil resistance along the pile is divided into three cases based on the nearby soil flow mechanism. The soil-pile-slope surface deformation mechanism is established according to the rotational deformation characteristics of short piles. In contrast to the modification of the initial stiffness, the p-y curve around the pile is constructed by considering the deformation mechanism. The accuracy of the analytical method is verified by comparing its results with two piles on level ground and five piles near slopes. Considering the soil-pile-slope deformation mechanism, the secant stiffness of the p-y curve is automatically adjusted and reduced without the need for additional numerical simulations or pile tests to determine the reduction factor of the initial stiffness.