Ding-Jian Wang

Model tests are effective for studying the entire deformation and evolution process of reservoir landslides. The sensitivity of similar materials to seepage effects is crucial to the accuracy of landslide model testing. Based on a fuzzy evaluation of in situ sliding zone soil, this study compared three similar materials, using shear tests and microscopic SEM to assess the similarity. The optimal similar material (sliding zone soil: bentonite: standard sand = 50%: 20%: 30%) with a water content of 13.5% and a permeability coefficient of 3.8 × 10⁻⁶ cm/s was identified, simultaneously matching physical–mechanical properties and seepage effects. When the proportion of in situ sliding zone soil exceeds that of bentonite, the in situ sliding zone soil dominates the strength. Cohesion depends on interparticle cementation force and water film viscosity. Bentonite modifies these forces in stages, leading to a trend where cohesion (c′) first increases and then decreases with rising water content, while the internal friction angle (φ’) decreases continuously. Model test results indicate the failure mode of reservoir landslides is a three-stage traction-braking failure, evolving from initial shallow deformation to deep progressive failure and finally to overall large-scale instability. The proposed similar material exhibits reliable physical–mechanical and seepage similarity and can be directly applied in physical model tests of reservoir-induced landslides to reproduce the hydro-mechanical coupling behavior of sliding zones.

The long-term stability of anchored anti-dip slopes in hydropower and mining projects is threatened by corrosion-induced degradation of rock bolt systems. Existing deterministic models relying on global safety factors fail to capture localized failure mechanisms and inherent geotechnical uncertainties. This study aims to develop a probabilistic framework for assessing the spatiotemporal stability evolution of such slopes under progressive bolt corrosion. A novel Factor of Local Safety (FoLS) is introduced to quantify stability at individual rock column levels, enabling spatially explicit assessment. This metric is integrated with a time-variant mechanical model for bolt capacity loss and Monte Carlo simulation for uncertainty propagation. Applied to a representative slope, the framework reveals complex degradation patterns: failure initiates in the extremely active toppling zone, progresses to the moderately active zone, and ultimately extends to the passive and shear sliding zones. Sensitivity analyses highlight the critical influence of bolt inclination, yield strength, bolt-rock bond strength, and grout water-cement ratio. Comparative anchorage scenarios demonstrate the superior long-term effectiveness of lower-bench reinforcement. The study provides a novel, spatially differentiated approach for the design, maintenance, and risk management of anchored anti-dip slopes, emphasizing the necessity of dynamic stability monitoring over time.

Retaining structures in geological and geotechnical engineering are often embedded in unsaturated soil strata. Conventional methods for calculating earth pressure in unsaturated soils typically ignore the rotation of principal stresses in the backfill, a phenomenonknown as the soil arching effect. This study presents a novel analytical framework for determining the passive earth pressure in unsaturated soils that explicitly incorporates this arching effect. The proposed model accounts for both principal stress rotation and the hydro-mechanical coupling between matric suction and soil stress under groundwater influence. Based on the shear strength criterion for unsaturated soils, the model assumes a circular-arc trajectory for the rotating major principal stress, and hydrostatic seepage with matric suction distributed linearly with depth. Using a coordinate axis translation technique, quantitative relationships among lateral earth pressure, interlayer shear stress, and vertical stress are established. The force equilibrium equations for a horizontal differential soil element are then solved to derive closed-form expressions for the passive earth pressure distribution and resultant force. Validation against physical model tests and numerical simulations confirms the model’s accuracy and demonstrates its superiority over the extended Rankine theory, which systematically underestimates passive resistance. Parametric studies highlight the influences of groundwater depth, initial matric suction, and soil strength parameters. The proposed framework offers a more realistic and mechanically sound basis for the design of retaining structures in unsaturated soil environments.

It is of great significance to develop a failure criterion that can describe the orientation‐dependent behavior of transversely isotropic rocks. This paper presents a simplified parabolic model that is successful in predicting the strengths of rocks under different confining pressures and bedding angles. The model is a modified version of the normal parabolic criterion for intact rocks. The two orientation‐dependent parameters (σ_cβ and k_β) in the model show trigonometric relationships with the bedding angle, and they can be readily determined through uniaxial and triaxial compression tests. The shape of the failure envelope is determined by k_β, and σ_cβ only affects the level of rock strength. With application to 446 experimental data, the predicting results by the parabolic criterion are highly consistent with the experimental data, and the predictive capacity of the proposed criterion is better than those of the McLamore‐Gray and Tien‐Kuo criteria. Besides, the prediction errors for the high confining pressure condition and the bedding‐sliding failure mode are smaller than those for the low confining pressure and the non‐bedding‐sliding failure. Moreover, the prediction error almost remains steady with the decrease of data set, indicating that the proposed criterion is of high precision even if the experimental data are limited.