This study investigates slope stability under rainfall infiltration using numerical modeling in Plaxis 2D, comparing poorly graded sand (6.5% fines) and well-graded sand (11.9% fines) under high-intensity rainfall of 30 mm/h for durations of 8, 12, 18, and 24 h. The results indicate that, as rainfall duration increases, soil saturation rises, leading to reduced suction, lower shear strength, and decreased safety factors (S.F.s). Poorly graded sand shows minimal sensitivity to infiltration, with the S.F. dropping by only 4.3% after 24 h, maintaining values close to the initial 1.126. Conversely, well-graded sand demonstrates significant sensitivity, with its S.F. decreasing by 25.4% after 8 h and 73.7% after 24 h, due to higher water retention capacity and suction. This highlights the significant contrast in stability behavior between the two soil types. The findings emphasize the critical role of soil hydro-mechanical properties in assessing slope stability, especially in regions with intense rainfall. This study establishes a methodology for correlating safety factor variations with rainfall duration and soil type, offering valuable insights for modeling and mitigating landslide risks in rainy climates, considering the hydraulic and mechanical parameters of the soil.

In slope stability analysis, identifying the critical slip surface has always been a complex challenge. This study proposes a method to determine the critical slip surface of heterogeneous slopes while accounting for anisotropy. This method is grounded in a generalized soil anisotropic constitutive model and establishes a global equilibrium framework. It integrates global optimization techniques and employs the well-established Morgenstern-Price method to formulate the optimization objective function. The reliability, applicability, and stability of the method are demonstrated through comparative analysis with the results of two classical slope cases and the improved log-spiral limit equilibrium method. Additionally, the study investigates the impact of anisotropy-related parameters on the stability of heterogeneous slopes, providing new insights into how anisotropy influences slope stability and failure mechanisms.

The slope has an adverse effect on the ultimate bearing capacity of shallow foundations. Due to inherent variability in soil properties and geometric factors of slopes, designing a foundation on slopes is a perplexing and challenging task. The spatial variation in the soil's shear strength property is commonly ignored by the designers to avoid complexity in design. Shear strength property in real scenarios increases along the depth and simultaneously it poses spatial variability. This kind of randomness is modelled using a non-stationary random field. The proposed study aims to evaluate the probabilistic bearing capacity of strip footing on spatially varying slopes. The probabilistic bearing capacity factor is analyzed for different influential factors like geometry and footing placements, correlation distances and coefficient of variation of soil properties. Slopes exhibiting nonstationary characteristics contribute to remarkable differences in the bearing capacity of footing as compared to the stationary condition. The study highlights that the geometry factors, footing placements, soil spatial variability and most importantly the increasing trend of soil strength play a critical role in the bearing capacity and risk of failure of a footing. High variations in the failure probability can be observed even after considering safety factors.

In recent years, the increasing use of mulching in agricultural practices has been driven by its benefits in weed suppression, soil moisture retention, and improved soil structure. However, Korean farms typically perform mulching and soil covering separately, leading to excessive labor requirements. To address this issue, this study analyzes the safety of a newly developed mulching and soil covering machine. To evaluate its structural safety, strain gauges were attached to critical points of the machine, and strain data were collected under various Power Take-Off (PTO) and engine speed conditions. The measured strain was converted into von Mises stress and maximum shear stress, and the safety factor was calculated using the maximum shear stress theory and the strain energy theory. Additionally, fatigue life was predicted using the rainflow counting method, the Goodman equation, and Palmgren-Miner's rule. The results indicate that the safety factor ranged from 1.65 to 16.54 based on the maximum shear stress theory and 2.42 to 19.83 based on the strain energy theory, confirming that the machine can withstand operational loads without failure. Furthermore, fatigue life prediction revealed that the lowest estimated fatigue life is 14,575 h, equivalent to approximately 607 years of continuous use. These findings demonstrate that the developed machine possesses high safety, making it a viable solution for improving efficiency in mulching and soil covering operations.

Depth to bedrock (DTB) is a critical factor for rainfall-induced slope failures. However, the influence of uncertainties in these measurements, particularly at a small-scale, has not been fully understood. Numerical modeling was conducted to assess the impact of a variable bedrock topography on the stability of a real-world unsaturated slope. The simulations included a three-dimensional pore-water pressure estimation, derived from the numerical solution of the Richards equation, coupled with a slope stability assessment using numerical limit analysis. The study explored the potential of incorporating random fields (RFs) into an established DTB model to improve the understanding of rainfall-triggered landslides. The proposed methodology was applied to the analysis of a small watershed within the Papagaio River basin in Brazil, an area historically subjected to landslides triggered by rainfall events. Our main findings reveal that small variations in DTB can significantly impact the safety factor and probability of failure estimations. Furthermore, they influence the shape, location and failure volume associated to predicted landslides. The incorporation of RFs effectively addresses small- scale uncertainty in DTB, controls bedrock morphology, and enhances the assessment of probabilistic numerical modeling for landslide susceptibility. This study highlights the importance of accurate and comprehensive DTB characterization for assessing rainfall-induced landslides at local slope scale.

Slope stability analysis in 2D ranges from the classical and conventional limit equilibrium method to the robust and computationally demanding finite element (FE) analysis. Discontinuity layout optimisation (DLO) is an interesting intermediate method that applies an upper bound limit analysis with the assumption of rigid-perfectly plastic soil behaviour. Here, the whole soil mass is discretized using a set of potential slip-lines and optimisation is used to identify the critical mechanism that can be formed from a subset of these lines that dissipates the least energy. This method has only been used for isotropic soil models, except for rare studies that included an anisotropic model. This paper introduces the use of an anisotropic failure criterion in DLO, based on the total stress-based NGI-ADP model. The performance of DLO with this simplified NGI-ADP model is compared with respect to failure mechanism and safety factor determined by corresponding FE analysis. The results show good agreement between the two methods and highlight the use of DLO as a powerful method with straightforward input parameters and low computational time for slope stability assessment.

The stability of a slope located between the Belen and El Espejo sectors, Merida, Venezuela with high seismic hazard, due to the presence of the active Bocono Fault, which together with high rainfall and steep slopes, represent triggering factors where the slopes are prone to landslides. Through the Limit Equilibrium (LEM) and the Finite Element (FEM) Methods, we seek to identify the area's most prone to damage in the event of a landslide. The slope studied is located in an area unfavourable geomorphological zone, due to the erosive action of the Chama river that undermines it, generating gullies with detrital flows that affect its stability. The study of slope stability began with the compilation and review of bibliographic, the collection of soil samples for laboratory tests and the calculation of its properties and geomechanically parameters. The data obtained are used for the study of soil behavior and the calculation of the safety factor through of the Slide and Plaxis programs. It was determined that the slope is more unstable for the saturated pseudo-static condition in both programs. It is recommended to implement bioengineering as slope stabilization methods, in the upper zone of the slope, where there is damage to houses that are in danger, suggesting the biomantle, double torsion mesh and passive anchors, as a proposal of recommendation for the stabilization of the slope studied.

The rigid and fixed diaphragm wall (RFD) is a novel strut-free retaining wall system. This system needs a rigid connection between diaphragm panels. However, in Indonesia, constructing the rigid connection between diaphragm wall panels is scarce. The main objective of this study is to investigate the effectiveness of the RFD system on lateral wall deflection and excavation stability considering anisotropic factors due to joints in the diaphragm wall panels. First, the soil and structure parameters of the three-dimensional finite element model were validated through a well-documented braced excavation case history, which is located in Central Jakarta. Then, the RFD system was introduced to the 3D model. Some parametric studies were also conducted by varying several parameters to understand their influence on safety factors and wall deflections. The analysis results indicate that the implementation of the RFD system yields positive outcomes in controlling lateral deformations. The length of buttress walls and the use of cap slabs significantly affect excavation deformations and safety factors, while the depth of cross walls and buttress walls has a less significant impact. The presence of joints in the diaphragm wall panels causes the wall to be anisotropic, resulting in a reduction in wall stiffness. The reduction in wall stiffness leads to an increase in lateral wall deformations and a decrease in the excavation safety factor.

Earthquakes and groundwater are pivotal factors affecting slope stability. However, the majority of previous studies have focused on these factors individually, neglecting their combined effects. Hence, this paper aims to develop a framework using the kinematic approach of limit analysis to investigate the stability of slopes in partially saturated soils under the combined effects of seismic force and pore-water pressure. The pseudodynamic method (PDM) was employed to capture the temporal-spatial effect of horizontal and vertical seismic waves. Variations in suction and effective unit weight profiles with moisture content under steady-state unsaturated flow were considered. External rates arising from both static pore-water pressure and earthquake-induced excess pore-water pressure were incorporated into the energy-balance equation. With the aid of gravity increase method (GIM), an explicit expression of safety factor (FS) was derived and optimized using a genetic algorithm (GA). The validity of this approach was verified through a comparison with existing solutions. Parametric analyses were conducted to explore the influence of varying groundwater level, seismic coefficients, suction, threedimensional effects, excess pore water pressure, unsaturated flow types, and pseudo-dynamic parameters, on the FS and critical sliding surface of slopes in partially saturated slopes. This framework can provide a good reference for the safety design of reservoir slope under the combined effects of earthquakes and groundwater.

Slope failures are a significant natural geohazard in hilly and mountainous regions, often resulting in loss of life and infrastructure damage. The Muketuri-Alem Ketema road in Ethiopia is particularly vulnerable to landslides due to colluvial deposits on steep slopes from the higher northeastern plots to the lower Jemma River valley. This study investigates the characteristics of colluvial soil and evaluates the stability of slopes prone to landslides. It combines geophysical data, penetrometer tests, laboratory analyses, Google Earth images, and detailed field visits to assess the soil and bedrock composition and structure. Numerical methods, including limit equilibrium (Bishop, Janbu, Spencer, and Morgenstern-Price methods) and finite element methods, were used to analyze slope sections under various saturation conditions and simulate different rainfall patterns. The results indicate that the Bishop, Morgenstern-Price, and Spencer methods produce similar safety factors with minimal differences (<0.3%), while the Janbu method shows more significant variation (1.5%-5.6%). Safety factor differences for sections A-A and B-B range from 5.26% to 9.86% and 3.5%-4.7%, respectively. Simulations reveal that short-term saturation significantly reduces the stability of the upper slope layer by 20%-46.76%, and long-term saturation decreases the entire slope by 26.81%-46.76% compared to dry conditions due to increased pore water pressure and self-weight. Long-term saturation effects, combined with dynamic loads, can further reduce colluvial soil stability by over 50% compared to a dry static state. The finite element method predicts larger failure zones than limit equilibrium methods, emphasizing the need for accurate predictions to characterize slope behavior during failure and inform stabilization decisions. This study provides crucial data for maintaining and planning the Muketuri-Alem Ketema Road, highlighting slope performance over time and the effectiveness of stabilization techniques.