Slope Stability Analysis Research Articles

Reservoir Slope Stability Analysis under Dynamic Fluctuating Water Level Using Improved Radial Movement Optimisation (IRMO) Algorithm

External water level fluctuation is the major trigger causing reservoir slope failure, and therefore it is of great significance for the safety assessment and corresponding safety management of reservoir slopes. In this work, the seepage effects stemming from fluctuating external water levels are given special analysis and then incorporated into the rigorous limit equilibrium method for assessing the stability of reservoir slope. An advanced metaheuristic intelligent algorithm, the improved radial movement optimisation (IRMO), is introduced to efficiently locate the critical failure surface and associated minimum factor of safety. Consequently, the effect of water level fluctuation directions, changing rates, and soil permeability coefficient on reservoir stability are investigated by the proposed method in three cases. It is found that the clay slope behaved more sensitively in stability fluctuation compared to the silty slope. With the dropping of external water, the higher dropping speed and lower soil permeability coefficient have worse impacts on the slope stability. The critical pool level during reservoir water dropping could be effectively obtained through the analysis. The results indicate that the IRMO-based method herein could effectively realise the stability analysis of the reservoir slope in a dynamic fluctuating reservoir water level, which could provide applicable technology for following preventions.

Slope Stability Analysis Using the Rock Structure Rating (RSR) Method And Atterberg Limit at Riau - West Sumatra Cross road Km 165 Harau Subdistrict, Lima puluh Kota Regency, West Sumatra Province

Slope Stability Analysis Using the Rock Structure Rating (RSR) Method And Atterberg Limit at Riau - West Sumatra Cross road Km 165 Harau Subdistrict, Lima puluh Kota Regency, West Sumatra Province

Determination of Critical Slip Surface in Loose Rock Slope Stability Analysis

Determination of Critical Slip Surface in Loose Rock Slope Stability Analysis

A comparative study of slope stability analysis via Geo5 using IoT framework

In mountainous regions, landslides pose significant and frequent threats, causing extensive damage due to their destructive nature and frequency, therefore determining their likely occurrence sites and environmental factors is essential for hazard assessment. The infinite slope approach characterizes slope stability using a factor of safety (FOS) to assess the likelihood of slope failure and is frequently used to estimate the occurrence of shallow landslides on soil and regolith-covered slopes. Various methods have been used to evaluate and spread uncertainty across such models. Slope failure is a significant geological occurrence brought on by topography and weather, which result in a variety of ground movements. Engineers must plan and implement measures to mitigate hazards, safeguarding both lives and property from potential risks and dangers by using an adequate stabilizing solution. Technology and software advancements have made it simpler than ever to handle challenging issues that used to require a lot of time in every profession. Over the past decade, software utilization in civil engineering has surged. GEO 5 is a versatile program gaining prominence, aiding in the resolution of diverse geotechnical challenges. Through the installation of IoT cameras in various sand and clay areas along the bank of the Mahandi River in Odisha, we have gathered the data necessary to develop the region in this case. a select selection of which we have chosen for our research. In this study, slope stability-related modules have been carefully examined and used for the analysis of slope stability. Using the GEO5 program, the geometry of the issues was established, and the study took into account several stability optimization techniques. Additionally, the cost factor of various reinforcing techniques was calculated and contrasted.

Non-parametric fragility curves for probabilistic risk assessment of rainfall-triggered landslides

Fragility analysis of slopes under rainfall condition express the conditional probabilities of exceeding prescribed slope limit states under a range of rainfall intensities, which is the basic and pivotal procedure in rainfall-triggered landslide risk assessment. Classical fragility analysis methods of slopes always develop fragility curves with the assumption of lognormal distribution. The validation of assuming the shape of fragility curves as lognormal distribution remains a open question in practice. In addition, the existing fragility analysis of slopes under rainfall condition have not dealt with the effect of spatially-variable geo-material parameters. In the present study, a novel fragility analysis methodology is proposed for the construction of non-parametric fragility curves of slopes under rainfall condition, in which the spatially-variable soil properties are taken into account. The non-parametric fragility curves are developed by the calculated slope failure probabilities under various rainfall intensities on the basis of probability density evolution theory, without restricting fragility functions to some assumed distribution models. With the proposed method and a set of probabilistic slope rainfall seepage and stability analyses, non-parametric fragility curves, fragility surface using two rainfall intensity measures and time-dependent fragility curves of a slope subjected to various rainfall scenarios are obtained for rainfall-triggered landslides risk assessment.

Cut Slope Stability Analysis on Terrain with Slope at Besishahar, Lamjung

Building construction on sloped terrain presents a myriad of challenges that necessitate specialized engineering solutions and careful planning. Though the cut slopes are prone to failure, the increase in urbanization makes construction in such landscape inevitable. The complex topography of this region poses significant scientific and technological challenges, demanding innovative solutions for slope stability analysis and effective mitigation measures. This study incorporates geotechnical and geological study of the Manab Sewa Ashram Site in Besishahar, the cut slope failure analysis using Limit Equilibrium Method and Kinematic failure analysis and suggesting mitigating measure. Three different profiles with critical slopes were selected to represent the overall area for Slope Stability modeling and Kinematic Failure Analysis. The calculation of Factor of Safety for slope stability was done using Slide v.6.020 software under Rocscience package. Since non-engineered cutting of slopes is predominantly existing in the context of Nepal, slope management contributes by majorly focusing on the safety of the structure on or around the slopes.

Mechanics of Rainfall-Induced Landslides after a Prolonged Dry Period Based on Laboratory Tests and Numerical Models Incorporating Soil-Water Characteristic Curves

In India, particularly within its Northeastern territories, landslides triggered by rainfall following dry periods are a major concern, consistently causing extensive damage to both life and infrastructure. This study focuses on mitigating their impact through preemptive measures, with an emphasis on analyzing slope stability to determine critical intervention points. The investigation includes experimental tests on soil samples to assess key parameters, such as soil matric suction and unconfined compressive strength, alongside an analysis of slope failures during the 2017 monsoon in Mizoram’s Lunglei district. Employing Soil-Water Characteristic Curves (SWCC) derived from ASTM D5298-10 standards and a microwave drying technique for preparing soil samples, the research evaluates the condition of the slopes before and after monsoonal rains. This study utilizes a blend of numerical modeling and empirical laboratory investigations to explore the factors contributing to slope instability. The findings underscore the necessity of advanced landslide warning systems, suggesting that a deeper understanding of rainfall-induced slope failures could significantly enhance disaster preparedness and reduce potential damages.

3D large deformation modeling of the 2020 Gjerdrum quick clay landslide

A quick clay slide in Gjerdrum, Norway, occurred at 4 a.m. on 30th December 2020, killing ten people and destroying houses, roads, and other infrastructures. Approximately 1.35 million cubic meters of clay were released, a large volume liquefied, and debris was transported almost two kilometers downstream. An investigation following the slide determined that the slide was initialized in a 30-meter-high slope after 2-to-2,5-meter vertical erosion in a small creek running along the toe of the slope. After the initiation, the slide developed retrogressively in the order of 500 meters backward and sideways over a period of about 2 minutes. A conventional geotechnical slope stability analysis explains the initial slide. However, more advanced numerical tools are needed to simulate the retrogressive mechanism and the debris flow. The aim of the paper is to demonstrate a 3D Material Point Method model to capture some of the mechanisms involved from initiation until the debris comes to rest and how this method can be used to reproduce and study the processes involved in large deformation landslides.

Combined Effect of the Microstructure and Mechanical Behavior of Lateritic Soils in the Instability of a Road Cut Slope in Rwanda

A very common hazard in Rwanda is represented by the instability of steep road cut slopes in lateritic soil. In its natural state, this material appears as a fine-grained weak and altered rock, generally in unsaturated conditions. Steep cut slopes made by this material could remain stable for a long time unless weathering weakens its mechanical behavior and heavy rainfall provokes a rapid landslide. This paper presents the results of an experimental investigation on the microstructural, petrophysical, and geotechnical properties of lateritic soil from a road cut slope located in Kabaya (Ngororero District—Rwanda), which was recently subjected to a landslide. The mechanical properties of the material are strictly related to the geological origin and history of the deposits, their formation environment, and weathering processes. These characteristics were revealed by peculiar microstructural features (micro-texture, porosity, and degree of alteration of original mineral paragenesis). The experimental investigations included identification and classification tests, direct shear tests on saturated samples, and swelling tests. This multidisciplinary approach provided insights into the relationship between geotechnical properties and the microstructural, petrophysical, and chemical characteristics of the altered rocks. This study showed how different levels of chemical alteration operated by weathering processes, in conjunction with brittle deformation related to the tectonic history, formed in the same site two shallow rock layers with similar macro-scale features and mechanical behaviors but markedly different microstructural and chemical properties. The innovative aspect of this research suggests an integrated multidisciplinary approach to considering microstructural aspects in addition to mechanical behavior in the slope stability analyses in lateritic soil. In particular, this study demonstrates the importance of such an approach since the failure mechanism is better explained if it is based on microstructural observations instead of considering the soil shear strength parameters only. This research helped to explain the formation of the landslide failure mechanism in a specific road cut slope, which could be assumed as representative of many other similar slopes subjected to landslides in Rwanda.

Stability analysis of ultra-high and steep reinforced soil fills slopes based on strength reduction

The research focuses on solving the important problem of slope stability in the field of civil engineering. The study adopted an advanced strength double reduction coefficient method for slope stability analysis, which considers the different influence weights of cohesion and internal friction angle, and reduces them with different reduction coefficients to describe the stability of the slope. The simulation experiment results indicate that the attenuation degree of cohesion and internal friction angle affects slope stability. When the reduction coefficient of cohesion increases to 1.737 and the reduction coefficient of internal friction angle increases to 1.201, the slope is prone to instability and failure, and the safety factor of the calculated result is 1.493. Moreover, when the anti-slip pile is set in the middle of the slope (1/2), and the slope is in a critical state, the bending moment and shear force suffered by the anti-slip pile are both maximum, so the reinforcement effect is also the best.

Numerical simulation analysis of slope stability from rainwater utilizing the Civil3D+Flac3D coupling

Building Information Modeling (BIM) technology serves as an effective means for engineering modeling and information integration, surpassing traditional two-dimensional approaches with its superior spatial analysis capabilities. While BIM has gained widespread applications in slope engineering, a gap persists in the integration between protective design and simulation analysis in terms of slope stability. This study employs literature review, theoretical analysis, software development, and numerical simulation methods to explore the application of BIM models in slope stability analysis. Through the integrated application of BIM model construction, mesh subdivision, and stability analysis, we address the deficiency in three-dimensional slope stability inherent in BIM by coupling Civil3D’s secondary development with Flac3D, a numerical simulation software. This approach not only addresses the shortcomings of numerical analysis software in constructing complex geological models but also employs a collaborative multi-software approach for comparison to validate its suitability in slope engineering. The results demonstrate that models built using BIM software are more comprehensive and possess high precision in numerical simulation, thus exhibiting significant practical value in real-world engineering applications.

The Investigation of Stability on Slopes Utilizing Reinforcement Gabion Walls and Concrete Piles for Mitigating Landslide Disasters

Introduction Landslides frequently occur along roads crossing mountainous terrain during the rainy season, posing a significant risk of severe disruption to land transportation routes. Efficient and accurate resolutions are essential in managing landslides to facilitate immediate transportation recovery, such as gabion walls and pile installation. Aim This article aimed to evaluate the effect of installing gabions and piles for safety measures on the stability of slope landslides. The analysis of slope stability was performed utilizing the Plaxis 2D software. For reinforced slopes, the Safety Factor (SF) value utilized as a benchmark for evaluating slope stability was SF ≥ 1.5. Methods An assessment of the stability of the slope was conducted under three conditions: its original state, after reinforcement with gabions, and after the integration of gabions with mini piles. The dimensions of the gabion setting, as determined by the L-W-H notation (length-width- height), were 2 m x 1m x 0.5 m and 1 m x 2 m x 0.5 m. The pile was designed to be 2.5 m long at the gabion's end. The analysis was conducted at 45°, 60°, 70°, and 90° slopes. Results Based on the results of slope stability calculations, an SF = 1.11 was determined under no reinforcement conditions. By applying reinforced gabion walls measuring 2 m in width combined with mini piles at a 45° slope, the best SF was achieved, which was 2.58. Conclusion Given the comparable topographical circumstances, it is expected that the outcomes of this analysis on slope stability will be applicable in mitigating the occurrence of landslides.

Study of slope stability analysis method based on equivalent Mohr‐Coulomb strength parameters of three‐dimensional stress state

AbstractMost rock slope stability analysis methods are based on the Hoke–Brown criterion under a two‐dimensional state of stress, which somewhat ignores the effect of intermediate principal stress. In this paper, by introducing the improved three‐dimensional H‐B criterion into the Meridian plane, the tangent line of a point on the H‐B strength envelope is regarded as its instantaneous equivalent M‐C parameter. Based on this, a formula for solving the equivalent M‐C strength parameters under a three‐dimensional stress state is established to describe the shear strength parameters of rock mass, considering different stress states. Taking three kinds of rocks as examples, the influence of the intermediate principal stress on their strength parameters is analyzed. On this basis, the realization scheme of the nonlinear strength reduction method is established, the stability of the slope is studied, and an example verifies the feasibility of this method. This method fully considers the nonlinear characteristics of rock slope strength parameters under a three‐dimensional stress state and provides a solid basis for slope stability analysis.

Recent advances in stability analysis and design of 3D slopes

Slope failures in nature and engineering are typically three-dimensional (3D). The rotational failure mechanism derived from the variational limit equilibrium (LE) method shows superior performance in the stability analysis of the 3D slope. In contrast to the traditional LE methods, it avoids arbitrary kinematical and statical assumptions. Stability charts obtained by the variational LE method are used to derive explicit expression equations of the safety factor, also known as the stability equations, for both 3D reinforced and unreinforced slopes. These equations are highly accurate and can provide a convenient means to assess slope stability in practical engineering. An example of a convex reinforced slope with a turning arc is illustrated in this study to investigate the effect of the 3D effects on the required reinforcement length for design. The results indicate that the 2D method underestimates the required reinforcement length when dealing with a 3D reinforced slope problem. Furthermore, a forensic analysis of the Yeager Airport reinforced slope is conducted within the framework of the variational LE method. The required strength for stability is found to be significantly less than the allowable strength of reinforcements without considering the decrease in soil shear strength. However, the required strength greatly exceeds the allowable strength when the decrease in soil shear strength is considered. The results verify that the decrease in shear strength of the weak layer is responsible for the collapse.

Slope Stability Analysis of Vetiver Grass Stabilized Soil Using Genetic Programming and Multivariate Adaptive Regression Splines

Slope Stability Analysis of Vetiver Grass Stabilized Soil Using Genetic Programming and Multivariate Adaptive Regression Splines

Stability Analysis of Open-Pit Bench Slope under Repeated Heavy Vehicle Loading Based on Stress-Corrosion Model

In the present study, we address an important and increasingly relevant topic in mining safety and efficiency, namely the stability of open-pit bench slopes subjected to daily heavy truck cyclic loading. Specifically, we focus on the stability of Zhahanur open-pit slope (Inner Mongolia region, China) and investigate the potential role of daily heavy truck cyclic loading in bench slope instability. To this end, we incorporate a stress corrosion model into the particle flow code to develop a time-dependent deformation model of the rock. With the established model, we quantitatively analyse the effect of heavy truck cyclic loading on the bench slope stability. Our results support the hypothesis that daily heavy truck loading can cause gradual downward deformation of a rock mass, leading to slope instability. To validate our numerical modelling results, we compare and analyse them with in situ monitoring data. Our study demonstrates the significant impact of daily heavy vehicles on bench slope stability in open-pit mines and provides a practical tool for assessing the long-term stability of open-pit bench slopes and optimising mining operations.

Back analysis of the shear strength parameters of 3D landslides with Bayesian approach and reliability theory

To establish an accurate model for determining the shear strength parameters of sliding surfaces while considering the variability and uncertainty of geotechnical parameters, a reliability back analysis method for parameters based on Bayesian theory and a three-dimensional slope stability analysis method are proposed in this paper. First, the prior information of shear strength parameters is updated according to the field test information based on Bayesian theory. Then, combined with the reliability theory, the influences of different two-dimensional and three-dimensional sliding surface shapes on the parameters back analysis are studied. The results show that the uncertainty of parameters decreases with the increase in the amount of test data after introducing the test data to update the mastered parameter information based on Bayesian theory, and it is of great significance to consider the shape and three-dimensional effect of the sliding surface accurately to improve the accuracy of parameter determination and slope stability analysis.

The three-dimensional stability analysis of piled slopes in unsaturated and inhomogeneous soils with nonlinear failure criterion

Under the nonlinear Mohr-Coulomb (MC) failure criterion, based on the upper-bound limit analysis theorem, the three-dimensional(3D) stability of piled unsaturated inhomogeneous slopes is analyzed. By incorporating the nonlinear strength parameters c t and φ t, the energy balance equation is established, and the explicit expression of slope safety factor (F S) is derived by the gravity increase method (GIM). In addition, a genetic algorithm (GA) is used to calculate the minimum F S. The results obtained were compared with those of existing literature to verify the effectiveness of the method used in this paper. The influence of nonlinear parameters on slope stability was studied through parameter analysis. The results show that the nonlinear parameters of soil have a significant influence on the stability of piled slopes. The F S increases with the increase of nonlinear coefficient and uniaxial tensile strength and decreases with the increase of initial cohesion of soil. In addition, the critical slip surface of the slope becomes shallower with the weakening of soil nonlinearity. Furthermore, ignoring the suction effect will overestimate the slope stability, and the slope stability intensified with decreased soil inhomogeneity.

Enhanced Rock Slope Stability Analysis: Integrating the Partial Factor Method into the Limit Equilibrium Method

Rock slope stability is crucial for sustainable design. Especially concerning natural or artificial rock-cut slopes. The stability of these slopes depends largely on features of rock mass, particularly discontinuities. Failure modes are determined by these features and are evaluated using kinematics analysis with stereographic projections. Various methods exist for analyzing rock slopes, including the limit equilibrium method (LEM), which assesses stability based on a factor of safety (FS). Conversely, the partial factor method (PFM), predominantly used in Europe, offers a more reliable and probabilistic approach, incorporating uncertainty factors. Although Eurocode, which employs the PFM, is widely utilized, it faces disputes and undergoes updates based on ISRM recommendations. The partial factor method is considered more conservative than the limit equilibrium method due to its comprehensive probabilistic approach. The choice between methods depends on project requirements, data availability, and expertise. This study compares the limit equilibrium and partial factor methods for rock slope analysis, concluding that the partial factor method is more conservative and sustainable for long-term stability assessment. Whereas, the traditional method is often used for short-term assessments.

A vector sum analysis method for stability evolution of expansive soil slope considering shear zone damage softening

Slope stability analysis is a classical mechanical problem in geotechnical engineering and engineering geology. It is of great significance to study the stability evolution of expansive soil slopes for engineering construction in expansive soil areas. Most of the existing studies evaluate the slope stability by analyzing the limit equilibrium state of the slope, and the analysis method for the stability evolution considering the damage softening of the shear zone is lacking. In this study, the large deformation shear mechanical behavior of expansive soil was investigated by ring shear test. The damage softening characteristic of expansive soil in the shear zone was analyzed, and a shear damage model reflecting the damage softening behavior of expansive soil was derived based on the damage theory. Finally, by skillfully combining the vector sum method and the shear damage model, an analysis method for the stability evolution of the expansive soil slope considering the shear zone damage softening was proposed. The results show that the shear zone subjected to large displacement shear deformation exhibits an obvious damage softening phenomenon. The damage variable equation based on the logistic function can be well used to describe the shear damage characteristics of expansive soil, and the proposed shear damage model is in good agreement with the ring shear test results. The vector sum method considering the damage softening behavior of the shear zone can be well applied to analyze the stability evolution characteristics of the expansive soil slope. The stability factor of the expansive soil slope decreases with the increase of shear displacement, showing an obvious progressive failure behavior.