Slope Stability

This paper presents the framework for the interim design guideline for the use of expanded polystyrene (EPS) block geofoam for slope stabilization and repair, based on the findings of the NCHRP Project 24-11(02) Phase I study. The overall objective of this research is to develop a design guideline as well as an appropriate material and construction standard for the use of EPS block geofoam for the function of lightweight fill in slope stability applications. The recommended design methodology included in the framework is based on an assessment of the existing technology and literature. The Phase II work will refine the interim design guideline framework and address some uncertainties in the current state of the practice of analyzing various failure mechanisms included in the design procedure. The completed research will consist of the following five primary research products: (a) a summary of the relevant engineering properties, (b) a comprehensive design guideline, (c) a material a...

ABSTRACT Slope stability analysis of soil with a weak layer sandwiched between two strong layers is considered as a complex geotechnical problem. In this problem, the objective function is non-convex and discontinuous with the presence of multiple strong local minima. Classical optimization techniques fail to converge to a valid solution unless a proper initial trial is adopted. Even though many new optimization algorithms have emerged, they have not been applied to geotechnical problems yet. In the present study, some recent swarm intelligence algorithms are adopted for some complicated example of slope stability problems and benchmarked with the traditional particle swarm optimization algorithm. From the results, it seems the levy flight krill herd algorithm is the most efficient method over proposed algorithms for this kind of problem. Copyright © 2014 John Wiley & Sons, Ltd.

Landslides at continental margins are natural hazards for submarine installations and coastal regions. The occurrence of gas hydrates at continental margins is thought to be one major cause for these slides. It is assumed that the decomposition of gas hydrates increases the water content of the host sediment and thus lowers the strength of the soil. In order to predict

The selection of separation process of organic compounds is a critical issue in the chemical industry. Different conventional methods, such as coagulation, precipitation, ion exchange, electrodialysis, adsorption, ultrafiltration and liquid-liquid extraction have been used for the separation processes since last so many years, but supported liquid membrane (SLM)-based separation processes have been predicted as a promising option. Ionic liquids (ILs) are considered a new miraculous chemical due their unique properties and large variety of applications in all areas of the chemical sciences. The use of ionic liquids as a liquid membrane phase results in the stabilization of the SLMs due to their negligible vapor pressure, possibility of minimizing their solubility in the surrounding phases and greater capillary force associated with their high viscosity, which can reduce the displacement of liquids from micron pores under pressure. This review article summarizes the role of ionic liquids in supported liquid membrane technology for extraction processes, stability of the membranes and show promise in the liquid/liquid extraction of organics from water, gases, amino acids, toxic metal ions from their aqueous solution and separating isomeric organic compounds. © 2011 Elsevier B.V.

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Catastrophic flank collapses have occurred at many stratovolcanoes worldwide. We present a three-dimensional (3-D) slope stability analysis for assessing and quantifying both the locations of minimum edifice stability and the expected volumes of potential failure. Our approach can search the materials underlying a topographic surface, represented as a digital elevation model (DEM), and determine the relative stability of all parts of the edifice. Our 3-D extension of Bishop's [1955] simplified limit-equilibrium analysis incorporates spherical failure surfaces, variable material properties, pore fluid pressures, and earthquake shaking. Although a variety of processes can trigger collapse, we focus here on gravitationally induced instability. Even homogeneous rock properties strongly influence the depth and volume of the least stable potential failure. For large failures in complex topography, patterns of potential instability do not mimic local ground surface slope alone. The May 18, 1980, catastrophic failure of the north flank of Mount St. Helens provides the best documented case history to test our method. Using the undeformed edifice topography of Mount St. Helens in an analysis of dry, static slope stability with homogeneous materials, as might be conducted in a precollapse hazard analysis, our method identified the northwest flank as the least stable region, although the north flank stability was within 5% of the minimum. Using estimates of the conditions that existed 2 days prior to collapse, including deformed topography with a north flank bulge and combined pore pressure and earthquake shaking effects, we obtained good estimates of the actual failure location and volume. Our method can provide estimates of initial failure volume and location to aid in assessing downslope or downstream hazards.

Some instability problems of cutting slopes were found along the main road alignment between Bandung and Majalengka, which is mostly lying on high slaking claystones. The main objective of this paper is to establish the findings of the study devoted to some slope instability problems in the claystones due to their propensity to slaking at selected locations of these cutting slopes. The slope performance analysis made during a field survey has obtained a plot of slope angles versus slope heights for the average stable conditions of the existing road slopes, which were then combined with the laboratory experiments of slaking tests, resulting in a standard chart to be suggested as a physical-based model for the cutting slope design. Based on this chart, the optimum slope design can be estimated directly from the input of lithological characteristics determined by simple and inexpensive field and laboratory tests.

The current study is aimed at putting the light on the role of emotional intelligence and emotional stability on
confronting crises in general and the existing crisis of COVID-19 which has global impact till the present moment.
Data were collected from different sources particularly the recent international scientific issues and publications as
Centers of Disease Control and Prevention (CDC) [1] as well as the current national issues. Data revealed that there
is lack of awareness regarding the existing pandemic of corona virus (COVID-19) which requires clearance of the
correlation between the physical and psychological impact on the human being all over the world. Also to clarify the
importance of the emotional intelligence and emotional stability in confronting the existing fear and anxiety caused
by corona virus. Finally there are certain recommendations could be taken in consideration to relieve panic and
anxiety among the people facing the stress of mixed symptoms and signs of corona virus and how to deal with this
crisis.

The objective of our work is the study of the influence of the dynamic load due to the use of the explosive in the stability of the slope of an open pit mine, for this purpose we used the method of limit equilibrium to calculate the value of the safety factor through the geotechnical software SLIDE. On the one hand the calculation was carried out under static loading and on the other hand the dynamic loading is taken into account, which allowed us to conclude that the dynamic load influences the safety coefficient. Finally, a proposal to stabilize the slope at through a reprofiling of the bench is presented.

Slope stability at open pit mining system for safety and economics element is critical issue with employees and equipment damage due to danger of slope failure at the mining environment. Commonly uncertainty on slope stability analysis consist of physical properties, mass movement, and structural geology. Slope stability monitoring with mass movement (displacement) considered to determine the stability of slope wall. Measurable real-time data monitoring provided to reduce risk of unstable slope wall involved with employees, equipment, and economics at the mining environmental. Slope Stability Radar as a monitoring instrument used in several of indonesian open pit mining. Accuration, realibilitation, intensity of SSR monitoring considered very realible to represent " real deformation " of slope wall. On Slope stability Radar data analysis, trend of graphics behaviour is " the key " of monitoring. Combined of trend deformation, velocity and inverse-velocity provide threshold with early warning system purpose. Geology structures fold and thrust fault deleterious stability of slope wall which a lot of case succeed as a " triggers " of failure occurs. By velocity and inverse-velocity rate represent the acceleration of the area with structural geology involved change rapidly. The case study conducted as an effort to help engineer boost " confident " to determine characteristic of failure by the data of slope stability radar and trend particularly with structural geology involved. Variety of graphics characteristic from 15 analysis data purpose to determine " threshold alarm " and proposed as reference on SSR monitoring system for the risk management program at coal mining environmental.

تاکنون روشهای مختلفي بهمنظور تحلیل پایداری شیروانيهای خاکي و سنگي ارائهشده است که
هریک دارای محدودیتهایي بخصوص در محیطهای ناهمگن ميباشند. در این تحقیق بهمنظور تحلیل
شیبهای خاکي و سنگي غیرهمگن که داری ناپیوستگي، درزه و مصالح متفاوت ميباشند از روش
عددی مانیفولد با تحلیل تنشهای موجود استفادهشده که محدودیتهای روشهای سنتي در
محیطهای ناهمگن را ندارد. همچنین بهمنظور تخمین سطح لغزش بحراني و ضریب اطمینان پایداری
از تئوری گراف با الگوریتم بلمن فورد استفاده ميشود. بهمنظور بررسي عملکرد این روش، مطالعه -
موردی با تحلیل پایداری شیرواني سنگي مجاور نیروگاه برقي سیمره مورد ارزیابي قرار گرفت و با نتایج
تحلیل عددی به روش اجزای محدود مورد مقایسه قرار گرفت. نتایج این مقایسه نشان داد که این روش
دارای دقت لازم و کافي است بهطوریکه استفاده از این روش ميتواند برای محیطهای ناهمگن بسیار
سودمند بوده و حجم عملیات مدلسازی و زمان تحلیل را کاهش دهد.

The Infrastructure project of Lusail City in Qatar comprises of; Roads, Underground car park, LRT station, tunnel, Landscape and various utilities. The excavations range from 10 m to 30 m deep (tunnel section), which requires safe angle of slope for constructing cut slope and subsequent remediation in weak strata. The slope stability analyses were carried out and reports prepared to ascertain the stability of cut slopes at various elevations. The designer opted for shotcrete works with rock bolts to stabilize the cut slope wall. Although shotcrete works were being installed, the cut slope wall get collapsed at three different locations, due to excessive pore pressures from the water which comes laterally from the surroundings. After collapse observed, the remediation work was stopped and designer has re-evaluated the factual conditions and redesigned the remedial works. This paper discusses the geotechnical aspects of the soil/rock, design and construction of the excavation and shotcrete works, the analysis approaches employed to evaluate the conditions of the cut slope wall and remedial measures with application of shotcrete works and monitoring to prevent further movement.

An innovative wireless sensor network (WSN) based on Ultra-Wide Band (UWB) technology for 3D accurate superficial monitoring of ground deformations, as landslides and subsidence, is proposed. The system has been designed and developed as part of an European Life+ project, called Wi-GIM (Wireless Sensor Network for Ground Instability Monitoring). The details of the architecture, the localization via wireless technology and data processing protocols are described. The flexibility and accuracy achieved by the UWB two-way ranging technique is analysed and compared with the traditional systems, such as robotic total stations (RTSs) and Ground-based Interferometric Synthetic Aperture Radar (GB-InSAR), highlighting the pros and cons of the UWB solution to detect the surface movements. An extensive field trial campaign allows the validation of the system and the analysis of its sensitivity to different factors (e.g., sensor nodes inter-visibility, effects of the temperature, etc.). The Wi-G...

The increasing attention to the environmental and health impacts of industrial activities by governmental regulations and by the growing awareness level in the society is forcing industrialists to reduce the use of mineral oil-based metalworking fluids as cutting fluid. Cutting fluids have been used extensively in metal cutting operations for the last 200 years. In the beginning, cutting fluids consisted of simple oils applied with brushes to lubricate and cool the machine tool. As cutting operations became more severe, cutting fluid formulations became more complex. There are now several types of cutting fluids in the market and the most common types can be broadly categorized as cutting oils or water-miscible fluids. In this review, the applicability of vegetable oil-based metalworking fluids in machining of ferrous metals has been undertaken. The advantages of metalworking fluids and its performances with respect to the cutting force, surface finish of work piece, tool wear and temperature at the cutting zone have been investigated. It has been reported in various literature that metalworking fluids, which are vegetable oil-based, could be an environmentally friendly mode of machining with similar performance obtained using mineral oil-based metalworking fluids. © 2011 Elsevier Ltd. Allrightsreserved.

http://ac.els-cdn.com/S0890695511001726/1-s2.0-S0890695511001726-main.pdf?_tid=264eeadc-1d34-11e4-ae6e-00000aacb35f&acdnat=1407307234_34c85dbb762d33f91af7172058226f2e 
http://www.sciencedirect.com/science/article/pii/S0890695511001726

With the aim of determining the mechanisms of deformation on fill slopes at the time of an earthquake, 1G shaking table tests were carried out on a saturated model slope focusing on the frequency properties. From the results, it was found that the stability of fill slopes in an earthquake is determined not only by the magnitude of the input acceleration but also strongly depends on the relationship between the natural frequency of the constructed embankment slope and the input frequency. Specifically, the following were concluded. When the input frequency is substantially equal to the initial natural frequency of the slope surface, resonance is produced from the initial stage, and the acceleration is amplified (increase in inertial force). Simultaneous to accumulation of plastic deformation, the mean effective stress is reduced and stiffness decreases. Eventually, the stiffness is lost locally in a shallow part where the confining pressure is small, and slip occurs locally. As the excitation stage increases, the slip extends and expands, and slip occurs in deeper parts. RÉSUMÉ : Dans le but de déterminer les mécanismes de déformation des pentes de talus artificiels lors d'un tremblement de terre, des tests sur table à secousses 1G ont été effectués sur une maquette de pente saturée, en se concentrant sur les propriétés des fréquences. D'après les résultats, on constate que la stabilité des pentes de talus artificiels lors d'un séisme n'est pas seulement déterminée par la magnitude de l'accélération en entrée, et qu'elle dépend également fortement de la relation entre la fréquence naturelle du talus artificiel et la fréquence en entrée. En particulier, nous avons conclu ce qui suit. Quand la fréquence d'entrée est sensiblement égale à la fréquence naturelle initiale de la surface de la pente, la résonance se produit dès l'étape initiale, et l'accélération est amplifiée (augmentation de la force d'inertie). Simultanément à l'accumulation de la déformation plastique, la contrainte effective moyenne est réduite et la rigidité diminue. Tôt ou tard, la rigidité est perdue localement sur une zone peu profonde où la pression de confinement est faible, et un glissement localisé se produit. À mesure que la phase d'excitation augmente, le glissement s'étend et s'accroît, et le glissement se produit sur des parties plus profondes.

Physically based models are commonly used as an integral step in landslide hazard assessment. Geomorphic principles can be applied to a broad area, resulting in first order assessment of landslide susceptibility. New techniques are now available that may result in the increased accuracy of such models. We investigate the possibility to enhance landslide susceptibility modeling by integrating two physically-based landslide models, the Factor of Safety (FS) and the Shallow Stability model (SHALSTAB), with traditional empirical-statistical methods that utilize terrain attribute information derived from a digital elevation model and land use characteristics related to forest harvesting. The model performance is measured by the area under the receiver operating characteristic curve (AUROC) and sensitivity at 90% and 80% specificity both estimated by bootstrap resampling. Our study examines 278 landslide initiation points in the Klanawa Watershed located on Vancouver Island, British Columbia, Canada. We use a generalized additive model (GAM)and a logistic regression model (GLM) combining physical landslide models, terrain attributes and land use data, and GAMs and GLMs using only subsets of these variables.In this study, all empirical and combined physical-empirical models outperformthe physically-based models, with GAMs often performing significantly better than GLMs. The strongest predictive performance is achieved by the GAMsusing terrain attributes in combination with land use data. Variables representing physically-based models do not significantly improve the empirical models, but they may allow for a better physical interpretation of empirical models. Also, based on bootstrap variable-selection frequencies,land use data, FS, slope and plan/profile curvature are relatively the most important predictor variables.

The slope stability evaluation using the generalized Hoek-Brown criterion and regarding the scale effect has been implemented in terms of the Chaarat gold project. Furthermore, the probabilistic assessment and sensitivity analysis are performed. Slope failure probabilities are determined, and the slope stability factors are obtained as functions of the slope height and angle. The slope stability estimation based on classified approach considering the scale effect, including GSI rating and probabilistic analysis is tested in rock slopes. Slope stability is mainly governed by variability of the Geological Strength Index related with the scale effect.

On December 3, 2013, a large complex landslide was triggered SW of the town of Montescaglioso (Southern Italy), causing the destruction of roads, commercial buildings and private dwellings, as well as several direct and indirect economic losses. A set of interferometric ground measurements acquired by the Cosmo-SkyMed satellite constellation and processed by means of the SqueeSAR algorithm was used to study the pre-event slope displacements in the entire Montescaglioso municipal area. Data span from January 30, 2012, to December 2, 2013, and show average line-of-sight velocities of 1–10 mm/year in the slope sector ultimately affected by the collapse. In retrospect, a time series analysis of the radar targets was performed in order to identify and characterize all the slope instabilities in proximity of the town. This was based on the setup of characteristic thresholds of displacement. The procedure permitted to locate several areas which recurrently exceeded these previously established thresholds, in consistency with the amount of precipitation. In particular, the major source of potential hazard in the area was indeed found where the December 3, 2013, landslide eventually occurred. The results of this quick data processing technique were validated through comparison with two independently developed landslide maps. This simple method, which is not supposed to diminish the importance of geo-morphologic field surveys, could improve both the accuracy and the update rate of landslide susceptibility maps. Not relying on arbitrary or empirically derived approaches, it has the advantage of computing statistically based thresholds specific for each time series. By indicating the slope sectors in higher need of deeper in situ investigation, more support could be provided to administrative bodies for the processes of risk assessment and management.