• Geomechanics and Engineering
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• v.23 no.3
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• pp.289-300
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• 2020

With the rapid development of the distributed strain sensing (DSS) technology, the strain becomes an alternative monitoring parameter to analyze slope stability conditions. Previous studies reveal that the horizontal strain measurements can be used to evaluate the deformation pattern and failure mechanism of soil slopes, but they fail to consider various influential factors. Regarding the horizontal strain as a key parameter, this study aims to investigate the stability condition of a locally loaded slope by adopting the variable-controlling method and conducting a strength reduction finite element analysis. The strain distributions and factors of safety in different conditions, such as slope ratio, soil strength parameters and loading locations, are investigated. The results demonstrate that the soil strain distribution is closely related to the slope stability condition. As the slope ratio increases, more tensile strains accumulate in the slope mass under surcharge loading. The cohesion and the friction angle of soil have exponential relationships with the strain parameters. They also display close relationships with the factors of safety. With an increasing distance from the slope edge to the loading position, the transition from slope instability to ultimate bearing capacity failure can be illustrated from the strain perspective.

• Geomechanics and Engineering
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• v.13 no.4
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• pp.571-584
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• 2017

Slope mass rating (SMR) is commonly used for the geomechanical classification of rock masses in an attempt to evaluate the stability of slopes. SMR is calculated from the $RMR_{89-basic}$ (basic rock mass rating) and from the characteristic features of discontinuities, and may be applied to slope stability analysis as well as to slope support recommendations. This study attempts to utilize the SMR classification system for slope stability analysis and to investigate the engineering geological conditions of the slopes and the slope stability analysis of the Gas Flare site in phases 6, 7 and 8 of the South Pars Gas Complex in Assalouyeh, south of Iran. After studying a total of twelve slopes, the results of the SMR classification system indicated that three slope failure modes, namely, wedge, plane and mass failure were possible along the slopes. In addition, the stability analyses conducted by a number of computer programs indicated that three of the slopes were stable, three of the slopes were unstable and the remaining six slopes were categorized as 'needs attention'classes.

• Journal of Ocean Engineering and Technology
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• v.20 no.5 s.72
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• pp.49-56
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• 2006

In this thesis, centrifuge model experiments and numerical analyses were carried out to investigate the behavior of an excavated slope in soft clay ground. Centrifuge model tests were performed with various slopes for the excavated ground, such as 1:1.5 and 1:2. Pore pressuresthe model ground were measured to find their effects on the stability of the excavated slope. These experiments showed that the model with 1:2.5 maintained its stability within a short period of time and failed gradually. Therefore, anexcavated slope of soft soil with this slope might maintain stable conditions within a certain time. The mode1 with a 1:3 slope was observed to maintain a very stable condition, showing insignificant deformation in the ground after being excavated. Numerical analyses with PLAXIS, a commerciallyavailable software implemented with the finite element numerical technique, were performed to find the pore pressure distribution within the ground mass and the deformation of the soil. From the results of numerical analysis, a negative pore pressure was developed after the excavation and thus the stability of the slope was maintained. The safety factor for slope failure was found to decrease with time because of the dissipation of negative pore pressure with time.

• The Journal of Engineering Geology
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• v.4 no.3
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• pp.343-356
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• 1994

When most of the industry and social indirect facilities such as the large structure, power plant or road, rail-road are constructed, the new slope may lead to the slope failure. The failure models for slopes have been developed by using the results of in-situ and laboratory tests to investigate the mechanisms and types of the slope failure. The safety factor of a slope may be obtained based on the proposed model and the slope can be reinforced to meet the design criteria. The slope should be reinforced by using the optimum model that properly reflects the site condition, the method of reinforcement includes the increased safety factor either by decreasing a slope angle or by reinforcing the slope.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.03a
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• pp.419-426
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• 2008

Recently, localized heavy rain due to "EL-LIO" was a kind of reason by risk of slope stability. In this paper, the behaviour of slope when localized heavy rain was studied. In order to perform this study experimental programs were performed. Experimental programs was checked filtering conditions for slope stability due to localized heavy rain. And then, investigated slope stability and fracture mechanism each other types. In the experimental study, performed changing filtering condition by embankment, through five fixing factors such as rainfall intensity, slope shape, geological condition, compaction energy and water content. According to the results of this study, behaviour of facture slope has made a shallow and narrow waterway. This waterway expanded base stone. In order to, suggested a system for slope stability examination.

• Journal of the Korean Geotechnical Society
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• v.31 no.5
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• pp.47-58
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• 2015

Triggering rainfall and geologic conditions with the state of slope hazard were investigated based on the field investigation and collected data on the slope hazard during the period between 2011 and 2014 in Korea. Analysis results showed that most of slope hazards occurred in metamorphic rock and debris flow was the most frequent type of slope hazard. Slope hazard increased when the higher monthly mean rainfall was recorded. However, most of slope hazard occurred when certain time elapsed after the moment of maximum hourly rainfall. Finally, more than one month of long-term rainfall was shown to be related to the frequency of slope hazard in the period.

• Magazine of the Korean Society of Agricultural Engineers
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• v.39 no.1
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• pp.112-121
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• 1997

The aim of this study was to analyze the slope stability relating to the failure of cut slopes and the characteristics of stress-strain relations obtained by limit equilibrium method, finite element method, and stereographic projection method for the reinforced cut slopes. The following conclusions were made : 1.To use stereographic projection method led to little possibility to take the toppling and wedge failure while to use the other methods led to the failure. It was recommended to reduce the slope inclination from 1:1 to 1: 1.5~1 :1.8 and adopt coir mesh method to protect the slope surface. position with the horizontal displacement after final excavation moved to the excavation base. The maximum shear strain values concentrated at the excavation base indicated the possibility to induce the local failure. 3. It was recommended that the slope inclination for blast rock with the slope height larger than l0m was 1: 0.5, 1:1, and 1: 1~1 :1.5 for hard rocks, soft and ordinary rocks, and ripping and soils, respectively. 4. Berm width criteria for blast rock with the slope height larger than l0m were recommended as follow : 2~3m per 20m slope height for hard rocks, 1 ~2m per l0m slope height for soft and ordinary rocks, 1 ~ l.5m per 5m slope height for ripping and soils.

• Journal of the Korean Institute of Landscape Architecture
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• v.20 no.3
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• pp.33-43
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• 1992

The perceptual characteristic on the slope scenery around highway is very similar as the general perceptual characteristic in the landscape. This process determines by the relationship between the scenery observers and the characteristics of its place. It is very important to have a analysis on highway slope scenery in our particular culture in Korea since our country's highways are done by cutting mountains : therefore, we have a lot of slopes around highways. The physical characteristics on the highway scenery determines how we should build scenery around highway to a satisfactory level. The results drawn from this research work are as follow: 1) The satisfaction for slope scene had been affected by sex, native and experience of travel. I thought that the slope scene having peculiar form will offer the highest satisfaction. 2) Psychological factor, reflected satisfaction of slope scene, 몽 a grip of three factors as the factor of evaluation, texture, formation, and presumption formula is : Satisfaction=1.04(Evauluation factor)+0.83(Texture factor)+0.15(Formation factor)+4.28)R2=0.69). 3) Vine among the vegetation componeents of slope scene highly correlated with the evaluation factor and grass, shrub correlated with the texture factor. 4) Rock among the structual components of slope scene highly correlated with the formation factor, and stockade, lattice correlated with the evalution factor. 5) Gradient among the properties which determined slope form, highly correlated with the formation factor.

• Geomechanics and Engineering
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• v.6 no.6
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• pp.561-575
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• 2014

Estimating seismic displacements has a great importance for foundations on or adjacent to slope surfaces. However, dynamic solution of the problem has received little attention by previous researchers. This paper presents a new analytical model to determine seismic displacements of the shallow foundations adjacent to slopes. For this purpose, a dynamic equilibrium equation is written for the foundation with failure wedge. Stiffness and damping at the sliding surface are considered variable and a simple method is proposed for its estimation. Finally, for different failure surfaces, the calculated dynamic displacement and the surfaces with maximum strain are selected as the critical failure surface. Analysis results are presented as curves for different slope angles and different foundation distances from edge of the slope and are then compared with the experimental studies and software results. The comparison shows that the proposed model is capable of estimating seismic displacement of the shallow foundations adjacent to slopes. Also, the results demonstrate that, with increased slope angle and decreased foundation distances from the slope edge, seismic displacement increases in a non-linear trend. With increasing the slope angle and failure wedge angle, maximum strain of failure wedge increases. In addition, effect of slope on foundation settlement could be neglected for the foundation distances over 3B to 5B.

• Geomechanics and Engineering
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• v.33 no.2
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• pp.167-174
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• 2023

This study evaluated slope stability through a case study to determine the disaster risks associated with increased deforestation in structures, including schools and apartments, located in urban areas adjacent to slopes. The slope behind the ○○ High School in Gwangju, Korea, collapsed owing to heavy rain in August 2018. Historically, rainwater drained well around the slope during the rainy season. However, during the collapse, a large amount of seepage water flowed out of the slope surface and a shallow failure occurred along the saturated soil layer. To analyze the cause of the collapse, the images of the upper area of the slope, which could not be directly identified, were captured using unmanned aerial vehicles (UAVs). A digital elevation model of the slope was constructed through image analysis, making it possible to calculate the rainfall flow direction and the area, width, and length of logging areas. The change in the instability of the slope over time owing to rainfall lasting ten days before the collapse was analyzed through numerical analysis. Imaging techniques based on the UAV images were found to be effective in analyzing ground disaster risk maps in urban areas. Furthermore, the analysis was found to predict the failure before its actual occurrence.