• Journal of Industrial Technology
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• v.26 no.B
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• pp.73-81
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• 2006

A sensitivity analysis about effects of influencing factors on the stability of Soil cut slope was performed. Slope stability analyses were carried out under dry, rainy and seismic conditions. Dominant factors controlling the slope stability were chosen such as cohesion and internal friction angle, unit weight of soil, water table and seismic horizontal coefficient used for the slope stability during earthquake. Parametric stability analysis with those factors was performed for sensitivity analysis. As results of analyzing the sensitivity of factors under dry and rainy conditions, effects of cohesion, internal friction angle and unit weight of soil on the stability of slope are more critical in the dry condition than in the rainy condition. Cohesion and internal friction angle are more dominant factors influencing the slope stability irrespective of dry or rainy conditions than unit weight of soil and the horizontal seismic coefficient. The unit weight and the horizontal seismic coefficient affects crucially the stability according to conditions of slope formation and dry or rainy seasons. For the effect of horizontal seismic coefficient on stability of slope, safety factor of slope is not affected significantly by dry or rainy conditions. However, increase of the horizontal seismic coefficient under the rainy condition floes reduce the safety factor significantly rather than the dry condition. Therefore, it is needed that the location of the water table is assigned appropriately to satisfy the required safety factor of stability in the case of checking slope stability for the rainy and seismic conditions.

• Economic and Environmental Geology
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• v.36 no.4
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• pp.313-320
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• 2003

Slope disaster is one of the repeated occurring geological disasters in rainy season resulting in about 23 human losses in Korea every year. The slope disaster, however, mainly depends on the spatial and climate properties. such as geology, geomorphology, and heavy rainfall, and, hence, the prediction or hazard analysis of the slope disaster is a difficult task. Therefore, GIS and various statistical methods are implemented for slope disaster analysis. In particular, GIS technique is widely used for the analysis because it effectively handles large amount of spatial data. The GIS technique. however, only considers the statistics between slope disaster occurrence and related factors, not the mechanism. Accordingly. an infinite slope model that mechanically considers the balance of forces applied to the slope is suggested here with GIS for slope disaster analysis. According to the research results, the infinite slope model has a possibility that can be utilized for landslide prediction and hazard evaluation since 87.5％ of landslide occurrence areas have been predicted by this technique.

• Journal of Korean Society for Geospatial Information Science
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• v.18 no.4
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• pp.71-77
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• 2010

Cut Slope Management System(CSMS) is a systematic maintenance and management system designed to prevent the collapse of cut slopes located along national roads. In order to implement safe road operation system, KICT has started the inventory of cut slopes and developed a cut slope database since 2006. Cut slope database management system using GIS technology and navigation system was developed as a Information Technology application. Through the Cut Slope Navigation System(SLOPE-Navi.), the previously developed database was checked and verified. The converted cut slope inventory data and field investigation data of 28,707 cut slopes were loaded on the navigation map. We consider that the Cut Slope Navigation Management System can be useful as in-situ system, which can be systematic and effective DB management and operation to prevent cut slope collapses and establish a remedial countermeasure as mitigation concerning disasters.

• Journal of the Korean Geotechnical Society
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• v.21 no.5
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• pp.75-82
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• 2005

Shear strength parameters obtained from field tests are important factors in the analysis of slope stability. In this paper, sensitivity analysis was performed to evaluate the effect of input parameters on the analysis of slope stability. The input parameters selected for sensitivity analysis were slope angle, cohesion, and friction angle. Monte-Carlo Simulation method was to estimate input parameters for sensitivity analysis in slope stability, and the limit equilibrium method was used to calculate the factor of safety of slope stability. A rock slope, failed in the field, was used for the sensitivity analysis of input parameters in the analysis of slope stability. The result of analysis shows that the factor of safety of the rock slope was a little low. From partial correlation coefficient (PCC) of input parameters from the sensitivity analysis, slope stability was dependant mainly on cohesion and slope angle. The effect of friction angle was smaller than those of cohesion and slope angle on slope stability.

• Korean Journal of Environment and Ecology
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• v.11 no.4
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• pp.486-492
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• 1998

The forests of Osaek-Taech'ongbong-Shinhungsa district in Soraksan National Park was studied to investigate forest structure of tree strata in relation to aspect and altitude of the slope. Excepting the main ridge area which has tyoical environmental condition, tree siwe in canopy of the wouthern slope was smaller, density in canopy of the southern slope was higher and species diversity in tree stratum of the southern slope was lower as compared those of the northern slope of same elevation belts. Elevation trend was found for forest structure of the southern slope where geographical features were similar among elevation belts. With incleasing elevation of the southern slope, basal area of canopy and understory increased. With increasing elevation of the southern slope, importance values of Quercus mongolica, Styrax obassia, and Lindera obtusiloba decreased while those of Pinus koraiensis, Betula ercani, Acer tschonoskii var. rubripes and Rhododendron schlippenbachii increased. According to cluster and ordination analysis, the studied forests was classifide into Quercus mongolica community at the low, middle and high elevation belts of the southern slope and the low and middle elevation belts of the northern slope, Betula ermani community at the elevation belt of the northern slope, and Abies koreana community at the top area.

• Journal of the Korean GEO-environmental Society
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• v.8 no.4
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• pp.67-74
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• 2007

Many studies for slope stability studies have indicated that the infiltration of rainwater into a slope decrease the slope stability. In order to minimize damage caused by slope failure, most design codes suggest that the slope stability be analyzed by saturated condition during rainy season. However it would be excessively conservative condition that every soil slope is saturated in rainy season irrespective of rainfall intensity, soil type and slope geometry. In addition, because most soil slopes are in an unsaturated state, it is necessary to consider the unsaturated characteristics of slope. This paper suggests a prediction method of saturation time for the weathered granite soil slopes due to rainfalls. The finite element analysis of transient water flow through unsaturated slope was used to investigate effects of soil-water characteristics, permeability at saturation, slope geometry, and rainfall intensity. From the result of these analyses, the prediction charts considering soil-water characteristics, permeability at saturation, and slope height were proposed in this study. It is possible to the time required to be saturated slope after rainfall.

• Journal of the Korean Geosynthetics Society
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• v.17 no.4
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• pp.11-19
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• 2018

Although many researches related to monitoring and automatic measuring devices for early warning system during slope failure have been carried out in Korea and aboard, most of the researches have installed measuring devices on the slope surface, and there are only few researches about warning systems that can detect and warn before slope failure and disaster occurs. In this study, slope failure simulation experiment was performed by attaching sensors to rock bolts, and initial slope behavior characteristics during slope failure were analyzed. Also, the experiment results were compared and reviewed with varied slope conditions, i.e. shotcrete slope and natural slope, and varied material conditions, i.e. GFRP and steel rock bolt. This study can be used as a basic data in development of warning and alarm system for early evacuation through early detection and warning before slope failure occurs in steep slopes and slope failure vulnerable areas.

• Journal of Biosystems Engineering
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• v.30 no.1 s.108
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• pp.1-7
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• 2005

When a slope tractor works on the slope land, it travels usually along the contour and slope line. In that case, the efficiency of work generally decreases and the safety of the operator caused by the overturn of the tractor should be considered. Maintaining the tractor body being horizontal during the travel is crucial to solve problems. To overcome such a problem, an automatic leveling control system for slope tractor has been developed. The system composed of sensor for measuring rolling and pitching inclination of the slope tractor chassis, controller, hydraulic control system and mechanism. The limit angle of the leveling control was set up to be ${\pm}15^{\circ}C$ for rolling, ${\pm}7^{\circ}C$ for pitching. The proposed control and hydraulic power system was implemented to the prototype slope tractor. This paper shows results about development of the automatic leveling mechanism and response properties for slope tractor.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.10 no.4
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• pp.83-94
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• 2007

Test application of revegetation measure was made on the roadside slope damaged by Gimcheon-Eomo national road improvement project in a bid to prevent the soil from being washed out as well as to restore the ecological environment, and the survey for assessing the effect of slope revegetation measures was conducted, beginning Sep 7 through Sep 20, 2006. In the wake of comprehensive reviewing and evaluating the surrounding topographic environment, physical and chemical characteristics of soil, germination of revegetation plants, analysis of bio mass, covering ratio and the plants appeared, revegetation measure C was found to have been most effective and desirable for further application in the area. Viewing the specific applicability by the area, revegetation measure C and C-1 appeared to be appropriate for blasting rock slope and ripping rock slope as they are efficient in preventing the slope from being washed out and in early revegetating. And revegetation measure B deemed to be effective to blasting rock slope or ripping rock slope as an alternative. And for cut slope, vegetation measure C-2 was judged to be more effective than measure D or E, while measure C-3 would be appropriateto embankment slope.

• Journal of Forest and Environmental Science
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• v.30 no.1
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• pp.71-75
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• 2014

Forest roads failure is one of the most common problems caused by heavy rainfalls. This study investigated the characteristics on stabilization measures installed for cutting slopes failure of forest road resulted from heavy rainfalls. Three primary factors (slope length, slope gradient, soil type) affecting cutting slope failure were considered and stabilization measures were classified into two types (A type: wooden fence, vegetation sandbag, stone masonry; B type: wire cylinder, gabion, concrete retaining wall) through discriminant analysis based on their capacity of resistance to slope failure. Results showed that A type was mainly installed in such conditions as cut slope <8 m, cut slope gradient $30-40^{\circ}$ and soil type with soil while B type occurred in locational conditions as cut slope length >8 m, cut slope gradient < $30^{\circ}$ and > $30^{\circ}$, and soil type of gravelly soil and rock.