• 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 Society of Environmental Restoration Technology
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• v.8 no.6
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• pp.69-79
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• 2005

This study was carried out to select proper species for early stage replantation in highway cut-slope area. In highway cut-slope area, sample plots of 106 were selected, and their vegetations and environmental factors were investigated. 1. We found total 172 species in the 106 cutting area of highway. The species of high frequency of highway cut-slope were found in the order of Lespedeza bicolor, Artemisia princeps var. orientalis, Festuca arundinacea, Erigeron annuus, Lespedeza cuneata, Lactuca indica var. laciniata, Eragrostis curvula, Dactylis glomerata, Oenothera lamarckiana, Wistaria floribunda, Humulus japonica, Commelina communis, Miscanthus sinensis, Pueraria thunbergiana, Pinus densiflora, etc. 2. The average vegetation coverage was over 90% in the study sites and the average coverage was 91.4% in the total cut-slope area. The species of high coverage of highway cut-slope area were found in the order of Festuca arundinacea, Eragrostis curvula, Lespedeza bicolor, Wistaria floribunda, Lespedeza cuneata, Dactylis glomerata, Artemisia princeps var. orientalis, Humulus japonica, Pueraria thunbergiana, Robinia pseudoacacia, Poa pratensis, Medicago sativa, Festuca ovina, Pinus densiflora, Parthenocissua tricuspidata, etc. 3. The total coverage in the foreign plants of Festuca arundinacea, Eragrostis curvula, Dactylis glomerata, Poa pratensis, Medicago sativa, Coreopsis drummondii and native plants of Lespedeza bicolor, Wistaria floribunda, Lespedeza cuneata, Amorpha fruticosa, Indigofera pseudotinctoria, Lespedeza cyrtobotrya were 57.52%. That is, the ecological succession of native herbs and parachute shrubs have delayed because the afforested plants occupy 57.52%. In future, the coverage of foreign herbs have to reduce, and the coverage of the native herbs and parachute shrubs must be increased. 4. The native seed of Artemisia sp., Miscanthus sinensis, Smilax china, Pueraria thunbergiana, Rubus crataegifolius, Rubus parvifolius, Pinus densiflora, Rhus chinensis, Albizzia julibrissin, Rhododendron mucronulatum, Clematis apiifolia, Zanthoxylum schinifolium, Prunus sargentii could be added in the seedling of the temperate south zone highway with the used seeds. The native seed of Artemisia sp., Miscanthus sinensis, Rubus crataegifolius, Rhododendron mucronulatum, Weigela subsessilis, Stephanandra incisa, Rhus chinensis, Pinus densiflora, Salix koreensis, Cocculus trilobus, Populus alba, Spiraea prunifolia for. simpliciflora, Clematis apiifolia, Lindera obtusiloba, Quercus serrata, etc., could be added in the seedling of the temperate middle zone highway with the used seeds. 5. We have some recommendation. The native plants have to growth in the highway cut-slope area instead of foreign plants to have good environmental ecology. The role of the foreign plants should be the plant for the initial several years in the highway cut-slope area. And, the native plants should growth in the next season. 6. We should protect shrubs and trees in the highway slope area because shrubs and trees can be more helpful in stabilizing of the slope area than herbs.

• Proceedings of the Korean Geotechical Society Conference
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• 2006.03a
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• pp.703-710
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• 2006

The objective of this study is to acquire stabilization of collapse of cut-slope in Chang-Nyung, Gyeong-Nam. The following shows the results of this study. We applied a reinforcement method with the latticed beam $(0.50\times0.50)$ + permanent anchor($PC\;6\times\phi12.7mm$, Ta = 50.0t/EA, etc 3.0m), and fill gravels(D=35cm) in the latticed beam. We attenuated the slope (1:2.0), and stabilized the slope pace by ASANA method. We planned a drainage way(U-type, $0.40\times0.40$) in order to prevent surface water from inflowing into underground.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.878-883
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• 2005

This paper describes the effect of acid rock drainage(ARD) produced from the cut slope on the slope structures. Acid rock drainage is originated from a rock quarry located in coal mine zone and mineralization belt of Chosen Supergroup and Ogcheon group, andesite with the pyrite, and acid sulfate soils of Tertiary in Korea. The cut slope, where acid rock drainage comes out, almost has been constructed by shotcrete and planting works. According to the field observation results, in most cases, the acid rock drainage has an adverse effect on slope structures. The shotcrete, anchors and rock bolts produced corrosive action, and bad germination and growth diseases of covering plants of the slope planting construction due to ARD.

• Tunnel and Underground Space
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• v.11 no.3
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• pp.206-216
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• 2001

Many failures in cut slopes occur during and following road construction. Failures are caused, in part, by a lack of understanding of the characteristics of rock mass including its geologic structure. The stability of rock slopes is closely related to factors that include the type of rock, development of geological structures, weathering, characteristics of rock, and the shape of the geologic features. Therefore, it is very important to consider these characteristics of rock mass in the evaluation of rock slope stability. In spite of investigation from many slope failures, these information data were not systematically stored and not efficiently utilized. In this study, a Database system named DB/SLOPE was developed using Oracle for systematic management of cut slopes. The developed database system can be used to estimate of slope stability and to predict of slope failure.

• Korean Journal of Agricultural Science
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• v.49 no.4
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• pp.809-819
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• 2022

This study was conducted to improve the stability of cut slopes of forest roads in granitic weathered soil areas. The study area is a national forest road (road length 28.48 km) in Pyeongchang-gun, Gangwon-do. After data collection, a statistical analysis was performed using IBM SPSS (Ver. 26.0). First, the correlation analysis showed that structure, slope position, soil erosion, slope, and aspect (N, S) were correlated with vegetation coverage (p < 0.05). Elapsed years, slope distance, and aspect (E, W) were found to have no correlation with vegetation coverage. (p > 0.05) Second, one-way ANOVA and Kruskal-Wallis test results showed that vegetation coverage was worse when the slope was located at the top or the middle of the slope than at the bottom of the slope. In addition, the site with sheathing and gabions showed good vegetation coverage when compared with the site without structures. In the case of soil erosion, areas with severe damage and moderate damage showed worse vegetation coverage. Therefore, it is necessary to strengthen the slope angle of the cut soil of the granitic weathered soil area from 1 : 0.5 - 1.2 to 1 : 0.8 - 1.5. In addition, structures such as sheathing and gabions should be installed on granitic weathered land.

• Tunnel and Underground Space
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• v.6 no.2
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• pp.166-174
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• 1996

Stability of rock slope is greatly affected by the geometry and strength of discontinuities developed in the rock mass. In this study an analytical method which is capable of analyzing the effect of relative orientation between the discontinuities and the slope face on the safety of slope by assessing their vector components was used to evaluate the stability and the maximum cut-angle for the proposed slope design. The results of computerized vector analysis revealed that slope area under investigation might be divided into 3 sections of different face directions. The safety factors for benches in each 3 sections were calculated using the limit-equilibrium theory. Then, by utilizing the concept of probabilistic risk analysis, the susceptibility of entire slope failure was estimated. Based on the distribution of safety factor in each bench, the maximum cut angle of each section could be selected differently ot achieve the permanent stability of the entire slope.

• The Journal of Engineering Geology
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• v.12 no.1
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• pp.53-61
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• 2002

Cut-slope due to the road construction is one of the most significant problems in the domestic case, that is, 70% of the land is covered by mountain. Moreover, typhoons or heavy rains concentrated in summer season causes the failure of cut-slope. Rock-fall and soil slope failure take 40.8% and 29.5% out of the entire domestic cut-slope failure, respectively. Rock-fall is quickly occurred by the free fall or rolling of rock fragments generally in the upper slope. Soil slope failure produces a clastics-flow and increases casualty especially when caused by heave rainfall because the velocity of the movement is verb high. Considering the car speed and rock-fall velocity, it will take a life in a moment. This study analyzes a set of field data of most recently collapsed domestic road cut-slopes to characterize these cut-slopes and the nature of rock-falls and clastics flows at each site. Based on the results, design criteria for a road alarm system are proposed, considering the relationship between the time required for clastics-flow and the velocity and braking distance of a cat at the incidence. The road alarm system proposed herein would operate instantly after a rock-fall and it will minimize damages, by warning drivels approaching to the collapse or collapsing location in advance.

• The Journal of Engineering Geology
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• v.11 no.3
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• pp.303-313
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• 2001

A cut-slope near Guam-Ri Hwado-Eup Namyangju-Si Kyunggi-Do collapsed during a heavy rainfall over 400mm at 28th of August 2000. The cut-slope collapse reportedly developed mainly by block sliding along a set of discontinuities, although slope angle of the cut-slope was 40$^{\circ}$(1:1.2) that agrees with the road construction criteria. This study aims to analyze differences and correlations among several data-collecting methods limited to discontinuity analysis related with cut-slope collapse. This study started with analysing discontinuity surface characteristics, geology of the country rock and orientations of the discontinuities directly related with the collapse. Analysis of aerial photos around the study area provided regional lineament data, and discontinuity plane description and measurements were collected from core logging and Borehole Image Processing System (BIPS). Spearmans correlation ranking coefficient method was used to get correlation of discontinuity planes according to analysis methods. The result suggests that the correlation coefficient is ${\gamma}_s$ = 0.91 Plus, stability analysis of discontinuity plane orientation data using equal-area stereonet revealed that the study area is unstable to planar failure. This study suggests that the cut-slope angles currently applied should be shallower and that significant attention is required to orientation distribution of discontinuities existed in cut-slopes studies.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.6 no.4
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• pp.43-51
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• 2003

The purpose of this study was evaluate to the stability on cut slope of forest roads by forest environmental factors. The total of 19 environmental factors on cut slope of forest roads were investigated in about 42.74km constructed during 1987 to 1993 in Gyeongnam and Jeonnam province. The evaluation of slope stability in forest roads were conducted by the discriment analysis. The main factors influencing the stability of cut slope were significant in order of coverage, soil hardness, degree of slope, altitude, silt loam, convex(凸) and compound(凹凸). The centroids value of discriminant function in the stability and unstability area estimated to -1.194 and 1.127, respectively. The boundary value between two groups related to slope stability was -0.072. The prediction rate of discriminant function for stability evaluation of was as high as 90.4%.