• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.1050-1056
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• 2008

Many cut slopes are situated on national highways. In this study, we chose rock slopes of moderated weathering grade to analyze general strength parameters of cut slopes. We analyzed the strength parameters of selected rock slopes by the experience method. Also, we arranged the strength parameters by area and rock types.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.6 no.6
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• pp.72-85
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• 2003

The purpose of this study is to establish the basis of the ecological restoration on the limestone mines in Korea, through the research of the revegetation measures of the disturbed slopes in Japanese limestone mines and the analysis of the case of Ibuki and Bukou limestone mines to realize the restoration works successfully. According to the number of mines to carry out the revegetation works increase every year, the revegetation area and amount of planting also go on increasing in Japan. In the small mines the environmental problem is not recognized seriously, but some mines have muchly invested in the revegetation of the damaged land by mines. Ibuki mine in Shiga-gen is practicing the four principles for the restoring of the revegetation in the disturbed slopes by mines. Firstly, the mean slope preserves $37^{\circ}$ in the last rock cut slopes. Secondly, the last rock cut slopes to rehabilitate are covered with the soil dressing 30cm high. Thirdly, the grasses in the mining area are digged up beforehand, and then they are reused to the revegetation works of rock cut slopes. Lastly, from the upper rock cut slopes the revegetation works begin, the process of the above are repeated, as the result, the restoring works will be completed. Upon the ground of these principles, the complex of the original vegetation and the native species seeding, that is, the revegetation technique of Ibuki have established. In the difficult area to revegetate, sodding works, heaping up vegetation-sack, seed-spraying, heaping up soil-sacks and planting works are adapted variously. Bukou mine in Saitama-gen try to maintain the revegetation, the screening and the stability of the enormous mining rock cut slope, and for these works, the activity of 'Chichibu Working Group of Rock Wall for Limestone Mines' contributes largely. The chief technique of the revegetation in Bukou mine is following; after the making the berm on the rock cut slopes, the soil dressing is filled in it, and the trees is planted for the screening of the rock cut slopes. They devide the rock cut slopes into four typical types, and choose the different ways to make the berm and fill the soil dressing in characteristic. Most of the planting trees are consist ofthe native species of Mt. Bukou through the stages of the nursery and transplantation. Not only the revegetation of the demaged land but also the breeding of the conservational plants also are their important business.

• Proceedings of the Korean Geotechical Society Conference
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• 2006.03a
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• pp.652-661
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• 2006

The cut slopes in Jinju area constitute the Cretaceous Sedimentary rock which is one of the most poor ground conditions. The geological rocks of the cut slopes are correlated with Jinju Formation. Most of the rocks consist of Black Shale layer, but the lower parts consist of Alkorsic White Sandstone. So, It is characteristic of the differential weathering due to the difference of rock species. Moreover, vertical joints which concentrate on the released rock and weak rock fragments are accompanied with minor faults. We make out face mapping about each slopes through the detailed field-study and deduce RMR and SMR from the field data. The strength properties of rocks were obtained from references, indoor tests, and Back Analysis method. And, choosing properties were used in the stability analysis as stereographic projection and limit equilibrium analysis and we establish the countermeasures for the cut slopes.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.2 no.4
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• pp.64-73
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• 1999

This study was conducted to find out the effects of hydroseeding material and seed mixture on the revegetation of rock cut-slopes by PEC4 (Polymer-Ecology-Control) Hydroseeding Measures. PEC4 hydroseeding material was applied to four cut-slopes using hydroseeding measures from April to August, 1999, and the field survey was carried out by monthly. PEC4 material consisted of bark compost and organic soil amendments. This material has high content of organic matter and high level of water holding capacity. PEC4 hydroseeding material shows low level of soil hardness, so it gives to good condition for seed germinating and plant growing in early stage. PEC4 material attached at rock cut-slopes by two types of adhesive agent was not eroded by rainfall. The plant coverage and number of plant species were affected by mixing ratio of seeds and seeding timing. From the viewpoint of plant establishment, the optimal hydroseeding timing of mixed seeds for plant growth seems to be in May. Most of the plant seeds were germinated well and they covered rock cut-slopes so quickly and effectively. Plant importance value of Silene armeria and Platycodon grandiflorum. were higher than any other seeded-native species in the competition between native species and exotic species, so they have enough possibility to be used for slope revegetation works. Thus it leads to conclusion that the revegetation method used in this experiment was a very effective method for plant establishment on rock cut-slopes.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.5 no.4
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• pp.70-79
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• 2002

This study was conducted to develop environmental restoration methods for the ecological restoration of the rock exposed steep cut-slopes using native woody plants seeds by the hydro-seeding with artificial soil media. The main results are summarized as follows; 1. Quercus spp. seeded after seed treatment germinated over 80% and most of them grew well until one year. So, Quercus spp. can grow at the extremely dry rock exposed slopes revegetated by hydro-seeding with soil-fertilizer-seed mixed media. 2. The germinated seedlings grew well at the slopes oriented southeast. But in case of the survival ratio of the germinated seedlings, northwestward slopes was the best. 3. In case of the using pot seedlings of the Miscanthus sinensis var. purpurascens, it shows more beautiful scenery than the area using cool-season grasses. 4. As the results of the experiment, Albizzia julibrissin, Quercus spp. and Lespedeza crytobotrya can be useful at the restoration and revegatation of the cut-slopes. 5. At the results of the seed mixture experiment, cool-season grasses covered the ground quickly, but slowly germinated Quercus spp. and Lespedeza crytobotrya formed under story vegetation. Also, Albizzia julibrissin formed upper story vegetation will be replaced by Quercus spp. slowly.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.09a
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• pp.1274-1281
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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 and to minimize damages caused by slope collapse related accidents. In order to implement a maintenance and management system that will ensure safe road operation, the Korean government has started the inventory of cut slopes and developed a cut slope database since 2006. The study on the application of cut slope database is on-going and part of this study is the development of cut slope database management system (Slope-navi) using GIS technology and navigation system for the effective and efficient cut slope management using Information Technology. Using the Navigation Cut Slope Data Management System the previously developed database was checked and verified. The converted cut slope inventory data and field investigation reports of about 20,000 cut slopes were loaded in the navigation map. Through the development of the navigation's cut slope data search system, a systematic and efficient cut slope database management and operation in the prevention of slope collapse and remedial measure selection was established.

• Journal of Korean Society for Geospatial Information Science
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• v.18 no.4
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• pp.87-92
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• 2010

With recent localized heavy rain, the collapsing accident of the cut slopes occur repeatedly every year. The maintenance of the cut slopes is very crucial as the collapsing of cut slopes causes various calamities such as human causalities and sweeping away of the roads. By looking at the study of current situation of the cut slopes, designed for maintenance of cut slopes, the locations of the damaged districts are hard to figure out as they are represented through distance mark and longitude and latitude. In this paper has used NDGPS methods and VRS service through GPS signal corrections that are received by DGPS standard department to correctly analyze the exact location and the shape of the slope. The result of this analysis shows that both methods produce similar shape of the slope. Therefore, these two methods, NDGPS methods and VRS service, can be applied to other analysis of cut slopes in different areas.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.862-869
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• 2005

This study examined 233 cut slopes in Gyeongnam region; evaluated hazards and slope conditions involved in the slope; and determined the priority order for reinforcement. The conclusions are summarized in the following. (1) The slopes that need reinforcement or maintenance are 153, accounting for 65.6% of the entire slopes. Slopes with a length of $0{\sim}200m$ account for 70.9%; slopes with a height of $10{\sim}20m$ account for over 50%. (2) Slopes with slope of more than 1:0.5 account for 70.9% of the entire slopes. The steepness of the slope is owing to more rock slopes than soil slopes. (3) The percentages of rock slopes, soil slopes, complex slopes mixed with rocks and soil, and slopes comprised of igneous rocks are 54.4%, 24.9%, 20.7%, and 54.1%, respectively. (4) In the rock area occurred cave-in, plain failure, wedge failure, and overturning failure, in order. Slopes with volcanic rocks are the most unstable, while sedimentary rocks and metamorphic rocks are relatively stable. (5) When the slope height is over 20m, low grade slopes are more than 80%; leading to the conclusion that the higher the slope height is, the more unstable the slope is.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.19 no.6
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• pp.63-76
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• 2016

Slope revegetation refers to the use of vegetation and construction to protect a barren slope devastated by road and building construction. Among many revegetation strategies, hydroseeding has been widely utilized to stabilize barren slopes and has become the representative approach. Previous studies on slope stability have been conducted from a civil engineering perspective, mainly evaluating the stability of cut-slopes on solid bedrock and the use of concrete structures to stabilize devastated slopes. This study was conducted to develop a method to evaluate erosion risk of revegetated cut-slopes, based on criteria derived from previous studies. Twenty-five factors were surveyed on both on-the-spot erosion slopes and non-erosion slopes after slope revegetation to compare slope types. The scores of all non-erosion slopes exceed 80 score while erosion slopes are 80 below. Erosion slopes got the range of 68-74 score while non-erosion slopes got the range of 81-100 score in the first result which was not applied for weighted-values. The scores of all non-erosion slopes exceeded 3.10, while erosion slopes were below 3.10. Erosion slopes were in the range of 2.73-3.09, while non-erosion slopes were in the range of 3.15-3.90 in the second result, which was applied with weighted-values according to the AHP result from a previous study.

• Journal of the Korean GEO-environmental Society
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• v.8 no.3
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• pp.51-57
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• 2007

In the design of slopes during rainfall, the groundwater level is assumed to be located at the ground surface, based on the change in characteristics of rainfall. In addition, stability investigations are performed for large cut slopes in the design of slopes while standard inclinations specified in the design criteria are applied for the slopes that stability investigations are not performed. In spite of the strengthened criteria of groundwater location, slope failures continuously occur during heavy rainfall, regardless of magnitude of slopes. In order to investigate the cause of the failures, stability investigations have been performed on standard inclination of slopes suggested in the design criteria for both dry and rainfall cases by ground condition in this research. Despite that standard inclination of slopes specified in the design criteria should be stable for both dry and rainfall cases, the results show that standard factor of safety has not been obtained in many cases; more than 50% of total cases for dry cases and more than 65% of total cases for rainfall case. Based on the results, this paper indicates the problems in the current design criteria and proposes the plans for establishment of countermeasure.