• Proceedings of the Korean Geotechical Society Conference
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• 2009.03a
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• pp.1161-1170
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• 2009

The Roads in Gangwon Province generally was made on purpose to use the military road. In case of these roads, tremendous dangerous cut slopes do exist and its road linear shape was badly designed. In order to make up for this situation, the government has continuously established the new road or performed the public works such as the straight line of the curved road. Soksil 2 cut slope was made through the road improvement work. This has small surface failures and collapses. In spite of dry season, this slope are leaking lots of groundwater at the unbelievable point. So as to get curious phenomenon right, we performed a detailed field investigation, the geomorphological analysis, the stability analysis considering field characteristic and ultimately proposed the countermeasure to make sure stability of Sokil 2 cut slope.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.966-973
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• 2008

In recent, the collapses of cut-slope is gradually increased due to the heavy rains accompanied by typhoon. Specially, many cut-slope failures and landslides was happened to Goheung, Yeosu, Suncheon region, Jeonranamdo in the middle of September 2007. The slope of investigation is width 20 m, height 22 m, and the circular failure was occurred. The parent rocks of the slope are pyroclastic rock, namely andesite, andesitic tuff et al. and the weathering grade is completely weathered to residual soils owing to rapid weathering process and has the existence of fault zone and mafic dyke. Also, lots of extension cracks are presented and the hydrologic condition is very deteriorated. As a result of the limit equilibrium analysis, the safety factor is 1.09(in dry season) and 0.64(in wet season). For the stabilization of the cut-slope, we decided to use the retaining wall, anchors and drainage apparatus.

• Korean Journal of Agricultural Science
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• v.6 no.2
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• pp.166-184
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• 1979

In order to prevent the water loss in the irrigation canal constructed on the sandy gravel layer or on the other highly permeable ground layer, lining has been practiced. Many studies have been done so far on the lining method to prevent the water loss in the irrigation canal and recently studies on the lining with plastic film or polyethylene film were also reported. However, the plastic film or polyethylene film has low strength and is liable to break, and water loss from pin hole caused by contacting with sand or gravel is highly predicted. This study was then conducted to find proper lining and buring method in canal construction of polypropylene mat after coated with vinyl, as one way to overcome the shortcoming frequently observed when plastic or usual polyehtylene film were used. Eventhough rather longer periods of experiments are needed to attain reliable and accurate results on the variation of durability, the durability of asphalt coated area, or on the damage due to freeze after burial or exposure of polypropylene mat, the experiemental results obtained during one year of period are summarized as follows: 1. The curvature at the area between canal bottom and side slope had increased stability and saved consruction cost. The relationship among the variation of curvature, the reduction of polypropylene mat and the reduced amount of soil cutting at each side slope was presented in Fig. 7 through 9. 2. The depth of covering material to protect polypropylene mat was desired to be over 30cm, considering the water depth, side slope, canal cleaning practices, traffic, or back pressure of irrigation period. 3. In order to increase the canal stability and to prevent slope erosion, sandy soil was required, to be placed under ground, and coarse gravel should cover the surface area of canal. 4. The studies on the stability of side slope in the canal should consider the passive area on the bottom and the slope should be about 1 to 2, considering the slope stability, allowable velocity and tractive force. 5. When compared with earth lining, the lining with polypropylene mat coated with vinyl was responsible to save 28% and 37% of canal lining cost, when the soil carrying distances were 500 and 700m. respectively. 6. The water interception was almost completely attained when the polypropylene mat coated with vinyl was used for lining. But further studies were assumed to be necessary for the use of asphalt since the strength of polypropylene mat connected with asphalt will vary with duration.

• Journal of the Korean Geotechnical Society
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• v.28 no.1
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• pp.5-15
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• 2012

This paper presents the results of an investigation into the pull-out characteristics of screw anchor piles for use in braced excavation and cut-slope. A series of reduced-scale model tests were performed on model screw anchor piles with different geometric characteristics such as screw size and pitch length. The results indicated that the pullout resistance increases with decreasing the pitch length for a given screw size. It was also observed that the pullout capacity of a screw anchor pile increases with the screw size up to a certain size beyond which the increase becomes minimal. The results are presented in such a way that the pullout characteristics of screw piles with different screw geometric characteristics can be identified. Practical implications of the findings are discussed.

• Journal of the Korean Geosynthetics Society
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• v.12 no.1
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• pp.101-107
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• 2013

Environmental-friendly and economical construction are the recent issues for civil structures and soilbag as facing wall is widely used for cut-slope remediation projects. However, the stability of structures is an important issue for the use of environmental-friendly and economical materials. In order to understand the stability of soilbag reinforced retaining wall, tensile resistance, rupture, tensile strength, and internal/external safety factor of the wall were analyzed with MSEW program and the results were compared to the safety factor of block-type reinforced walls. The stability of retaining wall was analyzed with reduction coefficients of connection strength to check the connection stability. Because it is possible to move between soilbag and geogrid connector for soilbag retaining wall, the safety factor of the wall was analyzed with different inclination angles of soilbag. The analysis result shows that the connection strength and internal/external stability of soilbag reinforced wall satisfy the stability criteria.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.1 no.1
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• pp.63-69
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• 1998

The slope revegetation methods in Korea are generally the hydroseeding mixed with perennial herbs, soil, fibers, and fertilizer in consideration of scenic landscape rather than ecological and engineering effect. But perennial herbs can't protect the slope from deep surface erosion and they are not tall enough to create the original naturalness at the boundary parts of existing woodlands. This study is about the slope revegetation method using nutritional propagation capacity of plants and the experimental construction was carried out on the cut-slope of Yongin Hoam C.C. We dug several trenches to a depth of 80cm and at intervals of 150cm from each other. After placing various kinds of live branches(Salix species) into the trench, we backfilled with the excavated soils and finally sprayed water mixed with soil-stabilizer, fertilizer. As six months passed, we made a vegetation research and check the slope surface erosion. Vegetation research was performed in examining the frequency of each block using transect method. 31 kinds of plant species appeared in total area($113.6m^2$) and the dominant species are Setaria viridis, Artemisia rubripes, Persicaria pubescens, Plantago asiatica, Cyperus amuricus, Commelina communis. Among the examined blocks, '아', the top part of the slope, showed the ratio of 1.4 as the highest Alpha-diversity. With regard to life form, therophytes were shown dominant distribution of 58% of total species and neophytes relatively low distribution of 16%. It can be estimated that there is no ecological stabilization of this slope, because of ruderal species' occupation of 74% in total area. Regarding the slope stabilization, the serious surface erosion didn't take place in spite of heavy rainfall this year, but a little surface erosion took place at the block where no other species coming from outside of the site were found.

• Journal of the Korean GEO-environmental Society
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• v.20 no.1
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• pp.35-42
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• 2019

Various development works inevitably increase cutting slopes due to land use, and many of trails managed by different authorities are being deteriorated by long-term weathering. Collapse of slopes causes unavoidable damage of property and loss of lives because of its uncertainty and difficulty in predicting its occurrence. In order to overcome the unavoidability, America, Japan, and several European nations analyze the kinetic energy and moving distance when rocks of upper slope move along the inclined plane, via field tests and computerized interpretation of the test results. Also, they are making efforts to develop measures with which the kinetic energy of the rocks moving along the slope is absorbed and fails to reach to specific structures. However, domestic researches just focus on fragmentary prediction of rockfall using existing programs, and there have been few approaches to identify interpretation methods appropriate for domestic cases or determination of parameters. In this context, we in this study defined rockfall types and affecting factors and analyzed effects of parameters using a general-purpose rockfall simulation program to understand principles of rockfall and to estimate effects of various parameters.

• Proceedings of the Korea Water Resources Association Conference
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• 2021.06a
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• pp.19-19
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• 2021

최근 드론 및 ICT 융·복합기술은 산업 전반에 걸쳐 새로운 대안을 제시하고 있으며, 종전의 산업은 데이터 생성·가공·활용의 효율성, 경제성, 안전성 등의 장점을 들어 빠른 속도로 관련 ICT와 의 접목을 시도해 왔다. 이를 통해 과거의 기술과 방식에서는 찾아보기 힘들었던 다양한 형태의 결과물을 제시하는 등 데이터 기반의 4차산업혁명이 선도하는 변화가 곳곳에서 일어나고 있다. 국토교통부에서는 2018년부터 중앙·지자체·공공기관 소속직원을 대상으로 드론 조종인력 양성사업을 시작으로 2019년 국방·치안·환경·안전·측량 등 10개 분야에 드론 활용 임무특화교육을 진행해왔으며, 2020년도에는 시설물 점검, 불법행위 추적 감시, 수자원 관리 등으로 교육 분야 추가하는 등 활용범위를 확대해나가고 있다. 경기도 안전관리실(안전특별점검단)에서는 이러한 국가정책의 방향에 맞춰 새로운 기술과 융합을 시도하고자 2020년부터 '드론 등을 활용한 시설물 안전점검 고도화 연구'를 시작으로 절토사면 및 옹벽 등 시설물 안전점검과 하천 및 우수저류지의 유지관리에 ICT 융·복합 기술 및 분석용 S/W 등을 적용하고자 하였다. 본 연구에서는 드론 및 LiDAR 등을 활용하여 하천, 배수로, 우수저류지 등에 대해 공공관리주체가 실시할 수 있는 유지관리점검 및 현황분석 방법에 관한 것으로서 「하천법」, 「자연재해대책법」, 「시설물의 안전 및 유지관리 실시 세부지침」, 「우수유출저감시설의 종류·구조·설치 및 유지관리 기준」 등에서 정한 사항에 대해 적용하였다. 이를 통해 하천, 우수저류지 등 수공구조물의 홍수위 변동성 평가, 홍수조절부 용량검토 등 홍수방어 능력에 대한 유지관리 차원의 공공관리주체 역할을 강화하는 제도적 측면을 검토하고, 드론, LiDAR 등의 ICT 융·복합 기술 활용 확대를 통해 예산절감 및 공공안전 강화에 기여할 수 있을 것으로 판단된다.

• Journal of the Korean GEO-environmental Society
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• v.16 no.12
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• pp.53-58
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• 2015

Engineers should take great care of characterizing the engineering properties of mudrock, because the uncemented mudrock can be considered as a hard rock in appearance. Therefore, the mudrock samples obtained from the cut slope in Gyeongki-do were tested to evaluate the strength characteristics of uncemented mudrock in this study. The performed tests are index properties, slake durability, and swelling tests for the classification of the mudrock for engineering practice. To evaluate the effect of water on the engineering properties of the uncemented mudrock, resonant column, triaxial compression and direct shear tests with various water contents were performed. With the increasing water contents, stiffness at very small to small strain region and the cohesion value of the strength parameters decrease. Based on the test results, engineers should take great care of evaluating the engineering properties of uncemented mudrock.

• Journal of the Society of Disaster Information
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• v.20 no.2
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• pp.270-283
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• 2024

Purpose: Considering the rising frequency of earthquakes in Korea, it is crucial to revise the rainfall thresholds for landslide triggering following earthquake events. This study was conducted to provide scientific justification and preliminary data for adjusting rainfall thresholds for landslide early warnings after earthquakes through soil physical experiments. Method: The study analyzed the change in soil shear strength by direct shear tests on disturbed and undisturbed samples collected from cut slopes. Also, The study analyzed the soil strength parameters of remolded soil samples subjected to drying and wetting conditions, focusing on the relationship between the degree of saturation after submergence and the strength parameters. Result: Compaction water content variation in direct shear tests showed that higher water content and saturation in disturbed samples led to a significant decrease in cohesion (over 50%) and a reduction in shear resistance angle (1~2°). Additionally, during the ring shear tests, the shear strength was observed to gradually decrease once water was supplied to the shear plane. The maximum shear strength decreased by approximately 65-75%, while the residual shear strength decreased by approximately 53-60%. Conclusion: Seismic activity amplifies landslide risk during subsequent rainfall, necessitating proactive mitigation strategies in earthquake-prone areas. This research is anticipated to provide scientific justification and preliminary data for reducing the rainfall threshold for landslide initiation in earthquake-susceptible regions.