• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2005년도 춘계 학술발표회 논문집
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• pp.725-730
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• 2005

In case of the national roads which is opened in the past, there are carried out the expansion and improvement for enlargement of the traffic demand by industrial development and safety road operation to narrow of road width and serious change of the road alignment with effect of topography and graphical features of a mountain. A protection method using vegetation in the cut-slope has been constructed for harmony of ambient environment after cutting the slope recently. But it requires a study because the surface lose and the failure have been occurred in the large cut-slope which is covered by vegetation. In this study it was presented a countermeasure and examined a stability of contained uncertainty in the cut-slope according to the failure example of the cut-slope which is covered by vegetation. The additional research will be necessary against the development of the investigation technique which executes the stability investigation of the cut-slope which is covered by vegetation.

• Structural Engineering and Mechanics
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• 제89권3호
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• pp.253-263
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• 2024

Slope stability is generally paid more attention to in slope protection works, especially for slope containing weak layers. Two indexes of safety factor and failure model are selected to perform slope stability. Moreover, the finite element limit analysis method comprehensively combines the advantage of the limit analysis method and the finite element method obtaining the upper and lower bounds of the safety factor and the failure mode under the slope stability limit state. In this study, taking a waste dump containing a weak layer as an engineering background, the finite element limit analysis method is adopted to explore the potential failure mode. Meanwhile, the sensitivity analysis of slope stability is performed on geometrical and geotechnical parameters of the waste dump. The results show that the failure mode of the waste dump slope is two wedges if the weak layer is located on the ground surface (Model A), while the slope can be observed as three wedges failure if the weak layer is below the ground surface (Model B). In addition, both failure modes are highly sensitive to the friction angle of the weak layer and the shear strength of waste disposal, and moderately sensitive to the heap height, the dip angle and cohesion of the weak layer, while the toe cutting has limited effect on the slope stability. Moreover, the sensitivity to the excavation of the ground depends on the location of the weak layer and failure mode.

• Environmental Analysis Health and Toxicology
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• 제28권
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• pp.13.1-13.5
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• 2013

Objectives: Potential environmental risks caused by chemicals that could be released from a recycled plastic product were assessed using a screening risk assessment procedure for chemicals in recycled products. Methods: Plastic slope protection blocks manufactured from recycled plastics were chosen as model recycled products. Ecological risks caused by four model chemicals - di-(2-ethylhexyl) phthalate (DEHP), diisononyl phthalate (DINP), cadmium (Cd), and lead (Pb)-were assessed. Two exposure models were built for soil below the block and a hypothetic stream receiving runoff water. Based on the predicted no-effect concentrations for the selected chemicals and exposure scenarios, the allowable leaching rates from and the allowable contents in the recycled plastic blocks were also derived. Results: Environmental risks posed by slope protection blocks were much higher in the soil compartment than in the hypothetic stream. The allowable concentrations in leachate were $1.0{\times}10^{-4}$, $1.2{\times}10^{-5}$, $9.5{\times}10^{-3}$, and $5.3{\times}10^{-3}mg/L$ for DEHP, DINP, Cd, and Pb, respectively. The allowable contents in the recycled products were $5.2{\times}10^{-3}$, $6.0{\times}10^{-4}$, $5.0{\times}10^{-1}$, and $2.7{\times}10^{-1}mg/kg$ for DEHP, DINP, Cd, and Pb, respectively. Conclusions: A systematic ecological risk assessment approach for slope protection blocks would be useful for regulatory decisions for setting the allowable emission rates of chemical contaminants, although the method needs refinement.

• 터널과지하공간
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• 제19권6호
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• pp.526-533
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• 2009

본 연구는 광산지역 암반사면이나 광물찌꺼기 적치 사면 등을 보호하기 위한 섬유 방틀공법에 관한 것이다. 섬유 방틀공법은 식생이 자라기 어려운 열악한 환경에서 섬유를 이용해 식생기반을 조성하여 식생이 활착할 수 있도록 도와주는 사면보호공법이다. 섬유 방틀공은 폴리에스테르 섬유매트, 토양, 종자, 사면에 부착을 위한 앵커부로 구성되어 있다. 섬유 방틀공의 무공상태에서 나타난 저조한 발아율을 V형 타공으로 개선하였으며 18개 초본류에 대한 실내발아시험 결과를 토대로 섬유 내 충전재의 최적 배합비를 산정하였다. 최적 배합비는 4곳의 현장 시험시공에 적용 되었으며 활착율이 낮은 현장에서는 보완된 현장시험 시공을 통해 시공된 섬유를 피복하는 식생 활착률이 70% 이상임을 확인하였다. 특히 시험시공 결과 토양보습제는 식생 활착을 위한 충전재 중 가장 중요한 요소로 작용하였다.

• Geomechanics and Engineering
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• 제32권6호
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• pp.639-652
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• 2023

Stepped earth slopes incorporated with anti-slide piles are widely utilized in landslide disaster preventions. Explicit consideration of the three-dimensional (3D) effect in the slope design warrants producing more realistic solutions. A 3D limit analysis of the stability of pile stabilized stepped slopes is performed in light of the kinematic limit analysis theorem. The influences of seismic excitation and surcharge load are both considered from a kinematic perspective. The upper bound solution to the factor of safety is optimized and compared with published solutions, demonstrating the capability and applicability of the proposed method. Comparative studies are performed with respect to the roles of 3D effect, pile location, pile spacing, seismic and surcharge loads in the safety assessments of stepped slopes. The results demonstrate that the stability of pile reinforced stepped slopes differ with that of single stage slopes dramatically. The optimum pile location lies in the upper portion of the slope around L_x/L = 0.9, but may also lies in the shoulder of the bench. The pile reinforcement reaches 10% universally for a looser pile spacing D_c/d_p = 5.0, and approaches 70% when the pile spacing reaches D_c/d_p = 2.0.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 추계 학술발표회
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• pp.527-532
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• 2010

Soil-cement has been broadly used for eco friendly pavement, slope protection and soft soil improvement since it used for the increase of soil strength with cement. Recently, additional agents are mixed with existing soil-cement so as to improve specific properties or functions such as strength, color and permeability of it. This study aims at figuring out the physical and mechanical properties of a soil-cement mixed with crashed oyster shell and loess. The study is specially focused on the applicability of oyster shell as an alternative material for sands. To have his objective achieved a series of uniaxial compression tests were conducted. As a result, it appears that usage of oyster shell may have effect on strength improvement of mixed soils.

• 한국방재안전학회논문집
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• 제17권2호
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• pp.1-11
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• 2024

국내 저수지의 대부분 흙댐으로 되어있다. 흙댐은 건설비용이 저렴하고, 용이한 시공성을 가지고 있기 때문이다. 그러나 흙댐은 침투나 월류에 매우 취약하기 때문에, 과도한 홍수량이 발생하였을 경우 급격한 붕괴 가능성이 매우 높다. 급격한 붕괴는 급격한 홍수량 증가로 이어져, 하류 하천 또는 민가에 매우 큰 피해를 발생시킬 가능성이 있다. 이에 본 연구에서는 흙댐 사면에 포설한 사석의 흙댐 붕괴 지연효과에 대해 실험연구를 수행하였다. 붕괴시간이 지연되면, 대피시간을 확보하여 인명 피해를 크게 줄일 수 있기 때문에 재난 대응 관점에서 큰 의미가 있다고 판단된다. 수리실험은 직선형 개수로에서 수행하였으며, 보호공 사석의 크기를 2가지로 결정하였다. 기존 선행 실험과는 달리 실험을 부정류로 수행하였으며 이를 통해 댐 내부의 수위 상승 변화 효과를 반영하였다. 대상댐은 도수터널에 설치된 가물막이 댐으로 결정하였다. 실험결과 수행한 실험조건에서 사석보호공이 있는 경우 사면의 붕괴를 방지할 수 있었고, 사석보호공이 없는 경우 사석의 입경 증가에 따라 붕괴 시간 지연 효과가 있는 것으로 나타났다. 이는 첨두 유출량 감소로 댐 하류부의 피해를 감소시키는 효과가 있을 것으로 판단된다. 또한 저수지 붕괴에 대한 비상대처계획(EAP) 수립 시 주요 참고자료로 활용될 수 있을 것이다.

• 한국항해항만학회지
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• 제28권7호
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• pp.619-627
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• 2004

Introduction of wave model, considered the effect of shoaling, refraction, diffraction, partial reflection, bottom friction, breaking at the coastal waters of complex bathymetry, is a very important factor for most coastal engineering design and disaster prevention problems. As waves move from deeper waters to shallow coastal waters, the fundamental wave parameters will change and the wave energy is redistributed along wave crests due to the depth variation, the presence of islands, coastal protection structures, irregularities of the enclosing shore boundaries, and other geological features. Moreover, waves undergo severe change inside the surf zone where wave breaking occurs and in the regions where reflected waves from coastline and structural boundaries interact with the incident waves. Therefore, the application of mild-slope equation model in this field would help for understanding of wave transformation mechanism where many other models could not deal with up to now. The purpose of this study is to form a extended mild-slope equation wave model and make comparison and analysis on variation of harbor responses in the vicinities of Ulsan Harbor and Ulsan New Port, etc. due to construction of New Port in Ulsan Bay. We also considered the increase of water depth at the entrance channel by dredging work up to 15 meters depth in order to see the dredging effect. Among several model analyses, the nonlinear and breaking wave conditions are showed the most applicable results. This type of trial might be a milestone for port development in macro scale, where the induced impact analysis in the existing port due to the development could be easily neglected.

• 한국환경복원기술학회지
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• 제19권6호
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• pp.123-132
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• 2016

The study was to introduce the revegetation measures for the improvement of the landscape in October, 2012 on the slope; two and four years after the introduction, the slope was examined to see the status of the revegetation. The result is as follows. The result from examining the soil on the slope, the soil was Loamy sand; which infers that the soil is in a poor condition for improving the scenery. Examining the characteristics of the vegetation-base materials, the soil acidity was pH 6.4 to 6.7; and the soil hardness was 21 to 24mm (hardness quotient of soil), this can be considered a favourable condition, which has no effect on the growth and development of plants. When it comes to the discovery of the species in the area, Lotus corniculatus var., Silene armeria L., Papaver rhoeas, Trifolium pratense L. developed and grew in spring after two years. And in the summer, Lotus corniculatus var., Dianthus chinensis L., Cosmos bipinnatus, Coreopsis drummondii L., Trifolium pratense were founded. And there were Lotus corniculatus var., Dianthus chinensis L., Aster yomena, Coreopsis tinctoria, Trifolium pratense L. in the autumn. According to the examination conducting after four years, Lotus corniculatus var., Dianthus chinensis L., Silene armeria, Cosmos bipinnatus, Coreopsis drummondii L., Papaver rhoeas, Trifolium pratense L. were founded in the spring, and Lotus corniculatus var., Dianthus chinensis L., Cosmos bipinnatus, Coreopsis drummondii L., Trifolium pratense grew in the summer. Lotus corniculatus var., Dianthus chinensis L., Astragalus sinicus, Aster yomena, Coreopsis tinctoria, Trifolium pratense L. were discovered in the autumn. Among the exotic species founded in the area, were Festuca arundinacea, Lolium perenne, Festuca rubra. When it comes to the protection of vegetation and dominance, Lotus corniculatus var., Metaplexis japonica, Coreopsis drummondii L. are the dominant species among the spring plants; and Lotus corniculatus var., Trifolium repens L., Erigeron annuus (L.) Pers. were the dominant plants in the summer. In the autumn, Lotus corniculatus var., Coreopsis drummondii L., Poa pratensis appear to be the dominant plants. The colonies of Pinus densiflora and Castanea crenata var. were formed around the South Sejong IC. Part of the area is occupied by the colony of Alnus hirsuta Turcz. ex Rupr. In terms of shrub, there were Indigofera pseudo-tinctoria, Robinia pseudoacacia, and Rosa polyantha var. genuina NAKA. As ground cover plants, Sasa borealis, Rubus crataegifolius Bunge were founded.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2004년도 Asia Navigation Conference
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• pp.217-225
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• 2004

Introduction of wave model, considered the effect of shoaling, refraction, diffraction, partial reflection, bottom friction, breaking at the coastal waters of complex bathymetry, is a very important factor for most coastal engineering design and disaster prevention problems. As waves move from deeper waters to shallow coastal waters, the fundamental wave parameters will change and the wave energy is redistributed along wave crests due to the depth variation, the presence of islands, coastal protection structures, irregularities of the enclosing shore boundaries, and other geological features. Moreover, waves undergo severe change inside the surf zone where wave breaking occurs and in the regions where reflected waves from coastline and structural boundaries interact with the incident waves. Therefore, the application of mild-slope equation model in this field would help for understanding of wave transformation mechanism where many other models could not deal with up to now. The purpose of this study is to form a extended mild-slope equation wave model and make comparison and analysis on variation of harbor responses in the vicinities of Ulsan Harbor and Ulsan New Port, etc. due to construction of New Port in Ulsan Bay. This type of trial might be a milestone for port development in macro scale, where the induced impact analysis in the existing port due to the development could be easily neglected.