• 한국지하수토양환경학회지:지하수토양환경
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• 제16권4호
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• pp.53-61
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• 2011

This study examined evaluation on stabilization of major and trace elements in tailings by various surface water-preventing materials. Six columns were filled with tailings of the Sinlim mine, then covered with tailings only, compacted soils, clay, soil-bentonite mixture, pozzolan and bentonite mat. After injection of artificial rain water, the leachate was sampled with times (3, 6, 9 and 12 pore volume) and analysed for major (Ca, Na, Mg, K) and trace elements (As, Cd, Cu, Pb, Zn) by ICP-AES. With exception to pozzolan type, the pH values of leachate from the other types became stabilized from 5.5 to 7.5, and EC (electric conductivity) of leachate from them decreased with times. For the pozzolan type, however, the pH and EC of leachate increased with time due to its alkalinity producing system. Concentrations of most major and trace elements in leachate decreased and stabilized with time. Consequently, soil-bentonite mixed cover shows the best ability of water-preventing and reducing mobility of elements in tailings site.

• 한국도로학회논문집
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• 제9권4호
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• pp.171-184
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• 2007

화학적 첨가제를 이용한 안정처리는 지반의 강도증가 및 변형발생을 제어하기 위한 방법으로 깊은 심도까지 광범위하게 적용되어 지고 있다. 화학적 안정처리의 기본목적은 지반의 강도증가, 압축성 감소, 팽창특성 등을 개선하여 지반의 내구성을 증가시키는 것이며, 최근 들어 환경친화적이며 혼합체의 특성 및 혼합속도를 효율적으로 개선한 다양한 형태의 진보적인 시멘트 혼화재가 개발되고 있다. 본 연구에서는 농어촌도로(농도)의 효율적인 포장공법 개발을 위하여 시멘트혼화재를 활용하는 방안을 연구하였으며, 혼화재 종류 및 배합비에 따른 다짐시험, 일축압축강도시험, 동결융해시험 및 휨강도시험을 실시하였다. 본 연구결과에 따르면, 실트질 원지반토가 점토지반에 비해 강도증가 및 동결융해특성이 우수하며, 액상형 시멘트 혼화재가 분말형태 보다 효과적인 것으로 나타났다. 또한 저배합에서도 고강도의 품질을 발휘하여 농어촌도로 표층 내구성 저하를 개선할 수 있을 것으로 판단된다.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2005년도 총회 및 춘계학술발표회
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• pp.253-259
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• 2005

Mine is quickly decline, Nowadays, many of abandoned and closed mines. AMD is abandoned surface water by accumulated yellowboy and caused environmental pollution by amount of heavy metals. The aim of this study waste lime was mixed with the sediment to produce an aggregate far the purpose of neutralizing the acidity and stabilization the heavy metal in the aggregate structure .to pozzolan effect. The result of Waste lime and sediment mixed(5%, 10%, 20%)ration by curing days(3, 7, 38days), After 28 curing days as 5% mixed waste lime leaching solution concentration of all heavy metals is satisfied with regulation limit. Also, the result of fractionate heavy metals to stabilization as 28 curing days very decrease exchangeable and reducible type, and then increase carbonate type. With the above results, waste lime the most effective for the sediment treatment and useful for the recycling waste resource.

• 한국지하수토양환경학회지:지하수토양환경
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• 제27권4호
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• pp.10-21
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• 2022

In the South Korea, 47% of abandoned mines are suffering from the mining hazards such as the mine drainage (MD), the mine tailings and the waste rocks. Among them the mine drainage which has a low pH and the high concentration of heavy metals can directly contaminate rivers or soil and cause serious damages to human health. The natural/artificial treatment facilities by using neutralizers and coagulants for the mine drainage have been operated in domestic and most of heavy metals in mind drainage are precipitated and removed in the form of metal hydroxide, alumino-silicate or carbonate, generating a large amount of mine drainage treated sludge ('MDS' hereafter) by-product. The MDS has a large surface area and many functional groups, showing high efficiency on the fixation of heavy metals. The purpose of this study is to develop a ingenious heavy metal stabilizer that can effectively stabilize arsenic (As) and heavy metals in soil by recycling the MDS (two types of MDS: the acid mine drainage treated sludge (MMDS) and the coal mine drainage treated sludge (CMDS)). Various analyses, toxicity evaluations, and leaching reduction batch experiments were performed to identify the characteristics of MDS as the stabilizer for soils contaminated with As and heavy metals. As a result of batch experiments, the Pb stabilization efficiency of both of MDSs for soil A was higher than 90% and their Zn stabilization efficiencies were higher than 70%. In the case of soil B and C, which were contaminated with As, their As stabilization efficiencies were higher than 80%. Experimental results suggested that both of MDSs could be successfully applied for the As and heavy metal contaminated soil as the soil stabilizer, because of their low unit price and high stabilization efficiency for As and hevry metals.

• 환경영향평가
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• 제29권5호
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• pp.350-362
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• 2020

본 연구에서는 전정가지 부산물과 one-pot 합성방법을 이용하여 철 나노입자가 담지된 바이오차인 INPBC(Iron Nano-Particles Impregnated BioChar)를 제조하고 비소 오염토양의 안정화제로써의 적용 가능성을 평가하였다. INPBC는 전정가지 부산물과 Fe(III) 용액을 220℃에서 3시간 동안 수열반응하고 이후 N₂ 분위기에서 1시간 동안 소성하여 제조하였으며 FT-IR, XRD, BET, SEM을 이용하여 INPBC의 특성을 분석하였다. INPBC의 안정화 성능평가는 국내 E폐광산과 S폐광산의 인근 농경지에서 채취한 비소로 오염된 토양 Soil-E와 Soil-S를 채취하여 4주 동안의 배양실험을 실시하였다. 배양실험 후 토양중 비소의 안정화 정도를 알아보기 위해 TCLP와 SPLP 용출시험을 실시하였다. TCLP와 SPLP의 용출시험결과, INPBC의 적용 농도의 증가에 따라 토양 중 비소의 용출농도는 감소하여 안정화 효율이 높아지는 것을 확인할 수 있었으며, 특히 Soil-E의 경우 SPLP 용출액 중 비소의 농도는 먹는물 수질기준치 이하의 낮은 값을 나타내었다. 안정화 토양의 연속추출시험에서는 쉽게 용출되는 1단계 및 2단계의 분획비율이 감소되고 그 보다 용출이 어려운 3단계 및 4단계의 분획비율이 증가되는 것을 확인할 수 있었으며, 이러한 결과는 오염토양에 주입한 INPBC의 표면에 존재하는 철 나노입자로 인해 토양에서 용출된 비소가 sorption에 의해 안정화된 것으로 판단된다. 본 연구에서 나타난 INPBC의 비소 오염토양의 안정화 효과는 대규모 비소 오염토양의 위해성 저감을 위한 안정화제로서 높은 적용 가능성을 보여 준다.

• 한국지반신소재학회논문집
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• 제20권1호
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• pp.35-44
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• 2021

본 연구는 제지 플라이애시 지반안정재를 활용하여 개량토 토사 비탈면의 현장 적용을 통한 안정화 방법을 연구하였다. 개량토에 요구되는 목표강도는 500kPa이며 토사 비탈면을 개량후 식생이 발아하기 위한 압축강도는 1,000kPa 이하이다. 이 조건을 만족하기 위해 현장에서 반입된 시료를 가지고 표층개량의 주원료인 지반안정재와 혼합하여 배합설계를 거처 강도시험 및 투수시험 그리고 식생 발아시험 등 다양한 시험을 실시 하였다. 그리고 개량토로 시공된 비탈면에 대한 기존 압축시험 결과를 분석한 후 개량토의 지반정수를 제안하였다. 또한 개량토의 비탈면 현장 적용성을 평가하기 위하여 붕괴된 비탈면에 대하여 현장 시공을 실시하여 개량토의 표층부 보강평가를 실시하였다. 그 결과 보강 전에는 안정성을 확보하지 못했지만 개량토로 보강한 이후 안전율은 강우 지속시간 48시간까지 최소 안전율을 확보하는 것으로 나타났다. 그리고 현장 개량토의 압축강도는 설계치인 점착력 200kPa 이상을 확보하고 토양경도계 시험 결과도 규정 값인 18~23mm 이내로 확인되어 개량토 비탈면의 경우 강우에 저항성이 증대되고 표층부의 식물생육이 가능한 것으로 나타났다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2000년도 사면안정 학술발표회
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• pp.3-38
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• 2000

Slope draperies in soil and rock are a well known method to avoid rockfalls into the roads or onto housings. Common wire mesh or a combination of wire mesh and wire rope nets are pinned to the slope by the means of fully grouted nails or anchors. Most of these installations have not been designed to stabilize the slope, but simply avoid the rocks from bouncing. The combination of soil- or rocknailing with a designable flexible facing system offers the advantage of a longterm stabilization of slopes and can replace other standard methods for slope stabilization. The capability to transfer axial and shear loads from the flexible facing system to the anchor points is most decisive for the design of the stabilization system. But the transfer of forces by mesh as pure surface protection devices is limited on account of their tensile strength and above all also by the possible force transmission to the anchoring points. Strong wire rope nets increase the performance for slope stabilizations with greater distances between nails and anchors and are widely used in Europe. However, they are comparatively expensive in relation to the protected surface. Today, special processes enable the production of diagonally structured mesh from high-tensile steel wire. These mesh provide tensile strengths comparable to wire rope nets. The interaction of mesh and fastening to nail / anchor has been investigated in comprehensive laboratory tests. This also in an effort to find a suitable fastening plates which allows an optimal utilization of the strength of the mesh in tangential (slope-parallel) as well as in vertical direction (perpendicular to the slope). The trials also confirmed that these new mesh, in combination with suitable plates, enable substantial pretensioning of the system. Such pretensioning increases the efficiency of the protection system. This restricts deformations in the surface section of critical slopes which might otherwise cause slides and movements as a result of dilatation. Suitable dimensioning models permit to correctly dimension such systems. The new mesh with the adapted fastening elements have already been installed in first pilot projects in Switzerland and Germany and provide useful information on handling and effects.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2009년도 세계 도시지반공학 심포지엄
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• pp.412-419
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• 2009

Large quantity of extra soils discharged from excavation site in Songdo area can be treated by hardening agents and utilized in surface stabilized layer overlying thick reclaimed soft soil deposit. Though surface layer stabilization method using cement or lime for very soft soils has been studied in recent years, but studies on moderately soft clayey silt has not been tried. The purpose of this research is to investigate optimum mixing condition for stabilizing Songdo marine soil with low plasiticity. The optimum mixing conditions of hardening agents with Songdo soil such as kind of agents, mixing ratio, initial water content and curing time are investigated by uniaxial compression test and laboratory vane test. The results indicate that strength increases with high mixing ratio and long curing time, while decreases drastically under certain water content before mixing. Finally, optimum mixing condition considering economic efficiency and workability with test results was proposed.

• 한국지반신소재학회논문집
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• 제4권3호
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• pp.45-52
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• 2005

대부분의 항만구조물은 초연약 지반상에 축조되고 있으며 도로나 건물부지에는 지반개량이 필요하다. 이 논문에서는 여러 사례연구를 통하여 표층처리후의 복토사례에 대하여 몇가지 고려사항을 언급하였다. 또한, 모래나 산토를 이용한 복토공법에 대하여 강도적용이 고려되었다. 국내 복토공법 토목섬유 인장강도는 15t/m, 복토두께는 1.6~3.1m, 점토지반의 표층강도는 $0.2{\sim}1.2t/m^2$이 대표적이다. 표층처리공 시공시 발생되는 지반교란, 점토유출, 장비전도 등의 사고를 최소화하기 위한 연구가 필요하다.

• 한국농공학회논문집
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• 제64권2호
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• pp.37-45
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• 2022

In-situ pilot experiment was carried out to establish a countermeasure on the soil loss from the hill side uplands that was rehabilitated by soil remediation method nearby abandoned mine sites for 2 years. It was considered that the affect of an inclination of cover surface, a stabilization treatment of cover layer by lime and steel refining slag (SRS) and a vegetation of soil surface as an effect factors in the experiment. It was constructed 4 lysimeters (plots, 22 m long, 4 m width) on the hilly side (37% inclination). One plot was control and two plots was treated by 1% lime and SRS. A remind one plot was modified a inclination to 27% to compare the affect of inclination on the amount of cover soil loss. It was attached a reservior tank and water level gauge in the end of lysimeters to measure the amount of the surface water flow and soil loss. It was also installed the automated sensors that could be collect the precipitation, soil moisture content, tension of cover layer in each plots. It was observed that the event of precipitation were caused the soil loss and it were related the physical and chemical properties of cover soil and inclination of surface layer of plots. During the experiment, it was exceeded the national regulation (50 t/ha/yr) in 37% inclination plots even though it was vegetated on the cover soil surface. However, in 27% inclination plot, it was shown that the amount of soil loss was maintained below the national regulation and, more ever, vegetation could reduce the the amount of soil loss. Therefore it was expected that such results could be applied to the future design of rehabilitation projects on the polluted farmland nearby abandoned mine sites.