• 한국조경학회지
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• 제30권1호
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• pp.96-104
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• 2002

This study was conducted to investigate physical properties of soil and turfgrass wear characteristics within turfgrasses inside or outside the stadium A 1/1000 scale model Inchon world cup soccer d[me was constructed for this test. Turfgrasses planted inside and outside the model dome were; Kentucky bluegrass(KB), Kentucky bluegrass + perennial ryegrass mixture (KB+PR), Kentucky bluegrass + tall fescue + perennial ryegrass mixture (KB+TF+PR), Zoysia japonica 'Anyangjungzii'(ZA) and Zoysia japonica 'Zenith\`(ZZ). The rootzone was constructed by the multi-layer method (United States Golf Association method). Traffic on turfgrasses was treated with a 120kg roller. Surface soil hardness, soil penetration and water infiltration values on cool-season grasses(KB, KB+PR, KB+TF+PR) was found to be better for soccer play compared to zoysiagrasses(ZA, ZZ). No big differences in surface soil hardness, soil penetration and water infiltration values were found between inside and outside of the model dome. Wear damage on cool-season grasses caused by the traffic treatment was low compared to zoysiagrasses. However, there was no difference in wear damage by the traffic treatment within cool-season grasses while wear damage on ZA was higher than on ZZ within zoysiagrasses. It could be concluded that physical properties and wear characteristics on cool-season grasses were much better for soccer play than on zoysiagrasses.

• 한국지반환경공학회 논문집
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• 제7권6호
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• pp.45-56
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• 2006

최근 인구증가에 따라 쓰레기 매립장의 수요가 점점 늘어가는 실정이나 쓰레기 매립장의 건설은 점토의 부족과 차수층의 고비용으로 인하여 많은 문제점이 있다. 이에 본 논문에서는 투수계수뿐만 아니라 전단강도도 확보되는 저렴한 차수재 개발을 위하여 우리나라에 널리 분포하고 있는 화강풍화토와 투수저감효과가 뛰어난 벤토나이트를 적절히 혼합하여 고가의 벤토나이트가 가장 적게 소요되는 최적의 중량비(B/S)를 산정하기 위하여 일련의 다짐시험과 삼축압축시험기를 이용한 압밀, 투수 및 전단시험을 실시하였다. 차수재의 기준인 $k=1{\times}10^{-7}cm/sec$ 이하를 만족시키기 위하여 모재인 화강풍화토를 네 가지의 입경으로 조절하여 시료성형을 하였으며 각 입경에 따라 B/S를 5%씩 증가시키면서 시험을 실시한 결과, No. 100체에 통과된 화강풍화토의 B/S=15%인 경우에서 차수재 기준을 만족하였다. 그리고, 투수시험결과 산정된 투수계수의 실측치와 Chapuis가 제안한 두 가지 투수계수 예측식을 비교분석하였으며, 본 논문에 사용된 화강풍화토-벤토나이트 혼합토에 적합한 투수계수 예측식을 제시하였다. 본 연구에 사용된 혼합토의 최적 중량비는 투수측면과 강도측면 모두에서 15%로 나타났다.

• 한국지반환경공학회 논문집
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• 제3권4호
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• pp.29-35
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• 2002

본 연구는 유기질토를 토공재로서 활용할 목적으로 시료A(모래+유기질토)와 시료B(풍화토+유기질토)의 두 가지 시료를 유기질토 혼합비를 5%, 10%, 20%, 30%, 40%, 50%로 혼합하여 각종 실내시험을 실시하였다. 시료A, B의 용출시험에 의한 COD값은 순수 유기질토에 비해 상당히 낮은 값을 보였으며, 초기 침출수의 COD 값은 침출수 수질기준을 약간 상회하였지만 용출시작 4시간후의 COD 값은 매우 적게 나타났다. 모래와 유기질토의 혼합토는 유기질토 혼합비 40%(유기물함유량 11.3%)내에서는 성토재로서의 활용이 가능한 것으로 나타났으며, 풍화토와 유기질토의 혼합토는 유기질토 혼합비 30%(유기물함유량 16.4%)이내에서 토공재로서 활용이 가능하다고 판단되어진다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제16권5호
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• pp.90-96
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• 2011

Simultaneous removal of heavy metals (Cd, Pb) and diesel-fuel from a soil column was evaluated by respectively flushing with sodium dodecyl sulfate (SDS) solution, mixture of SDS and sodium iodide (SDS + NaI), and surfactant foam (SDS + NaI foam). First, this study evaluated these flushing methods to the heavy metals only-contaminated soil for removal of heavy metals from the heavy-metal only contaminated soil column. After 7 pore volume flushing of the soil column, Cd removal efficiencies from the soil were 40% by SDS solution, 50% by SDS + NaI mixture, and 60% by surfactant foam. The flushing results implied that anionic surfactant and ligand can be efficiently applied to extraction of Cd from the heavy metal contaminated soil. Furthermore, surfactant foam flushing showed an increased flushing efficiency with enhancing the contact between surfactant solution and soil. However, Pb removal efficiency by these flushing methods did not show any difference unlike those of Cd. Second, this study eventually evaluated flushing methods for simultaneous removal of heavy metals and diesel-fuel from the soil column with 7 pore volume flushing. Diesel-fuel removal efficiencies were 50% by SDS + NaI flushing and 90% by SDS + NaI foam flushing. Cd removal efficiency by the foam flushing reached to 80% which was higher than the result of the previous heavy metals onlycontaminated soil experiment. This result implied that diesel-fuel could act as a metal-solvent while it contacted to heavy metals present in the soil. This study clearly showed that surfactant foam flushing simultaneously removed heavy metals and diesel fuel from the soil column.

• 한국농공학회논문집
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• 제57권1호
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• pp.99-109
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• 2015

In the construction industry, the interest for recycling aggregates is rising as more people demand for alternatives due to lack of supply of natural aggregates and environmental problems. However, in order for recycled aggregates to be used in infrastructures, stability and other factors need to be verified. Therefore, the objective of this study is to analyze the sensitivity of soil properties to secure slope safety according to various heights of embankment when bottom ash and dredged soil mixture is applied in the embankment. In most cases, all heights were safe for the slide for the embankment whether the water level is full or sudden draw down. The result of the sensitivity analysis revealed that the unit weight of embankments is highest among all factors to be considered. However, the sensitivity of the unit weight became smaller and the sensitivity of the friction angle of embankments increased with the height of embankments. The sensitivity of factors of core materials is very small because the core has weaker physical properties than those of the embankment. The effect of the height for each factor is different for each slope and water levels. The sensitivity of the unit weight of embankments is most affected when the height is 60m in the upstream slope. To conclude, bottom ash and dredged soil mixture can be applied in the embankment and different factors must be considered in different scale because the sensitivity depends highly on the height of embankments.

• 한국토양비료학회지
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• 제48권1호
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• pp.44-49
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• 2015

Urea has been the most useful N-source, due to lower cost per unit of N. But nitrogen use efficiency of urea may be reduced because of losses from agricultural system by volatilization of ammonia to atmosphere. This study was conducted to evaluate the nitrogen efficiency and growth of hot pepper (Capsicum annuum L.) by mixed treatment with nitrogen and zeolite. They were treated with N $161kg\;ha^{-1}$, N $230kg\;ha^{-1}$, nitrogenzeolite mixture (NZM) $161kg\;ha^{-1}$, NZM $230kg\;ha^{-1}$ and N $0kg\;ha^{-1}$, respectively. In the soil chemical properties after experiment, soil pH decreased but available $P_2O_5$, EC and total nitrogen increased in nitrogen-zeolite mixture treatment. $NO_3-N$ content in the soil showed the highest level in NZM $230kg\;ha^{-1}$. NZM $161kg\;ha^{-1}$ treatment increased growth and yield of hot pepper compared to urea alone. Nitrogen utilization efficiency of hot pepper plant was 47.15% at the treatment of NZM $161kg\;ha^{-1}$, while 36.74% at N $230kg\;ha^{-1}$. These results showed that application of mixture of nitrogen and zeolite had positive influence to improve the efficiency of nitrogen utilization and increase of red pepper yield.

• 한국환경복원기술학회지
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• 제8권2호
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• pp.90-97
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• 2005

This study aimed to address problems and suggest solutions in applying seed mixture design criterior of slope revegetation works according to the "Slope revegetation design and guidelines(proposed)" proposed by the Ministry of Construction and Transportation. To do this, a proper thickness of attaching soil media was identified in April experiment where the thickness and slopes varied. The results were as follows. In the test, the coverage rate of plot where exotic grass was not sowed increased with time and was 79.3% after three months of seeding, which indicated less risk of soil erosion. When applying the provisional standards of the plant mix proposed by the Ministry of Construction and Transportation, tree seeds and native plants were found ill in the early stage in all test lands due to exotic grass. This was because exotic grass which grew well in the early stage, could grow densely, so it might hamper the growth of other plants. When slope revegetation were planted and goals were set for herb, shrub and tree dominant mixture types, it was required to shift focus toward nursing up native plants first rather than early plantation of exotic grass.

• 한국지반공학회논문집
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• 제15권5호
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• pp.291-300
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• 1999

BTEX로 오염된 혼합토(사질토/점토)의 정화를 위한 계면활성제 기법의 적용성 및 제거효율에 대한 연구를 진행하였다. 초기농도 275mg/kg으로부터 1975mg/kg의 BTEX로 오염시킨 8개의 컬럼에 물, methyl alcohol과 계면활성제 용액을 주입하였고 이때 계면활성제와 첨가물의 혼합과 비혼합시에 대해 제거거동을 비교 분석하였다. 물을 이용한 흙 세척법의 적용 결과 850 간극부피의 물을 주입하여 98%의 제거 효율을 보였으나 8mg/kg 이하의 저농도에서는 더 이상 제거가 이루어지지 않고 일정한 양상을 가지는 tailing effect를 보였다. 본 실험 결과 가장 우수한 조건은3% ethyl alcohol과 3% SXS를 첨가한 4% SOFTANOL(equation omitted)-90을 간헐적으로 주입한 경우였으며 이 때 95 간극부피에서 99.5%의 제거효율을 보였다. 실험결과 물을 주입하였을 경우 850 간극부피를 주입한 반면, 계면활성제 적용시 95-165 간극부피에서 84.5%-99.5%의 제거효율을 보였는데 이는 계면활성제 기법을 오염된 지반 정화에 효율적으로 적용할 수 있음을 나타내는 것이다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제14권2호
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• pp.17-25
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• 2009

토양 세척/세정(soil washing/flushing)기법을 적용하여 카드뮴과 구리로 오염된 토양을 처리하기 위해 최적의 유기산 및 무기산 용출제 선정 실험을 batch 및 column test를 통하여 수행하였다. 널리 알려진 EDTA와 비교한 Citric acid는 저분자 유기산 용출제로 구리와 카드뮴의 제거효율이 EDTA를 제외한 다른 유기산 용출제에 비해 처리효율이 높았으며, 탄산은 독성이 가장 낮으면서 토양공극효과를 동시에 수반할 수 있는 무기산 용출제로 확인되었다. 최적의 유/무기산 혼합용출제는 citric acid와 탄산의 혼합 용출제였으며, 최적 농도비는 citric aicd:탄산 = 10:1이었다. 이때의 카드뮴과 구리의 제거효율은 각각 46%와 39%이였다. 탄산은 공극 막힘 현상을 완화시키는 역할으 하는 것으로 확인되었으며, 이는 EDTA + 탄산과 citric acid+탄산에서 용출제의 유량이 점차 증가하는 것을 확인하였따. 따라서, 유/무기산 혼합 용출제는 카드뮴 및 구리로 오염된 토양 처리를 위한 세정 복원기법의 실제현상 적용 시 발생하는 토양공극 막힘 연상을 개선시켜 줄 수 있다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제18권7호
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• pp.63-72
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• 2013

This study estimated stabilization efficiency of As and heavy metal contaminated agricultural soil in abandoned mine through pot experiment. Also contaminants uptake of plant (lettuce) was compared as function of amendment (limestone, steelmaking slag and the mixture of these) addition. In soil solution analysis, concentration of contaminants in soil solutions which added limestone or steelmaking slag were lower than that of the mixture. Especially in As analysis, concentration with 5% (wt) addition of steelmaking slag showed the lowest value among those with other amendments. This seems that As stabilization happens through Fe adsorption during precipitation of Fe by pH increasing. Leachability of As in stabilized soil by TCLP was represented similar result with soil solution analysis. However leachability of heavy metals in stabilized soil was similar with that of non-stabilized soil due to dissolution of alkali precipitant by weak acid. Contaminants uptake rate by plant was also lower when limestone or steelmaking slag was used. However this study revealed that concentration of contaminants in soil solution didn't affect to the uptake rate of plant directly. Because lower $R^2$ (coefficient of determination) was represented in linear regression analysis between soil solution and plant.