• 제목/요약/키워드: a kind of soil

검색결과 233건 처리시간 0.023초

흙의 다짐도에 따른 인발저항특성 연구 (Pullout Resistance of Geogrid Reinforced Soil according to Compaction Degree)

  • 주재우;김병욱;박종범
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 1999년도 토목섬유 학술발표회 논문집
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    • pp.11-20
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    • 1999
  • The method which makes the soft ground reinforced by using the geogrid, a kind of geosynthetics has been getting popular and its usefulness also has been increased due to reduction in costs, ease of construction and great exterior view, But the study on the frictional characteristics, which is the important factor in design, between reinforcement and soil is insufficient. In this study, compaction degrees were considered through large-scale pullout tests. As a part of studying on estimation of pullout frictional characteristics between soil and geosynthetics, pullout tests were peformed and from the result of pullout tests, pullout frictional parameters between soil and geosynthetics were obtained and pullout behaviors were learned.

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울산 달천광산 인근의 식물체 중금속 축적에 관한 연구

  • 김철;천미희
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2006년도 총회 및 춘계학술발표회
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    • pp.131-137
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    • 2006
  • This study was investigated the contents of heavy metals in plants at Dalcheun mine area, in order to offer basic data for phytoremedation on soil contamination by heavy metals. As the results of this study, the contents of Ni, As, Cd in plants were the highest at the west area of Dalcheun mine area. But the content of Zn was similar in all of Dalcheun mine area. For the herbaceous plants, the contents of heavy metals were higher in plants which were included in Gramineae and Compositae than any other families. And then the contents of Ni, Zn, Cd in root were higher $1.4{\sim}1.8$ times than stem, especially the content of As was higher 4 times. For the trees, the contents of heavy metals were usually high in Zanthoxylum piperitum, Pine tree, Chestnut tree, Quercus acutissima and Lindera obtusiloba. The contents of heavy metals with parts of tree were almost same range. All experimental result, we paid attention on two conclusions. First, the contents of heavy metals in herbs was higher than in trees. And second, if there were some spices that the content of heavy metal in leave were higher than in root, they could accumulate that kind of heavy metal. Therefore, It is above 2 times which the content of heavy metal in the leave is higher than in the root about herbs, that kind of plants was regarded as a accumulation species. According as the heavy metals, accumulation species were selected. We think that the accumulation species are able to absorb the heavy metals from the soil, they will make use of phytoremedation on contaminated soil by heavy metals.

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FGC계 고화재를 이용한 Soilcrete 배합설계에 관한 연구 (A Study on the mix design for the Soilcrete by Using FGC Soil Stabilizer)

  • 천병식;고갑수;김진춘;하상욱
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 1999년도 가을 학술발표회 논문집
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    • pp.293-300
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    • 1999
  • Soilcrete has been the traditional material for the paving and soft ground improvement techniques. But because the durability is not excellent and the quality is not homogeneous, it has not been used for the various purposes up to date. And because the quality of soilcrete is apt to be changed by the content of water and soil stabilizer, and the kind of soil and soil stabilizer, it is not free of cares. But with the increase of naturally oriented needs for the light traffic road such as pedestrian roads of the garden, golf courses and sidewalks, the cases of soilcrete paving has been increased recently. This study aims at making the reference table of the mix design in accordance with the required design specifications for the soilcrete admixtures by the FGC soil stabilizer by using the statistical experiment method. The treated soil is the clay which are widely spreaded in Korea. As the results of this study we can derive the effective reference mix design table for the clay soil treated by the FGC soil stabilizer in accordance with the compressive strength of 50∼200kg/$\textrm{cm}^2$ soilcrete with respect to the contents of water, soil stabilizer and fine sand.

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Pseudomonas putida Strain 17 Isolated from Replant Soil Promotes Tomato Growth and Inhibits Conidial Germination of Soilborne Plant Pathogens

  • Lee, Sang-Woo;Ahn, Il-Pyung;Lim, Jae-Wook;Lee, Yong-Hwan
    • The Plant Pathology Journal
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    • 제21권3호
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    • pp.244-251
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    • 2005
  • The induction of growth promotion on numerous crops by rhizobacteria is a well documented phenomenon. In case of tomato (Lycopersicon esculentum), fruit yield is higher in replant soil than that in fresh soil. To investigate what kind of rhizobacterium is involved, microbial community in rhizosphere and on rhizoplane of tomato plants from each soil was analyzed by dilution plating on selective media. Many Gram-negative bacteria and actinomycetes were isolated from tomato in replant soil. One Gram-negative rhizobacterium isolated was identified as Pseudomonas putida based on its biochemical characteristics, fatty acid methyl ester analysis and 16S rDNA sequence. This bacterium designated strain 17 inhibited the growth of Pseudomonas corrugata, and increased growth of tomato seedlings. In addition, its culture filtrate inhibited conidial germination of plant-pathogenic fungi such as Fusarium oxysporum f. sp. radicis-lycopersici, F. oxysporum f. sp. cucumerinum, and Nectria radicicola. Scanning electron microscopy revealed strain 17 colonized and persisted on the epidermal surfaces of tomato radicles and roots. These results suggest that P. putida strain 17 may serve as a biological control agent to suppress multiple soil-borne diseases for tomato plants. Increased microbial populations that suppress deleterious microorganisms including pathogens could be one of the major factors in increased tomato yield in replant soil.

Lime addition chemical stabilization of expansive soil at Al-Kawamil city, Sohag region, Egypt

  • Farghaly, Ahmed Abdelraheem;El-Shater, A.;Naiem, Mostafa Abdou Abdel;Hamdy, Fatma
    • Advances in Computational Design
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    • 제5권1호
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    • pp.1-11
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    • 2020
  • Soil is the fundamental element in the construction process. Soil problems affect the safety of the structures, even so the high quality of the structures and so, bad soil found the structures will affect the lifetime or even destroy the structures built on it. Therefore, the study of soil is an important step in the construction process and the investigation of the most effective characteristics of a special kind of soil (shale soil), i.e. Atterberg limits, swelling pressure, swelling potential and unconfined compression strength, are the most effective soil properties. A big projects will be constructed in new urban extension areas with expansive shale soils, like at Al-Kawamil and new Akhmim shale soils which associated with soil problems, treatment system should be used to ensure the stability of the soil under the structures foundations one of the most effective methods is by adding lime solution to the soil by specific quantities, which affect on the properties of the shale soil by decreasing the swelling and increasing the compressive strength of the treatment soils. Experimenting with the soil added to the lime, it was found that the addition of lime solution 6% improve c j the properties of the soil. The results of the tests showed the high effectiveness of using lime in the treatment of Al-Kawamil soil

안정동위원소 조성을 이용한 TCE 오염원 규명방법 소개 (A Review on Identification Methods for TCE Contamination Sources using Stable Isotope Compositions)

  • 박영윤;이진용;나원종;김락현;최필성;전성천
    • 한국지하수토양환경학회지:지하수토양환경
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    • 제18권3호
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    • pp.1-10
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    • 2013
  • This study was performed to summarize application of ${\delta}^{13}C$, ${\delta}^{37}Cl$ and ${\delta}D$ of trichloroethylene (TCE) to studies on environmental forensic field regarding identification of TCE sources and evaluation of contribution of TCE to groundwater using data collected from literatures. ${\delta}^{13}C$, ${\delta}^{37}Cl$ and ${\delta}D$ of TCE give some information regarding sources of TCE because they show specific value according to manufacturing method. Also, TCE do not show a significant isotopic fractionation owing to adsorption and dilution. The isotopic fractionation mainly occurs by biodegradation. In addition, isotopic fractionation factor for TCE is different according to a kind of microorganism participated in biodegradation. However, the isotopic data of TCE have to be applied with chemical compositions of TCE and other hydrogeologic factors because isotopic fractionation of TCE is influenced by various factors.

복합유용미생물 및 수생식물을 활착시킨 흙블록을 이용한 자연정화 처리방법 연구 (Natural Purification Treatment using Soil Brick with Combined Effective Microorganisms and Emergent Plants)

  • 심학재;오용걸;박철휘;강원수
    • 상하수도학회지
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    • 제29권5호
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    • pp.543-550
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    • 2015
  • In this study, using soil brick with combined effective microorganisms and emergent plants was identified which it can increase the effect of conservation and improvement of water. Lab-test was consist of four kind of reactors and each of reactors were A(rawwater), B(soil brick), C(emergent plant) and D(soil brick+emergent plant). Iris pseudoacorus, Phargmites australis, Typha angustifolia and Zizania latifolia were used for emergent plant. Evaluation of application on various environment were performed on agricultural waterway and pond. The pH measurement test of soil brick was performed due to evaluate whether a strong alkaline water flows out of the soil brick. Result of lab-test, removal efficiency of D was better than removal efficiency of A presenting 20.9%, 27.9% 21.5%, 33.8% and 58.4% for $COD_{Cr}$, $BOD_5$, TN, TP and TSS respectively. Removal efficiency of soil brick on agricultural waterway was revealed to be 49.5%, 45.0%, 43.7%, 37.3% and 28.6% for $COD_{Cr}$, $BOD_5$, TN, TP and TSS respectively. And removal efficiency of soil brick on the pond was revealed to be 12.7%, 10.5%, 9.32%, 10.4% and 36.3% for $COD_{Cr}$, $BOD_5$, TN, TP and TSS respectively. Result of pH measurement test of soil brick was neutral which was about 6 to 8.

토양 매설 배관의 음극방식과 환경인자 간의 상관관계 (Relationship between the Cathodic Protection of Pipe Buried in Soil and Environmental Factors)

  • 최승헌;원석연;유영란;김영식
    • Corrosion Science and Technology
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    • 제21권5호
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    • pp.372-380
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    • 2022
  • The external corrosion control of buried pipes can be achieved by a combination of coatings and cathodic protection to maximize effectiveness. One of the factors affecting cathodic protection is the environmental soil conditions. Because soil is a kind of electrolyte, the environmental conditions of soil may be changed by the atmospheric environment. Therefore, in this study, changes in environmental soil factors by atmospheric environmental factors were monitored. In cathodic protection, on-potential and off-potential were measured from December 2021 to July 2022. The effects of external environmental factors and soil environmental factors on cathodic protection were analyzed. Changes in outdoor temperature affected soil temperature, and soil conductivity had a proportional relationship with soil humidity, but outdoor humidity and precipitation did not significantly affect humidity and conductivity of the soil. In contrast, in cathodic protection, the on-potential was affected by temperature, humidity, the conductivity of the soil, and the anode used, but the off-potential was little affected by these factors.

선단확장형 쏘일네일링 공법 개발과 거동특성 분석 (The Development of End-expanded Soil Nailing Method for Ground Reinforcement and its Behavior Characteristics)

  • 문홍득;정연득
    • 한국지반환경공학회 논문집
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    • 제14권3호
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    • pp.19-27
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    • 2013
  • 최근, 갑작스런 집중호우로 인하여 자연 및 인공사면의 붕괴가 종종 발생하고 있다. 이를 예방하기 위한 여러 가지 보강공 법들이 개발되어 적용되고 있다. 그 중에서도 쏘일네일링 공법은 시공성과 경제성 등의 이유로 그 활용이 증대되고 있다. 쏘일네일링 공법은 다른 보강공법들과 함께 사용하는 경우도 있으며, 또한 강재와 시멘트그라우팅과의 일종의 복합 구조체로서 지반과 그라우팅사이의 마찰력을 활용하는 공법이다. 본 연구에서는 선단확장형 쏘일네일링 공법을 개발하였으며, 이는 네일 끝단에 앵커체가 부착되어 있다. 이 앵커체는 네일링 작업 중 네일 끝단에서 확개되면서 지반에 정착되게 된다. 본 연구에서는 네일링 시공 후 그라우팅을 하지 않은 상태와 그라우팅 후 양생이 된 경우 각각에 대해 현장인발저항시험을 실시하였다. 시험결과로부터 선단확장형 쏘일네일의 선단쐐기력을 분석하였으며, 거동특성을 종합적으로 고찰하였다.

식물생장물질의 토양관주와 엽면살포가 뽕나무의 발근에 미치는 영향 (Effect of Pour Into Soil and Spray on Leaves of Plant Growth Substances on the Root Out of Mulberry)

  • 김문협
    • 한국잠사곤충학회지
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    • 제20권1호
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    • pp.1-4
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    • 1978
  • The root-out of mulberry saplings has been studied by pour into soil and spray on leaves of the plant growth substances. In addition, the effect of "Rutin", a kind of plant growth hormones has been also studied on promoting the rootability of mulberry scions by dipping the scions at the various concentrations. The results are summarized as follows: (1) It is likely to be effective on acceleration of the rootability resulting in increase of rooting ratio by pour into soil at the concentration of 1 ppm and 10 ppm NAA, 10 ppm and 100 ppm Rutin, and 5000 fold solution of Atonic, respectively (2) Growth of branch is only promoted by leaf spray of 0.5% urea, 0.005% and 0.01% Rutin, and 5000 fold solution of Atonic without increasing the root weight. (3) It seems that 0.05% of Rutin is of practical use, and 0.05% to 0.4% of "Rutin" accelerates the root-out of mulberry scions as well as NAA does.

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