• 제목/요약/키워드: permeability tests

검색결과 578건 처리시간 0.022초

단순회귀분석에 의한 토층지반의 투수계수 산정모델 (Estimation model of coefficient of permeability of soil layer using linear regression analysis)

  • 이문세;김경수
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2009년도 춘계 학술발표회
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    • pp.1043-1052
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    • 2009
  • To derive easily the coefficient of permeability from several other soil properties, the estimation model of coefficient of permeability was proposed using linear regression analysis. The coefficient of permeability is one of the major factors to evaluate the soil characteristics. The study area is located in Kangwon-do Pyeongchang-gun Jinbu-Myeon. Soil samples of 45 spots were taken from the study area and various soil tests were carried out in laboratory. After selecting the soil factor influenced by the coefficient of permeability through the correlation analysis, the estimation model of coefficient of permeability was developed using the linear regression analysis between the selected soil factor and the coefficient of permeability from permeability test. Also, the estimation model of coefficient of permeability was compared with the results from permeability test and empirical equation, and the suitability of proposed model was proved. As the result of correlation analysis between various soil factors and the coefficient of permeability using SPSS(statistical package for the social sciences), the largest influence factor of coefficient of permeability were the effective grain size, porosity and dry unit weight. The coefficient of permeability calculated from the proposed model was similar to that resulted from permeability test. Therefore, the proposed model can be used in case of estimating the coefficient of permeability at the same soil condition like study area.

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Permeability imaging in granitic rocks based on surface resistivity profiling

  • Sudo Hiroshi;Tanaka Toshikazu;Kobayashi Tsuyoshi;Kondo Tatsutoshi;Takahashi Toru;Miyamoto Masaharu;Amagai Mitsuru
    • 지구물리와물리탐사
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    • 제7권1호
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    • pp.56-61
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    • 2004
  • In order to image the distribution of permeability in granitic rocks, we carried out two-dimensional (2D) resistivity profiling, together with in-situ permeability tests, electrical logging of boreholes, and resistivity measurements of rock core samples in a laboratory. Based on the electrical logging and in-situ permeability data from boreholes, we obtained empirical equations which relate resistivity and permeability of the granitic rocks in the area studied. We then applied the empirical equation to a 2D resistivity section, to produce a 2D permeability section of the granitic rocks. In this paper, we present details of the field data and of the procedure for conversion from the resistivity section to a permeability section. The observed relationship between resistivity and permeability of the rocks is also discussed.

개량형 수평배수 압밀시험 장치에 의한 압밀특성 평가 (Assessment of Consolidation Properties Using Modified Oedometer for Radial Drainage Condition)

  • 전제성
    • 한국지반환경공학회 논문집
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    • 제10권7호
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    • pp.143-150
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    • 2009
  • 연약지반의 적정 압밀속도 및 압밀침하량 예측에 있어 유효응력, 투수계수, 압밀계수, 체적변화계수 등의 물질함수는 가장 중요한 요소로 작용한다. 본 연구에서는 수평배수 조건에서의 압밀 물질함수 산정을 위한 개량형 수평배수 압밀시험 장치를 고안하고, 이를 이용하여 고함수비 해성점토에 대한 압밀시험을 실시하였다. 시험에 이용된 시료는 상부 준설매립 지반과 하부 원지반점토로 구성된 남해안 산업단지 조성 현장에서 채취하였다. 기존의 표준압밀시험을 동시에 실시하였으며, 이 결과를 이용하여 배수조건별 간극비, 유효응력, 투수계수, 압밀계수, 체적변화계수 등을 분석하였다. 압밀 물질함수는 Stark(2005)이 제안한 소성지수 포함의 회귀분석 방정식 형태로 표현되었으며, 이를 통해 투수성에 대한 이방성 특성을 산정할 수 있었다.

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투수계수에 미치는 초음파의 영향 (Effect of Ultrasound on Permeability)

  • 목진만;김영욱;김지형
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2003년도 봄 학술발표회 논문집
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    • pp.613-620
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    • 2003
  • This study investigated the effect of ultrasound on the permeability of the granular soil. The investigation laboratory experiments, and laboratory tests were conducted under a broad range of conditions including energy levels of ultrasonic waves, time for the treatment, and type of the soil. The results of the study show that sonication enhances the permeability of the soil specimens significantly. The degree of varies with sonication power and duration of application, and type of soil.

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세립분의 함유량이 Sand Column의 투수성에 미치는 영향 (The Effects of Fines on the Permeability in Sand Column)

  • 이진수;장용채
    • 한국항해항만학회지
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    • 제29권3호
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    • pp.263-268
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    • 2005
  • 세립분의 함유량, 구속압력과 건조밀도에 따른 Sand Column의 투수성에 대한 시험을 실시하였다. 삼축투수시험은 세립분의 함유량 (5, 15, 25, $35{\%}$), 구속압력($\sigma_3^'=0.5,\;1.0,\;2.0,\;3.0{\cal}kg/{\cal}cm^2$)과 건조밀도($\gamma_d=1.50,\;1.55,\;1.60,\;1.65 {\cal}g/{\cal}cm^3$)를 달리한 여러 종류의 시료에 대하여 수행되었다. 삼축투수시험 결과 세립분 함유량, 구속압력 및 건조밀도가 커질수록 투수계수는 작아지는 것을 알 수 있었다. 특히, 세립분의 함유량에서는 $0.01{\cal}mm$ 입경 이하의 세립분이 증가할수록 투수성이 매우 크게 감소하고, 구속압력과 건조밀도에서는 낮은 구속압력수준 ($\sigma_3^'=0.5{\~}1.0{\cal}kg/{\cal}cm^2$)과 낮은 수준의 밀도($\gamma_d=1.50{\~}1.55{\cal}g/{\cal}cm^3$) 변화에서 투수성의 감소가 매우 크게 일어남을 알 수 있었다.

Permeability Characteristics of Sand- Bentonite Mixtures

  • Chang, Pyoung-Wuck;Chae, Yong-Suk
    • 한국농공학회지
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    • 제39권2호
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    • pp.26-31
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    • 1997
  • Abstract A series of permeability tests was performed on the mixtures with specific mixing rates of sand and bentonite using modified rigid-wall permeameter. Sand-bentonite mixtures were permeated by organics, ethanol and TCE. Permeability of bentonite with several mixing rates had a tendency to decrease up to initial one pore volume and permeability was thereafter converged to a constant value. When sand-bentonite mixtures was permeated by water, permeability was decreased at the beginning but it was thereafter converged to a constant. Among several mixing rates, permeability was greatly decreased at 15% of mixing rate. When sand-bentonite mixtures with 15% mixing rate was permeated by ethanol, permeability was about 10 times larger value than permeability of water. Peameability was shown greater values when permeated by TCE (TrichloroEthylene) followed by ethanol. Suitable mixing rate of sand-bentonite for a liner of waste landfills was detected.

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Significance of nonlinear permeability in the coupled-numerical analysis of tunnelling

  • Kim, Kang-Hyun;Kim, Ho-Jong;Jeong, Jae-Ho;Shin, Jong-Ho
    • Geomechanics and Engineering
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    • 제21권2호
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    • pp.103-109
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    • 2020
  • The inflow rate is of interest in the design of underground structures such as tunnels and buried pipes below the groundwater table. Soil permeability governing the inflow rate significantly affects the hydro-geological behavior of soils but is difficult to estimate due to its wide range of distribution, nonlinearity and anisotropy. Volume changes induced by stress can cause nonlinear stress-strain behavior, resulting in corresponding permeability changes. In this paper, the nonlinearity and anisotropy of permeability are investigated by conducting Rowe cell tests, and a nonlinear permeability model considering anisotropy was proposed. Model modification and parameter evaluation for field application were also addressed. Significance of nonlinear permeability was illustrated by carrying out numerical analysis of a tunnel. It is highlighted that the effect of nonlinear permeability is significant in soils of which volume change is considerable, and particularly appears in the short-term flow behavior.

실내실험에 의한 부산점토의 투수특성 (Permeability Characteristics of Pusan Clay from Laboratory Tests)

  • 정성교;장우영;;김성렬
    • 한국지반공학회논문집
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    • 제22권11호
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    • pp.133-142
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    • 2006
  • 낙동강 하구지역에는 세계적으로 드물게 연약한 부산점토가 두껍게 분포하고 있다. 최근의 지반개량공사에서 압밀침하에 대한 과소평가 문제가 발생하여 이 점토의 투수특성에 대한 연구가 절실히 요구되고 있다. 따라서 본 연구에서는 그 점토의 투수특성을 규명하기 위한 목적으로 낙동강 하구의 두 지역을 연구대상현장으로 선정하여 불교란 시료채취를 실시하고 이 시료에 대하여 자연점토는 물론 연직 및 수평배수 압밀실험 중에 실내 변수두 투수실험에 의하여 연직 및 수평 투수계수를 측정하였다. 이 결과로부터 자연상태 및 압밀상태 하에서의 투수계수, 투수 이방성 및 그들의 상관관계 규명은 물론 해외의 다른 점토들에 대한 투수특성과의 비교를 수행하였다.

해양폐기물을 이용한 수밀콘크리트 개발에 관한 연구 (An Experimental Study on the Low Permeability Concrete with the Marine Wastes)

  • 백신원;김인배
    • 한국산업안전학회:학술대회논문집
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    • 한국안전학회 2003년도 춘계 학술논문발표회 논문집
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    • pp.74-79
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    • 2003
  • Many marine wastes such as seaweeds are casted aside at the seasides. So, the objective of this study is to apply the marine wastes to the concrete. To this end, mortar and concrete tests with the marine wastes have been conducted. The results of the present mortar and concrete tests indicate that the mortar and concrete with marine wastes admixtures exhibits very low permeability. The present study provides a firm base for the use of very low permeable concrete and the application of the marine structures and the submerged structures.

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재생 콘크리트의 내구성에 관한 실험적 연구 (An Experimental Study on the Recycled! Concrete Durability)

  • 이명규;정상화;김인수
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2003년도 봄 학술발표회 논문집
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    • pp.675-680
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    • 2003
  • In this study, various tests are performed for the durability of the concrete using domestic recycled coarse aggregate including drying shrinkage, permeability, freezing-thawing resistance and $CO_2$ diffusivity. Tests of freezing-thawing resistance, chloride ion permeability and $CO_2$ diffusivity of recycled concrete show favorable results. But, the maximum drying shrinkage ratio to normal concrete is increased 24% with increasing substitution ratio of recycled aggregate. Therefore, for the use of recycled concrete in structures, the preventive measures of drying shrinkage is necessary in mix design and the adequate substitution ratio of recycled aggregate should be proposed.

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