• Title, Summary, Keyword: soil sample

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A Study on Disturbance Effect of Clay by Block Sampling (대형자연시료 채취를 통한 시료 교란도 분석에 관한 연구)

  • 신윤섭;김연정;김학중;김영웅
    • Proceedings of the Korean Geotechical Society Conference
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    • pp.325-332
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    • 2003
  • In general, soil characteristics are estimated through the sample gathered by field boring without considering sample disturbance. However, soil characteristics must be changed by the degree of sample disturbance. Therefore it be need to estimate the soil characteristic considering sample disturbance which can be occurred by the change of stress condition, sampling technique and handling method. On this study, we analyzed the sample disturbance by using the methods of volume change, residual effective stress, elastic modulus and the curve of consolidation tests. In order to estimate the relationship between sample disturbance and soil characteristics, we used the piston sample and the block sample. As the results, it should be considered in design that the disturbance of the block sample, which affects the strength and compression properties of clay, is smaller than the disturbance of piston sample.

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Concentration Characteristics of PCBs in Pine Needle and Soil at Rural Area (교외지역에서 소나무 잎과 토양 중 PCBs의 농도 특성)

  • Shin Eun-Sang;Yeo Hyun-Gu
    • Journal of environmental and Sanitary engineering
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    • v.21 no.1
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    • pp.1-11
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    • 2006
  • This study was to investigate concentration characteristics of atmospheric PCBs in soil sample and pine needle at rural area. Profiles of PCB congener detected in pine needle and soil sample have a difference that low molecular PCBs mainly existed in pine needle, whereas high molecular PCBs were mainly existed in soil sample because of their different vapor pressure and octanol-air partitioning coefficient($K_{OA}$) of each congeners. Correlation coefficients(r) of PCB congeners simultaneously detected in soil and pine needle were significant (r>0.71, p<0.01), which showed that PCB congeners patterns of atmosphere could be estimated in using pine needle and soil sample indirectly. The contributions(%) of higher molecular PCBs(>penta-CB) to total PCBs in soil sample were higher than those of pine needle and the contribution of lower molecular PCBs(

Quantification of Uncertainty Associated with Soil Sampling and Its Reduction Approaches (토양오염도 평가시 시료채취 불확실성 정량화 및 저감방안)

  • Kim, Geonha
    • Journal of Soil and Groundwater Environment
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    • v.18 no.1
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    • pp.94-101
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    • 2013
  • It is well known that uncertainty associated with soil sampling is bigger than that with analysis. In this research, uncertainties for soil sampling when assessing TPH and BTEX concentration in soils were quantified based on actual field data. It is almost impossible to assess exact contamination of the site regardless how carefully devised for sampling. Uncertainties associated with sample reduction for further chemical analysis were quantified approximately 10 times larger than those associated with core sampling on site. Bigger uncertainties occur when contamination level is low, sample quantity is small, and soil particle is coarse. To minimize the uncertainties on field, homogenization of soil sample is necessary and its procedures are proposed in this research as well.

Significant Parameters for Assessing Soil Contaminant-Leaching to Groundwater and Determining Soil Sample Size in Field Survey

  • Jeong, Seung-Woo;An, Youn-Joo
    • Environmental Engineering Research
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    • v.13 no.2
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    • pp.73-78
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    • 2008
  • For a given soil-contaminated site, a level of soil contamination is characterized and decisions on risk may be made from the risk assessment. The study evaluated critical design factors for the determination of sample size in the sampling design plan and the assessment of soil contaminant- leaching to groundwater. Two variables, the minimum relative detectable difference (T) and coefficient of variation (CV) were evaluated for the sample size determination. The minimum number of samples can be appropriately determined by CV under a T value greater than or equal to 0.2. Soil-contaminant leaching to groundwater was evaluated by using the Soil Screening Level equation of U.S. Environmental Protection Agency and the Risk Based Screening Level equation of American Society for Testing and Materials, with the same input parameters. The groundwater concentrations estimated from soil contaminant concentrations were significantly affected by the Darcy velocity of groundwater and the organic content of soil.

Evaluation of Dynamic Properties of Subballast Materials Used in Korea Using Midsize Resonant Column Test Apparatus (중형 공진주 시험기를 이용한 보조도상 재료의 동적특성 정량화)

  • Lim, Yu-Jin;Sin, Joong-Hoon;Park, Kyung-Su;Park, Jae-Hak;Hwang, Jung-Kyu
    • Proceedings of the KSR Conference
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    • pp.1214-1221
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    • 2011
  • It is an well-known fact that dynamic properties should be considered in design and maintenance of civil structures undergoing dynamic force such as rail track. For designing of the rail tack structures, dynamic properties of track bed soil such as shear modulus (G) and damping coefficients(D) obtained in small to medium range of shear strain must be known. In general, small size sample of D=5 cm and H=10cm has been used mostly for test convenience. However, ratio of largest particle diameter of the soil to sample diameter is very important and affects to the values of dynamic soil properties in track bed. In this study, an RC/TS test apparatus was built and was run for testing a medium size soil sample that can handle with compacted soil sample up to 10 cm diameter and 20 cm height.

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Estimation of Characteristic of the Soil Physical using the Pipe Type Soil Sampler (원관형 토양샘플러를 이용한 토양물리특성 추정)

  • Ryu, Ji Hyun;Jung, Myung Kwan;Park, Seung Ki
    • Journal of The Korean Society of Agricultural Engineers
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    • v.62 no.1
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    • pp.95-104
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    • 2020
  • The purpose of this study is to develop a pipe type soil sampler that can easily collect soil cross section servey and soil samples to conduct ecological environment surveys while minimizing ecological disturbance in the area subject to soil survey. Furthermore, this study develop the exponential type estimation specific weight formula (ESWF) that uses pipe type soil sampler to easily carry out soil cross section survey and soil sample while estimating the specific weight of the area using water content and soil sample length variation ratio (SLVRs) and to obtain apparent specific gravity, hardness, and max. porosity which are used as growth of corps and ecological environment index. The calibration results of ESWF showed a high degree of significance, with NSE for actual specific weight (γ0) and calibration estimation specific weight (γec) 0.95, R2 for 0.954, and RMSE for 0.051. The verification results of ESWF showed a high significance, with NSE for actual specific weight (γ0) and verification estimation specific weight (γev) 0.881, R2 for 0.978, and RMSE for 0.055.

Amelioration of Soil Acidified by Air Pollutant around the Industrial Complexes (대기오염으로 산상화된 공업단지 주변 토양의 개량)

  • 이창석;김진영;유영한
    • The Korean Journal of Ecology
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    • v.21 no.3
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    • pp.313-320
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    • 1998
  • Ameliorating effects of dolomite and sludge on the polluted soil sampled from Ulsan and yeocheon Industrial Complexes were investigated. Ameliorating effects were analysed by changes of soil properties and plant growth after treatment of dolomite and sludge. Soil properties were investigated by analysing organic matter, N, P, K, Ca and Mg contents and pH. Growth of sample plants was investigated by leaf area calculated from length and breadth of leaves and by biomass from diameter and height of sample plants. Quercus serrata and Celtis sinensis selected as tolerant plants in field survey were used as experimental plants. Treatment with dolomite showed ameliorating effects by increassing n, Ca, and Mg com\ntents, and pH of soil and by decreasing Al content. Treatment of sludge showed similar effects by increasing N, Ca, Mg and organic matter contents, and by decreasing A1 content. But treatment of sludge did not show any effect on pH. Both soil ameliorators showed accelerating effects on the growth of experimental plants in Ulsan soil. But those effects in Yeocheon soil were somewhat different. Treatment of sludge showed accelerating effects of the growth of both sample plants but dolomitic liming did not so. From those results, we confirmed availability of sludge, a kind of industrial waste, as one of ameliorators of the polluted soil. In addition, we recognized that soil properties had to be considered to select soil ameliorators suitable for restoration of degraded ecosystems.

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DEM analyses of the mechanical behavior of soil and soil-rock mixture via the 3D direct shear test

  • Xu, Wen-Jie;Li, Cheng-Qing;Zhang, Hai-Yang
    • Geomechanics and Engineering
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    • v.9 no.6
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    • pp.815-827
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    • 2015
  • The mechanical behavior of soil and soil-rock mixture is investigated via the discrete element method. A non-overlapping combination method of spheres is used to model convex polyhedron rock blocks of soil-rock mixture in the DEM simulations. The meso-mechanical parameters of soil and soil-rock interface in DEM simulations are obtained from the in-situ tests. Based on the Voronoi cell, a method representing volumtric strain of the sample at the particle scale is proposed. The numerical results indicate that the particle rotation, occlusion, dilatation and self-organizing force chains are a remarkable phenomena of the localization band for the soil and soil-rock mixture samples. The localization band in a soil-rock mixture is wider than that in the soil sample. The current research shows that the 3D discrete element method can effectively simulate the mechanical behavior of soil and soil-rock mixture.

GC-MS/Ms Analysis of Benzo(a)pyrene by Ion Trap Tandem Mass Spectrometry

  • Nam, Jae-Jak;Lee, Sang-Hak
    • Bulletin of the Korean Chemical Society
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    • v.23 no.8
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    • pp.1097-1102
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    • 2002
  • The mass spectrometry using an ion trap tandem mass spectrometer has been investigated to find optimum conditions for the analysis of benzo(a)pyrene (3,4-benzpyrene). The applicability to a real soil sample was also investigated to verify the usef ulness of the MS/MS (or collision induced dissociation, CID) analysis. The optimum CID condition was 1.5 and 0.45 for the RF excitation voltage and the q value, respectively. For comparison, CID and EI were applied to the analysis of a soil sample. CID analysis was more sensitive than EI analysis of the soil sample. The limit of detection (LOD) of benzo(a)pyrene was 3.18 ng mL-1 and 0.85 ng mL,-1 for EI and MS/MS analysis, respectively. The precision at the soil sample for EI and CID showed relative standard deviations of 6.1% and 4.1%, respectively, and the concentrations were 168 ㎍ kg-1 and 162 ㎍ kg-1 , respectively.

지중오존산화시 토양유기물질과 수분이 토착미생물의 생존과 재성장에 미치는 영향

  • 손규동;정해룡;최희철;김수곤;양지원
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • pp.334-337
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    • 2003
  • This study was carried out to investigate the effect of soil properties, such as soil organic matter(SOM) content and water content on die-off and regrowth of indigenous microbes due to in-situ ozonation. Four different soils were collected and the soil samples applied to different ozonation time(0-360 min) were incubated during 4 weeks. Population of the indigenous microbes was monitored during incubation period. The number of indigenous microbes in all samples dramatically decreased (more than 90%) within 30 minutes of ozone injection. With increased ozonation time by 360 minutes, the number of the indigenous microbes decreased by 99.99% in all samples. Die-off of the indigenous microbes due to ozone treatment was inversely proportional to SOM and water content. Especially, sample 3 and Sample 4 containing relatively high SOM content and water content showed high regrowth rate, and this resulted from the increase of water soluble and biodegradable organic fraction in soil water after ozone treatment. Soil sample ozonated for 360 minutes showed minor increase in microbial population during 4 weeks of incubation period.

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