• 환경위생공학
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• 제16권4호
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• pp.77-89
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• 2001

The research is intended to evaluate the soil pollution quality of Chungbuk province with Soil Network which is executed every year. The survey executed with Soil Network in 1999 represented that the soil quality of Chungbuk province was relatively good as the average concentrations of contaminants in soil were Cd: 0.146 mg/17g, Cu: 3.143 mgHg, As: 0.636 mg/kg, Hg: 0.012 mg/kg, Pb): 4.505 mg/kg, $Cr^{+6}$ not detected, and the average pH was 6.1. The reckoned soil Pollution score (SPS) of Chungbuk province has been shown much low SPS distribution in the range from 1.6 to 141.7, average 31.0. However, it has been represented relatively high SPS distribution at Chungju, Tanyang, and Chinchon, respectively, It also huts represented high SPS distribution not only at agricultural area and waste area for the Pollution sources but at a paddy field and dry field for land use. The classification of soil pollution class(SPC) based on soil pollution score(SPS) was SPC 1 under 100 of SPS at 212 areas which were 98.6% of total 215 areas and SPC 2 over 100 of SPS at only three area left. There was no area exceeding soil pollution value among the whole Soil Network areas investigated, and the whole average for each items was much lower level th퍼n soil Pollution value was. When the average concentration of heavy metals and the average pH in soil of Chungbuk province are compared with the natural contents of that in Korea, the research is concluded that the average concentration of heavy met is relatively similar to the natural contents of that and the average pH in soil of Chungbuk province is a little higher than the natural contents of that. From this method, soil quality of most of the Soil Network area was estimated to be healthy.

• Journal of the Korean Wood Science and Technology
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• 제37권2호
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• pp.137-140
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• 2009

Chromated copper arsenate (CCA), a long history of successful preservative, have raised environmental concerns. Adsorption characteristics of domestic soils for chromium, copper, and arsenic were assessed by measuring distribution coefficient ($K_d$) values of these metal components in a laboratory scale. The results revealed that $K_d$ values were higher in chromium, followed by arsenic and copper in soil matrix. Different soil matrixes resulted in varying mobilities of CCA components. The values of $K_d$ for all three metals increased with organic matter contents. The results suggest that the mobility of metal components may be very limited to the surface area adjacent to CCA-treated wood due to their fairly large distribution coefficient ($K_d$). However, the metal components would be persistent and accumulated in the soil, resulting in high chemical concentration in service area of treated wood.

• 한국환경복원기술학회지
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• 제4권1호
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• pp.16-23
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• 2001

This study was conducted to analyse the relation between physical characteristics of soil surface and wild plants occurrence. Lots of natural occurrence on loamy soil and a little of natural occurrence on perlite. Those were used to observe the wild plants occurrence through the duration. Natural occurrence of wild plants were observed on uniform sand, perlite, loamy soil and 2cms loamy soil layer above the perlite. Uniform sand was compared with different height of drain ditch. The results of analysis were as followed. 1. Wild plants germinated on the uniform perlite layer, they did not grow larger. Because water in large pores of perlite surface drained rapidly and evaporated easily, therefore surface remained low moisture contents. 2. A lot of weed grew on 2cms loamy layer on perlite which stratified above the perlite layer. Because perlite had plenty of soil moisture and soil moisture moved easily from perlite to loamy soil layer. 3. Uniform loamy soil had similar occurrence on the uniform perlite. It was nearly same at surface moisture distribution but lower than layered loamy soil on perlite, and the vertical distributions at soil moisture was totally lower than 2cms loamy soil layer on perlite. 4. Wild plants were grew on uniform sand on different height of drain ditch. In this case, much more wild plants were grew on which had more higher drainage ditch. The number of wild plants occurred when it was affected by soil surface moisture, drain ditch and natural occurrence of wild plants. This could be controlled by layered soil at surface moisture. Therefore weed occurrence can control in planting ground, where soil layer would not be disturbed.

• Earthquakes and Structures
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• 제12권2호
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• pp.153-163
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• 2017

The underlying goal of the present paper is to investigate soil and structural uncertainties on impedance functions and structural response of soil-shallow foundation-structure (SSFS) system using Monte Carlo simulations. The impedance functions of a rigid massless circular foundation resting on the surface of a random soil layer underlain by a homogeneous half-space are obtained using 1-D wave propagation in cones with reflection and refraction occurring at the layer-basement interface and free surface. Firstly, two distribution functions (lognormal and gamma) were used to generate random numbers of soil parameters (layer's thickness and shear wave velocity) for both horizontal and rocking modes of vibration with coefficients of variation ranging between 5 and 20%, for each distribution and each parameter. Secondly, the influence of uncertainties of soil parameters (layer's thickness, and shear wave velocity), as well as structural parameters (height of the superstructure, and radius of the foundation) on the response of the coupled system using lognormal distribution was investigated. This study illustrated that uncertainties on soil and structure properties, especially shear wave velocity and thickness of the layer, height of the structure and the foundation radius significantly affect the impedance functions, and in same time the response of the coupled system.

• 한국토양비료학회지
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• 제42권5호
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• pp.348-354
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• 2009

제주도 지역을 대상으로 기후요인과 토양분포의 관계를 알아보기 위하여 기온, 강우량, 증발산량 등 기후요인을 이용하여 분석하였다. 온도를 기준으로 하여 중심지역의 Mesic상 지역과 주변부의 Thermic상 지역으로 구분하고, 월별 수분수지빈도를 기준으로 4개로 구분하여, 온도, 수분수지로 전체를 온대수분과 다지역(집단1), 난대수분과다지역(집단2), 난대수분균형지역(집단3), 난대수분부족지역(집단4), 난대수분매우부족지역(집단5)의 5개의 집단으로 구분할 수 있었다. 집단1에서 집단5로 갈수록 토양분류측면에서는 andisols, inceptisols, alfisols, ultisols의 분포 비중이, 토색측면에서는 흑색토양, 농암갈색토양, 암갈색토양의 분포비중이 높아지는 경향이었다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1999년도 봄 학술발표회 논문집
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• pp.357-364
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• 1999

The purpose of this study is to analysis the grain distribution and compaction characteristics of structural backfill with reclaimed soil. Five(5) reclaimed soil samples which passed #200 sieve have been used in the test. The study showed that the maximum dry density and the bearing value rate turned out to be becoming smaller when the more the quantity passed #200 sieve, the smaller the soil grain. The maximum dry density value calculated from the compaction md relative density test showed wet method > compaction method > dry method. The correlation coefficient between Rc and Dr based on the grain distribution and the compaction characteristics showed that the maximum dry density value by the wet method is little higher than the compaction method and dry method.

• The Korean Journal of Ecology
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• 제17권2호
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• pp.113-119
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• 1994

Vertical and horizontal distribution and seasonal changes of fine roots as well as inorganic nitrogen content in soil were determined in Quercus mongolica and Quercus acutissima stands in Mt. Taemosan, Seoul. The vertical distribution of fine rooth phytomass showed a power-functional decrease as descending soil depth. Fine root phytomass was 170 g $DM/m^2$(46%) and 225 g $DM/m^2$(47%) in top soil of 5 cm depth, and 370 g $DM/m^2$ and 480 g $DM/m^2$ from soil surface to 50 cm depth in Q. mongolica and Q. acutissima stands, respectively. Fine roots in relation to the distance from the nearest tree were evenly distributed horizontally in both stands. Fine roots phytomass in top soil of 5 cm depth reached a peak in June, and thereafter decreased gradually in both stands. Patterns of seasonal changes in fine root phytomass were closely related to inorganic nitrogen and moisture content.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2003년도 학술발표논문집
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• pp.163-166
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• 2003

In this study, a grouping of particle-size distributions(PSDs) by means of the fuzzy c-means clustering method(FCM) was presented. The classification was performed with the whole and the major soil series representing pedological origin. In case of the major soil series, PSDs were clustered as $2{\sim}4$ groups and the characteristics of clustering results were quite different between the soil series. It was found that the characteristics of PSDs at center of each class can be explained by formation process of each soil series. In case of whole soil data, PSDs were classified to 8 classes in which 4 classes were single mode and 4 classes were bimode distributions. Through this study, it is concluded that pedogenetic process is a plausible explanation for grain size distribution of soils.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2005년도 학술발표논문집
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• pp.423-428
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• 2005

If the load of constructing vehicles during the construction work acts on the road or the ground surface on the soft ground, due to the excess stresses in soils the trafficability of the vehicles influences the constructing efficiency, constructing period and so on. Stress distribution in soils is the very important element to design and to solve the problems of settlement, safety of foundations and trafficability of constructing vehicle in civil engineering. This research represents the comparative estimation of the actual and theoretical measurement on the underground stress of outer layer for each soil after the observation of each top soil layer for its vertical and horizontal stress in (1)homogeneous sand ground (2) weak stratum with the sand soil (3) weak stratum with gravel of the soil model, and it also investigates the effect of subsidence of ground by the repeated load. The underground stress turn out to be different in the value of theoretical and actual measurement after the trial examination of model.

• 대한지하수환경학회지
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• 제1권2호
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• pp.80-84
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• 1994

토양중 중금속의 수직분포비율과 토양특성과의 관계를 규명하기 위하여 중금속에 의한 토양 오염이 우려되는 연· 아연 광산지역 주변농경지 27개 지점을 선정하여 토양깊이별로 시료를 채취하여 중금속함량과 토양의 이화학적 특성을 조사하였다. 본 연구를 통하여 얻어진 결과는 다음과 같다. 1) 중금속 원소의 토심별 분포는 표토(0- l5 cm)에서는 42-51%, 15 -30 cm에서는 21-29%, 30-60 cm에서는 12-17%, 60-100 cm에서는 11-14%였다. 2) 비소는 사양토와 양토간의 차이가 인정되나 Cd, Cu, Pb, Zn은 토성간에 차이가 없었다. 3) 토심별 각 원소의 함량분포비와 토양의 화학성과의 관계를 보면 각 원소 모두 pH와는 높은 유의성있는 부의 상관을 보인 반면 유의성있는 정의 상관을 나타내었다. 4) Cd, Cu, Pb 및 Zn 은 모든 토심에서 각 원소간에 대부분 높은 상관이 있었고 특히 Pb와 Zn은 0-15 cm, 30-60 cm, 60-100 cm에서 Cd와 Zn은 15 -30 cm에서 높은 상관을 나타내었다.