• 한국지반공학회논문집
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• 제26권4호
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• pp.59-68
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• 2010

파이핑은 제체 내부 침식의 한 형태로서 토립자의 진행성 유출에 기인하며 균열이 발생한 댐 뿐만 아니라 용해성 재료로 인하여 수년 동안 만족스런 거동을 보인 댐들에서도 발생한다. 파이핑 현상은 필댐의 붕괴 원인의 약 50%를 차지하고 있으며 필댐 관리의 주요항목이나, 이에 대한 체계적인 평가에는 다소 어려움이 있다. 이에 본 연구에서는 파이핑 현상에 대한 비파괴 탐지를 위한 전기비저항 탐사기법의 적용성을 파악하기 위해 대청댐 비상여수로 건설을 위해 해체되는 부댐에 파이핑 모사시험과 전기비저항 모니터링을 수행하였다. 제체에 수평공을 천공하여 인공적인 유로를 만들고 저수지 물을 유입시켜 실규모 파이핑 현상을 모사하였으며, 파이핑 현상 모사 시험전과 시험 중 측정한 전기비저항값을 비교한 결과 파이핑 발생 시 측정한 전기비저항값이 조금 더 큰 변화를 보임으로써 전기비저항 모니터링 탐사는 실제 담수되어 있는 제체의 파이핑 현상을 효과적으로 탐지할 수 있을 것으로 판단된다.

• The Korean Journal of Ecology
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• 제16권4호
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• pp.439-457
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• 1993

본 연구는 식물사회학적 방법에 의해 경상북도 안동군 임하댐 유역의 삼림식생을 분류하고 그 환경조건을 해석할 목적으로 실시되었다. 그 결과 다음의 4군락이 식별되었다: 소나무군락, 굴참나무-졸참나무군집, 아까시나무-닭의 장풀군락, 일본잎갈나무군락. 이중에서 소나무군락은 특히 인위적 영향이 미친 정도에 따라 다시 억새조성군, 산거울 조성군, 전형조성군 등 3하위단위로 세분되었다. 이들 삼림군락에 출현한 유관속식물은 총 63과 144속 191종 30변종으로 밝혀졌다. 이 연구에서 식별된 각 군락의 상관적, 종조성적 특징 및 고도, 경사, 지형, 토양과 같은 생육지의 환경조건이 기술되었다. 또, 상관적, 종조성적 특징과 함께 생활형의 분석 및 토양분석을 통하여 조사지에 있어서 일련의 천이경도를 명백히 하였다. 이와 관련한 삼림군락의 천이계열은 아까시나무-？의 장풀군락.일본잎갈나무군락\longrightarrow소나무군락\longrightarrow굴참나무-졸참나무군집\longrightarrow신갈나무군락의 순으로 밝혀졌다. 마지막으로 본 연구를 통해 귀납되는 사항으로서 댐의 건설을 전후한 자연생태계의 보전 방향이 제시되었다.

• Geomechanics and Engineering
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• 제9권4호
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• pp.483-498
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• 2015

This article describes a new in-situ load test called the Hydraulic Cylinder Test (HCT) and its application to determine the geotechnical properties of soil-rock mixtures. The main advantages of the test are its easy implementation, speed of execution and low-cost. This article provides a detailed description of the equipment and the test procedure, and examines a case study of its application to determine the geotechnical properties of an earth-filled dam for a tailings pond. The containment dams of the ponds are made from blocks of gypsum and marl, obtained from the excavation of the ponds, mixed in a matrix of sands and clays. The size of the rocks varies between 1 and 30 cm. The HCT is particularly useful for determining the geotechnical properties of this type of soil-rock mixture. Nine HCTs were carried out to determine its strength (c, ${\phi}$) and deformation (B, G) properties. The results obtained were validated using the Bim strength criterion, recently proposed, and some pressure meter tests carried out beforehand. The properties obtained are used to analyze the stability of the dam using computer simulations and a modification to its design is proposed.

• 한국농공학회지
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• 제38권4호
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• pp.125-136
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• 1996

In order to investigate the characteristics of gravity drainage for geotextile, small-scale model tests for the geotextile chimney drain of earth dam which is a typical type of gravity drainage were carried out using 15 kinds of nonwoven and composite geotextiles. According to the results of this study, the drainage discharge of geotexgile drain generally increases with exponential function as hydraulic head increases and the increasing rate is greater in the coarser soil of dam material. It has a trend to increase when the construction slope of geotextile drain is steeper and the number of layers of geotextile is more. The relationship between the transmissivity of geotextile and the drainage discharge has positive correlation and the rate of increase is greater in the coarser soil. The geotextile products must be carefully selected in consideration of transmissivity of geotextile when the soil to be drained is coarser and the seepage flow is relatively high. Most of staple fiber nonwoven geotextile used in this study are found to be appropriate for drainage purpose. Among them, the composite geotextile the type of which geotextile is evaluated to be the most excellent material. But the geotextile of low permeability such as filament thermal bonded and filament spunbonded nowovens closely examined their transmissivity especially to be used for drainage function.

• 한국환경보건학회지
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• 제16권2호
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• pp.83-87
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• 1990

This study was carried out to investigate the pollution of heavy metals in soil of seven stations from the upper spot (Yeungchun Dam) of Kumho River to the downstream(Gangchang Bridge). The results obtained were as follows: 1. The content of heavy metals in soil of Kumho River basin was highest at Gangchang Bridge [expresed in $\mu$g/g : Mn(246.0), Cd(1.90), Fe(551.2), Cu(108.2), Zn(86.4), Cr(80.2), respectively]. Whereas, the content of heavy metals expect for Mn, Cu was lowest at Yeungchun Dam [Cd(0.40), Fe(548.0), Zn(30.7), Cr(6.2), respectively] Also, the content of Cr, Zn was increased when the sampling areas are changed from upstream to downstream except for Hayang Bridge, and Hayang Bridge was the diverging point of the heavy metals content. 2. There were relatively correlated between Mn : FE, Cu, Zn, Cr, Fe : Cu, Zn, Cr(0.40 < $\left$\mid${r}\right$\mid$$ < 0.70), and were high correlated between Cd : Mn, Fe, Cu, Zn, Cu : Zn, Zn : Cr(0.70 < $\left$\mid${r}\right$\mid$$ < 0.90). Particularly, there was higest correlated between Cd : Cr, Cu : Cr(0.90< $\left$\mid${r}\right$\mid$$ < 1.0)

• 대기
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• 제22권3호
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• pp.357-365
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• 2012

High spatio-temporal resolution hydrologic components can give important information to monitor natural disaster. The objective of this study is to create high spatial-temporal resolution gridded hydrologic components using TOPLATS distributed land surface model and evaluate their accuracy. For this, Andong dam basin is selected as study area and TOPLATS model is constructed to create hourly simulated values in every $1{\times}1km^2$ cell size. The observed inflow at Andong dam and soil moisture at Andong AWS site are collected to directly evaluate the simulated one. RMSEs of monthly simulated flow for calibration (2003~2006) and verification (2007~2009) periods show 36.87 mm and 32.41 mm, respectively. The hourly simulated soil moisture in the cell located Andong observation site for 2009 is well fitted with observed one at -50 cm. From this results, the cell based hydrologic components using TOPLATS distributed land surface model show to reasonably represent the real hydrologic condition in the field. Therefore the model driven hydrologic information can be used to analyze local water balance and monitor natural disaster caused by the severe weather.

• 자원환경지질
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• 제55권5호
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• pp.439-445
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• 2022

하천퇴적물에 포함된 유기 오염물질의 기원은 다양하지만 주로 자연 기원의 산토양과 인위적 기원인 우분으로 구분할 수 있다. 영주댐 유역 토일천의 하천퇴적물에 포함된 유기오염물질의 기여도를 평가하기 위하여 산토양과 우분 및 하천퇴적물의 질소와 탄소 동위원소 분석을 수행하였다. 탄소동위원소비(δ¹³C) 평균값은 하천퇴적물 -25.17‰, 우분 -22.34‰, 산토양 -26.39‰으로 하천퇴적물은 산토양의 영향을 조금 더 받은 것으로 판단된다. 질소동위원소비(δ¹⁵N) 평균값은(‰)는 하천퇴적물 9.46‰, 산토양 1.99‰, 우분 19.53‰이다. 질소동위원소 분석결과에 의하면 토일천 하천 퇴적물은 자연기원의 산토양보다 인위적 기원인 우분의 기여도가 약간 더 높은 것으로 추정된다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제27권5호
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• pp.1-9
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• 2022

A correlation analysis was performed to investigate differences in the response of surface water and groundwater to drought using the Standardized Precipitation Index (SPI). Water level data of 20 agricultural reservoirs, 4 dams, 2 rivers, and 8 groundwater observation wells were used for the analysis. SPI was calculated using precipitation data measured at a nearby meteorological station. The water storage of reservoirs and dams decreased significantly as they responded sensitively to the drought from 2014 to 2016, showing high correlation with SPI of the relatively long accumulation period (AP). The responses of rivers varied greatly depending on the presence of an upstream dam. The water level in rivers connected to an upstream dam was predominantly influenced by the dam discharge, resulting in very weak correlation with SPI. On the contrary, the rivers without dam exhibited a sharp water level rise in response to precipitation, showing higher correlation with SPI of a short-term AP. Unlike dams and reservoirs, the responses of groundwater levels to precipitation were very short-lived, and they did not show high correlation with SPI during the long-term drought. In drought years, the rise of groundwater level in the rainy season was small, and the lowered water level in the dry season did not proceed any further and was maintained at almost the same as that of other normal years. Conclusively, it is confirmed that groundwater is likely to persist longer than surface water even in the long-term drought years.

• Journal of the Korean Data and Information Science Society
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• 제24권2호
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• pp.401-408
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• 2013

Soil moisture is a very important variable in various area of hydrological processes. We predict the soil moisture using a support vector regression. The model is trained and tested using the soil moisture data observed in five sites in the Yongdam dam basin. With respect to soil moisture data of of four sites-Jucheon, Bugui, Sangieon and Ahncheon which are used to train the model, the correlation coefficient between the esimtates and the observed values is about 0.976. As the result of the application to Cheoncheon2 for validating the model, the correlation coefficient between the estimates and the observed values of soil moisture is about 0.835. We compare those results with those of artificial neural network models.

• 한국광물학회지
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• 제19권1호통권47호
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• pp.49-61
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• 2006

본 연구는 댐으로 유입되는 하천수의 수질과 부유물질의 특성 분석을 통하여 댐의 탁수발생원인을 환경지질학적으로 규명하는 데 있다. 이를 위하여 2004년 5월부터 8월까지 3회에 걸쳐 가창댐의 본 댐 유역, 수변과 상류지역의 토양, 암석, 유입하천을 대상으로 댐 원수와 하천수, 토양, 암석, 부유물질의 특성을 ICP, IC, 입도분석기, XRD, SEM로써 분석하였다. 상류에서 하류로 갈수록 EC, 탁도, 양이온, 음이온의 농도가 증가하는데, 이는 풍화와 같은 지질학적인 영향으로 이온들의 총량이 증가하기 때문이다. 부유물과 토양내의 주 광물조성은 질석, 일라이트, 카올리나이트, 석영, 장석, 철수산화물 등이었다. 토양의 경우, 상류에서 하류로 갈수록 세립질 10% 구간(d10)의 입자의 양이 약간 증가하며, 부유물은 댐에 가까워질수록 질석의 함량이 증가한다. 그러나 본 유역을 구성하는 암석은 대부분 유사함을 보이고 이러한 지질분포특성에 의하여 부유물과 토양의 광물조성의 변화는 거의 나타나지 않는다. 부유물을 구성하는 점토광물들은 주변의 토양 구성광물과 유사하며 주변 모암의 풍화작용에 의해 생성된 토양으로부터 유래된 것을 지시한다.