• 한국농공학회:학술대회논문집
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• 한국농공학회 2005년도 학술발표논문집
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• pp.343-348
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• 2005

In this study, construction modulus, void ratio and settlement characteristics of 38 CFRD in domestic and foreign countries was investigated from monitoring data and the effect of field dry density and void ratio to dam body was analyzed. The standard void ratio of CFRD that can be easily used for dam designer and field engineer was proposed from the monitoring data. It was conformed that we can get the degree of compaction needed for reasonable compaction of dam body by calculating the field dry density from inverse operation of the standard void ratio. It was thought that the standard void ratio of CFRD is 0.2 as shape factor is under 4 and is 0.28 as shape factor is over 4.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 1999년도 추계 학술발표회 논문집 Proceedings of EESK Conference-Fall
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• pp.3-14
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• 1999

The Hyogoken-Nambu Earthquake of January 17, 1995 inflicted severe damage in the Hanshin and Awaji areas such as has never been seen in Japan in recent years. The safety inspections of the dams conducted in the area by site offices and dam experts immediately after the earthquake showed that there was no damage affecting the safety of the dams although slight damage was observed in several dams. The investigation also revealed that the peak accelerations at dam sites were much smaller than those at soil sites. The Ministry of construction organized the Committee on Evaluattion of Earthquake Resistance of Dams after the earthquake. The Committee confirmed through dynamic analysis that the dams designed in accordance with the present design criteria in Japan are safe under the magnitude of shaking that occurred close the source fault of the Hyogoken-Nambu Earthquake.

• Computers and Concrete
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• 제26권6호
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• pp.483-495
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• 2020

Dams are vital infrastructures that are expected to maintain their stability during seismic excitations. Accordingly, cemented material dams are an emerging type, which are being increasingly used around the world owing to benefiting from advantages of both earth-fill and concrete gravity dams, which should be designed safely when subjected to strong ground motion. In the present paper, the seismic performance of a cemented sand and gravel (CSG) dam is assessed using incremental dynamic analysis (IDA) method by accounting for two failure modes of tension cracking and base joint sliding considering the dam-reservoir-foundation interactions. To take the seismic uncertainties into account, the dam is analyzed under a suite of ground motion records and then, the effect of friction angle for base sliding as well as deformability of the foundation are investigated on the response of dam. To carry out the analyses, the Cindere dam in Turkey is selected as a case study, and various limit states corresponding to seismic performance levels of the dam are determined aiming to estimate the seismic fragilities. Based on the results, sliding of the Cindere dam could be serious under the maximum credible earthquake (MCE). Besides, dam faces are mostly to be cracked under such level of intensity. Moreover, the results indicate that as friction angle increases, probability of sliding between dam and foundation is reduced whereas, increases tensile cracking. Lastly, it is observed that foundation stiffening increases the probability of dam sliding but, reduces the tensile damage in the dam body.

• 한국지반공학회논문집
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• 제36권6호
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• pp.5-15
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• 2020

본 연구는 필댐에 설치된 간극수압과 댐의 저수위와의 상관관계를 통해 댐의 안정성 평가를 위한 간극수압계의 활용방안에 대해 다루고 있다. 이를 위해 필댐에 설치된 총 8개의 간극수압계에 대해서 주성분 분석을 수행한 결과, 3개의 군집으로 분류되었다. 이는 댐 제체 내에 형성되는 침윤선을 기준으로 내부, 외부, 상단으로 분류된 것으로 나타났다. 침윤선 내부에 위치한 A군집 내 간극수압계와 저수위와의 상관계수는 0.94~1.00로 강한 양의 선형관계를 나타냈다. 즉, 향후 A군집 내에 존재하는 간극수압계에 의해 해당 댐의 유지관리가 필요한 것을 의미한다. 또한, 저수위와 간극수압계에 대한 회귀분석을 수행한 결과, A군집의 결정계수가 0.89~0.99로 선형회귀 모형이 도출되었다. 따라서 저수위가 설명 변수로 고정될 때 간극수압의 예측이 가능하여 현재 계측된 값과의 비교를 통해 댐의 안전성 여부를 판단할 수 있는 것으로 나타났다.

• 한국지반공학회논문집
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• 제20권8호
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• pp.167-180
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• 2004

기존 흙댐의 저수 용량 확대를 위하여 댐의 높이를 숭상(嵩上)하는 경우 기존 댐체의 축조 재료와 동일한 재료가 아닌 콘크리트 표면 차수벽형 석괴댐(CfRD)의 차수벽 지지층에 대응하는 조립의 재료로 추가 성토를 수행하였다. 이를 가칭 콘크리트 표면 차수벽형 흙댐(CFED)이라 하고, 이런 형식의 댐에 대한 응력 및 변형 특성을 예측하기 위하여 Hyperbolic 모델을 이용한 유한요소 해석을 수행하였다. 수치 해석에 의한 예측치와 현장 계측치를 비교 분석한 결과 비교적 서로 잘 일치하는 것으로 나타나 댐체의 응력-변형 거동에 대한 유한요소 해석 결과는 신뢰성이 매우 높은 것으로 평가되었다. 따라서 해석 결과 나타난 최대 변위와 응력의 발생 지점 및 응력 집중 현상이 발생되거나 하중전이가 불규칙하게 나타나는 부분 등을 중심으로 댐체 시공시 정밀 현장 계측 관리를 수행한다면 합리적이고 효과적인 시공 관리 및 품질 관리가 될 것으로 기대된다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2009년도 세계 도시지반공학 심포지엄
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• pp.1037-1040
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• 2009

Using much most electricity electric resistivity survey by nondestructiveness inquiry enforcement design of country base equipment business and facilities preservation administration dimension electric resistivity survey sends and cause much effects in survey believability by electricity medium of survey personality survey contiguity that grasp base special quality by potential difference flowing current artificially in base. Is item that enforce in most in-suite although when make electric resistivity survey until present, electricity medium or effect research by electricity origination was gone much. There is shortcoming that must be difficult to know correct underground utilities establishment state in-suite in this research and do comparison examination running parallel drilling investigation to heighten believability of electric resistivity survey. Did to dam that censure data that regulate grading from construction and is censure construction which can know correctly interior base situation comparatively to electricity medium of interior and electricity eruption won of contiguity and base condition (base rock).

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2022년도 학술발표회
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• pp.86-86
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• 2022

While estuarine dams can develop freshwater resources and block the salt intrusion, they can result in increased sediment deposition in the estuary. The mechanism of increased sediment deposition in an estuary with an estuary dam is not well understood. To fill this knowledge gap, 7 ADCP measurements of flow and suspended sediment concentration (SSC) were collected along-channel in an estuary with an estuarine dam over a neap-spring cycle. Flow and SSC were used to calculate the sediment flux and sediment flux gradients. The results indicated that the cumulative sediment fluxes at all stations were directed landward. The along-channel sediment flux gradient was negative, which indicated deposition along the channel. The landward mean-flow fluxes were dominant in the deep portion of the channel near the estuary mouth, whereas landward correlation fluxes were dominant in the shallow portion of the channel near the estuarine dam. The tides were the dominant forcing driving the sediment fluxes throughout the estuary.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2005년도 학술발표논문집
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• pp.349-354
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• 2005

In this study, settlement characteristics of 23 CFRD was investigated from monitoring data and the method to estimate the crest settlements considering internal settlement during constructions was proposed. Moreover, crest settlement smaller than 20cm and deflection of face slab smaller than 20cm are not considered to be critical to the stability of large dam whose height is over 40m. Therefore, we assigned the region as safe zone that can be used as a guideline of maintenance of dam. These estimated data can be used in the design, construction and long-term maintenance in domestic CFRD hereafter.

• 한국환경과학회지
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• 제28권2호
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• pp.211-217
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• 2019

A Numerical modeling approach is usually applied to reproduce the physical phenomena of a fill dam-break. The accuracy of the dam-break model depends on the physical structure that defines input variables such as the storage volume, breach formation and progress, and the parameters of the model, which are subjective as they are prescribed by users. In this study, a sensitivity analysis was performed for the nonlinear breach progression curve that was already developed, which includes four parameters. The study focuses on the two of the parameters which control the breach forming time and peak discharge. The model is coupled with a two-dimensional flood simulation model (FLO-2D) to examine flood coverage and depth. It is generally observed that the parameter ${\beta}$ controls only the breach forming time, the parameter ${\gamma}$ is particularly sensitive to the peak flow.

• 한국지반환경공학회 논문집
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• 제16권8호
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• pp.21-35
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• 2015

본 연구에서는 국내 3개 필 댐의 ECRD(Earth Core Rock-fill Dams) 댐체의 코어존에 대한 건전성 평가를 목적으로 2차원 및 3차원 전기비저항 탐사를 수행하였다. 2차원 전기비저항 탐사 결과, 대부분의 점토재로 축조된 코어존은 $50{\sim}400ohm{\cdot}m$ 이하의 저비저항대로 나타났으며, 그 하부의 기반암은 $1,000ohm{\cdot}m$ 이상의 고비저항대로 나타났다. 또한 3차원 전기비저항 탐사 결과에 의하면 코어존의 연약대로 판단되는 $100ohm{\cdot}m$ 이하의 저비저항대의 공간적인 분포영역을 확인할 수 있었다. 아울러 코어존의 토질시료 특성을 파악하기 위하여 시추조사와 토질 실내시험을 수행하였다. 시추조사 시 굴착수에 의한 댐체 내의 구조적 훼손을 방지하기 위하여 무수보링 방법을 택하였다. 그 결과 저비저항대로 나타나는 코어존의 시료는 모두 통일분류상 CL에 해당되며, 일부 저비저항대에서는 함수비가 높은 포화상태의 시료가 관찰되었다. 이러한 결과를 통해 ECRD 댐체 코어존의 건전성 평가에 전기비저항 탐사와 무수보링의 적용성은 매우 효율적인 방법이라 판단된다.