• 한국수자원학회논문집
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• 제49권12호
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• pp.971-980
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• 2016

일반적으로 배사에 비해서 준설은 경제적 부담이 크기 때문에 배사를 효율적으로 운영하는 것이 중요하다. 본 연구에서는 2차원 하상변동 모형인 Nays2DH를 이용하여 홍수기 운영수위에 따른 배사효율을 낙동강에 위치한 달성보를 중심으로 분석하였다. 분석결과, 가동보의 수 만큼 배사수가 형성되었으며, 배사수로 상류에는 퇴적이 발생하는 것으로 나타났다. 또한, 홍수기 운영수위를 EL. 14.5 m로 운영하는 것이 EL. 14.0 m로 운영하는 것에 비해서 배사효율이 약 4.6% 증가하여 퇴사가 약 4.5% 감소하는 것으로 나타났다. 본 연구에서 분석한 홍수기 운영수위에 따른 배사효율의 변화를 고려한다면, 저수지 퇴사 저감 및 준설주기의 장기화가 가능할 것으로 판단된다.

• 한국수자원학회논문집
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• 제31권1호
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• pp.95-103
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• 1998

댐 퇴사량 예측방법은 수리학적 메커니즘을 이용하는 방법과 실측자료를 설계치로 적용하는 경험적 방법으로 구분할 수 있다. 전자는 물리적 해석방법으로 단기간에 이루어지는 현상을 규명하는데 적용할 수 있으며, 후자는 댐사수량 결정등 장기적인 설계변수 추정에 용이하게 이용할 수 있다. 이중 경험적 자료인 배사비 곡선식을 이용하면 월단위의 저수지 운영이 가능하며, 저류량에 대응하는 퇴사량을 정보변수로 추적하면 퇴사관리의 최적운영이 가능하다. 이와 같은 접근방법은 퇴사량에 의하여 시간적으로 변하는 댐 유효저수용량을 최적으로 관리할 수 있는 운영방안을 제공할 수 있다. 본 연구는 배사비 곡선을 이용한 장기 댐 퇴사량 예측방법을 제시하고 잇다. 개발된 방법을 중국 황하유역에 위치한 분하댐을 대상으로 장기간의 댐 운영을 모의하여 예상되는 퇴사량과 용수공급능력 분석에 적용하였다.

• International Journal of Ocean System Engineering
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• 제2권2호
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• pp.71-81
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• 2012

Several methods have been proposed to control the sedimentation process. These include catchment management, flushing, sluicing, density current venting, and dredging. Flushing is used to erode previously deposited sediments. In pressurized flushing, the sediment in the vicinity of the outlet openings is scoured and a funnel shaped crater is created. In this study, the effect of localized vibrations in the sediment layers on the dimensions of the flushing cone was investigated experimentally. For this purpose, experiments were carried out with two bottom outlet diameters, five discharge releases for each desired water depth, and one water depth above the center of the bottom outlets. The results indicate that the volume and dimensions of the flushing cone are strongly affected by localized vibrations.

• 한국물환경학회지
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• 제22권6호
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• pp.1094-1100
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• 2006

In this study, the reservoir sediment reduction methods for long-term operation are proposed by the analysis of both sediment deposit characteristics and sediment reduction effect by each method. To that end, a flowchart for sediment analysis in reservoir is established and sediment deposit is simulated by SMS-SED2D model. The sediment reduction methods which are sediment passing (sluicing), flushing, trapping, bypassing and mechanical removal are used. From the simulation results, the effective method for sediment reduction is operation which is coupled by both sediment passing with sand gate and sediment trapping with debris dam. And If sediment flushing will be used once a year after 50 years, conservation storage can be secured until 100 years after dam construction.

• 국제학술발표논문집
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• The 3th International Conference on Construction Engineering and Project Management
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• pp.168-172
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• 2009

Shihmen reservoir was started in May 1963. The main purposes of Shihmen reservoir are for agriculture, power supply, flood control and tourism. Shihme Asn dam is an earth dam. Its crown height is 133m above mean sea level, with length 360 m, watershed 763.4 km², and maximum volume 309 million cms. Turbidity in Shihmen dam was severely affected by typhoons Aere (2004) and Masa (2005). Increased deposition after Aere was 28 million cms. Turbidity at Shihmen Canal Inlet is 3000 NTU (Nephelometry Turbidity Unit). Sediment sluicing strategies for downstream channel are demanded. Therefore, diversionary sediment preventing channel is planned in the upstream of Shihmen reservoir. Finally, turbid flow in tunnel channel is bypassed and diverted its flow down to downstream.

• 한국환경과학회지
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• 제13권12호
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• pp.1089-1102
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• 2004

Seasonal variation of biogeochemical characteristics was determined in Lake Shihwa from October 2002 to August 2003. When the lake was artificially constructed for the freshwater reservoir in 1988, the development of the strong haline density stratification resulted in two-layered system in water column and hypoxic/anoxic environment prevailed in the bottom layer due to oxidation of accumulated organic matters in the lake. Recently, seawater flux to the lake through the sluice has been increased to improve water quality in the lake since 2000, but seasonal stratification and hypoxic bottom layer of the lake still developed in the summer due to the nature of artificially enclosed lake system. As the lake is still receiving tremendous amount of organic matters and other pollutants from neighboring streams during the rainy summer season, limited seawater flux sluicing into the lake may not be enough for the physical and biogeochemical mass balance especially in the summer. The excess of accumulated organic matters in the bottom layer apparently exhausted dissolved oxygen and affected biogeochemical distributions and processes of organic and inorganic compounds in the stratified two-layered environment in the summer. During the summer, ammonia and dissolved organic carbon remarkably increased in the bottom layer due to the hypoxic/anoxic condition in the bottom layer. Phosphate also increased as the result of benthic flux from the bottom sediment. Meanwhile, dissolved organic carbon showed the highest value at the upstream area and decreased along the salinity gradient in the lake. In addition to the sources from the upstream, autochthonous origin of particulate organic carbon from algal bloom in the lake might be more important for sustaining aggravated water quality and development of deteriorated bottom environment in the summer. The removal of trace metals could be attributed to scavenging by strong insoluble metal-sulfide compounds in the hypoxic/anoxic bottom layer in the summer.