• 산업기술연구
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• 제25권A호
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• pp.3-14
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• 2005

In order to accurately analyze the detailed hydraulic characteristics of the curved channel in the downstream of dam with the hydraulic structures such as bridge piers, RMA2 model which is one of two-dimensional models is applied to ChunCheon dam downstream curved channel. A series of hydraulic model tests are carried out for comparison studies. HEC-RAS model is also applied to the same site. There are no errors when velocities and water levels resulted from HEC-RAS model RMA2 model are compared with those of hydraulic model test on the straight channel. But, it is found that results of RMA2 model have a better agreement with those of hydraulic model test than those of HEC-RAS model on the curved channel with bridge piers. Additionally, RMA2 model can be predicted the eddy phenomena around bridge piers of the curved channel.

• 대한토목학회논문집
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• 제33권2호
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• pp.537-548
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• 2013

본 연구에서는 2006년 홍수시 충주댐 운영에 따른 댐 상 하류의 홍수위 상승영향을 정량적으로 분석하기 위하여 팔당댐 상류의 한강 본류에 위치한 충주댐을 기준으로 상류구간과 하류구간으로 구분하고, 1995년부터 2008년까지의 홍수사상을 대상으로 모형을 검보정함으로써 수리학적 모형을 구축하였다. 구축된 모형을 이용하여 충주댐의 유무를 가정하여 충주댐의 홍수조절효과를 검토하고, 방류량의 변화에 따른 상 하류 주요지점의 수위 상승영향을 정량적으로 분석하였다. 분석결과, 2006년 홍수시 충주댐의 운영이 비교적 적절하게 수행되었음을 확인하였으나, 충주댐의 홍수조절효과는 댐 하류구간에 집중되어 있어 댐 상류 홍수피해 저감을 위한 제도적 보완이 필요한 것으로 분석되었다. 이러한 문제점을 해결하기 위하여 기존 댐 배수구간 상류 하천의 기점수위 결정방법의 한계를 검토하였으며, 댐 배수구간과 상류 하천의 계획홍수량 불연속을 반영할 수 있는 기점수위 결정방법을 제안하였다. 제안된 방법은 댐 상류하천의 홍수피해 저감을 위한 설계 및 홍수피해 발생시 피해원인 분석에 활용될 수 있을 것이다.

• Structural Engineering and Mechanics
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• 제36권4호
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• pp.481-497
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• 2010

The shaking table tests were conducted on two small-scale models (Model 1 and Model 2) to examine the earthquake-induced damage of a concrete gravity dam, which has been planned for the construction with the recommendation of the peak ground acceleration of the maximum credible earthquake of 0.42 g. This study deals with the numerical simulation of shaking table tests for two smallscale dam models. The plastic damage constitutive model is used to simulate the crack/damage behavior of the bentonite-concrete mixture material. The numerical results of the maximum failure acceleration and the crack/damage propagation are compared with experimental results. Numerical results of Model 1 showed similar crack/damage propagation pattern with experimental results, while for Model 2 the similar pattern was obtained by considering the modulus of elasticity of the first and second natural frequencies. The crack/damage initiated at the changing point in the downstream side and then propagated toward the upstream side. Crack/damage accumulation occurred in the neck area at acceleration amplitudes of around 0.55 g~0.60 g and 0.65 g~0.675 g for Model 1 and Model 2, respectively.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
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• pp.361-364
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• 2005

The use of remotely sensed data and geographic information system (GIS) to develop conservation-oriented watershed management strategies on Imha Dam, Korea, is presented. The change of land use for study area was analyzed using multi-temporal Landsat imagery. A soil loss model was executed within a GIS environment to evaluate watershed management strategies in terms of soil loss. In general, remotely sensed data provide efficient means of generating the input data required for the soil loss model. Also, GIS allowed for easy assessment of the relative erosion hazard over the watershed under the different land use change options. The soil loss model predicted substantial declines in soil loss under conservation-oriented land management compared to current land management for Imha Dam. The results of this study indicate that soil loss potential (5,782,829 ton/yr) on Imha Dam in 2003 is approximately 1.27 times higher than that (4,557,151 ton/yr) in 1989. This study represents the first attempt in the application of GIS technology to watershed conservation planning for Imha Dam. The procedures developed will contribute to the evolution of a decision support system to guide the land planning and dam management in Imha Dam.

• 한국지진공학회논문집
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• 제3권1호
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• pp.123-132
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• 1999

댐-호소 계의 지진응답해석에 있어서의 어려운 문제 중 하나는 댐 상류방향으로의 에너지 방사를 적절하게 처리하는 것이다 본 논문에서는 깊이가 일정한 호소 원역으로의 에너지 방사를 잘 모델링할 수 있는 전달경계를 제시하였다 개발된 방법에서 수면파의 영향을 고려하였으며 호소-지반의 상호작용을 근사적으로 표현할수 있는 흡수경계조건도 도입하였다 댐과 호소의 경계면이 지표면에 수직하고 호소의 깊이가 일정할 경우에는 제안된 전달경계를 댐체의 모델에 직접 연결할 수 있다 댐체는 선형탄성거동을 가정하여 유한요소로 모델링 하였다 얻어진 댐-호소 계의 운동방정식을 이용하여 댐의 지진응답특성을 조사하였다

• 한국산학기술학회논문지
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• 제9권5호
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• pp.1334-1343
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• 2008

본 연구는 수계별 한정된 수자원의 효율적 관리를 위한 기존댐의 연계운영과 병행하여 댐 상·하류 유출을 고려한 종합적인 수자원관리방안 수립의 필요성이 대두됨에 따라, 고수기 및 저수기 댐 상 하류의 수계주요지점에 대한 하천유출상황을 모의할 수 있는 유출모형을 구성하는데 목적이 있다. 또한 장 단기적으로는 기존 모형을 검토하여 한국수자원공사의 "한강수계 댐 통합운영계획 수립" 업무에 활용될 수 있도록 하는데 있다. 본 연구에서는 한강수계의 소유역을 24개로 분할하였고 강우의 공간 분포를 작성하기 위해 151개의 강우관측소를 이용하여 강우자료를 정리하였다. 한강수계의 주요 제어지점으로 소양강댐, 충주댐, 충주 조정지댐, 횡성댐, 화천댐, 춘천댐, 의암댐, 청평댐, 팔당댐을 선정하였다. SSARR(Streamflow Synthesis and Reservoir Regulation) 모형을 기반모형으로 선정하여 모형의 입력자료를 작성하고 2002년의 수문자료를 이용하여 매개변수의 민감도 분석을 수행하였다. 민감도 분석 결과, 유역유출과 관련된 매개변수 중 토양습윤상태별 유출율, 침투량별 지하수유입률 및 지표수와 복류수를 분리하는 매개변수가 비교적 큰 민감도를 나타내었다.

• Coupled systems mechanics
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• 제7권3호
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• pp.333-351
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• 2018

In the present paper, the behavior of the Karaj double curvature arch dam is studied focusing on the effects of structural nonlinearity on the responses of the dam body when an underwater explosion occurred in the reservoir medium. The explosive sources are located at different distances from the dam and the effects of the cavitation and the initial shock wave of the explosion are considered. Different amount of TNT are considered. Two different linear and nonlinear behavior are assumed in the analysis and the dam body is assumed with and without contraction joints. Radial, tangential and vertical displacements of the dam crest are obtained. Moreover, maximum and minimum principal stress distributions are plotted. Based on the results, the dam body responses are sensitive to the insertion of joints and constitutive model considered for the dam body.

• Water Engineering Research
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• 제3권4호
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• pp.215-234
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• 2002

Uncertainty in dam breach flood routing results was analyzed in order to provide the basis fer the investigation of their effects on the flood damage assessments and dam safety risk assessments. The Monte Carlo simulation based on Latin Hypercube Sampling technique was used to generate random values for two uncertain input parameters (i.e., dam breach parameters and Manning's n roughness coefficients) of a dam breach flood routing analysis model. The flood routing results without considering the uncertainty in two input parameters were compared with those with considering the uncertainty. This paper showed that dam breach flood routing results heavily depend on the two uncertain input parameters. This study indicated that the flood damage assessments in the downstream areas can be critical if uncertainty in dam breach flood routing results are considered in a reasonable manner.

• 한국물환경학회지
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• 제24권2호
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• pp.239-246
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• 2008

In this study, an optimized deterministic water-quality model was constructed to estimate water quality of a river and lake in the upstream basin of a dam. A stochastic water-quality analysis using reliability analysis technique was applied to the model. The model was tested in the 13.9 km reach from Maeil stage station of Kyechun to Hoengsung Dam of Sum River. After finding hydraulic characteristics from nonuniform flow analysis, Broyden-Fletcher-Goldfarb-Shanno (BFGS) optimization technique for model calibration was applied to determine optimum reaction parameters, and model verification was performed based on these. The stochastic model, using Mean First­Order Second­-Moment (MFOSM) and Monte-Carlo methods, was applied to the same reach as the deterministic study. Variations of discharge and water quality in headwater were considered, as well as variations of hydraulic coefficients and reaction coefficients. The statistical results of output variables from MFOSM were similar to those from the Monte-Carlo method. Risk analysis using MFOSM and Monte-Carlo methods presented the probabilities of some locations in the Hoengsung Lake violating existing water-quality standards in terms of DO and BOD.

• 한국환경과학회지
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• 제17권11호
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• pp.1281-1293
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• 2008

This study aims at the estimation of dam failure time and dam failure scenario analysis of and applied to Yeoncheon Dam which was collapsed August 1st 1999, using HEC-HMS, DAMBRK-FLDWAV simulation model. As the result of the rainfall-runoff simulation, the lancet flood amount of the Yeoncheon Dam site was $10,324\;m^3/sec$ and the total outflow was $1,263.90\;million\;m^3$. For the dam failure time estimation, 13 scenarios were assumed including dam failure duration time and starting time, which reviewed to the runoff results. The simulation time was established with 30 minutes intervals between one o'clock to 4 o'clock in the morning on August 1, 1999 for the setup standard for each case of the dam failure time estimation, considering the arrival time of the flood, when the actually measured water level was sharply raising at Jeongok station area of the Yeoncheon Dam downstream, As results, dam failure arrival time could be estimated at 02:45 a.m., August 1st 1999 and duration time could be also 30 minutes. Those results and procedure could suggest how and when dam failure occurs and analyzes.