• 한국농공학회논문집
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• 제56권6호
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• pp.1-9
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• 2014

In this study the pore water pressures were measured in sea dike constructed with the sand dredged in the sea, and they were analyzed with the hydraulic head loss rate to estimate quantitatively the state of blocking seepage in the sea dike embankment. Blocking state was expressed as the number between 0 and 1. the number of 1 means the state of perfectly blocking seepage and the number of 0 means the state of sea water being passing free. The deeper the installed position was the lower the hydraulic head loss rate was and the longer the seepage path length was the higher the hydraulic head loss rate was. The estimated R-squareds were close to 1, which means that the embankment was steady state without movement of soil particles.

• 한국농공학회지
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• 제35권2호
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• pp.43-56
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• 1993

The laboratory tests are performed on how the liquefaction potential of the sea dike structures on the saturated sand or silty sand seabed could be affected due to earthquake before and after construction results are given as follows ; 1. Earthquake damages to sea dike structures consist of lateral deformation, settlement, minor abnormality of the structures and differential settlement of embankments, etc. It is known that severe disasters due to this type of damages are not much documented. Because of its high relative cost of the preventive measures against this type of damages, the designing engineer has much freedom for the play of judgement and ingenuity in the selection of the construction methods, that is, by comparing the cost of the preventive design cost at a design stage to reconstruction cost after minor failure. 2. The factors controlling the liquefaction potential of the hydraulic fill structure are magnitude of earthquake(max. surface velocity), N-value(relative density), gradation, consistency(plastic limit), classification of soil(G & vs), ground water level, compaction method, volumetric shear stress and strain, effective confining stress, and primary consolidation. 3. The probability of liquefaction can be evaluated by the simple method based on SPT and CPT test results or the precise method based on laboratory test results. For sandy or silty sand seabed of the concerned area of this study, it is said that evaluation of liquefaction potential can be done by the one-dimensional analysis using some geotechnical parameters of soil such as Ip, Υt' gradation, N-value, OCR and classification of soils. 4. Based on above mentioned analysis, safety factor of liquefaction potential on the sea bed at the given site is Fs =0.84 when M = 5.23 or amax= 0.12g. With sea dike structures H = 42.5m and 35.5m on the same site Fs= 3.M~2.08 and Fs = 1.74~1.31 are obtained, respectively. local liquefaction can be expected at the toe of the sea dike constructed with hydraulic fill because of lack of constrained effective stress of the area.

• 한국농공학회:학술대회논문집
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• 한국농공학회 1998년도 학술발표회 발표논문집
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• pp.419-424
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• 1998

The deduction methods for forced displacement depths caused by sea dike construction often assumed the shape of forced displacements and heaving. To investigate the shape of forced displacements and heaving, a model tests was performed. Results of the tests are as follows; 1) The shape of forced displacements can be assumed ellipse. 2) The shape of heaving can not be assumed uniform shape like a circle and Extents of heaving was varied with the loading height and width. 3) The shape of forced displacements caused by step construction, pebble embankments and soil embankments, also investigated.

• 한국농공학회논문집
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• 제56권6호
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• pp.159-167
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• 2014

In this study the process of normalizing hydraulic head loss rate was developed for the purpose of estimation of seepage blocking state at each seepage segment in sea dike embankment. Pore water pressure sensors were installed with some interval along seepage path, then the hydraulic head loss rate at each segment between pore water pressure sensors was calculated, and then the calculated hydraulic head loss rate was normalized based on seepage path length. The comparison of normalized hydraulic head loss rates showed that the cross section of sea dike embankment was homogeneous approximately and the width of cross section was long enough to blocking tide water.

• 한국농공학회논문집
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• 제47권1호
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• pp.35-42
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• 2005

The research has been done to obtain a empirical equation for the depth of replacement by the analysis of data collected from 8 sea-dike construction sites of south coast of Korean peninsula. The correlation analysis results show that the depth of replacement was mainly dependent upon the height of embankment and the undrained shear strength of soft soil. The suggested regression equation was quite well predicted the depth of replacement and recommended to use under certain restrictions where the embankment height was less than 10m and under 0.2 kgf/cm^{2} of the undrained shear strength of soil.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 추계 학술발표회
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• pp.60-68
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• 2010

In this study, the seepage flow monitoring method by hydaulic head loss rate graph was developed for the purpose of monitoring the seepage flow from the see side or from the lake on sea dike in which seepage force was varied periodically. The hydraulic head loss rate was defined in this method. The value of the rate is in the range from 0 to 1. the value of 0 means perfectly free flow of seepage. the value of 1 means perfect waterproofing. The value of coefficient of determination in the hydraulic head loss rate graph closer to 1 means that the seepage flow way is stable. The value of coefficient of determination in the hydraulic head loss rate graph closer to 0 means that the hole may exist or the piping may be in the progress. The pore water pressure data measured in Saemangeum sea dike was analyzed with the developed method The result showed that the variation of seepage flow state was detected sensitively by this method and the interception effect of sea dike could be estimated quantitatively.

• 한국해안해양공학회지
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• 제8권2호
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• pp.204-214
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• 1996

본 연구의 목적은 새만금해역에서 방조제 축조에 따른 토사의 이동형태변화와 토사 확산을 알아보는 데 있다. 유동은 조석잔차류와 관측된 바람, 수온, 염분자료를 이용하여 계산되었다. 유동에 의한 토입자의 3차원적 거동은 Euler-Lagrange 방법으로 추적하였다. 방조제 축조에 따른 토사확산 및 이동 형태는 금강 하구 남쪽에서 고군산군도 북쪽에 대부분의 토사를 퇴적시켰다. 이것은 잔차류의 영향으로 판단된다.

• 한국해안해양공학회:학술대회논문집
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• 한국해안해양공학회 1995년도 정기학술강연회 발표논문 초록집
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• pp.139-140
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• 1995

The reclamation area of Saemangeum(Kunsan) located between 126。10´E - 126。50´ E and 35。35´N - 36。05´N at the western coast of Korea. The construction of the 33km sea dike is building in the Saemangeum area. When the construction of the sea dike in the coastal region takes plase, there exists, a certain amount of soil which is diffused by the tidal current. (omitted)

• 한국해양공학회지
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• 제20권3호
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• pp.61-66
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• 2006

The estuary has a very complex coastline and bottom topography. Before the close of floodgate, the Keum river estuary was deposited with sediment from the Keum river, created bythe construction of the Keum river estuary dike. So, a periodical dredging is necessary to assure water depth for boat entry and departure to Kunsan port. Theof this study is to find the change of tidal current of M2tide and the topography before and after construction at the Geum River estuary dike. The change of water depth is investigated by digitizing the sea map (No.305) of Kunsan port, which was edited by National Oceanographic Research Institute. The calculated co-range and co-tidal charts of M2tide before the dike construction are similar to the observed ones. Therefore, the amplitude and phase after construction at Geum River estuary dike increases compared to before construction at Geum River estuary dike. The scour occurred in the A-A' section.

• 한국해안·해양공학회논문집
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• 제21권6호
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• pp.453-461
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• 2009

새만금 방조제 건설 이후 새로운 갯벌 생성이 보고되고 있는 1호 방조제 앞 대항리 갯벌의 지형 변화에 대한 영상 관측을 수행하였다. 갯벌 지역은 이동상의 어려움과 밀/썰물에 따른 시간상의 제약으로 국지 혹은 소수 기선의 현장 관측만으로 제한되는 경우가 많다. 본 연구에서는 밀물시 조간대 갯벌에서 이동하는 수륙 경계선은 간조와 만조 정선 사이의 등고선을 나타낸다는 자연적인 원리를 이용하여 연속 촬영된 영상에서 관측된 수륙 경계선에 대한 실제 공간 좌표를 계산하고 이를 모두 통합함으로서 조간대 지형에 대한 3차원 지형정보를 획득하였다. 2005년 9월부터 2009년 9월까지 6차례의 영상 관측 결과를 분석한 결과 1호 방조제 외측 갯벌은 매년 평균 0.127 m 씩 퇴적된 것으로 나타났으며 공간적 및 시간적으로 다양한 변화를 보였다.