• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 1995.10a
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• pp.39-43
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• 1995

본 연구에서는 퇴적물 이동에 의한 해빈단면 및 해안선의 변화 형태를 파랑모델이나 순환모델의 도움없이 예측하는 간단한 수치 모델을 제시하는 데 그 목적이 있다. 해안선의 변형에 대한 연구는 그동안 많은 진척되었으며 최근 해빈단면의 변형 모델은 물론 3차원적인 복잡한 해저면에도 적응할 수 있는 복합적인 토사이동 모델이 활발히 개발되고 있다(Watanabe 등, 1980； Wang and Miao, 1992； 과학기술처, 1992). (중략)

• Journal of the Korean Society for Marine Environment & Energy
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• v.7 no.4
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• pp.199-206
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• 2004

Construction of a large offshore structure in coastal area may cause serious morphological changes for a wide region ranging from shoreline to offshore behind the structure. Shin et at. [2000] and Shin and Hong [2004] identified the sediment transport patterns behind the large offshore structure through a series of three dimensional movable bed experiments. In present study, a hybrid three dimensional beach deformation model was suggested based on those sediment transport mechanisms revealed by experimental results of the preceding studies. The model was verified by the results of the three dimensional moveable bed experiments and they agreed well not only in reappeared tombolo in shoreline side but also in the erosion and deposition region behind offshore structure. In addition, the model was applied to real beach deformation problem, which was occurred by construction of artificial offshore islands, and it validates the applicability of the model.

• Water for future
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• v.20 no.1
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• pp.4-13
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• 1987

• Journal of the Korean Society for Marine Environment & Energy
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• v.7 no.4
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• pp.207-215
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• 2004

Recently, securing a vast land in the land region becomes more difficult and efforts to seek its alternation in the sea area have been increased. As a consequence, the coastal region has been faced to extensive beach erosion problems. In planning offshore structures such as artificial islands, it is necessary to forecast the influence of the structure construction exerting on the beach erosion of the adjacent coast. In the present study, the sediment movement pattern behind offshore structure was examined through a series of three dimensional movable bed experiments, so as to develop the numerical model which forecasts morphological change including beach erosions. The experimental results reveal that the sediment movement patterns of the beach line side and the depth region are separated at a certain boundary line. In details, at the beach side including swash zone the sediment movement becomes dominant, which is governed by a relation between depth contours and incident wave directions, while at the depth region the bed load and suspended load due to the orbit motion of waves are carried by nearshore currents, and both movements are clearly separated at a specified boundary that is related to partial standing wave from the beach. It is expected that these results can be effectively used for verification of a numerical model on morphological change of the coast.

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 1993.07a
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• pp.42-44
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• 1993

최근, 불규칙파를 조파시킴으로서 발생하는 실험실 스케일의 해빈변형에 대해서 그 정선변화 뿐만아니라 수심변화까지 포함한 수치 simulation모델이 개발되었다. 그러나 현지파랑은 파고, 주기가 불규칙하고, 또한 입사파향도 일정하지 않기때문에, 앞서 논한 예측법에 의해 현지연안에서 발생하는 지형변동을 예측하기 위해서는, 현지파랑중 어떠한 방법으로 대표파고를 선정할 것인가가 큰 문제가 된다. (중략)

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.20 no.1
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• pp.101-109
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• 2008

Several numerical models for predicting beach profile changes have been developed by many researchers. Many of the earlier models are known to simulate the erosional profiles with the formation of offshore bar. However, most of the models don't have proper mechanism to incorporate the recovery process of the eroded profiles after a storm and can not simulate the beach accretion with acceptable accuracy. In order to overcome these shortcomings, we propose a new numerical model which has new features to simulate the accretional phase of beach recovery process after storm including such as redistribution of suspended sand particles near the breaking point. The simulation results of the proposed model were compared with LWT (Large Wave Tank) experiments performed at CRIEPI (Central Research Institute of Electric Power Industry in Japan) and CE (the Us Army Corps of Engineers) and it was shown to have performed better compared to SBEACH (Storm-induced BEAch CHange).

• Water for future
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• v.21 no.3
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• pp.299-307
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• 1988

A model is developed to predict the long-term beach evolution near the long groin considering the combined effects of variation of sea level, wave refraction and diffraction. A numerical solution for this problem is solved by considering the equation as a system subject to the boundary condition for longshore transport rate. One possible method is the centered Crank-Nicolson type implicit scheme. The results which ard obtained by applying this numerical model at Songdo beach, Pohang are as follows. Owing to the approximation used in the calculation of the refraction and diffraction coefficients, the discrepancy between the predicted and actual shoreline occurs to the interior of long groin. However, the shape of shoreline at the exterier of long groins agrees well.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.16 no.2
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• pp.75-82
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• 2004

The changes of sea bottom configuration, which may cause the coastal disasters, have been considered as social problems. It is obvious that the beach deformation is attributable to the sediment transport associated with erosion and acceration. The prediction method and countermeasures for them, however, are not on the level of satisfaction, which indicates that efforts should be made on developing them. In this study, it is found at the groin constructed in Sangju beach on e purpose of beach protection did the aversive function. The reason for this was judged that they accelerated the speed of erosion by increasing the velocity wave-induced current rather than brought storage effect of sediment. Authors found that the storage sediment estimation model by Sonu and Beek(1971) is a useful model at the Sangju beach with the use of topographical survey data from July, 1987 to March, 2003.

• Journal of Ocean Engineering and Technology
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• v.6 no.2
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• pp.133-142
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• 1992

Beach evolution is of the most important problem is the coastal engineering. Especially, the structure construction through reclamation in the shallow water region nesar the beach will cause many severe problems around the structure. Beach evolution due to the construction of an artificial island in this study was studied using wave transform model and associated of an artificial island in this study was studied using wave transform model and associated sediment transport model. Numerical simulation of the model was applied to the Kwangan beach using the data of waves and shoreline of the area. The combined wave transform model and beach evolution model showed good results. The results show a breakwater will be needed to prevent severe erosion near the eastward Kwangan beach when construction an artificial island in the Suyong Bay. Good results of the study also suggest that the present model can be more widely applied to the prediction of beach evolution.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.26 no.2
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• pp.96-102
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• 2014

A three-dimensional beach evolution model was presented to predict morphodynamics around a river mouth. The presented model was based on the depth-averaged (2DH) and quasi three-dimensional (Q-3D) nearshore current modules, and the model took into account shoreline changes, the effect of advection diffusion of suspended load and discharged sediments from the river. First, the 3D beach evolution model was applied to the formation of sand spits and terrace at the river mouth in order to investigate the performance of the model. Secondly, the model was applied to the river mouth at the Ara River, facing the Sea of Japan. The formation of sand spit at the Ara River in winter season was reproduced. The computed result showed qualitatively agreement with field site observation.