• 한국해양공학회지
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• 제6권2호
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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.

• 한국해양공학회지
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• 제7권1호
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• pp.156-161
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• 1993

Structures built in the coastal area often cause unexpectedly severe shoreline change on the adjacent beaches. Therefore, beach evolution is one of the most important problem in the coastal engineering. Beach evolution in the coastal area consisted of wave transform model and sediment transport model. Ebersoale's elliptic mild slope equation which considered the effect of combind wave refraction and perline and Dean's one line theory for the sediment transport model were used in this study. Kwangan beach was selected as study area and field observations were done. Numerical simulation for beach evolution in the Kwangan beach was performed and shoreline change predictions were suggested as results.

• International Journal of Naval Architecture and Ocean Engineering
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• 제2권2호
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• pp.68-74
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• 2010

The development of a numerical model using the fractional area/volume obstacle representation (FAVOR) method for predicting a nearshore current field bounded by complicated geometric shapes, and a three-dimensional (3D) beach evolution was described in this article. The 3D model was first tested against three cases to simulate the nearshore current fields around coastal structures, a river mouth, and a large scale cusp bathymetry. Then, the morphodynamic model tests, which are adopting the nearshore current model, were applied for the computations of beach evolution around a detached breakwater and two groins. It was confirmed that the presented model associated with the FAVOR method was useful to predict the nearshore current field in the vicinity of the complicated geometric shapes. Finally, the model was applied to a tombolo formation in a field site of Kunnui fishery port, which is located in Hokkaido, Japan.

• 한국환경과학회지
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• 제15권9호
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• pp.881-886
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• 2006

The purpose of this research is to examine the beach erosion prevention capability of submerged breakwaters under wave energy condition. To accomplish this objective, the computational domain was divided into two do-mains : the large and the detailed domain for the Song-Do beach. For each computational domain, numerical models for calculating transformation, wave induced current and beach erosion were used and also these numerical models were carefully applied to three experimental cases such as 1) the present beach condition, 2) the condition for which submerged breakwaters are installed about 240m from the shoreline of beach enlarged by artificial nourishments. The results of this research show that if storm waves attack the present beach, the erosion occurs widely all over the beach. However, when the submerged breakwaters are installed in addition to the artificial nourishments, storm waves can be adequately controlled and strong wave induced currents occur only around the submerged breakwaters resulting in the beach evolution appearing locally only at the western end of the beach.

• 대한토목학회논문집
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• 제11권1호
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• pp.177-188
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• 1991

해빈변형(海濱變形)은 주로 파랑(波浪)과 흐름의 작용을 받아 표사이동(漂砂移動)에 의하여 생긴다. 본 연구(硏究)는 표사이동이 주로 발생되는 천수역(淺水域)에서 해빈변형을 예측(豫測)할 수 있는 3차원(次元) 해빈변형(海濱變形) 수식모형(數式模型)을 개발(開發)하였다. 파랑변형(波浪變形)은 흐름과 파랑이 공존(共存)하는 경우의 모형을 개발하였고 흐름조건은 이안류(離岸流)가 존재하는 경우를 상정(想定)하였으며, 표사량(漂砂量) 산정식(算定式)은 Flux모형(模型)을 사용하였다. 본(本) 연구(硏究)의 모형을 일정(一定) 구배를 가진 해빈(海濱)에 적용해 본 바, Watanabe의 수치해석 결과와 정성적(定性的)으로 유사한 결과를 얻었으며, 해안구조물(海岸構造物)이 있는 경우에 해빈류(海濱流)의 계산이 가능한 해역(海域)에서는 본(本) 모형(模型)의 적용이 가능할 것으로 판단된다. 매개변수(媒介變數)들이 해빈변형에 미치는 영향은 입사파고(入射波高)가 클 때, 흐름이 강할 때, 저질입경(低質粒徑)이 작을 때, 해저(海低) 구배가 클 때 큰 것으로 나타났다.

• 물과 미래
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• 제21권3호
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• pp.299-307
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• 1988

돌제 주위의장기간 해빈변형을 예측하기 위하여 수위의 변동, 파의굴절과 회절을 고려하여 해석하는 수치적 모델이다. 이러한 문제에 대한 수치해석은 연안표사랑에 대한 경계조건을 가지는 방정식을 고려함으로써 해석된다. 해석방법으로는 음해법 중의 하나인 Crank-Nicolson Scheme을 사용하였다. 이 모델을 현지에 적용시킨 결과, 굴절과 회절계수의 근사해로 인하여 돌제 내부 영역에서는 실측치와 예측치가 차이가 있으나, 돌제 외부 영역에서의 경향은 잘 일치하고 있음을 알 수 있다.

• 한국해양공학회지
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• 제32권5호
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• pp.351-360
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• 2018

The construction of large scale harbor structures at Maengbang beach, which is located on the eastern coast of Korea, is of great concern because it may cause disastrous beach erosion in the vicinity. Therefore, a hydraulic model experiment was conducted to examine the morphological changes after such construction. The water depth was scaled using the method of Van Rijn (2010), which is a well-known scale law, but the results appeared to be overestimated. The present study developed a new scale law that applies an equilibrium beach profile formula to scale the model evolution to the prototype scale. When compared with survey data observed at Maengbang beach, the proposed method showed better agreement than the method of Van Rijn (2010).

• 한국해양공학회지
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• 제22권2호
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• pp.28-33
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• 2008

From the 1997 to January, 2004, a groin 156m long was constructed at the mouth of the Heoya river-mouth as a protection and barrier. To understand the changes to Jinha beach from the blockade of the river mouth, several aerial photographs, etc., were compared, which showed that the changes were significant. Comparing these results to the state of the area before construction of the groin, the blockade of the river was relaxed, but the formation of the tombolo, in the middle groin area was accelerated and the total Jinha beach erosion and especially the erosion of the southern part of Jinha beach was developed. But according to statements by residents and some current documents, the blockade of the Heoya-river mouth is still underway at the surrounding areas of the groin and chronic dredged sand has been used for littoral nourishment at the northern part of the middle groin and on Jinha beach. The result of numerical simulation based on the present state shows that if this sort of dredging is stopped, the sand accumulation will progress near the river mouth groin and the existing tombolo at the middle groin will progress to the north and severe erosion will occur at the southern coastline near the middle groin and the farthest southern part of Jinha beach, and Jinha beach itself will experience a gradual erosion. The main reason for these erosions should be the typhoons that are happening during the summer season. To provide protection from these kinds of undesirable erosions, a total of 23 numerical simulations have been done. It has been shown that submerged breakwaters at the front area of the beach will be efficient to protect from main beach erosion, but there should be alternative proposals for the influence of the river mouth blockade.

• 한국제4기학회지
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• 제12권1호
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• pp.1-8
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• 1998

동해안의 강원도 양양읍 남대천 하구에 발달한 spit beach의 지형적변화(1979∼ 1996) 는 outlet의 위치변화와 해안선 모습의 변화로 규명되었는바 일차적인 변화는 해안에 평행한 spit의 성장이며 이차적인 변화는 spit폭의 변화(overwash across sedimentation)라 고 밝혀졌다. 해빈환경의 소환경(subenvironment)으로서 swash zone과 berm crest는 각각 의 특징적 퇴적상(조직매개변수)으로 구분되는바 이에 관한 분석결과가 기술되었다.

• 물과 미래
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• 제11권1호
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• pp.39-46
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• 1978

The approaching deep water wave heights and directions affect the wave energy which is carried to the coast. By studing the relations between the longshore wave energy theory and the evolution of coastline, writer can arrive following conclusion. The longshore lottoral drifting affects to a great deal the formation of the coast, and by investigating on the eastern coastal geomophorogy of korea, the theory was proued as a true and made it possible to an approaching to the subdivided classification of eastern coast of lorea. That is to asy that angle taken by the level between the wave crest line of prevailing wave(NE) and the coastline was measured as less than 15#, and in the area neighboring the river which served as source of Sand parrticles, there are grand scale formation of sand beach expectable, in the other hand the formation of sand beach in case of $35^{\circ}{\leq}{\alpha }o{\leq}55^{\circ}$ which represents the vivid phenomena of longshore littoral drifting was proved not influencial but rather transformed into a rocky coast. Depending on the above facts the writer classified general shape of the coast affected by the vivid wave action into the following three, (1) The equilibrium beach. (2) Erosinal beach. (3) Geomophorogical beach, and made the sandy and rocky coast are subdivided as S-A.B.C. and R-DEF.