• Journal of Ocean Engineering and Technology
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• v.14 no.3
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• pp.55-60
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• 2000

This paper is descried the experimental results of beach process including storm surge and beach recovery. By testing different surge levels and durations, effects of these to shoreline change were evaluated. In addition of beach recovery were investigated experimentally. On the other hand, we proposed the method, which can be applicable to complex hydrograph such as storm surge by modifying equation proposed by Kriebel and Dean. Moreover, applicability of this method is verified by comparing computing result with experiments.

• Journal of the Korean earth science society
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• v.28 no.7
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• pp.914-924
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• 2007

This study is to compare differences in the depositional environments of natural beaches with those of beaches developed with artificial structures in the East Coast of Korea. Naksan-Osan beaches were selected for the examination of natural beaches and Anmok-Yumjun beaches for that of developed beaches. The study was performed on the foreshores and backshores of the selected beaches, and was based on the field research during the flood period of year 2004 and the dry period of year 2005. In Naksan-Osan beaches, pain size is fuel and sorting is better from northern coast to southern coast. Furthermore, sediment undergoes changes regularly and seasonal variations are small. But in Anmok-Yumjun beaches, grain size is coarser and sorting is worse than in Naksan-Osan beaches, showing irregular tendencies. The characteristic features of the two beaches would be effected by longshore currents which change along the type of coast line and have an effect on sediment. Especially, long shore currents interrupted by artificial structures in Anmok-Yumjun beaches may cause sedimental environment changes. In Anmok-Yumjun beaches, harbor expansions will be continued, and thus more changes are expected to occur in the beaches.

• Journal of the Korean earth science society
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• v.24 no.6
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• pp.568-577
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• 2003

The purpose of this paper is to examine the geomorphic processes of beach and sanddune development in the Chungcheong-Namdo Province. The sands consist mainly of quartz and feldspar with lesser amounts of mica and other heavy minerals. With the exception of those from the granite, the sands have a very fine texture. Another characteristic of the sand grains is low degrees of roundness and grading indicating that source areas for the material were in the vicinity of the accumulating field. Over the years, the beaches have receded as a response to the decreasing amount of depositional materials. The driving force for the formation and transformation of coastal dunes in the study area is dominant winds from the center of the Siberian High. To some extent, the erosion of coastal dunes has been a global phenomenon. The degradation process occurred most actively when spring tides attacked beaches, berms, and foredunes. The relief and shape of present-day coastal dunes is determined initially by the Pleistocene strata underneath. From the fact that the strata contained traces of frozen structure, it can be inferred that sediment once experienced the process of soil formation.

• 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).

• Journal of The Geomorphological Association of Korea
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• v.18 no.4
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• pp.283-296
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• 2011

The aim of this study is to analyze the short-term changes of beach and dune morphology at Hwajin beach, Korea using by terrestrial LIDAR. Based on ArcInfo as point cloud obtained through precise analyzing studying area twice (1st : Sep 1. 2010, 2nd : Oct 2nd. 2010) by terrestrial LIDAR, alteration of beach and dune was analyzed at DEM, of which cell size is about 10cm. Consequently, during the studying period, coastlines at studying area moved backward and reduced the area of coastal zone. In a section change, the north beach moved backward with more eroded beach face and the middle section of south beach moved forward with more deposited beach face. Considering all the section changes of beach at studying area, beach section during the 1st measurement period can be defined as a summer profile, and it can be explained that the temporary storm profile was formed by the strong wave created during studying period. As a result of analyzing the alteration of beach area by terrestrial LIDAR, alteration of narrow area was able to be analyzed in detail by class of 'centimeter' and the time was able to be shortened.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2018.11a
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• pp.40-42
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• 2018

지구온난화에 따른 연안의 해수면 상승은 해안에 가해지는 파랑에너지의 상승을 유발한다. 이러한 해수면의 상승은 상대적으로 수심이 깊어지는 효과를 초래하고 이는 과거 발생하지 않았던 해안지역의 침식 및 해빈에서의 모래를 유실시킨다. 특히, 국내 연안 225개소의 연안 모니터링 결과 142개소인 62%가 침식우려 이상의 등급으로 나타났다. 일반적으로 연안침식에 대응하는 방법은 호안을 쌓아 보호하게 되는 경성공법으로 외력의 변화에 따라 현장여건에 맞는 호안의 경사, 단면형상 및 재료를 선택하게 된다. 하지만 현상에 대한 불충분한 이해에 근거한 공법 적용으로 제반국가에서 다양한 피해가 발생하고 있으며, 이는 공법신뢰도 향상을 위한 기술개발 및 융합기술 도입의 필요성을 보여준다. 본 연구는 파랑저감에 효과적인 다공성 구조물Biocoast를 활용하여 해안침식피해억제를 위한 친환경 투수 바이오 콘크리트 블록을 개발하였다. 특히, 자연해변 및 호안시설에 대해 자연 및 인위적 외력에 의한 침식과 세굴로부터 연안을 보호하고, 블록의 유닛화를 통해 품질관리 및 공정관리의 효율성을 향상시킬 수 있을 것으로 사료된다.

• Journal of Korea Water Resources Association
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• v.39 no.1 s.162
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• pp.69-77
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• 2006

Songdo beach in Pohang City has suffered from bouts of beach erosion due to various reasons over many years. One of the most controversial issues is the extent of the harbor facilities effect on the beach erosion. In this study, the characteristics of erosion to Songdo beach were reanalysed using historical data and some aerial photos. Specifically, we set test cases based on the history of human modifications to the surrounding area and the topographic change around Songdo beach were investigated by 3D topographical deformation model. In the end, based on the results of these various kinds of investigation, this study found multiple causes of Songdo beach erosion.

• Journal of the Korean earth science society
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• v.34 no.2
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• pp.120-135
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• 2013

To investigate the changes in depositional environment around Gangneung Harbor, we analyzed the surface sediment textural parameters and topography data collected five times from February 2007 to February 2009. In the study area, sediments were mainly composed of sand and its sediment size became finer at offshore sites. During summer time, however, the sand grains became coarser than winter season near Namhangjin Beach, inside the harbor, and offshore areas. On the other hand, the grain size of Anmok Beach showed a gradual finer trend with time. Compared with the previous studies conducted before the completion of Gangneung Harbor construction, the mean grain size became finer on Anmok Beach, while it was coarser on Namhangjin Beach. The bathymetric changes observed over a 2-year period showed predominant erosion in the area of 5 to 10 m water depths and deposition in 2 to 5 m water depths. The shallower area less than 2 m water depths showed an alternating trend and yet slightly more dominant erosion process. The sediment textural parameters and the distribution of erosion and deposition have changed continuously. Results imply that such changes show long-term trends as well as seasonal variations in which the trend may have been formed after the completion of Gangneung Harbor construction.

• Journal of the Korean GEO-environmental Society
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• v.3 no.2
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• pp.71-79
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• 2002

A numerical simulation has been performed on the generation of the coastal cliff which lies as the distinct boundary between the beach and the hinterland. As a result of storm surge, it is known that the steeper the initial beach slope, the larger the generation of the coastal cliff. The rise of water level added the mean water level accelerates the generation of the coastal cliff. In addition, the longshore distribution of the incident wave height is one factor that bring about the generation of the non-uniform coastal cliff in longshore direction. Therefore this study will be able to use for expecting the formation and erosion of coastal cliff in sand beach.

• Korean Journal of Remote Sensing
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• v.33 no.6_1
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• pp.971-980
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• 2017

In this research, it was presented that the strategic approach for the long-term shoreline changes using historic digital aerial images can be effective for the analysis on the bangameori beach, west coast of South Korea. For this purpose, we collected several historic digital aerial images over 9 years in the research filed and conducted GPS-VRS surveying for GCP (Ground Control Point) acquisition. Also we collected existing two dimensional shoreline digital map which was published by KHOA (Korea Hydrographic and Oceanographic Agency) in the year 2013. With these multi data sets, we provided quantitative analysis on coastal erosion using the long-term shoreline changes in the beach. Also, As the results it was found that 2m sea level was retreated in the research period with maximum 0.31m length.