• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2014.10a
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• pp.9-11
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• 2014

As Daecheon beach, which is the study area, has problem of erosion and loss of most beach under the extraordinary wave during the typhoon event, it is necessary to apply erosion control measures for short term impact. Therefore, we analyzed the status and reason of the erosion by field survey, collection of hydraulic model test, and numerical model experiment. For the erosion control measure, we adopted beach feeding and submerged reef method available at that site among various counter measures. Numerical analyses were made for both beach feeding only and beach feeding with submerged reefs and these were compared with the present status to find out the optimum design and to contribute for preparing a long term plan of beach loss protection.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.14 no.4
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• pp.247-256
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• 2002

Most of fishing ports on the east coast of Korea have constructed around sand beach. Such fishing port structure had caused important effect in erosion of neighborhood sand beach. In order to solve the problems, we have to understand the mechanism through estimations and accurate reproduction beach erosion. Simulataneously, we have to devise a suitable countermeasure for beach erosion to the object coast. This study suggests economically substantial countermeasure for beach erosion around the fishing port and investigates, the preventive effects using a numerical simulation technique.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.20 no.6
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• pp.602-610
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• 2008

A beach has such functions as disaster prevention, providing an amenity place, attracting people and maintaining the coastal ecosystem. Already well known that a beach provides an amenity place, it has also been ascertained through various examples that a sand beach performs a very important function to maintain the coastal ecosystem as well. However, Beach erosion began to occur in Korea in the 1990's and posed a social problem in the late 1990's. Nowadays, along the shorelines of Korea's many beaches, about 400 beaches have reported erosion. This study demonstrate the Disaster Overall Prevention System for Beach Erosion and it's application. The Disaster Overall Prevention System for Beach Erosion is a coastal management system established for managing the implementation of long-term countermeasures to protect eroded beaches effectively in this study. Especially, the economic feasibility test and adaptive management for sustainable mitigation included in DOPS. The coastal prevention work applied to Namae beach is carried out by Disaster Overall Prevention System. Consequently, beach nourishment is proposed as a main countermeasure. Also, submerged artificial reefs and groin integrating artificial rock are proposed as secondary countermeasures for beach erosion. This resulted to be the optimal beach erosion countermeasure from DOPS, considering the economic and environmental conditions of the study area.

• Journal of Navigation and Port Research
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• v.29 no.6 s.102
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• pp.537-545
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• 2005

Traditionally Jeju island has a mild oceanic climate throughout the year and famous as worldwide resort area bemuse of its pure natural environment and dramatic coastal scenery. But unpredicted coastal erosion problem, mused by variation of environmental conditions from construction of coastal structure and renovation of the existing ports, has raised its head above the water, and is becoming serious these days just like other coastal area in Korea. The phenomena happen here along the seaside of southern part of the island show that severe changes in coastal line from erosion and even witnessed the coastal cliff failure. In advanced countries, coastal engineers and researchers have studied deeply about this kind of problem for a long time. However, as it is not sot active in Korea and lack of research data, there exists difficulties on building protection methods and thoughtless constructions might make it more complicated and fatal to the coastal environment. In this study, we investigated some case studies of other countries and intended to induce and propose some integral protection methods for coastline erosion, considering environmentally sound and water friendly way of development such as artificial reef, floating breakwater, and double cellblock breakwater. Finally, we made analysis on the proposed methods with numerical model test and evaluation on the feasibility of each method.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.29 no.1
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• pp.11-19
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• 2005

Traditionally Jeju island has a mild oceanic climate throughout the year and famous as worldwide resort area bacause of its pure natural environment and dramatic coastal scenery. But unpredicted coastal erosion problem, caused by variation of environmental conditions from construction of coastal structure and renovation of the existing ports, has raised its head above the water, and is becoming serious these days just like other coastal area in Korea. The phenomena happen here along the seaside of southern part of the island show that severe changes in coastal line from erosion and even witnessed the coastal cliff failure. In advanced countries, coastal engineers and researchers have studied deeply about this kind of problem for a long time. However, as it is not sot active in Korea and lack of research data, there exists difficulties on building protection methods and thoughtless constructions might make it more complicated and fatal to the coastal environment. In this study, we investigated some case studies of other countries and intended to induce and propose some integral protection methods for coastline erosion, considering environmentally sound and water friendly way of developement such as artificial reef, floating breakwater, and double cellblock breakwater. Finally, we made analysis on the proposed methods with numerical model test and evaluation on the feasibility of each method.

• Ecology and Resilient Infrastructure
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• v.6 no.4
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• pp.217-226
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• 2019

Optimum engineering methods for bank protection were classified based on steepness of bank slope and an existence of waterfront facility in the floodplain, and a new concept of eco-hybrid rolling mat method which could be applicable for the unfitted cases with previously developed countermeasures was suggested in this study. The eco-hybrid rolling mat method can be constructed while maintaining the river environment and ecosystem that does not interfere with the ground and slopes, when bank erosion occurs, it is an economical and efficient construction method that can protect the revetment and the bank slope immediately. The developed eco-hybrid rolling mat method was verified for the designed structure, system, function and effect based on large-scale river experiments including field exposure and decomposition test. As a result, the normal operation and effect of the rolling mat ted under low and high velocity conditions were confirmed with respect to bank protection. The effect of bank erosion prevention was quantitatively validated by sediment concentration monitoring and analysis, and the product specification of the eco-hybrid rolling mat was presented based on the standardized mat applied in real-scale tests.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.31 no.5
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• pp.305-313
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• 2019

Number of coastal protection structures have been increased rapidly due to rising sea levels and deteriorated sea conditions. Coastal structures should be designed to meet coastal engineering requirements and ecosystem conditions, while they are not lost or removed. In this study, trapezoidal gabion block was developed for the purpose, and two-dimensional laboratory experiments were conducted to validate applicability of the block. The experiments were carried out with eight types of erosive and accretive wave conditions. As a result, it was confirmed that the gabion blocks have a feature of preventing erosion of beach. The newly designed gabion blocks could be an alternative as a countermeasure method for beach erosion.

• Water for future
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• v.17 no.3
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• pp.197-209
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• 1984

This study has been carried out to investigate into the local scour of wall-toe and the beach deformation caused by the construction of a seal wall. It has been performed to determine the values of the marine invertigation of HAE UN DAE and two dimensional Movable bed gydraulic model test. From the results of this work approtection method of HAE UN DAE beach erosion is established to reduce the amount of topography deformation by investigating the values of the constructive position of a sea wall, seabed slope, the maximum scour depth, the first and the second influence range, the maximum quantity of beach deformation, and the distance measured from the sea will to the maximum quantity of beach deformation.

• Journal of Korea Water Resources Association
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• v.38 no.1
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• pp.59-71
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• 2005

Mountain watersheds are a lot of problems about soil erosion because of frequent wildfire occurrence. Runoff and soil erosion caused by the rain on a hillslope after wildfire are dependent on cover factor. And these has been a decrease by the cover factor recovery following time passage. The present paper defines the dynamic sensitivity of runoff and soil erosion that is the rate of runoff volume and soil erosion weight to rainfall energy and analyzes characteristics of the sensitivity for variation of cover factor, In according to the correlation analysis between other parameters and sensitivities, the sensitivity is the most dependent on the cover factor and the relation is exponential. The sensitivities after wildfire have suitable relation with treatment method for the mitigation of burnt forest and wildfire intensity. It was confirmed that the variation of soil erosion sensitivities come upon the range of stability in 5 years after wildfire.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.26 no.1
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• pp.1-8
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• 2014

In this study, a field monitoring on Namae beach erosion countermeasure in the east coast of Korea is conducted to verify its efficiency and effectiveness. The Namae Beach project has been carried out for six years with three years for planning and three years for actual construction. The planning phase of numerical model tests and investigations had been reported by Kim et al. (2008, 2011). The field monitoring confirms increase in the beach width after the submerged artificial reefs construction and is due to its wave energy dissipation effects. The field monitoring is performed at the seaward and landward of the countermeasures. The wave height reduction from the seaward side (depth h = 10.5 m) to the landward side (h = 3.7 m) of the reef is measured for wave transmission coefficient (Kt) analysis. The analysis shows 60% of deduction in wave energy due to the submerged artificial reefs.