• Journal of the Korean Society of Hazard Mitigation
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• v.3 no.2 s.9
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• pp.139-145
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• 2003

This study is to propose reduction effect of scour depth and a optimum size of circular collar through experimental analyses with various collar sizes. To do so, we carried out hydraulic model experiments. In the case of with considering the collar, the effect of reduction of scour depth increased according to the increase of collar size. When size of collar is 2 as the ratio of collar diameter(W) to pier diameter(D), scour depth is decreased about 67% and deposition height is increased about 70%. The optimal size of collar proposed in this study is W/D=2 by analyzing reduction effect of scour depth, size of scour hole, and deposition height.

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 1997.10a
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• pp.81-85
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• 1997

최근 연안해운시스템구축을 목적으로 대형신항만 건설계획이 추진되고 있으며, 교통수송 등의 편리성 및 경제성을 확보하기 위한 다수의 해상교량이 건설, 설계되고 있다. 이처럼 해안역에 구조물이 축조되면 파랑과 조류 및 연안류의 작용에 의하여 구조물 주위지반에는 세굴현상이 발생하는 것이 일반적이다. 이와 같은 세굴현상은 구조물의 안전성에 매우 심각한 영향을 초래하는 경우가 많다. 그러므로 해상구조물 건설시에는 세굴현상에 대한 세밀한 검토를 실시하여 대책을 강구하여야 할 필요가 있다. (중략)

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 1998.09a
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• pp.51-55
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• 1998

서해대교가 건설중인 아산만은 세계적으로 조수간만의 차가 크기로 유명한 곳이며 해저지반 또한 실트질이나 풍화토로 이루어져 세굴에 취약한 지형이다. 더욱이 아산만의 개발 및 공사중 축조된 축도로 인한 통수단면적의 감소로 실제 유속이 2.7㎧에 이르고 있다. 이러한 유속의 증가는 조석의 왕복운동과 함께 교량세굴을 촉진하였고 교량의 안전을 위해 세굴의 추이를 면밀히 검토할 필요가 대두되었다. (중략)

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 1998.09a
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• pp.61-64
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• 1998

서해안시대의 개막과 함께 서해안 일대의 개발이 활발해지면서 서해대교, 영종대교 같은 대규모 해상교량의 건설이 이루어지게 되었다. 이들 구조물의 건설로 인해 흐름이 변하고 유속이 증가하면서 구조물의 안전에 심각한 영향을 미칠 세굴이 관심사로 떠올랐다. 하지만 해상세굴에 대해 연구된 기존의 자료가 거의 전무한 실정이므로 현장에서 직접 세굴의 진행과정을 관찰하는 것이 절대적으로 필요하다. (중략)

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 1998.09a
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• pp.56-60
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• 1998

하천 및 해상에서의 구조물 건설시 세굴에 대한 영향으로부터의 구조물 안정성 확보는 구조물의 설계 및 시공상 중요한 검토 항목 중 하나이다 따라서, 과거부터 이와 같은 구조물 주변의 세굴문제를 해명하고자 하는 연구가 계속 되어져 왔다. 특히 교각 주변의 국소세굴에 대한 현상의 해명 및 방지대책의 개발은 더욱더 중요한 과제 중의 하나로서 인식되어지고 있다. (중략)

• Ecology and Resilient Infrastructure
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• v.7 no.2
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• pp.83-89
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• 2020

This hydraulic study analyzed the scour effect at fixed downstream weirs based on the changes in the upstream bed slope. The study was performed using six different bed slopes, that is, 0%, 2%, 3%, 4%, 7%, and 10% at 0.117 ㎥/s in all cases. The scour depth, scour length, and scour volume were measured using a broadband laser scanner to quantitatively analyze the scour at the downstream weir. This study also examined the adequacy of the designed apron length by comparatively analyzing the results of the scour experiments and the apron length calculated using conventional design standard formulas. The analysis of the local scour effect at the downstream weir showed that scour length and scour depth increased as the bed slope became steeper. A comparison between the results of the scour experiment and that of the conventional design formulas showed that both formulas of the National Construction Research Institute and the Bligh were distributed within the allowable values when there was no upstream bed slope. However, as the bed slope upstream of the weir gradually increased, the scour lengths of the apron deviated slightly from the values obtained from the conventional design formulas.

• Journal of the Korean GEO-environmental Society
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• v.14 no.5
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• pp.15-22
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• 2013

The submarine pipe, which is one of the most important coastal structures, is widely used in the development of coastal and ocean engineering. The scour of the submarine pipe occurs due to the wave and the current according to the state of the sea bed. The scour affects the submarine pipe and causes it to undergo settlement and fatigue. It is difficult to predict the local scour under complicated and various conditions of the coastal environment, even though many researches on the scour of the submarine pipe have been studied in recent years. This study analyzed the scour depth around a submarine pipe by using the Neural Network technique. The back-propagation algorithms was used to train the Neural Network. The 58 simulating experimental data for the performance and validation of the Neural Network technique were analyzed in this study. Then, the regression analysis for the same data was performed in this study to predict and compare with the Neural Network technique for the scour depth.

• Journal of Korea Water Resources Association
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• v.31 no.3
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• pp.269-277
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• 1998

Laboratory flume experiments to investigate the characteristics of the flows and local scour around circular bridge pier in a curved channel are performed. In this study, the effect of a circular collar device for controlling the depth of scour is examined. The scour depth with a collar is about 40% of the scour depth without collar in the straight course of the flume while it is about 44% of the scour depth without collar at the location of 150' in the curved channel. As the results of experiments using the collar of which diameter is twice of pier, the reduction of scour depth is the most effective in a straight channel when the location of collar is 0.2h( h:depth) below the channel bottom. And, the reduction of scour depth is the most effective in a curved channel when the location of collar is 0.1h below the channel bottom.

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 2004.08a
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• pp.356-360
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• 2004

• Journal of Korea Water Resources Association
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• v.39 no.7 s.168
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• pp.583-592
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• 2006

There has been debated on the fact that a scour hole produced by the construction of a groyne has environmental benefits such as provision of diverse underwater habitats and shelter for fish in the event of flooding. Therefore researches are focusing on the scour field around the groyne area beyond the existing safety issues. The scour area on aquatic habitats would format many form on groyne conditions so that the analysis of scour area is strongly required. This study conducted the experiments on permeability and installation angle of groyne and suggested the data for groyne selection in environmental point as analyzing scour area. The physical modeling was performed in different permeability (0%, 20%, 40%, 60%, 80%) and installation angle of groyne ($60^{\circ},\;90^{\circ},\;120^{\circ}$). As the result of the study, scour area and scour depth at maximum scour condition was revealed for each case and suggested the differences according to experiment conditions.