• Geomechanics and Engineering
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• 제33권4호
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• pp.415-425
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• 2023

Pile-supported wharves, port structures that support the upper deck, are installed on sloping ground. The sloping ground should be covered with a rubble mound or artificial blocks to protect the interior material from erosion caused by wave force. The behavior of the pile may vary during an earthquake if a rubble mound is installed on the slope. However, studies evaluating the effect of rubble mound on the pile during an earthquake are limited. Here, we performed dynamic centrifuge model tests to evaluate the dynamic behavior of piles installed in a slope reinforced with rubble mound. In the structure, some sections (single-pile, 2×2 group-pile) were selected for the experiment. The moment of the group-pile decreased by up to 26% upon installation of the rubble mound, whereas the moment of the single-pile increased by up to 41%, thus demonstrating conflicting results.

• 한국해양공학회지
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• 제16권3호
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• pp.40-45
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• 2002

In this study, the effects on hydraulic characteristics are discussed as the permeable underlayer thickness of the rubble mound structure changes. A series of hydraulic experiments were performed and wave run-up, reflection and set-up were investigated. Result indicated that wave run-down was affected by the water out from the permeable underlayer during down-rush. As the thickness increased, relative wave run-up decreased.

• 대한토목학회논문집
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• 제40권5호
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• pp.497-507
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• 2020

Tetrapod로 피복된 경사형 수중구조물을 대상으로 파랑의 전파현상을 검토하기 위해 2차원 수리실험을 수행하였다. 수리실험은 수중구조물의 서로 다른 상대여유수심, 상대여유고, 상대상단폭 및 파형경사 등을 적용하여 수행되었다. 수리실험결과를 이용하여 경사형(부분투과형) 수중구조물에 대한 파고전달계수 산정식을 제안하였다. 제안된 경험식은 경사형 수중구조물의 파고전달계수를 충분한 정도로 예측함을 확인하였으며, 기존 경험식을 개선하였다.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2004년도 학술대회지
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• pp.303-308
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• 2004

The failure at the head section of rubble mound breakwaters is more important than other failure modes. because this initial failures will occur the failure of the trunk section and lead to the instability of the structure. The three-dimensional failure modes are discussed using the experimental data with multi-directional waves considering the failure modes. It was occurred by the topographical characteristics around the head of rubble mound breakwater. The spacial characteristics of failure mode around the rubble-mound structures can be summarized as follows: 1) It was clarified that the failure modes at the round head of a detached breakwater are classified as failure by plunging breaker on the slope, failure by direct incident wave force and failure at the rubble mound breakwaters. 2) The failure mode was found in the lower wave height than the design wave by the breaker depth effects and topography around structures. It is clarified that the structure was monitored safely designed for the design wave but the failure was occurred by the reason of breaker waves.

• 한국해양공학회지
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• 제27권6호
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• pp.90-94
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• 2013

This paper reports the results obtained for there flection and transmission coefficients on rubble mound breakwaters in Busan Yacht Harbor. A2D physical model test was conducted in the wave flume at the Coastal Engineering Research Laboratory at Pusan National University, Busan, South Korea. In this study, physical model tests were completed to further our understanding of the hydrodynamic processes that surround a rubble mound structure subjected to irregular waves. In particular, the reflection and transmission coefficients, as well as the spectrum transformation, were analyzed. This analysis suggests that with an increase in wave height around a rubble mound, the reflection coefficient drastically increases at each water level (HHW or MSL or LLW). Moreover, when the water level changes from HHW to LLW, the reflection coefficient is suddenly reduced. A further result of the analysis is that the transmission coefficient strongly drops away from the rear of the structure. Finally, in regard to the rubble mound breakwater in Busan Yacht Harbor, a consideration of the reflection and transmission coefficients plays an important role in the design.

• 한국해양공학회지
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• 제16권4호
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• pp.7-12
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• 2002

This study is aimed to find the scouring mechanism at the toe of rubble mound structures. To investigate the characteristics of scouring in front of the structure, experiments were performed with regular waves in a 2-D flume. The results of this study are as follows. 1) It can be said the characteristics of incident wave causes rolling and sliding of armour block. The difference of wave pressure on the slope, internal flow as well as settlement of armour block due to the weight cause scouring. 2) It is observed that scouring depth at the toe increased when wave height or period increased. The location of ultimate scouring and deposition depth moved seaward when wave period increased. 3) The failure of rubble mound structure was caused by waves or scouring. Failure by erosion increased with high waves and long waves. 4) Using surf-similarity parameter including characteristics of incident waves and structure, scouring and deposition pattern were found and their limit was formulated.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2004년도 학술대회지
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• pp.120-126
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• 2004

The failure modes analysis by the real process method at the head section of rubble mound breakwaters is more important than other failure modes analysis. because this initial failure modes and failure process will lead to the destruction of the structure. The three-dimensional failure modes are discussed using the experimental data with directional waves considering the failure modes. It was processed step by step failure around the head of rubble mound breakwaters. The spacial characteristics of failure mode by real process analysis was well descript at the rubble mound structures.

• 한국방재학회:학술대회논문집
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• 한국방재학회 2008년도 정기총회 및 학술발표대회
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• pp.443-445
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• 2008

Determination of allowable overtopping rate for coastal structure is a key point to determine the application of background of coastal structure while considering safety and economic efficiency. Thus, the accurate estimation of overtopping rate against coastal structure is essential. In general, estimation of overtopping against the coastal structure is based on an empirical formula or hydraulic experiment. In this study, we investigate the behavior of overtopping for rubble mound coastal structure with rubble armor stone and wave dissipating block using hydraulics experiment, and domestic or foreign design standard.

• 한국해양공학회지
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• 제24권1호
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• pp.90-98
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• 2010

In this paper, vibration-based structural health monitoring methods that are suitable for caisson-type structures are examined by an experimental evaluation. To achieve the objective, four approaches are implemented. First, vibration-based structural health monitoring methods are selected to monitor the structural condition of caisson-type breakwaters. Second, a lab-scaled caisson structure is constructed to verify the selected monitoring methods. Third, the vibration characteristics are numerically analyzed using an FE model due to the change in the rubble mound condition. Finally, experimental vibration tests of the lab-scaled caisson structure are performed to monitor the vibration responses due to changes in rubble mound conditions and the performances of the selected methods are examined from the monitoring results.

• 대한토목학회논문집
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• 제35권4호
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• pp.845-852
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• 2015

파랑의 처오름높이는 항만 및 호안구조물의 마루높이 산정에 있어 주요한 설계요소이다. 본 연구에서는 TTP로 피복된 경사식구조물을 대상으로 2차원 수리실험을 수행하였으며, 실험에 적용된 실험파는 불규칙파로서 구조물 toe 위치에서 비쇄파, 쇄파 및 쇄파된 파의 조건을 포함한다. 본 실험결과를 이용하여 사면경사 1:1.5인 경사식구조물의 처오름높이를 산정할 수 있는 경험식을 쇄파 유사성 매개변수를 이용하여 제안하였다. 그리고 본 실험결과는 기존 연구결과인 van der Meer and Stam(1992)의 결과와 비교하였다.