• Journal of Korean Society of Coastal and Ocean Engineers
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• v.4 no.4
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• pp.243-249
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• 1992

Hydraulic experiments were carried out to investigate the hydraulic characteristics of solid and perforated-wall caissons of a mixed type breakwater for regular waves of various heights and periods. It was found that a perforated-wall caisson is more advantageous than a solid caisson for such hydraulic characteristics as reflection. transmission, and runup at the front face of the caissons and that the experimental results agree reasonably well with existing theoretical or empirical relationships. Especially the reflection coefficient of a perforated-wall caisson. mainly governed by the resonance in the wave chamber, was found to be minimum when the width of the wave chamber is approximately a quarter of the wave length in the wave chamber.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.5 no.2
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• pp.66-75
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• 1993

Hydraulic experiments were performed in order to gain an insight into the quantitative differences between the perforated wall caisson and its solid wall counterpart in the local pressure distribution and caisson stability. The results showed that the wave forces acting on local walls were smaller in the perforated wall caisson than in the solid wall caisson. For the caisson stability, the critical weights of the perforated wall caisson also turned out to be smaller than those of the solid wall caisson. The Phenomenon was attributed to the dual effects inherent to the perforated wall caisson, which are the decrease of total horizontal force and the phase difference between the total horizontal and vertical forces.

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 1992.08a
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• pp.130-134
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• 1992

본 연구의 목표는 혼성방파제의 무공 및 유공 케이슨에 작용하는 파압분포에 대한 기존의 연구결과를 조사, 분석, 정리하고 실제로 이들에 대한 수리모형실험을 실시하여 관측된 결과를 기존의 연구결과(곡본승리 등 1982, 고교중웅 등 1983, Goda 1985, Takahashi 1991)와 비교, 분석함으로써 케이슨에 작용하는 파압은 물론 기타 수리현상의 특성을 파악하는 데 있다.(중략)

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.31 no.6
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• pp.351-355
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• 2019

Load resistance factors for the limit state design of vertical caisson breakwaters are presented. Reliability analysis of 16 breakwaters in nationwide ports was conducted to calculate the partial safety factors and they were converted into load and resistance factors. The final load resistance factor was calibrated by applying the optimization technique to the individually calculated load resistance factors. Finally, the breakwater was redesigned using the optimal load resistance factor and verified whether the target level was met. The load resistance factor according to the change of the target reliability level is presented to facilitate the limit state design of breakwater.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.31 no.6
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• pp.344-350
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• 2019

In this study, waves2Foam implemented in OpenFOAM is used to simulate numerically the wave pressure on a verical caisson under the condition of with and without the placement of Tetrapods in front of the caisson. The comparisons of the numerical results and the experimental data show fairly good agreement between them. Based on this, it is possible to suggest an optimal combination of coefficients for an empirical formula to represent the protective TTP layer as porous media.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.33 no.6
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• pp.287-292
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• 2021

Load and resistance factor design is an efficient design approach that provides a system of consistent design solutions. This study aims to determine the load and resistance factors needed for the design of breakwater foundations within a probabilistic framework. In the study, four typical types of Korean breakwaters, namely, rubble mound breakwaters, vertical composite caisson breakwaters, perforated caisson breakwaters, and horizontal composite breakwaters, are investigated. The bearing capacity of breakwater foundations under wave loading conditions is thoroughly examined. Two levels of the target reliability index (RI) of 2.5 and 3.0 are selected to implement the load and resistance factors calibration using Monte Carlo simulations with 100,000 cycles. The normalized resistance factors are found to be lower for the higher target RI as expected. Their ranges are from 0.668 to 0.687 for the target RI of 2.5 and from 0.576 to 0.634 for the target RI of 3.0.