• Proceedings of the Korea Water Resources Association Conference
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• 2005.05b
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• pp.1078-1082
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• 2005

In this study, the run-up height and reflection property on slopes of S-berm and smooth slopes breakwaters are investigated by laboratory experiment. The run-up height analyzed the effect of reflection coefficient, surf similarity parameter. Measured reflection coefficients of smooth slope breakwaters are compared with those of S-berm breakwater with variable widths. In general, measured coefficients of S-berm breakwaters are smaller than those of smooth slope breakwaters.

• Journal of the Korean Geosynthetics Society
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• v.14 no.4
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• pp.23-33
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• 2015

Together with the wall stiffness, a berm has the role of deciding the stability of a temporary retaining wall before structure installation after excavation. Especially in case of loose or soft soil excavated ground, the role of berm is very important. In this study, the measurement data obtained from the temporary retaining wall in the bermed excavation site in urban and numerical analysis are used to investigate the effects of berm's dimension (width and slope), excavation depth and ground property on the maximum horizontal displacement of the temporary retaining wall. The measurement data indicated that the wall displacement varied to the berm's width. That is, as the berm width decreased, the wall displacement increased. As a result of numerical analyses, the maximum wall displacement increased as slope increased and berm width decreased. This means that the berm is effectively restrained to the wall displacement. As excavation depth increased, the effect of berm's slope and width increased. In case of the same berm condition, the wall displacement restrained as ground property increased.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.1919-1924
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• 2006

In this study, the run-up of water waves on slopes of s-berm breakwaters was investigated by performing a series of hydraulic experiments. The run-up height was analyzed in detail by using the effects of wave steepness and surf similarity parameter. In general, the run-up heights were decreased as the height and the width of berm were increased. However, the variation of run-up height was small for change of wave steepness and surf similarity parameter.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2003.05a
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• pp.121-127
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• 2003

Wave overtopping is one of the most important hydraulic responses of breakwater because it significantly affects its functional efficiency, the safety of transit and mooring on the rear side, wave transmission in the sheltered area, rear side armor stones and to some extent, the structural safety itself. In this study, hydraulic model tests has been carried out to investigate the influence of berm's size on overtopping rate by maximum overtopping rate and mean overtopping rate. The hydrodynamic characteristics of berm breakwater by the overtopping rate can be summarized as follows: 1. It is better to use maximum overtopping rate than to use mean overtopping rate for design of coastal structures in the point of view of stability. 2. When construct berm to decrease energy of waves that it was needed to make breaking conditions of wave on the berm. 3. Under the relative length of berm was over 0.13 overtopping rate was significantly decreased. 4. Overtopping rate affected significantly by the relative length of yhe berm than height of the berm.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.18 no.2
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• pp.147-153
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• 2006

In this study, the run-up of water waves on slopes of s-berm breakwaters was investigated by performing a series of hydraulic experiments. The run-up height was analyzed in detail by using the effects of wave steepness and surf similarity parameter. In general, the run-up heights were decreased as the height and the width of berm were increased. However, the variation of run-up height was small for change of wave steepness and surf similarity parameter.

• Smart Structures and Systems
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• v.15 no.2
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• pp.299-314
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• 2015

Submersed rock-berm structures are frequently used for protection of underwater lifelines such as pipelines and power cables. During the service life, the rock-berm structure can experience several accidental loads such as anchor collision. The consequences can be severe with a certain level of frequency; hence, the structural responses should be carefully understood for implementing a proper structural health monitoring method. However, no study has been made to quantify the structural responses because it is hard to deal with the individual behavior of each rock. Therefore, this study presents a collision analysis of the submersed rock-berm structure using a finite element software package by facilitating the smoothed-particle hydrodynamics (SPH) method. The analysis results were compared with those obtained from the Lagrange method. Moreover, two types of anchors (stock anchor and stockless anchor), three collision points and two different drop velocities (terminal velocity of each anchor and 5 m/s) were selected to investigate the changes in the responses. Finally, the effect of these parameters (analysis method, anchor type, collision point and drop velocity) on the analysis results was studied. Accordingly, the effectiveness of the SPH method is verified, a safe rock-berm height (over 1 m) is proposed, and a gauge point (0.5 m above the seabed) is suggested for a structural health monitoring implementation.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.13 no.3
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• pp.202-208
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• 2001

Explicit approximation has been developed to estimate the run-up height on S-berm breakwater on the basis of Saville's hypothetical slope method. For the explicit expression of run-up height several relations are developed to represent the ratio of run-up height against breakwater slope with various conditions of water depth and wave steepness. For the verification of explicit approximation the results are compared with Saville's measurement data and simple expression of Delft Hydraulic Laboratory.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.6
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• pp.2303-2315
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• 2013

In general, the waterway was installed for drain water from steep slope and waterway cover was set up to prevent overflow and water separation at berm of waterway. In this study, hydraulic experiment was conducted to analyze the flow characteristics and enact standard design criteria of the waterway. Hydraulic experimental apparatus which can change the slope of waterway and the length of berm were installed to analyze of flow characteristics at the waterway. The slopes of waterway were $40^{\circ}$, $50^{\circ}$, $60^{\circ}$, and $70^{\circ}$ and the range of discharge were 1.0~5.6 ${\ell}/s$. The flow in berm was distinguished two types such as hydraulic jump and splash flow. These kinds of flows depended on the rates of discharge in waterway. When inlet discharge was below 1.1~2.0 ${\ell}/s$, the separation phenomenon of water was generated at upper and lower portion in berm by the splash flow. The scattering range of water particles and length of water separation was measured depending on the slope of waterway. The start point of scattering was about 20 cm(1.3B) from the place connected upper waterway with brem and the length of water separation was till 210 cm(3.5B) from the place connected lower waterway with brem. Therefore, the waterway cover needed to install from starting of berm to 1B and from the lower part of berm to 3.5B.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2002.10a
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• pp.113-118
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• 2002

Wave overtopping is one of the most important hydraulic responses of breakwater because it significantly affects its functional efficiency, the safety of transit and mooring on the rear side, wave transmission in the sheltered area, rear side armor stones and to some extent, the structural safety itself. The hydrodynamic characteristics of low crest breakwater by the overtopping rate can be summarized as follows: 1. It is better to use maximum overtopping rate than to use mean overtopping rate for design of coastal structures. 2. Maximum overtopping rate was increase with wave steepness (between 0.01 and 0.02). 3. Overtopping rate is decreased when relation length of berm was over wave length.

• Coastal and Ocean
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• v.3 no.1
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• pp.38-48
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• 2010