• Journal of Korean Society of Coastal and Ocean Engineers
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• v.18 no.1
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• pp.69-83
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• 2006

A Level 3 reliability analysis has been performed for wave run-up and overtopping on a sloping seawall. A Monte-Carlo simulation was performed considering the uncertainties of various variables affecting the wave overtopping event. The wave overtopping probability was evaluated from the individual wave run-up by using the wave-by-wave method, while the mean overtopping rate was calculated directly from the significant wave height. Using the calculated overtopping probability and mean overtopping rate, the maximum overtopping volume was also calculated on the assumption of two-parameter Weibull distribution of individual wave overtopping volume. In addition, by changing wave directions, depths, and structure slopes, their effects on wave overtopping were analyzed. It was found that, when the variability of wave directions is considered or the water depth decreases toward shore, wave height become smaller due to wave refraction, which yields smaller mean overtopping rate, overtopping probability and maximum overtopping volume. For the same mean overtopping rate, the expected overtopping probability increases and the expected maximum overtopping volume decreases as approaching toward shore inside surfzone.

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 2001.08a
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• pp.37-41
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• 2001

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 2003.08a
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• pp.130-133
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• 2003

방파제의 사면 파괴는 파가 구조물에 도달하였을 경우 발생하는 도파가 주된 요인중의 하나로 작용한다. 도파란 파도가 해안구조물에 충돌하여 뛰어 오르거나 기어오르는 현상을 일컫는다. 뛰어오르는 파도의 정상까지의 수직거리를 도파고(h$_{R}$)라 한다. (중략)

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.5B
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• pp.463-472
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• 2009

The aim of this study is to examine the effect of beach curvature on wave fields in coastal area with Submerged Breakwaters using the 3D numerical model that is able to simulate directly interaction of WAve Structure Sandy beach (LES-WASS-3D). At first, the adopted model was validated through the comparison with an existing experimental data and showed fairly nice agreement. And then, the numerical simulations have been performed to investigate the effect of according to the variation of beach curvature. Based on the numerical results, the wave height, mean surface elevation, mean flow around submerged breakwaters and longshore distributions of run-up height have been discussed in relation to the variation of beach curvature.

• Journal of Korea Water Resources Association
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• v.35 no.6
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• pp.779-786
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• 2002

A boundary element method with a Lagrangian approach and B-spline technique is employed to investigate characteristics of solitary waves attacking on beach slopes. By comparing numerical solutions with available laboratory measurements, it is shown that the maximum run-up heights of the present model are more agreeable than those of the existing numerical model. Variations of run-up heights and velocity vectors for different slopes are also described. Characteristics of hydrodynamic pressure acting beach slopes are investigated in detail.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.34 no.3
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• pp.723-728
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• 2014

Hydraulic experiments are performed in order to verify the swash effect of seashore structures installed to prevent scouring. However, a great deal of investment and time are required for producing the test apparatus and seashore structure used to perform the hydraulic experiment. The swash effect can be predicted, however, by using a numerical model and validation can be done based on comparisons of the numerical model and hydraulic experiment analysis results, thereby saving the cost and time required for producing the test apparatus and seashore structure. Taking a polyhedral rubble mound structure as the subject, this study performed a comparative analysis of wave run-up and run-down height of the numerical model interpretative results and the hydraulic experiment results, and validated the interpretative simulation wave test modeling technique. The study also predicted the swash effect by using the numerical interpretation approach method, whereby the volume ratio and friction area of the rubble mound were varied for different results.

• 한국방재학회:학술대회논문집
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• 2008.02a
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• pp.229-232
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• 2008

The Central East Sea Tsunami caused huge damage to the eastern coast of the Korean Peninsula, eapecially Imwon port was damaged relatively strongly beacause of water depth variation which makes the wave concentration on this port. there are many virtual tsunami in east sea which has a possibility of happening. So, it is very important to expect the region which may be damaged by vritual tsunmis. In this study, modified dispersion-correction terms are used. The modified scheme has the advantage of using the constant spatial grid size and time step size even in real topography. Dynamic linking technique and staggered grid system are used. Using this model some cases of virtual tsunami was simulated and check the region which is occured maximum wave heights on the eastern sea of the Korean peninsula.

• Ocean Systems Engineering
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• v.12 no.4
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• pp.439-459
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• 2022

This paper describes experimental studies of impact pressure generated by breaking regular waves in shallow water on a vertical cylinder. Experimental work was carried out in a shallow water flume using a 1:30 - scale model of a vertical rigid circular hollow cylinder with a diameter 0.2 m. This represents a monopile for shallow water offshore wind turbines, subjected to depth induced breaking regular waves of frequencies of 0.8 Hz. The experimental setup included a 1 in 10 sloping bed followed by horizontal bed with a constant 0.8 m water depth. To determine the breaking characteristics, plunging breaking waves were generated. Free surface elevations were recorded at different locations between the wave paddle to the cylinder. Wave impact pressures on the cylinder at a number of elevations along its height were measured under breaking regular waves. The depth-induced wave breaking characteristics, impact pressures, and wave run-up during impact for various cylinder locations are presented and discussed.

• Journal of Ocean Engineering and Technology
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• v.15 no.4
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• pp.20-27
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• 2001

Recently numerical approaches for wave loads acting on the vertical caisson of breakwater, and resulting wave reflection and transmission coefficients have been performed. Although the numerical studies by Sulisz's(1997) and Kim et al.(2000) are suggested representatively, theoretical formulation for nonlinear wave pressure is not developed yet. And experimental results of Sulisz(1997) revealed that nonlinear uplift pressure on the caisson may be produced largely on the case of caisson founded on the high rubble mound. From the results of this study, the nonlinear theory for the uplift wave pressure acting on the caisson by applying boundary integral method of Green theorem is formulated, and also the characteristics of nonlinear uplift pressure and run-up height on the caisson are evaluated numerically, according to the variations of hydraulic properties of the rubble mound.

• Journal of Korea Water Resources Association
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• v.50 no.9
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• pp.647-652
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• 2017

Many islands are scattered around the southern area of the Korean Peninsula and they may be very vulnerable to unexpected tsunami attacks. During the East Japan Tsunami Event occurred on March 11, 2011, many islands located at the southern area were affected by tsunamis. In this study, maximum run-up heights of solitary waves on a circular island with asymmetrical crest lengths investigated by using a numerical model based on the shallow-water theory. The obtained results could be used by local authorities to establish a defense plan against unexpected tsunami invasion.