• Journal of Korean Society of Coastal and Ocean Engineers
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• v.30 no.2
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• pp.51-60
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• 2018

This study was conducted to observe the effects of gravity and infra-gravity wave of detached submerged breakwater in the coast of Yeongnang-dong, Sokcho, as analyzing continuous wave data by performing field observations on the front area (W0) and rear area (W1, W2). Wave transmission coefficient ($K_t$) of submerged breakwater was analyzed in two parts, short-period wave (gravity wave) and infra-gravity wave. The wave energy reduction effect was analyzed and compared with the value of the design. In case of above wave height 2.0 m at the front area (W0) of the submerged breakwater, the short-period wave height at point W1 is reduced by about 65% and the short-period wave height at point W2 is reduced by about 59%. The depth of crest of submerged breakwater conducted in a sea area differs from the design, and the wave energy reduction effect is analyzed to be smaller than the design plan. The infra-gravity waves were amplified to 2.11 and 1.71 at the W1 and W2 points, respectively, and the wave height at W2 point was smaller than that at W1 point.

• 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.