파랑 내습시 하구역 호안의 월파량에 관한 연구

Abstract

Wave overtopping has been studied under the view of its reducing capability of the various wave dissipating structures. Therefore, researches for the effect of wave overtopping caused influx of stream are insufficient. In this study, it was analyzed the effort of wave overtopping by influx of stream on the breakwater around the estuary. This study was carried out to calculating wave overtopping rate using horizontal and vertical 2D wave numerical modeling for the design of breakwater stability. To accomplish the main purpose, investigate the wave deformation according to the input and boundary conditions (incident wave, variation of river width, water elevation) and quantify the wave overtopping rate on the breakwater around estuary. Two main results are summarized as follows: First, long-period wave energy was transmitted upstream better than short-period it. Wave heights was increased about from 8 to 18 percents in time of twice river's width using numerical wave transformation model(STWAVE). The wave deformation around estuary was dominantly affected on the shape of estuary, especially width of estuary is the most important parameter. In other words, wave energy will be dissipated around estuary as width of estuary decrease. Second, the value of water level rising is 0.12 m which is considered influx of stream only, but 0.23 m considered both influx of stream and storm surge in Suyeong bay. This results indicated that the condition which is considered storm surge has double value more than another condition. In order to carried out overtopping rate, the numerical wave channel model(CADMAS-SURF) was operated. Using calculated the wave condition on the breakwater, the overtopping rate considered both influx of stream and storm surge is increased by 0.07 m³/sec/m(about 1.8 times) in the area A and the overtopping rate is increased by 0.2 m³/sec/m(about 2times) in the area B than the condition which is considered storm surge only. From the results, damage possibility in the area B is higher than area A. We will be considered to adopt influx of stream if and when the breakwater be designed around estuary.