不规则破碎波作用下直立堤前泥沙运动及冲淤特性

The scours in front of breakwaters will affect the stability of the structure and should be considered in design and construction. However, most results on scours at the foot of breakwater are that caused by regular waves, and show that the scours caused by broken waves are serious than that due to non-breaking waves. The waves in field are random, therefore, the study on scours in front of breakwaters should consider irregular waves..The sediment movement and scouring characteristic of sand bed in front of breakwaters by irregular breaking and broken waves are investigated systematically. Experiments were conducted in a wave flume, the seabed slope i considered was 1/60,1/30 and 1/15 respectively, the sand diameter ds was 0.10-1.4mm, the water depth at the breakwater h1 was 0.10-0.32m, and wave spectrum was different. The characteristic of irregular breaking and broken waves in front of breakwater, scouring and depositing mechanism, scouring and depositing patterns, criterion for differentiating the scouring and depositing patterns, and the protective measure for these scours, comparison of the scouring and depositing of sand bed under the action of irregular and regular breaking and broken waves are discussed, model law for model sediment and equilibrium scouring trough etc., are investigated. In order to study the wave movement in front of breakwaters, a numerical tank of irregular waves was developed based on the MAC method (Maker and Cell method), in which, the source generation of waves is applied, the sponge layer for wave damping absorber combined with the Sommerfeld radiation is used to the open boundary..

研究不规则波浪传至堤前发生破碎（远破波、近破波）后，堤前波浪的运动规律；堤前沙床泥沙运动机理；堤前沙床的冲淤特性。为防波堤、护岸堤等海岸建筑物的设计和建设提供理论依据；目前国内外尚未开展这方面的研究，本项目具有一定的开创性和重要的理论价值。