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基于二维波浪水槽实验,采用沙质斜坡概化海滩,分别选用规则波和椭圆余弦波进行实验,测量波浪作用前后的海滩剖面形态及断面沉积物粒径组成,探讨波浪作用下沙质海滩沉积物运动特征,包括剖面形态演化特征及其床沙分选规律.结果表明:沙质海滩剖面形态时空演化特征受波浪类型、波高、周期等因素影响,呈现出沙坝形态和滩肩形态,发现波浪Irribarren参数可以作为沙质海滩剖面演化形态的判别参数.在本实验条件下,Irribarren参数大,海滩剖面呈现滩肩形态;Irribarren参数小,海滩剖面则呈现沙坝形态.海滩床面沉积物在波浪作用下产生了明显的分选现象,波浪破碎产生的强烈紊动造成床面沉积物的起动、并为小颗粒的运动提供动力.水体紊动导致水流挟沙力降低,大颗粒泥沙在紊动较强区域产生沉积,部分被水流挟带发生向岸推移;小颗粒泥沙则随水流运动,在紊动较弱的区域分散沉积.
Based on the two-dimensional wave tank experiment, the sandy beach was used to generalize the beach. The regular wave and elliptic cosine wave were selected for experiment. The shape of the beach before and after wave action and the grain size of the sediment were measured. Including the characteristics of section morphological evolution and bed sediment sorting.The results show that the temporal and spatial evolution characteristics of sandy beach profile are influenced by wave type, wave height and period, showing the shape of sand bar and the shape of beach shoulder, and the wave is found Irribarren parameters can be used as discriminant parameters for the evolution of the sandy beach profile.Under this experimental condition, the Irribarren parameters are large, the beach profile is shoal-shoulder morphology, the Irribarren parameter is small, and the beach profile shows the shape of a barrage. Under the action of a clear sorting phenomenon, the strong turbulence caused by wave crushing caused the bed sediment to start and provide motivation for the movement of small particles.The turbulence of the water body led to a decrease in the sediment carrying capacity of the water flow, The sediment in the area with strong dynamic movement is partly deposited by the water flow and moves to the shore. The small particle sediment moves with the water flow, Weak dispersion deposition area.