摘要
介绍了利用泥沙捕获器观测破波带泥沙垂直分布结构的现场实验方法和基本程序 ,以及利用实验结果计算泥沙通量的方法。研究表明 ,近岸带泥沙运移通量及其在垂向上的分布受破波带相对位置和海滩地形变化的影响。在破波点附近 ,波浪的搅动和流场作用强 ,泥沙运移通量增大 ,泥沙在波浪的作用下可以大量进入垂直水体以悬移和跃移的方式运移。在本实验中 ,破波点附近的泥沙在距海底 1 0 0 cm的垂直水体中运移 ,通量垂向向上逐渐减小。远离破波点 ,泥沙运移通量和进入垂直水体的高度明显下降。在地形变化复杂的有坝海滩 ,沙坝顶部的泥沙运移通量最大 ,泥沙进入垂直水体运移的机率增加 ,而在沙坝间的沟槽内 ,波浪和海流作用减弱 ,泥沙通量和垂向进入水体运移的比例下降。
The field experiment method and basic procedure for observing the sediment vertical distribution in surf zone by using sediment trap are introduced, and the method for calculating the sediment flux using the experiment results is also described. It is shown from the study results that the sediment flux and its vertical distribution in the nearshore zone are affected by the relative position of surf zone and the beach topography. The sediments near the breaking line are disturbed by breaking wave and strong current to increase the sediment flux, and a large amount of sediments are suspended and transported as suspended load and saltation load. During the experiment period, the sediments near the breaking line were transported in the water column at distances of 0 to 100 cm from seabed, and the sediment flux gradually decreased upward; and the sediment flux and suspension height far away the breaking line decreased significantly. On the barred beach, with complex topography, the maximum sediment flux occurred on the top of barrier, and more sediments were transported as suspended load; in contrast, less sediment flux and suspended load occurred in the troughs between barriers due to the weakened wave and current actions.
出处
《海岸工程》
2003年第2期67-77,共11页
Coastal Engineering
基金
国家自然科学基金资助项目--破波带泥沙垂直分布结构和运移机制观测与研究 ( 40 0 6 0 0 0 6 )