FIELD EXPERIMENTS ON LONGSHORE SAND TRANSPORT IN THE SURF ZONE
FIELD EXPERIMENTS ON LONGSHORE SAND TRANSPORT IN THE SURF ZONE
复制标题
冲浪区沿岸输沙现场实验
DOI：
10.1061/9780872623736.061
复制
发表时间：
2010
期刊：
影响因子：
--
通讯作者：
K. Horikawa
中科院分区：
文献类型：
--
作者：
N. Kraus;M. Isobe;H. Igarashi;K. Horikawa
在天然海滩和结构物附近的海滩上进行了八个荧光砂示踪实验，以测量短期沿岸输沙率。在穿过碎波带的线上注入多达四种不同颜色的示踪剂，以研究沿岸砂的前进速度和输送率的近海分布。示踪剂的平流速度，v，和混合到床的深度，B，确定从大量的核心，在整个采样区的现场。砂平流速度和混合深度不是恒定的整个冲浪区，但通常表现出最大的朝向海岸线或朝向破碎线，或在这两个区域。局部破碎波高H。和碎波带的水平流速（产生平均沿岸流速V）也被测量。数据进行了解释与简单的尺寸参数，得到以下结果：B = 0.027 H，，v = 0.011 V，和体积传输率Q = 0.024 HV.协议之间也被发现测量的总沿岸输沙率和预测表达式，由于Bagnold涉及破碎波功率和平均沿岸流速。虽然结果似乎合理和一致的，一个问题仍然存在，在大多数实验中记录在较长的采样时间沿海岸的示踪剂平流速度明显下降。
Eight fluorescent sand tracer experiments were performed in energetic surf zones on natural beaches and on beaches near structures to measure the short-term longshore sand transport rate. Tracer of up to four distinct colors was injected on a line crossing the surf zone to investigate the on-offshore distributions of the longshore sand adveetion velocity and transport rate. The tracer advection velocity, v , and the depth of mixing into the bed, b, were determined from large numbers of cores taken in situ throughout the sampling area. The sand advection velocity and mixing depth were not constant across the surf zone, but usually exhibited a maximum either toward the shoreline or toward the breaker line, or in both regions. The local breaking wave height, H. , and horizontal current velocity in the surf zone (yielding an average longshore current velocity V) were also measured. The data were interpreted with simple dimensional arguments to give the following results: b = 0.027 H,, v = 0.011 V, and the volumetric transport rate Q = 0.024 H V. Agreement was also found between the measured total longshore sand transport rate and a predictive expression due to Bagnold involving the breaking wave power and average longshore current velocity. Although the results appear reasonable and consistent, a problem remains concerning the apparent decrease in tracer advection speed alongshore recorded in most experiments at the longer sampling times.