Controlling fine wind-blown sand on beaches

海滩营养现在是美国和荷兰等一些国家海岸保护的主要选择，并且在其他国家，特别是西欧和日本，越来越多地使用。填充材料必须取自海上取土区，且该材料的直径通常较小。这种细沙很容易被风吹走。关于细砂的风吹输送，人们知之甚少。此外，在平坦的沙表面上输送的风沙通常集中在靠近表面的一层。然而，相当数量的风沙可能会越过几米高的防风林，并被运到内陆。目前还没有一个完整的理论来描述这一现象，本研究的目的就是为了解决这一问题。1）建立了细沙粒输沙率公式; 2）解释了穿越高风障向内陆输沙的现象并估算了输沙量; 3）制定小障碍物周围局部积沙的对策。最终报告中给出了与主题第一和第二相关的研究结果。第三个主题正在研究中，结果将在不久的将来公布。

Beach nourishment is now the principal option for shore protection in some countries such as the USA and The Netherlands, and it is being increasingly employed in other countries, particularly in Western Europe and Japan. Fill material must be taken from offshore borrow areas and this material is usually small in diameter. Such fine sand is easily transported by the wind. There is little knowledge about wind-blown transport of fine sand. In addition, wind-blown sand that is transported over a flat sand surface is normally concentrated to a layer near the surface. However, considerable amount of wind-blown sand may cross over wind-breaks that are several meters high and be transported inland. At present, there is no comprehensive theory to describe this phenomenon.The purpose of this study is to solve the problems.Three sub three themes are stated in this study concerned with the fine sand ;1)to establish the sand transport rate formula for fine sand,2)to explain the phenomenon and estimate sand that cross over the high wind-blacks and transported inland,3)to develop countermeasures for the local accumulation of blown sand around small obstacles.Research results concerned the theme first and second are given in the final report. Third theme is under research and results will be published in near future.