一、前言近年来,随着河川流域的开发和沿岸土地的利用,海岸冲刷已成为众所周知的重大课题。对自然环境的保护问题,已引起各方面的高度重视。作为海岸防护的对策,很早就开始建造大量的护岸工程,如丁坝及离岸堤等各种海岸建筑物。尽管建筑经费在逐年增长,但就现状来看,各种建筑物尚未充分发挥作用。很久以前,地貌学家们研究了地貌的特性,他们发现:沙质海岸与入射波向线垂直的海岸,称为稳定海岸,并把它命名为“之”形海湾或“勾”状海湾。尤其是本文 I. Foreword In recent years, along with the development of the river basin and the utilization of land along the coast, coast erosion has become a well-known major issue. The protection of the natural environment has drawn great attention from all quarters. As a precautionary measure for coastal protection, a large number of revetments have long been started to be built, including various coastal structures such as dikes and offshore embankments. Although the funding for construction is increasing year by year, all kinds of buildings have not yet reached their full potential. A long time ago, geomorphologists studied the characteristics of the landscape. They found that the coast of the sandy and inland waves perpendicular to the incoming wave is called the stable coast and named it a “sea” or “hook”. Especially this article