Mutual Evaluation of Beach Erosion Control in JAPAN,EC,USA

对天然海滩如何缓解风暴能量的科学理解，现在已成为海岸工程专业人员考虑将海滩作为软海岸防护结构的基础。以滩涂养生项目为重点，对日本、美国和欧盟的海岸保护战略进行了相互考察和评价。取得的主要成果是：欧盟案例：从总体情况、项目类型和目标、设计和评估程序、法律框架和财务方面对欧盟国家的海滩填筑情况进行了重点讨论。正如预期的那样，被调查的国家之间发现了显著的差异。总体而言，这项研究表明，南欧国家了解荷兰和德国的做法，特别是关于长期沿海管理和定期监测沿海地貌的做法，将是非常有益的。另一方面，荷兰最近的经验表明，他们的法律制度有点过于僵化，导致了自动的局部补给，这对于达到全球目标的美国来说是不必要的：美国陆军工程兵团1971年的一项研究发现，2600英里(4200公里)正在经历严重的侵蚀。在1950年至1995年间，陆军陆战队修建了56个大型海岸保护工程，覆盖210英里(340公里)，约占侵蚀总量的8%。1970年，随着海滩的滋养，从硬结构(20%)到软结构(80%)的转变一直延续到今天。截至1993年的实际建筑费用总计6.7亿美元，即每年约1500万美元。1995年美元；调整后的费用为15.8亿美元，即每年3400万美元。在49个涉及海滩滋养的项目中，放置的沙子总量约为1.9亿立方码(Cy)。平均单位沙子成本为3.55美元/Cy。

Scientific understanding of how natural beaches mitigate storm energy has now become the basis for the consideration of beaches as soft shore protection structures by the coastal engineering profession. Focusing on the beach nourishment projects, own shore protection strategies in JAPAN, USA and EU has been evaluated by mutual survey. The main results obtained are :EU case : The beach fill situation in the countries of the European Union is highlighted and discussed with respect to the general situation, project type and objectives, design and evaluation procedures, legal framework, and financial aspects. As expected, significant differences were found between the investigated countries. In general, the study shows that it would be very profitable for south European countries to learn about the Dutch and German practices, particularly regarding the long-term coastal management and the regular monitoring of the coastal morphology. On the other hand, recent Dutch experience has shown that their legal system is a bit too rigid leading to automatic local renourishments that are unnecessary to reach the global objectiveUSA case : A 1971 study by the US Army Corps of Engineers found 2600 miles (4200 km) to be experiencing critical erosion. Between 1 950 and 1 995 the Corps constructed 56 large shore protection projects that covered 210 miles (340 kin) or about 8 percent of that eroding. In 1970, a shift from hard structures (20%) to soft structures (80%) as beach nourishment occurred that continues today. Actual construction costs to 1993 totaled $670 million or about $15 million per year. In 1995 dollars ; adjusted costs were $1,580 million or $34 million per year. The total volume of sand placed was about 1 90 million cubic yards (cy) for the 49 projects that involved beach nourishment. Average unit sand cost was $3.55 per cy.