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

对天然海滩如何减轻风暴能量的科学理解现在已经成为海岸工程专业考虑海滩作为软岸保护结构的基础。以海滩营养项目为重点，通过相互调查对日本、美国和欧盟各自的海岸保护策略进行了评价。获得的主要结果是：欧盟案例：突出并讨论了欧盟国家的海滩填筑情况，包括一般情况、项目类型和目标、设计和评估程序、法律框架和财务方面。正如预期的那样，在被调查的国家之间发现了显著的差异。总的来说，研究表明，南欧国家学习荷兰和德国的做法是非常有益的，特别是在长期沿海管理和定期监测沿海形态方面。另一方面，荷兰最近的经验表明，他们的法律体系有点过于僵化，导致当地的自动更新，而这对于实现全球目标是不必要的。美国的例子：美国陆军工程兵团1971年的一项研究发现，2600英里（4200公里）的土地正在经历严重的侵蚀。1950年至1995年间，海军陆战队建造了56个大型海岸保护项目，覆盖210英里（340公里），约占侵蚀面积的8%。1970年，海滩营养从硬结构（20%）转变为软结构（80%），这种转变一直持续到今天。到1993年为止的实际建筑费用共计6.7亿美元或每年约1 500万美元。1995年美元；调整后的成本为15.8亿美元，即每年3400万美元。在涉及海滩营养的49个项目中，放置的沙子总量约为1.9亿立方码（cy）。平均单位砂成本为3.55美元/年。

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.