| 摘要 |
<P>PROBLEM TO BE SOLVED: To restore beaches by controlling sediment flowing from rivers into the sea since the beaches have decreased or disappeared recently, while many of sand beaches and gravel beaches are formed by the sediment flowing down from the rivers to the sea. <P>SOLUTION: At a river mouth of a river, a spur dike is installed in a direction oblique to flow to weaken power of the sediment which has flown even to a sea bottom away from a shore due to rapid water increase, and a lot of sediment is deposited near the shore of the river mouth. Thus, sand beaches and gravel beaches that used to be formed by the sediment flowing from the rivers into the sea are restored. <P>COPYRIGHT: (C)2013,JPO&INPIT |
