2012 Volume 25 Issue 3 Pages 65-74
ABSTRACT : As per a national government strategy to revive and grow fishery resources by improving and developing deep-sea fishery environment in the exclusive economic zone (EEZ) around Japan, Fisheries Agency of Japan ordered a project to build artificial upwelling rock-mound reefs in the 150m-deep sea, offshore of Nagasaki Prefecture. The construction was done by dumping 16,900m3 of rocks (1t/pc) from barges under severe weather and rough marine circumstances.
In this project, a series of barge navigational guide systems were used to set quickly and keep steadily a barge in the target position to dump rocks accurately to the designated position on the 150m-deep seabed even under such severe conditions. Furthermore, a series of simulation systems to determine optimal approaching directions and dumping points for the barge were also used in order to build the rock-mound reefs accurately in an expected. These technologies introduced herein are effective and contribute to the construction of artificial upwelling rock-mound reefs in the deep sea.
