A new closed clamshell bucket with a volume of 20 m3 was tested in the sea in order to minimize the 3 Rs (residual, resuspension, release). It was found to be able to meet the Japanese standards of turbidity generation unit (TGU) of 3.5 kg m-3 that is about a half of that of Hopper.
II. 재료 및 방법
1. 밀폐형 그랩 준설