| 摘要 |
PURPOSE:To improve working efficiency, by a method wherein a levelling arm is rotated as stones are pressed by the own weight of the levelling arm being suspended from a rubble-stone levelling ship down onto stones which are charged and spread over the sea bottom being levelled to some degree. CONSTITUTION:Stones are charged and spread over the sea bottom through a tremie 5 from a rubble-stone ship, and during movement of a ship hull, a blade 3 is protruded downward to cross-cut the stones to level them to some extent. Thereafter, a surface plate 4 located at the lower end of an arm 2 is rotated as the own weight of the arm 2 is applied on the stones in a condition in which the blade 3 is retracted above. |
