Sediment discharge device and sediment discharge method

摘要

PROBLEM TO BE SOLVED: To smoothly remove accumulated sediment irrespective of character of the accumulated sediment.SOLUTION: A tube 20 which is formed with a continuous slit-like opening part 22a along a longitudinal direction extends in a depth direction in accumulated sediment 14, and a lower end 22aL of the opening part 22a is defined at a predetermined depth. An output side end 20B of the tube 20 is disposed outside a dredging area. A flow of water W in the tube 20 generates a negative pressure at the opening part 22a which is exposed in an under water part 16 where an upper end 22aU is higher than an accumulating face 14S of the accumulated sediment 14 and the water W is sucked into the tube 20 from the opening part 22a. And the flow of the water W into the tube 20 from the opening part 22a imparts a shear force to the accumulated sediment 14, and the accumulated sediment 14 is sucked into the tube 20 via the opening part 22a from a surface layer part 14S of the accumulated sediment 14. Once the suction of the surface layer part 14S of the accumulated sediment 14 into the tube 20 begins, the erosion proceeds toward the deeper in the accumulated sediment 14.