| 摘要 |
<p>A dredging method and a dredging apparatus which can efficiently suck large quantities of sand and gravels deposited on the bottom of dams, rivers, harbours, etc., convey them with much saved energy as possible and can prevent diffusion of turbid water. To accomplish this object, an apparatus includes a case (2, 102) laid down into water in communication with the atmosphere. A suction pipe (3, 105) having a suction portion (7, 106) at the lower end thereof is connected to this case (2, 102). The apparatus further includes a drain pump (12, 124) for draining water inside the case (2, 102) and forming a level difference between the water level inside the case (2, 102) and the external water level and a container (109) removably disposed at an intermediate portion of the suction pipe (3, 105). The sand and gravels are sucked from the suction pipe (3, 105) into the container (109) by the siphon principle due to the level difference between the external water level and the water level inside the container (2, 102), and the container (109) is cut off and the sand and gravels are taken out when the container (109) is full.</p> |
