JP4896256B2 - Underwater placement method - Google Patents

Description

The present invention relates to an underwater placing method in which a landfill material obtained by adding a cement-based solidifying material to dredged sand or the like in a landfill is placed underwater without separating the dredged sand and the solidified material.

  A solidified material such as cement is added to dredged soil, and the solidified material can be used as a landfill material.As a method of landfilling such a landfill material in water, (1) A method of placing a landfill material in water via a tremmy tube or a chute, (2) A placement port at the lower end of a vertically suspended casing is always buried in the existing landfill at a certain depth. In general, the method of placing the landfill material underwater is common.

Japanese Patent Laid-Open No. 4-55514 JP-A-64-58716

However, when the landfill material is driven in water by the conventional method described above, there are the following problems.
In the construction method using tremmy pipes and chutes described in (1) above, the tremmy pipes and chutes are filled with water, and the dredged material and solidified material are separated while the landfill material reaches the bottom of the water. There was a problem that quality could not be ensured and water pollution occurred.
In the method (2) of the method of embedding the lower end of the vertically suspended casing in the already-filled soil at a constant depth, the lower end of the casing is moved by moving the casing in the vertical direction. It is necessary to always manage the height of the housing, and this management is cumbersome, and when the water depth changes, such as at the time of tidal tide, There is difficulty in supplying landfill materials. In addition, the landfill material cannot be driven continuously while moving the ship. Also, depending on the landfill material, such as when there is a lot of sand, the construction management is difficult because the pressure rises in the casing.
The present invention has been devised in view of the above circumstances, and the object of the present invention is to ensure the quality of landfill material, to minimize water pollution, and even if the water depth changes. It is an object of the present invention to provide an underwater placing method that can supply landfill material without hindrance and that can continuously place landfill material while moving a ship.

In order to achieve the above object, the underwater placing method of the present invention is provided with a frame member extending along the length direction of the tubular body on one end side of the tubular body, and the tubular body is disposed on the one side. The end of the screw blade is supported so as to be able to swing up and down by the hull through the frame member so that the end portion of the screw blade is always positioned on the water surface. And the motor is disposed on the frame member so as to be movable in the longitudinal direction of the tubular body, and the motor and screw blades are slid along the extending direction of the tubular body on the frame member. A hydraulic cylinder is provided to respond to changes in the depth of the water bottom, and the pipe body is swung up and down so that the other end of the pipe body always faces a location that is a predetermined distance away from the water bottom. Supplying landfill material from one end of the body The screw blade is rotated inside the tube body to push the tube body in a state in which the landfill material is in close contact, and is placed on the bottom of the water. During maintenance, the motor and the screw blade are connected to the tube body by the hydraulic cylinder. The reclamation material is continuously cast while moving the hull by swinging the pipe body up and down in response to changes in the depth of the water bottom. It is characterized by that.

According to the present invention, since the landfill material is pushed forward in a state where the inside of the tube is in close contact, the landfill material is less likely to be separated, and therefore the quality of the landfill material can be ensured, and water pollution can be prevented. It can be minimized.
In addition, by swinging the tube, it is possible to easily cope with changes in water depth such as during tidal periods.
In addition, it is possible to continuously landfill landfills on the seabed with uneven height.

It is a top view of an underwater driving vessel. It is a front view of the underwater placing ship in the state where the landfill material is placed underwater. It is a front view of an underwater driving device. It is a top view of an underwater driving device. It is a front view at the time of movement of an underwater driving vessel. It is explanatory drawing of the positional relationship of an underwater driving ship, a solidification processing ship, a solidification material plant ship, and a soil conveyance ship.

Hereinafter, the underwater placing method of the present invention will be described with reference to the accompanying drawings.
FIG. 6 is an explanatory diagram of the positional relationship among the underwater driving ship, the solidification processing ship, the solidification material plant ship, and the earth transporting ship.
As shown in FIG. 6, for example, the underwater driving ship 12, the solidification processing ship 14, and the solidification material plant ship 16 are arranged on the sea via anchors, and in FIG. 6, a symbol R indicates an anchor rope.
The dredged sand is transported from the earth transport ship 18 to the solidification processing ship 14, the cement milk produced by the solidification plant ship 16 is supplied to the solidification processing ship 14, and the dredged sand and cement milk are stirred and mixed in the solidification processing ship 14. It is considered as landfill material. Then, the landfill material is pumped to the underwater placement ship 12 by air through the offshore pipe H, and is placed on the seabed by the underwater placement ship 12.

FIG. 1 is a plan view of the submerged vessel, FIG. 2 is a front view of the submerged vessel with the landfill material being submerged, FIG. 3 is a front view of the submerged device, and FIG. FIG. 5 is a plan view of the installation apparatus, and FIG.
As shown in FIG. 1, the underwater vessel 12 includes a hull 20, and the hull 20 is separated from a cyclone 22 that separates air from landfill material that is pressure-fed via a marine pipe H, and the air. A mud storage tank 24 for storing the landfill material, an underwater placing device 26 for placing the landfill material supplied from the mud tank 24 underwater, and a swing drive means for swinging the underwater placement apparatus 26 up and down. 28.
The hull 20 is formed in a rectangular shape in plan view in which the length in the front-rear direction is larger than the width in the left-right direction. In FIG. Indicates.

The underwater driving device 26 is disposed on a side portion of the hull 20 that is located at an end portion in the left-right direction of the hull 20.
The underwater driving device 26 includes a tubular body 30 that extends in a straight line and has a long length corresponding to the longitudinal length of the hull 20, and a hopper 32 that is provided at one end of the tubular body 30 and into which a landfill material is charged. The screw blade 34 that is rotatably disposed inside the tube body 30 and rotates to push the inside of the tube body 30 in close contact with the landfill material, and the screw blade 34 provided on one end side of the tube body 30 is rotated. It is comprised with the drive part 36 to drive.

The pipe body 30 has a long length corresponding to the front-rear length of the hull 20, and the length direction thereof is arranged in the front-rear direction of the hull 20. In this case, the length of the tubular body 30 may be longer than the front-rear length of the hull 20, or may be shorter or substantially the same, but in short, the length of the tubular body 30 is the same as that of the hull 20. It has a sufficiently long length as compared with the front and rear lengths.
In the present embodiment, two pipe bodies 30 are provided side by side so as to extend in parallel to each other, and screw blades 34 are provided in each pipe body 30, and the screw blades 34 are provided up to the tip of each pipe body 30. Is extended.
In this embodiment, a flexible tube 38 made of a flexible material such as rubber is attached to the other end of the tube 30 so as to extend coaxially with the tube 30. . The screw blade 34 extends to the tip of each tube body 30, but does not extend inside the flexible tube 38. By providing the flexible tube 38 at the distal end of the tubular body 30 in this way, it is configured to minimize damage to the underwater driving device 26 caused by the tubular body 30 coming into contact with the seabed.

The hopper 32 is provided on the upper surface of one end of the two pipe bodies 30.
The hopper 32 is single, and the landfill material is put into the hopper 32 from the mud storage tank 24, and the landfill material is put into the two pipe bodies 30 from the hopper 32.
In the present embodiment, as shown in FIG. 3, a stirrer 3202 is disposed at the bottom of the hopper 32 so that the landfill material is uniformly introduced into the tube body 30 from the hopper 32. In addition, the opening 3204 of the hopper 32 is formed long in the front and rear directions so that the reclamation material can be smoothly put into the hopper 32 from the mud storage tank 24 regardless of the inclination of the tube body 30. The inlet 2402 of the mud storage tank 24 faces.

A frame member 40 is provided on the lower surface of one end of the two tube bodies 30 so as to extend on the extension of the tube body 30. The frame member 40 includes a bracket 2010 and a bracket 2010 fixed to the hull 20. It is supported by the hull 20 via a pin 2012 inserted through the frame member 40, and the pin 2012 is located in a portion near the front portion of the hull 20. As a result, the tube body 30 is supported so as to be swingable at a position near the front portion of the hull 20 with the pin 2012 as a fulcrum so that the hopper 32 is always located on the water surface.
The drive unit 36 is constituted by a hydraulic or electric motor, and two are provided corresponding to the screw blades 34. And the upper end of each screw blade | wing 34 is each connected with a motor, and each motor is arrange | positioned on the frame member 40 so that the movement along the longitudinal direction of the tubular body 30 is possible.
Two hydraulic cylinders 42 are provided at the end of the frame member 40, and the piston rod of each hydraulic cylinder 42 is connected to a corresponding motor. The body 30 is configured to slide along the extending direction. By sliding the screw blades 34 with respect to the tubular body 30 in this way, it becomes very convenient during maintenance to remove clogging and the like.

The swing drive means 28 includes a winch 2802 disposed on the hull 20, a wire 2804 wound around the winch 2802, and a wire guide portion 2806 provided at the outer edge in the width direction at the rear of the hull 20. ing.
The end of the wire 2804 drawn from the winch 2802 is connected to a position near the tip of the tubular body 30 through the wire guide portion 2806, and the underwater driving device 26 swings up and down about the pin 2012 as a fulcrum by driving the winch 2802. Is configured to do. The wire guide portion 2806 includes a pillar 2806A having a predetermined height and a pulley that guides the wire 2804 disposed at the upper end of the pillar 2806A so that the tube body 30 can be lifted horizontally at the side of the hull 20. 2806B.

Next, the case where the landfill material is placed on the seabed by the underwater placement ship 12 will be described.
In the underwater driving vessel 12, the swing angle of the tubular body 30 via the winch 2802 and the wire 2804 so that the distal end of the tubular body 30, that is, the flexible tube 38 faces a predetermined distance from the seabed, That is, the swing angle of the underwater driving device 26 is adjusted.
The landfill material is supplied from the solidification processing vessel 14 to the cyclone 22 of the underwater placement ship 12 via the offshore pipe H, and after the air is separated by the cyclone 22, the landfill material is stored in the mud storage tank 24 and stored. The mud tank 24 is supplied to the hopper 32, and the landfill material is supplied onto the screw blades 34 through the stirrer 3202. The separated air is safely discharged through the air discharge pipe J.

And although the screw blade 34 is rotationally driven by the drive part 36 and the inside of the pipe body 30 is filled with seawater, the landfill material is pushed forward in a state in which the inside of the pipe body 30 is in close contact with the screw blade 34, It is driven from the flexible tube 38 to the seabed.
In this case, since the landfill material is pushed forward in a state where the inside of the tube body 30 is in close contact, the dredged sand and the solidified material are not separated inside the tube body 30 before reaching the seabed.
Further, since the swinging angle of the tube body 30 is adjusted by the swinging drive means 28 so that the flexible tube 38 faces a place away from the seabed by a predetermined distance, the landfill pushed out from the flexible tube 38 is buried. There is little risk that the material will be separated into dredged sand and solidified material on the seabed, and there is also little risk of contaminating seawater. That is, the quality of the landfill material can be ensured, and water pollution can be minimized. In this embodiment, the length from the hopper 32 to the flexible tube 38 is about 30 m, and a distance of about 2 m is opened between the flexible tube 38 and the seabed. Can be placed.

Further, the tube body 30 is swung by the rocking drive means 28, thereby changing the depth (height from the seabed) of the tube body 30, that is, the depth of the flexible tube 38 (height from the seabed). Because it can, it can easily cope with changes in water depth, such as during tidal periods.
Further, if the hull 20 is moved while the tube body 30 is swung by the rocking drive means 28 according to the depth of the seabed, the landfill material is continuously placed on the seabed having a non-uniform height. It is also possible to go. The hull 20 is moved in this case, for example, when the hull 20 is moved forward, the anchor rope R is fed out in the ship winch 2002 arranged at the rear of the hull 20, and the hull 20 is moved to the front of the hull 20. This is performed by winding up the anchor rope R in the arranged ship sending winch 2002.
Further, the tube body 30 is arranged with its length direction facing the front-rear direction of the hull 20, and one end side of the tube body 30 can swing up and down via a pin 2012 at a portion near the front of the hull 20. Since the wire guide portion 2806 that supports and receives the load of the wire 2804 connected to the other end side of the tube body 30 is disposed at the rear portion of the hull 20, the weight of the long and heavy underwater driving device 26 is increased. As shown in FIG. 2, the stability of the hull 20 during the placing operation is improved, and as shown in FIG. 5, the tube 30 is horizontally placed on the sea surface. This is extremely advantageous for improving the running stability of the hull 20 when moving as a state.

  In the above embodiment, the case where the underwater driving device 26 is disposed on the side in the width direction of the hull 20 has been described. However, the hull is divided in the width direction at portions other than the front end or the rear end of the hull. It is also possible to arrange an underwater driving device between these divided hulls.

As is clear from the above description, according to the underwater placing method of the present invention, the quality of the landfill material can be secured, water pollution can be suppressed to a minimum, and even if the water depth changes, the landfill is reclaimed. The material can be supplied without hindrance, and the landfill material can be continuously placed while moving the ship.
Also, during maintenance, the screw blades 34 and the motor can be slid along the extending direction of the tubular body 30 by the expansion and contraction operation of the hydraulic cylinder 42, so that clogging and the like can be removed, which is very convenient.

DESCRIPTION OF SYMBOLS 12 Underwater placing ship 20 Hull 22 Cyclone 24 Mud storage tank 26 Underwater placing device 28 Swing drive means 30 Tubing body 32 Hopper 34 Screw blade 36 Drive part

Claims (3)

A frame member extending along the length direction of the tubular body is provided on one end side of the tubular body,
The tube is supported so as to be able to swing up and down with the hull through the frame member so that the one end is always located on the water surface,
A motor for rotating a screw blade inserted into the tube is connected to an end of the screw blade, and the motor is disposed on the frame member so as to be movable in the longitudinal direction of the tube,
The frame member is provided with a hydraulic cylinder that slides the motor and screw blades along the extending direction of the tubular body,
Corresponding to the change in the depth of the water bottom, the pipe body is swung up and down so that the other end of the pipe body always faces a place away from the water bottom by a predetermined distance,
Supplying landfill material from one end of the tube, rotating the screw blades inside the tube and pushing the tube body in close contact with the landfill material, so as to be placed on the bottom of the water,
During maintenance, the motor and screw blades are slid along the extending direction of the tubular body by the hydraulic cylinder ,
The placing of the landfill material is performed continuously while moving the hull up and down by moving the pipe up and down in response to a change in the depth of the water bottom,
An underwater placement method characterized by this. The tubular body has a long length corresponding to the longitudinal length of the hull, the tubular body is disposed with its length direction directed in the longitudinal direction of the hull, and the frame member is formed of the hull. A wire that is swingably coupled to one of the front part and the rear part, and that the vertical swing of the tube is suspended from the other part of the front or rear part of the hull with the joint part as a fulcrum The underwater placing method according to claim 1 , wherein the underwater placing method is performed. 3. The underwater placing method according to claim 1, wherein the landfill material is a dredged material obtained by adding a cement-based solidifying material to dredged sand.

Images