JPH0720179Y2 - Underwater casting tremie tube - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to a tremy pipe for underwater pouring used for constructing improved soil by embanking improved soil on the bottom of the water.

[Prior art] In recent years, soft soil and fluidized sludge that make up soft ground are collected, and cement-based or polymer-based solidifying material is added to this to solidify it to improve it into good quality soil for reuse. It is thought to do. As one of the trials, it is also considered to collect sludge accumulated on the bottom of the water, solidify it to improve it to good quality soil, and embed it again on the bottom of the water to construct it on the improved ground.

Conventionally, the tremie method using a tremie pipe is generally known as a method for placing concrete in water, and this method is also used when constructing improved ground on the water floor.
A tremie pipe is usually a hollow cylinder of several meters in length that is screwed together at both ends, and is connected in multiple stages to form the desired length. It is generally considered that the improved ground is constructed by placing the soil near the ground surface where it is placed, and feeding the improved soil into the tremie pipe from the funnel-shaped hopper at the upper end of the tremie pipe.

[Problems to be solved by the invention] However, if a hollow cylindrical tremie pipe is inserted into water, the pipe below the water surface will be filled with water. The solidified improved soil separates and absorbs water and becomes fluidized again, resulting in deterioration of the quality of the improved soil. This also pollutes the water near the site.

In view of the above points, the present invention proposes a tremy pipe for underwater pouring, which can cast the improved soil on the bottom of the water without degrading the quality of the improved soil and without contaminating the water near the site. The purpose is.

[Means for Solving the Problems] In order to achieve the above object, the present invention has a hollow inner cylinder having a funnel-shaped hopper formed on the upper portion thereof with a discharge port at the lower side wall thereof, and a lower end thereof having an inner cylinder diameter. An inverted conical closing body with a larger diameter is fixed, a packing is attached along the outer peripheral portion on the upper surface of the closing body, and a screw is installed inside the inner cylinder of a motor mounted on a hopper. An outer cylinder connected to the drive shaft and having the same length as the inner cylinder on the outer side of the inner cylinder and freely movable up and down by the elevating means is loosely fitted. The present invention provides a tremy pipe for underwater casting, which is configured so as to come into contact with a packing attached to the upper surface of the closing body and expose the discharge port of the cylindrical body to the outside when rising.

[Operation] In the underwater casting tremie pipe according to the present invention, the outer cylinder is lowered by the elevating means and the lower end of the outer cylinder is brought into contact with the upper surface of the closing body so that water does not enter the inner cylinder. , It is suspended by a crane on a pontoon and descended into the water. When the blocker at the bottom of the tremie pipe reaches the bottom of the water, the electric motor is driven to sequentially feed the improved soil from the hopper while rotating the screw installed in the inner cylinder, and the screw causes the improved soil to move downward in the inner cylinder. And send it. When the improved soil reaches the closed body at the lower end of the inner cylinder and fills the inner cylinder, the elevating means is driven to raise the outer cylinder, and the outlet of the inner cylinder is exposed in water. After that, the improved soil is pushed out from the discharge port by the force of the screw and placed on the bottom of the water.

When the driving is completed, part of the improved soil remains in the lower part of the inner cylinder, and the elevating device is driven to lower the outer cylinder while water does not enter the inner cylinder through the discharge port, and the lower end of the outer cylinder is blocked. The tremie tube is lifted and collected while contacting the packing on the upper surface of the body so that water does not enter the inner cylinder.

[Embodiment] An embodiment of the present invention will be described below with reference to the drawings.

Numeral 1 is a tremie pipe for pouring improved soil in water. Reference numeral 2 denotes a hollow inner cylinder having an appropriate diameter, and a reverse cone-shaped closing body 3 having a diameter larger than the inner cylinder diameter is fixed to the lower end of the inner cylinder 2.
A discharge port 4 having an appropriate size is formed on the side wall of the upper inner cylinder 2 of the closing body 3. A funnel-shaped hopper 5 for feeding improved soil is attached to the upper part of the inner cylinder 2. Inside the inner cylinder 2, a screw 6 for forcibly feeding the improved soil charged from the hopper 5 downward is installed. The screw shaft 7 of the screw 6 has its lower end placed on the closing body 3, and is axially supported by a bearing 9 fixed to a support body 8 suspended while securing a space for improved soil feeding on the hopper 5. Further, the bearing of the motor base 10 whose upper end is placed and fixed on the support plate 8.
The shaft is supported by 11 and is connected to the drive shaft of an electric motor 12 fixed on the motor base 10 via a coupling 13. 14 is a stirring blade attached to the screw shaft 7 in the hopper 5,
The improved soil that temporarily stays in the hopper 5 is stirred to make it uniform.

Reference numeral 15 denotes an outer cylinder loosely fitted to the outer side of the inner cylinder 2, having a diameter slightly larger than that of the inner cylinder 2 and smaller than that of the closing body 3, and its length is substantially the same as that of the inner cylinder 2. . This outer cylinder 15 is the hopper 5.
It is suspended by connecting to the piston rod 18 of the cylinder 17 pivotally attached to the support material 16 fixed to the side wall of the cylinder 17.
When the piston rod 18 is extended, the lower end of the outer cylinder 15 contacts the upper surface of the closing body 3. Reference numeral 19 denotes a packing attached to the closing body 3, which keeps the outer cylinder 15 and the closing body 3 airtight to prevent water from entering.

Then, when the improved soil is cast on the bottom of the water, as shown in FIG. 2, the piston rod 18 of the cylinder 17 is extended to bring the lower end of the outer cylinder 15 and the closing body 3 into contact with each other so that the water inside the inner cylinder 2 is filled with water. To prevent it from intruding, and then suspend it by the crane on the ship and drop it into the water. Closure body 3 at the lower end of tremie tube 1
The descent will stop when it reaches the bottom of the water. At this time the outer cylinder
Inner cylinder 2 and outer cylinder so that the upper end of 15 is above the water surface
It is necessary to design 15 lengths in advance.

Subsequently, the electric motor 12 is driven and the screw 6 is rotated, and the improved soil produced by the mixing device on the ship is charged into the hopper 5 through the screw conveyor or the pressure feeding pipe. The fed improved soil is forcibly fed downward by the screw 6. When the inner cylinder 2 is filled with the improved soil, the piston rod 18 of the cylinder 17 is contracted to raise the outer cylinder 15 as shown in FIG. As the outer cylinder 15 rises, the discharge port 4 of the inner cylinder 2 is exposed, and the improved soil is extruded from the discharge port 4 and placed on the bottom of the water.

When the driving is completed, the piston rod 18 of the cylinder 17 is extended with the improved soil partially remaining in the inner cylinder 2 to extend the outer cylinder.
15 is lowered, the lower part is closed to prevent water from entering the inner cylinder 2, and then lifted and collected.

In the illustrated example, the tremie tube 2 is described as a single piece, but it is also possible to connect a plurality of divided pieces to form a tremie tube having a desired length. Further, although the cylinder 17 is adopted as the raising / lowering means of the outer cylinder 15, it is also possible to employ one that is driven up and down by an electric motor using a rack and pinion or the like.

[Advantages of the Invention] In the underwater casting tremie pipe according to the present invention, since the packing is attached along the outer peripheral portion of the upper surface of the closing body, the lower end of the outer cylinder and the closing body are moved when the tremie pipe is moved in water. Sealing with the upper surface can be facilitated and the degree of sealing can be improved, water can be reliably prevented from entering the inner cylinder from the lower end of the outer cylinder, and leakage of improved soil can be eliminated, thereby making It does not deteriorate the quality of the improved soil and does not pollute the water near the site.

In addition, by setting the outer cylinder to have the same length as the inner cylinder, the upper end of the outer cylinder can be exposed on the surface of the water to perform the casting work, and water can be prevented from entering from the upper end of the outer cylinder.

Further, the improved soil can be forcibly sent in by the screw 6, and the closing body at the lower end of the tremie pipe 2 has an inverted conical shape, so that the lower end of the tremie pipe 2 can be easily fixed to the water bottom at the time of driving, Tremie tube 2 driven by screw
It is possible to prevent fluctuation and efficiently place the improved soil.

[Brief description of drawings]

FIG. 1 is a partially longitudinal front view of a tremie pipe for underwater casting according to the present invention, and FIGS. 2 and 3 are partially longitudinal front views for explaining a use state. 1 ... Tremy tube, 2 ... inner cylinder, 3 ... closed body, 4 ...
Discharge port, 5 ... Hopper, 6 ... Screw, 7 ... Screw shaft, 12 ... Electric motor, 14 ... Stirring blade, 15 ... Outer cylinder, 17 ... Cylinder, 18 ... Piston rod

Claims (1)

[Scope of utility model registration request] 1. A discharge port is formed in a lower side wall of a hollow inner cylinder having a funnel-shaped hopper formed in an upper part thereof, and an inverted conical closing member having a diameter larger than the inner cylinder diameter is fixed to a lower end of the hollow inner cylinder. A packing is adhered to the upper surface of the closing body along the outer peripheral portion, a screw is provided inside the inner cylinder and is connected to a drive shaft of an electric motor mounted on a hopper, and an inner side is provided outside the inner cylinder. An outer cylinder having a length equal to that of the cylinder and freely movable up and down by the elevating means is loosely fitted, and when the outer cylinder descends, the lower end of the outer cylinder abuts the packing adhered to the upper surface of the closing body, and when ascending, A tremie pipe for underwater casting, characterized in that the discharge port of the cylindrical body is exposed to the outside.