JPH111938A - Underwater drilling rig - Google Patents

Abstract

(57) [Abstract] [Problem] When excavating earth and sand inside a steel pipe cell, work must be performed with sufficient care so that the clam cell does not contact the cut beam at the place where the cut beam is disposed densely. Therefore, it cannot be denied that the work efficiency is reduced. A trolley (10) that can freely move on a gantry (1) provided on the water surface, and a trolley (1) with its lower end facing underwater.
And a guide pipe 20 supported at 0 and tiltable in all directions in a horizontal plane, and suspended from above the carriage 10 and inserted through the guide pipe 20 to jet water from a jet nozzle 32 at a lower end projected into the water. An underwater drilling device including a jet pipe 30 for drilling earth and sand is employed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an underwater excavator for excavating earth and sand inside a steel pipe cell.

[0002]

2. Description of the Related Art A steel pipe cell is used as a foundation for a harbor structure, a pier, or the like, and is constructed by continuously casting steel pipes into a wall shape as a water stop wall. Then, the earth and sand inside the cell is excavated, and concrete is poured into the excavation hole to be used as a foundation.

[0003] Excavation methods inside the cell are roughly classified into the following two methods. First, as the first excavation method, excavation is performed with the water inside the cell drained and the excavation ground exposed.
Concrete is poured into the excavation hole to construct the foundation.
In this excavation method, it is necessary to strengthen the excavation ground in advance so that it can withstand water pressure and blow-up from below before excavation. Also,
With the lowering of the excavation surface, it is necessary to install one, two and three steps of cutting beams inside the cell in order to counter the soil water pressure outside the cell. This method has the advantage that the excavation work can be performed by exposing the excavation ground, so that the excavation of the confined section of the cutting beam and the removal of a large amount of soil attached to the steel pipe connection can be easily performed, and the excavation status can be easily checked. On the other hand, it is necessary to perform ground improvement and erection and removal of cutting beams, and there is a concern that the construction period will be prolonged and costs will rise.

[0004] As a second excavation method, underwater excavation is performed while water is stored in the cell, and underwater concrete is poured into the excavation hole to construct a foundation. This excavation method eliminates the need for large-scale ground improvement and erection of cutting beams due to a decrease in the excavated surface unlike the first method, making it possible to carry out construction economically with a short construction period and reduced costs. Become.

[0005]

According to the second excavation method,
Clam cells are used for underwater excavation, but work must be done with sufficient care so that clam cells do not contact the girder in places where the girder is overcrowded, so it is unavoidable that work efficiency will decrease . In addition, the diver dives into the water to remove the adhering soil at the steel pipe connection.This work is performed in muddy water. The work efficiency is low because it cannot be implemented due to unexpected reasons. Also, the diver's movements in the water are not monitored closely, and safety management cannot be performed sufficiently.

The present invention has been made in view of the above-mentioned circumstances, and when the second excavation method is implemented, underwater excavation work of an overcrowded section and a large amount of soil adhering to a steel pipe joint are safe. An object of the present invention is to provide an underwater excavator that can be removed reliably.

[0007]

In order to solve the above-mentioned problems, the following underwater excavator is employed. This underwater excavator includes a bogie that can freely move on a gantry provided on the water surface, a guide pipe that is supported by the bogie with the lower end facing the water, and that can be tilted in any direction in the horizontal plane, Is suspended from above and inserted through the guide pipe,
And a water injection pipe for excavating water by ejecting water from a lower end protruding into the water.

In this underwater excavator, a hole through which a guide pipe is inserted is provided in the bogie, and a spherical receiving seat is provided in an upper opening of the hole, and the guide pipe is inserted through the hole. By providing the spherical movable seat which is combined with the spherical receiving seat when the guide pipe is provided, the guide pipe is supported so as to be tiltable in all directions in the horizontal plane. Then, the water injection pipe inserted into the guide pipe is tilted in all directions together with the guide pipe, and a water stream is blown obliquely from above onto the excavation ground located immediately below the cut-off beam to excavate earth and sand.

Further, in this underwater excavator, a first movable body reciprocally movable in one horizontal direction is provided on a bogie, and a first movable body is provided on the bogie.
On the moving body, a second moving body that can reciprocate in another horizontal direction orthogonal to the moving direction of the first moving body and that supports the guide pipe at a position separated from the spherical movable seat is further mounted. The guide pipe can be inclined in any direction in the horizontal plane by moving the first moving body and the second moving body in arbitrary directions.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an underwater excavator according to the present invention will be described with reference to FIGS. The underwater excavator shown in FIGS. 1 and 2 has a trolley 10 movable on a gantry 1 installed on a girder, and is supported by the trolley 10 with its lower end facing underwater, and can be inclined in any direction in a horizontal plane. And a jet pipe (water injection pipe) 30 that is suspended from above the carriage 10 by a crane, inserted through the guide pipe 20, and ejects a water flow from a nozzle protruding into the water to excavate earth and sand. It has.

A wheel 11 provided on the trolley 10 can freely travel on the gantry 1 and is provided with a fixing mechanism (not shown) so that the trolley 10 can be stopped at a desired place.

A hole 12 through which a guide pipe 20 is inserted is vertically provided in the carriage 10, and a spherical receiving seat 13 is provided in an upper opening of the hole 12 around the axis of the hole 12. . On the other hand, the guide pipe 20 is provided with a spherical movable seat 21 substantially at the center in the length direction,
When the guide pipe 20 is inserted into the hole 12, the two are combined, and the guide pipe 20 is supported so as to be tiltable in any direction in the horizontal plane.

Further, on the carriage 10, a pair of slide tables 14 which are located above the spherical receiving seat 13 and are provided in one horizontal direction (hereinafter, referred to as X direction) are reciprocally movable. One slide block (first moving body) 15 is mounted, and on the first slide block 15,
A second slide block (second moving body) 16 is mounted so as to be able to reciprocate in another direction orthogonal to the X direction (hereinafter, referred to as a Y direction).

On the first slide block 15, a slide screw 17 arranged in the X direction and having a tip rotatably supported is screwed to a female screw block 17a fixed to the slide base 14 and installed. A slide handle 17b for rotating the slide screw 17 is attached to the base end. The slide screw 17 reciprocates the first slide block 15 in the X direction by operating a slide handle 17a. The same slide screw 18 is used for the second slide block 1.
6 is attached to the female screw block 18a fixed to the first slide block 15 in the Y direction. The second slide block 16 is moved in the Y direction by operating the slide handle 18b. It is designed to move back and forth.

The first and second slide blocks 15 and 16 are provided with holes 15c and 16c, respectively, through which the guide pipe 20 is inserted. The holes 15c and 16c are provided in the second slide block 16. Is provided with a guide support member 19 for supporting the upper end of the inserted guide pipe 20 from the periphery.

The guide pipe 20 is inserted into a hole 12 provided in the carriage 10 to move the spherical movable seat 21 to the spherical receiving seat 13.
, And the upper end thereof is inserted through the holes 15c and 16c provided in the first and second slide blocks 15 and 16, respectively.
By freely moving 16 in the X and Y directions, it is supported so as to be tiltable in any direction in the horizontal plane.

The jet pipe 30 is suspended by a crane (not shown) and inserted through the guide pipe 20. A jet pump 31 for supplying water under pressure is connected to an upper end of the jet pipe 30, and a jet nozzle 32 is attached to a lower end. The jet pump 31 is operated to generate a high-pressure jet water flow from the jet nozzle 32. It is possible.

An operation procedure for underwater excavation of the earth and sand inside the steel pipe cell using the underwater excavator constructed as described above will be described with reference to FIG. A plurality of cutting beams 3 are erected at the upper end of the water stop wall 2 that forms the cell and exposed above the water surface, and the gantry 1 on which the underwater excavator runs is installed on these cutting beams 3.

(1) On the gantry 1, an underwater excavator is set slightly above the girder 3 and shifted laterally. At this stage, the jet pipe 30 is not mounted on the guide pipe 20. (2) The jet pipe 30 is hung by a crane and inserted into the guide pipe 20. (3) The lower end of the jet pipe 30 is lowered to the excavation position, and the vertical position of the jet nozzle 32 is determined. (4) The first and second slide blocks 15 and 16 are moved, the jet pipe 30 is inclined together with the guide pipe 20, and the position of the jet nozzle 32 in the horizontal direction is determined. As a result, the jet pipe 30 is inclined, and the jet nozzle 32 is directed to the excavated ground 4 located immediately below the cutting beam 3 while avoiding the cutting beam 3. (5) The jet pump 31 is operated to create a jet stream, and the jet stream is blown obliquely from above onto the excavation ground 4 to loosen earth and sand and excavate. (6) The position of the jet nozzle 32 is horizontally moved while either the first or the second slide block 15 or 16 is moved to change the inclination angle of the guide pipe 20, thereby expanding the excavation range. (7) While the excavated soil is pushed to the place where the cutting beam 3 is not overcrowded by the jet water flow, the excavated earth is excavated by the clam cell 5 at the same time. In addition,
Underwater excavation is performed using a clam cell 5 in a place where the cutting beam 3 is not overcrowded as before.

By excavating the soil inside the steel pipe cell underwater in the manner described above, it is possible to excavate the earth and sand located immediately below the girder 3, and to efficiently perform the underwater excavation even in a dense place of the girder 3. can do.

In particular, in this underwater excavator, by combining the spherical receiving seat 13 provided on the bogie 10 and the movable spherical seat 21 provided on the guide pipe 20, the jet pipe 30 inserted through the guide pipe 20 can be submerged. It can be tiltably supported in any direction in the plane, so that the beam 3
The jet water stream can be sprayed obliquely from above the excavated ground located just below the excavated ground, avoiding the cutting beams 3.

Further, the first slide block 15 which can reciprocate in the X direction and the second slide block 16 which can reciprocate in the Y direction orthogonal to the X direction are respectively moved in arbitrary directions, so that the guide pipe is moved. The jet pipe 30 inserted through 20 can be inclined in any direction in the horizontal plane.

When removing the soil attached to the connecting portions of the steel pipes forming the water blocking wall 2, the jet water flow is directed to the connecting portions of the steel pipes in the same manner as described above, and the adhering soil is washed away by the jet water flow. do it. Therefore, it is possible to perform the clam cell excavation on the other side while performing the adhering soil removal operation on the one hand, and it is possible to significantly improve the work efficiency. In addition, safety can be improved by mechanizing work that relies on divers.

[0024]

As described above, according to the underwater digging apparatus of the present invention, the water jet pipe is inclined and its tip is directed obliquely from above toward the digging ground located immediately below the girder. By excavating by excavating earth and sand, excavated earth and sand located immediately below the girder can be excavated, and underwater excavation can be efficiently performed even in a dense portion of the girder.

In the same manner, it is possible to remove the adhering soil at the steel pipe connection portion by directing the jet water flow toward the steel pipe connection portion so that the adhering soil is washed away by the jet water flow.
The clam cell excavation can be performed simultaneously with the adhering soil removal work on the other side, so that not only the work efficiency can be remarkably improved, but also safety can be improved by mechanizing the work that relied on the diver.

Further, a hole through which the guide pipe is inserted is provided in the bogie, and a spherical receiving seat is provided in an upper opening of the hole. The guide pipe is provided with a spherical receiving seat when the guide pipe is inserted into the hole. By providing the combined spherical movable seat, the water injection pipe inserted into the guide pipe can be supported with the guide pipe so as to be tiltable, thereby avoiding the cut beam and obliquely above the excavated ground located directly below it. Water stream can be sprayed.

Further, a first moving body reciprocally movable in one horizontal direction is provided on a carriage, and a first moving body is provided on the first moving body in another horizontal direction orthogonal to the moving direction of the first moving body. A second movable body that supports the guide pipe at a position away from the spherical movable seat, and moves the first movable body and the second movable body in arbitrary directions.
The water injection pipe inserted into the guide pipe can be inclined in any direction in the horizontal plane.

[Brief description of the drawings]

FIG. 1 is a side view showing an embodiment of an underwater excavator according to the present invention.

FIG. 2 is a sectional view taken along line II-II in FIG.

FIG. 3 is a state explanatory view showing an operation of excavating earth and sand inside a steel pipe cell underwater using the underwater excavator of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 gantry 3 cutting beam 10 carriage 13 spherical receiving seat 15 first slide block (first moving body) 16 second slide block (second moving body) 20 guide pipe 21 spherical movable seat 30 jet pipe (water injection pipe)

Claims (3)

[Claims] An underwater excavation device for excavating earth and sand inside a cell formed by being partitioned by a water stop wall, comprising: a bogie freely movable on a gantry provided on the water surface; A guide pipe supported on the trolley in a state facing the trolley and capable of inclining in any direction in the horizontal plane; and a water pipe is hung from above the trolley and inserted into the guide pipe, and ejects water from the lower end protruding into the water. An underwater excavator comprising: a water injection pipe for excavating earth and sand. 2. The underwater excavator according to claim 1, wherein the bogie has a hole through which the guide pipe is inserted, and an upper opening of the hole has a spherical seat. The guide pipe is characterized by being provided with a spherical movable seat that is combined with the spherical receiving seat when the guide pipe is inserted into the hole and that can tilt the guide pipe in any direction in the horizontal plane. Underwater drilling rig. 3. The underwater excavator according to claim 1, wherein a first movable body that can reciprocate in one horizontal direction is provided on the bogie, and the first movable body is provided on the first movable body. Is reciprocally movable in another horizontal direction orthogonal to the moving direction of the first moving body, further supports the guide pipe at a position separated from the spherical movable seat, and is combined with the first moving body. An underwater excavator, comprising: a second movable body that moves the guide pipe in all directions in a horizontal plane by moving the guide pipe.