JPS61196015A - Soft ground improving device - Google Patents

Abstract

PURPOSE:To enable improvement of stability and to facilitate maintenance of a device, by a method wherein driving devices for rotation of an agitating shaft and elevating are located to the lower part of a leader erected on a device body to lower the center of gravity of a whole device. CONSTITUTION:A distance between elevating frames 52a and 52b is decreased through expansion of hydraulic cylinders 51a and 51b for elevating, an agitating shaft 30 is grasped by a chuck mechanism 60b, and a chuck mechanism 60a is released. With the cylinder 51b contracted, the elevating frame 52b is lowered, the agitating shaft 30 is lowered as it is rotated, and the elevating frame 52a is raised. The agitating shaft 30 is grasped by a chuck mechanism 60a, and the chuck mechanism 60b is released. With the cylinder 51a expanded, the elevating frame 52a is lowered, the agitating shaft 30 is lowered as it is rotated, and the elevating frame 52b is raised. Further, the agitating shaft 30 is grasped by means of the chuck mechanism 60b, and after the chuck mechanism 60a is released, the agitating shaft 30 is lowered by following the similar procedures described above, and the agitating shaft 36 is penetrated into a soft ground.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a soft ground improvement device for improving soft ground on the ocean floor, on land, etc., and in particular, to an apparatus that improves the rotation and lifting means of a stirring shaft. It is.

(Prior Art) Conventionally, as a construction method for improving soft ground on the seabed or on land, as shown in Figs. The stirring blade 6 provided at the lower end of the stirring shaft 3 is penetrated into the soft ground to a predetermined depth by being lowered by a winch 5 or the like while being rotated by the rotary drive device 4 provided, and then pulled out. In one process, the ground improvement material is stirred using the stirring shaft 3.
The improvement material is fed by air pressure to the improvement material supply passage provided in the stirring shaft 3, and is discharged into the soft ground from the discharge port provided at the lower end of the stirring shaft 3. A jet that improves soft ground by stirring and mixing the ground improvement material and soft ground soil using the stirring blade 6! The mixing method (DJM method) is known.

However, in conventional soft ground improvement equipment, the rotation drive device 4 of the stirring shaft 3 and the winch 5 for lifting and lowering the stirring shaft 3 are connected to the stirring shaft 3.
Since it is provided at the upper end and the upper end of the leader 2, the center of gravity becomes high, making the entire device unstable. For this reason, there is a limit to the height hl of the leader 2, and the overall length h2 of the stirring shaft 3 has to be shortened, resulting in a shallow improvement depth. Since it acts on the entire length from the to the stirring blade 6 at the lower end, the stirring shaft 3 is likely to buckle, and to prevent this, an intermediate bearing 7 is required, and the leader 2 has a robust structure throughout. There is a need. In addition, since the rotation and lifting drive parts are located at the top, maintenance of the drive parts is difficult, and in the event of a breakdown, work must be done at height, which is not only dangerous, but also requires disassembly from below when replacing parts. There were various problems, such as in many cases not being possible.

(Objective of the Invention) In view of the above circumstances, the present invention is capable of improving stability by lowering the center of gravity of the entire device, increasing the height of the leader and the overall length of the stirring shaft, and deepening the depth of improvement. To provide a hanging device that can easily solve the problem of buckling of the stirring shaft, simplify the guiding structure of the stirring shaft, and perform maintenance safely and easily.

(Structure of the Invention) The present invention has a leader installed upright in the apparatus main body support a stirring shaft having a stirring blade at the tip so as to be rotatable and vertically movable.
At the bottom of the leader, there is a rotary drive device that transmits rotational torque to the stirring shaft while allowing the stirring shaft to move up and down, and a rotation drive device that alternately grips the stirring shaft and allows the stirring shaft to rotate while being gripped. Two sets of upper and lower chuck mechanisms that transmit lifting force,
This device is characterized by being equipped with an elevating drive device that moves the upper and lower chuck mechanisms up and down in opposite directions with predetermined strokes.

(Example) In FIGS. 1 and 2, 10 is an apparatus main body, which has a through hole 11 for raising and lowering a stirring shaft, and a leader 20 is erected above the through hole 11. The leader 20 consists of a lower main leader 21 and an upper auxiliary leader 22, and the main leader 21 is provided with a pair of upper and lower fixed frames 23 and 24. The main leader 21 is constructed to have a certain degree of strength and robustness in order to support the rotating and lifting drive part of the stirring shaft 30;
The ratio of the main leader 21 to the entire leader 20 is small (low), and the auxiliary leader 22 only guides the upper end of the stirring shaft 30, making the structure simple and lightweight. As a result, the overall leader 20 can be made lighter than the conventional boat, the total height Hl of the leader 20 can be increased, and the total length H2 of the stirring shaft 30 can be increased.

Note that the reader 20 may be provided on the device main body 10 via a trolley or the like so that its position can be changed back and forth, left and right.

As shown in FIGS. 3 to 5, the stirring shaft 30 is a two-piece structure consisting of an outer square pipe 31 of a predetermined length and an inner optical vibrator 32.
m construction, both pipes 31 and 32 are connected in the axial direction by a connecting member 33 to form a long length, and an improvement material supply passage 34 is formed that passes through the round pipe 32 and the connecting member 33 in the axial direction, Ground improvement material discharge port 35 and stirring 1 at the bottom end
36 are provided. The connection member 33 is the stirring shaft 30
chuck engaging grooves 37 are provided at a constant pitch in the axial direction of the connecting members 33, and chuck engaging grooves 37 are formed on the surfaces (four sides) of each connecting member 33,
As a result, the chuck engaging grooves 37 are formed at a constant pitch over the entire axial length of the stirring shaft 30.

The stirring shaft 30 is supported by the leader 20 so as to be rotatable and movable up and down. !
The upper end of the stirring shaft 30 is rotatably supported by a guide frame 25 via a swivel joint, etc. It is supported so that it can be raised and lowered.

The rotational drive device 40 for the stirring shaft 30 includes a drive motor 41 and a deceleration tlA 42, and is installed on the lower fixed frame 24 of the leader 20, and is configured to transmit rotational torque while allowing movement in the axial direction with respect to the stirring shaft 30. It has become.

Further, the lifting device 50 of the stirring shaft 30 is connected to the leader 2.
It is provided with a pair of upper and lower lifting frames 52a and 52b that are lowered four times by lifting hydraulic cylinders (air cylinders may be used) 51a and 51b provided on both fixed frames 23 and 24 of 0. Both cylinders 51a, 51b expand and contract with strokes corresponding to the axial pitch of the chuck engagement groove 37 provided in the stirring shaft 30. The upper and lower cylinders 51a, 51b are arranged in opposite directions, and the upper By simultaneously expanding and contracting the cylinder 51a and the lower cylinder 51b, the upper and lower lifting frames 52a and 52b are raised and lowered in opposite directions. Both elevating frames 52a, 52b are provided with chuck mechanisms 60a, 60b that removably grip the stirring shaft 30 and transmit the elevating force while allowing the stirring shaft 30 to rotate in each gripped state. .

Upper and lower lifting frames 52a, 52b and chuck mechanism 60a
, 60b have the same structure, and hereinafter, the upper lifting frame 52a
The structure of the chuck mechanism 60a will be explained in detail with reference to FIGS. 4 and 5. That is, the elevating frame 52a has guide rails 2 provided on the ladder 20 on both its left and right sides.
6 via guide rollers 53 so as to be movable up and down.

A support hole 54 is provided in the vertically penetrating frame 52a, and the rotary cylinder 61 is rotated through the support hole 54 via a support cylinder 55, a radial bearing 56, a thrust bearing 57, a sleeve 58, and a retaining member 59. Supported for free movement. The rotating cylindrical body 61 has a circular outer shape in cross section in order to be rotatably supported on the elevating frame 52a, and has a circular shape in cross section so that the stirring shaft 30 can be slidably inserted in the center thereof in the axial direction. A stirring shaft insertion hole 62 having a rectangular cross section corresponding to the outer shape is provided. 7 langes 63 at the upper end of the rotating cylinder 61
A chuck hydraulic cylinder (an air cylinder may also be used) 65 is attached to this 7-lunge 63 via a stand 64.
is attached, and a chuck claw 67 is connected to the piston 66 of the cylinder 65. As a result, the chuck claw 67 is provided so as to be able to move up and down integrally with the lifting frame 52a via the rotary cylinder 61 and the like, and to be rotatable relative to the lifting frame 52a. 64' is a reinforcing member.

In addition, the chuck claws 67 advance and retreat in the radial direction of the stirring shaft 30 by supplying and discharging pressure oil to the oil chambers 68 and 69 on both sides of the hydraulic cylinder 65, and removably engage with the chuck engagement groove 37 to stir. While holding the shaft 30 and rotating it together with the stirring shaft 30, the lifting force of the lifting frame 52a is applied to the stirring shaft 30.
It is designed to be transmitted to 71.72 is a pressure oil supply/discharge boat that connects the oil chamber 68°6 of the hydraulic cylinder 65 through oil passages 73, 74 provided in each of the above members and piping, etc.
9 is hydraulically connected to. Reference numerals 75 and 76 are oil supply ports for each bearing 56 and 57, and 77 is an oil seal.

When the soft ground improvement device configured as described above is used for improving soft ground on the seabed, the main body 10 of the device is a semi-submersible vessel, and this is equipped with a buoyancy adjustment means. The sunken ship) 10 can be adjusted to be floating on the sea, semi-submerged at an appropriate distance from the seabed, or bottomed on the seabed, and fixed to the seabed using appropriate fixing means. to be able to be fixed against the On the other hand, a support ship (not shown) which is W4 separately from the device main body 10 is equipped with an improved material supply device 1 for the stirring shaft 30, a power supply control M device for the rotation drive device 40, hydraulic cylinders 51a and 51b for lifting and a chuck. A hydraulic control device and the like for the hydraulic cylinder 65 are installed.

Then, while the main body 10 and the support boat are floating on the sea, they are transported to the ground improvement position by a tugboat (not shown) or by the propulsion device of the support boat, and at the ground improvement position, the main body 10 and the support boat are lifted up by the buoyancy adjustment means. The buoyancy of the device 10 is gradually reduced, the main body 10 of the device is held horizontally and gradually submerged, stopped at a predetermined distance from the seabed surface in a semi-submerged state, and fixed to the seabed surface by a fixing means.

Next, the stirring shaft 30 is rotated by the rotary drive device 40 and lowered by the lifting drive device 50, so that the stirring shaft 30 at the tip thereof is rotated and penetrates into the soft ground of the seabed.

This penetration step will be explained with reference to FIGS. 6(a) to 6(e).

(a) The upper and lower lifting hydraulic cylinders 518.51b are extended, the interval between the upper and lower lifting frames 52a and 52b is reduced, and the upper lifting frame 52a is held while the stirring shaft 30 is gripped by the chuck mechanism 60b of the lower lifting frame 52b. The chuck mechanism 608 is released.

The gripping of the stirring shaft 30 by the lower chuck mechanism 60b is achieved by supplying pressure oil to the head side oil chamber 68 of the chuck hydraulic cylinder 65 shown in FIG. 67 into the chuck engagement groove 37 of the stirring shaft 30. Furthermore, in order to release the upper chuck mechanism 608, pressure oil may be supplied to the rod-side oil chamber 69 of the chuck hydraulic cylinder 65 to cause the chuck claw 67 to retreat.

(b) With the stirring shaft 30 gripped by the lower chuck mechanism 60b, the lower lifting hydraulic cylinder 51b is retracted to lower the lower lifting frame 52b.
0 while rotating, and at the same time upper chuck Il! With the l mechanism 60a released, the upper lifting hydraulic cylinder 51a is retracted to raise the upper mu lowering frame 52a. At this time, the stirring shaft 30 is rotated by receiving rotational torque from the rotational drive device i40, but since the stirring shaft 30 is provided so as to be slidable in the axial direction with respect to the rotational drive device 40, the rotational drive device 40 does not interfere with the lowering of the stirring shaft 30. Further, as shown in FIG. 5, the lower chuck mechanism 60b is provided on the lower elevating frame 52b so as to be rotatable only via the rotary cylinder body 61's. It doesn't interfere with rotation. Therefore, the stirring shaft 30 is smoothly lowered while rotating.

(C) Lower the lower elevating frame 52b by a predetermined stroke sb, and lower the upper elevating frame 52a by a predetermined stroke Sa.
After raising the lower lifting frame 52a, contrary to the above (a),
Grip the stirring shaft 30 with the jack machine 11160a,
The chuck mechanism 60b of the lower elevating frame 52b is released. At this time, the stirring shaft 30 is continuously driven to rotate by the rotation drive device ff40. However, since the chuck mechanism 60a also rotates together with the stirring shaft 30 via the rotary cylinder 61, the chuck mechanism 608 can grip the stirring shaft 30 without any problem.

(d) With the stirring shaft 30 gripped by the upper chuck mechanism 608, extend the upper lifting hydraulic cylinder 51a and lower the upper lifting frame 52a, so that the stirring shaft 30 is rotated and integrated with the upper lifting frame 52a. At the same time, with the lower chuck mechanism 60b released, the lower lifting hydraulic cylinder 51b is extended to raise the F section lifting frame 52b. At this time, the upper chuck l
1i 160a is lowered together with the upper elevating frame 52a and the stirring shaft 30 while rotating integrally with the stirring shaft 30, and the lower chuck mechanism 60b rotates integrally with the stirring shaft 30 and does not interfere with the lowering of the stirring shaft 30. Lower lifting frame in condition 5
It is raised integrally with 2b.

(e) Lower the upper elevating frame 52a by a predetermined stroke Sa, and lower the lower elevating frame 52b by a predetermined stroke sb.
After raising the lower elevating frame 52b by
0b to grip the stirring shaft 30 and release the gooey mechanism 60a of the upper elevating frame 52a.

Thereafter, the stirring shaft 30 is lowered by repeating the steps (a) to (l) while rotating it.

While rotating the stirring shaft 30 by the rotary drive device W140, the upper and lower lifting frames 52a and 52b are moved to a predetermined stroke Sb by the respective lifting hydraulic cylinders 51a and 51b.
, Sa are repeatedly raised and lowered in opposite directions, and when the chuck mechanism 60a or 60b is raised, the chuck mechanism 60a or 60b is released and returned to the next gripping position, and when it is lowered, the chuck mechanism 60b or 6 is
By gripping the stirring shaft 30 by 0a, the stirring shaft 3
0 to the lower chuck mechanism 60b and the upper chuck mechanism 60a
While alternately gripping the lower lifting frame 52b or upper lifting frame 52a and lowering the strokes Sb and Sa integrally with each other, the stirring shaft 30 is lowered almost continuously, and the stirring shaft 9336 is rotated. Penetrates into soft ground.

In this way, after the stirring blade 36 is rotated and penetrated to a predetermined depth, the stirring I! Pull out while rotating 36 (
. At this time, the vertical lifting hydraulic cylinder 51
a, expand and contract 51b to the upper part.

The M descending frame 52a and the lower elevating frame 52b are repeatedly raised and lowered in opposite directions. However, during this pulling out, contrary to the above-mentioned penetration, the stirring shaft
0, and move the stirring shaft 30 integrally with the upper lifting frame 52a or the lower lifting frame 52b through predetermined strokes Sa, S.
When the elevating frame is lowered, the chuck mechanism 60
Release a or 60b and return to the next gripping position. As a result, the stirring shaft 30 is raised almost continuously while rotating and pulled out.

On the other hand, in either the process of penetrating or pulling out the stirring blades 36, the ground improvement material is pneumatically fed to the stirring shaft 30 via an improvement material supply hose or the like from an improvement material supply device installed on a support ship (not shown). supplying the improvement material to the improvement material supply passage 34 in the center, discharging the improvement material into the soft ground from the discharge port 35 at the lower end of the stirring shaft 30, and stirring the ground improvement material and the soft ground soil by the rotation of the stirring 1136, Mix it and improve soft ground.

By the way, in the above embodiment, the device main body 10 is a semi-submersible ship for improving soft ground on the seabed, but the device main body 10 is a work barge that is used while floating on the sea surface, and from above the sea surface, it is used to improve soft ground on the seabed. The ground may also be improved. Also,
The device of the invention can also be used on land. In this case, the base machine of a construction machine such as a crane is used as the main body of the device, and the stirring shaft 30 is supported by the leader system of a pile driver so as to be able to rise and fall freely, and the driving means for rotating and lifting the stirring shaft 30 is provided. The device of the present invention may be used as

Further, in the above embodiment, the outer cross-sectional shape of the stirring shaft 30 is a quadrangle, but it may be formed into a polygon other than a quadrangle, a drum shape, a circle, or the like. In addition, chuck mechanism aoa, 6
ob is not limited to being driven by a cylinder, but may be opened and closed by a screw, cam, motor, or the like. Also, the chuck mechanism 60a.

The 60b does not necessarily need to be rotated integrally with the stirring shaft 30, and may have any structure as long as it allows the stirring shaft 30 to rotate in the gripped state. Further, as a means for raising and lowering the chuck mechanisms 608 and 60b, a rotating screw is provided on the fixed frame 23.24, and the lifting frames 52a and 52b are screwed onto the rotating screw, so that the lifting frames 52a and 52b are raised and lowered by rotation of the rotating screw. Alternatively, the chuck mechanisms 60a, 60b may be raised and lowered by using the chuck mechanism 60a, 60b.

(Effects of the Invention) As described above, the present invention provides drive devices for rotating the stirring shaft and for lifting and lowering the stirring shaft, thereby lowering the center of gravity of the entire device and increasing its stability. can improve
Moreover, maintenance is easy and work is safe. Moreover, the structure of the upper part of the reader can be simplified, and
There is no need for a conventional intermediate bearing, making it possible to reduce weight and equipment costs. Furthermore, the depth of improvement can be deepened by increasing the height of the leader and the total length of the stirring shaft.

[Brief explanation of the drawing]

Fig. 1 is an overall side view showing an embodiment of the present invention, Fig. 2 is a front view thereof, Fig. 3 is a detailed view of the rotation of the stirring shaft and the elevating drive device, and Fig. 4 is IV-■ of Fig. 3. 5 is a sectional view taken along line v-v in FIG. 4, FIGS. 6(a) to 6(e) are explanatory diagrams showing the lowering process of the stirring shaft, and FIGS. 7 and 8 are conventional examples. FIG. 1 is a diagram corresponding to FIG. 1 and FIG. 10...VT device main body 20...Reader, 23.24
... Fixed frame, 30... Stirring shaft, 34... Improved material supply passage, 35... Discharge port, 36... Stirring blade,
37... Chirek engagement groove, 40... Rotation drive device,
50... Lifting drive device, 51a, 51b... Hydraulic cylinder for lifting, 52a, 52b... Lifting frame, 60a,
60b...Chuck mechanism, 61...Rotating cylinder body, 65
...Hydraulic cylinder for tilt, 67...Chuck jaw.

Claims (1)

[Claims] 1. A leader installed in the main body of the device supports a stirring shaft having a stirring blade at the tip so that it can rotate and be moved up and down, and the lower part of the leader transmits rotational torque to the stirring shaft while allowing the stirring shaft to move up and down. a rotation drive device that grips the stirring shaft alternately and transmits lifting force to the stirring shaft while allowing the stirring shaft to rotate in the gripped state; A soft ground improvement device characterized by being equipped with a lifting drive device that moves up and down in opposite directions.