JP3404591B2 - Two-shaft deep mixing apparatus and method for detecting and controlling penetration of underground stirring shaft during construction by the apparatus - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a biaxial type deep layer mixing treatment apparatus and a method of detecting and controlling a state of penetration of an agitating shaft in the ground by the apparatus.

[0002]

2. Description of the Related Art When the agitating shaft of a two-axis type deep-mixing processing apparatus is penetrated into the ground, it is conventional to change the rotating direction of the agitating shaft for each depth in order to ensure vertical penetration of the agitating shaft. Although known (see Japanese Patent Laid-Open No. 8-144264),
This known technique does not detect the underground penetration state of the stirring shaft,
Further, there is a problem in that only the inclination of the stirring shaft in the front-back direction is controlled.

[0003]

SUMMARY OF THE INVENTION The problem to be solved by the present invention is to solve the above-mentioned problems of the prior art and to have a function of controlling so that the underground penetration of the agitation shaft is properly performed as a whole. Another object of the present invention is to provide a two-axis type deep layer mixing treatment apparatus, and at the same time, to provide a concrete detection method and an effective control method of the underground penetration state of the stirring shaft when the apparatus is installed.

[0004]

In order to solve the above-mentioned problems, the apparatus and method of the present invention are as follows respectively. In the present invention, the agitation shaft simply means a unitary agitation shaft assembly. .

First, in the first biaxial type deep layer mixing processing apparatus of the present invention, a biaxial type deep layer mixing processing apparatus is constructed by vertically arranging a pair of left and right unit agitation shafts on a drive unit which is elevated by being guided by a reader. In the leader, the leader inclinometer and two or more G
The PS antenna is attached, the agitation shaft inclinometer and the agitation shaft torsion meter are attached to the agitation shaft, and the agitation shaft guide device that is vertically movable on the reader and detachable from the agitation shaft is attached to the lower part of the reader.

In the second biaxial type deep layer mixing processing apparatus of the present invention, a telescopic tip pick is attached to each tip of the unit stirring shaft in the first apparatus.

Next, in the method for detecting the penetration state of the stirring shaft in the ground of the present invention, the X of the leader measured by the reader inclinometer in the ground penetration process of the stirring shaft when the construction is carried out by either of the above-mentioned two devices. , Y-direction inclination angle and position information obtained by the GPS antenna, the displacement of the upper end of the stirring shaft in both X and Y directions due to the inclination of the reader is calculated, and the stirring shaft tilt meter measures the stirring shaft tilt angle. Based on the inclination angles in both the X and Y directions, the X of the lower end of the stirring shaft due to the inclination of the stirring shaft,
The displacements in both the Y and Y directions are calculated, and the sum of these displacements is used to determine the displacements in both the X and Y directions from the reference point of the tip of the stirring shaft at an arbitrary depth.

The above-mentioned detection method assumes that the agitation shaft does not bend during underground penetration (that is, the inclination direction of the tip of the agitation shaft is not the same as the penetration direction, and the agitation shaft slides sideways into the ground). It has been confirmed by experiments that this assumption fits the actual situation.

Next, in the first method for controlling the penetration state of the stirring shaft in the ground according to the present invention, when the displacement in the Y direction (front-back direction) obtained by the detection method reaches a predetermined value, the unit stirring shaft The tip of the stirring shaft is slid in the opposite direction by reversing the rotation direction so that the displacement of the tip of the stirring shaft in the Y direction falls within the allowable range.

In this control method, at the time of implementation,
It is preferable to discharge a proper amount of water from the ground improvement material discharge hole provided at the tip of the stirring shaft to promote the slip of the tip of the stirring shaft.

Next, in the second method for controlling the underground penetration state of the stirring shaft of the present invention, the leader is moved in the X direction (left and right direction) in the initial stage of the underground penetration of the stirring shaft when the apparatus is installed.
In addition, the stirring shaft guide device holds the stirring shaft and holds the stirring shaft so as to suppress the movement in the X direction.

Next, in the third method for controlling the penetration state of the stirring shaft into the ground according to the present invention, when the displacement in the X direction obtained by the detection method reaches a predetermined value, the stirring shaft guide device temporarily operates. The stirring shaft is held and its movement in the X direction is suppressed.

Next, in the fourth method for controlling the underground penetration state of the stirring shaft according to the present invention, the stirring detected by the stirring shaft torsion meter in the underground penetration step of the stirring shaft when the construction is carried out by the first device. When the twist angle of the shaft reaches a predetermined value, twist the tip of this unit stirring shaft while discharging a suitable amount of liquid such as water from the ground improvement material discharge nozzle provided at the tip of one unit stirring shaft. It is slid in the direction that the angle becomes smaller so that the twist angle is within the allowable range.

Next, in the fifth method for controlling the underground penetration state of the agitation shaft according to the present invention, the agitation detected by the agitation shaft torsion meter in the underground penetration step of the agitation shaft when the construction is carried out by the second device. When the twist angle of the shaft reaches a predetermined value, the tip pit of one unit stirring shaft is extended to suppress slippage of the tip of this unit stirring shaft, and in this state, the tip of the other unit stirring shaft is twisted. Is slid in such a way that the angle becomes smaller so that the twist angle is within the allowable range.

In this method, at the time of carrying out the method, a proper amount of water is discharged from the ground improvement material discharge hole provided at the tip of the unit agitating shaft to be slid so that the tip of the unit agitating shaft is slipped. It is preferable to promote it.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, a biaxial type deep layer mixing processing apparatus of the present invention will be described with reference to FIGS. 1 to 5. A leader 2 is erected on the front part, and a pair of left and right unit agitation shafts 4, 4'is attached to a drive unit 3 which is guided by the leader 2 and moves up and down.
The unit agitating shafts 4 and 4 ′ are provided with a plurality of stages of agitating blades 5 at the lower end portions thereof, and a ground improvement material discharge nozzle 6 is provided.

The unit stirring shafts 4 and 4'are integrally connected by a plurality of stages of spacing members, and hereinafter, the united stirring shafts 4 and 4'are collectively referred to as the stirring shaft 7.

The apparatus of the present invention is different from the conventional apparatus in that it has a structure useful for detecting and controlling the underground penetration state of the stirring shaft 7, and the structure useful for the detection is as follows. The reader inclinometer 8 and the GPS antenna 9 are attached to the reader 2, and the stirring shaft inclinometer 10 is attached to the stirring shaft 7.
And a stirring shaft torsion meter 11 are attached, and as a configuration useful for control, a stirring shaft guide device 12 is attached to the lower part of the reader 2 and a tip pick 13 is attached to the unit stirring shafts 4 and 4'as needed. It is attached.

For the reader inclinometer 8 and the stirring axis inclinometer 10, for example, a pair of servo accelerometers are used, respectively.
The inclination angle of the reader 2 and the stirring shaft 7 with respect to the Z direction (vertical direction) can be decomposed into the X direction and the Y direction for measurement, and the stirring shaft torsion meter 11 is, for example, an optical angle measuring sensor. Using a gyro, the twist angle of the stirring shaft 7 with respect to the X axis can be measured.

In the case of the figure, the stirring shaft inclinometer 10 and the stirring shaft torsion meter 11 are provided above the stirring blade 5 and on the spacing member 14 connecting the left and right unit stirring shafts 4, 4 '.
Since these enter the ground, it is desirable to install them in a waterproof case, but the stirring axis inclinometer 10 may be installed above the illustrated position.

The position of the GPS antenna 9 to be installed in two or more units is tentatively arbitrary, but in the case of the figure, it is installed on the top sheave device 15 of the reader 2.

The stirring shaft guide device 12 is provided below the reader 2 by a wire (not shown) and can be lifted and lowered along the reader 2 and can be engaged with and disengaged from the stirring shaft 7. When the stirring shaft 7 is engaged, it is securely held so as not to roll laterally.

A stirring shaft guide device 1 illustrated in FIGS. 4 and 5.
2, the pair of left and right holders 16 and 16 respectively hold the unit stirring shafts 4 and 4'in the front-rear direction, and in the figure, 17 is a hydraulic cylinder for moving the holder 16 and 18 is a holder. Reference numeral 19 denotes a ball bearing provided on the arc-shaped inner surface of 16, and 19 denotes a guide provided on the leader 2.

The tip pick 13 may be configured as a piston rod of a hydraulic cylinder 20 provided inside the tip of the unit stirring shaft 4, as shown in FIG.

Next, referring to FIG. 6, the method for detecting the state of penetration of the stirring shaft into the ground according to the present invention will be described. In FIG. 6, a vertical central axis of the stirring shaft when the leader 2 is in a vertical state at point A is shown in FIG. The position of the intersection between the top sheave device 15 and the top sheave device 15 is also the position of the upper end of the stirring shaft 7, and when these positions penetrate the stirring shaft 7 to the depth Z ′, they are tilted by the leader 2 respectively. If the inclination angle of the leader 2 in the Y direction (front-back direction) measured by the leader inclinometer 8 at this time is α, then the leader 2
The displacement M in the Y direction (front-back direction) of the upper end of the stirring shaft 7 due to the inclination of is calculated by the following equation.

## EQU1 ## M = (Y ₁ −Y ₀ ) −L × sin α Y ₀ : Y coordinate Y _{1 of} point A detected by GPS 9: Y coordinate of point A ′ L: distance between points A and B

If the inclination angle of the stirring shaft 7 in the Y direction (front-back direction) measured by the stirring shaft inclinometer 10 at this time is β, the tip end is displaced in the Y direction (front-back direction) by the inclination of the stirring shaft 7. N is calculated by the following equation.

## EQU00002 ## N = L'.times.sin .beta. L ': distance between points B and C

In FIG. 6, the point C is the position (reference position) of the tip of the agitation shaft 7 when the agitation shaft 7 is penetrated to the depth Z ′ without tilting the agitation shaft 7 along the reader 2 in the vertical posture. Let 'be the actual position of the tip of the stirring shaft 7,
Displacement of the tip of the stirring shaft 7 at the depth Z '(point C, point C'
It is clear from the figure that the distance) is calculated by the sum of the displacement M and the displacement N.

Since the detection of the displacement of the tip of the stirring shaft 7 in the X direction (horizontal direction) is the same as in the case of the Y direction described above, the description thereof will be omitted.

Next, the first method of controlling the penetration state of the stirring shaft into the ground according to the present invention will be explained.
As described in Japanese Patent No. H264, Y of the stirring shaft 7
The inclination in the direction (front-back direction) is mainly caused by the rotation of the pair of left and right unit stirring shafts 4, 4 '.

Assuming that the upper side of FIG. 7 is the front side as seen from the apparatus main body 1, as shown in the figure, the unit stirring shaft 4 on the left side is facing forward and the unit stirring shaft 4'on the right side is clockwise.
Are rotated counterclockwise (this rotation is referred to as forward rotation), and the stirring shaft 7 tends to incline in the direction of arrow P at the rear (close to the apparatus main body 1).

Therefore, when the displacement in the Y direction (front-back direction) of the tip of the stirring shaft 7 detected by the above-described detection method reaches a predetermined value, the rotation direction of the unit stirring shafts 4, 4'is changed from positive to reverse. In this case, the tip of the stirring shaft 7 is slid in the opposite direction (in front of the apparatus main body 1).

The above-mentioned detection result is processed by the computer and displayed on the control screen as shown in FIG. 8, but the rotation direction of the unit stirring shafts 4 and 4'is switched by the tip of the stirring shaft 7. It is preferable that the displacement in the Y direction reaches the control line F before reaching the allowable line E in FIG.

When the tip of the stirring shaft 7 is moved, a proper amount of liquid such as water is discharged from the ground improvement material discharge nozzle 6 at the tip of each unit stirring shaft 4, 4 ′. Sliding is promoted, and movement can be performed smoothly.

Next, the second and third methods for controlling the penetration state of the stirring shaft into the ground according to the present invention relate to the control of the inclination of the stirring shaft 7 in the X direction (horizontal direction). There is a tendency for penetrating while maintaining the initial inclination, and this tendency is particularly strong in the X direction.

Therefore, in the initial stage of the penetration of the stirring shaft 7 into the ground, the left and right inclinations of the leader 2 are adjusted to 0, and the stirring shaft guide device 12 is engaged with the stirring shaft 7 so that the stirring shaft 7 is engaged. Suppress the lateral movement of the.

When the penetration direction of the stirring shaft 7 is determined, the stirring shaft guide device 12 is removed from the stirring shaft 7. After that, for example, the tip of the unit stirring shaft 4 (or 4 ') on one side is hard. When hitting something, the stirring shaft 7
However, in that case, when the displacement of the tip of the stirring shaft 7 in the X direction (horizontal direction) detected by the above-mentioned detection method reaches a predetermined value, the stirring shaft 7 is again guided to the stirring shaft 7. The device 12 is engaged to temporarily suppress the lateral movement of the stirring shaft 7.

Next, referring to FIG. 9, a fourth method for controlling the penetration state of the stirring shaft in the ground according to the present invention will be described.
γ is the twist angle of the stirring shaft 7, and if the twist angle γ measured by the stirring shaft twist meter 11 reaches a predetermined value, it is controlled as follows.

An appropriate amount of liquid such as water is discharged from the ground improvement material discharge nozzle 6 provided at the tip of one unit stirring shaft 4'to make the tip of this unit stirring shaft 4'slippery. In this state, the rotation direction of the unit stirring shafts 4 and 4'is properly selected (in the case shown, the rotation is forward rotation), and the unit stirring shafts 4 '
Slide the tip of in the direction of arrow Q so that the twist angle γ becomes zero.

Next, in the fifth method for controlling the penetration state of the stirring shaft in the ground of the present invention, for example, the tip pick 13 of one unit stirring shaft 4 in FIG. Anchor so as not to slip, and in this state, appropriately select the rotation direction of the unit stirring shafts 4 and 4 '(in the case of the figure, it is set to forward rotation), and the tip of the other unit stirring shaft 4'in the direction of arrow Q. Slide it so that the twist angle γ becomes zero.

At this time, if a suitable amount of liquid such as water is discharged from the ground improvement material discharge nozzle 6 at the tip of the unit stirring shaft 4 ', the tip of the unit stirring shaft 4'will slip better, and the twist angle will be easier. Can be zero.

When the twisting of the stirring shaft 7 is corrected as described above, a displacement of the stirring shaft 7 in the Y direction occurs, but this displacement is eliminated by the above-mentioned first method of controlling the underground penetration state of the stirring shaft 7. Just do it.

[Brief description of drawings]

FIG. 1 is an overall side view of an example of a biaxial deep layer mixing processing apparatus of the present invention.

FIG. 2 is a front view of a lower portion of a stirring shaft in the biaxial type deep layer mixing processing apparatus of the present invention.

FIG. 3 is a cross-sectional view showing an installation mode of a tip pick in the second biaxial type deep layer mixing processing apparatus of the present invention.

FIG. 4 is a plan view of an example of a stirring shaft guide device in the biaxial type deep layer mixing processing device of the present invention.

5 is a front view of a holder in the stirring shaft guide device shown in FIG.

FIG. 6 is an explanatory diagram of a method for detecting a ground penetration state of a stirring shaft according to the present invention.

FIG. 7 is an explanatory diagram regarding a tilting direction of the stirring shaft in the first method for controlling the penetration state of the stirring shaft into the ground according to the present invention.

FIG. 8 is a control screen in a first method for controlling a ground penetration state of a stirring shaft according to the present invention.

FIG. 9 is an explanatory view of the fourth and fifth stirring shaft underground penetration control methods of the present invention.

[Explanation of Codes] 1: Device body, 2: Reader, 3: Drive unit, 4: Unit stirring shaft, 4 ': Unit stirring shaft, 5: Stirring blade, 6: Ground improvement material discharge nozzle, 7: Stirring shaft, 8: Leader inclinometer, 9: G
PS antenna, 10: stirring axis inclinometer, 11: stirring axis twist meter, 12: stirring axis guide device, 13: tip pick, 1
4: spacing member, 15: top sheave device, 16: holder, 17: hydraulic cylinder, 18: ball bearing,
19: Guide.

─────────────────────────────────────────────────── --- Continuation of the front page (56) References JP-A-7-42147 (JP, A) JP-A-8-144264 (JP, A) JP-A-60-102415 (JP, A) JP-A-60- 65816 (JP, A) JP 60-233223 (JP, A) JP 53-26410 (JP, A) JP 60-188521 (JP, A) Actually developed 62-72345 (JP, U) (58) Fields surveyed (Int.Cl. ⁷ , DB name) E02D 3/12 102

Claims (10)

(57) [Claims] 1. A two-axis deep-mixing processing apparatus comprising a pair of left and right unit agitation shafts vertically installed on a drive unit that is guided up and down by a reader, and the reader includes a reader inclinometer and two or more GPS antennas. In addition to the mounting, a stirring shaft inclinometer and a stirring shaft torsion meter are attached to the stirring shaft, and a stirring shaft guide device that is movable up and down on the reader and detachable from the stirring shaft is attached to the lower part of the reader. Axial type deep mixing processing equipment. 2. The biaxial type deep layer mixing processing apparatus according to claim 1, wherein a telescopic tip pick is attached to each tip of the unit stirring shaft. 3. A process according to claim 1 or Oite underground penetration step of agitating shaft when applied by apparatus according to claim 2, X leader measured by reader inclinometer, Y directions of inclination and GP
Based on the position information obtained by the S antenna, the displacement of the upper end of the stirring shaft in both the X and Y directions due to the inclination of the reader is calculated, and the X, Y of the stirring shaft measured by the stirring shaft inclinometer is calculated.
The displacements of the lower end of the stirring shaft in both X and Y directions due to the inclination of the stirring shaft are calculated based on the inclination angles of both Y directions, and the displacement in both X and Y directions from the reference point of the tip of the stirring shaft at an arbitrary depth is calculated by the sum of these displacements. A method for detecting the state of penetration of a stirring shaft into the ground. 4. When the displacement in the Y direction (front-back direction) obtained by the method according to claim 3 reaches a predetermined value, the rotation direction of the unit stirring shaft is reversed and the tip of the stirring shaft is slid in the opposite direction. hand,
A method for controlling a ground penetration state of a stirring shaft, wherein the displacement of the tip of the stirring shaft in the Y direction is set within an allowable range. 5. The ground of the stirring shaft according to claim 4, wherein a proper amount of liquid such as water is discharged from a ground improvement material discharge nozzle provided at the tip of each unit stirring shaft to promote sliding of the tip of the stirring shaft. How to control the penetration state. 6. The stirrer shaft guide is set so that the leader is not tilted in the X direction (horizontal direction) at the initial stage of penetration of the stirrer shaft into the ground when the apparatus is installed with the device according to claim 1 or 2. Hold the stirring shaft in the device and
A method for controlling a state of penetration of a stirring shaft in the ground, which is characterized by suppressing a directional movement. 7. When the displacement in the X direction obtained by the method of claim 3 reaches a predetermined value, the stirring shaft is temporarily held by the stirring shaft guide device to suppress the movement in the X direction. A method for controlling the state of penetration of a stirring shaft into the ground. 8. The unit agitation of one unit at the stage when the twist angle of the agitation shaft detected by the agitation shaft helix meter reaches a predetermined value in the underground penetration process of the agitation shaft when the apparatus is installed by the device according to claim 1. While discharging a suitable amount of liquid such as water from the ground improvement material discharge nozzle provided at the tip of the shaft, slide the tip of this unit stirring shaft in the direction in which the twist angle decreases to keep the twist angle within the allowable range. A method for controlling a ground penetration state of a stirring shaft. 9. The unit agitation of one unit at a stage when the torsion angle of the agitation shaft detected by the agitation shaft helix meter reaches a predetermined value in the underground penetration step of the agitation shaft when the apparatus is installed by the apparatus according to claim 2. The tip pit of the shaft is extended to suppress the slip of the tip of this unit stirring shaft, and in this state, slide the tip of the other unit stirring shaft in the direction in which the twist angle decreases so that the twist angle falls within the allowable range. A method for controlling the state of penetration of a stirring shaft in the ground. 10. The slipping of the tip of the unit agitation shaft is promoted by discharging an appropriate amount of liquid such as water from a ground improvement material discharge nozzle provided at the tip of the unit agitation shaft to be slid. The method for controlling the state of penetration of the stirring shaft in the ground.