JPS60246994A - Shield drilling method - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field of the Invention) The present invention relates to a shield M [regarding the advancement method, a tube 1fE is attached to 41F
Seal l” suitable for use in the Susumu construction method + 1 for the 11a method
Line up.

(Prior art) In the pipe propulsion method, a shield is generally installed at the forefront of the cleavage pipe, and the ground is perforated by the operation of a cutter installed on the shield, and the subsequent pier at the rear of the pipe is perforated. Actuation exerts thrust on the shield and tube, propelling them both into the excavated ground. The canter is spaced in front of the bulkhead across the interior of the shield, and when the shield and tube are propelled;
The excavated material scraped off by the canter is maintained in a state where the space is filled with the excavated material, and the excavated material causes the earth pressure generated by the reaction force from the partition wall to act on the ground face. This upper pressure and the earth pressure of the ground are balanced and the face is maintained stably.

(Problems to be Solved by the Invention) Conventionally, the excavated material rotates within the above-mentioned interval along with the rotation of the cutter, reaches a discharge means such as a screw conveyor provided at the lower part of the partition wall, and is discharged through this discharge means. ing. Therefore, a large frictional force acts between the object to be excavated and the partition wall, increasing the load on the cutter drive device. This tendency is particularly noticeable in sandy gravel ground, so when promoting sandy gravel ground using the mud pressure method, it is necessary to increase the turbidity of bentonite in the muddy water supplied to the face or increase the amount of mud. This reduces friction. However, it is difficult to dispose of muddy water after use, and it is not possible to reduce the frictional force with muddy water other than in the shape of a pressurized ball.

By the way, since the frictional force increases in proportion to the upper pressure of the ground, in order to reduce the frictional force, it is necessary to lower the pressure of the excavated object as much as possible. However, the -1 pressure limit of the ground is -1. Below the working pressure I: It'.

Since it is not possible to lower the frictional force, there is a limit to lowering the frictional force even in muddy water pressurization (IJ).

Another force, separate from the frictional force of the excavated object mentioned above, is the shield and subsequent force? The frictional force that acts between the 6 and the ground requires an extremely large force on the rocker.

Therefore, the first object of the present invention is to reduce the frictional force generated by rotating the excavated object with the canter within the interval between the bulkhead and the canter, or the friction that was exerted between the shield and the ground. The goal is to reduce power.

Another object of the present invention is to provide a propulsion force υ that can be applied to a wide range of ground ranging from soft ground to hard ground.

Still another object of the present invention is to provide a propulsion method that can be tuned to changes in the soil structure of the ground.

(Means for Solving the Problem) The shield propulsion method according to the present invention moves the JF dense head eccentrically in front of the partition wall provided across the shield body.
J! While moving and rotating, a thrust is applied to the shield body to move the shield body to Jl! ! It is propelled into the ground and detects the axial force acting on the vent from the ground or its excavated object.

When this detection (+ri) exceeds a predetermined value, the propulsion speed of the shield body is reduced or the eccentric movement speed of the piezoelectric head is increased.In another method, if the detected value exceeds a predetermined value, Decrease the lees advancing speed of the shield body and at the same time increase the eccentric slowing speed of the pressure punch and vent.

(Example) Examples of the present invention will be described below with reference to the drawings.

As shown in figure f51, the method of the present invention includes a shield main body 10
The piezoelectric head 14 provided in the front space 12 of the shield body IO is moved eccentrically and rotated, and exerts a force on the shield body IO during the eccentric movement of 1. Then, the axial force acting on the hole vent'l4 is detected.

Hole: The head 14 is located offset by e from the center of the shield wooden body 10, and is eccentrically linked to the shield body 10 and rotated by 111j. Moon - To Harm, F 1
When the excavated object 16 is eccentrically moved within the space 12 of the shield body 10, the excavated object 16 is sandwiched between the shield body IO and the piezoelectric head 14, and receives a single electric current. Further, when the piezoelectric hend 14 rotates, the frictional force when applying pressure to the excavated object is significantly reduced.

11) In order to produce a piezoelectric effect on the excavated object, a space surrounded by a cone surface of the front part of the shield body that gradually becomes smaller in diameter 11 toward the rear, or a space surrounded by a cone surface that gradually decreases in diameter 11 toward the rear, or a diameter 11 that is substantially the inner circumferential surface of the shield. Enclosed: A circular or truncated conical or circular positive electric hem; is eccentrically interlocked.

The part of the excavated object 16 to be consolidated is transferred to the piezoelectric element 21 and 14 by the eccentric arm 1iiJ, and moves to the circumferential force surface of the shield body 100.On the other hand, the shield body 10
Since it is moving forward under the force, t: / to the excavated object 16
+g is applied to the face 19 of the ground 18 as shown by arrow A, and this pressure is applied to the face 19 of the ground 18 to synchronize with the earth pressure of the ground and prevent the ground from collapsing. Due to the reaction force B of the Tonosho and the sequential movement of the parts in the circumferential direction, the excavated object 16 is sequentially pushed backward and consolidated 14 and the shield wooden cup 1
υ1 is taken out to the sliding chamber 22 through the gap 20 with 0. The excavated object 16 is then transported outside the mine.

The amount of υi of the excavated material 16 flowing into the shear chamber 22 is due to consolidation).
The higher the eccentric interlocking speed N of No. 14 is, the more likely it is. Moreover, this discharge φ is 1-pressure P generated in the excavated object 16 or 1°, 1°
There will be a lot more J. Therefore, the linear speed V of the shield body lO and the eccentric interlocking speed N of the consolidation hex I"l4 are -1
: Between J4' and P, the relational expression V=NPα holds true. Here, α is the ground seed wr
, is a coefficient determined by the particle size and other properties. If we rearrange this formula, we get:

P in the above equation is obtained by dividing the axial force acting on the piezoelectric head 14 by the effective cross-sectional area of 71'l4. This axial force varies because the coefficient α varies depending on the ground. Therefore, the axial force acting on the consolidation head 14 is detected, and the shield lees advancing speed is increased by 1. When the eccentric interlocking speed N of 71' 14 is lowered to the Geroka piezoelectric, and the detected value exceeds a predetermined value, the seal I/curving speed V is lowered or the eccentric movement speed N of 14 is lowered. By increasing the pressure, the upper pressure can be kept constant.

If the coefficient α fluctuates significantly, the shield propulsion speed V is increased until the detected value reaches a predetermined value, and at the same time the eccentric movement speed N of the consolidation head 14 is decreased. The eccentric movement speed N of the piezoelectric head 14 is simultaneously decreased by decreasing the linear velocity V.

Due to the eccentric movement of the piezoelectric head 14, the piezoelectrically-electrified portion of the object 16 to be excavated moves sequentially in the circumferential direction. As a result of the pressure movement, the excavated object 16 itself is pushed out linearly in the axial direction of the seal I/main body 10 without rotating in the circumferential direction.In this case, the excavated object 16 is pushed out into the sliding chamber 22. 1, j1 The output effect increases as the top pressure increases, so it brings about the exact opposite result from the conventional method of extracting the excavated object while rotating it with force and rotation.

In the example shown in FIG. Apply a force to the 24th part of the shield. Then, apply pressure to the head 26 and detect the force.

I26 is offset by e from the center of the shield main body 24, and a part of its outer circumferential surface is large enough to protrude from the shield cup 24 in the radial direction. Nor: 5. The hole vent 26 is sealed] - It is eccentrically interlocked with the wooden cup 24 and rotated at the same time. 1
To 1st density, l' 26 or +iij of shield body 24
When the force is eccentrically linked and rotated, the ground 28 around the 71' 26 is consolidated and the shield body 24 is propelled to this piezoelectric part, so the shield body 24
The frictional force acting between the ground and the ground a28 becomes smaller.

The axial force acting on the consolidation head 26 is detected, and this detection (1/i
Based on the above, perform the rotation operation.

FIG. 3 shows a shield propulsion device 30 that implements the shield propulsion method according to the present invention. At the front of the shield body 32, there is a cone surface 3 that gradually decreases in diameter by 11 toward the rear.
4 is provided, and Z-111 surrounded by this cone surface 34
136, seven threads 38 are arranged around +1140 with their axis offset by e from the axis of the shaft 40. Shield body 3 behind cone t+fi 34
A partition wall 42 is provided across the two.

The itl+ 40 is supported by two roller bearings 46 disposed on the casing 44 behind the bulkhead 42, and on a roller bearing 50 disposed on the bearing portion 49 of the rib 48 in front of the space 36. ing.

The eccentric sleeve 52 disposed around the old man 140 has an eccentric portion 54 having a circular outer shape and a +11 portion 55 extending rearward from the eccentric portion. The eccentric portion 54 has a hole located at a position eccentric from the center of the circle by an amount e. This hole extends into the shaft portion 55 and aligns its axis with the center of the circle. The shaft portion 55 projects rearwardly through a rolling bearing 56 disposed on the bulkhead 42. The hole in the eccentric sleeve 52 is formed with a loose fit to +1140 mm; is supported by the shaft 40 via a pair of needle bearings 58 disposed at both ends of the shaft 40. On the other hand, a hall bearing 60- is disposed on the +iii side of the eccentric sleeve 52, and this hall bearing 60 engages with the stopper 62 and is supported by the shaft 40. In addition, a pole bearing ring 64 is disposed on the rear side of the eccentric sleeve 54, and this pole bearing ring 64 is engaged with teeth rlT, which will be described later.As a result, the eccentric sleeve 52
It is rotatable in the direction of the +1+ line and cannot be moved in the +1+ line direction.

VI1 weight 6 weight 6-1 is applied to the shaft portion 55 of the eccentric sleeve 52.
This gear 66 meshes with teeth 11j 70 keyed to the output shaft of an electric motor 68. On the other hand, a gear 72 is keyed on the shaft 40, and this gear 70 meshes with teeth 176 keyed on the output shaft of the electric motor 74.

The compression hem 138 is rotatably supported on the eccentric portion 54 of the eccentric sleeve 52 via a pair of roller bearings 78 . As is clear from the above, the eccentric sleeve 52 is rotated independently by a '1F motor separate from the +h 40, so the rotation of the eccentric sleeve 52 causes the eccentricity to be interlocked, and due to the friction with the excavated object. For the piezoelectric to be rotated, 1.38 will be rotated in the rotational direction and speed of 1-1, regardless of the rotational direction and speed of the shaft 40.

A concrete pipe 78 is connected to the rear of the shield main body 32, and the shield main body 32 is propelled by a pusher shaft 80 arranged at the rear.

Two pipes 82.84 open toward the partition wall 420111j
Or is provided. - The force pipe 82 is a pipe that supplies mud water hat to the slip chamber 86, and the other pipe 84 is a pipe that supplies υ to the slip chamber 86.
This is a pipe that transports the excavated material to the rear. Furthermore, a cutter 88 is provided at the front end of the shaft 40.

The apparatus for carrying out the shield propulsion method shown in Fig. 2 is shown in Fig. 3.
8 is projected forward from the shield wooden cup 32.
A portion of the outer circumferential surface of the consolidation head 38 may be formed to have a size such that a seal 1 is applied to the external force in the radial direction of the main body 32.

The axial force acting on the consolidation head 38 passes through the rib 40 and is applied to the partition wall 4.
Roller bearing 4 arranged in casing 44 behind 2
Work at 6. Therefore, a load cell 90 is placed between the casing 44 and the front rolling bearing 46 to measure the axial force.
11. This detected value is displayed on the control panel 92.
A predetermined value of the axial force is set using the finger t1 of the two-point indicator 94 and the other finger t1 of the two-point indicator 94. A signal is sent from the control panel 92 to the electric motor 68 via a frequency converter 96 such as an in/heater.
Change the rotation speed of the electric motor 68. Also, from the control panel 92, press the frequency converter 98 with a light switch 80.
Sends faith to the power unit 100 and changes the propulsion speed of one shield body. This control can be operated singly or automatically.

The axial force acting on the load cell 90 is the reaction force of the soil generated on the excavated object, and this upper pressure reaction force is between the ground pressure and the passive upper pressure. Therefore, it is convenient to convert the determination and instructions of Compound 11 Instruction 1;( into JE force.

Before putting the shield propulsion device 3θ into the ground, first, the 1-pressure of the ground to be excavated is reduced to 1,1η, and then 1
; Find a range from "working" to "passive" and set a relatively high value to one finger of the return side type indicator 111. Then, the electric motor 68 and the electric motor 74 are driven, and the piezoelectric head 38 During this period, pressure oil is supplied from the power unit 100 to the main pushing shaft 80, and the pulse is applied to the shield body 32 via the concrete pipe 78, making it advance to 1. . Shield body 32
During propulsion, an axial force is applied to the load cell 90,
This is indicated by the other pointers of the multi-key indicator, 1192. This detected value is compared with the fixed value of 11, and the rotation speed of the electric motor 68 is changed through the 8-wave number converter 96, and the rotation speed of the electric motor (not shown) of the power unit 100 is changed through the frequency att+ converter 98. and perform the operations described above.

(Effect of civilization) According to the present invention, instead of rotating the excavated object within the shield body and guiding it to υl' jl, i l-,1, the excavated object is guided in a straight line by consolidation and earth pressure reaction force. Since the material is guided directly to the discharge port, the frictional force acting on the consolidation head is reduced.
Alternatively, since the consolidation vent is eccentrically interlocked in front of the shield body, the frictional force acting between the shield body, the bond, and the ground is reduced.

As a result, power can be significantly reduced.

In addition, by changing the rotational speed of the consolidation head or (and) the propulsion speed of the shield body, it is possible to cope with and synchronize with the fluctuations in the tonosho, so it is safe against 1-hour accidents such as ground collapse. Can be secured promptly.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional explanatory diagram showing the m-adic method according to the present invention, and FIG.
Figure 3 is a cross-sectional explanatory diagram showing another propulsion method according to the present invention.
This figure is a sectional view showing an apparatus for carrying out the propulsion method shown in FIG. 1. 10.24.32+Shield body, 12.36・Space, ], 4, 76, 38: Piezoelectric vent, 19: Face, 28・Ground, 40++l+, 52: Eccentric sleeve, 80: Main push shank, 90 "Load cell, 92 Multi-needle indicator, 96, 98: Frequency converter. Agent: Nobuyuki Matsui, Br.

Claims (4)

[Claims] (1) The pressure head is eccentrically moved and rotated in front of the partition wall provided across the shield body, and during this time, thrust is changed to the shield body to propel the shield body into the ground, and the shield body is propelled into the ground. Or detect the dispelling force acting on the consolidation from the excavated material, and when the detected value exceeds a predetermined value, reduce the propulsion speed of the seal I/main body or・Shield m-adic method to increase the speed of eccentric movement. (2) The shield propulsion method according to claim (1), wherein the consolidation vent is eccentrically moved within a space of the shield body provided in front of the partition wall. (3) The shield propulsion method according to claim (1), wherein the piezoelectric vent is eccentrically moved at a position in front of the shield main body. (4) The consolidation vent is eccentrically moved and rotated on the side of the partition wall provided across the shield body, and during this time, thrust is applied to the shield body to propel the shield body into the ground; The axial force acting on the consolidation head from the ground or its excavated material is detected, and when the detected value exceeds a predetermined value, the propulsion speed of the shield body is reduced and at the same time the eccentric interlocking speed of the consolidation head is increased. Hello, shield propulsion method.