JP2010190008A - Shield machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a shield machine capable of smoothly excavating ground at low cost by a simple facility without requiring the use of bentonite, a cement-based material, or the like and without generating industrial waste irrespective of the type of the ground. <P>SOLUTION: This shield excavator 10 includes a generally cylindrical shield 11, an excavation cutter head 13 for excavating the ground, an agitating blade 15 for agitating excavated soil which has a diameter smaller than the excavation cutter head 13 and is rotatingly driven in the direction reverse to the rotating direction of the excavation cutter head 13, an excavated soil rotating and feeding device 23 which rotates and moves the excavated soil from the lower portion to the upper portion along the inner peripheral surface of the shield 11 and falls the excavated soil rearward when the excavated soil reaches the upper portion, and a conveyor 16 for feeding the excavated soil rearward. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a shield excavator for ground excavation for creating a tunnel such as a subway.

2. Description of the Related Art Conventionally, shield tunneling machines such as a mud pressure type and a mud pressure type have been used when constructing a tunnel such as a subway.
In these shield machines, the excavated soil is plastic fluidized by adding mud and the like, and then discharged to the rear of the shield machine (see, for example, Patent Document 1).

Japanese Examined Patent Publication No. 5-12520

A mud pressurizing shield machine is a generic term for specific gravity adjusting materials such as bentonite and viscous materials such as carboxymethylcellulose (CMC) (hereinafter referred to as materials for plastic fluidization) in order to plastically fluidize excavated soil. Called plastic fluidizing material). The plastic fluidized excavated soil is dewatered by a dewatering means such as a filter press and then treated as industrial waste.
On the other hand, the mud pressure type shield machine uses a mud material to plastically fluidize the excavated soil. Since the plastic fluidized excavated soil has properties that are difficult to transport with a truck or the like, it is treated as industrial waste after adding a solidifying material such as cement or a polymer aggregate to facilitate transport.
As described above, there is a problem that industrial waste is generated in both the mud pressurizing type and the mud pressure type shield machines.
In addition, the mud pressurizing shield machine requires a dewatering means such as a filter press, and the mud pressure shield machine requires a tank for storing materials such as cement. However, there were problems such as an increase in construction site and an increase in construction costs due to these facilities.
Therefore, the present invention does not require the use of a plastic fluidizing material such as bentonite or a solidifying material such as cement regardless of the ground, and does not generate industrial waste. An object of the present invention is to provide a shield machine that can smoothly perform the excavation.

As a result of studying to solve the above-mentioned problems, the present inventor has arranged a specific agitating blade, a specific excavated soil rotating and feeding device, and a conveyor in this order behind the excavation carter head for excavating the ground. As a result, it is not necessary to use plastic fluidizing materials such as bentonite or solidifying materials such as cement, and any soil can be sent to the back of the shield machine smoothly without generating industrial waste. The present invention was completed by finding that it can be used as landfill material as ordinary soil.
That is, the present invention provides the following [1] to [3].
[1] (a) a substantially cylindrical shield, and (b) excavating the ground disposed in the vicinity of the front end of the shield, having a substantially disk shape, having substantially the same diameter as the shield, and driven to rotate. An excavation cutter head for carrying out, and (c) disposed at an appropriate distance behind the excavation cutter head, having a substantially disk shape, having a smaller diameter than the excavation cutter head, and being driven to rotate. An agitating blade for agitating the excavated soil, and (d) a rotating excavator rotating and feeding device disposed behind the agitating blade, wherein the excavated soil rotates from the lower part to the upper part along the inner peripheral surface of the shield. Excavated soil rotation and delivery device configured to move and fall backward when it reaches the upper part, and (e) a conveyor for delivering the excavated soil dropped by the excavated soil rotation and delivery device to the rear It is characterized by having Shield machine.
[2] The inner peripheral surface of the front end of the shield is formed as a frustoconical guide surface whose diameter decreases from the vicinity of the periphery of the excavation cutter head toward the periphery of the stirring blade. Shield machine.
[3] The excavated soil rotation and delivery device includes: (i) a substantially cylindrical horizontal wall having the same axis as the shield and having an outer diameter smaller than the inner diameter of the shield, and the vicinity of the upper end of the front end of the horizontal wall A partition wall fixed to the shield, and having a hole for excavating soil at each of the upper and lower ends of the horizontal wall; and (ii) An approximately donut-shaped rotationally driven excavation soil rotating portion disposed between an inner peripheral surface and the outer peripheral surface of the horizontal wall of the partition wall portion, and a plurality of openings that open toward the axis of the shield A shield excavator according to [1] or [2], further comprising: an excavated soil rotating unit having an excavated soil accommodating chamber.

According to the shield machine of the present invention, it is not necessary to use a plastic fluidizing material such as bentonite or a solidifying material such as cement in any ground, and it is possible to smoothly excavate soil without generating industrial waste. The excavated soil can be sent to the rear of the shield machine and then used as ordinary soil (ordinary soil containing no cementitious material) for landfill.
In addition, the entire construction facility including the shield machine can be simplified and reduced in size, and the construction cost can be reduced.

FIG. 1 is a cross-sectional view of a main part of an example of a shield machine according to the present invention. FIG. 2 is a cross-sectional view of the excavated soil rotation and delivery device of the shield machine cut along the line AA in FIG.

Hereinafter, an example of the shield machine of the present invention will be described with reference to the drawings.
In FIG. 1, the shield machine 10 includes a shield 11, an excavation cutter head 13 disposed near the front end of the shield 11, an agitation blade 15 disposed behind the excavation cutter head 13, The excavated soil rotation and delivery device 23 is provided behind, and the conveyor 16 is provided behind the excavated soil rotation and delivery device 23. In the present specification, the direction in which the shield machine advances is called “front”, and the opposite direction is called “rear”.
The shield 11 is for protecting the shield machine against earth pressure or the like from the inner peripheral surface of the tunnel that is formed by excavating the ground and is not primary-covered, and is formed in a substantially cylindrical shape. Yes. The shield 11 is a part of the main body of the shield machine 10 and moves forward without rotating. The shield 11 may be referred to as a shield body, a skin plate, or the like.
The excavation cutter head 13 is rotationally driven by a rotary shaft 12 having a substantially disk shape, substantially the same diameter as the shield 11, and having the same axis as the shield 11. The excavation cutter head 13 has a large number of excavation cutters 18 on its front surface, and the excavation cutter 18 can excavate the ground. The excavation cutter 18 may be referred to as a cutter bit or the like.
The excavation cutter head 13 can be formed in a flat plate shape. However, when the excavation cutter head 13 is formed in a substantially dome shape with the center portion bulging forward, the earth and sand (excavation soil) generated by excavating the ground is It becomes easy to enter the chamber 14 through the excavated soil intake 19 from the periphery, which is preferable.
Instead of the rotary shaft 12, driving means that abuts on the peripheral edge of the excavation cutter head 13 can also be used.

The stirring blade 15 is disposed behind the excavation cutter head 13 via a chamber 14 that is an internal space. The stirring blade 15 is substantially disk-shaped and has a smaller diameter than the excavation cutter head 13 and is driven to rotate about the same axis as the excavation cutter head 13.
In the example shown in FIG. 1, the stirring blade 15 is formed in a flat plate shape. However, similarly to the excavation cutter head 13, the stirring blade 15 may be formed in a substantially dome shape with a central portion expanded forward.
The agitating blade 15 has a large number of agitating cutters 21 on the front surface thereof, and the agitating cutter 21 agitates the excavated soil in the chamber 14 to achieve condensation and plastic fluidization. In general, the excavated soil after excavation by the excavating cutter head 13 swells to a volume about 1.3 times that before excavation because the voids between the soil particles increase. If the swelled excavated soil is left in an inflated state, it cannot resist the earth pressure on the excavation surface (face) of the ground, and the face may collapse, so excavation is performed in the chamber 14. The soil is condensed to increase the density, thereby resisting the earth pressure of the face and preventing the face from collapsing.
A plurality of stirring cutters (not shown) can also be provided on the rear surface of the stirring blade 15. In this case, the excavated soil in the space between the stirring blade 15 and the inclined wall 17d can be stirred to increase the degree of plastic fluidization.
The stirring blade 15 is preferably rotated in the direction opposite to the rotation of the excavation cutter head 13. By rotating in the reverse direction, the degree of condensation of the excavated soil in the chamber 14 can be increased, and the agitation action of the excavated soil in the chamber 14 can be enhanced to further increase the degree of plastic fluidization of the excavated soil. Can do.
The rotational speed of the agitating blade 15 may be determined as appropriate from the viewpoint of agglomeration of the excavated soil and plastic fluidization independently of the rotational speed of the excavating cutter head 13.

The diameter of the stirring blade 15 is determined according to the shape of the front end portion of the shield 11. Preferably, the inner peripheral surface of the front end portion of the shield 11 is formed as a frustoconical guide surface whose diameter decreases from the vicinity of the periphery of the excavation cutter head 13 toward the vicinity of the periphery of the stirring blade 15. In this case, the degree of agglomeration of the excavated soil in the chamber 14 can be further increased to enhance the action against the earth pressure of the face.
The stirring blade 15 is rotationally driven by a rotating shaft (not shown) having the same axis as that of the shield 11, for example.
The excavated soil rotation delivery device 23 is disposed behind the stirring blade 15. The excavated soil rotation delivery device 23 does not move the excavated soil in the front-rear direction of the shield 11 but rotates it from the lower part to the upper part along the inner peripheral surface of the shield 11 and drops it backward when it reaches the upper part. It is configured as follows. By constructing in this way, while reducing the size of the shield machine (especially avoiding an increase in the overall length), it is freed from the front part for combating the earth pressure of the face and the earth pressure of the face. A boundary with the rear portion for delivery on the conveyor 16 can be formed.
Specifically, the excavated soil rotation and delivery device 23 is driven to rotate in a substantially donut shape disposed between the partition wall 17 fixed to the shield 11 and the inner peripheral surface of the shield 11 and the partition wall 17. It is comprised from the excavated soil rotating part 22.

Among these, the partition wall portion 17 is fixed to the inner surface of the shield 11 so as to divide the inner space of the shield 11 into a front space and a rear space, and is separated from the inner peripheral surface 11 a of the shield 11. A substantially annular vertical wall 17a extending perpendicularly to the axial direction of the shield 11 and an end on the inner side of the guide surface 11b of the shield 11 by bending vertically at or near the inner end of the vertical wall 17a A cylindrical horizontal wall 17b reaching the vicinity and an inclined wall 17d reaching from the vicinity of the upper end of the front end of the horizontal wall 17b to the vicinity of the lower end of the rear end, and holes for excavating soil fall at the upper end and the lower end of the horizontal wall 17b. 17c and 17e.
The space on the front side and the space on the rear side of the inclined wall 17d are separated by the inclined wall 17d and the partition wall 22d (see FIG. 2) of the excavated soil rotating unit 22. Therefore, the excavated soil accommodated in the space between the inclined wall 17d and the stirring blade 15 falls through the excavated soil dropping hole 17e, and then rotates and moves from the lower portion to the upper portion in the shield 11 by the excavated soil rotating portion 22. Then, it falls from the upper part through the excavation soil dropping hole 17c.

The excavated soil rotating portion 22 includes a cylindrical horizontal wall 22a formed along the inner peripheral surface of the shield 11, and a vertical wall 22b that is bent vertically at the rear end of the horizontal wall 22a and extends to the vicinity of the horizontal wall 17b. And an inclined wall 22c that is bent at an obtuse angle at the front end of the horizontal wall 22a and extends to the vicinity of the horizontal wall 17b along the inner surface of the shield 11, and a horizontal wall 22a, a vertical wall 22b, and an inclined wall 22c. It is a substantially donut-shaped object composed of a plurality of partition walls 22d (see FIG. 2), which are walls extending perpendicularly to the respective portions 22a to 22c, for dividing the grooves to form excavated soil accommodation chambers. The excavated soil rotating unit 22 is driven to rotate about the same axis as the rotating shaft 12.
The plurality of partition walls 22d are for forming a plurality of excavated soil accommodation chambers that open in the direction of the axis of the shield 11 with the horizontal wall 22a as the bottom. The height of the partition wall 22d is the same as the height of the vertical wall 22b and the inclined wall 22c. The inner end of each part of the vertical wall 22b, the inclined wall 22c, and the partition wall 22d is positioned in the vicinity of the horizontal wall 17b so that it can rotate without contacting the horizontal wall 17b of the partition wall part 17. is doing.
Examples of the rotation driving device for rotating the excavated soil rotating unit 22 include a rotation driving track provided on the inner peripheral surface of the shield 11 and the outer peripheral surface of the horizontal wall portion 22a, or a vertical wall 17a. Only the horizontal wall 17b is fixed to the shield 11 without being provided, and the support attached to the rear surface of the vertical wall 22b is driven to rotate about the same axis as the axis of the shield 11. .
Although the number of excavation soil accommodation chambers is not specifically limited, Preferably it is 4-20, More preferably, it is 6-12. In the example shown in FIG. 2, the number of excavated soil accommodation chambers is eight.
A plurality of holes for blowing compressed air from the outside into the excavated soil accommodation chamber can be provided in the horizontal wall portion 22a which is the bottom of the excavated soil accommodation chamber. In this case, the excavated soil in the excavated soil accommodation chamber can be quickly dropped by configuring so that the compressed air is blown when the excavated soil accommodating chamber reaches the upper end in the shield 11.
The rotational speed of the excavated soil container 22 may be appropriately adjusted in consideration of the amount of excavated soil generated per unit time.
The conveyor 16 is for sending the excavated soil dropped through the excavated soil dropping hole 17c backward. Examples of the conveyor 16 include a screw conveyor.

The ground excavation work in the shield machine 10 shown in FIG. 1 is performed as follows.
First, the ground is excavated by the excavation cutter 18 of the excavation cutter head 13 to generate excavated soil. This excavated soil is taken into the chamber 14 at an excavated soil intake 19 which is an opening between the front end of the shield 11 and the peripheral edge of the excavated cutter head 13. The taken excavated soil is stirred in the chamber 14 and condensed (densified) and plastic fluidized (highly fluidized).
Thereafter, the excavated soil in the chamber 14 is taken into the space behind the stirring blade 15 in the intake space (intake port) 20 that is an opening between the stirring blade 15 and the shield 11. The taken excavated soil falls into the excavated soil accommodating chamber of the excavated soil rotating unit 22 through the excavated soil dropping hole 17e provided in the horizontal wall 17b of the partition wall portion 17.
Next, as shown in FIG. 2, the excavated soil 24 accommodated in the excavated soil accommodating chamber of the excavated soil rotating unit 22 is shielded by the excavated soil rotating unit 22 rotating in the direction indicated by the arrow in the figure. 11 is rotated from the lower part to the upper part, and when it reaches the upper part, it falls through the excavation soil dropping hole 17c (see FIG. 1) and slides down along the upper surface of the inclined wall 17d. It enters the intake port 16a which is a hole provided in a certain cylindrical portion, and is sent backward by the rotation of the screw of the conveyor 16.

In the internal space of the shield machine 10, a portion containing the agglomerated excavated soil (a portion of the agglomerated soil) that opposes the earth pressure on the excavation surface (face) of the ground, and released from the earth pressure and sent backward There is a portion (a portion of non-aggregated soil) containing excavated soil in which the interval between the soil particles is widened. Among these, the agglomerated soil part includes the space in the chamber 14, the space between the stirring blade 15 and the inclined wall 17 d, and the excavated soil accommodating chamber in the process of moving the excavated soil from the lower part to the upper part by the excavated earth rotating unit 22. It consists of a space. The portion of the non-aggregated soil includes a space in the excavated soil accommodation chamber that accommodates the excavated soil that reaches the upper portion and falls downward by the excavated soil rotating unit 22, a space in the conveyor 16, and the like. In the present invention, since the excavated soil rotation sending device 23 composed of the partition wall portion 17 and the excavated soil rotating unit 22 is provided, the excavated soil existing in the inner space of the shield machine 10 is divided into the agglomerated soil portion and the non-agglomerated soil portion. The excavated soil can be smoothly fed backward at a uniform supply speed while resisting the earth pressure of the face.

DESCRIPTION OF SYMBOLS 10 Shield machine 11 Shield 11a Inner peripheral surface 11b Frustum-shaped guide surface 12 Rotating shaft 13 Excavation cutter head 14 Chamber (internal space)
DESCRIPTION OF SYMBOLS 15 Stirring blade 16 Conveyor 16a Intake port 17 Partition part 17a Vertical wall 17b Horizontal wall 17c Excavation soil fall hole 17d Inclined wall 17e Excavation soil fall hole 18 Excavation cutter 19 Excavation soil intake 20 Intake space (intake) )
21 Stirring Cutter 22 Excavating Soil Rotating Unit 23 Excavating Soil Rotating Delivery Device 24 Excavating Soil

Claims (3)

A substantially cylindrical shield;
An excavation cutter head for excavating the ground, which is disposed in the vicinity of the front end of the shield, has a substantially disc shape, has substantially the same diameter as the shield, and is driven to rotate;
An agitating blade for agitating the excavated soil, which is disposed behind the excavating cutter head at an appropriate distance, is substantially disk-shaped and has a smaller diameter than the excavating cutter head, and is driven to rotate;
The excavated soil rotating and feeding device disposed behind the agitating blade, wherein the excavated soil is rotated from the lower part to the upper part along the inner peripheral surface of the shield and dropped when reaching the upper part. Excavating soil rotation and delivery device configured to move to,
A conveyor for delivering the excavated soil dropped by the excavated soil rotation delivery device to the rear;
A shield machine characterized by comprising   2. The shield machine according to claim 1, wherein an inner peripheral surface of the front end of the shield is formed as a frustoconical guide surface whose diameter decreases from the vicinity of the periphery of the excavation cutter head toward the periphery of the stirring blade. . The excavated soil rotation delivery device is:
The horizontal wall having a substantially cylindrical shape having the same axis as the shield and having an outer diameter smaller than the inner diameter of the shield, and an inclined wall spanning from the vicinity of the upper end of the front end of the horizontal wall to the vicinity of the lower end of the rear end, And the partition part fixed to the shield which has a hole for excavation soil fall in each of the upper end and the lower end of the horizontal wall,
An excavation soil rotating part, which is disposed between the inner peripheral surface of the shield and the outer peripheral surface of the horizontal wall of the partition wall, and is driven to rotate substantially in a donut shape, and is open toward the axis of the shield. Excavated soil rotating part having a plurality of excavated soil storage chambers,
The shield machine according to claim 1 or 2, further comprising:

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