JP2002070481A - Open shield machine and open shield method making use thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an open shield machine capable of surely preventing the collapse of a bedrock side section of the upper part of a baserock when a downward baserock layer of the bedrock is excavated after the bedrock of the upper part of the baserock layer when there is a hard baserock layer in the bottom in an excavated section and in the case the bedrock of the upper part of the baserock layer and the baserock layer are divided into two stages to separately excavate them and also having a simple structure for accomplishing the purpose. SOLUTION: Pipe jacks 2 are arranged at the insides of right and left side wall boards 1a as a side earth retaining board, and in the open shield machine opening the front, the rear and the upper surface, a preceding earth retaining board 12 is constituted of a partition wall 12a set between the right and left side wall boards 1a so as to close ahead of the front section 1d and the right and left side wall boards 1a, the preceding earth retaining board 12 is mounted on the front section 1d in a slidable manner, the bedrock of the upper part of the baserock in front of the preceding earth retaining board 12 is excavated to drive the preceding earth retaining board 12 forward, an excavation working space is formed in front of a cutting face section of the shield machine between the cutting face section and the preceding earth retaining board 12, and after the baserock layer in the bottom of the cutting face is excavated in the space to remove earth, the open shield machine is driven forward.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an open shield machine for constructing underground structures such as water and sewage systems and underpasses in an urban area, and an open shield method using the open shield machine.

[0002]

2. Description of the Related Art The open shield method is a highly rational method utilizing the advantages of the open-cut method (open cut method) and the shield method. The outline of the open shield machine 1 used in this open shield method is shown in FIG. Left and right side walls 1a and bottom plate 1b connected to these side walls 1a
The front, rear and upper surfaces of the side wall 1a and the bottom plate 1b are formed as cutting edges, and the propulsion jack 2 is vertically moved toward the center or near the rear end of the side wall 1a. Arrange them side by side. In the figure, reference numeral 3 denotes a partition.

[0003] The open shield method using the open shield machine 1 is not shown in the drawings, but the open shield machine 1 is installed in a starting pit, and the propulsion jack 2 of the open shield machine 1 is extended. The open shield machine 1 is advanced by applying a reaction force to the reaction wall in the starting mine, and the first concrete box 4 forming the underground structure is suspended from above, and the tail portion 1c of the open shield machine 1 is lowered. Set it behind the propelled jack 2 that was shortened.
A strut is provided between the propulsion jack 2 and the reaction force wall to adjust the distance as appropriate.

The starting pit is constituted by a retaining wall, and the retaining wall is partially mirror-cut in order to start the open shield machine 1. However, if necessary, a ground improvement is performed on a front portion of the starting pit by injecting a chemical solution or the like. May be given.

An excavator 9 such as a shovel excavates earth and sand from the front or upper surface of the open shield machine 1 and discharges the earth. Simultaneously with or after this earth removal step, the propulsion jack 2 is extended to move the open shield machine 1 forward. In the case of this advancing process, a pressing angle 8 composed of a frame using a box steel material or a mold steel is disposed in front of the concrete box 4.

[0006] The first concrete box 4
Before the second concrete box 4 is suspended in the tail part 1c of the open shield machine 1. Hereinafter, the same earth removal process, advance process, and setting process of the concrete box 4 are appropriately repeated, and the concrete box 4 is sequentially left under the ground as the open shield machine 1 advances, and the concrete box 4 is further removed. Put backfill soil 5 on the upper surface of 4.

When suspending the concrete box 4 in the tail portion 1c of the open shield machine 1, a height adjusting member 7 such as a concrete block is disposed under the concrete box 4, and the tail is removed. The grout material 6 is filled into the left and right and lower spaces of the concrete box 4 in the portion 1c.

In this way, when the open shield machine 1 reaches the destination pit, it is removed and the construction is completed.

In such an open shield method, the concrete box 4 is connected to the open shield machine 1 as described above.
Left in the ground in tandem with the advance of
Is suspended in the tail of the open shield machine 1,
As the open shield machine 1 advances, it leaves the tail portion 1c and remains in the ground.

The concrete box 4 is made of reinforced concrete and comprises a left side plate 4a, a right side plate 4b, an upper floor plate 4c, and a lower floor plate 4d as shown in FIG. I have.

[0011]

Problems to be Solved by the Invention Open Shield Machine 1
When excavating, the left and right side plates 1a function as earth retaining plates, and excavate and excavate earth and sand from the front or upper surface of the open shield machine 1 with an excavator 9 such as a shovel. When a hard rock layer exists at the bottom, it is difficult to excavate the hard rock layer with an excavator 9 such as a shovel.

[0012] Therefore, the ground above the bedrock layer is separated from the bedrock layer, and the bedrock above the soft bedrock made of earth and sand is excavated and excavated by an excavator such as a backhoe. Excavation of the ground has secured a space for excavation of the bedrock layer, and excavation and excavation are performed using a separate excavator such as a breaker.

When excavating a hard rock layer at the bottom of the excavated cross section, it is difficult to prevent collapse of the top of the rock mass on the ground side only by the left and right side walls 1a.

An object of the present invention is to solve the problem of the prior art, wherein a hard rock layer is present at the bottom of an excavated cross section, and the ground at the upper part of the rock layer and the rock layer are separately excavated in two stages. An open shield that can reliably prevent the collapse of the upper part of the rock layer when excavating the lower rock layer after excavating the rock layer above the rock layer, and a simple structure is sufficient for that. And an open shield method using the open shield machine.

[0015]

In order to achieve the above object, the present invention firstly provides an open shield machine in which propulsion jacks are arranged inside left and right side wall plates, and the front, rear and upper surfaces are opened. In the shield machine, a leading earth retaining plate is formed by the partition wall disposed between the left and right side wall plates and the left and right side wall plates so as to close the front of the front part, and the preceding earth retaining plate is slidably attached to the front part. The gist is that

Secondly, the preceding earth retaining plate is to be disposed only in the upper part of the front part.

Thirdly, the gist of the invention is to provide a towing jack for correcting the upper direction of the preceding retaining plate between the preceding retaining plate and the front portion.

Fourth, as an open shield method, a propulsion jack is arranged inside the left and right side wall plates, and excavates and removes earth and sand in front of the front or upper surface opening of the open shield machine having the front, rear and upper surfaces opened. The process and the process of extending the propulsion jack to advance the shield machine with the reaction force of the concrete box, and suspending the new concrete box from above behind the propelled jack shrunk in the tail part of the shield machine In the open shield method of connecting and embedding concrete boxes sequentially in a row by repeating the setting step as appropriate, in the open shield construction method, the partition wall and the left and right side wall plates disposed between the left and right side wall plates so as to block the front of the front part. A preceding earth retaining plate is formed, the preceding earth retaining plate is slidably attached to the front portion, and the ground above the bedrock in front of the preceding earth retaining plate is excavated. Advancing the earth retaining plates, the excavation work space is formed between the leading soil retaining plate in front of the working face of the shield machine, after a rock layer of tunnel face bottom excavated earth removal in the space,
The gist is to advance the open shield machine.

Fifth, in the propulsion process of the open shield machine, an appropriate amount of excavated soil is injected into a rock excavation portion at the bottom of the face,
The gist of the present invention is to apply a constant earth pressure to the bottom and top of the face during propulsion of the open shield machine.

Sixth, the advancement of the preceding retaining plate is performed by a propulsion jack provided on the preceding retaining plate side, a slide jack provided between the preceding retaining plate and the front portion of the open shield machine, and the open shield machine. The gist of the invention is to appropriately use a propulsion jack for propelling the shield machine provided.

According to the first and fourth aspects of the present invention, the ground above the bedrock in front of the preceding retaining plate is excavated to advance the preceding retaining plate, and the preceding soil is disposed in front of the face of the shield machine. If the excavation work space is formed between the retaining plate and the rock layer at the bottom of the face is excavated and discharged in the space, the space is surrounded by the preceding retaining plate on both sides and the front, so that the upper part of the rock is The collapse of the ground can be prevented and safety can be ensured.

According to the second aspect of the present invention, in addition to the above operation, the preceding retaining plate is disposed only on the upper portion of the front portion, so that the ground at the top of the bedrock in front of the preceding retaining plate is provided. After excavation, when the preceding retaining plate is advanced,
The preceding retaining plate does not hit the bedrock layer at the bottom of the face,
Dig over it smoothly.

According to the third aspect of the present invention, in addition to the above operation, by providing a tow jack for correcting the upper direction of the preceding earth retaining plate between the preceding earth retaining plate and the front portion, The preceding retaining plate can be correctly set at a predetermined position by eliminating the influence of earth pressure and the like.

According to the present invention described in claim 5, according to claim 4,
In addition to the operation of the present invention described, in the propulsion process of the open shield machine, since an appropriate amount of excavated soil is injected into the rock excavation portion at the bottom of the face, a constant earth pressure is applied between the bottom face and the upper portion during the propulsion of the open shield machine. Thus, the open shield machine can be smoothly advanced in a predetermined direction.

According to the sixth aspect of the present invention, in addition to the above operation, the advancement of the preceding retaining plate is basically performed by a propulsion jack provided on the preceding retaining plate side, the preceding retaining plate and the open shield. Use the slide jack provided between the front of the machine and the jack.If these jacks do not have enough propulsion, use the propulsion jack for the propulsion of the shield machine provided in the open shield machine. By doing so, a predetermined propulsive force can be secured.

[0026]

Embodiments of the present invention will be described below in detail with reference to the drawings. 1 is a plan view of a main part showing an embodiment of the open shield machine of the present invention, FIG. 2 is a side view of the same, FIG. 3 is a front view of the same, FIG. 4 is a sectional view taken along line AA of FIG. As described above with reference to FIG. 9, the overall configuration of the shield machine 1 is such that the propulsion jacks 2 are disposed inside the left and right side wall plates 1a and the front, rear and upper surfaces are opened, so that detailed description is omitted here. I do.

In the open shield machine 1 of the present invention, the left and right side wall plates 1a provided on the left and right side portions in front of the front portion 1d also function as side earth retaining plates. Is slidably provided so as to protrude forward of the front portion 1d. In this case, as shown in FIG. 2, the left and right side wall plates 1a are formed to be shorter than the length of the front portion 1d in the height direction, and are disposed only in a portion above the front portion 1d.

Further, according to the present invention, a partition wall 12a is disposed substantially at the center of the left and right side wall plates 1a in the longitudinal direction, and a partition wall 12a is arranged between the left and right side wall plates 1a in a direction orthogonal to the left and right side wall plates 1a. The preceding earth retaining plate 12 is constituted by 1a and the partition wall 12a.

In the figure, reference numeral 11 denotes a slide jack disposed on the front portion 1d, and a propulsion jack 13 for propelling the preceding earth retaining plate 12 is connected to the slide jack 11 by, for example, two upper and lower propulsion jacks on the side of the partition wall 12a. Were arranged one by one.

In the figure, reference numeral 14 denotes a towing jack for correcting the direction, which is disposed on the upper side of the preceding retaining plate 12, and the towing jack 14 is connected to the front portion 1d.

Next, an open shield method using such an open shield machine 1 will be described with reference to FIGS. The open shield method is as shown in FIG. 14 as an outline of the entire method, and the detailed description is omitted. However, the excavation in the open shield machine 1 and the setting process of the concrete box 4 are repeated, and the concrete box 4 As the open shield machine 1 advances, the soil is left in the ground in a row, and the backfill soil 5 is put on the upper surface of the concrete box 4.

When a hard rock layer 15 exists at the bottom of the excavated cross section of the open shield machine 1, first, as shown in FIGS. 5 and 6, a preceding earth retaining plate 12 is provided in front of the front portion 1d of the open shield machine 1. Is placed, and the loosened soil at the top of the bedrock layer 15 is retained.

Next, as shown in FIG.
11. The propulsion jack 13 on the side of the preceding retaining plate 12 is contracted, and the ground retaining plate 12 is moved toward the front portion 1d, and the ground 18 above the bedrock layer 15 in front of the preceding retaining plate 12. Is excavated by an excavator 16 such as a backhoe.

After excavating the ground in front of the preceding retaining plate 12, FIG.
As shown in the figure, the slide jack 11 disposed on the front portion 1d, the propulsion jack 13 on the preceding retaining plate 12 side is extended to propel the preceding retaining plate 12, and the preceding retaining plate 12 and the front portion 1d are connected to each other. In the meantime, an excavation work space 19 for the bedrock layer 15 is secured. In this case, since the preceding retaining plate 12 exists only above the front portion 1d in the height direction, the preceding retaining plate 12 moves on the bedrock layer 15. 22 in the figure is slide jack 11
This is a piece to be interposed between the slide jack 11 and the propulsion jack 13 so that the propulsion jack 13 is appropriately joined to the head of the slide jack 11.

If necessary, the open shield machine 1
Is used at the same time to obtain the driving force of the preceding retaining plate 12. Further, the direction of the preceding earth retaining plate 12 is appropriately corrected using the towing jack 14.

Next, as shown in FIG. 9, an excavator 17 such as a breaker is used to break the rock bed 15 at the bottom of the excavation section in the excavation work space 19. Excavation may be performed manually for details. The rock excavated in the face is discharged by an excavator 16 such as a backhoe (see FIG. 10). The work of breaking the bedrock layer 15 at the bottom of the excavation section is surrounded by the preceding earth retaining plate 12 at the front and the left and right side wall plates 1a functioning as the earth retaining plates on the sides. Not
It can be done in a safe space.

After the excavation of the bedrock layer 15 at the bottom of the excavation section,
The open shield machine 1 is propelled by the propulsion jack 2 as shown in FIG. In addition, this open shield machine 1
At the time of propulsion, earth pressure is applied to the open shield machine 1 at the portion facing the preceding retaining plate 12 from the ground in front through the preceding retaining plate 12, but the portion where the bedrock layer 15 below it is excavated is Due to the space, no pressure is applied to the open shield machine 1. In order to apply a constant earth pressure when the open shield machine 1 is propelled, as shown in FIG.
An appropriate amount of excavated soil 20 from the ground 18 above the bedrock is put into the 15 excavated portions.

Then, as shown in FIG. 13, the slide jack 11 and the propulsion jack 13 on the side of the preceding retaining plate 12 are returned in this state, and the open shield machine 1 is propelled.

When the rock bed 15 at the bottom of the excavation section is broken using an excavator 17 such as a breaker,
In order to excavate the front part 1d of the open shield machine 1 below the open shield machine 1, a side clearance securing material 21 such as a steel rod is attached to the front part 1d at a rear position of the side wall plate 1a so that it can enter below the open shield machine 1. It can be provided in the middle. Although the side clearance securing member 21 is provided only on one side wall plate 1a in the example shown in FIG. 1, it may be provided on both sides.

[0040]

As described above, according to the open shield machine of the present invention and the open shield method using this open shield machine, the hard rock layer exists at the bottom of the excavated cross section, When excavating the rock mass above the bedrock layer and excavating the bedrock layer below it, the preceding earth retaining plate was provided in front of the open shield machine. The earth retaining plate can surely prevent the collapse of the ground side on the upper part of the bedrock, and a simple structure is sufficient for that purpose.

[Brief description of the drawings]

FIG. 1 is a plan view showing a main part of an embodiment of an open shield machine of the present invention.

FIG. 2 is a side view showing a main part of the embodiment of the open shield machine of the present invention.

FIG. 3 is a front view showing a main part of the embodiment of the open shield machine of the present invention.

FIG. 4 is a sectional view taken along line AA of FIG. 1 showing a main part of the embodiment of the open shield machine of the present invention.

FIG. 5 is a plan view showing a first step of the open shield method according to the present invention.

FIG. 6 is a front view showing a first step of the open shield method according to the present invention.

FIG. 7 is a vertical sectional side view showing a second step of the open shield method according to the present invention.

FIG. 8 is a vertical sectional side view showing a third step of the open shield method according to the present invention.

FIG. 9 is a vertical sectional side view showing a fourth step of the open shield method according to the present invention.

FIG. 10 is a vertical sectional side view showing a fifth step of the open shield method according to the present invention.

FIG. 11 is a vertical sectional side view showing a sixth step of the open shield method of the present invention.

FIG. 12 is a vertical sectional side view showing a sixth step of another example of the open shield method of the present invention.

FIG. 13 is a vertical sectional side view showing a seventh step of another example of the open shield method of the present invention.

FIG. 14 is a vertical sectional side view showing an outline of the open shield method.

FIG. 15 is a perspective view of a concrete box.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Open shield machine 1a ... Side wall plate 1b ... Bottom plate 1c ... Tail part 2 ... Propulsion jack 1d ... Front part 3 ... Partition wall 4 ... Concrete box 4a ... Left side plate 4b ... Right side plate 4c ... Upper floor plate 4d ... Lower floor plate 5 ... Backfill soil 6 ... Grout material 7 ... Height adjustment material 8 ... Push angle 9 ... Excavator 10 ... Opening 11 ... Slide jack 12 ... Preceding earth retaining plate 12a ... Partition 13 ... Propulsion jack 14 ... Towing jack 15 ... Roof bed 16 ... Excavator 17 ... Excavator 18 ... Ground 19 ... Excavation work space 20 ... Excavated soil 21 ... Side clearance securing material 22 ... Top

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hiroaki Takekawa 2-30-30 Hiyoshicho, Kokubunji-shi, Tokyo Uemura Giken Kogyo Co., Ltd. (72) Inventor Takayoshi Fuse 1-25-1, Nishishinjuku, Shinjuku-ku, Tokyo No. Taisei Corporation F term (reference) 2D054 AC16

Claims (6)

[Claims] 1. An open shield machine in which a propulsion jack is disposed inside left and right side wall plates and whose front, rear and upper surfaces are open, a partition wall disposed between the left and right side wall plates so as to close the front of a front portion. An open shield machine wherein a preceding earth retaining plate is constituted by the left and right side wall plates, and the preceding earth retaining plate is slidably attached to a front portion. 2. The open shield machine according to claim 1, wherein the preceding earth retaining plate is provided only in an upper portion of the front portion. 3. The open shield machine according to claim 1, wherein a traction jack for correcting the upper direction of the preceding retaining plate is disposed between the preceding retaining plate and the front portion. 4. A step of disposing a propulsion jack inside the left and right side wall plates, excavating and discharging earth and sand in front of the front or top opening of the open shield machine having the front, rear and top surfaces opened, and extending the propulsion jack. The concrete box as a reaction force to move the shield machine forward, and the step of hanging a new concrete box from above and setting it behind the propelled jack shrunk in the tail part of the shield machine as appropriate In the open shield method in which concrete boxes are connected in series and buried sequentially, the partition wall disposed between the left and right side wall plates and the left and right side wall plates constitute a preceding earth retaining plate so as to close the front of the front part. The preceding retaining plate is slidably attached to the front portion, the ground above the bedrock in front of the preceding retaining plate is excavated, the preceding retaining plate is advanced, and the shield machine is turned off. An open shield method characterized by forming an excavation work space in front of the wing portion with the preceding earth retaining plate, excavating and excavating the rock layer at the bottom of the face in the space, and then moving the open shield machine forward. . 5. In the propulsion process of the open shield machine, an appropriate amount of excavated soil is introduced into a rock excavation portion at the bottom of the face so that a constant earth pressure is applied to the bottom and upper portions of the face when the open shield machine is propelled. Open shield method described. 6. The advancement of the preceding retaining plate is carried out by a propulsion jack provided on the preceding retaining plate side, a slide jack provided between the preceding retaining plate and the front portion of the open shield machine, and an open shield machine. The open shield method according to claim 4, wherein the propulsion jack for propelling the shield machine is used as appropriate.