JPH0511200B2 - - Google Patents

Description

[Detailed Description of the Invention] (a) Industrial Application Field The present invention relates to a method for placing a lining, which is used when forming the lining of a tunnel excavated by a shield excavator with cast-in-place concrete. Regarding.

(b) Conventional technology Normally, when constructing the lining of a tunnel excavated by a shield excavator using cast-in-place concrete, a predetermined distance from the face side end face of the lining formed by the previous pouring is used. An end stop ring is installed at a separate position, and a concrete placement space is formed between the end stop ring and the end face on the face side. In this state, concrete is poured into the concrete placement space to construct a lining. Conventionally, in order to improve the strength of poured concrete, reinforcing members such as reinforcing bars and iron plates have been installed in a concrete pouring space in a fixed manner together with end rings.

(c) Problems to be Solved by the Invention However, with this, the stopper ring fixed to the reinforcing member gets in the way, making it difficult to fill the tail void created by the shield excavator with concrete. However, there was an inconvenience in that it was not possible to place and fill concrete precisely.

Further, Japanese Patent Laid-Open No. 109496/1983 discloses a technique in which a stop ring is provided movably in the direction of excavation, and by pressing the stop ring toward the rear of the outer shell, concrete is compacted. In this method, when an attempt is made to provide a reinforcing member within the rising lining so as to penetrate through the lining in the tunnel excavation direction in order to improve the strength of the constructed lining, the end stop ring and the reinforcing member moving in the tunnel excavation direction are This interference makes it difficult to move the end stop ring in the excavation direction, resulting in the inconvenience that concrete compaction and tail bolt filling cannot be performed sufficiently.

However, in order to improve the strength of the constructed lining, it is essential to install reinforcing members not only in the circumferential direction of the lining, but also through it in the tunnel excavation direction, and fill and reinforce tail voids with end rings. It has been desired to develop a lining installation method that allows members to be installed through the tunnel in the tunnel excavation direction.

In order to solve the above-mentioned problems, the present invention not only allows the reinforcing member to be installed penetratingly in the direction of tunnel excavation, but also efficiently fills the tail void that occurs after the excavator excavates with concrete, thereby achieving high reliability. It is an object of the present invention to provide a method for pouring a lining, which allows the lining to be formed by pouring.

(d) Means for solving the problem That is, the present invention has an outer shell 2 formed in a cylindrical shape, and moves a gauge ring 7 formed in an annular shape inside the outer shell in the direction of tunnel excavation. In a method for placing a lining using a shield excavator 1 provided in a freely drivable manner, reinforcing reinforcing bars 21 are installed between the face-side end surface of the already constructed lining 19 and the gauge ring.
a in the tunnel excavation direction, one end of which is connected to the end of the reinforcing reinforcing bar 21a that was installed last time, and the other end is connected to the reinforcing bar support means 7a provided in the gauge link to extend the tunnel. Installed so as to be movable relative to the gauge ring in the excavation direction, and an end stop ring 9 on the reinforcing reinforcing bar,
As the gauge ring moves in the tunnel excavation direction, it is provided so as to be movable in the excavation direction with respect to the reinforcing reinforcing bars, and concrete is placed between the end stop ring and the face side end surface of the already constructed lining. A construction space 22 is formed, and in that state, concrete 20 is poured into the concrete placement space, and when the concrete is poured and filled, the gauge ring is moved a predetermined distance to the rear of the outer shell. , the end stop ring is moved a predetermined distance behind the outer shell with the reinforcing steel supported within the reinforcing steel support means of the gauge ring, and by the movement of the end stop ring; The concrete placed in the concrete placement space is pressurized to fill the tail void 26 created by the movement of the outer shell with the concrete.

Note that the numbers in parentheses are for convenience and indicate corresponding elements in the drawings, and therefore, this description is not limited to the descriptions in the drawings. The same applies to the column "(e) Effect" below.

(e) Effect With the above-described configuration, the present invention provides reinforcement steel bars 21
With the end of a supported within the gauge ring 7 so as to be relatively movable, the end stop ring 9 is attached to the reinforcing reinforcing bar 2.
By moving relative to 1a, the concrete 20 in the concrete placement space 22 is pressurized, and the concrete 20 acts to fill the tail void 26.

(f) Embodiments Hereinafter, embodiments of the present invention will be described based on the drawings.

FIG. 1 is a front sectional view showing an example of a tunnel excavation site to which the lining casting method according to the present invention is applied; FIGS. 2 to 7 are process diagrams showing an example of the lining casting method according to the present invention; FIG. 8 is a perspective view showing the engagement relationship between the end stop ring and reinforcing reinforcing bars.

As shown in FIG. 1, the shield excavator 1 has a cylindrical outer shell 2, and a cutter head 3 is provided on the front surface of the outer shell 2, that is, on the left side in FIG. There is. Also, inside the outer shell 2 in the figure,
A plurality of shield jacks 6 are arranged in an annular shape along the outer shell 2, and a ram 6a is supported on the shield jacks 6 so as to be able to protrude and retreat in the directions of arrows A and B. A gauge ring 7 formed in an annular shape is attached to the tip of the ram 6a, and as shown in FIG.
A guide groove 7a is formed annularly around the entire circumference of the gauge ring 7. Further, an annular end stop ring 9 is in contact with the right side surface of the gauge ring 7 in FIG. 1, and an annular dowel 10 (see FIG. ) is installed. Furthermore, a plurality of guide holes 11 (see FIG. 8) are drilled through the end stop ring 9 in the directions of arrows A and B, opening into the guide groove 7a of the gauge ring 7. As shown in Fig. 1, between the end retaining rings 9, 9,
Concrete 20 is cast in a cylindrical shape. In addition, a plurality of reinforcing reinforcing bars 21a and 21b as reinforcing members are assembled and installed in the concrete 20, and the left end of each reinforcing reinforcing bar 21a in FIG. The guide groove 7a of the gauge ring 7 is fitted into the guide groove 7a.

Further, on the right side of the gauge ring 7 in FIG. 1, a casting form 12a assembled in an annular shape is installed so as to be movable in the directions of arrows A and B. The pouring form 12a is movable in the A and B directions, and has a
A reaction force receiving formwork 12b provided in a manner that can be fixed and unfixed at any position in the direction is in contact with the reaction force receiving form 12b,
On the right side of the reaction force receiving formwork 12b in the figure, a plurality of formwork propelling jacks 13 for moving these formworks 12a, 12b in the A direction are arranged in a circular ring.

Since the shield excavator 1 has the above configuration, when excavating the tunnel 15, the ram 6a of the shield jack 6 is made to protrude in the direction B in FIG. The outer shell 2 is pressed in the direction A by the reaction force received by the reaction force receiving form 12b. When the outer shell 2 is pressed in the direction A, the cutter head 3 is pushed in the direction of the face 16 with a predetermined excavation pressure, and the earth and sand in the face part is excavated. When the earth and sand in the part of the face 16 is excavated, the outer shell 2 is moved by the pressing force of the shield jack 6 by the amount of excavation of the face 16.
Propelling in this direction, a tunnel 15 is formed behind the shield excavator 1, ie to the right in FIG.

As the tunnel 15 is formed in this way, it is necessary to construct the lining 19 in order to prevent the excavated tunnel ground 17 from collapsing, and the construction of the lining 19 is performed in the following procedure. That is, when the shield excavator 1 has dug in the A direction by a length L1 corresponding to one ring of the pouring formwork 12a, the ram 6 of the shield jack 6
As shown in FIG. 2, a is in a state of protruding in the B direction. In this state, as shown in FIG. 3, the ram 6a is moved back in the A direction by a distance L1.
Then, the stopper ring 9A and the pouring formwork 12a installed during the previous pouring of concrete 20
The gauge ring 7 moves away from the center and moves in the A direction, and a space of a distance L1 is formed between the end stop ring 9A and the casting form 12a and the gauge ring 7. Therefore, first, as shown in Fig. 4, in the space part,
The end stop ring 9B and reinforcing reinforcing bars 21a and 21b as reinforcing members are assembled and installed in such a manner that the end stop ring 9B is brought into contact with the gauge ring 7. To do this, first insert a plurality of reinforcing reinforcing bars 21a into a plurality of guide holes 11 formed in the end stop ring 9B, as shown in FIG. The reinforcing reinforcing bars 21a are installed in the directions of arrows A and B, which are the tunnel excavation directions, by joining with the left end portions of each reinforcing reinforcing bars 21a installed during concrete pouring. Next, in this state, reinforcing reinforcing bars 21b are installed in a ring shape to surround these newly installed reinforcing reinforcing bars 21a. In this way, the reinforcing reinforcing bars 21a, 21b and the end stop ring 9
After B has been assembled and installed, the formwork propulsion jack 13 installed on the right side of FIG. 1 is driven to move the casting form 12a in the direction of arrow A together with the reaction force receiving form 12b. Then, the pouring formwork 12a
As shown in FIG. 5, it is fitted into the inner circumferential surface 7b of the gauge ring 7, and concrete is poured between the casting form 12a, the gauge ring 7 (end stop ring 9B) and end stop ring 9A. A space 22 is formed. Note that the left end portion of each reinforcing reinforcing bar 21a in FIG. Further, the end stop ring 9B is also engaged with the reinforcing reinforcing bar 21a so as to be movable relative to the reinforcing reinforcing bars 21a in the directions of arrows A and B.

In this way, when the concrete casting space 22 is formed, the concrete supply pipe 23 is connected to the concrete casting form 12a, and the concrete supply pipe 23 is
Concrete 20 is injected and placed into concrete placement space 22 by.

In this way, when the concrete 20 is substantially poured into the concrete placement space 22, the cutter head 3 is driven, and the ram 6a of the shield jack 6 is made to project in the direction of FIG. 5B.
Then, the gauge ring 7 attached to the ram 6a
moves by a distance L2 in the B direction together with the end stop ring 9, and the right side surface 7c of the gauge ring 7 comes into contact with the left side surface in the figure of the pouring formwork 12a. Furthermore, when the ram 6a moves in the direction B in this state, the outer shell 2 receives a reaction force from the casting form 12a and the reaction force receiving form 12b via the gauge ring 7, as shown in FIG. shape, move in direction A. Note that while the gauge ring 7 moves in the direction B by a distance L2, the end stop ring 9B is guided by the fixed reinforcing reinforcing bar 21a via the guide hole 11 by the gauge ring 7, and is guided by the arrow in FIG. The concrete 20 moves in the B direction in the concrete placement space 22 relative to the reinforcing steel bars 21a, and is placed in the space 22.
compress. Therefore, after the outer shell 2 passes, a tail void 26 is generated as shown in FIG.
The pressurized concrete 20 in the concrete casting space 22 immediately flows in and closes it, so that the lining 19 is cast in a good condition in close contact with the tunnel ground 17. Note that since the concrete 20 in the concrete placement space 22 at this point has not yet hardened, the tail void 26 is filled with the concrete 20 smoothly. Note that when the end stop ring 9B is moved and driven in the direction of arrow B by the gauge ring 7, the tip of the fixed reinforcing reinforcing bar 21a moves in the direction of arrow B.
Since the gauge ring 7 moving in the direction moves relatively in the direction of the arrow A in the guide groove 7a, the movement of the end stop ring 9 due to the movement of the gauge ring 7 in the direction B is such that the end stop ring 9 Coupled with the fact that it is movable with respect to 21a, the reinforcing reinforcing bars 21a can be smoothly connected to the gauge ring 7 and end stop ring 9 without interfering with each other.

Note that when the outer shell 2 moves in the direction A, the cutter head 3 provided on the left side of the outer shell 2 in FIG.
6 with a predetermined contact pressure, the face 16 is in contact with the cutter 3
excavated by. At the same time, the outer shell 2 is propelled in the direction A, and a tunnel 15 is formed behind the shield excavator 1, that is, to the right in FIG.

Further, in this embodiment, the inner circumferential surface 19a of the lining 19 in FIG.
We have described the case where the concrete is poured along the B direction, but when constructing a curve, etc., the inner circumferential surface 19
When pouring and forming the lining 19 where a does not align with the A and B directions, as shown in FIG. 7, the ram 6
When the outer shell 2 is moved in the A direction by protruding in the B direction, the reaction force can be stably taken from the reaction force receiving form 12b via the pouring form 12a. On the right side 7c of the gauge ring 7,
It is preferable to install a correction block 25 that can come into contact with the entire left side surface of the casting form 12a, which is installed at an angle with respect to directions A and B, to stably absorb the reaction force.

In addition, the shield excavator 1 itself has an erecta 27
When excavating in a place with poor ground, the gauge ring 7 can be removed and the excavator can be used as a general shield excavator by assembling segments.

(g) Effects of the Invention As explained above, the present invention has an outer shell 2 formed in a cylindrical shape, and drives the gauge ring 7 formed in an annular shape inside the outer shell to move in the direction of tunnel excavation. In a lining casting method using a freely installed shield excavator 1, reinforcing reinforcing bars 21a are placed between the face side end face of the already constructed lining 19 and the gauge ring in the tunnel excavation direction, and one end of the reinforcing bar 21a is Reinforcement reinforcing bars 2 installed during pouring
1a, and the other end is installed movably relative to the gauge ring in the tunnel excavation direction within a reinforcing bar support means such as a guide groove 7a provided in the gauge link, An end stop ring 9 is provided on the reinforcing reinforcing bar so as to be movable in the tunnel excavation direction with respect to the reinforcing reinforcing bar by movement of the gauge ring in the tunnel excavation direction. Concrete placement space 2 between the face side end face
2 is formed, and in that state, concrete 20 is poured into the concrete placement space, and when the concrete is poured and filled, the gauge ring is moved a predetermined distance to the rear of the outer shell. The end stop ring is moved to the rear of the outer shell by a predetermined distance with the reinforcing steel supported within the reinforcing steel support means of the gauge ring, and the movement of the end stop ring causes the concrete to The configuration is such that the concrete poured in the pouring space is pressurized and the concrete is filled into the tail void 26 created by the movement of the outer shell. Pouring space 22
The concrete 20 inside is pressurized, and the tail void 26 is filled with the concrete 20. Therefore, the concrete 20 is densely filled in the concrete placement space 22, and it becomes possible to cast and form the lining 19 efficiently and with high reliability.

Further, the reinforcing reinforcing bars installed in the tunnel excavation direction are installed so as to be movable relative to the gauge ring, and the end stop ring is moved relative to the reinforcing reinforcing bars in the tunnel excavation direction by moving the gauge ring in the tunnel excavation direction. Since the reinforcing bars are movable in the tunnel lining direction, even if the gauge rings and end rings are moved to fill tail voids, there will be no interference between the reinforcing bars and the gauge rings and end rings. Can be installed through the excavation direction. This makes it possible to provide a lining casting method that allows both filling of the tail void with the end stop ring and penetrating installation of a reinforcing member in the tunnel excavation direction to improve the strength of the constructed lining.

[Brief explanation of the drawing]

FIG. 1 is a front sectional view showing an example of a tunnel excavation site to which the lining casting method according to the present invention is applied, and FIGS. 2 to 7 are process diagrams showing an example of the lining casting method according to the present invention. FIG. 8 is a perspective view showing the engagement relationship between the end stop ring and reinforcing reinforcing bars. DESCRIPTION OF SYMBOLS 1... Shield excavator, 2... Outer shell, 9... End stop ring, 19... Lining, 20... Concrete, 21a... Reinforcement bar, 22... Concrete placement space, 26... Tail void.

Claims (1)

[Scope of Claims] 1. Lining using a shield excavator having a cylindrical outer shell and a ring-shaped gauge ring provided inside the outer shell so as to be movable and driveable in the tunnel excavation direction. In the driving method, a reinforcing reinforcing bar is placed in the tunnel excavation direction between the face side end face of the lining that has already been constructed and the gauge ring, and one end of the reinforcing bar is inserted into the end of the reinforcing reinforcing bar that was previously installed. and the other end is installed movably relative to the gauge ring in the tunnel excavation direction within a reinforcing bar support means provided on the reinforcing reinforcing bar, and an end stop ring is attached to the reinforcing reinforcing bar, The gage ring is provided so as to be movable in the excavation direction with respect to the reinforcing reinforcing bars by movement of the gauge ring in the tunnel excavation direction, and furthermore, concrete is placed between the end stop ring and the face-side end surface of the already constructed lining. A concrete placement space is formed, and in that state, concrete is poured into the concrete placement space, and when the concrete is poured and filled, the gauge ring is moved a predetermined distance to the rear of the outer shell. moving the end stop ring to the rear of the outer shell by a predetermined distance with respect to the reinforcing reinforcing bar while the reinforcing steel is supported within the reinforcing steel support means of the gauge ring, and the movement of the end stop ring causes the concrete to A method for placing a lining, comprising pressurizing concrete placed in a placing space and filling the tail void created by the movement of the outer shell with the concrete.