JPH02183095A - Constructing method of tunnel lining - Google Patents

Abstract

PURPOSE:To miniaturize an excavator by movably installing a press ring on the inside of a shell while supporting a forms support member by a jack for excavation, placing concrete and pressing and filling a back-filling material by the press ring. CONSTITUTION:A press ring 7 is mounted movably inside the shell 2 of a shield excavator 1 through a jack 9. A forms support member 11 supporting forms 13 with a back-filling material filling pipe 10 is supported by a jack 6 for excavation. The forms support member 11 is moved forward only by length L1 under the state in which the press ring 7 is projected backward, and the clearance is filled with concrete 21. A back-filling material 31 is injected from the filling pipe 10 while forward shifting the press ring 7. The back-filling material 31 is pressed by the press ring 7 and a tail void formed by the movement of the shell 2 is filled with the material 31. Accordingly, the excavator can be miniaturized.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Industrial Application Field The present invention provides a method for lining a tunnel excavated by a propelling shield using cast-in-place concrete mortar (herein, "concrete mortar" is referred to as "concrete mortar"). , meaning "concrete" or "mortar").

(b), Prior Art FIG. 15 is a diagram showing a conventional tunnel lining construction method.

Conventionally, in order to construct the lining of a tunnel excavated by a shield excavator using cast-in-place concrete, for example, as disclosed in Japanese Patent Application Laid-Open No. 62-194399, a step is required in the process of placing concrete and backfilling material. As shown in FIG. 15, the press ring 42 of the shield excavator 41. Concrete is poured from a concrete supply pipe (not shown) connected to the formwork 13 into an annular concrete placement space 23 surrounded by the gauge ring 11, formwork 13, and stopper 22.
Place mortar 21. Thereafter, while moving the press ring 42 in the direction of arrow A, the backfilling material 31 is passed from the supply hose 45 into the space 43 formed by the movement through the discharge pipe 46 drilled in the press ring 42. By pouring, a lining 47 consisting of concrete/mortar 21 and backfilling material 31 is constructed.

(C) 1 Problem to be Solved by the Invention However, in this method, since the discharge pipe 46 is provided inside the press ring 42, the thickness T2 of the press ring 42 is necessarily the diameter of the discharge pipe 46. It has to be thicker. In addition, the backfilling material 31 cast in the space 43 created by the movement of the press ring 42 is naturally also covered with a thick layer (thickness T
2) will be formed. Then, shield excavator 4
A considerable portion of the inner diameter of the ground 19 excavated in step 1 is occupied by the cylindrical tunnel lining 47 having a thickness of T, and the portion that can actually be used as a tunnel is limited. Conversely, to obtain a given tunnel inner diameter,
The amount of excavation (excavation cross-sectional area) of the ground 19 is considerably larger than that, so the amount of earth and sand excavated by the shield excavator 41 is increased, and the backfilling material 31 to be filled is also required in many places.

SUMMARY OF THE INVENTION In order to solve the above problems, it is an object of the present invention to provide a method for constructing a tunnel lining that can reduce the thickness of the lining by reducing the space created by the movement of the press ring.

(d) Means for solving the zero problem, that is, the present invention has an outer shell (2), and a press ring (7) is provided inside the outer shell (2), so that the press ring (7) is inserted into the outer shell (2). Furthermore, a formwork support member (11) is provided inside the press ring (7) so as to be movable with respect to the outer shell (2), and an excavation jack (6) is provided inside the press ring (7). shell(
When excavating in step 2), a shield was used to drive and propel the excavation jack (6), and when constructing the lining (20), a press ring (7) was made to protrude to the rear of the outer shell (2). In this state, the formwork support member (11) is moved forward of the outer shell (2), and the formwork support member (11) and the formwork (13A) on which concrete and mortar (21) have already been poured are moved.
), a formwork (13B) equipped with a backfilling material injection means (1o) is installed between the concrete casting space (23).
Next, concrete mortar (21) is poured into the concrete casting space (23), and then the press ring (7) is moved toward the outer shell (2) and the press ring ( 7) The space created by the movement of (26
), the backfill material (31) is injected and filled by the backfill material injection means (10), and then the shield excavator (1
), the excavation jack (6) starts moving the outer shell (2) forward, and the press ring (7) is protruded rearward to remove the injected backfill material ( By pressurizing the backfill material (31), the backfill material (
31).

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

(e) 1 Effect With the above-described configuration, the press ring (7) pressurizes the backfill material (31) injected by the backfill compatibility input means (1o) provided in the formwork to form a tail void. (
27), the tail void (27) is reliably filled with the backfilling material (31).

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

FIG. 1 is a front sectional view showing an example of a shield excavator to which the tunnel lining construction method according to the present invention is applied.

Fig. 2 is a sectional view taken along line II-II in Fig. 1, Fig. 3 is a sectional view taken along line II-II in Fig. 1, and Figs. A process diagram showing an example, Fig. 11 is a diagram showing an example of a concrete discharge pipe, Fig. 12 is a countersunk arrow view of the discharge port part of the concrete discharge pipe shown in Fig. 11, and Fig. 13 is a concrete discharge pipe as a backfilling material. Fig. 14 is a diagram showing the results of a compressive strength test of concrete and mortar to which an accelerating agent has been added.

As shown in FIG. 1, the shield excavator 1 has a cylindrical outer shell 2, and the front surface of the outer shell 2, that is, the first
A cutter 3 is rotatably supported on the left side of the figure. The cutter 3 is connected to a drive motor 5 provided on a partition wall 2a of the outer shell 2, which is provided to block the space inside the outer shell 2 in the horizontal direction in the figure. 6 are arranged in a circular ring along the outer shell 2, as shown in FIGS. 1 and 2. The digging jack 6 is provided with a ram 6a that can protrude and retreat in the directions of arrows A and B, and further inside the outer shell 2, a cylindrical press ring 7 is in contact with the inner surface of the outer shell 2. It is slidably provided in the directions of arrows A and B. As shown in FIG. 2, a plurality of press ring jacks 9 are arranged on the press ring 7 at predetermined intervals along the outer shell 2.

By the way, a gauge ring 11 formed in an annular shape is attached to the tip of the ram 6a of the digging jack 6.
The gauge ring 11 has an engagement groove 11a that is connected to the gauge link 1.
1 are formed by perforating each other in an annular shape around the entire circumference.

Further, as shown in FIGS. 2 and 3, the gauge ring 11 is provided with a mold 13 assembled in an annular shape and connected in the left-right direction in FIG. 1. And formwork 1
3 includes a back-fill compatible entry pipe 10 having a cylindrical cross section.
A plurality of injection pipes 1o are detachably provided, and the injection pipe 1o protrudes from the outside of the formwork 13 toward the ground 19, and the discharge port 10a at the tip is connected to the sliding surface of the inner circumferential surface 7b of the preslin tuff. The axes of the respective backfilling compatibility pipes 10 located above are provided radially from the center of the tunnel 15 toward the earth 19 side. The discharge port 10a at the tip of the backfill compatible inlet pipe 10 is formed in such a shape that the discharge port 10a is completely closed when it comes into contact with the inner circumferential surface 7b of the press ring 7.

Moreover, the above-mentioned back-fill compatible entry tube 1o is
463 concrete discharge pipe 32 is backfilling compatible inlet pipe 10
It has an inner diameter sufficient for sliding in the axial direction.

As shown in FIG. 11, the concrete discharge pipe 32 has a concrete conveyance pipe 33, and a concrete pressure pump or the like (not shown) is connected to the concrete conveyance pipe 33. Tip part 33 of concrete conveyance pipe 33
As shown in FIG. 11, a is formed in a shape that is slightly bent upward in the figure, and a cover 35 formed in a cylindrical shape from a flexible material such as rubber is attached to the tip 33a. , are connected so as to cover the outer periphery of the tip portion 33a. The cover 35 extends to the left in FIG. 11, and its tip forms a discharge port 35a having a circular cross section.

Further, a hollow rotating shaft 36 is provided in the concrete conveying pipe 33 so as to be freely rotatable so as to penetrate through the pipe wall 33b of the concrete conveying pipe 33, and is located at a position corresponding to the cover 35 at the tip of the rotating shaft 36. , two stirring blades 36a, 3
6g are provided in a double layer in the directions of arrows C and D, which are the supply directions of the concrete mortar 31. Each stirring g 36 a.

36g has four blades 36b formed at a pitch of 90°, as shown in FIG. 12, and each blade 36b of the stirring blade 36a on the right side of FIG. 11
As shown in the figure, quick-setting agent supply channels 36c and 36d through which the quick-setting agent 30 is supplied are formed so as to communicate with each other.

In addition, on the surface 36e of each blade 36b of the stirring blade 36a,
A large number of quick-setting agent addition holes (not shown) are drilled to communicate the quick-setting agent supply path 36d with the outside.

On the other hand, a drive motor 39 is rotatably provided on the right side of the one-rotation shaft 36 in FIG. Rapid setting agent supply path 36 formed within the shaft 36
It is provided in such a way that it can supply the quick-setting agent 30 to c.

Shield digging! Since the 111 machine 1 has the above configuration, as shown in FIG. 1, and presses the cutter 3 in the direction of the face 16, that is, in the direction of the arrow A, through the partition wall 2a and the outer shell 2. Then, due to the pressing force, the cutter 3 and the face 16 come into contact with each other with a predetermined contact pressure, and the face 16 is excavated by the cutter 3. At the same time, the outer shell 2 is propelled in the direction of arrow A, and the tunnel 15 is moved onto the shield excavator. It is formed at the rear of , that is, to the right in Figure 1.

As the tunnel 15 is formed in this way, it is necessary to construct the lining 20 in order to prevent the excavated earth 19 from collapsing, and the construction of the lining 20 is performed in the following steps. That is, the shield excavator 1
When the ring has been excavated by the length Ll in the direction of the arrow, the bottom \6a of the excavation jack 6 is in the state of protruding in the direction of the arrow B, as shown in Fig. 4, and the press ring 7 has also moved in the direction of arrow B.

In this state, as shown in FIG. 5, the ram 6a of the digging jack 6 is moved back by a distance L1 in the direction of arrow A. Then, the gauge ring 11 is directly connected to the end stop 22A of the part where the concrete/mortar 21 has been poured and the formwork 13A.
moves away and moves in the direction of the arrow, and the end stop 22A and formwork 1
A space having a distance L1 is formed between 3A and the gauge link 11. Therefore, a reinforcing member 12 made of a steel plate, reinforcing bar, etc. is inserted into the engagement groove 11 in the space, as shown by the imaginary line in FIG.
Installed with end stop 22B via a, and further formwork 13A
The formwork 13B is assembled and installed so as to be in contact with. At this time, the discharge port 10 of the backfill compatible entry pipe 10 provided in the formwork 13B
By installing the mold 13B so that a is in contact with the inner circumferential surface 7b of the press ring 7, the discharge port 10a is closed by the press ring 7. and,
The formwork 13B, gauge link 11 (end stop 22B).

A concrete placement space 23 is formed between the press ring 7 and the end stop 22A.

In this state, as shown in Fig. 6, the concrete common supply pipe 2S is connected to the formwork 13B, and the concrete IJJia
Concrete mortar 21 is poured into concrete pouring space 23 through pipe 25.

At this time, the air in the concrete placement space 23A is
Since the air is discharged to the outside through the air vent pipe 13a provided in the formwork 13, the pouring operation of the concrete/mortar 21 in the concrete stroke space 23 is performed smoothly. Furthermore, since the discharge port 10a of the back-filling inlet pipe 10 is closed by the press ring 7, the concrete mortar 21 does not flow into the back-filling inlet pipe 10.

In this way, the concrete mortar 21 has been placed in the concrete placement area 23.

As shown in FIG. 7, the press ring jack 9 is now driven to gradually retreat the press ring 7 in the direction of arrow A. Then, after the press ring 7 has passed, the outer shell 2
A space 26 is formed between the concrete mortar 21 and the poured concrete mortar 21. In addition, the inner peripheral surface 7b of the press ring 7
The discharge port 1 of the backfill compatible inlet pipe 10 which was closed by
0a is opened by the movement of the press ring 7, and the space 2
6 and the inside of the back-filling inlet pipe 10 are connected. Therefore.

A concrete discharge pipe 32 is inserted into the backfill compatible entry pipe 10 from inside the tunnel 15 in the direction of arrow E in the figure. Then, as the press ring 7 moves in the direction of the arrow, the quick-setting concrete/mortar 31 is injected into the space 26 as a backfilling material, and the space 26 is filled with the quick-setting concrete/mortar 31.

To cast quick-setting concrete mortar 31 as a backfilling material through concrete discharge pipe 32, use a concrete pressure pump (not shown) to pour concrete mortar 31 into concrete conveyance pipe 33 of concrete discharge pipe 32 shown in FIG. supply The supplied concrete mortar 31 is, for example, a conventional concrete mortar as shown in FIG. 13, except that the quick-setting agent is omitted. The supplied concrete mortar 31 is transferred to the concrete conveying pipe 3 of the concrete discharge pipe 32.
3. Concrete mortar 31 supplied to concrete conveying pipe 33 of concrete discharge pipe 32
is forcedly fed from the right side in FIG. 11 toward the cover 35, passes between stirring g 36a and 36g, and is cast and supplied into the space 26 from the discharge port 35a, but at this time, the drive motor 39 While being driven to rotate the rotating shaft 36, the quick-setting agent 30 is supplied to the quick-setting agent supply path 36c of the rotating shaft 36 via the quick-setting agent supply pipe 40 and the swivel joint 37. The quick setting agent 30 used here is calcium aluminate (CaO・A1□O1・CaSO
, ) is an aqueous solution. Then, the stirring blade 36 inside the cover 35
a and 36g rotate with the rotation of the rotating shaft 36, and stir the concrete mortar 31 that has been pressure-fed inside the concrete conveying pipe 33 toward the discharge port 35a. Furthermore, stirring blade 3
From the quick setting agent addition hole provided in each blade 36b of 6a,
The quick-setting agent 30 is added and supplied via the quick-setting agent supply channels 36c and 36d, and the added quick-setting agent 3o is added to the concrete mortar 31 and the stirring g36a provided in the double layer.
, 36g, and is discharged to the outside from the discharge port 35a in a uniformly agitated form and placed in the space 26. Although the concrete mortar 31 contains a large amount of aggregate, the cover 35 that covers the outer periphery of the stirring blades 36a and 36g
are made of a flexible material, so the aggregates and the like are attached to the tips 3 of the blades 36b of the stirring blades 36a and 36g.
Even if they are caught between the blades 36f and the cover 35, the cover 35 deforms, so the aggregates etc. will not be caught between the blades 36b and the cover 35, and the stirring blades 36a,
36g of concrete mortar 31 and quick setting agent 30
The stirring operation is performed smoothly.

In this way, the quick-setting concrete mortar 31 to which the quick-setting agent 30 has been added is filled into the space 26 as a backfilling material from the eight backfilling material supply pipes 10 drilled in the formwork 13B. The supply pipe 10 is.

As shown in FIG.
It is done uniformly.

Then, as shown in FIG. 8, when the press ring 7 moves in the direction of the arrow and the side surface 7a almost coincides with the installation position of the end stop 22B on the cage link 11 side, the concrete from the backfill compatibility pipe 10 is removed. -Stop the supply of mortar 31, remove the discharge pipe 32 from the injection pipe 10, and
The inside of the injection pipe is sealed with concrete mortar. Next, as shown in FIG. 9, the ram 6a of the digging jack 6 is
The cutter 3 is driven to project in the direction of arrow B, and the cutter 3 is rotated to start the excavation operation.

Then, as already mentioned, the outer shell 2 starts moving in the direction of the arrow, and after the outer shell 2 moves, a tail void 27 is created between the injected quick-setting concrete mortar 31 and the ground 19. It is formed.

Therefore, as the outer shell 2 moves in the direction indicated by the arrow, the press ring jack 9 is moved backwards to gradually move the press ringer in the direction indicated by the arrow B in synchronization with the movement of the outer shell 2. Then, the uncured quick-setting concrete in the space 26
The mortar 31 is pressed by the press ring 7 and flows to fill the tail void 27. Thus, the 10th
As shown in the figure, when the press ring 7 is moved in the direction of arrow B as the outer shell 2 moves in the six directions of arrows, the tail voids 27 generated as a result of the movement of the outer shell 2 are The mortar 31 is effectively filled. In addition, since the press ring 7 is formed into an annular shape, the quick-setting concrete/mortar 31 is pressed against the entire circumference of the ring with uniform pressure, and therefore the filling operation of the tail void 27 is performed around the entire circumference of the outer shell 2. Both are uniform and in good condition. In this way, when the outer shell 2 is propelled by one link, the press ring 7 has its side surface 7a aligned with the rear end of the outer shell 2, as shown in FIG. Construction is completed with filling of backfill material 31. And, because the filled backfilling material is quick setting concrete mortar 31.

Since it solidifies immediately and covers the periphery of the lining 20, it has a great water-stopping effect, effectively preventing water from entering the concrete/mortar 21 placed on the lining 20 from the ground 19 side, and It becomes possible to maintain the concrete mortar 21 for constructing the concrete mortar 20 in good condition.

Note that the striking surface 29 at this time is formed on a staircase by the movement of the press ring 7, as shown in FIG.

Then, when the quick-setting concrete/mortar 31 has hardened to the extent that the press ring 7 can be moved, construction of the next lining 20 and filling of the concrete/mortar 31 as a backfilling material begins. 10 is removably attached to the formwork 13, so that the formwork 13 for the part of the lining 20 that has been cured is placed in the back-fill compatible entry pipe 1.
0 remains in the lining 20 and is removed, and then moved to the position where the lining 20 is constructed. Then, a new backfill compatible pipe 10 is attached to the formwork 13 and used for constructing the next lining 2o.

The test results of the compressive strength of concrete mortar 31 to which quick-setting agent 3Q has been added are shown in Fig. 14, depending on the addition ratio of quick-setting agent 30. Concrete mortar containing about 10% of 30 reaches a diameter of 13 kg/ad or more one hour after pouring. Usually, with a strength development of about 2 kg/a+,
Since it becomes possible to demold (move the press ring 7), construction of the next lining 2o and filling with quick-setting concrete mortar 31 as a backfilling material can be started, shortening the cycle time of tunnel excavation. You can.

The 28-day strength is comparable to that of ordinary concrete and mortar without the addition of quick-setting agents, and the strength is sufficient for practical use.

It goes without saying that the cleat discharge pipe 32 may not be used and that concrete/mortar without adding an ordinary quick-setting agent may be used to fill it, and that any suitable material other than concrete/mortar may be used. Furthermore, it is also possible to increase the inner diameter of the backfill compatible inlet pipe 10 and use a concrete discharge pipe or the like with a larger outer diameter. Furthermore, in the above-mentioned embodiment, the case was described in which ordinary concrete mortar 21 without adding a quick-setting agent was used for the lining 20.
By using the concrete discharge pipe 32 and using concrete mortar to which an accelerating agent has been added, the lining 2 is
It is also possible to rapidly solidify the concrete mortar 21 placed in the concrete mortar 20, thereby shortening the curing period for the lining 20 portion.

In the above-mentioned embodiment, the concrete mortar 31 to which the quick-setting agent 30 has been added as a backfilling material is filled into the space 26 using the concrete discharge pipe 32. 0 Effects of the Invention As described above, according to the present invention, the press ring 7 is in a state of protruding rearward from the outer shell 2.

A formwork support member such as the gauge ring 11 is moved to the front of the outer shell 2, and a back-fill compatible entry pipe 10 etc. Formwork 13B provided with a backfill compatibility input means.
is installed to form a concrete placement space 23, and then concrete mortar 2 is placed in the concrete placement space.
Thereafter, while moving the press ring 7 forward of the outer shell 2, the backfill material 31 is injected and filled into the space 26 created by the movement of the press ring 7 using the backfill compatible input means. Next, the shield excavator 1 starts digging, and the excavation jack 6 starts moving the outer shell 2 forward, and the press ring 7 is protruded rearward to apply the injected backfill material 31. By applying pressure, the tail void 27 created by the movement of the outer shell 2 is filled with the backfilling material 31.
Since it is not necessary to provide a back-fill compatible means in the press ring 7, the outer diameter of the shield excavator 1 can be reduced by reducing the thickness T1 of the press ring 7 and making the press ring 7 into a tJs type. I can do it.

Therefore, as the thickness T1 of the press ring 7 becomes thinner, the backfill material 31 generated by the movement of the press ring 7
The space 26 to be filled becomes smaller, and the amount of backfilling material 31 required to be cast as a filling member for preventing ground subsidence or a water-stopping member can be reduced. In addition, compared to the case where a backfill compatibility means is provided in the press ring, the amount of excavation of the ground 19 to secure a predetermined tunnel inner diameter can be significantly reduced. Therefore, unnecessary earth and sand excavation work can be omitted, making it possible to significantly shorten the construction period.

[Brief explanation of the drawing]

FIG. 1 is a front sectional view showing an example of a shield excavator to which the tunnel lining construction method according to the present invention is applied, and FIG. 2 is a sectional view taken along the line ■-■ in FIG. Figure 3 is a sectional view taken along the line ■-■ in Figure 1, Figures 4 to 10 are process diagrams showing an example of the method for constructing a tunnel lining according to the present invention, and Figure 11 is an example of a concrete discharge pipe. Figure 12 is a countersunk view of the discharge port of the concrete discharge pipe shown in Figure 11, Figure 13 is a diagram showing an example of the mix of concrete and mortar cast as a backfilling material, Figure 14 15 is a diagram showing the results of a compressive strength test of concrete mortar to which an accelerating agent has been added, and FIG. 15 is a diagram showing a conventional tunnel lining construction method. 23... Concrete placement space 26... Space 27... Tail void

Claims (1)

[Claims] It has an outer shell, a press ring is provided inside the outer shell so as to be movable in the excavation direction of the outer shell, and a form support member is provided inside the press ring relative to the outer shell. A shield is used to drive and propel the excavation jack when excavating the outer shell, and a press ring is made to protrude to the rear of the outer shell when constructing the lining. In this state, the formwork support member is moved to the front of the outer shell, and a mold provided with a backfilling material injection means is placed between the formwork support member and the formwork on which concrete and mortar have already been poured. A frame is installed to form a concrete placement space, then concrete and mortar are poured into the concrete placement space, and then the press ring is moved to the front of the outer shell and the space created by the movement of the press ring is inside,
The backfilling material is injected and filled by the backfilling material injection means, and then the shield excavator starts digging, and the excavation jack starts moving the outer shell forward, and the press ring is projected backward. A method for constructing a tunnel lining comprising: pressurizing the injected backfilling material to fill the backfilling material into a tail void generated by movement of the outer shell.