Tunnel lining method and tunnel lining structure

Abstract

To improve work efficiency of tunnel concrete lining work.SOLUTION: A tunnel lining method includes the steps of: placing concrete C into a first area R1 divided by an inner wall of a tunnel pit 1, one surface 31c of a steel end plank 31A provided at a predefined position of the tunnel pit 1, and an inner periphery concrete form 20 to construct secondary lining concrete 12A; arranging a steel end plank 31B at a position with a prescribed interval to the other surface 31d of the end plank 31; arranging an inner periphery concrete form 20 so as to cause the other end 20b of the inner periphery concrete form 20 to face the end plank 31B by moving the inner periphery concrete form 20 in an axial direction of the tunnel pit 1 after setting the secondary lining concrete 12A; and placing concrete into a second area R2 divided by the inner wall of the tunnel pit 1, the inner periphery concrete form 20, the end plank 31A, and the end plank 31B to construct secondary lining concrete 12B so as to bury the end plank 31A between the secondary lining concrete 12A and the secondary lining concrete 12B.SELECTED DRAWING: Figure 3F

Description

[Technical field]

[0001] The present invention relates to a tunnel lining method and a tunnel lining structure. [Background technology]

[0002] As shown in Patent Document 1, a known tunnel lining method involves fixing a gable plate to the end of a steel form (center), and pouring concrete into the area covered by the inner wall of the tunnel, the center, and the gable plate. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Microfilm of Utility Model Application No. 49-93531 (Utility Model Application No. 47-137027) Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the method disclosed in Patent Document 1, the gable board is removed after the concrete has hardened, which requires additional work time.

[0005] The present invention aims to improve the work efficiency of tunnel concrete lining work. [Means for solving the problem]

[0006] The tunnel lining method of the present invention is a tunnel lining method for constructing secondary lining concrete, i.e., tunnel lining concrete, in sequence in the axial direction of a tunnel inside a tunnel formed by a primary lining concrete constructed by spraying, the method including the steps of pouring concrete into a first region defined by the inner wall of the tunnel, one face of a first steel end plate extending in the circumferential direction of the tunnel and provided at a predetermined position of the tunnel, and an inner circumferential formwork forming a predetermined gap between the inner wall of the tunnel and the first end plate, to construct a first secondary lining concrete, placing a second steel end plate extending in the circumferential direction of the tunnel at a position spaced a predetermined distance from the other face of the first end plate, moving the inner circumferential formwork in the axial direction of the tunnel after the first secondary lining concrete has hardened, and arranging the inner circumferential formwork so that an end of the inner circumferential formwork faces the second end plate, and pouring concrete into a second region defined by the inner wall of the tunnel, the inner circumferential formwork, the first end plate, and the second end plate, to place the first end plate between the first secondary lining concrete and the first end plate. Completely and a step of burying the concrete to construct a second secondary lining concrete.

[0007] The tunnel lining structure of the present invention further comprises concrete poured circumferentially around the inner wall of the tunnel, and steel end plates extending circumferentially around the inner wall of the tunnel and spaced a predetermined distance apart in the axial direction of the inner wall of the tunnel and embedded in the concrete. Effect of the Invention

[0008] According to the present invention, the end plate is not removed and is embedded in the concrete as it is, thereby improving work efficiency. [Brief description of the drawings]

[0009] [Figure 1] 1 is a cross-sectional view of a tunnel according to the present embodiment taken along an axial direction. [Diagram 2] This is a cross-sectional view of a tunnel in the lining process of this embodiment, viewed from the axial direction. [Figure 3A]3 is a partial cross-sectional view taken along line III-III in FIG. 2 of a tunnel in the lining process of this embodiment. [Figure 3B] 3 is a partial cross-sectional view taken along line III-III in FIG. 2 of a tunnel in the lining process of this embodiment. [Figure 3C] 3 is a partial cross-sectional view taken along line III-III in FIG. 2 of a tunnel in the lining process of this embodiment. [Figure 3D] 3 is a partial cross-sectional view taken along line III-III in FIG. 2 of a tunnel in the lining process of this embodiment. [Figure 3E] 3 is a partial cross-sectional view taken along line III-III in FIG. 2 of a tunnel in the lining process of this embodiment. [Figure 3F] 3 is a partial cross-sectional view taken along line III-III in FIG. 2 of a tunnel in the lining process of this embodiment. [Figure 4] FIG. 2 is a front view of the wooden auxiliary gable board of this embodiment. [Diagram 5] 13 is a diagram showing a support structure for an end plate according to a comparative example. FIG. [Figure 6] 13 is a diagram showing a support structure for an end plate according to a comparative example. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.

[0011] The tunnel lining method according to the present embodiment relates to a method for lining with concrete the inner wall 10b of an excavation hole 10a generated by excavating the natural ground 10 when constructing a tunnel T. Specifically, the tunnel lining method according to the present embodiment relates to a secondary lining performed after a primary lining in which concrete is sprayed onto the excavation hole 10a generated by blasting and excavating the natural ground 10 using explosives, or onto the inner wall 10b of the excavation hole 10a generated by excavating the natural ground 10 with an excavator or the like. Hereinafter, the tunnel lining method according to the present embodiment will be specifically described with reference to Figs. 1 to 4.

[0012] In the tunnel lining method of this embodiment, a center 2 (mobile formwork device) (see FIG. 2) for pouring secondary lining concrete is moved a predetermined distance at a time in the axial direction of the tunnel T (axial direction of the excavation hole 10a) to build the secondary lining concrete 12 sequentially in the axial direction of the excavation hole 10a. The secondary lining concrete 12 is formed in a substantially arc shape that follows the shape of the inner wall 11a of the primary lining concrete 11. In the following explanation, the process after the primary lining concrete 11 has already been built by spraying concrete against the inner wall 10b of the excavation hole 10a and the waterproof sheet S has already been attached to the inner wall 11a of the primary lining concrete 11 will be explained. In this embodiment, the hole formed by the primary lining concrete 11 is called a tunnel hole 1.

[0013] First, the center 2 and the inner peripheral form 20 will be described with reference to FIG.

[0014] The center 2 is equipped with wheels (not shown) and is configured to be movable along rails (not shown) laid in the excavation hole 10a. The center 2 can be fixed at any position and is equipped with a hydraulic jack (not shown) that moves the inner peripheral formwork 20 in the radial direction of the tunnel T (radial direction of the excavation hole 10a).

[0015] The inner perimeter formwork 20 is placed with a predetermined gap (space) between it and the inner wall 11a of the primary lining concrete 11 covered with the waterproof sheet S. The inner perimeter formwork 20 has a length in the axial direction of the tunnel T that is approximately the same as that of the secondary lining concrete 12 (see Figs. 3A to 3F). The length of the inner perimeter formwork 20 is, for example, about 10 m, but is not limited to this, and the length of the inner perimeter formwork 20 may be 10 m or more or 10 m or less.

[0016] Next, a specific lining method for the secondary lining concrete 12 will be described. In the tunnel lining method of this embodiment, the same elements such as the secondary lining concrete 12, end plate 31, auxiliary end plate 32, and reinforcing bar 4 are provided in different regions along the axial direction of the tunnel T, so for convenience, the following description will be given by assigning different numbers such as A and B to the same elements such as the secondary lining concrete 12A, the secondary lining concrete 12B, the end plate 31A, and the end plate 31B.

[0017] As shown in Fig. 3A, reinforcing bars 4A to be embedded in secondary lining concrete 12A are placed at predetermined positions. Reinforcing bars 4A improve the rigidity of the tunnel lining body including secondary lining concrete 12A. Reinforcing bars 4A are fixed to fixing members (not shown), which are anchors supported via primary lining concrete 11, for example.

[0018] Next, as shown in Fig. 3A, end plates 3A and 3B are placed at predetermined positions in the tunnel pit 1. End plates 3A and 3B are placed at a predetermined interval in the axial direction of the tunnel pit 1. In this embodiment, secondary lining concrete 12 is poured in order in the direction of arrow Y in Figs. 3A to 3F.

[0019] The end plate 3A is provided on one end 20a side of the inner periphery formwork 20, and covers and partitions the gap between the inner wall 11a of the primary lining concrete 11 covered with the waterproof sheet S and the inner periphery formwork 20. The end plate 3A is used when constructing the secondary lining concrete 12 inside the tunnel including the tunnel entrance. The end plate 3A is provided as a plurality of units along the inner wall 11a of the primary lining concrete 11 in the circumferential direction of the tunnel 1 (not shown). Between the end plates 3A adjacent in the circumferential direction, a sealant or other treatment is provided to prevent the concrete C from leaking out. Note that if the end plates 3A adjacent in the circumferential direction can be arranged in close contact with each other (for example, by welding the adjacent end plates 3A together or fitting the adjacent end plates 3A together), no sealant is required.

[0020] As shown in Fig. 2 and Fig. 3A, the end plate 3B includes a steel end plate 31 extending in the circumferential direction of the tunnel pit 1, and a wooden or steel auxiliary end plate 32 provided on the inner diameter side of the end plate 31 and covering the gap between the inner peripheral end 31a of the end plate 31 and the inner peripheral formwork 20. As shown in Fig. 2, a plurality of end plates 31 are provided in a line along the inner wall 11a of the primary lining concrete 11 in the circumferential direction of the tunnel pit 1. A plurality of auxiliary end plates 32 are provided in a line along the circumferential direction of the tunnel pit 1 so as to overlap the inner peripheral edge of the end plate 31. Between the end plates 31 adjacent in the circumferential direction and between the auxiliary end plates 32 adjacent in the circumferential direction, a sealant or the like is provided to prevent the concrete C from leaking out. Furthermore, if adjacent end plates 31 and adjacent auxiliary end plates 32 can be arranged in close contact with each other (for example, by welding adjacent end plates 31 to each other, or by fitting adjacent end plates 31 and auxiliary end plates 32 to each other), sealing material is not necessary.

[0021] The end plate 31A is fixed to the reinforcing bar 4A via a steel support member 5A. Specifically, one end of the support member 5A is fixed to the reinforcing bar 4A by a bundling member or the like, and is supported by the end plate 31A so as to penetrate the end plate 31A. A male thread is formed on the outer periphery of the support member 5A, and the end plate 31A is fixed in a predetermined position by tightening nuts 6 from both sides of the end plate 31A. However, without being limited to this, the end plate 31A may be fixed to an anchor (not shown) supported by a waterproof sheet S interposed between the inner wall 11a of the primary lining concrete 11 of the tunnel pit 1, or the end plate 31A may be fixed by using both of these means.

[0022] Next, the center 2 (mobile formwork device) (see FIG. 2, etc.) equipped with the inner periphery formwork 20 is moved in the axial direction of the tunnel pit 1 and placed at a position for constructing the secondary lining concrete 12A. Specifically, as shown in FIG. 3A, the inner periphery formwork 20 is placed so that the other end 20b of the inner periphery formwork 20 faces the end plate 31A. Note that the order of the step of moving the center 2 and the step of placing the end plate 3A may be reversed.

[0023] As described above, after the inner perimeter formwork 20 is positioned at the position where the secondary lining concrete 12A is to be constructed, the auxiliary end plate 32A is supported and fixed to the end plate 31A and the inner perimeter formwork 20, as shown in Figure 3A, and is positioned so as to cover the gap between the inner perimeter end portion 31a of the end plate 31A and the inner perimeter formwork 20.

[0024] As shown in Fig. 4, a notch 32a is provided on one end side (end plate 31 side) of the auxiliary end plate 32 (auxiliary end plate 32A), and a notch 32b is provided on the other end side (inner peripheral formwork 20 side) of the auxiliary end plate 32 (auxiliary end plate 32A). As shown in Fig. 3A and other figures, one end of the auxiliary end plate 32A is supported and fixed by fastening a nut 7 with a bolt 31b fixed to the end plate 31A inserted into the notch 32a. The other end of the auxiliary end plate 32A is supported and fixed by being pressed against the side surface of the other end 20b side of the inner peripheral formwork 20 with a bolt 21 fixed to the inner peripheral formwork 20 inserted into the notch 32b and a wedge 8 driven between the bracket 22 attached to the tip of the bolt 21 and the auxiliary end plate 32A.

[0025] In this way, a first area R1 for pouring concrete C (secondary lining concrete 12A) is defined by the inner wall 11a of the primary lining concrete 11 covered by the waterproof sheet S, the side surface of the end plate 3A, the side surface (one face 31c) of the end plate 31A facing the reinforcing bar 4A, the side surface of the auxiliary end plate 32A facing the reinforcing bar 4A, and the inner perimeter formwork 20.

[0026] Next, as shown in Fig. 3B, concrete C is poured into the first region R1. Then, as the concrete C hardens, a tunnel lining including the secondary lining concrete 12A is constructed.

[0027] In the tunnel lining method of this embodiment, as shown in Fig. 3C, reinforcing bars 4B to be embedded in a secondary lining concrete 12B to be constructed next are placed while the concrete C in the first region R1 is hardening. The reinforcing bars 4B are fixed to a fixing member (not shown) that is, for example, an anchor supported via the primary lining concrete 11, like the reinforcing bars 4A.

[0028] Next, as shown in FIG. 3D, a steel support member 5B is fixed to the reinforcing bar 4B, and a side plate 31B is fixed to the support member 5B. The new side plate 31B is disposed at a position spaced apart from the other surface 31d of the side plate 31A that defines the first region R1. The method of fixing the side plate 31B using the support member 5B is the same as the method of fixing the side plate 31A, so a description thereof will be omitted. The predetermined distance is set to be shorter than the axial length of the inner perimeter formwork 20. By setting the distance in this manner, when the concrete C of the secondary lining concrete 12B is poured to construct the tunnel lining body, the inner perimeter formwork 20 and the area where the secondary lining concrete 12A is poured can be overlapped (see FIG. 3E and FIG. 3F). This makes it possible to prevent gaps from occurring between the secondary lining concrete 12A and the secondary lining concrete 12B, or between the secondary lining concrete 12A and the inner perimeter formwork 20, when constructing the secondary lining concrete 12B.

[0029] After the secondary lining concrete 12A in the first region R1 has hardened, the auxiliary end plate 32A is removed. The auxiliary end plate 32A can be easily removed by removing the nut 7 and the wedge 8. At this time, the end plate 31A and the support member 5A are not removed.

[0030] Next, as shown in FIG. 3E, the inner periphery formwork 20 is moved in the axial direction of the tunnel tunnel 1, and the inner periphery formwork 20 is positioned so that the other end 20b of the inner periphery formwork 20 faces the inner periphery end 31a of the end panel 31B.

[0031] 3E, the auxiliary end plate 32B is supported and fixed to the end plate 31B and the inner perimeter formwork 20, and is positioned so as to cover the gap between the inner perimeter end 31a of the end plate 31B and the inner perimeter formwork 20. As a result, a second region R2 for pouring concrete C (secondary lining concrete 12B) is defined by the inner wall 11a of the primary lining concrete 11 covered with the waterproof sheet S, the side surface (other surface 31d) of the end plate 31A, the secondary lining concrete 12A, the inner perimeter formwork 20, the side surface (one surface 31c) of the end plate 31B facing the reinforcing bar 4B, and the side surface of the auxiliary end plate 32B facing the reinforcing bar 4B.

[0032] Next, as shown in Fig. 3F, concrete C is poured in the second region R2. At this time, the concrete C is poured so that the end plate 31A is embedded. Then, as the concrete C hardens, the secondary lining concrete 12B is constructed.

[0033] Thereafter, the same steps are repeated in sequence to sequentially line the tunnel lining including the secondary lining concrete 12 along the axial direction of the tunnel pit 1.

[0034] In this way, in the tunnel lining method of this embodiment, the end plate 31 (end plate 31A) is not removed, but is embedded in the concrete C (secondary lining concrete 12). This shortens the work time required to remove the end plate 31, improving work efficiency. Also, by embedding the end plate 31, the end plate 31 reliably functions as a joint between the secondary lining concretes 12A and 12B.

[0035] In addition, in the tunnel lining method of the present embodiment, the reinforcing bars 4 (reinforcing bars 4B) are placed in a state where the end plate 31 (end plate 31A) is placed. This improves work efficiency compared to, for example, a case where the reinforcing bars 4B are placed after the end plate 31A is removed after the secondary lining concrete 12A is poured.

[0036] In the case where the support members 5A and 5B are not provided, for example, as shown in Figs. 5 and 6, it is possible to provide support members 50 and 150 for supporting the end plate 31A in the area where the secondary lining concrete 12 is next constructed (hereinafter, this area is referred to as the "next construction area"). To be more specific, the support member 50 shown in Fig. 5 has one end 50a fixed to the inner wall 1a of the tunnel 1, and the other end 50b supports the end plate 31A from the side. Also, the support member 150 shown in Fig. 6 has one end 150a fixed to a scaffolding F installed in the next construction area, and the other end 150b supports the end plate 31A from the side. If such a support member 50 or support member 150 is provided, there is a risk that it may interfere with work (such as installation of reinforcing bars 4) to be performed in the next construction area. In contrast, in this embodiment, the support members 5A, 5B that support the end panels 31A, 31B are fixed to the reinforcing bars 4A, 4B embedded in the concrete C. Therefore, there are no members in the next construction area that may hinder work, such as the support member 50 or the support member 150 (scaffolding F), and work efficiency can be improved.

[0037] Furthermore, in the tunnel lining method of this embodiment, the end plate 31 is completely buried in the secondary lining concrete 12, and the end face, which is the inner periphery end 31a of the end plate 31 (the end face on the inner diameter side of the tunnel hole 1), is covered by pouring concrete C. Since the end plate 31 is made of steel, there is a risk of corrosion if the inner periphery end 31a of the end plate 31 is exposed to the outside. Therefore, by completely burying the end plate 31 in the secondary lining concrete 12, it is possible to prevent the end plate 31 from corroding.

[0038] In addition, the inner wall 11a of the primary lining concrete 11 in the above embodiment corresponds to the inner wall of the tunnel in the claims, and the secondary lining concrete 12 corresponds to the tunnel lining concrete in the claims. Also, the secondary lining concrete 12A and the secondary lining concrete 12B in the above embodiment correspond to the first lining concrete in the claims. secondary Lining concrete and second secondaryThe end plate 31A and the end plate 31B correspond to the first end plate and the second end plate in the claims, respectively.

[0039] Although the embodiments of the present invention have been described above, the above-mentioned embodiments merely show some of the application examples of the present invention, and it is not intended that the technical scope of the present invention be limited to the specific configurations of the above-mentioned embodiments.

[0040] In the above embodiment, an example has been described in which reinforcing bars 4A, 4B are embedded in the secondary lining concrete 12A, 12B. However, if the strength of the secondary lining concrete 12A, 12B is sufficiently ensured, it is not necessary to install reinforcing bars 4A, 4B.

[0041] In the above embodiment, an example was described in which the waterproof sheet S was provided, but if the waterproofing of the primary lining concrete 11 is ensured by other waterproofing treatment or the like, the waterproof sheet S does not need to be provided.

[0042] In the above embodiment, the case where the reinforcing bars 4B to be embedded in the secondary lining concrete 12B are placed after the concrete C is poured in the first region R1 has been described, but the present invention is not limited to this. For example, the reinforcing bars 4B may be placed in the second region R2 before the concrete C is poured in the first region R1. Furthermore, the reinforcing bars 4 may also be placed in the region where the secondary lining concrete 12 is to be constructed next to the second region R2 before the concrete C is poured in the first region R1. Furthermore, the end plate 31B may be fixed to the reinforcing bars 4B via the support member 5B before the concrete C is poured in the first region R1. [Explanation of symbols]

[0043] 1. Tunnel 2. Center 3A,3B...Given board 4, 4A, 4B...Reinforced concrete 5,5A,5B...Support member 11. Primary lining concrete 11a...Inner wall 12. Secondary lining concrete 12A Secondary lining concrete (first secondary Lining concrete) 12B Secondary lining concrete (second secondary Lining concrete) 20...Inner perimeter formwork 20a...One end 20b...Other end 31...wife board 31A...Given board (1st gable board) 31B...Given board (2nd gable board) 31a...end 31c...One side 31d...Other side 32,32A,32B...Auxiliary gable board R1...1st area R2...Second area

Claims

1. A tunnel lining method for constructing a secondary lining concrete, which is a tunnel lining concrete, in the axial direction of a tunnel formed by spraying a primary lining concrete, A step of pouring concrete into a first area defined by an inner wall of the tunnel, one surface of a first steel end plate extending in a circumferential direction of the tunnel and provided at a predetermined position of the tunnel, and an inner peripheral formwork forming a predetermined gap between the inner wall of the tunnel and the first secondary lining concrete; A step of disposing a second end plate made of steel extending in a circumferential direction of the tunnel at a position spaced a predetermined distance from the other surface of the first end plate; After the first secondary lining concrete has hardened, the inner periphery form is moved in the axial direction of the tunnel to position the inner periphery form so that an end of the inner periphery form faces the second end panel; a step of pouring concrete into a second area partitioned by the inner wall of the tunnel, the inner perimeter formwork, the first end plate, and the second end plate, and completely embedding the first end plate between the first secondary lining concrete and the second secondary lining concrete to construct a second secondary lining concrete.

2. Before pouring concrete into the second region, a step of providing an auxiliary end plate on the inner diameter side of the second end plate to cover a gap between an end portion on the inner periphery side of the second end plate and the inner peripheral formwork; 2. The tunnel lining method according to claim 1, further comprising the step of removing the auxiliary end plate after the second secondary lining concrete has hardened.

3. 3. A tunnel lining method according to claim 1, further comprising a step of placing reinforcing bars to be embedded in the second secondary lining concrete in the second region before pouring concrete in the first region.

4. A tunnel lining structure having a secondary lining concrete constructed by pouring concrete into a space partitioned by a formwork and a gable plate on the inside of a tunnel formed by a primary lining concrete constructed by spraying, Concrete poured along the circumferential direction of the inner wall of the tunnel; A tunnel lining structure comprising: a plurality of steel end plates extending in the circumferential direction of the inner wall of the tunnel, arranged at predetermined intervals in the axial direction of the tunnel, and completely embedded in the concrete.

5. 5. A tunnel lining structure according to claim 4, wherein the concrete is poured into the inner peripheral end of the end plate.

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