JP2954823B2 - Shaft support and tunnel formation method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a tunnel and a shoring for a shaft which is formed by advanced excavation of a part of a section of a tunnel.

[0002]

2. Description of the Related Art Conventionally, in order to support the wall surface of a shaft, a plurality of H-shaped steel materials arranged in a ring along the wall surface of the shaft and a plurality of H-shaped steel materials used as necessary have been penetrated. A support structure consisting of a steel lock bolt extending to the ground is applied.

The shoring is removed when the tunnel section is cut and widened using the shaft.

[0004]

However, the removal of the shoring requires a great deal of labor and time because the H-shaped steel material has a large weight and the H-shaped steel materials are separated by fusing. And require. Further, when the lock bolt is driven in, it takes more labor and time to remove the lock bolt.

[0005] It is an object of the present invention to reduce the labor and time required for tunnel excavation using a shaft.

[0006]

According to the present invention, there is provided a shaft support for a tunnel, which is excavated by a tunnel excavator, which is arranged along a wall of the shaft and has a cloth bag filled with cement milk. At least one segment.

Further, in the tunnel forming method according to the present invention, a tunnel is excavated in the ground, and cement bags are filled with cement milk arranged in a ring along the wall surface to support the tunnel. After installing a shoring including at least one segment and a glass fiber lock bolt penetrating the segment, the shoring is excavated together with the ground with a tunnel excavator to perform cutting.

[0008]

According to the present invention, according to the present invention, the support of a tunnel formed prior to the excavation of the entire cross section of the tunnel is provided with cement milk in a cloth bag arranged in a ring along the wall of the tunnel. At least one filled segment is
Since it is a substance that can be excavated together with the ground by a tunnel excavator, it is unnecessary to remove the support work at the time of cutting and widening using the shaft and the labor and time required for this. it can.

Further, since the glass fiber lock bolt can also be crushed by the tunnel excavator, it is not necessary to pull out the lock bolt at the time of the cutting and spreading, and therefore labor and time for removal are also required. Not.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIGS. 1 and 2, there is shown a tunnel 10 partially excavated in a tunnel section and a shoring 12 applied thereto.

The shoring 12 includes a cement bag 1 and a cloth bag 16 arranged in a ring along the wall surface 14 of the shaft 10.
At least one filled with 8 (four in the example shown)
And prevents the collapse of the wall surface 14.
The illustrated shoring 12 further includes glass fiber lock bolts 22 (see FIGS. 1 and 4) that extend through each segment 20 in the radial direction of the shaft 10 and extend through the ground.

The shaft 10 is, for example, a tunnel machine (TB).
M) Formed by excavating the ground at 24. The supporter 12 sequentially arranges four cloth bags 16 in the circumferential direction on the digging wall immediately after digging the ground by the tunnel digging machine 24 and supports them on the digging wall. Is formed by injecting. When the cement milk solidifies, the cloth bag 16 and the cement milk, which is an injection thereof, become segments 20.

As a support means for supporting each cloth bag 16 on the excavation wall surface, for example, a pair of opposed curved members 26 extending in the circumferential direction of the shaft 10 and extending along the inner peripheral surface of both curved members 26. And a wire net 28. The support means has a ring shape when a plurality of the support means (four in the illustrated example) are connected in the circumferential direction of the shaft 10. According to this supporting means, the bag 16 is placed in the space defined by the two bending members and the wire mesh 28.
And the bag 1 when the cement milk is injected
6 can be restricted to have a flat shape.

The support means can be removed after the cement milk 18 in the bag 16 has solidified. Four ring-shaped segments 20 remaining in contact with each other in the circumferential direction of the shaft 10 and remaining after removal of the support means prevent the collapse of the ground.

As shown in FIG. 3, each bag 16 is, for example, 1.2 m
two rectangular cloths made of cotton and synthetic fiber, having a length of 3.0 m and a width of 3.0 m, which allow water but not the cement milk to overlap, and sew these four peripheral edges A port 30 for injecting the cement milk is provided substantially at the center of the rectangle. Also, the two cloths are threaded at a plurality of locations 32 to limit swelling.

Preferably, the shoring 12 further includes glass fiber lock bolts 22 (see FIGS. 1 and 4) that extend through each segment 20 in the radial direction of the shaft 10 and extend through the ground. By tightening a nut 34 screwed to the end of each lock bolt 22 via a washer or a bearing plate 35, each segment 20
Can be closely attached to the ground.

For example, the lock bolt 22 is inserted into a hole formed by drilling the ground from inside the shaft after the shaft 10 is excavated.
It can be installed by filling the mortar into the hole. Each bag 16 has a hole 36 for allowing the lock bolt 22 to pass therethrough when the bag is placed along the wall surface of the shaft 10.
Is provided.

After the shaft 10 is formed and the shoring 12 is installed, it is cut and spread using, for example, another tunneling machine. Since both the solidified cement milk and the glass fiber can be sheared or cut by the tunnel excavator, the entire cross section of the tunnel is advanced without removing the support 12 while performing the cutting and spreading work while destroying it. Can be excavated.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a shaft.

FIG. 2 is a cross-sectional view of a shaft.

FIG. 3 is a plan view of a cloth bag.

FIG. 4 is a partially enlarged sectional view of a wall surface of a shaft and a shoring.

[Explanation of symbols]

 DESCRIPTION OF REFERENCE NUMERALS 10 shaft 12 support 16 cloth bag 18 cement milk 20 segment 22 lock bolt

Claims (3)

(57) [Claims] 1. A tunnel support comprising at least one segment excavated by a tunnel excavator, the cloth bag being filled with cement milk, arranged in a ring along the wall of the shaft. 2. The shaft support according to claim 1, further comprising a glass fiber lock bolt penetrating the segment. 3. A mine shaft excavated in the ground, and at least one segment formed of a cloth bag filled with cement milk and arranged in a ring shape along the wall surface for supporting the mine shaft, and the segment. A method of forming a tunnel, comprising: installing a support including a glass fiber lock bolt that penetrates the support, excavating the support along with the ground with a tunnel excavator, and performing cutting and widening.