JPH1037685A - Method and device for supporting tunnel supporting material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently and safely perform replacement work between non- connected supporting material ends, and flexibly cope with the expansion amount varying from one ring to another. SOLUTION: In the tunnel supporting method, supporting material is formed in the form of a ring on which the part between ends is not connected along the inner circumference of a tunnel, the part between the ends is widened to tightly adhere the supporting materials 1, 2 to the ground and mountain, and replaced by concrete to form supporting. A jack 3 is mounted on one end on which the supporting materials 1, 2 are not connected to extend the extension jack 3, and the supporting materials 1, 2 are tightly adhered to the inner circumference of the tunnel. A sheath 4 covering the jack 3 is inserted between its extended ends, a form is set in the circumferential side between the ends to place concrete, and after concrete has prescribed strength, the jack 3 is removed in the sheath 4, which is filled with concrete.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a support material which is formed along the inner periphery of an excavated tunnel in the form of a ring whose ends are not connected to each other, and which is widened between the unconnected ends. The present invention relates to a supporting method and a supporting device for a tunnel supporting material in which a material is brought into close contact with a ground, and the ends thereof are refilled with concrete to form a support.

[0002]

2. Description of the Related Art Conventionally, as a supporting method for supporting an inner peripheral surface of a tunnel excavated by a mechanical excavator or the like, a supporting material is assembled in a closed ring shape, and backing is performed in a gap between the back surface and the ground. There is also an expansion method and the like, or a tunnel liner in which a supporting material is assembled in a ring shape whose ends are not connected, and the end between the ends is widened with a jack or the like to make close contact with the ground.

[0003] In the latter expansion method,
After the jack is widened, there is a work of changing the widened portion with a square pipe or other metal fittings in the gap. However, in the refilling operation, it is necessary to carry out a series of very poor workability steps, such as installation work of a widening jack in a pit, insertion / replacement of a refilling bracket, and removal and removal of the widening jack. Moreover, there is a danger of free fall of the refilling bracket, and there is also a problem in terms of safety.

On the other hand, the applicant has filed Japanese Patent Application No. 8-75.
No. 915 proposes a changing member that prevents free fall.

Here, in the expansion method, since the expansion amount changes for each ring due to the excavation conditions such as the ground conditions and the amount of extra excavation, the dimensions of the rearrangement metal fittings are not constant, and the workability is adjusted according to the site. There is a problem that is bad. On the other hand, there are cases where the conventional technology cannot sufficiently address such a problem.

[0006]

SUMMARY OF THE INVENTION The present invention relates to a method for supporting a tunnel by an expansion method of a tunnel liner, in which a refilling operation between end portions of a supporting material which is not connected can be performed efficiently and safely. It is an object of the present invention to provide a method and an apparatus for supporting a tunnel support material that flexibly corresponds to an expansion amount that changes for each ring of a liner.

[0007]

According to the method of supporting a tunnel support material of the present invention, a support material is formed along the inner periphery of an excavated tunnel into a ring shape in which end portions are not connected to each other, and the connection is performed. In a method for supporting a tunnel supporting material, the supporting material is brought into close contact with the ground by widening the non-connecting ends of the supporting material. A space in which a jack for widening the width between the ends is mounted on one side of the support material and the inside of the support material, and the support material has a hole at an unconnected end where a tip of the jack extends outside. A jack is mounted inside the jack, the jack is extended to make the support material adhere to the inner periphery of the tunnel, and then a means for maintaining the interval between the ends is arranged in place of the jack.

In implementing the method for supporting a tunnel supporting material of the present invention, it is preferable that the means for maintaining the interval between the ends is made of cast-in-place concrete. Then, the cast-in-place concrete inserts a sheath covering the jack between the widened ends, sets a formwork on the inner peripheral side between the ends, places concrete between the ends, and places concrete. It is preferable that the jack is removed by removing the jack in the sheath after the predetermined strength is reached and filling the sheath with concrete.

However, in practicing the present invention, the means for maintaining the interval between the ends arranged in place of the jack is not limited to the above-mentioned cast-in-place concrete, but other means, for example, A refillable metal fitting may be used.

In the tunnel supporting material supporting device of the present invention, the supporting material is formed along the inner periphery of the excavated tunnel into a ring shape in which the ends are not connected, and the unconnected ends are widened. In a tunnel support material supporting device for forming a support by placing a support material in close contact with the ground and refilling the ends thereof with concrete, one of the unconnected end portions of the support material and the support Inside the material, there is a space for installing a jack that widens the gap between the ends and makes the support material adhere to the tunnel, and at the unconnected end there is a hole for the tip of the jack to extend outside It is characterized by:

When the device for supporting a tunnel supporting material according to the present invention is implemented, a sheath inserted between the widened ends so as to cover the jack is set on the inner peripheral side between the ends. It is preferable to have a formwork for casting concrete between the ends. That is, it is preferable that after the jack is widened between the ends, cast-in-place concrete is applied and the jack is removed after the concrete is cured or cured. However, it is also possible to exchange the refilling metal fittings and jacks.

According to the present invention having the above-described structure, a ring-shaped support member whose ends are not connected is provided along the inner periphery of the tunnel, and one end of the support member is supported. A jack mounted inside the material presses the support material at the other end to widen the gap between the ends. As a result, the support material adheres to the ground corresponding to the expansion amount that changes for each ring.

Here, a change in the expansion amount can be dealt with by appropriately adjusting the extension distance of the jack, so that only a single jack is required. In other words, there is no need to prepare a plurality of devices. Since the jack may be a so-called extension jack, a commercially available jack can be used.

When the jack between the ends is covered with a sheath, a mold is set on the inner peripheral side between the ends, and concrete is poured between the ends (when cast-in-place concrete is performed).
After the concrete is hardened, the jack can be removed and diverted, which is economical. If concrete is filled in the sheath after the jack is removed, the ends are integrally connected. Further, it is preferable to set a formwork on the inner peripheral side in the space for mounting the jack and to fill the space for mounting the jack with concrete, since the integration becomes stronger and preferable.

The use of cast-in-place concrete as described above is very economical because there is no need to prepare a plurality of refilling fittings corresponding to the amount of expansion. In other words, there is no need to prepare a large variety of refilling hardware in preparation for fluctuations in the expansion amount.

In the practice of the present invention, when the jack is extended to perform necessary expansion, a concrete casting portion is provided at the base of the jack so that the jack can reliably withstand the reaction force of the expansion. It is preferable to provide them or to provide a reinforcing structure such as a reinforcing rib made of metal, for example.

[0017]

Embodiments of the present invention will be described below with reference to the drawings. Fig. 1 shows a tunnel liner 1 with supporting materials connected along the inner periphery of the excavated tunnel section.
An unconnected top end of 0 is shown. A support member is connected in a ring shape to a lower portion (not shown) of the tunnel liner 10. A widening jack 3 is attached to a support member 1 described below at one end of the top end portion that is not connected, and the jack tip 3 a is in contact with a support member 2 at the other end of the tunnel liner 10.

FIG. 2 shows the jack 3 of the tunnel liner 10.
Is shown the support material 1 at the top end to which is attached. Two main girders 1a, 1a having a U-shaped cross section curved and formed along the inner peripheral shape of the tunnel cross section, and the main girders 1a, 1a are connected at both ends thereof at intervals in the tunnel longitudinal direction. A frame is formed by the joint plates 1b and 1c, and a lath net 5 is stretched on the outer peripheral surface of the curved frame on the back side of the drawing (FIG. 1).
reference).

The lath net 5 is made of a fine mesh for concrete transfer (mesh of about 10 to 15 mm) so that the filled concrete does not flow around.

The joint plate 1b at the end which is not connected
Is provided with a connecting plate 1d connecting the main girders 1a, 1a. A jack 3 for widening is mounted inside the support member 10 (within the thickness of the support member 10) between the connecting plate 1d and the joint plate 1b. The tip 3 of the jack extends through the joint plate 1b.

An embedded concrete 1e is cast in a portion surrounded by the connecting plate 1d between the main girders 1a and 1a and the other joint plate 1c. The embedded concrete 1e is provided to receive the reaction force of the jack 3, and a steel rib (reinforcing rib) may be provided instead of concrete.

Hereinafter, the support method will be described. At a predetermined position of the excavated tunnel, the support material is connected in a ring shape along the inner periphery of the tunnel cross section so that the top ends are at a predetermined interval to form a tunnel liner 10, and the support material 1 at the one end is formed. Of the widening jack 3 attached to the support member 2 at the other end.

Next, when the jack 3 is extended and the tunnel liner 10 is widened, the ring can be brought into close contact with the ground flexibly according to the ground conditions and the expansion amount depending on the excavation conditions for each ring (FIG. 3). . Then, the hard rubber sheath 4 having an incision cut in the circumferential direction is cut into a dimension L between the ends whose width is widened in the longitudinal direction (FIG. 4), the incision of the sheath 4 is opened, and a jack is inserted between the ends. 3
(FIGS. 5 and 6). Further, the connection portion S at the end of the sheath 4 is sealed with a milk seal with a sealant or the like so that the jack 3 does not come into contact with the concrete (FIG. 7).

Then, the form 6 is set on the inner peripheral side between the ends of the tunnel liner, and concrete 7 is poured between the ends (FIG. 8). It is to be noted that, as the concrete 7, an ultra-rapid hardening concrete which develops strength early or an ultra-high-strength concrete is most suitable.

After the concrete 7 has the predetermined strength, the jack 3 is removed and diverted, and the sheath 4 is filled with concrete (mortar). In this way, the end portions are integrally connected, and the shoring is completed.

[0026]

The present invention has the following effects because it is configured as described above.

(1) Since the widening jack is stored inside the tunnel liner, a space for underground work can be secured. (2) Since the structure of the widening jack is not a widening type but a simple push-up type structure, a general extending type jack can be used. (3) Since the jack for widening can be stored in advance outside the tunnel mine, in this case, the complexity of the work inside the mine can be eliminated. (4) It is not necessary to prepare many types of refilling metal fittings in advance, and by configuring the expansion section with concrete (cast-in-place concrete), it is possible to flexibly cope with an expansion amount that differs for each construction site. (5) Since the refilling portion is made of concrete instead of the refillable metal fittings that had a risk of free fall, the refilling portion is in close contact with the ground, and there is no danger of falling off, which is safe. (6) Conventionally, since the expansion portion having a gap by using a square pipe or the like has been filled with concrete and refilled, concrete stones and the like can be prevented from entering from the expansion portion.

[Brief description of the drawings]

FIG. 1 is a drawing showing the top end of a tunnel liner embodying the present invention.

FIG. 2 is a perspective view showing a support member at an end where a jack is mounted.

FIG. 3 is a view showing a widened state.

FIG. 4 is a perspective view showing a sheath.

FIG. 5 is a sectional view of a sheath.

FIG. 6 is a sectional view showing a state where a sheath is opened for insertion.

FIG. 7 is a view showing a state where a sheath is inserted between the ends.

FIG. 8 is a view showing a concrete casting state.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Support material at one end of tunnel liner 1a ... Main girder 1b, 1c ... Joint plate 1d ... Connecting plate 1e ... Concrete filling 2 ... At the other end of tunnel liner Supporting material 3 ... Jack 3 a ... Jack tip 4 ... Sheath 5 ... Lath net 6 ... Formwork 7 ... Concrete 10 ... Tunnel liner

Continued on the front page (72) Inventor Aoyama 1-8 Kanda Nishikicho, Chiyoda-ku, Tokyo Sumitomo Osaka Cement Co., Ltd. Tokyo Branch (72) Inventor Hiroaki Suzuki 1 Kanda Midoridaicho, Chiyoda-ku, Tokyo Sumitomo Osaka Cement Co., Ltd. (72) Inventor Takashi Uno 1-8 Kanda Nishikicho, Chiyoda-ku, Tokyo Sumitomo Osaka Cement Co., Ltd. Tokyo Branch

Claims (5)

[Claims] 1. A support material is formed along the inner periphery of an excavated tunnel into a ring shape in which the ends are not connected, and the width between the unconnected ends is widened so that the support material adheres to the ground. In a method of supporting a tunnel support material, the end portions are replaced with concrete to form a support, wherein the width of the end portion is increased at one of the unconnected ends of the support material and inside the support material. Mounting the jack to extend, the jack is stretched to make the support material adhere to the inner periphery of the tunnel, and then the means for maintaining the interval between the ends is arranged in place of the jack, Support method. 2. The method according to claim 1, wherein the means for maintaining the distance between the ends is made of cast-in-place concrete. 3. The cast-in-place concrete inserts a sheath covering the jack between the widened ends, sets a mold on an inner peripheral side between the ends, and places concrete between the ends. 3. The method of claim 2, wherein after the concrete reaches a predetermined strength, the jack in the sheath is removed and the sheath is filled with concrete. 4. A support material is formed along the inner periphery of the excavated tunnel into a ring shape in which ends are not connected to each other, and the width of the non-connected ends is increased to closely adhere the support material to the ground. In a tunnel support material support device that forms a support by refilling concrete between its ends, one of the unconnected ends of the support material and the inside of the support material positioned at the forefront. Has a space for mounting a jack that widens the gap between the ends to make the support material adhere to the tunnel, and that the unconnected end has a hole for the tip of the jack to extend outside. Characteristic support equipment for tunnel support materials. 5. A mold which has a sheath inserted between the widened ends so as to cover the jack, and is set on the inner peripheral side between the ends to cast concrete between the ends. The tunnel support material supporting device according to claim 4, further comprising a frame.