JP2001262990A - Expansion type support method and support structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an expansion type support method and support structure dispensing with the injection of a back-filling material and allowing a quick construction. SOLUTION: In a steel support method by a liner or H-support expanded and set so as to be closely fitted to a natural ground, a skin plate 13 arranged on the outside of a liner body or H-support body through a bag 12 is pressed to the natural ground 14 by injecting a filler 25 to the bag 12 to complete the liner or H-support.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and a structure for supporting a liner in an excavation method such as a mountain tunnel or an expansion-type steel by an H-shaped tunnel support method, in particular, for tunnel excavation.

[0002]

2. Description of the Related Art Conventionally, supports used for tunnel excavation include H-shaped steel and concrete spraying, tunnel H-shaped supports constructed by combining a main girder and a deck plate, and a liner obtained by assembling a plurality of segments. There are, however, the following two problems in the latter two cases, namely, H-shaped support and liner.

[0003] First, in the case of an H-shaped support, a deck plate is installed between main rings of an annular H-shape which is installed at a predetermined interval in the longitudinal direction of the tunnel. In many cases, the deck plate is installed without expansion. By injecting backfill material into the gap between the deck plate and the ground, the adhesion between the ground and the support was enhanced.

[0004] However, in order to complete the shoring, a two-stage process of installing the shoring and injecting the backfill material is required. Therefore, it takes a long time to complete the shoring and cannot cope with rapid construction. The strength of the shoring is designed under the condition that the shoring is in close contact with the ground. Unnecessary steps such as reinforcing the work were required.

[0005] In addition to the above, H
In the case of form support and using shield jack
When propelling an M (tunnel boring machine), the main girder of the H-shaped support itself moves in the radial direction, and the position of the vertical rib provided between the main girders shifts in the radial direction. was there.

When the liner is assembled inside the ground, a gap is formed between the skin plate of the liner and the ground as in the case of the above-mentioned support, and a backfill material is injected into the gap to fill the ground. Since the adhesiveness between the liner and the liner is increased, there is a problem that it takes time to complete the liner as in the case of the above-mentioned support work.

In addition, in the case of a conventional liner that expands, the inflatable body (bag) is directly pressed against the ground, and even if it has excellent adhesion, it can be used under the condition that the ground and the segment are in close contact with each other. There was a problem that the bearing strength was insufficient.

[0008]

In the conventional tunnel support and liner, a contact means for making close contact with the ground is used.
There were problems to be improved in terms of rapid construction and strength.

An object of the present invention is to provide an expansion-type support method and a support structure that solve the above-mentioned problems.

[0010]

In order to solve the above-mentioned problems, the present invention is configured as follows. A first invention is a steel support method using a liner or an H-shaped support that is expanded and installed so as to be in close contact with the ground,
A skin plate disposed outside the liner body or the H-shaped support body via the expansion means is pressed against the ground by the operation of the expansion means to complete the liner or the H-shaped support.
According to a second aspect of the present invention, in a liner or an H-shaped steel support structure which is installed by being expanded so as to be in close contact with the ground, the expansion is provided outside the liner body or the H-shaped support body via expansion means. A skin plate that can be pressed against the ground by moving to the ground side by means is arranged to form a liner or an H-shaped support.

In the present invention, since the skin plate is pressed against the ground via the expansion means, the liner main body or the H-shaped support main body does not move in the radial direction, and no positional displacement of the vertical ribs or the like occurs. Since the skin plate is in pressure contact with the ground, not the expansion means, it is strong as a fall prevention member for the ground and can uniformly press the entire surface of the ground.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the drawings. 1 to 3 show an embodiment of the present invention. In FIG. 3, a tunnel 3 is excavated while excavating a face 2 by a TBM 1.
The main girder 4 obtained by bending a shaped steel into an arc shape at a predetermined curvature is joined to the joints 5 at both ends thereof by connecting bolts 6 (shown in FIG. 1), so that an annular H-shaped support 7 is provided at a predetermined position in the longitudinal direction of the tunnel. Multiple are built at intervals. A vertical rib 8 having a spacer function for keeping the interval between the H-shaped supports 7 constant is disposed between the H-shaped supports 7 adjacent in the longitudinal direction of the tunnel.

A gripper and a shield jack are disposed in a case 10 of the TBM 1, and the shield jack is extended to extend through a vertical rib 8 so that an H-shaped support 7 at the rear is provided.
TBM1 moves forward by taking a reaction force.

On the upper surface of the outer flange 11 of the main girder 4 which is the main body of the H-shaped support 7, a bag 12 into which a flowing but non-liquid material such as sand or gravel is injected in the tunnel circumferential direction. Multiple arrangements are provided. A skin plate 13 is annularly arranged outside the bag 12, and the skin plate 13
The ground 14 is located outside of the. Here, the skin plate 13 is used as a general term for a deck plate, a wire mesh, a thin plate, an expanded metal (a perforated steel plate) and the like. The skin plate 13 is formed in a ring shape by, for example, slidably overlapping respective ends of a plurality of members divided in a circumferential direction.

The bag 12 does not form an annular shape on the outer periphery of the H-shaped support 7, but as shown in FIG. 1, the H-shaped support 7 is eccentric downward from the center of the tunnel 3. As shown in FIG. 1, a gap 9 is formed between the outer periphery of the ring-shaped H-shaped support 7 and the ground 14, with the maximum width being directly above and the width gradually becoming narrower as going down on both sides. Bags 1 circumferentially separated so as to fill gaps 9 formed in
2 are arranged.

When the bag 12 is contracted, the diameter of the skin plate 13 is reduced, and the bag 12 is filled with an injection material, and the bag 12 expands to expand the skin plate 13.

In the above configuration, a fluid such as sand or gravel is injected into the bag 12, and the bag 12 is expanded by the injection pressure, so that the skin plate 13 is pressed against the ground 14 to prevent its collapse.

The non-liquid fluid to be poured into the bag 12 is preferably a material which solidifies after being poured, such as mortar or concrete, in addition to sand and gravel. This is because these harden after the injection, so that the strength of the bag 12 is not so required, and the reliability of the adhesion between the ground 14 and the skin plate 13 can be increased. Note that the bag 12 is preferably made of a material suitable for the material of the filler to be filled therein.

Further, conventionally, the injection of the backfill material usually includes
Low reliability due to the use of shotcrete,
In the embodiment of the present invention, the mortar or concrete is used for the bag 1.
Since the casting is performed at 2, the same conditions as those of ordinary concrete casting are used, so that the reliability as a support is improved.

In this embodiment, the vertical ribs 8 are used between the H-shaped supports 7.
When the attachment is necessary, the bag 12 presses the skin plate 13 against the ground 14 and the position of the main girder 4 does not change. Therefore, the vertical ribs 8 attached to the main girder 4 are shifted. This does not occur.

[0021]

An embodiment of the present invention will be described with reference to FIG. 4 to 9 show a first embodiment. In the first embodiment,
In the excavation tunnel, an annular H-shaped support 7 is formed by connecting a plurality of main girders 4 of a predetermined curvature made of H-shaped steel in the circumferential direction. As shown in FIG. 4, the H-shaped supports 7 are provided at predetermined intervals in the longitudinal direction of the tunnel,
A bag 12 extending over a predetermined angle in the circumferential direction of the tunnel is placed on the upper surface of the outer flange 11 at
With this bag 12, both end portions 16 of the deck plate 15 as members corresponding to the skin play 13 described in the embodiment are supported on the outer flange 11 of each main girder 4 adjacent in the longitudinal direction of the tunnel. Is configured.

The bag 12 may have only one filling chamber as shown in the embodiment of FIGS.
In the embodiment shown in FIG.
Is partitioned by two partition sheets 18, two gas or liquid storage chambers 19 are formed on the left and right, and one filling chamber 20 is formed between them.
Are pipes 23 and 24 provided with valves 21 and 22, respectively.
Is connected. Therefore, the gas and liquid are injected into the gas or liquid storage chamber 19 by opening and closing the valves 21 on both sides,
Can be discharged. Similarly, the filling material 25 such as mortar and concrete can be injected into the filling chamber 20 by opening and closing the intermediate valve 22.

When the fluid is not injected into each of the chambers 19 and 20, the bag 12 is flattened and deflated as shown in FIG. Expands into a shape as shown in FIG.
In order not to swell, the intermediate portion is in a concave state.) Then, while discharging the gas or liquid from the gas or liquid storage chamber 19, the filling chamber 20 is filled with the filler 25 such as mortar or concrete. I do. At this time, the two partition sheets 18 inside the bag 12 are pushed outward while discharging the gas or liquid in the chamber 19 and come into close contact with the inner wall of the outer bag 17,
The cross-sectional shape at the time of expansion is as shown in FIG. In other words, using the bag 12 with the interior partitioned, the gas or liquid is stored in the chamber 19 in advance, the outer bag 19 is held in the outer shape, and the deck 20 is filled with the filler while the deck play 15 is lifted. By doing so, the filling of the filler 25 can be performed more smoothly and rapidly than in a bag without partitions.

As the bag 12 expands due to the injection of the filling material 25, the deck plate 15 whose both ends 16 are supported by the bag 12 is lifted outward integrally, and its flat deck floor 27 is lifted. Presses against the ground 14.

The deck plate 15 supported by the bag 12
As shown in FIGS. 10A and 10B, a single steel plate having a predetermined length and width is formed by bending to have a deck floor 27 and reinforcing ribs.

That is, the length L between the two ends 18 of the deck floor 27 of the deck plate 15 is equal to that of the annular H-shaped support 7 assembled at a predetermined interval in the tunnel axial direction.
And the width dimension W in the circumferential direction of the tunnel is such that a plurality of deck plates 15 are movably overlapped with each other on both sides 29 thereof. Since it is arranged to be bent at a predetermined curvature over the entire circumference of the annular H-shaped support 7 while being extended in the tunnel circumferential direction, the width dimension W of the deck plate 15 can be set to an arbitrary number over the entire circumference. It is configured to have a size corresponding to the length of one unit when divided into a plurality.

The deck floor 27 is folded inward at a predetermined length L1 at a predetermined interval in the circumferential direction of the tunnel, thereby forming a pleated portion having a substantially T-shaped cross-section with an enlarged diameter portion 30 formed at the end. (This is referred to as a reinforcing rib 28 as described above) and extends in the tunnel axial direction. As shown in FIG. 10A, the reinforcing ribs 28 have inclined portions 31 continuous at both ends, and the front ends approach the lower surfaces of the end portions of the deck floor 27 via the inclined portions 31. The flat end portion 16 is formed by folding as described above.

The deck plate 15 has an annular H-shaped support 67 by arranging its reinforcing ribs 28 in the center direction of the tunnel.
Is supported by the bag 12 provided in the above. Therefore, since the deck floor 27 having a flat surface faces the ground 14, the tunnel support can be constructed so that almost no gap is formed between the deck plate 15 and the ground 14. Moreover, since both ends 16 of the deck plate 15 are movably supported by the bag 12, the deck plate 15 can be securely brought into close contact with the ground 14 by expanding the bag 12. In this way, when the deck plate 15 comes into close contact with the ground 14, the filling of the filler 25 into the bag 12 is stopped, so that the ground load can be supported.

FIGS. 11 and 12 show an example of carrying out an expansion type supporting method according to a second embodiment of the present invention. In the second embodiment, as another example of the tunnel support, instead of the H-shaped support 7 in the first embodiment,
A liner 31 is configured. This liner 31
As shown in FIGS. 13 and 12 as a single body, a channel steel having an outer flange 32 and an inner flange 33 via a web 38 and having joint portions 34 at both ends and bent to a predetermined curvature is used. The main girders 35 are arranged in parallel at predetermined intervals, a connecting plate 36 is erected between the inner flanges 33 of the main girder 35, and the bag 12 is arranged on the upper surface of the outer flange 32. As a member corresponding to the skin plate 13 in the embodiment, a liner face plate 37 having a reinforcing rib 41 is movably arranged on the outer flange 32.

A lining is constructed by combining a plurality of liners 31 in the longitudinal direction of the tunnel and the circumferential direction of the tunnel. As shown in FIG. 11A, the web of the main beam 35 of each liner 31 is arranged in the longitudinal direction of the tunnel. The rear surfaces of the webs 38 are abutted and connected by connecting bolts 39 penetrating between the webs 38. In order to connect in the inner circumferential direction of the tunnel, the joints 34 at both ends of the main girder 35 in each liner 31 are brought into contact with each other, and the connecting bolts are inserted into bolt insertion holes 40 provided in the joints 34, so that each Liner 31
Are connected to complete the lining.

In the second embodiment, the liner face plate 37
Is movably supported on the outer flange 32 of the main girder 35 via the bag 12, so that the bag 12 is filled with a fluid such as sand, gravel, mortar, concrete, and the like, and is expanded. The liner face plate 37 is pushed outward and pressed against and adheres to the ground 14, thereby supporting the ground load and preventing the ground 14 from collapsing.

[0032]

As described above, according to the present invention, since the skin plate is tightly pressed to the ground via the expansion means, it is not necessary to inject a backfill material. Along with this, the completion of the tunnel shoring is completed by the operation of the expansion means, so that the tunnel shoring can be brought into close contact with the ground without a backfill material injection step, which can respond to rapid construction. From the time of expansion, the strength of the shoring can be expected, and it takes a long time to complete the shoring as in the past, and the specified reinforcement was applied during that time, but in the present invention, such reinforcement is unnecessary This has the effect of becoming

[Brief description of the drawings]

FIG. 1 is an explanatory cross-sectional view of a first embodiment.

FIG. 2 is an explanatory sectional view taken along line AA of FIG.

FIG. 3 is an explanatory side sectional view in a tunnel longitudinal direction showing a state where a tunnel is being excavated according to the first embodiment.

FIG. 4 is an explanatory side sectional view of the tunnel supporting structure of the first embodiment, showing a state in which a bag is contracted in a longitudinal direction of the tunnel.

FIG. 5 is an explanatory side sectional view of the bag in an inflated state in the longitudinal direction of the tunnel.

FIG. 6 is a view taken in the direction of the arrow in FIG.

FIG. 7 is a partial perspective view of FIG. 5;

FIG. 8 is an exploded perspective view of the bag before filling with a filler.

FIG. 9 is a cutaway perspective view of the bag in a state after filling with a filler.

10A is a side view of a deck plate, and FIG. 10B is a cross-sectional view taken along line CC of FIG. 10A.

11A is a side sectional view in the longitudinal direction of the tunnel in a state where a bag is contracted, showing the tunnel support according to the second embodiment, and FIG. 11B is a view of the liner alone in FIG. is there.

FIG. 12 is a side view of the liner alone shown in FIG. 11 (B).

FIG. 13 is an explanatory side sectional view in the longitudinal direction of the tunnel in a state where the bag is inflated in FIG. 11 (A).

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 TBM 2 Face 3 Tunnel 4 Main girder 5 Both ends joint part 6 Connecting bolt 7 H type support 8 Vertical rib 9 Gap 10 Case 11 Outer flange 12 Bag 13 Skin plate 14 Ground mountain 15 Deck plate 16 Both ends 17 Outer bag 18 Partition Seat 19 Gas or liquid storage chamber 20 Filling chamber 21 Valve 22 Valve 23 Pipe 24 Pipe 25 Filler 27 Deck floor 28 Reinforcement rib 30 Large diameter section 31 Liner unit 32 Outer flange 33 Inner flange 34 Joint part 35 Main girder 36 Connection plate 37 Liner face plate 38 Web 39 Connecting bolt 40 Bolt insertion hole

Claims (2)

[Claims] 1. A method of supporting a steel liner by means of an expansion liner or an H-shaped support which is installed so as to be in close contact with the ground, and a skin plate arranged via expansion means outside the liner body or the H-shaped support body. Is pressed against the ground by operating the expansion means to complete a liner or H-shaped support. 2. A liner or an H-shaped steel support structure which is installed by being expanded so as to be in close contact with the ground, wherein the expansion means is provided outside the liner body or the H-shaped support body via expansion means. An expansion-type support structure, characterized in that a skin plate that can be pressed against the ground by being moved to the ground side is arranged to form a liner or an H-shaped support.