JP2003106095A - Tunnel inner wall reinforcing structure and method for constructing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tunnel inner wall reinforcing structure which employs corrugated steel products which are advantageous and ensure high safety at the time of repairing an existing tunnel inner wall in service, and to provide a method for constructing the same. SOLUTION: The tunnel inner wall reinforcing structure is comprised of an inverted U-shaped structure and a concrete layer. The inverted U-shaped structure is constructed by combining the corrugated steel products with each other from both the sides, which are each curved inward with a desired curvature over its upper half portion or its entire body according to a tunnel wall which has been subjected to surface preparation at locations to be reinforced, and connecting upper ends of the respective steel products, to thereby obtain an inverted U-shaped structural material, erecting the structural materials in the necessary number side by side, and connecting the structural materials to each other on both the sides thereof over a reinforcement section. The concrete layer is placed between a rear surface of the inverted U-shaped structure as an innermost wall and the existing tunnel wall.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tunnel inner wall reinforcing structure for reinforcing an inner wall surface of an existing tunnel with a corrugated steel material (large deck plate), and a method for constructing the structure.
Here, the corrugated steel material that reinforces the inner wall surface is commercially available as a material for construction / construction and construction in which rolled steel for general structure is bent into a corrugated corrugated product is also stipulated in JIS standard and is easily available. It is possible.

[0002]

2. Description of the Related Art There are many tunnels for railroad tunnels such as Shinkansen and conventional lines, tunnels for exclusive use of automobiles, tunnels for shared use of vehicles, tunnels for hydraulic power plants, and other water canals. The effective cross-sectional area, length, etc. of the tunnel also differ depending on the application and the situation of the construction site. The structure of the tunnel in the mountainous area and the tunnel in the seabed, riverbed, underground, etc.
Excavation method, finishing treatment, etc. are all different. When the amount of excavation is small and the ground is soft in construction, a method of temporarily excavating and lining the wall is also used.

When constructing in a mountainous area, it is necessary to excavate the bedrock, and it is necessary to combine rock drilling work and blasting work. Drilling machines with powerful rotating blades for tunnel drilling are often used. After excavation, supporting work is performed to prevent the collapse of the ground, and then lining work is performed by assembling a formwork, driving in fresh concrete and finishing mortar.

The shield construction method is adopted for tunnels and subsea tunnels in poor ground, and front section excavation is performed by a large-sized drill machine, and lining work is performed immediately after that. In addition to the usual lining work with concrete winding and mortar finishing, for example, in a tunnel such as a subway or an expressway, a method of additionally attaching a cast iron frame material to the inner wall surface is also performed.

[0005] A conventional concrete winding or mortar finishing tunnel has aged deterioration of concrete, fatigue phenomenon of a material to be used due to repeated vibration when passing through a train such as a railway tunnel, especially a high-speed railway tunnel, cracking, and loosening of rebar. Etc. may occur and troubles such as cracks, peeling and collapse may occur. Furthermore, similar damage may occur due to the effects of earthquakes, active fault activities, and ground changes.

[0006] In order to prevent such troubles and damages, frequent and reliable checks are required. However, in long tunnels and tunnels with heavy traffic, frequent checks involve various difficulties. . However, peeling of the inner wall and ceiling of the tunnel may occur during running of high-speed trains and automobiles.
If a collapse occurs, it may cause a catastrophe. In order to avoid such a situation, we will suspend service or regularly patrol through the gap from the end of operation to the start, visual inspection,
As soon as a cracking sound, surface peeling, or other dangerous spots are found by performing a tapping test, etc., repair work is often performed as necessary, but sufficient inspection and monitoring are performed on all of the numerous and long tunnels.・ Repairing is not easy.

Particularly, in train tunnels for Shinkansen trains and tunnels on expressways, which are frequently operated by trains and are severely restricted in terms of working time, vibrations and other adverse effects are large, but The workable time is short, and in the unlikely event that the train or traveling vehicle is directly hit by an oversight, the damage will be enormous.

[0008] In many cases, there are many restrictions on the suspension of operations for such inspection inspections and repair work, and it is often difficult to allocate personnel to ensure safety. Tunnel repair work requires new construction work. Contains different issues.

[0009]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances and uses a corrugated steel material which is advantageous and can ensure a high degree of safety when repairing an inner wall of an existing tunnel in service. An object is to provide a tunnel inner wall reinforcing structure and a construction method thereof.

[0010]

As shown in FIG. 1, a tunnel inner wall reinforcing structure according to the present invention has an upper half portion or an entire portion having a desired curvature in accordance with a tunnel wall 20 whose surface is to be reinforced. Corrugated steel material bent inward by 10
And a reverse U-shaped structural body 12 constituted by connecting the upper end portions of the inverted U-shaped structural materials in parallel by a required number of sets and connecting both sides thereof to each other over a reinforcing section. The U-shaped structure 12 is the innermost wall, and is composed of a concrete layer 18 placed between the rear surface of the U-shaped structure 12 and the existing tunnel wall 20. In this case, for the reason that the repaired portion 22 covers a wide area, or the like, if necessary, the reinforcing bar assembly may be arranged inside the inverted U-shaped structure 12 and then the concrete layer 18 may be appropriately changed. it can. A mortar layer may be used instead of the concrete layer.

In addition, the method for constructing the tunnel inner wall reinforcing structure according to the present invention should be reinforced after removing defective portions and groundwork according to cracks, partial collapses, corrosion of concrete and reinforcing bars of the tunnel inner wall. A required number of sets of inverted U-shaped structural members having upper ends connected to each other by combining corrugated steel materials 10 in which the upper half portion or the whole is bent inward with a desired curvature in accordance with the tunnel wall 20 and connecting the upper end portions are arranged side by side. The reverse U-shaped structure 12 formed over the repair section by being connected to each other is used as a tunnel inner wall side mold, and the reverse U-shaped structure 12 is used as an innermost wall to form a space between the rear surface and the existing tunnel wall 20. Immersed concrete and / or mortar to form a concrete layer on the ground, and the inverted U-shaped structure that functions as the formwork is used as it is as the tunnel inner wall. Characterized in that to exist.

Further, according to the present invention, there can be provided a tunnel inner wall reinforcing structure and a construction method in which the anchor 19 is driven from the corrugated steel material 10 of the inverted U-shaped structure 12 toward an appropriate portion of the inner wall of the existing tunnel. . This makes the inner wall structure of the tunnel stronger. Whether the anchor 19 is driven into the concrete layer 18 or into the natural ground 14 depends on the deterioration condition of the inner wall of the existing tunnel,
Appropriate selection will be made in consideration of the purpose and scale of the tunnel and the nature of the ground.

The corrugated steel material used in the tunnel inner wall reinforcing structure and its construction method according to the present invention and which plays an important role is a rolled steel material for general structure (JIS G-3101).
Compliant with JIS G-3.
352 is a large deck plate as a high-strength construction material that is marketed under the trade name of plank sheet. The plate thickness of the steel plate used as the material for this large deck plate is various from 2.3 mm to 6.0 mm in accordance with the JIS standard, and the height, width, purpose of use, nature of the ground, earth pressure, etc. Corrugated steel materials having appropriate dimensions can be selected according to the above.

The large deck plate needs to be fitted to the inner wall surface of the existing tunnel, but a bending roll machine is used for the bending work, and the bending work is carried out at a desired curvature in accordance with the design dimension of the tunnel to plastically deform it. The inverted U-shaped structure is constructed by appropriately joining a number of the bent members. The number of large deck plates used depends on the size of the opening on the inner wall of the tunnel.
It can be appropriately changed as in the case of four sheets, and in particular, it is possible to consider performing division, connection, joining or the like in consideration of convenience of bending in a factory, storage, transportation and the like.

According to the tunnel inner wall reinforcing structure and the construction method thereof according to the present invention, the inverted U-shaped structure obtained by bending the corrugated steel material having a sufficient strength by itself is used for the concrete pouring mold during the repair construction. It becomes a frame and is firmly fixed to the concrete wall of the existing tunnel by an anchor, and after solidification of concrete, it becomes a new inner wall surface of the tunnel. Therefore, until concrete solidification,
Not only can the trains be put back into service during the so-called curing period, but also cracks and partial collapses of the trains after that, and deterioration of the concrete surface can be prevented.

In this case, the inverted U-shaped structure obtained by bending the corrugated steel material functions as a mold. Therefore, the work cost is low because the work of installing the formwork in the repair work, removing the formwork after solidification of the concrete, finishing the concrete surface after removing the formwork or reworking is unnecessary. Further, it is possible to surely prevent the deterioration and damage of the concrete surface after that, and the safety is remarkably improved. Therefore, considering the cost of patrol inspection that was conventionally required, the cost of materials required for repairing discovered dangerous points, the labor cost, the huge loss due to suspension or suspension of operations such as railways and highways,
As a result, it is economically superior including the effect of improving reliability.

[0017]

DETAILED DESCRIPTION OF THE INVENTION Embodiments of the present invention will be disclosed below with reference to the accompanying drawings. FIG. 1 is a sectional model view showing a tunnel inner wall reinforcing structure according to the present invention. The inverted U-shaped structure 12 is formed by bending a corrugated steel material 10, which is also called a large deck plate, and connecting the opposite upper ends with a connecting member 11. The inverted U-shaped structure 12 is used as a formwork. After use, it is fixed to the existing concrete wall 20, if necessary, to the natural ground 14 by the anchor 19, and is used as it is as the tunnel inner wall without being removed even after the concrete is solidified.

Between the inverted U-shaped structure 12 made of corrugated steel and the ground 14, there is a concrete wall 20 of the existing tunnel. For example, as shown by the hatched portion 22 in FIG. The groundwork is applied in advance to the parts that need repair, including the collapse, defective parts such as corrosion of concrete and rebar, and the surrounding area if necessary.

In the repair work construction, a defective portion such as a crack or a partial collapse of the inner wall of the tunnel is investigated in detail, and necessary groundwork treatment is carried out according to the depth and spread of the defective portion.
When the crack is deep, it is necessary to properly perform the base treatment such as the arrangement of the reinforcing bars. This base treatment is a treatment that removes a portion that may be peeled off or collapsed, and makes it easier to obtain close contact with fresh concrete or mortar that is newly placed.

Then, a concrete layer 18 is formed by pouring fresh concrete and / or mortar into the gap between the inverted U-shaped structure 12 and the ground 14. In this concrete pouring, the nozzle for insertion of fresh concrete is inserted by partially opening the nozzle insertion opening (not shown) provided above the inverted U-shaped structure 12 and the connecting portion at the upper end. Do it.

FIG. 2 schematically shows the main constituent elements and the structural example of the inverted U-shaped structure 12. As shown in FIG. 2 (A), such an inverted U-shaped structure 12 is mainly composed of a corrugated steel material 10 which is also called a large deck plate forming a U-shape (cornered concave and convex groove) having a continuous cross section. And This corrugated steel material 10 was bent so as to have a curvature suitable for the inner wall surface of the tunnel to be formed at least partially or entirely along the groove direction, as in 10A or 10B of FIG. 2B. It is a thing.

Since the corrugated steel material forming the inverted U-shaped structure 12 is a factory operation equipped with a bending apparatus, a required number is prepared in advance. In this case, as a matter of course, consideration should be given to avoiding existing tunnel internal structures such as overhead wire suspension fittings, signal / communication cables, ventilation fans, lighting equipment, ventilation holes, signals / signs by notches and openings. Is. Then, a corrugated steel material bent to a desired curvature is erected on the defective portion subjected to the required base treatment, and the upper portion and the lateral portions are sequentially connected over a repair required section to assemble an inverted U-shaped structure. When fixing the inverted U-shaped structure, anchors are fixed by a required number on the tunnel wall surface at a site where damage or the like does not occur, if necessary.

The inverted U-shaped structure thus assembled functions as a formwork during concrete pouring, and fresh concrete and / or mortar is poured into the gap between the inverted U-shaped structure and the existing tunnel wall. To be done. Then this reverse U
Since the character-shaped structure directly serves as the inner wall of the tunnel, once the pouring of ready-mixed concrete and / or mortar is completed, the operation / passage of trains, vehicles, etc. can be resumed without waiting for the solidification period.

The relationship among the corrugated steel material 10 (inverted U-shaped structure) constructed as described above, the concrete layer 18, the existing tunnel wall 20, the repaired portion 22, and the ground 14 is A- in FIG.
As shown in FIG. 3, which is a cross section taken along the arrow A ′. The left side of the figure is the inside of the tunnel, the right side is the ground 14, and the existing tunnel wall 20 is formed between them.

The existing tunnel wall 20 has a defective portion as shown by hatching, and the defective portion, that is, the repaired portion 22 is subjected to a base treatment. The inverted U-shaped structure 12 is arranged so as to cover the inner wall surface of the tunnel over the repair section of the existing tunnel wall including the repaired portion 22 subjected to the base treatment, and the fresh concrete and / or the mortar are provided in the gap between the two. A cast concrete layer 18 is formed.

[0026]

As described above, according to the inner wall reinforcing structure for a tunnel and the method for constructing the same according to the present invention, a corrugated steel material which is bent in advance in a factory is assembled on site over a repair section of the inner wall to form an inverted U shape. Form a structure and use it as a formwork until concrete or mortar is placed, and after construction use it as a steel tunnel inner wall. With such a steel tunnel inner wall, there is no risk of cracks, collapses, etc. due to aging deterioration such as concrete and mortar walls, and in particular, the anxiety caused by the strength of the adhesive force between the old and new concrete joint surfaces during repair is eliminated, High safety can be maintained for a long period of time.

Further, since the inverted U-shaped structure fulfills the function of the formwork, the work for installing the formwork in the repair work and removing the formwork after the solidification of concrete are not necessary, so that the repair work period can be shortened. The construction cost will be low. Further, according to the present invention, it is possible to improve the safety, shorten the patrol inspection period, reduce the patrol inspection frequency, eliminate frequent repair work, and eliminate the loss caused by the prohibition of tunnel use accompanying inspection and construction. .

The inner wall reinforcing structure for a tunnel using the corrugated steel material according to the present invention can be applied to the entire existing tunnel or a partial repair. Since it is difficult to use the existing tunnels during inspections, repairs, curing, etc., suspension of service such as Shinkansen, high-speed trains, and expressways, suspension of roads, etc. will cause a large economic loss. However, according to the inner wall reinforcing structure and the construction method thereof according to the present invention, the curing period after construction is almost unnecessary and the construction period is substantially shortened.

[Brief description of drawings]

FIG. 1 is a cross-sectional model view showing a basic configuration of an inner wall reinforcing structure for a tunnel according to the present invention.

FIG. 2 is a perspective view (A) showing a shape of a basic material of an inner wall reinforcing structure of a tunnel according to the present invention and an explanatory view (B) of an inverted U-shaped structure.

FIG. 3 is a cross-sectional view taken along the line A-A ′ in FIG.

[Explanation of symbols]

10 Corrugated steel (large deck plate) 11 Connection member 12 Inverted U-shaped structure 14 Ground 18 concrete layers 19 anchor 20 Existing tunnel wall 22 Repair points (base treatment part)

Claims (3)

[Claims] 1. An inverted U-shape in which corrugated steel materials obtained by bending the upper half portion or the whole inward with a desired curvature inward according to a tunnel wall whose surface is to be reinforced is combined and the upper end portions are connected. An inverted U-shaped structure constituted by arranging a required number of sets of structural materials and connecting both sides thereof to each other over a reinforcing section, and the reverse U-shaped structure with the inverted U-shaped structure as the innermost wall and the existing tunnel. A tunnel inner wall reinforced structure comprising a concrete layer cast between the wall and the wall. 2. A desired curvature of the upper half or the whole is adjusted according to the tunnel wall to be reinforced after removing defective parts according to cracks, partial collapse of tunnel inner wall, corrosion of concrete and reinforcing bars, etc. Inverted U in which corrugated steel materials bent inward are combined from the left and right and the upper ends are connected
The inverse U-shaped structure constructed over the repair section by arranging the required number of sets of the U-shaped structural members side by side and connecting both sides of them to each other is used as the tunnel inner wall side frame, As the inner wall, green concrete and / or mortar for forming a concrete layer is placed between the rear surface of the inner wall and the existing tunnel wall, and the inverted U-shaped structure functioning as the formwork remains as the tunnel inner wall. A method for constructing a tunnel inner wall reinforcing structure, characterized by the above. 3. The tunnel inner wall reinforcing structure according to claim 1, wherein an anchor is driven and fixed from the inverted U-shaped structure toward the concrete layer and / or the ground of the existing tunnel wall. And its construction method.