JPH0796880B2 - Tunnel lining method - Google Patents

Description

TECHNICAL FIELD The present invention relates to a tunnel lining method.

<< Conventional Technology >> As is well known, there is a NATM method as a method of lining an excavated tunnel wall with concrete.

The NATM method is a method that uses the strength of the excavated ground as it is. It is constructed by driving rock bolts into the ground and spraying concrete on the excavated surface.

However, in such a lining method, a large amount of concrete sprayed on the excavated surface rebounds and scatters as dust, which considerably deteriorates the work environment, and a countermeasure against it has been strongly demanded.

Therefore, for example, in Japanese Unexamined Patent Publication No. 62-17298, a bending plate form frame is stretched on an excavated tunnel inner cross section through arch support, and the tunnel excavation ground and the bending plate form frame are A lining method of placing concrete in the space has been proposed.

However, the lining method disclosed in this publication also has the technical problems described below.

<< Problems to be Solved by the Invention >> That is, in the lining method disclosed in the above publication, a plurality of metal fittings for nozzle insertion are provided at appropriate places of the bending plate mold, and the metal fittings for concrete placement are provided. Although concrete is injected into the space between the ground and the bending plate formwork by connecting the nozzle, the work of attaching and detaching the metal fitting and the nozzle is complicated, and the metal fitting must be closed after the injection, and this work is also troublesome. Met.

The present invention has been made in view of such conventional problems, and an object thereof is to continuously pour concrete without attaching and detaching the concrete injection pipe. It is to provide a tunnel lining method that can be performed.

<< Means for Solving the Problem >> In order to achieve the above object, the present invention is to install a formwork at a predetermined interval along an excavated wall surface, and between the wall surface and the frame die. In a tunnel lining method for placing concrete, a slit-shaped opening extending in the vertical cross-sectional direction of the wall surface is provided in the formwork, and a fitting for mounting a concrete injection pipe is integrally provided in this opening. The attached slide plate is movably installed, and a thin plate that closes the opening is attached to the slide plate when the slide plate is moved, and the concrete is poured while moving the slide plate along the opening. It is characterized by setting.

<< Advantageous Effects of Invention >> According to the tunnel lining method of the above configuration, when placing concrete, the slide plate is movably installed in the slit-shaped opening extending in the vertical cross-sectional direction of the wall surface formed in the formwork. ,
It is continuously performed by connecting an injection pipe to the metal fitting of the slide plate and moving the slide plate along the opening.

At this time, the opening of the other frame is closed by the thin plate as the slide plate moves, and the leaking of the poured concrete is prevented.

<Example> Hereinafter, a preferred example of the present invention will be described in detail with reference to the accompanying drawings.

1 to 3 show an embodiment of a tunnel lining method according to the present invention.

In the tunnel lining method shown in the figure, first, FIG. 1 (A)
As shown in, the formwork 12 is installed along the excavated wall surface 10 at a predetermined interval d.

The formwork 12 is formed by hinge-connecting four formwork segments 12a to 12d curved to have a predetermined curvature, and is supported by struts (not shown) to form an arch shape.
A plurality of wheels 14 are pivotally attached to the outer ends of the formwork segments 12a and 12d at both ends, respectively, as shown in FIG. 1 (C), and the formwork segments 12a to 12d are inwardly routed from the hinge portion. It is configured so that it can be moved along the rail 16 in the tunnel axis direction when the mold is released by bending.

Further, the U-shaped steel material 18 extending along the width direction is fixedly provided on the outer edges of the mold segments 12a, 12d at both ends of the arch-shaped mold 12, and the steel material 18 has Tubes 20 each of which is enlarged as needed so that a part of the outer periphery thereof abuts the wall surface 10 and prevents the poured concrete from leaking are mounted.

Further, on the front surface of each of the formwork segments 12a to 12d, a U-shaped steel material 18a that becomes an arch shape when connected to each other when assembled.
As shown in FIG. 1 (B), a steel tube 18a is attached to the steel material 18a, which is fixed and is connected in an arch shape, which is enlarged and abuts against the face 22 to prevent concrete from leaking.

On the other hand, in the widthwise central part of the form 12, the second and third parts shown in FIG.
As shown in the figure, a slit-shaped opening 24 extending in the vertical cross-sectional direction of the excavated wall surface 10 is provided.

As shown in FIG. 1 (A), the slit-shaped opening 24 is symmetrical with respect to the central axis of the tunnel.
A pair is formed within a range of a predetermined angle θ, one opening 24, one end side of which is inside the end of the formwork segment 12a, and the other end of which is located inside the formwork segment 12b. The other opening 24 is formed from the inside of the end of the mold frame segment 12c to the inside of the end of the mold frame segment 12d.

The dividing position of the opening 24 does not necessarily have to be set to the position shown in the figure, and may be a position shifted to the left and right.

A slide plate 26 is movably installed in each opening 24.

The slide plate 26 is integrally fixed with a hollow cylindrical metal fitting 28 to which an injection pipe for pouring concrete is mounted, and the slide plate 26 is a guide provided at the inner end of the opening 24. Fitted on rail 30.

On the other hand, on one end side of each opening 24, the formwork segments 12a, 12
A winding shaft 34 supported by a bracket 32 protruding from the d is provided, and a flexible thin plate 36 made of metal or synthetic resin is wound around the winding shaft 34.

Then, on the facing surface of the opening 24, the formwork segments 12a-1
A pair of slit grooves along the opening 24 on the outer surface side of 2d.
38 is formed, and one end of the slit groove 38 has an opening 24
An opening is formed between the end of the thin plate 36 and the winding shaft 34, one end of the thin plate 36 is inserted into the slit groove 38 through this opening, and the end of the thin plate 36 is fixed to the slide plate 26.

Now, when the formwork 12 of the above configuration is installed, each slide plate 26 is positioned on the formwork segment 12a, 12d side of the opening 24, and in this state the concrete injection pipe is connected to the metal fitting 28, respectively. Concrete is poured into the space d between the excavation wall surface 10 and the outer surface of the form 12, while moving each slide plate 26 toward the center of the tunnel cross section.

At this time, the concrete to be poured is mixed with a quick-setting agent to solidify it at an early stage, and compressed air is sent into each of the tubes 20 and a to prevent the poured concrete from leaking.

Then, concrete is placed while moving the pair of slide plates 26 along the guide rails 30 from both ends of the formwork 12 toward the center side, and when the movement within the range of the angle θ is completed, the concrete is placed. When the setting is completed and the cast concrete is hardened, the form 12 is removed from the mold and the next lining is performed.

At this time, as the slide plate 26 moves, the thin plate 36 wound around the winding shaft 34 is unwound, whereby each opening 24
Is closed to prevent concrete from leaking through the opening 24.

Then, when the poured concrete hardens, the injection pipe is removed from the metal fitting 28, the thin plate 36 is wound around the winding shaft 34, the slide plate 26 is moved to the end of the opening 24, and the next lining is prepared. Done.

By the way, according to the tunnel lining method of the above configuration, when pouring concrete, the tip of the injection pipe is attached to the metal fitting 28 fixed to the slide plate 26, and the slide plate 26 is moved along the opening 24. Since this is performed while the fitting pipe is attached to the metal fitting 28, the concrete can be continuously poured without detaching the fitting pipe, and the construction efficiency is greatly improved.

[Brief description of drawings]

FIG. 1 is an explanatory view of a mold used in the tunnel lining method according to the present invention, FIG. 2 is a plan view of an essential part of the mold, and FIG. 3 is a sectional view of an essential part of the mold. 10 …… Wall, 12 …… Formwork 24 …… Opening, 26 …… Slide plate 28 …… Metal fittings, 30 …… Guide rail 36 …… Thin plate

Claims (1)

[Claims] 1. A tunnel lining method in which formwork is installed at a predetermined interval along an excavated wall surface, and concrete is placed between the wall surface and the formwork. A slit-shaped opening extending in the direction of the vertical cross section of the wall is provided, and a slide plate integrally attached with a fitting for mounting a concrete pouring pipe is movably installed in the opening, and the slide plate is also provided. A tunnel lining method, wherein a thin plate that closes the opening is attached to the moving part, and the concrete is placed while moving the slide plate along the opening.