JP2001173396A - Falling object prevention construction in tunnel, falling object prevention method, and falling object preventing member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a falling object prevention construction inside a tunnel capable of preventing the falling of large and small objects with the prevention work carried out easily, a falling object prevention method, and a falling object prevention member. SOLUTION: They comprise netting attached to the surface of concrete lining already formed inside a tunnel and support members penetrating through concrete lining; and they are the falling body prevention construction having netting and support members for concrete masses placed in the natural ground at the rear of concrete lining, anchor devices for support members having anchor holes attached to the netting in addition to their working methods. The feature of the falling object prevention members is that the support member anchor means having anchoring holes for inserting the support members are attached to the netting at predetermined intervals.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a structure for preventing falling objects in a tunnel, a method for preventing falling objects, and a material for preventing falling objects.

[0002]

2. Description of the Related Art The inside of a tunnel is covered with concrete or the like to prevent weathering of the ground or collapse of the ground.
Concrete may be cracked depending on the years of use, the use environment, and the like, and there is a possibility that the separated or separated concrete blocks may collapse. The conventional method for preventing falling objects such as concrete blocks in a tunnel is based on the fact that H
Steel or channel steel is installed along the tunnel circumferential direction.
At predetermined intervals in the tunnel axis direction.

[0003]

There are the following problems in the above-described conventional method for preventing a falling object in a tunnel. <A> H steel and the like are installed at regular intervals. For this reason, there is a danger that concrete blocks and the like that are not supported by H steel or the like may fall. That is, when a small object such as a part of the surface of the concrete lining peels, it cannot be received by the H steel or the like installed at a predetermined interval. <B> The purpose is to prevent falling concrete chunks separated by cracking. For this reason, it does not repair concrete lining.

[0004]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and can be easily constructed, and has a structure for preventing falling objects in a tunnel for preventing falling of large and small objects. It is an object to provide a method and a fall prevention material.

[0005]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention relates to a mesh attached to the surface of a concrete lining already installed in a tunnel, and penetrating the concrete lining. A support member, comprising: a support member of a mesh and a concrete lump, which is cast on the ground behind the concrete lining, and a support member fixing tool having a fixing hole attached to the mesh. It is a structure for preventing falling objects in a tunnel and its construction method. The fallen object preventing member is characterized in that a support member fixing tool having a fixing hole through which the support member is inserted is attached to the mesh at a predetermined interval.

[0006]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded perspective view showing a structure for preventing a falling object in a tunnel according to the present invention.

[0007]

First Embodiment <A> Falling Object Prevention Material The falling object prevention material 1 is a net-like material 11 to which a support member fixing tool 21 described below is attached. Mounting is performed by welding or the like. The number and positions of the attachments vary depending on the required number of support members described below. FIG. 2 shows an embodiment.

<B> Reticulated object The reticulated material 11 has a mesh size enough to prevent occurrence of cracks and the like on the surface of the concrete lining through the reticulated material and to prevent falling objects that hinder use of the tunnel. Have. For example, one having a square mesh having a side length of 5 to 100 mm is used. The net 11 can be made of steel, resin, or the like. For example, wire mesh, expanded metal, perforated plate, etc. can be used. When a corrosive material such as steel is used, the surface can be galvanized to prevent corrosion. Also, if one piece is not strong enough,
Two reticulated objects 11 can be used.

<C> Supporting member fixing device The supporting member fixing device 21 is a perforated plate material. For example, an anchor plate having a fixing hole 22 can be used.
When a corrosive material such as steel is used for the support member fixing tool 21, the surface can be galvanized to prevent corrosion.
The size of the fixing hole 22 is a size through which the support member 2 described below passes.

<D> Support Member The support member 2 is a bar or a wire having a length equal to or greater than the thickness of the concrete lining. For example, lock bolts, reinforcing bars, PC steel strands, and the like can be used.

An embodiment of the method for preventing falling objects in a tunnel according to the present invention will be described below with reference to FIGS.

<A> Installation of Falling Object Prevention Material The falling object prevention material 1 is attached in the circumferential direction of the concrete lining. Attachment of the falling object prevention member 1 is performed by driving the support member 2 described below. Falling object prevention material 1 consisting of mesh material 11
Is lightweight and easy to handle. The falling object prevention member 1 is stretched in the tunnel circumferential direction. For this reason, it is not necessary to install in order from the tunnel entrance, and the installation can be started from any position in the tunnel.

<B> Installation of Support Member The support member 2 is installed from the fixing hole 22. There are two possible methods for placing the support member. The first method is to insert the support member 2 after drilling holes using a leg drill or the like. In the second method, an excavation bit is attached to the tip of the support member 2 and drilling is performed using the bit. Then, the self-drilling method is used in which the support member 2 is installed as it is after the drilling. Cement paste or mortar or the like is injected between the support member 2 and the drilled wall to integrate with the concrete lining and the ground. The concrete lining 4 is supported by the support member 2 driven into the ground.

<C> Fixing of Support Member The end of the support member 2 protruding inside the tunnel is fixed to the support member fixing tool 21 by welding or a nut or the like. As a result, the mesh 11 is supported by the support member 2 via the support member fixing tool 21.

<D> Other methods As another method, the falling object prevention member 1 is temporarily fixed and installed. Thereafter, the support member 2 is cast from the fixing hole 22.

[0016]

Embodiment 2 A gap 6 between the concrete lining 4 and the ground 5
If it is considered that there is, the following method can also be implemented.
Hereinafter, description will be made with reference to FIG.

A gap 6 between the concrete lining 4 and the ground 5
If there is expected to be there, concrete or mortar or cement paste can be filled into the gap. The filling is performed using a drilled hole in which the support member 2 is cast. That is, if the hole 6 in which the support member 2 is cast and the gap 6 communicate, the concrete, mortar, or cement paste can be filled from the hole. In addition, when the position of the gap 6 can be expected, a hole can be separately formed in the concrete lining and a cement paste or the like can be filled from the hole.
If the crack 31 penetrates to the gap 6, the gap 6
The cement paste filled in also enters the cracks 31. As a result, the cracks 31 in the concrete lining are bonded.

[0018]

As described above, the structure for preventing falling objects in the tunnel, the method for preventing falling objects, and the material for preventing falling objects according to the present invention are as described above, and the following effects can be obtained. <B> Install the mesh on the surface of the concrete lining. For this reason, it is possible to prevent a small object from falling such as peeling of the concrete surface. <B> The support member is cast into the ground through the concrete lining. For this reason, it is possible to prevent a large object such as a concrete lump from falling. <C> A mesh material to which a fixing member for a supporting member is attached in advance at a predetermined interval is used. For this reason, the position and the number of the support members to be cast are clear. As a result, the workability is improved and can be used for construction management. <D> Install the mesh on the surface of the concrete lining. For this reason, even after the fall object prevention method is performed, it is possible to observe a state such as a crack on the surface of the concrete lining. <E> If there is a gap between the concrete lining and the ground, a cement paste or the like can be filled. When the crack penetrates to the gap, the cement paste or the like also fills the crack. As a result, the same effect as that obtained by repairing the concrete lining can be obtained.

[Brief description of the drawings]

FIG. 1 is an explanatory view of an embodiment of a falling object prevention structure and a falling object prevention method in a tunnel according to the present invention.

FIG. 2 is an explanatory view of an embodiment of a falling object prevention member.

FIG. 3 is an explanatory diagram of a second embodiment of the present invention.

Claims (5)

[Claims] 1. A mesh member attached to a surface of a concrete lining already installed in a tunnel, and a support member penetrating the concrete lining, the support member being installed on the ground at the back of the concrete lining. A structure for preventing falling objects in a tunnel, comprising: a support member for a net and a concrete block; and a support member fixing tool having a fixing hole attached to the net. 2. A mesh member attached to the surface of a concrete lining already installed in the tunnel, and a support member penetrating the concrete lining, which is installed on the ground behind the concrete lining. A support member for mesh and concrete blocks, a support member fixing tool having a fixing hole attached to the mesh, and a mortar or concrete or cement paste filled in the gap between the concrete lining and the ground, Falling object prevention structure. 3. A mesh member provided with a fixing member having a fixing hole having a fixing hole is stretched in the circumferential direction of the tunnel on the surface of the concrete lining that has already been cast inside the tunnel. Was pierced through the concrete lining and poured into the ground on the back side, wherein one end of the support member was fixed to the support member fixing tool,
How to prevent falling objects in the tunnel. 4. On the surface of the concrete lining that has already been installed inside the tunnel, a mesh member with a support member fixing device having a fixing hole is attached in the circumferential direction of the tunnel, and penetrates from the inside of the tunnel toward the ground. Mortar or concrete or cement paste is filled into the gap between the concrete lining and the ground through the hole, and the mesh and concrete mass support members are passed through the concrete lining to the ground on the back. Casting, fixing one end of the support member to the support member fixing tool,
How to prevent falling objects in the tunnel. 5. A fallen object prevention material, wherein a support member fixing tool having a fixing hole for inserting a support member is attached to a mesh at predetermined intervals.