JPH06346695A - Segment for tunnel lining - Google Patents

Abstract

PURPOSE:To make segments for constructing tunnel wall have both advantages of concrete and steel, and to make them suitable for use in sharp curves while being sufficiently strong. CONSTITUTION:A pair of steel main girders 11, stretching in circular arc, are placed in parallel with each other, and both ends thereof are connected respectively with a pair of steel end plates 12 placed facing each other, and thereby a frame body 13 is formed in circular arc shape. Furthermore, reinforcing girders 15, 16 are provided to the inside of the end plates 12 on positions near holes 11a, 12a for insertion of joint bolts B, and concrete 14 is cast into the frame body 13.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a segment for lining a tunnel which is formed by connecting a large number of pieces to form a tunnel wall.

[0002]

2. Description of the Related Art A recent tunnel construction method is a so-called shield construction method in which a cylindrical tunnel wall is constructed by sequentially installing arc-shaped plate segments behind the ground while excavating the ground by a shield machine. It is becoming a target. Segments are roughly divided into concrete and steel, but the shield machine is driven by jacking by reacting the existing segment ring with a reaction force. There is. For example, in the case of a sharp curve, since the shield machine is propelled while turning by taking the reaction force only on the segment outside the curve, the compression force is applied to the outside and the tensile force is applied to the inside by the reaction. . Since concrete is generally strong against compression and weak against tension, we deal with this by installing concrete segments on the outside and steel, which is resistant to tension, on the inside.

By the way, concrete segments are made by placing reinforcing bars in a formwork for concrete placement, and steel segments are made by welding a pair of main girders and end plates made of steel plates to form four sides. By welding the arc plate-shaped skin plate on the outer peripheral surface side,
Each is manufactured. In addition, in the case of connecting segments, it is common to use bolts to connect the fittings on the joint surface in the case of concrete segments and to the main girders and end plates in the case of steel segments. Target

[0004]

By the way, the steeper the curve, the smaller the width of the segment (ring) needs to be, and the joint end face in the tunnel longitudinal direction may be set obliquely as necessary. However, in order to manufacture such a special segment from concrete, it is necessary to renew it from the formwork, which is time-consuming, costly, and inefficient. In this respect, in the case of a steel segment, it is sufficient to assemble the steel plates and integrate them by welding, so it is more advantageous in manufacturing than concrete, but the joint strength becomes insufficient with general bolt connections. In addition, it has a construction inefficiency that requires a secondary lining to fill the inside of the inner surface with concrete after installation.

The present invention has been made in view of the above circumstances, and has the advantages of both concrete and steel, and is particularly suitable for sharply curved portions, and a tunnel with sufficient joint strength can be obtained. The purpose is to provide a lining segment.

[0006]

The tunnel lining segment of the present invention has been made in order to achieve the above object. In claim 1, a pair of steel main girders extending in an arc shape are mutually connected. It is arranged in parallel facing each other, and both ends are
An arc plate-shaped frame body is assembled by connecting with a pair of steel end plates that are opposed to each other in parallel, and the main girder and the end plate have insertion holes for joint bolts at intervals in the longitudinal direction. In a segment for tunnel lining, which is formed by placing a plurality of concrete in the frame body in the longitudinal direction, in the inner surface of the main girder and the end plate, at least at a position close to the insertion hole. It is characterized in that a reinforcing girder extending to the above is fixed, and a joint recess communicating with the insertion hole is formed on the inner side of the reinforcing girder.

According to a second aspect of the present invention, in addition to the reinforcing girder, a reinforcing bar mesh is stretched inside the frame body while being fixed to the main girder and the end plate.

[0008]

According to the tunnel lining segment of the present invention,
It consists of steel main girders and end plates with reinforcing girders fixed to the inner surface, and concrete is placed inside the frame body with reinforced mesh, so both concrete and steel By virtue of the combination of the advantages of: compression in concrete and tensile in steel and reinforced mesh, it has sufficient strength for both forces, which makes it particularly suitable for the sharp bends of tunnels. Further, since the reinforcing girder is close to the insertion hole of the joint bolt, the reinforcing girder receives the coupling force of the joint bolt, and further, there is concrete between the main girder and end plate and the joint recess. Therefore, the joint strength between the segments can be improved.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 4 show a segment 10 according to one embodiment of the present invention. In this segment 10, a pair of steel main girders 11 extending in an arc shape are arranged so as to face each other in parallel with each other, and both ends of the main girders 11 are a pair of end plates made of steel made to face each other in parallel. The structure is such that they are connected to each other by 12 to form an arcuate plate-shaped frame body 13, and concrete 14 is placed inside the frame body 13.
(Note that FIGS. 1 and 2 show a state before the concrete 14 is poured.) In this segment 10, a plurality of segments are connected with the convex surface being the outer surface and the concave surface being the inner surface to form a tunnel wall body. In the main girder 11 and the end plate 12, a plurality of insertion holes 11a, 12a for the joint bolt B are formed at intervals in the longitudinal direction. These insertion holes 11a and 12a are
It is located slightly on the inner surface side of the center of the segment 10 in the thickness direction.

In the segment 10, first, a reinforcing girder 15 is provided over the entire length on the inner surface of the main girder 11 which is close to the insertion hole 11a.
The reinforcing girder 15 extends in a state where the width direction thereof coincides with the width direction of the segment 10 and is curved along the longitudinal direction of the main girder 11, and is fixed to the inner surfaces of the main girder 11 and the end plate 12 by welding. There is.

On the other hand, the inner surface of the end plate 12 has an insertion hole 12a.
A pair of reinforcing girders 16 are provided across the entire length with the pinion sandwiched therebetween. These reinforcing girders 16 extend along the longitudinal direction of the end plate 12 in a state where the width direction thereof coincides with the longitudinal direction of the segment 10, and are fixed to the inner surfaces of the end plate 12 and the main girder 11 by welding. In this case, both ends of the reinforcing girder 16 on the inner surface side overlap with the outer surface side of the reinforcing girder 15 on the main girder side, and this portion is also welded.

In the concrete 14 portion on the inner side of each reinforcing girder 15, 16, the inner surface side of the segment 1 and each insertion hole 11 are formed.
A joint recess 17 that communicates with a and 12a is formed. The joint recess 17 is necessary as a space for fastening the joint bolt B by inserting the joint bolt B into the insertion holes 11a and 12a when the joint bolts B are coupled and connected to each other. Joint recess 17 and insertion hole 11
Concrete 14 exists between a and 12a, and naturally, the concrete 14 in this portion is formed with an insertion hole 17a for inserting a joint bolt which is continuous from the joint recess 17 to the insertion holes 11a and 12a.

A rebar mesh 18 is stretched inside the frame 13. The reinforcing bar mesh 18 is formed by assembling reinforcing bars extending in the lengthwise direction and the widthwise direction of the segment 10 in a grid pattern. When the reinforcing bars extending in the widthwise direction are directed to the inner surface side of the segment 10, the reinforcing bars on the main girder 11 side are reinforced. Digit 15
A portion arranged on the lower surface and in contact with the main girder 11, the end plate 12, and the lower reinforcing girder 16 is fixed by welding. (Note that the reinforcement mesh 18 is omitted in FIG. 1.)

The above is the basic configuration of the present embodiment, and FIGS. 5 and 6 show variations based on the above configuration. In the segment 10A of FIG. 5, the same reinforcing girder 15 is provided in parallel with the reinforcing girder 15 on the outer surface side of the reinforcing girder 16 on the outer surface side of the reinforcing girder 16 on the end plate 12 side. A reinforcing bar mesh 18 similar to the reinforcing bar mesh 18 is stretched on the outer surface side. Further, the segment 10B in FIG. 6 is the reinforcement girder 1 added in the segment 10A.
5. Instead of the reinforcing bar mesh 18, a skin plate 19 forming an outer surface is stretched in a state of being fixed to the main girder 11 and the end plate 12. On the inner surface of the skin plate 19,
As one means for improving the degree of connection with the concrete 14, a dowel 19a is formed in a protruding manner. Other than such a dowel 19a, the inner surface of the skin plate 19 may have a grid-like groove, a ridge, or the like.

Now, the segment 10 (10
According to A, 10B), since the concrete 14 is cast in the steel frame body 13, it has the advantages of both conventional concrete and steel. That is, the compression is received by the concrete 14, and the tension is received by the frame body 13. Further, since the reinforcing girders 15 and 16 are fixed to the inner surface of the frame body 13 and the reinforcing bar mesh 18 is stretched, In particular, the strength against pulling is improved, and thus it is a segment suitable for a sharp curve portion of a tunnel. Moreover, unlike the mere steel segment, the inner peripheral surface is prefinished with concrete 14, so there is also an advantage in construction that does not require a secondary lining.

Since the concrete 14 exists between the main girder 11 and the end plate 12 and the joint recess 17,
Joint bolt B passed through the insertion holes 11a, 12a, 17a
Does not directly contact the main girder 11 or the end plate 12, or only a small contact portion is required, so that the main girder 11, the end plate 12 and the joint bolt B do not affect each other, and the corrosion resistance is high. It is advantageous in terms.

Further, when the segments 10 are connected by the joint bolts B passed through the insertion holes 11a, 12a, 17a, the reinforcing girders 15, 16 are close to the insertion holes 11a, 12a, so that the coupling force of the joint bolt B is increased. Since the reinforcing girders 15 and 16 are to be received, and in addition to this, the concrete 14 is sandwiched between the joint recesses 17 of both the segment joint recesses 10 and the joint bolt B becomes long, so that it is simply the main girder. As compared with the case where the joint bolts 11 are connected to each other and the end plates 12 are connected, the main girder 11 and the end plate 12 are less likely to be distorted, and the joint strength is improved.

In the further manufacturing, the frame 13 is assembled by the main girder 11 and the end plate 12 to which the reinforcing girders 15 and 16 are welded in advance, the reinforcing bar mesh 18 is stretched, and then the concrete 14 is placed inside the frame 13. It suffices to be placed, so that it can be manufactured at low cost without the need for a special mold having a complicated structure.

Further, unlike the mere steel segment, since the inner peripheral surface is prefinished with concrete 14, there is also an advantage in construction which does not require a secondary lining.

[0020]

As described above, according to the segment for tunnel lining of the present invention, the main girder made of steel having the reinforcing girder fixed to the inner surface and the end plate, and further the reinforcing bar mesh is stretched. Since the concrete is placed inside the frame, it has the advantages of both concrete and steel, that is, it has sufficient strength for both compressive and tensile forces. The reinforcing girder is suitable for sharply curved portions, and the reinforcing girder receives the coupling force of the joint bolt because the reinforcing girder is close to the insertion hole of the joint bolt. Since concrete exists between the recesses, the joint strength between the segments can be improved.

[Brief description of drawings]

FIG. 1 is a perspective view of a segment without concrete and reinforcing bar mesh according to an embodiment of the present invention.

FIG. 2 is a plan view of the segment of the embodiment before concrete is poured.

FIG. 3 is a front sectional view of a segment of the embodiment.

FIG. 4 is a partial side sectional view of the segment of the embodiment.

FIG. 5 is a front sectional view of a modified example of the segment of the embodiment.

FIG. 6 is a front sectional view of another modification of the segment of the embodiment.

[Explanation of symbols]

 10, 10A, 10B Segment 11 Main girder 11a, 12a Insertion hole 12 End plate 13 Frame 14 Concrete 15, 16 Reinforcing girder 17 Joint recess 18 Reinforcing bar mesh B Joint bolt

Claims (2)

[Claims] 1. A pair of main girders made of steel extending in an arc shape are arranged in parallel to each other, and both ends thereof are connected by a pair of end plates made of steel, which are opposed to each other in parallel. A tunnel lining structure in which a frame is assembled, a plurality of insertion holes for joint bolts are formed in the main girder and end plate at intervals in the longitudinal direction, and concrete is placed inside the frame. In the working segment, a reinforcing girder extending in the longitudinal direction is fixed to the inner surface of the main girder and the end plate at least at a position close to the insertion hole, and a joint communicating with the insertion hole is provided on the back side of the reinforcing girder. A segment for tunnel linings characterized by having a recess. 2. In addition to the reinforcing girder, inside the frame body,
A segment for tunnel lining, characterized in that a rebar mesh is stretched while being fixed to the main girder and end plate.