JPH0681592A - Joint structure for segment - Google Patents

Abstract

PURPOSE:To produce the smooth inner face of a tunnel wall body to shorten the term of works, and to secure the sufficient mutual joint strength of segments. CONSTITUTION:A recess 14 is formed on a joint face composed of side faces on the front side of an excavating direction near both the ends of a segment 12. Bolt inserting through-holes 21 which mutually communicate with the recesses 14 of segments being adjacent in a peripheral direction are formed at both the ends of the segment 12. The segment 12 is arranged in the peripheral direction, and a bolt 22 is inserted from the recess 14 through the bolt inserting through hole 21 with the joint end faces 12a of each segment mutually abutted, and a nut 23 is fastened to the bolt 22 for joining the segment 12 in a peripheral direction. A bolt 17 is inserted through an inserting through hole communicating with both the bottom of the recess 14 and a joint face composed of side faces on a rear side in the excavating direction, and fastened with the insert nut of the segment 12 of an existing constructed tunnel wall body 11 to join the segment 12 in an axial direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a joint structure of segments which are connected to form a cylindrical tunnel wall.

[0002]

2. Description of the Related Art In recent years, the tunnel construction method is excavating the ground by a shield machine, and at the rear of it, an arc-shaped segment (made of reinforced concrete or steel).
Are sequentially joined to build a cylindrical tunnel wall,
The so-called shield construction method has become popular.

As shown in FIG. 7, the above-mentioned segments are joined to each other by fitting plate-like joint fittings 2 which are embedded in the joining end faces 1a of the segments (in this case made of reinforced concrete) 1 to be joined to each other with bolts 3 and nuts. 4 is generally used, and a joint recess 5 is formed in advance on the inner surface (concave surface) side of the segment 1 so that the bolts 3 and nuts 4 can be arranged and the fastening operation thereof can be performed. There is.

[0004]

In the joint structure as described above, since the recess 5 is exposed on the inner surface of the tunnel wall body constructed by the segment 1, the work for filling the recess 5 is performed. Has to be carried out, which requires a lot of time and labor for the work, which causes a problem of prolonging the tunnel construction work.

Moreover, the above-mentioned joint structure is used in the segment 1
Since the segments 1 are joined to each other on the inner surface side of the vehicle, in particular, in recent years, the inner diameter of the tunnel is very large, such as a tunnel that accommodates a large amount of traffic or a tunnel that combines a railway and a roadway. When joining segments having a large plate thickness that form a cross-section tunnel, stress is generated, and there is concern about the joining strength.

The present invention has been made in view of the above circumstances, and is for a segment capable of obtaining a smooth inner wall surface of a tunnel wall body to shorten the construction period and ensuring sufficient joint strength. It is intended to provide a joint structure.

[0007]

SUMMARY OF THE INVENTION A segment joint structure of the present invention is a joint structure of a plurality of segments of a tunnel wall body formed by joining rings in an axial direction and joined in a circumferential direction to construct the ring. In the above-mentioned segment, a recess is formed in the side surface near both ends, and a bolt insertion hole that communicates with the recesses of adjacent segments in the circumferential direction is formed, and a bolt inserted into the bolt insertion hole. The segments are joined together in the circumferential direction by a nut fastened to the bolt.

[0008]

According to the segment joint structure of the present invention, the bolts are inserted from the recesses formed on the side surfaces near both ends of the segment into the bolt insertion holes communicating with the recesses of the adjacent segments. Are fastened with nuts, the segments are circumferentially joined to each other. Further, since the recess is formed on the side surface of the segment, it becomes blocked by another segment connected in the axial direction, and the recess is not exposed to the inner surface of the tunnel wall body, so that a smooth inner surface is formed. The tunnel wall body having is obtained. In addition, by forming a recess on the side surface of the segment in the center of the segment in the thickness direction and also forming the position of the bolt insertion hole in the center of the segment in the thickness direction, the joint between the segments can be formed in the thickness of the segment. It is possible to position it in the central portion in the vertical direction.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the segment joint structure of the present invention will be described below with reference to the drawings. In FIG. 1, reference numeral 11
Is a plurality of segments 12, 12 formed in an arc plate shape.
Is a tunnel wall body constructed by connecting rings formed by joining ... in the circumferential direction in the axial direction, and each ring is a segment 1 that constitutes these rings.
.. are joined so that they are staggered in the circumferential direction.

Further, as shown in FIGS. 2 to 4, recesses 14 and 14 are formed in the joint surface (side surface) 13a on the front side in the excavating direction near both ends of the segment 12, and these recesses 14 and 14 are formed. In the bottom parts 14a, 14a of 14,
An insertion hole 15 communicating with the joint surface 13b on the rear side in the excavation direction,
15 are formed.

Further, the joint surface 13a of the segment 12
Are provided with insert nuts 16, 16 in the middle thereof, and bolts 17, 17 are inserted into the insertion holes 15, 15 from the front side in the excavation direction to insert the segment 12 on the rear side in the excavation direction. By being fastened to the nuts 16, 16, ..., These segments 12, 12 ... Are joined together in the axial direction.

In the segment 12, the recess 1 is formed.
4, 14 and the bolt insertion holes 21, 21 ... Communicating with the joint end faces 12a, 12a composed of both ends are formed. As shown in FIG. 5, these bolt insertion holes 21, 21 ,. When the segments 12, 12 are arranged in the circumferential direction and the joining end faces 12a, 12a are brought into contact with each other, the bolt insertion holes 21, 21, ... Of the respective segments 12, 12 ... Communicate with each other. .

The bolts 22, 22 having threaded portions at both ends are inserted from the recesses 14 of the segment 12 on either side into the bolt insertion holes 21, 21 ... Lever bolts 22, 2
Nuts 23, 23 are fastened to both end portions of 2. That is, the respective segments 12, 12 are circumferentially joined by the bolts 22, 22 and the nuts 23, 23.

Next, the procedure for joining the segments 12 will be described. First, in the case of joining the segments 12, 12 ... In the axial direction, on the front side in the excavation direction of the already constructed tunnel wall body 11, with respect to the segments 12, 12, ... The segments 12 are arranged so as to alternate with each other, and the bolts 17, 17 ... Are inserted into the insertion holes 15, 15 ... Of the segment 12, and the bolts 17, 17 ... Are already constructed in the tunnel wall body 11.
Insert nuts 16, 1 of the segments 12, 12 ...
Screw into 6 ... and tighten.

When the segments 12, 12, ... Are joined in the circumferential direction to construct a ring, the segments 12, 12, ...
The joining end faces 12a, 12a ... Of the two 12, 12 ...

In this way, these segment 1
The respective bolt insertion holes 21, 21 ... Of 2, 12 ... Are in communication with each other, and in this state, the bolts 22, 22 ... Are inserted from the recesses 14 of the segment 12 on one side into the bolt insertion holes 21, 21. By fastening the nuts 23, 23 ... To both ends of the bolts 22, 22 ...
Adjacent segments 12, 12 ... Bolts 22, 22
And the nuts 23, 23 are securely joined.

As described above, according to the segment joint structure of the above-described embodiment, the bolts 22 are inserted from the recesses 14 formed in the joint surface 13a formed by the side surface of the segment 12 on the front side in the excavation direction to the bolt insertion holes 21, 21 ... 22 ...
By screwing and fastening nuts 23, 23 ... To these bolts 22, 22, ..., The segments 12, 12, ... Adjacent to each other in the circumferential direction are easily joined.

Since the recesses 14, 14 formed for joining the segments 12, 12 ... In the circumferential direction are formed on the joining surface 13a on the front side in the excavation direction, the recesses 14, 14 are As shown in FIG. 6, it is blocked by another segment 12 joined in the axial direction, and is not exposed to the inner surface side of the tunnel wall body 11. Therefore,
Since it is not necessary to bury the concave portion 5 as in the conventional case, the time and labor required for this burying operation can be reduced,
The work period can be shortened.

Further, the recesses 14, 14 are formed in the central portion in the thickness direction of the segment 12 at the joint surface 13a of the segment 12, and the positions of the bolt insertion holes 21, 21, ... Are also in the central portion in the thickness direction of the segment 12. By forming the segments 12, 12 ...
2 can be located at the central portion in the thickness direction.

Therefore, in particular, in recent years, large-thickness segments forming a large cross-section tunnel having an extremely large inner diameter, such as a tunnel corresponding to a large amount of traffic or a tunnel in which a railway and a roadway are combined, are joined together. In this case, as compared with the conventional joint structure in which the segments are joined together in the vicinity of the inner surface side thereof, the stress is not distorted and the reliable joining strength can be secured.

[0021]

As described above, according to the segment joint structure of the present invention, the following effects can be obtained. Since the recess is formed on the side surface of the segment so as to enable the arrangement of the bolt and the nut and the fastening operation thereof, the recess is closed by another segment that is joined in the axial direction, and the tunnel wall body is formed. Is not exposed to the inner surface of the. Therefore, unlike the conventional case, it is not necessary to bury the concave portion, the time and labor required for the burying operation can be reduced, and the construction period can be shortened.

Further, by forming the concave portion on the side surface of the segment in the central portion in the thickness direction of the segment, and also forming the position of the bolt insertion hole in the central portion in the thickness direction of the segment, the joint portion between the segments can be formed. It can be located at the center of the segment in the thickness direction. Therefore, especially in recent years, tunnels that accommodate a large amount of traffic,
Alternatively, when joining large-thickness segments that form a large cross-section tunnel with an extremely large inner diameter, such as a tunnel that combines a railway and a roadway, close to the inner surface side of the segment as in the conventional joint structure. As compared with one in which the segments are joined together, stress does not tend to be strong, and reliable joining strength can be secured.

[Brief description of drawings]

FIG. 1 is a front view of a part of a tunnel illustrating an embodiment of a joint structure for a segment of the present invention.

FIG. 2 is a front view of a segment for explaining the structure of the segment used in this embodiment.

FIG. 3 is a side view of a segment for explaining the structure of the segment used in this embodiment.

FIG. 4 is a cross-sectional view taken along the line AA of FIG. 1 for explaining a joined state of rings made of segments.

FIG. 5 is a front view of a segment for explaining a joined state of the segments joined in the circumferential direction.

FIG. 6 is a cross-sectional view taken along the line BB of FIG. 1 for explaining a joint portion between rings made of segments.

FIG. 7 is a perspective view of a tunnel inner surface for explaining a conventional segment joint structure.

[Explanation of symbols]

 11 Tunnel Wall 12 Segment 13a Joint Surface (Side) 14 Recess 21 Bolt Insertion Hole 22 Bolt 23 Nut

Claims (1)

[Claims] 1. A joint structure of a plurality of segments, which is joined in a circumferential direction to construct the ring, of a tunnel wall body formed by joining rings in an axial direction, wherein the segment has side surfaces near both ends. A recess is formed, and a bolt insertion hole that communicates with the recesses of adjacent segments in the circumferential direction is formed, and the segments are connected to each other by a bolt inserted into the bolt insertion hole and a nut fastened to the bolt. A joint structure for a segment, wherein the joints are joined in the circumferential direction.