JP7433270B2 - Segment assembly structure - Google Patents

Description

The present invention relates to a segment assembly structure.

As the segments for constructing the cylindrical wall, hexagonal segments are sometimes used (for example, see Patent Document 1). The segments are connected to each other using e.g. long bolts. The bolt is inserted, for example, into an insertion hole that extends through the segment parallel to the oblique side.

Japanese Patent Application Publication No. 5-98897

The above-mentioned segment assembly structure was required to further increase its mechanical strength.

One aspect of the present invention aims to provide a segment assembly structure that can increase mechanical strength.

One aspect of the present invention is a segment assembly structure in which a plurality of segments are combined to form a cylindrical wall body, the segment having a pair of opposing side end surfaces and a pair of V-shapes formed at both ends of the side end surfaces. a plurality of hexagonal-shaped segments each having a pair of inclined end surfaces, and a fastener connecting the plurality of segments, the pair of inclined end surfaces having two inclined end surfaces that are inclined to each other; An insertion hole having an opening in the inclined end surface is formed in one of the circumferentially adjacent segments of the cylindrical wall body, and the fastener is inserted into the insertion hole and protrudes from the opening. The insertion hole is fixed to the other segment at the distal end thereof and has an opening in a region where the cylindrical wall body receives a positive bending moment due to an external force. The present invention provides a segment assembly structure in which the opening is located closer to the inner circumferential surface of the segment than the insertion hole in which the opening is located.

In the assembly structure of the segment, the central axis of the insertion hole, which has the opening in a region where the cylindrical wall body receives a positive bending moment due to an external force, is located closer to the inner circumferential surface than the center line in the thickness direction of the segment. The central axis of the insertion hole, which has the opening in a region where the cylindrical wall body receives a negative bending moment due to an external force, is located closer to the outer circumferential surface than the center line in the thickness direction of the segment. is preferred.

According to one aspect of the present invention, it is possible to provide a segment assembly structure that can increase mechanical strength.

FIG. 2 is a front view showing a cylindrical wall body having a segment assembly structure according to an embodiment. A perspective view of a cylindrical wall. The figure which shows the bending moment of the cross-sectional force in a cylindrical wall body. (A) An end view of a segment having a mounting hole and an insertion hole at an inner peripheral position. (B) A plan view of a portion of the segment viewed from the thickness direction. (A) An end view of a segment having a mounting hole and an insertion hole at an outer circumferential position. (B) A plan view of a portion of the segment viewed from the thickness direction.

[Segment assembly structure]
FIG. 1 is a front view showing a cylindrical wall body having a segment assembly structure according to an embodiment. FIG. 2 is a perspective view of the cylindrical wall. FIG. 3 is a diagram showing the bending moment of cross-sectional force in a cylindrical wall. FIG. 4(A) is an end view of a segment having a mounting hole and an insertion hole at an inner peripheral position. FIG. 4(B) is a plan view of a portion of the segment viewed from the thickness direction. FIG. 5(A) is an end view of a segment having a mounting hole and an insertion hole at an outer circumferential position. FIG. 5(B) is a plan view of a portion of the segment viewed from the thickness direction.

As shown in FIGS. 1 and 2, in the segment assembly structure 10 of the embodiment, a plurality of hexagonal segments 1 are combined to form a tunnel lining portion (cylindrical wall body) T. In FIG. 2, "L" is the axis of the tunnel lining portion T. “F” is the front of the tunnel lining portion T along the axis L. “R” is the rear of the tunnel lining portion T along the axis L.

As shown in FIG. 2, the hexagonal segment 1 has a hexagonal shape when viewed from the thickness direction. The hexagonal segment 1 includes a pair of side end surfaces 1a and a pair of inclined end surfaces 1c. The two side end surfaces 1a are formed to face each other. The two side end surfaces 1a are parallel to each other and have the same length. The pair of inclined end surfaces 1c are formed at both ends of the side end surface 1a, respectively. The pair of inclined end surfaces 1c is comprised of two inclined end surfaces 1b having different angles of inclination with respect to the side end surface 1a, and thus has a V-shape. The two pairs of inclined end surfaces 1c have a V-shape that is convex in the direction away from each other. The inclined end surface 1b is inclined with respect to the side end surface 1a.

The front side end surface 1a of the two side end surfaces 1a is referred to as a "first side end surface 1a1." The rear side end surface 1a of the two side end surfaces 1a is referred to as a "second side end surface 1a2." The front inclined end surface 1b of the two inclined end surfaces 1b constituting the inclined end surface pair 1c is referred to as a "first inclined end surface 1b1." The rear inclined end surface 1b of the two inclined end surfaces 1b constituting the inclined end surface pair 1c is referred to as a "second inclined end surface 1b2." The first inclined end surface 1b1 and the second inclined end surface 1b2 are inclined to each other. The hexagonal segment 1 is also called a honeycomb segment.

The direction connecting the two pairs of inclined end surfaces 1c is the length direction of the hexagonal segment 1. The direction connecting the two side end surfaces 1a is the width direction of the hexagonal segment 1. The hexagonal segment 1 is curved into an arc shape when viewed from the width direction. The hexagonal segment 1 is curved along a cylindrical surface having the axis L as the central axis. The hexagonal segment 1 may be made of reinforced concrete, for example.

The hexagonal segment 1 is in a posture such that its width direction is parallel (or substantially parallel) to the axis L. A plurality of hexagonal segments 1 are combined into a honeycomb shape. On the front end face of the tunnel lining part T in the process of being assembled, the protruding end faces 2 (first side end faces 1a1) of the hexagonal segments 1 and the isosceles trapezoidal recesses 3 are arranged alternately in the circumferential direction of the tunnel lining part T. lined up in The recess 3 is formed by the first side end surface 1a1 of the hexagonal segment 1 and the first inclined end surfaces 1b1 of two hexagonal segments 1 adjacent to this hexagonal segment 1.

The hexagonal segment 1 is incorporated into the tunnel lining part T so as to fit into the recess 3. The second side end surface 1a2 of the newly assembled hexagonal segment 1 is butted against the first side end surface 1a1 of the recess 3. The hexagonal segments 1 whose side end surfaces 1a are butted against each other are lined up along the axis L. The second sloped end surface 1b2 of the newly incorporated hexagonal segment 1 is butted against the first sloped end surface 1b1 of the recess 3. Therefore, the hexagonal segments 1 arranged in the circumferential direction of the tunnel lining portion T are arranged in a staggered manner.

The tunnel lining portion T is, for example, buried underground. External forces are applied to the tunnel lining portion T due to earth and sand, groundwater, etc.

As shown in FIGS. 4(B) and 5(B), a bolt (fastener) 11 is inserted into the hexagonal segment 1 (one segment) from the first side end surface 1a1 to the second inclined end surface 1b2. An insertion hole 5 is formed. The insertion hole 5 may be parallel to the first inclined end surface 1b1.

The opening formed in the first side end surface 1a1 of the insertion hole 5 is referred to as a first opening 5b. The opening formed in the second inclined end surface 1b2 of the insertion hole 5 is referred to as a second opening 5c. An enlarged diameter portion 5a is formed in the insertion hole 5 at a position that includes the first side end surface 1a1. The bottom of the enlarged diameter portion 5a is a locking stepped portion into which the head 11a of the bolt 11 is locked.

A mounting hole 6 is formed in the first inclined end surface 1b1, into which a tip end of a bolt 11 inserted into an insertion hole 5 of another hexagonal segment 1 is mounted. The mounting hole 6 may be provided with an insert anchor (fastening receiver) 7 to which the tip of the bolt 11 is fastened by screwing or the like. For example, a female thread is formed on the inner circumferential surface of the insert anchor 7 to be screwed into a male thread at the tip of the bolt 11.
The mounting hole 6 has an opening 6a in the first inclined end surface 1b1.

The bolt 11 is inserted through the first opening 5b, the tip of the bolt 11 protrudes from the second opening 5c, and is attached to the attachment hole 6. For example, the tip of the bolt 11 is fastened to the insert anchor 7 provided in the mounting hole 6 of the hexagonal segment 1 (the other segment) to be connected by screwing or the like. This fixes the bolt 11 to the adjacent hexagonal segment 1.
Note that the insert anchor 7 may not be provided in the mounting hole 6. In that case, the tip of the bolt 11 can be fixed to the inner peripheral surface of the mounting hole 6.

The bolt 11 includes a head 11a provided at the base end and a shaft 11b extending from the head 11a. The head 11a of the bolt 11 may be a nut screwed onto the base end of the shaft portion 11b. The outer diameter of the shaft portion 11b is smaller than the outer diameter of the head portion 11a.

As shown in FIG. 3, external forces are applied to the tunnel lining portion T mainly from above and below due to earth and sand, underground water, and the like. Therefore, the upper region R1 and the lower region R2 in the tunnel lining portion T receive a positive bending moment. The side region R3, which is the region between the upper region R1 and the lower region R2, is subjected to a negative bending moment.

As shown in FIG. 1, the insertion hole 5 and the mounting hole 6, in which the second opening 5c (see FIG. 4A) and the opening 6a are located in the upper region R1 or the lower region R2, are formed at the inner peripheral position P1. . As shown in FIG. 4(A), "the insertion hole 5 and the mounting hole 6 are formed at the inner peripheral position P1" means that the central axis of the insertion hole 5 and the central axis of the mounting hole 6 are It is said that the position is closer to the inner circumferential surface 1d of the hexagonal segment 1 than the center line C of the hexagonal segment 1.

As shown in FIG. 1, the insertion hole 5 and the mounting hole 6, in which the second opening 5c (see FIG. 5(A)) and the opening 6a are located in the side region R3, are formed at an outer peripheral position P2. As shown in FIG. 5(A), "the insertion hole 5 and the mounting hole 6 are formed at the outer peripheral position P2" means that the central axis of the insertion hole 5 and the central axis of the mounting hole 6 are in the thickness direction. This means that it is located closer to the outer circumferential surface 1e of the hexagonal segment 1 than the center line C.

As shown in FIG. 1, the six hexagonal segments 1 exposed on the front end surface of the tunnel lining portion T are referred to as hexagonal segments 1A to 1F clockwise. Since the hexagonal segment 1A in the uppermost position is entirely located in the upper region R1, the second opening 5c and the opening 6a are located in the upper region R1. Therefore, the insertion hole 5 and the mounting hole 6 are located at the inner peripheral position P1 (see FIG. 4(A)).

Regarding the hexagonal segments 1B and 1F adjacent to the hexagonal segment 1A, the second opening 5c and the opening 6a formed in one inclined end surface 1b in the length direction (circumferential direction of the tunnel lining portion T) are located in the upper region. It's in R1. Therefore, the insertion hole 5 and the mounting hole 6 are located at the inner peripheral position P1 (see FIG. 4(A)).

The second opening 5c and the opening 6a formed in the other inclined end surface 1b in the length direction are located in the side region R3. Therefore, the insertion hole 5 and the mounting hole 6 are located at the outer peripheral position P2 (see FIG. 5(A)).

Regarding the hexagonal segments 1C and 1E, the second opening 5c and the opening 6a formed in one inclined end surface 1b in the length direction (circumferential direction of the tunnel lining portion T) are located in the lower region R2. Therefore, the insertion hole 5 and the mounting hole 6 are located at the inner peripheral position P1 (see FIG. 4(A)).

The second opening 5c and the opening 6a formed in the other inclined end surface 1b in the length direction are located in the side region R3. Therefore, the insertion hole 5 and the mounting hole 6 are located at the outer peripheral position P2 (see FIG. 5(A)).

Since the hexagonal segment 1D located at the lowest position is entirely located in the lower region R2, the second opening 5c and the opening 6a are located in the lower region R2. Therefore, the insertion hole 5 and the mounting hole 6 are located at the inner peripheral position P1 (see FIG. 4(A)).

As shown in FIGS. 4(A) and 5(A), the insertion hole 5 and the mounting hole 6 in which the second opening 5c and the opening 6a are located in the upper region R1 or the lower region R2 are It is located closer to the inner circumferential surface 1d of the hexagonal segment 1 than the insertion hole 5 and mounting hole 6 in the side region R3.

[How to assemble segments]
As shown in FIG. 2, the protruding end surface 2 (first side end surface 1a1) of the hexagonal segment 1 and the isosceles trapezoidal recess 3 are located on the front end surface of the tunnel lining portion T in the process of being assembled. They are arranged alternately in the circumferential direction of portion T. A new hexagonal segment 1 is assembled into the recess 3 in a direction parallel to the axis L using a shield machine.

As shown in FIGS. 4(B) and 5(B), the bolt 11 inserted into the insertion hole 5 is rotated around the axis using a fastening device of a shield machine, and the tip of the shaft portion 11b is inserted into the insert anchor 7. shall be concluded. Thereby, the bolts 11 connect circumferentially adjacent hexagonal segments 1 of the tunnel lining portion T.

The segment assembly structure 10 can be applied to, for example, road tunnels, railway tunnels, public ditches, sewers, waterworks, underground rivers, storage pipes, and the like.

[Effects produced by the segment assembly structure of the embodiment]
In the segment assembly structure 10, the insertion hole 5 in which the second opening 5c is located in the upper region R1 or the lower region R2 is located in the inner part of the hexagonal segment 1 compared to the insertion hole 5 in which the second opening 5c is located in the side region R3. It is located close to the circumferential surface 1d. Therefore, high strength can be given to the tunnel lining portion T in the upper region R1 and the lower region R2 that receive a positive bending moment. Furthermore, high strength can be imparted to the tunnel lining portion T in the side region R3 that receives a negative bending moment. In this way, by determining the position of the insertion hole 5 in the segment thickness direction according to the bending moment that the tunnel lining portion T receives, the durability of the tunnel lining portion T can be increased. Further, since high strength can be imparted to the tunnel lining portion T, it is advantageous in terms of making the hexagonal segment 1 thinner and lighter.

The insertion hole 5 in which the second opening 5c is located in the upper region R1 or the lower region R2 is located at the inner peripheral position P1. The insertion hole 5 having the second opening 5c in the side region R3 is located at the outer circumferential position P2. Therefore, the strength of the tunnel lining portion T against positive bending moments can be increased in the upper region R1 and the lower region R2, and the strength of the tunnel lining portion T against negative bending moments can be increased in the side region R3.

For comparison, assume a segment assembly structure in which the central axes of all the second openings 5c and openings 6a are on the center line C in the thickness direction. In this case, it is necessary to provide sufficient strength to the tunnel lining portion T over its entire circumference so that it can withstand positive and negative bending moments. Therefore, this may be disadvantageous in terms of making the hexagonal segment thinner and lighter.

The present invention is not limited to the above-described embodiments, and appropriate changes and substitutions can be made without departing from the spirit of the present invention, and all of these are included in the present invention.
For example, although the hexagonal segment 1 shown in FIG. 1 has two side end surfaces 1a that are parallel to each other, the two side end surfaces 1a may not be parallel to each other. Although the hexagonal segment 1 shown in FIG. 2 is curved into a circular arc shape, the shape of the segment may be a flat plate shape or other shapes.

1 Hexagonal segment (segment)
1a Side end surface 1b Inclined end surface 1c Inclined end surface pair 1d Inner peripheral surface 5 Insertion hole 5c Second opening (opening)
11 Bolt (fastener)
R1 Upper region (region receiving positive bending moment)
R2 Lower region (region receiving positive bending moment)
R3 side area (area receiving negative bending moment)
T Tunnel lining part (cylindrical wall)

Claims (2)

A segment assembly structure in which a plurality of segments are combined to form a cylindrical wall body,
a plurality of hexagonal-shaped segments including a pair of opposing side end surfaces and a pair of V-shaped inclined end surfaces formed at both ends of the side end surfaces;
a fastener that connects the plurality of segments;
Equipped with
The pair of inclined end surfaces has two inclined end surfaces that are inclined to each other,
An insertion hole having an opening in the inclined end surface is formed in one of the circumferentially adjacent segments of the cylindrical wall body,
The fastener is inserted into the insertion hole and fixed to the other segment at a tip portion protruding from the opening,
The insertion hole having the opening in a region where the cylindrical wall body receives a positive bending moment due to an external force is compared to the insertion hole having the opening in a region where the cylindrical wall body receives a negative bending moment. A segment assembly structure located near the inner peripheral surface of the segment. The central axis of the insertion hole having the opening in a region where the cylindrical wall body receives a positive bending moment due to an external force is located closer to the inner peripheral surface than the center line in the thickness direction of the segment,
2. A central axis of the insertion hole having the opening in a region where the cylindrical wall receives a negative bending moment due to an external force is located closer to the outer circumferential surface than a center line in the thickness direction of the segment. assembly structure of segments.

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