JP2001227288A - Segment for tunnel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a segment for a tunnel reducible in the weight and cost of a segment body by forming the segment body out of synthetic resin, while suppressing electric power loss from a high-tension electric wire in the case of being used for protecting the high-tension electric wire. SOLUTION: This segment for the tunnel is constituted to form a peripheral wall of the tunnel T by arranging a large number of segment bodies 1 of circular arc shape in the circumferential and axial directions of the tunnel T to connect them. Each of a large number of segment bodies 1 is constituted to be spirally connectable along a center axis P of the tunnel T being twisted in such a manner that the centerline L of the segment body extending along the longitudinal direction is tilted relative to an orthogonal line Q orthogonal to the center axis P of the tunnel T from the top view. The segment bodies 1 are formed of synthetic resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tunnel segment formed by connecting a large number of arc-shaped segment bodies in a circumferential direction and an axial direction of a tunnel to form a circumferential wall of the tunnel. .

[0002]

2. Description of the Related Art Such a tunnel segment is used to protect a high-voltage electric wire or the like when a high-voltage electric wire or various cables are buried underground. The configuration shown is frequently used. In the prior art shown in this figure, each of a large number of arc-shaped segment bodies 1A is configured such that a center line LA along a longitudinal direction thereof is orthogonal to a center axis P of a tunnel T in plan view. The segment main body 1A is configured to be annularly connectable, and the annularly connected segment main body 1A
Are sequentially connected along the central axis P of the tunnel T to form a peripheral wall of the tunnel T. As described above, a special segment called a key segment KS is required to connect each segment body 1A in a ring shape from the inside, and the key segment KS
Has a tapered surface TF that tapers toward the outer periphery of the tunnel T, as shown in FIG.

[0003]

Therefore, in the prior art, when a large external force W acts due to earth pressure or the like, the external force W is applied to the key segment KS and the segment body 1A.
And acts as a shear force that tries to shear
Not only high rigidity is required for the bolt B1 connecting the both, but also high rigidity is required for the key segment KS and the segment body 1A through which the bolt B1 is inserted.
For this reason, in the related art, the key segment KS and the segment main body 1A are formed of cast iron or concrete, and are heavy in weight, making the construction work of the tunnel T difficult and more expensive. was there.

Further, when the key segment KS and the segment body 1A are made of cast iron and used for protecting high-voltage electric wires, the entire tunnel T is made of cast iron, so that the amount of eddy current generated is large. As a result, there is a problem that a large amount of power loss occurs.

The present invention focuses on such disadvantages of the prior art, and an object of the present invention is to enable the segment body to be formed of a synthetic resin, thereby reducing the weight and cost of the segment body. It is possible to provide a tunnel segment capable of suppressing power loss from a high-voltage wire when used for protection of a high-voltage wire.

[0006]

[Structure] According to a first feature of the present invention, as shown in FIGS. 1 and 4, a large number of arc-shaped segment bodies 1 are formed in a circumferential direction and an axial direction of a tunnel T. By connecting them side by side, the tunnel T
, The plurality of segment bodies 1 each have a center line L along a longitudinal direction orthogonal to a center axis P of the tunnel T in plan view. Twisted so as to be inclined with respect to the orthogonal line Q
And the segment body 1 is formed of a synthetic resin.

[0007] The characteristic structure of the invention according to claim 2 is that, as illustrated in FIG.
And a pair of long side wall portions 6 extending inward along the long side of the peripheral wall portion 5, and a pair of long side wall portions 6 extending inward along the short side of the peripheral wall portion 5. And a pair of short side wall portions 7 integrally provided.

As shown in FIGS. 2 and 3, the segment body 1 has a connecting segment 2, 3 made of synthetic resin at both ends in the longitudinal direction.
And a connecting space 9 for inserting the connecting segments 2 and 3 over the connecting space 9 of the segment bodies 1 adjacent to each other to spirally connect the adjacent segment bodies 1 to each other. In addition, the connection segment 2 is provided with a grout injection hole 12 for injecting grout outside the peripheral wall of the tunnel T.

Note that, as described above, reference numerals are provided for convenience of comparison with the drawings, but the present invention is not limited to the configuration of the accompanying drawings by the entry.

According to the feature of the first aspect of the present invention, each of the plurality of arc-shaped segment bodies has a center line along a longitudinal direction orthogonal to a center axis of the tunnel in plan view. It is twisted so as to be inclined with respect to the orthogonal line, and it is configured so that it can be connected spirally along the center axis of the tunnel, so that the tapered surface that tapers toward the outer peripheral side of the tunnel as in the past No special key segment is required. Therefore, even if a large force acts from the outside while the tunnel is formed, the external force mainly acts only as a compressive force for compressing each segment body in the longitudinal direction. With little force applied, the required rigidity of each segment body is significantly reduced as compared with the conventional one. Therefore, each segment main body can be formed of a synthetic resin, and by forming each segment main body with a synthetic resin, the weight and cost of the segment main body can be reduced. Further, when used for protection of a high-voltage electric wire, generation of eddy current can be reduced, and power loss from the high-voltage electric wire can be suppressed.

According to the characteristic feature of the second aspect of the present invention, the segment main body includes a peripheral wall portion forming a peripheral wall of the tunnel, and a pair of long side wall portions extending inward along a long side of the peripheral wall portion. Since it is configured integrally with a pair of short side wall portions which are located on the short side of the peripheral wall portion and extend inward, for example, the segment main body is formed of a solid block made of synthetic resin. In comparison with the above, the weight and cost can be further reduced, and the peripheral wall forming the peripheral wall of the tunnel is reinforced by the above-described long side wall and short side wall. In spite of weight reduction and cost reduction, each segment main body can have necessary and sufficient rigidity.

According to the characteristic structure of the third aspect of the present invention, the segment main body is provided with a connecting space for inserting a synthetic resin connecting segment at both ends in the longitudinal direction, and the connecting space of the adjacent segment main bodies. It is configured to insert the connecting segments over each other and to connect the adjacent segment main bodies in a spiral shape, so that the interposition of the connecting segments makes it possible to securely and firmly connect each segment main body. Since the grout injection hole for injecting grout into the outer peripheral wall of the tunnel is provided in the connecting segment, there is no need to provide the grout injection hole in the segment main body, and a decrease in the rigidity of the segment main body due to the drilling of the grout injection hole is suppressed. be able to.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a tunnel segment according to the present invention will be described with reference to the drawings. This tunnel segment is used, for example, to protect high-voltage electric wires and various cables when the high-voltage electric wires and various cables are buried in the ground. As shown in FIG. And two types of connecting segments 2 and 3 used to connect the respective segment bodies 1 to each other, and both ends of the tunnel T when forming the tunnel T by connecting the segment body 1 and the connecting segments 2 and 3 to each other. The segment body 1, the connecting segments 2, 3 and the end segment 4 are all formed of a synthetic resin, preferably a reinforcing material such as glass fiber or carbon fiber. It is composed of a molded article made of mixed high-rigidity reinforced synthetic resin.

Each of the segment bodies 1 has the same size and the same shape, and has a predetermined central angle in a front view as shown in FIGS. 2 and 5 so as to form the peripheral wall of the tunnel T. A peripheral wall portion 5 formed in an arc shape so as to have α, and a pair of long sides extending inward along a long side of the peripheral wall portion 5 and formed so as to have a predetermined central angle α. A side wall part 6 and a pair of short side wall parts 7 which are located on the short side of the peripheral wall part 5 and extend inward are integrally provided. Is provided, the reinforcing wall portion 8 is provided,
The pair of long side walls 6 are integrally connected. As shown in FIG. 4, each segment body 1 has a predetermined inclination angle β such that a center line L along a longitudinal direction thereof has a predetermined inclination angle β with respect to an orthogonal line Q orthogonal to the center axis P of the tunnel T in plan view. It is configured to be spirally connectable along the central axis P of the tunnel with the connection segments 2 and 3 being interposed between them.

The short side wall portion 7 of each segment body 1 is located slightly inside from the short side edge of the peripheral wall portion 5, that is, a part of the peripheral wall portion 5 from the short side wall portion 7. The protruding wall 5a of the peripheral wall portion 5 and the long side wall portion are provided so as to protrude and a part of each long side wall portion 6 to protrude in a triangular shape. 6 projecting walls 6
a is formed so that the connection space 9 having a triangular cross section is formed. And in each short side wall part 7,
A plurality of connection holes 10 for inserting the bolt B1 are formed, and a plurality of connection holes 11 for inserting the bolt B2 are also formed in each long side wall portion 6.

As shown in FIG. 3A, the connecting segments 2 and 3 are provided with an injection-purpose connecting segment 2 having a grout injection hole 12, and as shown in FIG.
There are two types, a connection segment 3 without a grout injection hole 12 and both connection segments 2 and 3
Except for the presence or absence of 2, they have the same size and the same shape. In other words, both connecting segments 2 and 3
As shown in FIG. 6, the outer peripheral surfaces of the connection segments 2 and 3 are formed so as to be insertable into the connection space 9 formed at both ends of the segment main body 1 and inserted into the connection space 9. The outer peripheral surface of the peripheral wall portion 5 of the segment main body 1 is continuously connected to the inner peripheral surface of the long side wall portion 6 of the segment main body 1. And a plurality of through holes 13 for inserting the bolts B1.

As shown in FIG. 1, the end segment 4 is formed in an annular shape which is entirely spirally wound, and its end surface 4a is formed on a surface orthogonal to the central axis P of the tunnel T. At the end of the spiral, a connection space 14 into which the connection segments 2 and 3 can be inserted is provided, and a plurality of connection spaces 14 for inserting the bolt B1 are provided in the connection space 14 portion. The connection hole 15 is provided, and a plurality of connection holes 16 for inserting the bolt B2 are provided in the side wall portion 17 of the end segment 4.

Next, a procedure for forming a tunnel T using the segment body 1, the connecting segments 2, 3 and the end segments 4 will be described. First,
The end segment 4 is disposed at the end of the tunnel T to be formed, and one of the connection segments 2 and 3 is inserted into the connection space 14 of the end segment 4. In other words, after the tunnel T is formed, if grout needs to be injected between the outside of the connection space 14 in the end segment 4 and the ground, the injection / connection joint segment 2 having the grout injection hole 12 is inserted. If you do not need grouting,
Insert connecting segment 3.

The segment body 1 is positioned along the spiral of the end segment 4 and the connection segments 2 and 3 inserted into the connection space 14 of the end segment 4 are inserted into the connection space 9 of the segment body 1. The bolt B1 is inserted through the connecting hole 15 of the end segment 4, the through hole 13 of the connecting segment 2, 3 and the connecting hole 10 of the segment body 1 and fastened by the nut N1. The bolt B2 is inserted through the connection hole 16 of the above and the connection hole 11 of the segment main body 1, and is tightened and fixed by the nut N2.

Thereafter, one of the connecting segments 2 and 3 is inserted into the connecting space 9 of the segment body 1 fixed to the end segment 4, and the connecting segments 2 and 3 are inserted.
3 into the connection space 9 of another segment body 1,
The bolts B1 and B2 and the nuts N1 and N2 are used for fixing, and the above procedure is repeated to arrange a number of the segment bodies 1 and the connecting segments 2 and 3 in the circumferential direction and the axial direction of the tunnel T until the desired length is reached. The spiral segments are sequentially connected, and finally, the end segments 4 are fixed to form a cylindrical tunnel T. Then, grout is injected from the grout injection hole 12 of the injection / connection segment 2 arranged at a necessary place, and the construction of the tunnel T is completed.

[Other Embodiments] (1) In the above embodiment, the segment main body 1 is connected to the peripheral wall 5.
Although the example in which the wall portions 6 and 7 on the long side and the short side are configured has been described, the segment body 1 can be formed of a synthetic resin by connecting the segment bodies 1 in a spiral shape. And the segment body 1
Various changes can be made to the specific configuration of. When the segment body 1 is formed, the above-described center angle α and the inclination angle β are appropriately set according to the diameter of the tunnel T and the like.

(2) In the above embodiment, an example was shown in which the connecting segments 2 and 3 were connected with each other when connecting the segment bodies 1 to each other.
It is also possible to adopt a configuration in which the segment bodies 1 are directly connected to each other without using the segment bodies 3. When the connecting segments 2 and 3 are used, the injection-use connecting segment 2 having all the grout injection holes 12 may be used as the connecting segments, or the connecting segment 3 without the grout injection holes 12 may be used. Can be used. In that case, a grout injection hole is provided in the segment body 1 as necessary.

(3) In the above embodiment, an example is shown in which all the segment main bodies 1 are configured to have the same size and the same shape. For example, two or more types of segments having different lengths in the longitudinal direction. Helical connection using the main body 1 or two or more types of structurally different segment main bodies 1
Various changes can be made, for example, by using a highly rigid segment body 1 at a location where a large external force acts.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a construction state of a tunnel.

FIG. 2 is a perspective view showing a segment main body.

FIG. 3 is a perspective view showing a connecting segment.

FIG. 4 is a plan view showing a connected state of the segment main bodies.

FIG. 5 is a front view of the tunnel.

FIG. 6 is a sectional view of a main part showing a connected state of the segment main bodies.

FIG. 7 is a perspective view showing a conventional segment main body.

FIG. 8 is a cross-sectional view of a main part showing a connected state of a conventional segment main body.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Segment main body 2, 3 Connecting segment 5 Peripheral wall part 6 Long side wall part 7 Short side wall part 9 Connecting space 12 Grout injection hole L Center line of segment body P Center axis of tunnel Q Line perpendicular to center axis of tunnel T Tunnel

Claims (3)

[Claims] 1. By connecting a large number of arc-shaped segment bodies in a circumferential direction and an axial direction of a tunnel,
A tunnel segment configured to form a peripheral wall of the tunnel, wherein each of the plurality of segment bodies is orthogonal to a center line along a longitudinal direction thereof, which is orthogonal to a center axis of the tunnel in plan view. Twisted so as to be inclined with respect to the line,
A tunnel segment configured to be spirally connectable along a central axis of the tunnel, and the segment body is formed of a synthetic resin. 2. The segment body has a peripheral wall forming the peripheral wall of the tunnel, a pair of long side walls extending inward along a long side of the peripheral wall, and a short side of the peripheral wall. 2. The tunnel segment according to claim 1, further comprising: a pair of short side wall portions extending inwardly at a position. 3. The segment main body includes a connecting space for inserting a synthetic resin connecting segment at both ends in a longitudinal direction thereof, and the connecting segment is inserted over the connecting space of the adjacent segment main bodies. 3. The tunnel according to claim 1, wherein the adjacent segments are spirally connected to each other, and the connection segment is provided with a grout injection hole for injecting grout outside a peripheral wall of the tunnel. 4. segment.