JP2837289B2 - Segment assembly method in shield method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for assembling segments in a shield construction method in which a ring body is constructed by sequentially connecting arc-shaped segments at joint end faces along the axial direction of a drilled hole.

[0002]

2. Description of the Related Art As a conventional method of assembling a segment in a shield method, there is known a method as shown in FIGS.

In FIG. 5, a segment (hereinafter referred to as a key segment) 1 to be set last has a substantially trapezoidal cross section along a circumferential direction of an excavation hole. When segment 2 is joined from the bottom of the drill hole,
A cavity corresponding to the outer shape of the key segment 1 is formed above the excavation hole. Key segment 1 is inserted into this space from the inside of the drill hole, and segment 2 is inserted.
And are interconnected.

In FIG. 6, the key segment 3 is shaped such that the cross-sectional area gradually decreases along the axial direction of the excavation hole. Similarly to the above-described example, when the segments 4 are sequentially joined from the lower part of the excavation hole, a space corresponding to the outer shape of the key segment 3 is formed at the upper part of the excavation hole. The key segment 3 is inserted into the space along the axial direction of the excavation hole, and the key segment 3 and the segment 4 are connected.

[0005]

However, according to the conventional method of assembling the segments in the shield method shown in FIG. 5, when a load is applied to drop the key segment 1 into the inside of the excavation hole, the key segment 1 itself is removed. It may shift at the joint surface and move toward the inside of the excavation hole. That is, since the key segment 1 has a trapezoidal shape in which the skirt expands toward the inside of the borehole, there is a drawback that a so-called wedge effect cannot be obtained in the inside of the borehole.

[0006] In the segment assembling method in the conventional shield method shown in FIG. 6, the key segment 3 is shaped such that the cross-sectional area gradually decreases along the axial direction of the excavation hole. When the key segment 3 is slightly moved in the axial direction of the digging hole due to the load acting on the digging hole in the axial direction, a gap is generated between the key segment 3 and the joining end face of the segment 4 adjacent to the key segment 3. As a result,
There is a drawback that the frictional force does not act on the joint end surface of the key segment 3 and the joint end surface of the segment 4, and the assembling strength is reduced with respect to the load along the axial direction of the excavation hole.

The present invention has been made in view of the above circumstances, and relates to a method of assembling a segment in a shield method in which a key segment can be firmly connected to a joint end face of an adjacent segment and has good workability. .

[0008]

A method for assembling a segment in a shield method according to the present invention is a method for assembling a ring body by sequentially connecting arc-shaped segments at joint end faces along the axial direction of a drilled hole. In the segment assembling method, the radius of the arc of at least a part of the segment adjacent to the key segment to be connected last is reduced.
Te, while such a gap is formed between the inner and the assembled position of the key segment of the wellbore, the key
-The width of the segment from the inner circumference to the outer
The key segment is formed in a tapered shape that gradually spreads.
Other segments and the key segment
After setting the adjacent segment, place it in the gap.
The key segment that has been placed
The ring body is assembled by fitting
It is characterized by standing up .

[0009]

In the segment assembling method in the shield method according to the present invention, the ring is constructed by assembling the segments on the inner surface of the excavation hole and finally assembling the key segments.

[0010] At this time, the radius of at least part of the arc of the segment adjacent to the key segment is smaller than that of the other segment, and a gap is formed between the inner surface of the excavation hole and the key segment mounting position, The key segment is inserted into this gap from the axial direction of the excavation hole.

Thereafter, when the support of the key segment is released, the key segment falls downward by the action of gravity, and
The joining end face of the key segment is wedge-bonded to the joining end face of the adjacent segment. As a result, the rigidity of the key segment and the ring body formed by the segments is improved.

[0012]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a front view of an excavation hole as viewed from its axial direction, FIG. 2 is a perspective view showing the shape of a key segment, FIG. 3 is a perspective view of a lining body constructed from the segment as viewed from the outside, and FIG. It is an enlarged front view which shows the mounting structure of.

As shown in FIG. 1, in a ring-shaped tail plate 10 of a shield machine, concrete segments 11, 12, 13, and a key segment 14 are respectively arranged along the axial direction of the excavation hole. The ring body A is constructed by joining at the joining end faces.

The segment 11 has an inner surface having an arc radius of R1.
And the outer surface has a circular arc shape with an arc radius of R2, and when assembled to the excavation hole, the joint end face along the circumferential direction of the excavation hole has a joint fitting 1 on a line of a radius R3 concentric with the inner surface arc.
6 are buried. The segment 12 is an arc half of the inner surface
It is in the shape of an arc plate with a diameter of R4 and an outer radius of R5, and a joint fitting 1 on a line of a radius R6 concentric with the inner surface of the arc.
6 are buried.

Here, the arc radii R4,
R5 is formed to be larger than the arc radii R1 and R2 of the segment 11. Segment 13 also has a similarly arcuate plate shape, the end adjacent to the key segment 14, the arc radius R of the arc radius R4, R5 the same portion or arc radius segments 11 of the circular arc radius of the segment 12
A portion 13a larger than 1, R2 is formed. The segment 13 also has a joint fitting 16 along the circumferential direction.
Is buried. However, the above segments 12, 13
The position of the bolt hole of the joint fitting 16 of the segment 1
The same arc radius as the bolt hole of the joint fitting 16 provided in 1
It is a position passing through.

The segments 12 and 13 include:
In part of this, the radius of the arc is
A portion smaller than the radius is formed. like this
In addition, these segments 12 and 13 partially include an arc.
Is smaller than the radius of the arc of the other segment 11
And the key segment 14
On the mating side, change the arc radii of segments 12 and 13 to other
As shown in FIG. 4, the distance between the outer peripheral surface of the segment 11 and the tail plate 10 is smaller than the distance between the outer peripheral surface of the segment 12 and the tail plate 10 as shown in FIG. A large gap 15 is also formed. Note that the two-dot chain line in FIGS. 1 and 4 is obtained by extending the arc of the segment 11.

Further, the two joining end faces 14a, 14b along the axial direction of the excavation hole of the key segment 14 are tapered such that the distance between the joining end faces 14a, 14b gradually increases from the inside of the excavation hole to the inner wall. Surface. In other words, this key segment 14 is
Formed in a tapered shape whose width gradually increases toward the circumference
Have been.

As shown in FIG. 3, the mounting positions of the key segments 14 are staggered along the axial direction of the excavation hole.

[0019]

Referring to FIG. 4, the order of assembling the key segments 14 in this embodiment will be described. That is, the key segment 14 is formed by the gap 1 outside the segments 12 and 13.
In 5, the outer surface is floated so as to be in contact with the tail plate 10 and inserted in the axial direction of the excavation hole. Thereafter, the key segment 14 is connected to the joining end face 12
a, 13a. As a result, key segment 1
The four tapered joint end surfaces 14a, 14b are wedge-bonded to the joint end surfaces 12a, 13a of the adjacent segments 12, 13. Thereafter, they are connected to each other by a joint fitting (not shown).

In the present embodiment, the radius of the arc is set to a part of the segments 12 and 13 adjacent to the key segment
To form a portion smaller than the radius of the arc of the segment 11.
At the same time, a portion having a large arc radius is formed, a gap 15 is formed between the inner surface of the excavation hole and the segments 12 and 13, and the key segment 14 is inserted and dropped into the gap 15. Insertion and assembling of the key segment 14 are facilitated, and workability of assembling the key segment 14 can be improved.

Further, the joining end face 1 of the key segment 14
4a, 14b are formed in a tapered shape, and the segments 12, 1
Since the key segments 14 are dropped between the joint end surfaces 12a and 13a of the third and the wedge-joined joint end surfaces, the rigidity of the ring constituted by the segments 11, 12, 13 and the key segment 14 is increased.

[0023]

As described above, according to the method of assembling the segments in the shield method according to the present invention, at least the segments adjacent to the key segment to be finally connected are required.
Also partially make the radius of the arc greater than the radius of the arc of the other segment
A reduced portion is formed so that a gap is formed between the inside of the excavation hole and the assembly position of the segment, and the key segment is moved from the inner peripheral side to the outer peripheral side.
To form a tapered shape whose width gradually increases,
Segments adjacent to other segments and key segments
After setting the key, the key seg
Since the segments are fitted between adjacent segments from the outer peripheral side , the workability of assembling the segments is greatly improved, and a highly rigid ring body can be constructed on the inner surface of the excavation hole.

[Brief description of the drawings]

FIG. 1 is a view showing an assembling structure of a key segment according to one embodiment of the present invention, and is a front view of an excavation hole as viewed from an axial direction thereof.

FIG. 2 is a perspective view showing a key segment assembling structure according to one embodiment of the present invention, showing a shape of the key segment;

FIG. 3 is a perspective view showing an assembling structure of a key segment according to one embodiment of the present invention, and is a perspective view of a lining body constructed by the segments as viewed from an outer surface.

FIG. 4 is an enlarged front view showing a key segment mounting structure according to one embodiment of the present invention, showing a key segment mounting structure;

FIG. 5 is a perspective view showing a conventional key segment mounting structure.

FIG. 6 is a perspective view showing a conventional key segment mounting structure.

[Explanation of symbols]

 11 segment 12 segment 12a joining end face 13 segment 13a joining end face 14 key segment 14a, 14b ... joining end face 15 gap A ring body

Claims (1)

(57) [Claims] 1. A method for assembling a segment in a shield construction method in which arc-shaped segments are sequentially connected at a joint end face along an axial direction of a drilled hole to construct a ring body, wherein a segment adjacent to a key segment to be finally connected is provided. of
By reducing at least a portion of the radius of the arc, while in a gap is formed between the inner and the assembled position of the key segment of the wellbore, the key segment
, The width gradually increases from the inner circumference to the outer circumference
It is formed in a tapered shape, and other segments except the key segment and the key are formed.
-After setting the segment adjacent to the segment,
The key segment placed in the gap is
By fitting from the outer periphery between the segments to be
A method for assembling a segment in a shield method, comprising assembling a ring body .