JP3276579B2 - How to assemble a segment ring - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a segment used for tunnel lining in a shield tunnel excavation method, and more particularly to a trapezoidal segment having a flat trapezoidal shape (a flat trapezoidal segment sometimes referred to as a T-shaped segment). (Including a convex segment of a convex shape).

Hitherto, trapezoidal segments having a trapezoidal or convex planar shape have been used as tunnel lining segments. This trapezoidal segment is generally made of reinforced concrete, and since the segment joint surface can transmit the bending moment not only in the direction perpendicular to the ring joint surface but also with the shear force acting on the joint surface, while suppressing the decrease in the rigidity of the segment joint, It has the advantage that the proof stress can be improved.

[0003] Incidentally, this type of trapezoidal segment is divided into equal parts so that only one type can be used for each because of a demand for cost reduction in manufacturing a manufacturing formwork and a reinforcing steel cage to be embedded (all segments having the same shape). Eggplant.) Is common.

In this type of trapezoidal segment, the last segment to be assembled is inserted between the previously assembled trapezoidal segment in the wellhead direction from the face side, that is, in the tunnel axial direction. I like to assemble.

However, this equal trapezoidal trapezoidal segment has a large segment to be inserted and assembled in the tunnel axis direction, and the jack stroke of the shield machine and the tunnel axis stroke of the erector (hereinafter, including both strokes, However, there is a problem that the shield excavator becomes longer.

That is, in order to assemble such a conventional trapezoidal segment into a segment ring in the tail portion of a shield machine, generally, a propulsion jack has a jack stroke having a segment width R and a certain margin α (R).
+ Α). As shown in FIG. 6, the last trapezoidal segment to be incorporated is carried into the face side (downward in the figure) from the previously assembled trapezoidal segments S1, S1, S1,. (Indicated by arrow P1 in the figure) and inserted between trapezoidal segments S1 and S1 assembled in advance.

Therefore, the distance from the previously completed segment ring (the preceding segment ring is not shown in FIG. 6) to the face side end face of the trapezoidal segment S1 installed at the insertion position for the last assembly is " As shown in FIG. 6, (R + α), and this distance is the necessary stroke of the propulsion jack.

Accordingly, in the above-mentioned conventional method, the distance of the above-mentioned (α) is large (actually, this α is set from about R to about 0.8). R + α) becomes too long, the length of the seal excavator becomes too long, and there arises a problem that it is impossible to excavate a sharply curved tunnel. Therefore, various attempts have been made to shorten the jack stroke.

One of the above-mentioned attempts is to reduce the inclination angle の 長 1 (see FIG. 7) of the trapezoidal hypotenuse by setting a large difference between the lengths of the ring joint surfaces of the trapezoidal segments facing each other. is there. That is, as shown in FIG. 7, when the inclination angle ∠Θ1 is small, the narrow side of the trapezoidal segment S1 moves in the centrifugal direction of the tunnel instead of being inserted in the tunnel axial direction (see FIG. 7). Then, the trapezoidal segment S1a is placed at the position shown in the figure from the near side in the figure.)
Thus, the previously assembled trapezoidal segments S1, S1
During this time, a part of the reduced-width ring joint surface side can enter by the distance X1. Since the distance X1 increases as the inclination angle ∠Θ1 decreases, the jack stroke can be shortened by that dimension.

However, reducing the inclination angle 傾斜 1 results in providing an acute angle portion in the trapezoidal segments S1 and S1a. In the case of a reinforced concrete segment, the acute angle portion is easily chipped, so that the inclination angle ∠Θ1 is unlimited. Cannot be reduced, and this proposal is said to have limitations.

Next, a convex segment has been proposed to reduce the jack stroke by avoiding the occurrence of an acute angle portion. In this convex segment, the width is reduced stepwise from the widened ring joint surface 11 toward the reduced ring joint surface 12 by the stepped slopes 13, 13. Since it is performed extremely at the approximate center of the segment width R, as shown in FIG. 8, the jack stroke can be reduced without providing an acute angle portion in the segment (the α can be reduced to about 1/2 ・ R). .)It is known.

However, in the above-mentioned conventional method, the jack stroke is still long, and it is required to further reduce the jack stroke and the total length of the shield excavator in a sharply curved tunnel excavation or the like.

Further, as shown in FIG. 9, joints J, J, J,.
Is located on the crown or the spring line SL, which causes a large positive bending or a negative bending, which is disadvantageous in terms of structure.

[0014]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a trapezoidal lining segment that requires a short jack stroke, and furthermore, the type of the trapezoidal segment is limited to two types, large and small. An object of the present invention is to provide a lining segment that limits the manufacturing cost to a high level and minimizes the reduction in work efficiency.

It is a further object of the present invention to provide a lining segment in which the joint positions of six equally divided segments are not arranged on a crown or a spring line.

[0016]

According to the present invention, there is provided a segment ring comprising a large trapezoidal segment having a long arc length and a small trapezoidal segment having a short arc length . By assembly method
Therefore, the small trapezoidal segment S2 was installed in advance.
When transporting to an installation location between large trapezoidal segments S1
The phosphorus on the narrow side of the trapezoid of the small trapezoidal segment S2
Large trapezoidal segment with the joint surface side installed earlier
In the direction of tunnel centrifugal with part entering during S1
It takes technical means to move .

Therefore, in the present invention, the lining segment has a function of shortening the jack stroke by inserting the small trapezoidal segment S2 having a short arc length in the axial direction and incorporating it.

That is, the small trapezoidal segment S2 having a short arc length has a small circumferential difference δ1, which is the difference between the outer arc length and the inner arc length, smaller than the circumferential difference δ2 of the large trapezoidal segment S1 having a long arc length. When this small trapezoidal segment S2 is transported to the installation location by an erector, as shown in FIG.
The trapezoidal narrow side ring joint surface side can be moved in the centrifugal direction of the tunnel in a state where a part thereof enters between the large trapezoidal segments S1 and S1 previously installed. The distance that can enter between the segments S1 and S1 is greater than the distance X1 “FIG. 6”, and the jack stroke can be set shorter accordingly.

It should be noted that the small trapezoidal segment S2 exhibits an operation in which an acute angle portion does not occur because the above-mentioned inclination angle ∠Θ1 does not change.

Further, that make up a combination of an even split segment ring S six or more divisions, as long large trapezoidal segments S1 and an arc length short small trapezoid segment S2 of arc length
It may be taken the technical means.

In this case, although the lining segment is an even-numbered segment ring S having six or more divisions, the segments J are unequal, and as shown in FIGS.
J, load bending moment on the J position crown or spring line · · · SL is that Teisu action deviates than the maximum value portion.

[0022]

Next, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the figure, S1 is a large trapezoidal segment having a long arc length, and S2 is a small trapezoidal segment having a short arc length.

The large trapezoidal segment S1 and the small trapezoidal segment S2 are formed such that each of the segments has a trapezoidal planar shape when a segment ring having a predetermined width to be assembled is divided. (Referred to as a widened ring joint surface 11) and the other opposite short ring joint surface (referred to as a narrowed ring joint surface 12), which is narrower than the widened ring joint surface 11. 11 and the reduced width ring joint surface 12 are connected by a pair of inclined segment joint surfaces 13a and 13b.

The large trapezoidal segment S1 and the small trapezoidal segment S2 include a convex segment as one embodiment, and the convex segment has the segment joint surfaces 13a and 13b shown in FIG. 8 ".

In the present application, the term "arc length" means the circumferential dimension of the segment. The circumferential dimension of the widened ring joint surface 11 is short, and the "arc length" of the narrowed ring joint surface 12 is correspondingly reduced. Those having a short circumferential dimension are referred to as having a short arc length.

The present invention provides a large trapezoidal segment S1 having a long arc length and a small trapezoidal segment S2 having a short arc length.
To form the segment ring S. The combination of the large trapezoidal segment S1 and the small trapezoidal segment S2 is limited to two types, and as long as the segment ring S (usually circular) can be assembled finally, the large trapezoidal segment S1 and the small trapezoidal segment are combined. The segment S2 and the segment S2 may be used in appropriate numbers.

However, if the large trapezoidal segment S1 and the small trapezoidal segment S2 are used in combination in an excessively complicated manner, the operation management becomes complicated and the workability is inferior, so that one small trapezoidal segment S1 is used. The remaining trapezoidal segments S2, S2, S2,... Are most practical in terms of workability.

When only one small trapezoidal segment S2 is used, the large trapezoidal segments S1, S1, S1... Are sequentially stacked from the lower one, and finally the small trapezoidal segment S2 is Incorporation at or near the top of the segment ring to complete the segment ring S.

That is, the segment ring S
When assembling the large trapezoidal segments S1, S1, S1
.. Are sequentially stacked, the large trapezoidal segment S1
Segment width R and a small margin α (50 to 100
mm is sufficient).
If there is some extra space in the circumferential direction, it is possible to assemble sequentially. The last small trapezoidal segment S2 has large trapezoidal segments S1 and S1 already assembled on both sides to be assembled. Therefore, in order to fit the small trapezoidal segment S2, it must be inserted in the tunnel axial direction. In the segment S2, the circumferential length difference δ1, which is the difference between the outer arc length and the inner arc length, is small, and the jack stroke can be set short as described above.

Next, a plurality of large trapezoidal segments S1, S1, S1... Having a long arc length and small trapezoidal segments S2 having the same number of small trapezoidal segments S2, S1, S1, S1. If the segment ring S is formed by alternately positioning S2, S2,..., The number of manufacturing molds is small, and it is economical.

That is, as shown in FIG. 1 and FIG. 2, every other large trapezoidal segment S1 and small trapezoidal segment S2 are located. It is necessary to alternately arrange the widened ring joint surface side and the narrowed ring joint surface side. In this case, the large trapezoidal segment S1 and the small trapezoidal segment S2 may be used. Arranging S1 and small trapezoidal segments S2 alternately does not impair workability. In addition, "FIG. 1"
2 and “FIG. 2”, the upper side of the figure is the wellhead side, and the lower side of the figure is the face side.

Further, even split segment ring S six or more divisions, as long large trapezoidal segments S1 of arc length, so as to constitute at small size and small trapezoidal segment S2 of arc length
Is also good.

If the even-numbered divided segments of 6 or more are equally divided, the positions of the joints J, J, J... Are arranged on the crown or the spring line SL. However, as shown in FIGS. 3 and 4, the joint position comes off on the crown or the spring line, resulting in a structural disadvantage. Is one that can escape.

In the case of an even-numbered segment having six or more segments, one small trapezoidal segment S2 having a short arc length may be used, and all other segments may be made into a large trapezoidal segment S1. May be alternately positioned, or either of them may be used.

[0035]

As described above, the present invention can provide a lining segment capable of shortening the jack stroke and the total length of the shield machine even when a trapezoidal segment is used.

In the present invention, since the jack stroke is shortened by the small trapezoidal segment S2 having a short arc length, it is possible to provide a lining segment which does not generate an acute angle portion and is less likely to be damaged. Things.

Since the present invention uses two types of large and small trapezoidal segments, it is sufficient to prepare only two types of formwork and a reinforcing steel cage to be embedded, and the rise in cost can be minimized. A lining segment can be provided.

Since only two types of large and small trapezoidal segments are used as described above, it is possible to provide a lining segment that is easy to manage and has good workability.

[0039]

[Brief description of the drawings]

FIG. 1 is a developed plan view of a segment ring using a lining segment of the present invention.

FIG. 2 is an exploded plan view of a segment ring in another embodiment.

FIG. 3 is a schematic tunnel sectional view of a segment ring using the lining segment of the present invention.

FIG. 4 is a schematic cross-sectional view of a segment ring using a lining segment in another embodiment of the present invention.

FIG. 5 is a plan view showing a state where the lining segment of the present invention is incorporated last.

FIG. 6 is a plan view of a conventional example in a state where a trapezoidal segment is incorporated last.

FIG. 7 is a plan view of another conventional example with a trapezoidal segment incorporated last.

FIG. 8 is a plan view of still another conventional example with a trapezoidal segment incorporated last.

FIG. 9 is a schematic sectional view of a tunnel using the equally divided segments of the conventional example 6.

[Explanation of symbols]

 S segment ring S1 Large trapezoidal segment S2 Small trapezoidal segment

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-5-25991 (JP, A) JP-A-8-13991 (JP, A) JP-A-10-82291 (JP, A) 247898 (JP, A) JP-A-8-93393 (JP, A) Japanese Utility Model Application Sho 62-60696 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) E21D 11/04 E21D 11 / 08

Claims (1)

(57) [Claims] A large trapezoidal segment having a long arc length (S1)
And a small trapezoidal segment (S2) with a short arc length, which constitutes a segment ring (S).
A method for assembling a ring, comprising a small trapezoidal segment (S2),
When transporting to an installation location between trapezoidal segments (S1)
To the phosphorus trapezoidal contraction width side of the small trapezoid segments (S2)
Large trapezoidal segment with the joint surface side installed earlier
Centrifugal direction of tunnel with part entering during (S1)
Set of segment rings characterized by moving in the direction
Standing method.