JPH11294091A - Lining structure of variable cross-sectional shield - Google Patents

Abstract

PROBLEM TO BE SOLVED: To secure strength of the straight line part, and to improve strength performance of a shield by using segments having the straight line part having the length according to an expanded width quantity as segments used in the part containing the straight line part of an expanded width part cross section. SOLUTION: RC segments 11A, 11B, 11K are used in the general part of a circular cross section, and segments 11A. 11K and steel segments 11M, 11N are used in the taper part or the expanded width part. For example, the horizontal part 11y is provided between the two circular arc parts 11x, the segment 11M is adjacent to the front side of the segment 11K in the clockwise direction in a cross section, and the segment 11N is adjacent to the rear side of the segment 11K. The length of the horizontal part 11y of the segments 11M, 11N is set to the length according to an expanded width quantity on the left/right of a tunnel, and the segments 11M, 11N are used in a place having a large expanded width quantity. Therefore, rigidity of the segments assembled in nonpresence of the horizontal part crossing joining part increases in a tunnel cross section having the horizontal part on the upper/lower sides to secure sufficient strength in the bending moment.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a variable-width shield lining structure in which a part of a tunnel in a radial direction is widened so that a cross-sectional shape of a widened portion has a straight portion.

[0002]

2. Description of the Related Art Conventionally, when a tunnel is excavated by a shield excavator, the cross section of the tunnel is generally formed in a circular shape. When the middle section of the tunnel is enlarged by an enlarged shield method or the like, FIG.
As shown in the figure, after assembling the circumferential segment 52 at the portion where the enlarged shield of the primary segment 51 having the circular cross section is to be started, the enlarged shield 53 is provided inside the circumferential segment 52.
Then, as shown in FIG. 13B, the enlarged shield 53 is dug in the tunnel direction to form an enlarged shield having a diameter larger than the outer diameter of the primary segment 51.
By the way, when expanding the middle section of the tunnel,
The cross section is not always expanded uniformly, but rather, as shown in FIG. 14 (a), when the width is expanded only in the left and right directions of the circular cross section, the excavation amount is smaller and more practical. . Therefore, using a shield excavator that moves the shield body in the left and right directions of the excavation direction of the shield excavator, and expands only the left and right directions of the circular cross section in the widening part of the tunnel. A method of excavating a tunnel has been proposed. When lining a variable cross-section shield such that the cross section of the tunnel changes in the excavation direction of the shield, for example, a normal circular arc arranged in a side circle portion as shown in FIG. The upper segments 11A, 11B and 11K and the flat plate segment 11H arranged on the widened horizontal portion are used. The segment 11K is a K segment.

[0003]

However, FIG.
A shield having a horizontally long cross-sectional shape as shown in FIG. 7A exerts a larger bending moment than a shield having a circular cross-section. In particular, since the bending moment applied to the horizontal portion is large, for example, in a rectangular shield such as a rectangular shield, measures such as enlarging the cross section of the segment to be used are taken. In addition, when a segment having a joint that crosses the horizontal portion is used in the horizontal portion of the widened portion, there is a problem that a gap occurs between the segments and water leaks from the joint. there were.

The present invention has been made in view of the conventional problems, and in a variable cross-section shield in which the cross-sectional shape of the widened portion has a straight portion, the strength of the straight portion is secured and the strength performance of the shield is improved. It is an object of the present invention to provide a lining structure of a variable cross-section shield that can be used.

[0005]

According to the first aspect of the present invention, the lining structure of the variable cross section shield has a length corresponding to the widening amount as a segment used for a portion including a straight portion of the cross section of the widening portion. It is characterized in that a segment having a straight portion is used.

According to a second aspect of the present invention, in the lining structure for a variable cross-section shield, the segments are constituted by two arc portions and a horizontal portion formed between the two arc portions. And

[0007]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing a configuration of a shield machine 20 according to an embodiment of the present invention.
1A is an overall sectional view, and FIG. 1B is a front view. In the figure, 1 is a main cutter mounted on the front surface of a shield machine 20 for excavating a face, and 2 is a pair of main cutters mounted on the main cutter 1 and capable of expanding and contracting in the radial direction of the main cutter 1 (radial direction of the shield). Equipment of 3L, 3
R is a left and right widening cylinder having an arc-shaped cross section that moves left and right respectively, 4 is a disk-shaped partition wall arranged at the rear of the main cutter 1, 5A and 5B are a plurality of sub-cutters 5k on the front surface. And a flat horizontal frame extending parallel to the axial direction of the shield machine 20. Reference numeral 5A denotes an upper horizontal frame constituting an upper trunk, and 5B denotes a lower horizontal frame constituting a lower trunk. The horizontal frames 5A, 5B
Constitutes the shield body 3 together with the left and right widening cylinders 3L and 3R. Further, 6 is provided inside the middle body of the shield, and the horizontal frame 5 is provided together with the partition 4.
A column for supporting A and 5B, 7 is the horizontal frame 5A and 5
B, attached to the inside of the shield of B
A slide jack for moving L and 3R to the left and right respectively, 8 is a shaft portion of the main cutter 1, 9 is a driving device of the main cutter 1, and 10 is a shield propulsion for pushing the segment 11 to advance the shield excavator. A jack, 12 is an erector for assembling the segment 11 into a ring shape, and 13 is the segment 11 and the shield machine 2
This is a tail seal for stopping water installed between the tail seal. In the upper and lower horizontal frames 5A and 5B, a driving device 5m for the sub-cutter 5k is provided at the rear of the sub-cutter 5k.
Is stored. Further, in order to simplify the drawing, a mud pipe 14 for sending high-pressure muddy water in front of the partition wall 4 and a drainage for sending earth and sand excavated by the main cutter 1 and the above muddy water to the rear of the shield. The mud pipe 15 is indicated by a two-dot chain line.

FIG. 2A is a sectional view taken along the line AA in FIG. 1A. Three sub-cutters 5k are provided at both ends of each of the horizontal frames 5A and 5B. Among the sub-cutters, the center sub-cutter is located on the front side of the other sub-cutters (see FIG. 1B). Further, a mud pipe 14 is provided at the center of the front surface of the upper horizontal frame 5A.
The agitator 16 for stirring the excavated earth and sand and the muddy water from the mud port 14a and the mud port 15 of the mud pipe 15 are provided in the center of the front surface of the lower horizontal frame 5B.
a. One of the outlets 15a in the figure is a spare outlet. Also, the left and right widening cylinders 3L,
Moving portions 3p and 3q are provided on a portion corresponding to the back side of the partition 4 of the 3R so as to be in close contact with the partition 4 with a waterproof seal (not shown) interposed therebetween. FIG.
In the sectional view taken along the line BB of FIG.
It is composed of two parallel bar-like members which are vertically built between the horizontal frames 5A and 5B between 5B. The drive device 9 for the main cutter 1 is provided concentrically with the shield body 3 at left and right three each.
Numeral 0 is provided concentrically inside the shield body 3. Specifically, the horizontal frame 5 which is an upper trunk and a lower trunk
A, the shield propulsion jack arranged inside 5B,
The other shield propulsion jack, which is arranged at the rear of the driving device 5m of the sub cutter 5k, moves the left and right widening cylinders 3
It is arranged inside L, 3R. In FIG. 1B, the erector 12 attached to the column 6 is omitted.

Next, the operation of the shield machine 20 configured as described above will be described. The excavation of the cutting face is performed by rotating the main cutter 1 while feeding high-pressure muddy water from a mud feed port 14a of a mud feed pipe 14 provided on the upper horizontal frame 5A, and a segment assembled in a ring shape by the shield propulsion jack 10. Press 11 to move the shield machine 20 forward. At this time, excavation of a long hole extending in the upper and lower horizontal directions by the sub-cutter 5k provided in the upper and lower horizontal frames 5A and 5B is performed at the same time. Excavated earth and sand
The slurry is stirred together with the mud by the main cutter 1 and the agitator 16, and is sent from the mud outlet 15 a through the mud pipe 14 to a sludge treatment device (not shown) outside the shield machine 20. When the excavation of one segment width is completed, the segment 11 is assembled using the erector 12 at the rear of the shield machine 20. A tail seal 13 is attached to a gap between the segment 11 and the shield machine 20 so as to prevent earth and sand and water from entering.

FIG. 3 shows a partition wall 4 in the front body of the shield, a column 6 built at right angles inside the middle body of the shield, and upper and lower parts mounted on and below the partition 4 and the column 6, respectively. FIG. 5 is a perspective view showing the configuration of a reinforcing frame composed of the horizontal frames 5A and 5B, and details of the arrangement of a slide jack 7 as a moving mechanism of the left and right widening cylinders 3L and 3R. The four slide jacks 7 are attached to the inside of the shield of the horizontal frames 5A and 5B, four at the top and four at the bottom.
Front and rear to move the right wide body slide jacks 7R and 7r, and the front and rear to move the left wide body 3L.
It consists of the rear two left body slide jacks 7L, 7l,
The right body slide jacks 7R, 7r and the left body slide jacks 7L, 7l are arranged alternately in the front and rear directions.
In FIG. 1, reference numeral 5P denotes a partition of the horizontal frames 5A and 5B, which are upper and lower trunks, and is formed integrally with the partition 4 (omitted in FIG. 1A). FIG. 4 is a perspective view showing a shield body (left and right widening bodies 3L, 3R) moving left and right in the shield excavation direction by the slide jack 7, and a main cutter is provided at the rear of the partition wall 4. Moving partition 3 having a rectangular notch for avoiding one of the shafts
p and 3q are located so as to overlap with the partition wall 4.
In addition, a plate-like extension extending in the axial direction of the shield is formed at the rear part of each of the moving bulkheads 3p and 3q, and above and below the left and right widening cylinders 3L and 3R, A jack receiving portion 3x for receiving the distal end portion of the slide jack 7 is provided at a position corresponding to the distal end portion of the slide jack 7 on the inner end surface of the extension portion inside the shield.
The slide jack 7 pushes the jack receiving portion 3x leftward and rightward of the shield, respectively, so that the left and right widening cylinders 3L and 3R move leftward and rightward, respectively, and the shield trunk 3 widens left and right. Is done. In addition, the moving partition walls 3p, 3
A water stop seal (not shown) is provided at a moving portion at the time of widening such as between q and the partition wall 4.

FIG. 5A is a view showing an example of the slide jack 7. The slide jack 7 extends and contracts a rod 7p by a cylinder 7a housed in a guide member 7b, and is shown in FIG. 5B. So, shield machine 20
Before and after the slide jacks 7R, 7L, 7r, 7
The amount of expansion and contraction of each rod 7p is appropriately set, and the amount of widening in the front and rear directions of the shield body (left and right widening bodies 3L and 3R) is changed. Note that even when the left and right widening cylinders 3L and 3R are not parallel, the jack receiving portion 3x is pressed uniformly,
The tip 7x of the rod 7p is formed as a curved surface so that the left and right widening cylinders 3L and 3R can move smoothly.
Reference numeral 7q denotes a receiving portion of the movable partition walls 3p and 3q, which is normally in contact with the jack receiving portion 3x.

FIGS. 6A and 6B are a front view and a sectional view taken along the line AA (see FIG. 1) of the shield machine 20 when the widening section is constructed. 3R is moved left and right by the slide jack 7 described above,
The over-digging device 2 provided on the main cutter 1 is driven to perform left and right widening excavation. Excavation device 2 is shown in FIG.
As shown in (a), an excavating cutter 2b is attached to the tip of an expanding and contracting arm 2a, and one excavating cutter 2b is attached to each of the symmetrical positions of the main cutter 1. Left and right widened cylinders 3L, 3R
Main cutter 1
The length of the arm 2a is controlled in synchronization with the rotation of the arm. At this time, the movable partition walls 3p and 3q are widened to the left and right while overlapping with the partition wall 4. Since the shield excavator 20 is reinforced by the above-mentioned reinforcing frame, the rigidity of the shield excavator 20 as a whole is high, and therefore, it is possible to sufficiently receive the reaction force received by the left and right widening cylinders 3L and 3R during widening excavation. it can.

FIG. 6 (c) is a view showing the state of the shield machine 20 during the widening construction in the sectional view taken along the line BB (see FIG. 1). The slide jack 71 pushes the left widening cylinder 3L and the right widening body slide jack 7r pushes the right widening cylinder 3R to the left and right, respectively.
At this time, the respective propulsion jacks 10 arranged inside the left and right widening cylinders 3L, 3R move left and right, respectively, integrally with the widening cylinders 3L, 3R. When the excavation of one segment width is completed, the segment 1
Assemble 1. FIG. 7A is a diagram illustrating a digging shape of a general portion by the shield machine 20, and FIG. 7B is a diagram illustrating a digging shape of the widened portion. In the figure, a backfill material made of a mixture of cement, water glass and the like is injected and filled into a tail void 17v (hatched portion in the figure) generated by excavation by the subcutter 5k. Further, as described later, the segment 11 used for the general portion and the widening portion is used in accordance with the excavation shape of the tunnel.

FIG. 8 shows a shield machine 2 according to the present embodiment.
FIG. 4 schematically shows how to excavate a tunnel 18 provided with a tapered portion in the excavation direction using 0, and the amount of widening of the shield body 3 in the left and right directions is measured before the shield excavator 20. Since it can be changed in the backward direction, the entire shield excavator 20 can be moved along the tunnel shape. Therefore, the amount of extra excavation can be reduced, and as a result of excavation,
The clearance between the shield machine and the ground can be reduced.

FIG. 9A is a diagram showing a state where the segment 11 is assembled on a general portion having a circular cross section, and FIG. 9B is a diagram showing a state where the segment 11 is assembled on a tapered portion or a widened portion. is there. In the general part, the segments 11A, which are RC segments made of concrete material reinforced with reinforcing steel,
11B and 11K are used, and the segments 11A and 11K and the steel segments 11M and 11N are used in the tapered portion or the widened portion. The segments 11A, 11B and 11K are shown in FIG.
As shown in (a), the segment is an arc-shaped segment having a fixed segment shape, and the segment K is a segment 11A, 1
1B is a segment which is inserted between adjacent segments after being connected to each other with a ring bolt (not shown) and assembled into a ring shape, and connected by a ring bolt. The ring bolts are tightened so that force is transmitted between the assembled segments. The segment 11B is a segment adjacent to the segment K and has substantially the same shape as the segment 11A. However, the segment 11B is tapered in the insertion direction on the side of the connection portion with the segment K so that the segment K can be inserted. The segments 11M and 11N are, as shown in FIG.
A segment having a horizontal portion 11y between two arc portions 11x, a segment 11M is a segment adjacent to the front side of the segment K clockwise in a cross section, and a segment 11N is a segment adjacent to the rear side of the segment K. . The length of the horizontal portion 11y of each of the segments 11M and 11N is set to a length corresponding to the left and right widening amounts of the tunnel. For example, in a location where the widening amount is large as shown in FIG. Long segment 11M, 1
1N (shaded area in the figure) is used. In a tunnel section having a horizontal portion on the upper or lower side, a large bending moment is generated in the horizontal portion, but the segments 11M and 11N
As described above, since there is no joint portion that crosses the horizontal portion, the rigidity of the assembled segment is large, and sufficient strength performance can be secured against the bending moment. Further, since the segments 11M and 11N are made of steel, the weight is lighter than that of the RC segment, and the handling is easy even when the horizontal portion is long.

As described above, according to the present embodiment, the upper and lower horizontal frames 5A and 5B having the sub cutter 5k on the front surface and the upper and lower horizontal frames 5A and 5B are provided.
B, a tunnel machine 18 having a tapered portion is excavated by a shield machine 20 having left and right widened cylinders 3L and 3R provided between the two arcs, and two arcs are used as segments used for the widened portion or the tapered portion. Since the variable-section shield is reinforced using the segments 11M and 11N having the horizontal portion 11y between the portions 11x, sufficient strength performance can be secured against the bending moment acting on the horizontal portion of the widened portion. .

In the present embodiment, a support is provided inside the shield middle body, and a shield excavator having a structure having horizontal frames 5A and 5B above and below the support and the partition wall is formed. Although the method of lining the cross-sectional shape has been described, even a substantially oval cross-sectional shape such as the above-described conventional cross-sectional shape (FIG. 14A) has sufficient strength performance as in the above-described embodiment. Work can be performed. That is, as shown in FIG. 12A, as the segments used for the widened portion, the segments 11A and 11K on the normal arc forming the side circle portion, the two arc portions 11r, and the two arc portions 11r are provided. 11P and 11Q (see FIG. 12 (b)), which are composed of a horizontal portion 11s provided in
Is used. The segment adjacent to the segment K was defined as a segment 11P. This segment 11P, 1
1Q is similar to segments 11M and 11N described above.
Since there is no joint portion that crosses the horizontal portion, the rigidity of the assembled segment is large, and sufficient strength performance against bending moment can be secured. Further, the segments 11P and 11Q are also the segments 11M and 1M.
As in the case of 1N, if the segment is made of steel, the handling becomes easy even when the horizontal portion becomes long.

[0018]

As described above, according to the first aspect of the present invention, a segment having a linear portion having a length corresponding to the widening amount is used as a segment used for a portion including a linear portion of a cross section of a widening portion. In other words, since the variable section shield is reinforced using a segment that does not have a joint portion that crosses the horizontal portion, the rigidity of the assembled segment can be increased, and the bending moment can be reduced. Sufficient strength performance can be secured.

According to the second aspect of the present invention, since the segment is composed of two arc portions and a horizontal portion formed between the two arc portions, it is used for a normal shield. The segments can be easily assembled by combining with arc segments.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a shield machine according to an embodiment of the present invention.

FIG. 2 is a sectional view of the shield machine according to the embodiment of the present invention.

FIG. 3 is a diagram showing a frame structure of the shield machine according to the embodiment of the present invention.

FIG. 4 is a diagram showing a widening cylinder of the shield machine according to the embodiment of the present invention.

FIG. 5 is a diagram for explaining a mechanism for moving the widening cylinder according to the embodiment of the present invention.

FIG. 6 is a diagram showing a front view of the shield machine when widening and a cross section of the shield body.

FIG. 7 is a diagram showing an excavation shape by the shield machine according to the embodiment.

FIG. 8 is a diagram showing a state of excavation in a tapered portion of the shield excavator according to the embodiment.

FIG. 9 is a diagram showing an assembled state of segments according to the embodiment of the present invention.

FIG. 10 is a diagram showing an example of a segment shape according to the embodiment of the present invention.

FIG. 11 is a diagram illustrating a segment assembled state according to the embodiment of the present invention.

FIG. 12 is a diagram showing a segment assembled state in another excavation cross-sectional shape.

FIG. 13 is a view for explaining a conventional enlarged shield method.

FIG. 14 is a diagram showing a cross section of a widened portion of a tunnel and a state of assembling segments in a conventional widened portion.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Main cutter 2 Overhanging device 3 Shield trunk 3L Left widening cylinder 3R Right widening cylinder 4 Partition wall 5A, 5B Horizontal frame 6 Post 7 Slide jack 8 (Main cutter) shaft 9 (Main cutter) drive 10 Shield propulsion jack 11 Segment 12 Elector 13 Tail seal 14 Mud feed pipe 15 Drain pipe 16 Agitator 20 Shield excavator

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Shin Koda 2-1 Tsukudo-cho, Shinjuku-ku, Tokyo Tokyo, Japan Kumagaya Gumi Corporation (72) Inventor Tomoo Mimura 2-1 Tsukudo-cho, Shinjuku-ku, Tokyo Stock Company Kumagaya Gumi Tokyo head office

Claims (2)

[Claims] 1. A variable cross-section shield having a widened portion, wherein a segment having a straight portion having a length corresponding to the widening amount is used as a segment used for a portion including a straight portion of a cross section of the widened portion. Lining structure of variable section shield. 2. The lining structure for a shield having a variable cross section according to claim 1, wherein said segment comprises two arc portions and a horizontal portion formed between said two arc portions.