JP3253870B2 - How to assemble the turtle shell segment - 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 a tortoise-shaped segment for lining a tunnel wall excavated by a shield method.

[0002]

2. Description of the Related Art Conventionally, in order to apply a segment lining to an excavated wall surface while excavating a tunnel by a shield method, a plurality of rectangular segments curved in the circumferential direction of the tunnel are assembled in the circumferential direction of the tunnel to assemble one ring. A method of forming a tunnel lining part for each minute and sequentially constructing the tunnel lining part in the tunnel length direction, and providing a V-shaped front and rear inclined end face at both ends between front and rear end faces parallel to each other. It is known to perform tunnel lining while assembling turtle shell segments in a staggered manner in the circumferential direction of the tunnel.

[0003] Both the rectangular segment and the tortoise-shaped segment are gripped by an erector provided in a shield excavator and supplied to a predetermined portion of an excavation wall surface. In the case of a rectangular segment, its long side rear end face is already assembled. One ring is connected to the front end face of the opposing segment of the tunnel lining portion by a bolt and a nut, and the short side end faces facing each other are joined and connected in the circumferential direction of the tunnel. The work part is formed. At this time, when forming the tunnel lining, the propulsion jack of the shield excavator is contracted, and after assembling the tunnel lining for one ring, the propulsion jack is pressed against the front end face of the tunnel lining to excavate the shield. The machine is digging.

On the other hand, in the case of a tortoise-shaped segment, the torso-shaped segments which are opposed to each other in the circumferential direction of the tunnel are alternately joined and connected to each other, and the tortoise-shaped segments are sequentially assembled in a staggered manner in the circumferential direction of the excavation wall. By this assembly, the trapezoidal portion which is the first half of the tortoiseshell-shaped segment projects alternately in the circumferential direction, and the same shaped space is formed between the projecting trapezoidal portions. The trapezoid-shaped segment to be assembled is fitted with the trapezoidal rear half portion, and the rear end portion of the turtle-shaped segment is joined to the end surface of the turtle-shaped segment exposed in the space,
Connected. At this time, it is possible to continuously excavate the shield excavator without stopping by pressing the propulsion jack against the front end face of the torso-shaped segment other than the torso-shaped segment to be assembled.

[0005]

However, in the former tunnel lining with a rectangular segment, the lining portion for one ring is formed intermittently, so that it is necessary to construct a long-distance tunnel. Not only takes a long time, but when forming the next lining part on the front end face of the previously assembled lining part, use the rear end face of the rectangular segment as the front end face of the existing lining part. This is a work process in which the rectangular segments are sequentially supported along with the circumferential connection on the front end face of the existing lining portion while being once supported by the existing lining portion. The propulsion force of the shield excavator and the earth pressure of the surrounding ground are not acting on the forged part, so the connection of the new lining part to the existing lining part is temporarily tightened to the last, Received earth pressure It is necessary to perform again this tightening in Thailand.

[0006] On the other hand, in the latter case of the tunnel lining with the tortoise-shaped segments, as described above, the front and rear inclined end faces of the torso-shaped segments facing in the circumferential direction of the tunnel are alternately joined and connected to each other in the circumferential direction of the excavated wall surface. Since the turtle shell segments are assembled in a staggered sequence, it is possible to continuously excavate without stopping the shield excavator, and if the existing turtle shell segments are fully tightened, they should be assembled next The tortoiseshell-shaped segments can be connected while being fully tightened.

SUMMARY OF THE INVENTION The present invention is intended to efficiently connect a newly-installed turtle-shaped segment to an existing turret-shaped segment by using a pressing force of a propulsion jack of a shield excavator when assembling the turtle-shaped segment. It is intended to provide a method of assembling a tortoiseshell-shaped segment for the purpose of doing so.

[0008]

According to a first aspect of the present invention, there is provided a method for assembling a turtle-shaped segment according to the first aspect of the present invention, in which the front and rear inclined end faces of the turret-shaped segment facing in the circumferential direction of the tunnel are alternately joined to each other. A method of constructing a segment lining by sequentially assembling a tortoise-shaped segment on a tunnel wall excavated by a shield excavator while connecting, wherein a front end surface of the tortoise-shaped segment and a front inclined end surface on both sides of the front end surface. To the rear inclined end face,
The trapezoidal rear half of the tortoise-shaped segment to be assembled next was fitted into the trapezoidal space formed by the front inclined end of the connected tortoise-shaped segment, and the propulsion jack was pressed against the front end face of this tortoise-shaped segment. In this state, a joint bolt is inserted from the front end side of the tortoise-shaped segment into the oblique insertion hole penetrating the rear inclined end surface in parallel with the front inclined end surface, and the tip of the joint bolt is inserted into the trapezoidal space. Characterized by performing a work of screwing into a screw hole provided on the front inclined end surface of the tortoiseshell-shaped segment forming the hypotenuse.

According to a second aspect of the present invention, the front and rear inclined end faces of the tortoise-shaped segments facing each other in the circumferential direction of the tunnel are alternately joined and connected to each other, and the tortoise-shaped segments are sequentially staggered on the tunnel wall excavated by the shield excavator. In the method of constructing the segment lining by assembling, the front inclined surface of the tortoise-shaped segment and the front inclined end of the torso-shaped segment connected to and joined to the front inclined end surface on both sides of the front end surface The trapezoidal rear half of the tortoise-shaped segment to be assembled next is fitted into the formed trapezoidal space, and the propulsion jack of the shield excavator is pressed against the center of the front end face of the tortoise-shaped segment. A joint bolt is inserted into the oblique insertion hole penetrating from the both sides of the front end face to the rear slope end face in parallel with the front slope end face. The front end of the hand bolt is screwed into a screw hole provided on the front inclined end surface of the tortoiseshell-shaped segment forming the hypotenuse of the trapezoidal space, and then the front end of this tortoiseshell-shaped segment is screwed with the joint bolt. The present invention is characterized in that propulsion jacks arranged on both sides of the propulsion jack are pressed against both sides of the surface.

According to a third aspect of the present invention, there is provided another method of assembling the tortoiseshell-shaped segments. In the assembling method according to the second aspect, the front ends of the existing tortoiseshell-shaped segment rows connected to each other in the tunnel circumferential direction. With the propulsion jack of the shield excavator pressed against the center of the front end face of the tortoise-shaped segment fitted in the trapezoidal space formed on the surface, the front end face of the tortoise-shaped segment is parallel to the front inclined end face from both sides. The joint bolt was inserted into the oblique insertion hole penetrating the rear inclined end surface, but in this method, the shield excavator was attached to one side of the front end surface of the tortoise-shaped segment fitted in the trapezoidal space. With the propulsion jack pressed, a joint bolt is inserted from the other end of the front end face of the tortoise-shaped segment into the oblique insertion hole passing through the rear inclined end face in parallel with the front inclined end face. The tip is screwed into a screw hole provided on the front inclined end face of the torso-shaped segment forming one oblique side of the trapezoidal space portion, and then the front end face and the like of this tortoise-shaped segment screwed with the joint bolt Push the propulsion jack of the shield excavator against the side and then retreat the propulsion jack pressed against one side of the front end face, or retreat the propulsion jack pressed against one side of the front end face and then move the front end face Push the propulsion jack against the other side.Insert a joint bolt from one side of the front end face into the oblique insertion hole that passes through the rear slope end face in parallel with the front slope end face. Is screwed into a screw hole provided on the front inclined end face of the torso-shaped segment forming the other oblique side of the trapezoidal space portion, and then all the propulsion jacks facing the front end face of this tortoise-shaped segment are removed. Press on the front end It is characterized in that the shed.

[0011]

[Operation and effect] When the tortoise-shaped segments are sequentially joined and connected to each other in the circumferential direction of the tunnel, the front half trapezoidal portions of every other tortoise-shaped segment are projected, and A trapezoidal space is formed between the trapezoidal projections. The rear half of the tortoise-shaped segment is fitted into this trapezoidal space, and the rear end surface and the rear inclined end surface are exposed to the trapezoidal space. It is joined to the front inclined end face of an existing tortoise-shaped segment adjacent in the circumferential direction of the continuous tunnel.

The tortoiseshell-shaped segment is provided with oblique insertion holes for joint bolts penetrating from both sides of the front end face to the rear inclined end faces in parallel with the front inclined end faces, respectively, and at both front inclined end faces. Since the screw holes for screwing the joint bolts are provided, when the rear half of the new turtle-shaped segment is fitted into the trapezoidal space, the oblique insertion holes on both sides of the turret-shaped segment form the hypotenuse of the trapezoidal space. Can be communicated with the screw holes for joint screwing provided on the front inclined end surfaces of the existing turtle shell segments on both sides.

In this state, the propulsion jack is pressed against an appropriate position of the front end face of the newly-developed tortoise-shaped segment, and penetrates from the front end side of the torso-shaped segment to the rear inclined end face in parallel with the front inclined end face. Inserting a joint bolt into the oblique insertion hole, and screwing the end of the joint bolt into a screw hole provided on the front inclined end face of the tortoise-shaped segment forming the oblique side of the trapezoidal space. It is.

In the method for assembling the tortoiseshell-type segment, the invention according to claim 2 is to press a propulsion jack of a shield excavator against the center of the front end face of the newly-provided tortoiseshell-type segment. The shield excavator is excavated by supporting the reaction force on the front end face of the tortoiseshell-shaped segment by extending the other propulsion jack pressing against the lining front end face assembled by the mold segment. At this time, the propulsion jacks provided on the front side of the oblique insertion holes that are opened on both sides of the front end face of the newly-developed tortoise-shaped segment are contracted, and these oblique insertions are performed during the excavation of the shield excavator. A joint bolt is inserted into the hole and screwed into a screw hole provided in an existing tortoiseshell-shaped segment.

[0015] This screwing operation is performed in a state in which the newly provided tortoise-shaped segment is pressed against the existing torso-shaped segment by the propulsion jack, so that the new tortoise-shaped segment and the existing torso-shaped segment are connected by joint bolts. Is performed firmly, and final fastening becomes possible. The open end of the oblique insertion hole is formed with a large diameter, and the joint bolt is screwed into the screw hole in a state where the large diameter bolt head of the joint bolt is locked in the large diameter hole. Things. When the connection work between the new tortoise-shaped segment and the existing tortoise-shaped segment by connecting bolts through the oblique insertion holes on both sides is completed, the propulsion jacks arranged in front of these oblique insertion holes are extended to newly install them. The turtle shell segment is pressed against both sides of the front end face screwed by the joint, and is used for propulsion of the shield excavator.

According to the third aspect of the present invention, the joint work between the new turtle shell type segment and the existing turtle shell type segment by the joint bolt is performed in a trapezoidal space having the rear half formed on the front end face of the existing turtle shell type segment. With the propulsion jack of the shield excavator pressed against one side of the front end face of the newly fitted turtle-shaped segment, it penetrates from the other front end face of the turtle-shaped segment to the rear inclined end face in parallel with the front inclined end face. The joint bolt is inserted into the oblique insertion hole, and the tip of the joint bolt is screwed into a screw hole provided on the front inclined end surface of the tortoise-shaped segment forming one oblique side of the trapezoidal space. Then, after pushing the propulsion jack of the shield excavator against the other end of the front end face of the tortoiseshell-shaped segment, the propulsion jack pressed against one side of the front end face is retracted or pressed to one side of the front end face. After the applied jack is retracted, the jack is pressed against the other side of the front end face.From one side of the front end face to the oblique insertion hole passing through the rear slope end face in parallel with the front slope end face. A joint bolt is inserted, and the tip of the joint bolt is screwed into a screw hole provided on the front inclined end face of the shell-shaped segment forming the other oblique side of the trapezoidal space portion. Alternatively, all of the propulsion jacks facing the front end face of the above can be pressed against the front end face.

In any of the above methods of assembling the tortoise-shaped segment, the front end of the new tortoise-shaped segment is fitted into a trapezoidal space formed at the front end of the existing tortoise-shaped segment, and the propulsion jack of the shield excavator is used. The joint bolts are screwed into the existing turret-shaped segments through the oblique insertion holes penetrating the turret-shaped segments in the state pressed by the turret-shaped segments, so that the connection between the turret-shaped segments is extremely strong and the The mold segments can be sequentially tightened.

At this time, since the oblique insertion holes are formed to extend from both sides of the front end face of the tortoise-shaped segment to the rear inclined end faces on both sides in parallel with the front inclined end face, respectively, and are connected by joint bolts. While using the front end face other than the oblique insertion hole part where the work is being performed as the pressing surface of the propulsion jack,
The joint bolts can be tightened smoothly and reliably. In addition, screw holes for screwing the joint bolts are provided on the front inclined end faces on both sides of the tortoise-shaped segment, so the new tortoise-shaped segment is trapezoidal. When fitted into the space, the oblique insertion holes on both sides thereof can be matched with the screw holes for screwing of the existing turtle-shaped segments, and the turtle-shaped segments can be connected accurately and efficiently.

When the new tortoise-shaped segment is brought into contact with the front end face of the existing tortoise-shaped segment, horizontal through holes communicating with each other in the lengthwise direction of the tunnel are provided between the front and rear end faces of the tortoise-shaped segment. In this case, the front and rear tortoiseshell segments can be integrally connected to each other by a large-diameter head joint bolt having a screw hole in the horizontal through hole. This connection operation can be performed while pressing the propulsion jack of the shield excavator against the front end face of the turtle-shaped segment other than the portion where the connection operation is performed by the joint bolt as described above.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the drawings, a specific embodiment of the present invention will be described. FIG. 1 is a perspective view of a turret-shaped segment 1 made of reinforced concrete having a constant thickness, and its outer peripheral shape is parallel to each other. Front and rear end faces 2 and 3 of the same length
And front and rear inclined surfaces 4 and 5 of the same length, which are V-shaped between both side ends of the front and rear end surfaces 2 and 3, and are opposed to each other. And the entire shape is changed to its front end surfaces 2, 3
Curved in the length direction of the tunnel along the curved excavation surface in the circumferential direction of the tunnel.

The turtle shell-shaped segment 1 is provided with oblique insertion holes 6, 7 penetrating through the rear inclined end faces 5, 5 from both sides of the front end face 2 in parallel with the front inclined end faces 4, 4, respectively. And between these front and rear end faces 2 and 3
Horizontal through holes 8 and 9 are provided parallel to each other at a predetermined interval from both sides of the center of the side 3 and a center line is provided at the center of the front inclined end surfaces 4 and 4 at the center. Screw holes 10 and 11 are provided parallel to the inclined end surfaces 5 and 5. The positions where the screw holes 10 and 11 are formed are such that the lengths of the inclined front surfaces 4 and 4 reaching the screw holes 10 and 11 from both ends of the front end face 2 are the same as those of the front and rear inclined end faces 4 and 5. To the rear inclined end face 5
Are provided at positions equal to the side lengths of the rear inclined end surfaces 5 up to the oblique insertion holes 6 and 7, respectively.

The open ends of the oblique insertion holes 6, 7 and the horizontal through holes 8, 9 opened on the front end surface of the tortoiseshell-shaped segment 1 are connected to the oblique insertion holes 6, 7, and the horizontal through holes 8, 9, respectively. Large-diameter locking holes 6a to 9a for inserting and locking the large-diameter heads 12a, 13a of the joint bolts 12, 13 (shown in FIG. 4) respectively inserted therethrough.
Are formed respectively. In addition, the front and rear inclined end surfaces 4, 5
Are provided on both sides thereof with a projection 14 and a recess 15 having a shape in which the projection 14 can be fitted.
An erector gripping hole 16 is provided at the center of the curved inner surface of the.

The method of assembling the tortoise-shaped segment 1 constructed as described above on the tunnel wall surface excavated by the shield excavator 21 will be described. The shape of the front end face of the lining by the turtle shell type segment 1 is
As shown in the development views of FIG. 2 and FIG. 5, the tortoise-shaped segments 1, 1,... 1 are sequentially joined and connected in a staggered manner in the circumferential direction of the tunnel. The front half-trapezoidal portions of every other tortoiseshell-shaped segment 1 are disposed forward in the circumferential direction of the tunnel, and are located between the opposed front inclined end faces 4, 4 of these tortoise-shaped segments 1, 1. A trapezoidal space portion 17 having the same shape as that of the rear half of the tortoiseshell-shaped segment 1 is formed. Further, the front and rear end faces 2, 3 of the tortoiseshell-shaped segments 1, 1 are joined and connected in the lengthwise direction of the tunnel.

From this state, a shield is provided on the front end face 2 of the other tortoise-shaped segment 1 other than any trapezoidal space portion 17 into which a tortoise-shaped segment to be next assembled (hereinafter referred to as a new tortoise-shaped segment 1A) is fitted. The spreaders of the plurality of propulsion jacks 22 mounted on the excavator 21 are received, and the propulsion jacks 22 corresponding to the trapezoidal space portions 17 are contracted to set the erectors 23 in the trapezoidal space portions 17. At the same time, the assembling work is carried out by fitting the rear trapezoidal portion of the new turtle shell type segment 1A using the above, and at the same time, the propulsion jack 22 supported on the front end face 2 of the existing turtle shell type segment 1 is extended to The excavation of the tunnel is continued by allowing the front end face 2 to receive the propulsion reaction force and excavating the shield excavator 21.

The shield excavator 21 is, as shown in FIG.
The front trunk 24 and the rear trunk 25 are connected to each other via a direction correcting jack 26 so as to be freely bent, and a partition wall 27 stretched over the front trunk 24.
A cutter head 29 rotatably driven by a motor 28 is rotatably supported, and further, has a known structure in which the propulsion jack 22 and the erector 23 are disposed on the rear body 25. As shown in FIG. 3, for example, as shown in FIG. 3, when assembling a lining for one ring that makes one round on the excavation wall by six tortoise-shaped segments 1, six sets of propulsion jacks are set with three sets. 22 are provided corresponding to the front end surfaces 2 of the six tortoise-shaped segments 1, respectively.

Therefore, as described above, each of the front end faces 2 of the tortoiseshell-shaped segments 1 other than the front end face 2 of the tortoiseshell-shaped segment 1 exposed to the trapezoidal space portion 17 where the new tortoiseshell-shaped segment 1A is to be assembled. A propulsion jack 22 is pressed against the center and both sides of the front end face 2 of each turtle-shaped segment. When the new turtle-shaped segment 1A is fitted into the trapezoidal space 17, three propulsions corresponding to the front end surface 2 of the existing turret-shaped segment 1 forming the inner bottom surface of the trapezoidal space 17 are provided. The jack 22 is contracted as shown in FIG. 5, and the space between the spreader of these propulsion jacks 22 and the front end face of the existing tortoiseshell-shaped segment 1 is used, as shown in FIG. Part is trapezoidal space part
Fit into 17 using erector 23.

By this fitting, the rear end face 3 of the new tortoiseshell type segment 1A is joined to the front end face 2 of the tortoiseshell type segment 1 forming the inner bottom surface of the trapezoidal space portion 17, and the rear side of the new tortoiseshell type segment 1A. The two inclined end surfaces 5, 5 are respectively joined to the opposing front inclined end surfaces 4, 4 of the turtle-shaped segments 1, 1 forming the inclined side surfaces of the trapezoidal space portion 17, and furthermore, the slope of the new turtle-shaped segment 1A is Row insertion hole 6,
7 communicates with screw holes 10, 11 provided in the front inclined end faces 4, 4 of the tortoise-shaped segments 1, 1 facing each other. FIG. 4 shows a state immediately before the new turtle shell type segment 1A is fitted into the trapezoidal space portion 17. Further, the projections 14 and the recesses 15 provided on the front inclined end surfaces 4 of the existing tortoise-shaped segments 1 and 1 are provided.
At the same time, the concave portion 15 and the projection 14 provided on the rear inclined end face 5 of the new tortoiseshell type segment 1A are fitted and locked to each other, and the new tortoiseshell type segment 1A is laid at a predetermined lining position with respect to the existing tortoiseshell type segment 1. Can be joined accurately.

When the work of inserting the new tortoiseshell-shaped segment 1A into the trapezoidal space portion 17 is completed, the center propulsion jack 22 of the three propulsion jacks 22 which has been contracted is immediately extended and newly constructed as shown in FIG. Tortoiseshell segment 1A
Of the front end face 2 between the horizontal through holes 8 and 9. In this state, the existing tortoise shell to which the joint bolts 12 and 13 are inserted into the oblique insertion holes 6 and 7 of the new tortoiseshell type segment 1A and the rear inclined end surfaces 5, 5 on both sides of the new tortoiseshell type segment 1A are joined. The new tortoiseshell-shaped segments 1A are integrally connected to the existing tortoiseshell-shaped segments 1 and 1 by screwing them into screw holes 10 and 11 provided on the front inclined end surfaces 4 and 4 of the mold segments 1 and 1 (see FIG. 8).

Next, as shown in FIG. 9, horizontal through holes 8 on both sides penetrating between the front and rear end surfaces of the new tortoiseshell-shaped segment 1A,
9 is a horizontal through-hole of the tortoise-shaped segment 1 which is joined to the rear end face 3 of the new tortoise-shaped segment 1A by inserting large-diameter headed joint bolts 18 and 19 having screw holes 18b and 19b into the newly formed tortoise-shaped segment 1A. Screw holes 18b, 19b of large diameter heads 18a, 19a of joint bolts 18, 19 inserted through 8, 9 are screwed respectively. Joint bolts 18, 19 inserted in the horizontal through holes 8, 9
The tortoiseshell-shaped segments 1 and 1A are sequentially connected to each other in the tunnel length direction, and the tortoiseshell-shaped segments 1 and 1A are sequentially connected to each other in the circumferential direction of the tunnel by the joint bolts 12 and 13 inserted into the oblique insertion holes 6 and 7. .

As described above, while the propulsion jack 22 is pressed against the center of the front end face of the new tortoiseshell-shaped segment 1A, the connection of the new tortoiseshell-shaped segment 1A to the existing tortoiseshell-shaped segment 1 is performed, and after the work is completed. As shown in FIG. 10, the propulsion jacks 22 and 22 provided on both sides of the central propulsion jack 22 are extended so that the new
Of the shield excavator 21. Subsequently, the second half of the new tortoiseshell-shaped segment 1A is fitted into the next trapezoidal space portion 17 in the same manner as described above, and connected to the existing tortoiseshell-shaped segment 1 in the same work order as described above. Mold segment 1
In the tunnel circumferential direction and the tunnel length direction to perform tunnel lining.

In the above embodiment, the joint bolt 1 of the new turtle shell type segment 1A to the existing turtle shell type segment 1
The connection work in the circumferential direction of the tunnel by 2 and 13 presses the center propulsion jack 22 of the three propulsion jacks 22 corresponding to the front end face 2 of the new tortoiseshell-shaped segment 1A against the center of the front end face 2, The joint bolts 12, 13 are inserted into the oblique insertion holes 6, 7 on both sides while the propulsion jacks 22, 22 on both sides are contracted.
Was inserted into the existing turtle-shaped segment 1 and the joint bolt was inserted into the other oblique insertion hole while the propulsion jack 22 was pressed against the front end face 2 on the one oblique insertion hole side. The connection operation may be performed. In this case, two propulsion jacks 22 may be provided for each turtle-shaped segment.

That is, as shown in FIG. 11, while the propulsion jack 22 corresponding to this portion is pressed against one side of the front end face of the newly-developed tortoiseshell-shaped segment 1A, it is connected to the oblique insertion hole 7 on the other side of the front end face. The bolt 13 is inserted and screwed into the screw hole 11 provided on the front inclined end face of the turtle-shaped segment 1 communicating with the oblique insertion hole 7. Next, the propulsion jack 22 corresponding to this portion is pressed against the other side of the front end face on the side of the oblique insertion hole 7 into which the joint bolt 13 is inserted, and then the propulsion jack 22 pressed against one side of the front end face. Or the propulsion jack 22 pressed against one side of the front end face is retracted, and then the propulsion jack 22 is pressed against the other side of the front end face. As shown in FIG. A screw hole provided in the front inclined end face of the tortoiseshell-shaped segment 1 communicating with the skew insertion hole 6 by inserting the joint bolt 12 into the skew insertion hole 6 provided in the portion.
It is screwed to 10.

At this time, if the propulsion jack 22 is also provided at the center, the central propulsion jack 22 is pressed against the center of the front end face of the new turtle shell type segment 1A. After completion of the connection work, the propulsion jack 22 that was retracted is replaced with the newly
And presses against one side of the front end face of the torch for use in propulsion of the shield excavation tortoiseshell type segment 21. The operation of inserting the joint bolts 18 and 19 into the horizontal through holes 8 and 9 to connect the tortoise-shaped segments 1 and 1A to each other in the lengthwise direction of the tunnel is the same as in the above embodiment.

[Brief description of the drawings]

FIG. 1 is a perspective view of a tortoiseshell segment,

FIG. 2 is a simplified longitudinal side view of a shield excavator performing tunnel lining,

FIG. 3 is an arrangement front view of a propulsion jack,

FIG. 4 is a sectional view showing a connected state of the tortoiseshell-shaped segments;

FIG. 5 is a simplified development view of an existing tortoiseshell-shaped segment having a trapezoidal space portion,

FIG. 6 is a simplified development view of a state in which a newly-developed tortoiseshell-shaped segment is fitted into a trapezoidal space,

FIG. 7 is a simplified development view of a state where the central propulsion jack is pressed.

FIG. 8 is a simplified development view of a state in which a tortoiseshell-shaped segment is connected by a joint bolt through an oblique insertion hole,

FIG. 9 is a simplified development view of a state in which the turtle-shaped segments are connected to each other by a joint bolt through a horizontal through hole;

FIG. 10 is a simplified development view showing a state in which connection has been completed;

FIG. 11 is a simplified development view for explaining another assembling method of the tortoiseshell-shaped segment of the present invention;

FIG. 12 is a simplified development view showing the next step in FIG. 11;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Tortoise shell type segment 2, 3 Front and rear end face 4, 5 Front and rear inclined end face 6, 7 Skew insertion hole 8, 9 Horizontal through hole 10, 11 Screw hole 12, 13 Joint bolt 17 Trapezoid space 22 Propulsion jack

────────────────────────────────────────────────── ─── Continuation of front page (56) References JP-A-7-62989 (JP, A) JP-A-5-156893 (JP, A) JP-A-3-286098 (JP, A) JP-A-4- 136499 (JP, A) JP-A-2-136493 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) E21D 11/08 E21D 11/04

Claims (3)

(57) [Claims] 1. A segment cover is assembled by sequentially assembling the tortoise-shaped segments on a tunnel wall excavated by a shield excavator while alternately joining and connecting the front and rear inclined end surfaces of the tortoise-shaped segments facing each other in the circumferential direction of the tunnel. In a method for constructing a work, a trapezoidal space formed by a front end face of a tortoise-shaped segment and a front inclined end of a tortoise-shaped segment joined to and joined to a front inclined end face on both sides of the front end face. The trapezoid-shaped segment to be assembled next is fitted into the trapezoidal second half of the segment, and the propulsion jack is pressed against the front end surface of this segment to extend parallel to the front inclined end surface from the front end side of the segment. Insert a joint bolt into the oblique insertion hole that penetrates the rear inclined end face, and form the tip of this joint bolt into the oblique side of the trapezoidal space. A method of assembling a tortoiseshell-shaped segment, comprising performing an operation of screwing into a screw hole provided in a front inclined end face of the tortoiseshell-shaped segment. 2. A segment cover is assembled by sequentially assembling the tortoise-shaped segments on a tunnel wall excavated by a shield excavator while alternately joining and connecting the front and rear inclined end surfaces of the tortoise-shaped segments facing in the circumferential direction of the tunnel. In a method for constructing a work, a trapezoidal space formed by a front end face of a tortoise-shaped segment and a front inclined end of a tortoise-shaped segment joined to and joined to a front inclined end face on both sides of the front end face. The trapezoid-shaped segment to be assembled next is fitted into the trapezoidal second half of the torso-shaped segment, and the propulsion jack of the shield excavator is pressed against the center of the front end face of the tortoise-shaped segment. Insert a joint bolt into the oblique insertion hole penetrating the rear inclined end surface in parallel with the inclined end surface, and insert the tip of the joint bolt Screw into a screw hole provided on the front inclined end face of the tortoise-shaped segment forming the hypotenuse of the trapezoidal space, and then push the propulsion to both sides of the front end face of this tortoise-shaped segment, which is screwed with the joint bolt. A method of assembling a tortoiseshell-type segment, comprising pressing a propulsion jack disposed on both sides of the jack. 3. The segment cover is assembled by sequentially assembling the tortoise-shaped segments on the tunnel wall excavated by the shield excavator while alternately joining and connecting the front and rear inclined end faces of the tortoise-shaped segments facing in the circumferential direction of the tunnel. In a method for constructing a work, a trapezoidal space formed by a front end face of a tortoise-shaped segment and a front inclined end of a tortoise-shaped segment joined to and joined to a front inclined end face on both sides of the front end face. The second half of the trapezoidal shape of the tortoise-shaped segment to be assembled next is fitted into the part, and the other end of the front end of the tortoise-shaped segment is pressed with the propulsion jack of the shield excavator pressed against one side of the front end of the torso-shaped segment Insert the joint bolt into the oblique insertion hole penetrating the rear inclined end surface in parallel with the front inclined end surface from Screw into a screw hole provided on the front inclined end face of the tortoise-shaped segment forming one oblique side of the trapezoidal space portion, and then to the other end of the torso-shaped segment, which is screwed with the joint bolt. After pushing the propulsion jack of the shield excavator, the propulsion jack pressed against one side of the front end face is retracted, or the propulsion jack pressed against one side of the front end face is retracted and then the other side of the front end face Push the propulsion jack into the jack. 面 Insert the joint bolt from one side of the front end face into the oblique insertion hole that passes through the rear slope end face in parallel with the front slope end face. Screw the screw holes provided on the front inclined end face of the tortoise-shaped segment forming the other oblique side of the shape space portion, and then all the propulsion jacks facing the front end face of this tortoise-shaped segment are connected to the front end face. Pushing on Method of assembling a hexagonal shaped segment characterized.