Shield tunneling machine

Abstract

To maximize pull-in amount of a rear drum outer cylinder part.SOLUTION: A shield boring machine consists of a rear drum inner cylinder part 5ba mounted with a shield jack 9b to which a spreader 15 is fitted and a rear drum outer cylinder part 5bb that expands and contracts a rear drum plate 5b. The rear drum outer cylinder part 5bb comprises: first and second fixing member grooves 21, 22 and a transmission member groove 23 that are formed in a circumferential direction on an inner peripheral surface extending backward; a fixing member 17 that is engaged with the first fixing member groove 21 and fixes the rear drum outer cylinder part 5bb to the rear drum inner cylinder part 5ba at a position where length of the rear drum plate 5b is long, and is engaged with the second fixing member groove 22 and fixes the rear drum outer cylinder part 5bb to the rear drum inner cylinder part 5ba at a position where length of the rear drum plate 5b is short; and an expanding and contracting force transmission member 18 that is engaged with the transmission member groove 23 and moves the rear drum outer cylinder part 5bb in an axial direction by expansion and contraction of the shield jack 9b. A concave part 15b, which avoids interference to the fixing member 17 when the shield jack 9b is maximumly contracted, is formed on an opposite surface of a pressing surface of the spreader 15.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a shield tunneling machine.

Background Art

[0002] A shield tunneling machine is known as a device used for excavating a shield tunnel such as a tunnel or a subway by excavating the ground.

[0003] In this shield tunneling machine, a cutter head is rotatably installed at the tip of the skin plate in the advancing direction, and a plurality of bits are arranged circumferentially and radially on the cutter head. Then, by pressing the cutter head against the excavation surface (face) and rotating it while advancing, the ground is excavated in a circular shape. At this time, inside the shield tunneling machine, segments assembled in a cylindrical shape are pushed out behind the skin plate as the shield tunneling machine advances.

[0004] When constructing a curved section of a shield tunnel using such a shield tunneling machine, the shield tunneling machine is bent by a mid-bending jack to conform to the curve.

[0005] Here, at the rear end of the skin plate constituting the shield tunneling machine, a tail seal is provided to seal between the skin plate and the segment in shield construction to prevent groundwater from entering the shield tunneling machine. This tail seal moves as the shield tunneling machine advances while being pressed against the outer peripheral surface of the segment. In addition, the length of shield tunnels is increasing (generally, a length of 1.5 km or more is called a long distance, and a length of 3.0 km or more is called an ultra-long distance). Due to deterioration and damage of the tail seal (such as deformation of the seal member itself, detachment or deformation of the wire brush, etc.) associated with such an increase in the length of the shield tunnel, various troubles such as problems occurring in the segment and abnormal increase in thrust have occurred. Therefore, in order to avoid such troubles, it is necessary to replace the tail seal during tunneling.

[0006] Regarding the curved tunneling of a shield tunneling machine, for example, it is described in Patent Document 1. For the folding mechanism of a shield tunneling machine in which the shield body is divided into two parts front and back and connected in a bendable manner, the skin plates on the inner side of the bend of the front body and the rear body are inscribed on the inner peripheral side of the tunnel wall surface, and the outer side of the bend at the front end of the front body and the outer side of the bend at the rear end of the rear body are moved along the outer peripheral side of the tunnel wall surface to perform sharp curve tunneling. A technique is disclosed.

[0007] Regarding the replacement of the tail seal in a shield tunneling machine, for example, it is described in Patent Document 2. The skin plate of the rear body part is made double, and by tunneling and advancing with the inner skin plate left in the ground, the inner peripheral surface of the outer skin plate that has been covered by the inner skin plate until then is exposed to the inside of the pit, and a new tail seal is attached to this inner peripheral surface from inside the pit. A technique is disclosed.

Prior Art Documents

Patent Documents

[0008]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0009] Now, in the construction of the shield tunnel described above, depending on the construction site, sharp curve tunneling may be required. At this time, depending on the maximum folding angle of the shield tunneling machine, it may be difficult to follow the required sharp curve, or overexcavation may increase.

[0010] In addition, in order to prevent troubles caused by deterioration or damage of the tail seal, it is necessary to perform the replacement work of the tail seal from inside the shield machine during tunneling.

[0011] The present invention has been made in view of the above-described technical background, and an object thereof is to provide a technique capable of smoothly performing curved construction using a shield tunneling machine.

[0012] Further, the present invention has been made in view of the above-described technical background, and an object thereof is to provide a technique capable of performing replacement work of a tail seal of a shield tunneling machine from inside the shield machine.

Means for Solving the Problems

[0013] In order to solve the above problems, the shield tunneling machine of the present invention according to claim 1 includes a front body portion provided with a cutter head, a rear body inner cylinder portion provided with a plurality of shield jacks having spreaders attached to the tips thereof and located on the front body portion side, and a rear body portion having a rear body outer cylinder portion that is installed subsequent to the rear body inner cylinder portion and partially overlaps the rear body inner cylinder portion and is movable in the axial direction. The rear body outer cylinder portion has, on the inner peripheral surface, a first fixing member engaging portion, a second fixing member engaging portion, and a transmission member engaging portion that are respectively formed in the circumferential direction from the front to the rear. A fixing member that detachably engages with the first fixing member engaging portion and fixes the rear body outer cylinder portion to the rear body inner cylinder portion in a first state in which the length of the rear body portion is relatively long, and detachably engages with the second fixing member engaging portion and fixes the rear body outer cylinder portion to the rear body inner cylinder portion in a second state in which the length of the rear body portion is relatively short, and an expansion / contraction force transmission member that detachably engages with the transmission member engaging portion and fixes the spreader of the shield jack to the rear body outer cylinder portion are provided. A concave portion is formed on the surface opposite to the pressing surface of the spreader to avoid interference with the fixing member when the shield jack is maximally contracted. Concavely It is fixed to a fixed base provided on an intermediate ring body annularly provided on the rear barrel inner cylinder part along the inner peripheral surface of the rear barrel inner cylinder part.

Effects of the Invention

[0016] It becomes possible to maximize the amount of retraction of the rear body outer cylinder portion with respect to the rear body inner cylinder portion when the shield jack contracts, and the length of the rear body portion in the second state can be further shortened. ​​

[0017] By moving the rear barrel outer cylinder part from the first state to the second state in this way, it becomes possible to shorten the length of the rear barrel part and smoothly perform the curved construction. Further, if the tail seal is exposed inside the machine by moving the rear barrel outer cylinder part from the first state to the second state, it becomes possible to perform the replacement work of the tail seal from inside the shield machine.

Brief Description of the Drawings

[0018]

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Mode for Carrying Out the Invention

[0019] Hereinafter, embodiments as an example of the present invention will be described in detail with reference to the drawings. In the drawings for explaining the embodiments, the same components are generally denoted by the same reference numerals, and repeated explanations thereof are omitted.

[0020] First, the overall configuration of the shield tunneling machine of this embodiment will be described with reference to FIG. 1. FIG. 1 is a main part configuration diagram showing the inside of the shield tunneling machine of this embodiment seen through from the side.

[0021] The shield tunneling machine 1 of this embodiment is, for example, a mud pressure type shield machine that excavates while generating mud having water impermeability and plastic fluidity (properties that can be freely deformed and moved) by injecting an additive into the earth and sand excavated by the cutter head 2 and kneading it, and filling the chamber 4 between the cutter head 2 and the equipment main body 3, thereby generating a mud pressure that counteracts the face earth pressure and ensuring the stability of the face while performing excavation.

[0022] The cutter head 2 is a shield cutter disk for excavating the ground, and is installed at the front end of the shield tunneling machine 1 in a state where it can rotate in the forward and reverse directions along the circumferential direction of the equipment main body 3.

[0023] On the front surface of this cutter head 2 (the surface facing the face of the tunnel face), a center bit CB, bits B, and scraper tools (not shown) are mounted. The center bit CB and bits B are mainly excavation components for breaking down the ground, and the scraper tools are mainly cutting components for cutting the ground. Note that, for example, roller cutters or the like may be mounted instead of the bits B.

[0024] In addition, a copy cutter CC is installed on the outer periphery of the cutter head 2. The copy cutter CC has the role of performing overexcavation during curve construction and attitude control of the shield tunneling machine 1. Also, a plurality of stirring rods SB are mounted around the center of the back surface of the cutter head 2. The stirring rod SB is formed of, for example, a columnar protruding member and has the role of stirring and mixing the earth and sand and the additive in the chamber 4 when the cutter head 2 rotates. Note that, for example, a vibration sensor is installed inside this stirring rod SB.

[0025] The equipment body 3 is a main component for driving the shield tunneling machine 1. Equipment for driving the shield tunneling machine 1 and the like are surrounded and protected by a skin plate 5 that constitutes the outer shell of the equipment body 3. The skin plate 5 has a front body plate (front body part) 5a and a rear body plate (rear body part) 5b behind it. The front body plate 5a and the rear body plate 5b are constituted by, for example, cylindrical steel plates, and are engaged by the spherical bearing part at the tip of the rear body plate 5b entering in contact with the inner peripheral surface of the front body plate 5a.

[0026] The rear body plate 5b is composed of a rear body inner cylinder part 5ba located on the side of the front body plate 5a and a rear body outer cylinder part 5bb installed following the rear body inner cylinder part 5ba. The detailed structure of the rear body plate 5b will be described later.

[0027] The hollow space within the skin plate 5 is partitioned into a face side and an in-cabin side by a bulkhead 7 provided inside the front body plate 5a. The aforementioned chamber 4 is provided on the face side of the bulkhead 7 (i.e., between the cutter head 2 and the bulkhead 7). The earth and sand excavated by the cutter head 2 is taken into the chamber 4 through a through-hole (not shown) that penetrates the front and back surfaces of the cutter head 2.

[0028] On the other hand, inside the in-cabin side of the hollow space of the skin plate 5, a cutter drive body 8, a mid-bend jack 9a, a shield jack 9b, a screw conveyor 10, an erector 11, and tail seals 12Ba, 12Bb, etc. are installed. Also, at the tip of the rod 9ba that constitutes the shield jack 9b, a spreader 15 for transmitting the thrust of the shield jack 9b over a wide range of the segment SG (described later) is attached via a block 9bb for aligning the position of the rod 9ba of the shield jack 9b and the position of the segment SG. Although not shown, various devices such as an earth pressure detection unit for detecting the earth pressure inside the chamber 4 and an additive injection unit for injecting the above-mentioned additive (soil-making material) into the chamber 4 are installed in the equipment main body 3 in addition to the above.

[0029] The cutter drive body 8 is a motor (drive source) that rotates the cutter head 2 in the forward and reverse directions, and is installed in a plurality along the circumferential direction of the cutter head 2 at a position near the outer circumference inside the front of the cutter head 2. Here, an outer circumferential support drive method is exemplified as the cutter drive method.

[0030] The mid-bend jack 9a is a device for correcting the propulsion direction and posture of the shield tunneling machine 1, and is installed in a plurality along the circumferential direction of the equipment main body 3 in a state straddling the boundary between the front body plate 5a and the rear body plate 5b so as to connect the front body plate 5a and the rear body plate 5b inside the equipment main body 3. By supplying pressure oil to this mid-bend jack 9a and propelling the shield tunneling machine 1 in a state where the front body plate 5a and the rear body plate 5b are refracted in a predetermined direction and angle, it is possible to control the propulsion direction and posture of the shield tunneling machine 1.

[0031] The shield jack 9b is a device that generates a propulsive force for advancing the shield tunneling machine 1 by taking reaction force from the segment SG installed behind the machine body 3, and is installed in the rear barrel inner cylinder part 5ba that constitutes the rear barrel plate 5b. This shield jack 9b is arranged in a state straddling the boundary between the front barrel plate 5a and the rear barrel plate 5b, and a plurality of them are arranged side by side along the circumferential direction of the machine body 3.

[0032] The screw conveyor 10 is a device for discharging the earth and sand taken into the chamber 4 to the outside of the machine, and is installed so as to penetrate the partition wall 7 from the chamber 4 and continuously extend obliquely upward toward the rear. Here, a ribbon screw conveyor is exemplified.

[0033] The erector 11 is an assembling device that grips the segment SG and turns in the inner circumferential direction of the excavation pit and transfers it to the assembling position in the inner circumferential direction of the excavation pit. It is attached to an intermediate ring body 16 provided along the inner circumferential surface of the rear barrel inner cylinder part 5ba, and is installed in the hollow interior of the rear barrel plate 5b in a rotatable state along the circumferential direction of the excavation pit by a hydraulic motor (not shown) for driving the erector or the like.

[0034] The tail seals 12Ba and 12Bb are provided between the inner circumference of the skin plate 5 and the outer circumference of the segment SG at the rear end of the rear barrel outer cylinder part 5bb that constitutes the rear barrel plate 5b. During the tunneling operation, it is a water stop structure part that prevents groundwater, earth and sand, backfill materials, etc. (hereinafter referred to as groundwater, etc.) from entering the machine interior of the machine body 3 from the outside of the rear end side of the shield tunneling machine 1, and is composed of a springy metal brush and elastic metal plates arranged in front of, behind, and inside the brush so as to sandwich the brush.

[0035] The tail seals 12Ba and 12Bb are installed at two locations along the longitudinal direction of the shield tunneling machine 1 (the central axis direction of the shield tunneling machine 1, the extending direction of the excavation pit) on the inner circumference of the rear end side of the skin plate 5, for example, while being spaced apart from each other. Each of the tail seals 12Ba and 12Bb is installed in a state where a plurality of them are arranged annularly along the inner circumference of the skin plate 5 so as to surround the outer circumference of the segment SG. Further, a seal chamber 12R is formed between these tail seals 12Ba and 12Bb. Note that the number of installed tail seals is not limited to two locations, and for example, they may be installed at three or more locations along the longitudinal direction of the shield tunneling machine 1.

[0036] Further, each of the tail seals 12Ba and 12Bb is installed in a cantilever state on the inner circumference of the skin plate 5. That is, one end side (one end side in the longitudinal direction of the equipment main body 3) of each of the tail seals 12Ba and 12Bb is fixed to the inner circumference of the skin plate 5, and it bends in a state inclined toward the segment SG between the one end side and the other end side (the other end side in the longitudinal direction of the equipment main body 3) of the tail seals 12Ba and 12Bb. Further, the other end side of the tail seals 12Ba and 12Bb comes into contact with the segment SG in a state of being pressed by the spring force of the tail seals 12Ba and 12Bb.

[0037] Further, a sealant supply pipe 14 is installed on the outer circumference of the rear body plate 5b. The sealant supply pipe 14 is a pipe for supplying a sealant such as grease to the seal chamber 12R, and a plurality of them are installed on the outer circumference of the rear body plate 5b. By filling the seal chamber 12R with the sealant through this sealant supply pipe 14, the gap between the inner circumference of the skin plate 5 and the outer circumference of the segment SG is sealed, and together with the tail seals 12Ba and 12Bb, it is possible to prevent groundwater or the like from entering the interior of the shield tunneling machine 1 during the tunneling operation.

[0038] Furthermore, a backfill material supply passage (not shown) is installed on the outer wall of the rear barrel plate 5b. The backfill material supply passage is, for example, a pipe for supplying a backfill material made of a cement-based hardening material or solidifying material into the gap between the excavation pit behind the skin plate 5 and the segment SG. By filling the gap between the excavation pit and the segment SG with the backfill material, ground settlement is prevented, and furthermore, the segment SG and the natural ground are integrated to prevent water leakage from the joint of the segment SG.

[0039] Also, the backfill material supply passage is provided, for example, at two locations sandwiching the top of the skin plate 5. While the sealant supply pipes 14 are provided at a plurality of locations on the outer periphery of the skin plate 5, the backfill material supply passage is provided only near the top of the skin plate 5. This is because the sealant has high viscosity and thus must be evenly supplied to the inner periphery of the skin plate 5 in order to adhere to the outer periphery of the segment SG, whereas the backfill material has low viscosity and thus can flow down to the lower part of the outer periphery of the segment SG by its own weight when supplied near the top of the skin plate 5.

[0040] Note that the formation locations and the number of the sealant supply pipes 14 and the backfill material supply passage are not limited to those described above. For example, more sealant supply pipes 14 may be provided, and the backfill material supply passage may be provided at only one location at the top in the axial direction of the skin plate 5.

[0041] Next, the rear barrel plate 5b of the shield tunneling machine 1 will be described with reference to FIG. 2. FIG. 2 is a main part configuration diagram showing the rear barrel plate 5b as viewed from the side. In FIG. 2, the rear barrel outer cylinder part 5bb has moved to the state where the rear barrel plate 5b is the longest.

[0042] The structure of the rear barrel plate 5b will be described. The rear barrel plate 5b is composed of a rear barrel inner cylinder portion 5ba located on the side of the front barrel plate 5a and a rear barrel outer cylinder portion 5bb installed following the rear barrel inner cylinder portion 5ba, and the rear barrel inner cylinder portion 5ba and the rear barrel outer cylinder portion 5bb partially overlap in the axial direction. Further, the rear barrel outer cylinder portion 5bb is axially movable so as to slide with the rear barrel inner cylinder portion 5ba. Therefore, the overall length of the rear barrel plate 5b expands and contracts by the movement of the rear barrel outer cylinder portion 5bb.

[0043] As shown in FIG. 2, on the inner peripheral surface of the rear barrel outer cylinder portion 5bb, a first fixing member groove portion (first fixing member engaging portion) 21, a second fixing member groove portion (second fixing member engaging portion) 22, and a transmission member groove portion (transmission member engaging portion) 23 are formed in the circumferential direction from the front to the rear. In the present application, the "circumferential direction" refers to the direction within a plane perpendicular to the axial direction of the rear barrel outer cylinder portion 5bb.

[0044] In the first fixing member groove portion 21 and the second fixing member groove portion 22, a fixing member 17 for fixing the rear barrel outer cylinder portion 5bb to the rear barrel inner cylinder portion 5ba so that the rear barrel outer cylinder portion 5bb cannot move is detachably and selectively fitted (engaged) by bolts. That is, as shown in the figure, when the fixing member 17 is fitted into the first fixing member groove portion 21 and fixed to a fixing base 16a provided on an intermediate ring body 16 provided on the rear barrel inner cylinder portion 5ba by bolts, the rear barrel outer cylinder portion 5bb is fixed to the rear barrel inner cylinder portion 5ba at a position where the rear barrel outer cylinder portion 5bb has extended, that is, in a state where the length of the rear barrel plate 5b is relatively long (the first state). Further, when the rear barrel outer cylinder portion 5bb contracts to a length where the position where the first fixing member groove portion 21 was located becomes the position of the second fixing member groove portion 22, and the fixing member 17 is fitted into the second fixing member groove portion 22 and fixed to the fixing base 16a provided on the intermediate ring body 16 provided on the rear barrel inner cylinder portion 5ba by bolts, the rear barrel outer cylinder portion 5bb is fixed to the rear barrel inner cylinder portion 5ba at a position where the rear barrel outer cylinder portion 5bb has contracted, that is, in a state where the length of the rear barrel plate 5b is relatively short (the second state).

[0045] In this embodiment, the rear barrel outer cylinder portion 5bb moves in two stages in this manner, but it may move in three or more stages. In this case, a groove portion for a fixing member is further formed in addition to the first groove portion 21 for a fixing member and the second groove portion 22 for a fixing member. Further, in this embodiment, the fixing member 17 is fixed to a fixing base 16a provided on an intermediate ring body 16 provided on the rear barrel inner cylinder portion 5ba, so that the rear barrel outer cylinder portion 5bb is fixed to the rear barrel inner cylinder portion 5ba. However, the fixing member 17 may be fixed to a fixing base provided other than the intermediate ring body 16 of the rear barrel inner cylinder portion 5ba.

[0046] Further, in the groove portion 23 for a transmission member, a telescopic force transmission member 18 (FIG. 16 etc.) that is fixed to the shield jack 9b and moves the rear barrel outer cylinder portion 5bb in the axial direction by the expansion and contraction of the shield jack 9b is detachably fitted (engaged) by bolts. Therefore, the rear barrel outer cylinder portion 5bb moves to the aforementioned first state or second state by the expansion and contraction of the shield jack 9b.

[0047] In this embodiment, the first engaging portion for a fixing member, the second engaging portion for a fixing member, and the engaging portion for a transmission member are the first groove portion 21 for a fixing member, the second groove portion 22 for a fixing member, and the groove portion 23 for a transmission member that are formed in a concave shape, and the fixing member 17 and the telescopic force transmission member 18 are fitted therein. However, it is not necessary for them to be concave as long as the fixing member 17 and the telescopic force transmission member 18 can be engaged. However, as will be described later, since the spreader 15 moves while sliding on the inner peripheral surface of the rear barrel outer cylinder portion 5bb, if a block for bolt-fastening the fixing member 17 and the telescopic force transmission member 18 is provided, the block will protrude toward the inner diameter side and interfere with the spreader 15, which is not desirable.

[0048] Here, FIG. 3 is a cross-sectional view showing the shield tunneling machine of FIG. 1 along line A of FIG. 2, FIG. 4 is a view showing an extraction of a part of FIG. 3, and FIG. 5 is a cross-sectional view showing the shield tunneling machine of FIG. 1 along line B of FIG. 2.

[0049] As shown in Fig. 3, an intermediate ring body 16 is annularly provided along the inner peripheral surface of the rear barrel inner cylinder part 5ba. A plurality of (eight in this embodiment) shield jacks 9b are installed in the circumferential direction at regular intervals on the intermediate ring body 16. Further, between the shield jacks 9b, a fixing member 17 for fixing the rear barrel outer cylinder part 5bb to the rear barrel inner cylinder part 5ba is positioned in a state of being fitted into a first fixing member groove part 21 formed in the rear barrel outer cylinder part 5bb.

[0050] Furthermore, rolling stoppers (restricting means) 19 for restricting the circumferential displacement of the rear barrel outer cylinder part 5bb with respect to the rear barrel inner cylinder part 5ba are provided between the shield jacks 9b and the fixing member 17 at two locations each in the vertical direction. The rolling stopper 19 prevents rolling (circumferential displacement of the rear barrel outer cylinder part 5bb) that is likely to occur during curve construction described later.

[0051] As shown in Fig. 4 and Fig. 8 described later, the rolling stopper 19 includes a fitting groove 19a extending along the axial direction of the rear barrel outer cylinder part 5bb, and a fitting member 19b provided on the rear barrel inner cylinder part 5ba and fitted into the fitting groove 19a and movable along the fitting groove 19a. The fitting groove 19a is formed in a space sandwiched between a pair of plate-like bodies 20 installed in parallel on the inner peripheral surface of the rear barrel outer cylinder part 5bb. In this embodiment, the fitting groove 19a is formed in the rear barrel outer cylinder part 5bb and the fitting member 19b is provided on the rear barrel inner cylinder part 5ba. Conversely, the fitting groove 19a may be formed in the rear barrel inner cylinder part 5ba and the fitting member 19b may be provided on the rear barrel outer cylinder part 5bb.

[0052] As shown in Fig. 5, the spreader 15 attached to the tip of the shield jack 9b has a pressing surface 15f (a surface facing the tip surface of the segment SG and pressing the segment SG) formed in a substantially arc shape along the circumferential direction of the rear barrel outer cylinder part 5bb and longer than the tip surface of the rod 9ba of the shield jack 9b or the tip surface of the block 9bb in a front view. With such a shape, the thrust of the shield jack 9b is diffused and transmitted to the segment SG.

[0053] In FIG. 5, at both ends on the inner peripheral surface side of the rear barrel outer cylinder portion 5bb in the spreader 15, there are formed leg portions (restricting protrusions) 15a that restrict the spreader 15 from displacing radially outward of the rear barrel outer cylinder portion 5bb.

[0054] The spreader 15 is attached to the tip of a block 9bb for aligning the position of the rod 9ba of the shield jack 9b and the position of the segment SG. As shown in FIG. 2, the block 9bb is located radially outward of the rear barrel outer cylinder portion 5bb at the portion that presses the segment SG rather than the portion pressed by the rod 9ba of the shield jack 9b (that is, the portion where the spreader 15 is attached). Therefore, when the segment SG is pressed by the shield jack 9b, the spreader 15 tends to displace radially outward of the rear barrel outer cylinder portion 5bb. At this time, if the leg portion 15a that restricts the displacement radially outward of the rear barrel outer cylinder portion 5bb is not formed, the displacement of the spreader 15 radially outward of the rear barrel outer cylinder portion 5bb will be allowed, and when the shield jack 9b is extended and the shield tunneling machine 1 tunnels, a force that expands radially outward will act on the annular segment SG that is being pressed by the spreader 15. On the other hand, when the leg portion 15a is formed as in the present embodiment, no force that expands radially outward acts on the segment SG.

[0055] In the present embodiment, the displacement of the spreader 15 radially outward of the rear barrel outer cylinder portion 5bb is restricted by the two leg portions 15a that are protrusions formed at both ends on the inner peripheral surface side of the rear barrel outer cylinder portion 5bb in the spreader 15, but the number of protrusions may be one or three or more.

[0056] Note that instead of forming protrusions such as the leg portion 15a on the spreader 15 side, it is also conceivable to form protrusions for restricting the displacement of the spreader 15 on the inner peripheral surface of the rear barrel outer cylinder portion 5bb. However, in the shield tunneling machine 1 of the present embodiment, as described above, the rear barrel outer cylinder portion 5bb is configured to move in the axial direction so as to slide with the rear barrel inner cylinder portion 5ba. Therefore, providing protrusions on the inner peripheral surface of the rear barrel outer cylinder portion 5bb that contacts the rear barrel inner cylinder portion 5ba would hinder the movement. Thus, it is not desirable to provide such protrusions.

[0057] Further, on the inner peripheral surface of the rear barrel outer cylinder portion 5bb, the above-described first fixing member groove portion 21, second fixing member groove portion 22, and transmission member groove portion 23 are formed. Therefore, when the spreader 15 reaches the positions of the groove portions 22 and 23, the leg portion 15a of the spreader 15 fits into the groove portions 22 and 23. And in order to prevent the fitting, it is necessary to make the portions of the groove portions 22 and 23 through which the leg portion 15a of the spreader 15 passes flush with the inner peripheral surface of the rear barrel outer cylinder portion 5bb. A member (flat plate 24) for making the fixing member groove portion 22 and the transmission member groove portion 23 through which the leg portion 15a passes flush with the inner peripheral surface of the rear barrel outer cylinder portion 5bb will be described later.

[0058] Here, FIG. 6 is a plan view showing the spreader and the surrounding mechanism in the present embodiment, and FIG. 7 is a plan view showing the spreader and the surrounding mechanism as a comparative example.

[0059] As shown in FIG. 6, in the spreader 15 of the present embodiment, a concave portion 15b for avoiding interference with the fixing member 17 is formed on the surface opposite to the pressing surface 15f when the shield jack 9b is maximally contracted. If the concave portion 15b is not formed, as shown in FIG. 7, in order to prevent the spreader 15 from interfering with the fixing member 17 when the shield jack 9b is maximally contracted, the retraction position of the spreader 15 cannot be made further forward. On the other hand, when the concave portion 15b is formed as in the present embodiment, even if the retraction position of the spreader 15 when the shield jack 9b is maximally contracted is more forward than the case shown in FIG. 7, the spreader 15 does not interfere with the fixing member 17. As a result, it becomes possible to maximize the retraction amount of the rear body outer cylinder portion 5bb with respect to the rear body inner cylinder portion 5ba when the shield jack 9b contracts, and the length of the rear body plate 5b in the second state described above can be made shorter.

[0060] FIG. 8 is a plan view showing a half circumference of the inner peripheral surface of the rear body outer cylinder portion in a shield tunneling machine according to an embodiment of the present invention developed, FIG. 9 is a plan view showing the axial direction of the rear body outer cylinder portion developed along line C in FIG. 5, FIG. 10 is a plan view showing the axial direction of the rear body outer cylinder portion developed along line D in FIG. 5, and FIG. 11 is a plan view showing the axial direction of the rear body outer cylinder portion developed along line E in FIG. 5.

[0061] In FIG. 8, in the rear body outer cylinder portion 5bb of the shield tunneling machine 1, the above-described first fixing member groove portion 21, second fixing member groove portion 22, and transmission member groove portion 23 are formed. As shown in the drawing, these fixing member groove portions 21, 22 and transmission member groove portion 23 are annular grooves formed over the entire circumference in the circumferential direction of the inner peripheral surface of the rear body outer cylinder portion 5bb. To specifically explain the formation process of these fixing member groove portions 21, 22 and transmission member groove portion 23, two half-circumference rear body outer cylinder portions 5bb in a flat plate shape are produced, each is bent into a semi-circular shape, and the ends are joined by welding to obtain a cylindrical rear body outer cylinder portion 5bb. Then, the inner circumference of the rear body outer cylinder portion 5bb is machined with a lathe to form the fixing member groove portions 21, 22 and transmission member groove portion 23 which are annular grooves.

[0062] Note that the first fixing member groove portion 21, the second fixing member groove portion 22, and the transmission member groove portion 23 do not necessarily need to be formed in an annular shape over the entire circumference in the circumferential direction of the inner peripheral surface of the rear cylinder outer cylinder portion 5bb as in the present embodiment, and may be formed spotwise at the locations where the fixing member 17 and the expansion / contraction force transmission member 18 are fixed.

[0063] However, when the first fixing member groove portion 21, the second fixing member groove portion 22, and the transmission member groove portion 23 are formed spotwise, it takes time because they must be formed only at discontinuous specific locations, and thermal stress is applied to the metal rear cylinder outer cylinder portion 5bb, resulting in distortion. However, if they are formed in an annular shape as in the present embodiment, such problems do not occur.

[0064] Now, as shown in FIG. 9, in the axial direction of the rear cylinder outer cylinder portion 5bb along line C in FIG. 5, holes 21a and 22a are formed for fitting the above-described fixing member 17 into the first fixing member groove portion 21 or the second fixing member groove portion 22 and fixing it to the rear cylinder outer cylinder portion 5bb with bolts.

[0065] Further, as shown in FIG. 10, in the axial direction of the rear cylinder outer cylinder portion 5bb along line D in FIG. 5, a hole 23a is formed for fitting the expansion / contraction force transmission member 18 into the transmission member groove portion 23 and fixing it to the rear cylinder outer cylinder portion 5bb with bolts.

[0066] Furthermore, as shown in FIG. 11, in the axial direction of the rear body outer cylinder portion 5bb along line E in FIG. 5, a flat plate (smoothing member) 24 is provided flush with the second fixing member groove portion 22, the transmission member groove portion 23, and the inner peripheral surface of the rear body outer cylinder portion 5bb to prevent the spreader 15 from fitting in. That is, as described above, since the leg portion 15a of the spreader 15 moves along the inner peripheral surface of the rear body outer cylinder portion 5bb, without any measures, the leg portion 15a of the spreader 15 may fit into the second fixing member groove portion 22 and the transmission member groove portion 23 and cannot move smoothly. Therefore, by installing the flat plate 24 at the location where the leg portion 15a of the spreader 15 passes through the second fixing member groove portion 22 and the transmission member groove portion 23, the leg portion 15a is prevented from fitting in. In the case where the leg portion 15a is not provided, the flat plate 24 is installed at the entire passing location of the spreader 15 in the second fixing member groove portion 22 and the transmission member groove portion 23.

[0067] In the present embodiment, since the range of the fixing member 17 when it is fitted and fixed in the second fixing member groove portion 22 overlaps with the range through which the spreader 15 (specifically, the leg portion 15a of the spreader 15 in contact with the inner peripheral surface of the rear body outer cylinder portion 5bb) passes (that is, the portion of the flat plate 24 installed in the second fixing member groove portion 22), when the fixing member 17 is fitted into the second fixing member groove portion 22, it interferes with the flat plate 24 installed in the second fixing member groove portion 22, so it is necessary to remove the flat plate 24. Therefore, as shown in FIG. 11, the flat plate 24 in the second fixing member groove portion 22 is detachably bolted. However, if the position when the fixing member 17 is fitted into the second fixing member groove portion 22 does not overlap with the location where the spreader 15 passes, of course, the flat plate 24 installed in the second fixing member groove portion 22 may also be fixed to the rear body outer cylinder portion 5bb.

[0068] In addition, in the present embodiment, the range of the expansion / contraction force transmission member 18 when it is fitted and fixed in the groove portion 23 for the transmission member does not overlap with the range through which the spreader 15 (specifically, the leg portion 15a of the spreader 15 in contact with the inner peripheral surface of the rear cylinder outer cylinder portion 5bb) passes (that is, the portion of the flat plate 24 installed in the groove portion 23 for the transmission member). Therefore, even when the expansion / contraction force transmission member 18 is fitted into the groove portion 23 for the transmission member, it does not interfere with the flat plate 24 installed in the groove portion 23 for the transmission member, so there is no need to remove the flat plate 24. On the other hand, in order to prevent damage to the segment SG, it is better to cover the groove portion 23 for the transmission member. Therefore, as shown in FIG. 11, the flat plate 24 of the groove portion 23 for the transmission member is fixed to the rear cylinder outer cylinder portion 5bb. However, when the range when the expansion / contraction force transmission member 18 is fitted into the groove portion 23 for the transmission member overlaps with the range through which the spreader 15 passes, the flat plate 24 installed in the groove portion 23 for the transmission member is made detachable by bolting.

[0069] Note that it is desirable to fix the flat plate 24 to the rear cylinder outer cylinder portion 5bb by stagger welding (intermittent fillet welding in which welded portions and non-welded portions exist alternately) to reduce the heat input during welding.

[0070] (Example 1)

[0071] Next, as Example 1, the expansion / contraction operation of the rear body plate 5b in the shield tunneling machine 1 having the above configuration will be described with reference to FIGS. 12 to 26. Here, FIGS. 12 to 19 are diagrams continuously showing the contraction operation of the rear body plate of the shield tunneling machine in FIG. 1, and FIGS. 20 to 26 are diagrams continuously showing the extension operation of the rear body plate of the shield tunneling machine in FIG. 1. In these drawings, (a) is a conceptual diagram of the rear body plate seen from the plane, and (b) is an explanatory diagram of the rear body plate seen from the side. Also, in (a), a pair of two adjacent shield jacks out of the eight shield jacks installed in the present embodiment are shown, and the other pairs of shield jacks operate in the same manner.

[0072] In the shield tunneling machine 1 that performs the telescoping operation of the rear body plate 5b, in FIG. 2, when in the first state, the dimension of the outer cylinder portion 5bb of the rear body is such that the length (effective length: FL) of the portion that does not overlap with the inner cylinder portion 5ba of the rear body is 1970 mm, the length (L1) other than the tail seals 12Ba and 12Bb within the effective length is 1490 mm, the length (L2) of the tail seals 12Ba and 12Bb is 480 mm, and the distance (L3) between the first fixing member groove portion 21 and the second fixing member groove portion 22 is 300 mm. And since the movable length of the outer cylinder portion 5bb of the rear body corresponds to the distance (L3) between the first fixing member groove portion 21 and the second fixing member groove portion 22, it is 300 mm. However, these dimensions are examples, and the present invention is not limited to these dimensions.

[0073] First, the contraction operation (the operation in which the outer cylinder portion 5bb of the rear body moves from the first state to the second state) of the rear body plate 5b of the shield tunneling machine 1 will be described. Note that the rear body plate 5b is mainly contracted when shifting from straight tunneling to curved tunneling.

[0074] As shown in FIG. 12, in straight tunneling, the outer cylinder portion 5bb of the rear body is set in the first state and the length of the rear body plate 5b is made long. For example, segments SG with a width of 900 mm are continuously installed in the excavation pit. In this state, the fixing member 17 is fitted into the first fixing member groove portion 21 and fixed to the fixing base 16a, and a flat plate 24 is installed in the second fixing member groove portion 22. Note that the segment SG is a tunnel lining member for forming a tunnel by being assembled annularly within the shield tunneling machine 1.

[0075] In order to shift to curved tunneling from here and contract the rear body plate 5b by setting the outer cylinder portion 5bb of the rear body in the second state to shorten the length, first, as shown in FIG. 13, the shield jack 9b is stroked by a predetermined length (the length at which the telescopic force transmission member 18 can be fitted into the transmission member groove portion 23) to advance the shield tunneling machine 1 and form a space sufficient for assembling a segment SG with a width of, for example, 300 mm for curved tunneling.

[0076] Next, remove the flat plate 24 installed in the groove 22 for the second fixing member, and as shown in FIG. 14, remove the fixing member 17 fixed to the fixing base 16a and relocate it from the groove 21 for the first fixing member to the groove 22 for the second fixing member.

[0077] Next, as shown in FIG. 15, with some of the shield jacks 9b pressed against the segment SG (that is, in a state where the anti-backring measures to prevent the backward movement of the shield tunneling machine 1 are taken), pull the other shield jacks 9b by a predetermined length. The length by which the shield jacks 9b are pulled is such that the telescopic force transmission member 18 can be fitted into the groove 23 for the transmission member and fixed to the tip of the shield jacks 9b, and further, a spacer 18a (FIG. 20, etc.) can be attached to the tip thereof. In this embodiment, the anti-backring measures are taken with a total of four shield jacks 9b, two upper ones and two lower ones. However, it goes without saying that the anti-backring measures may be taken with shield jacks 9b other than these.

[0078] Next, as shown in FIG. 16, fit the telescopic force transmission member 18 into the groove 23 for the transmission member and fix it to the rear body outer cylinder portion 5bb with bolts, and fix it to the tip of the shield jacks 9b (specifically, to the spreader 15 provided on the shield jacks 9b) with tension bolts.

[0079] Next, as shown in FIG. 17, pull the shield jacks 9b until the fixing member 17 fitted in the groove 22 for the second fixing member hits the fixing base 16a. As a result, the rear body outer cylinder portion 5bb moves forward, and it becomes the second state in which the length of the rear body plate 5b is relatively shortened. Here, since the distance between the groove 21 for the first fixing member and the groove 22 for the second fixing member (the length of L3 in FIG. 2) is 300 mm, the length of the rear body plate 5b is shortened by 300 mm.

[0080] If the rear barrel outer cylinder part 5bb has moved forward in this way, the fixing member 17 is fixed to the fixing base 16a with bolts, and as shown in Fig. 18, the telescopic force transmission member 18 is removed and the shield jack 9b is further pulled. As a result, the transition to the state during curve construction, in which the followability to the curve is good and the curve construction can be carried out smoothly, is completed.

[0081] After that, while performing curve excavation with the shield tunneling machine 1, as shown in Fig. 19, segments SG for curve construction (for example, segments SG with a width of 300 mm) are installed.

[0082] Next, the extension operation of the rear barrel plate 5b of the shield tunneling machine 1 (the operation in which the rear barrel outer cylinder part 5bb moves from the second state to the first state) will be described. Note that the rear barrel plate 5b is mainly extended when transitioning from curve construction to straight-line construction.

[0083] If the curve construction is completed with the rear barrel outer cylinder part 5bb in the second state and the rear barrel plate 5b shortened, as shown in Fig. 20, some of the shield jacks 9b are pressed against the segment SG, and the telescopic force transmission member 18 is fitted into the transmission member groove part 23 on the extension line of the other shield jacks 9b and fixed to the rear barrel outer cylinder part 5bb with bolts. Further, a spacer 18a is attached to the segment SG side of the telescopic force transmission member 18. Note that, as shown in the figure, since a space is required to attach the spacer 18a to the telescopic force transmission member 18, a slight gap is formed between the spacer 18a attached to the telescopic force transmission member 18 and the segment SG.

[0084] Next, as shown in Fig. 21, the shield jack 9b is extended to press the spreader 15 against the telescopic force transmission member 18, and the fixing member 17 fitted in the second fixing member groove part 22 is removed. As a result, the fastening between the rear barrel outer cylinder part 5bb and the fixing base 16a provided on the intermediate ring body 16 is released, and the rear barrel outer cylinder part 5bb becomes movable in the axial direction.

[0085] Next, as shown in Fig. 22, extend the shield jack 9b to press the spacer 18a against the segment SG and move the rear cylinder inner cylinder part 5ba forward to a position where the fixing member 17 can be fitted into the first fixing member groove part 21 and fixed to the fixing base 16a. As a result, the rear cylinder inner cylinder part 5ba moves forward, and it becomes the first state where the length of the rear cylinder plate 5b is relatively long. Here, since the distance between the first fixing member groove part 21 and the second fixing member groove part 22 (the length of L3 in Fig. 2) is 300 mm, the length of the rear cylinder plate 5b becomes 300 mm longer.

[0086] Note that, as described above, since a slight gap is formed between the spacer 18a and the segment SG, when the shield jack 9b extends and the spacer 18a is pressed against the segment SG via the expansion and contraction force transmission member 18, the rear cylinder outer cylinder part 5bb moves backward by the amount of the gap. Then, the tail seals 12Ba and 12Bb move backward by moving in the direction opposite to their original movement (forward movement) with respect to the segment SG. However, since the amount of movement is only slight corresponding to the aforementioned gap, problems such as deformation of the shapes of the tail seals 12Ba and 12Bb do not occur.

[0087] Next, as shown in Fig. 23, fit the fixing member 17 into the first fixing member groove part 21 and fix it to the fixing base 16a, and also fix it to the rear cylinder outer cylinder part 5bb with bolts. Also, install the flat plate 24 in the second fixing member groove part 22.

[0088] Next, as shown in Fig. 24, bring the shield jack 9b to a state where the expansion and contraction force transmission member 18 and the spacer 18a are not attached and press it against the segment SG. Then, slightly pull the shield jack 9b to which the expansion and contraction force transmission member 18 and the spacer 18a are attached to form a gap between the spacer 18a and the segment SG, and remove the expansion and contraction force transmission member 18 and the spacer 18a.

[0089] Next, as shown in Fig. 25, extend the shield jack 9b to move the shield tunneling machine 1 forward, forming a space sufficient to assemble the segments SG for straight tunneling.

[0090] Next, as shown in Fig. 26, when the shield jack 9b is pulled, the transition to the straight tunneling state in which straight tunneling can be performed smoothly is completed.

[0091] Thereafter, while performing straight excavation with the shield tunneling machine 1, the segments SG for straight tunneling (for example, segments SG with a width of 900 mm) are installed.

[0092] Thus, according to the shield tunneling machine 1 of this embodiment, the outer rear barrel portion 5bb constituting the rear barrel plate 5b is movable in the axial direction so as to slide with the inner rear barrel portion 5ba, and the entire length of the rear barrel plate 5b expands and contracts due to the movement of the outer rear barrel portion 5bb. Therefore, by moving the outer rear barrel portion 5bb from the first state to the second state, smooth curved tunneling can be performed. As a result, not only is the followability to the curve improved, but overexcavation does not increase.

[0093] (Embodiment 2)

[0094] Next, as Embodiment 2, the replacement of the tail seal 12Ba in the shield tunneling machine 1 having the above configuration will be described with reference to Figs. 27 to 41. Here, Figs. 27 to 41 are diagrams continuously showing the replacement procedure of the tail seal of the shield tunneling machine of Embodiment 2. In these drawings, (a) is a conceptual diagram of the rear barrel plate seen from the plane, and (b) is an explanatory diagram of the rear barrel plate seen from the side. Also, in (a), a pair of two adjacent shield jacks out of the eight shield jacks installed in this embodiment are shown, and the other pairs of shield jacks operate in the same manner.

[0095] In the shield tunneling machine 1 for replacing the tail seal 12Ba, in FIG. 2, when in the first state, the dimension of the rear body outer cylinder part 5bb is such that the length (effective length: FL) of the part that does not overlap with the rear body inner cylinder part 5ba is 1610 mm, the length (L1) other than the tail seals 12Ba and 12Bb within the effective length is 1130 mm, the length (L2) of the tail seals 12Ba and 12Bb is 480 mm, and the distance (L3) between the first fixing member groove part 21 and the second fixing member groove part 22 is 350 mm. And since the movable length of the rear body outer cylinder part 5bb corresponds to the distance (L3) between the first fixing member groove part 21 and the second fixing member groove part 22, it is 350 mm. However, these dimensions are just examples, and the present invention is not limited to these dimensions.

[0096] Also, the tail seal to be replaced is the tail seal 12Ba located in front among the tail seals 12Ba and 12Bb provided at two places, front and rear. This is because the tail seal 12Bb located at the rear directly receives the pressure of groundwater and earth and sand, so this tail seal 12Bb cannot be removed for replacement.

[0097] And due to the respective dimensions of the rear body outer cylinder part 5bb described above, when the rear body outer cylinder part 5bb is in the second state (the position where the length of the rear body plate 5b becomes relatively short), the tail seal 12Ba located in front comes off from the segment SG and is exposed inside the machine.

[0098] Now, in the replacement of the tail seal 12Ba, as shown in FIG. 27, the rear body outer cylinder part 5bb is set in the first state. In this first state, the fixing member 17 is fitted into the first fixing member groove part 21 and fixed to the fixing base 16a, and a flat plate 24 is installed in the second fixing member groove part 22.

[0099] Next, as shown in FIG. 28, the shield jack 9b is stroked by a predetermined length (the length at which the expansion and contraction force transmission member 18 can be fitted into the transmission member groove part 23) to advance the shield tunneling machine 1.

[0100] Next, after removing the flat plate 24 installed in the groove 22 for the second fixing member, the fixing member 17 is removed from the rear body inner cylinder portion 5ba, and as shown in FIG. 29, the removed fixing member 17 is relocated to the groove 22 for the second fixing member.

[0101] Next, as shown in FIG. 30, with some of the shield jacks 9b (the lower shield jack 9b in the case shown in FIG. 30(a)) pressed against the segment SG (that is, in a state where anti-backring measures are taken), the other shield jack 9b (the upper shield jack 9b in the case shown in FIG. 30(a)) is pulled by a predetermined length and pressed against the segment SG via the anti-backring member 25.

[0102] Next, as shown in FIG. 31, the shield jack 9b (the lower shield jack 9b in the case shown in FIG. 31(a)) pressed against the segment SG is pulled by a predetermined length, the telescopic force transmission member 18 is fitted into the groove 23 for the transmission member and fixed to the rear body outer cylinder portion 5bb with bolts, and is fixed to the tip of the shield jack 9b (specifically, to the spreader 15 provided on the shield jack 9b) with a tension bolt.

[0103] Next, as shown in FIG. 32, the shield jack 9b to which the telescopic force transmission member 18 is fixed is pulled by a predetermined length to pull in the rear body outer cylinder portion 5bb. Specifically, the shield jack 9b is pulled until the fixing member 17 fitted in the groove 22 for the second fixing member hits the fixing base 16a. As a result, the rear body outer cylinder portion 5bb moves forward, and the rear body plate 5b becomes relatively shorter in the second state. Here, since the distance between the groove 21 for the first fixing member and the groove 22 for the second fixing member (the length of L3 in FIG. 2) is 350 mm, the length of the rear body plate 5b is shortened by 350 mm. And as the rear body outer cylinder portion 5bb moves forward, as shown in the figure, the tail seal 12Ba comes off from the segment SG and is exposed inside the machine. The fixing member 17 is fixed to the fixing base 16a with bolts.

[0104] Next, as shown in FIG. 33, replace the tail seal 12Ba in the portion that does not interfere with the anti-backring member 25 with a new tail seal 12Ba. In FIG. 33, the tail seal 12Ba in the portion to be replaced is indicated by a mesh line.

[0105] If a part of the tail seal 12Ba is replaced in this way, as shown in FIG. 34, remove the expansion force transmission member 18 from the groove portion 23 for the transmission member, interpose the anti-backring member 25 between the removed shield jack 9b and the segment SG, and extend the shield jack 9b to press the anti-backring member 25 against the segment SG.

[0106] Next, as shown in FIG. 35, remove the anti-backring member 25 located in the portion where the tail seal 12Ba has not been replaced, fit the expansion force transmission member 18 into the groove portion 23 for the transmission member and fix it to the rear body outer cylinder portion 5bb with bolts, and also fix it to the tip of the shield jack 9b (specifically, to the spreader 15 provided on the shield jack 9b) with a tension bolt. However, since the anti-backring member 25 is interposed between the shield jack 9b and the segment SG in the portion where the tail seal 12Ba has been replaced, and the fixing member 17 is fixed to the fixing base 16a, the attachment of the expansion force transmission member 18 may be omitted.

[0107] If the position of the anti-backring member 25 is swapped in this way, as shown in FIG. 36, replace the tail seal 12Ba in the portion that no longer interferes with the newly installed anti-backring member 25 (that is, the remaining portion of the tail seal 12Ba) with a new tail seal 12Ba. As a result, the entire tail seal 12Ba will be replaced.

[0108] Then, as shown in FIG. 37, the segment SG is installed after removing the back-ring prevention member 25. As a result, the new tail seal 12Ba, which was in an exposed state inside the machine, is radially outwardly expanded by the segment SG and positioned on the outer periphery of the installed segment SG. Thereby, the replacement of the tail seal 12Ba in the shield tunneling machine 1 is completed. Note that, in the state where the segment SG is installed, back-ring prevention is performed by the shield jack 9b to which the expansion / contraction force transmission member 18 is not fixed.

[0109] If the replacement of the tail seal 12Ba is thus completed and the segment SG is installed, as shown in FIG. 38, a spacer 18a is attached to the segment SG side of the expansion / contraction force transmission member 18, and further, the fixing member 17 fitted in the second fixing member groove portion 22 is removed. Thereby, the rear body outer cylinder portion 5bb is released from the fastening with the fixed base 16a and becomes movable in the axial direction. Note that, as shown in the drawing, since a space is required for attaching the spacer 18a to the expansion / contraction force transmission member 18, a slight gap is formed between the spacer 18a attached to the expansion / contraction force transmission member 18 and the segment SG.

[0110] Next, as shown in FIG. 39, the shield jack 9b is extended to move the rear body inner cylinder portion 5ba forward, the fixing member 17 is fitted into the first fixing member groove portion 21 and fixed to the fixed base 16a, and is also fixed to the rear body outer cylinder portion 5bb with bolts. Further, a flat plate 24 is installed in the second fixing member groove portion 22. Thereby, the rear body inner cylinder portion 5ba moves forward, and the first state is reached where the length of the rear body plate 5b becomes relatively long. Here, since the distance between the first fixing member groove portion 21 and the second fixing member groove portion 22 (the length of L3 in FIG. 2) is 350 mm, the length of the rear body plate 5b becomes 350 mm longer.

[0111] Note that, as described above, since a slight gap is formed between the spacer 18a and the segment SG, when the shield jack 9b extends and the spacer 18a is pressed against the segment SG via the telescopic force transmission member 18, the rear body outer cylinder portion 5bb moves backward by the amount of the gap. Then, the tail seals 12Ba and 12Bb move backward by moving in a direction opposite to their original movement (forward movement) with respect to the segment SG. However, since the amount of movement is slight corresponding to the aforementioned gap, problems such as deformation of the shapes of the tail seals 12Ba and 12Bb do not occur.

[0112] Next, as shown in FIG. 40, with the shield jack 9b to which the telescopic force transmission member 18 and the spacer 18a are not attached pressed against the segment SG, the shield jack 9b to which the telescopic force transmission member 18 and the spacer 18a are attached is slightly pulled to form a gap between the spacer 18a and the segment SG, and the telescopic force transmission member 18 and the spacer 18a are removed.

[0113] Next, as shown in FIG. 41, the shield jack 9b is pulled to install the segment SG.

[0114] Thus, according to the shield tunneling machine 1 of the present embodiment, since the rear body outer cylinder portion 5bb constituting the rear body plate 5b is axially movable so as to slide with the rear body inner cylinder portion 5ba, when the rear body outer cylinder portion 5bb moves from the first position to the second position, the tail seal 12Ba comes off from the segment SG and is exposed inside the machine. Therefore, it becomes possible to perform the replacement work of the tail seal 12Ba from inside the shield machine. Thereby, troubles caused by deterioration or damage of the tail seal 12Ba can be prevented in advance.

[0115] As described above, the invention made by the present inventor has been specifically described based on the embodiments. However, the embodiments disclosed in this specification are illustrative in all respects and are not limited to the disclosed technology. That is, the technical scope of the present invention should not be construed restrictively based on the description in the above embodiments, but should be construed according to the description in the claims. All changes that do not deviate from the technical scope described in the claims and the gist of the claims, including technologies equivalent to the technologies described in the claims, are included.

Industrial Applicability

[0116] In the above description, the case where the present invention is applied to an earth pressure shield tunneling machine has been described. However, the present invention is not limited thereto. For example, it can also be applied to other shield tunneling machines, such as a slurry shield tunneling machine having a mechanism for stabilizing the face by applying a predetermined pressure to the slurry in the chamber and transporting the excavated soil and sand by circulating the slurry.

Explanation of Signs

[0117] 1 Shield tunneling machine 2 Cutter head 3 Equipment body 5 Skin plate 5a Front body plate (front body part) 5b Rear body plate (rear body part) 5ba Inner cylinder part of the rear body 5bb Outer cylinder part of the rear body 9a Middle folding jack 9b Shield jack 9ba Rod 9bb Block 12Ba, 12Bb Tail seal 12R Seal chamber 15 Spreader 15a Leg (restricting projection) 15b Concave part 15f Pressing surface 16 Intermediate ring body 16a Fixed base 17 Fixing member 18 Telescopic force transmission member 18a spacer 19 rolling stopper (restricting means) 19a fitting groove 19b fitting member 20 plate-like body 21 groove portion for first fixing member (engagement portion for first fixing member) 22 groove portion for second fixing member (engagement portion for second fixing member) 23 groove portion for transmission member (engagement portion for transmission member) 21a, 22a, 23a holes 24 flat plate (smoothing member) 25 back buckling prevention member SG segment

Claims

【Claim 1】 a front body portion provided with a cutter head, a rear body inner cylinder portion provided with a plurality of shield jacks positioned on the front body side and having spreaders attached to their tips, and a rear body portion having a rear body outer cylinder portion that follows the rear body inner cylinder portion, partially overlaps with the rear body inner cylinder portion, and is axially movable, comprising: on the rear body outer cylinder portion, a first engaging portion for a fixing member, a second engaging portion for a fixing member, and an engaging portion for a transmission member, which are each formed in a concave shape in the circumferential direction from the front to the rear on the inner circumferential surface; fixed to a fixing base provided on an intermediate ring body provided annularly along the inner circumferential surface of the rear body inner cylinder portion, detachably engaging with the first engaging portion for a fixing member to fix the rear body outer cylinder portion to the rear body inner cylinder portion in a first state where the length of the rear body portion is relatively long, and detachably engaging with the second engaging portion for a fixing member to fix the rear body outer cylinder portion to the rear body inner cylinder portion in a second state where the length of the rear body portion is relatively short; a fixing member; an expansion / contraction force transmission member that detachably engages with the engaging portion for a transmission member to fix the spreader of the shield jack to the rear body outer cylinder portion is provided, a concave portion is formed on the surface opposite to the pressing surface of the spreader to avoid interference with the fixing member when the shield jack is maximally contracted. A shield tunneling machine characterized by the above.

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