JP7693263B2 - Shield tunneling machine - Google Patents

Description

The present invention relates to a shield tunneling machine.

Shield tunneling machines are known as devices used to excavate the ground to create shield tunnels for tunnels and subways.

This shield excavator has a rotatable cutter head installed at the leading edge of the skin plate in the direction of travel, and multiple bits are arranged circumferentially and radially on the cutter head. The cutter head is pressed against the excavation face (face) and rotated as it moves forward, excavating the ground in a circular shape. Inside the shield excavator, cylindrically assembled segments are pushed out behind the skin plate as the shield excavator advances.

When constructing curved sections of a shield tunnel using such a shield machine, the shield machine is bent using a bending jack to bend the machine to fit the curve.

At the rear end of the skin plate that constitutes the shield tunneling machine, a tail seal is provided to seal between the skin plate and the segment during shield construction to prevent groundwater from entering the shield tunneling machine. This tail seal is pressed against the outer peripheral surface of the segment and moves as the shield tunneling machine excavates. In addition, shield tunnels are becoming longer in length (generally, 1.5 km or more is called long distance, and 3.0 km or more is called ultra-long distance). Various problems occur, such as malfunctions of the segments and abnormal increases in thrust, due to deterioration or damage to the tail seal caused by the longer distance of such shield tunnels (deformation of the seal material itself, loss or deformation of wire brushes, etc.). Therefore, in order to prevent such problems from occurring, it is necessary to replace the tail seal during excavation.

The construction of curved lines in a shield tunneling machine is described, for example, in Patent Document 1, which discloses a technique for constructing sharp curves by dividing the shield body into two parts, front and rear, and connecting them so that they can be freely bent, and then inscribing the skin plates on the inner side of the bent front and rear bodies with the inner circumference of the tunnel wall, and moving the outer side of the bent front end of the front body and the outer side of the bent rear end of the rear body along the outer circumference of the tunnel wall.

Regarding the replacement of tail seals in shield tunneling machines, for example, Patent Document 2 discloses a technology in which the skin plate on the rear body is doubled, and the inner skin plate is left underground while the machine excavates and advances, exposing the inner surface of the outer skin plate that was previously covered by the inner skin plate to the inside of the tunnel, and a new tail seal is then attached to this inner surface from inside the tunnel.

Japanese Patent Application Publication No. 5-106390 JP 2005-133424 A

Now, in constructing the shield tunnel mentioned above, depending on the construction location, it may be necessary to excavate a sharp curve. In this case, depending on the maximum bending angle of the shield tunneling machine, it may be difficult to follow the required sharp curve or there may be a large amount of overexcavation.

In addition, to prevent problems caused by deterioration or damage to the tail seal, it will be necessary to replace the tail seal from inside the shield machine while excavation is in progress.

The present invention was made against the above technical background, and aims to provide a technology that allows smooth curved construction using a shield tunneling machine.

The present invention was made in light of the above technical background, and aims to provide a technology that allows replacement of the tail seal of a shield tunneling machine to be performed from inside the shield machine.

In order to solve the above problems, the shield tunneling machine of the present invention described in claim 1 comprises a front body section on which a cutter head is installed, a rear body inner tubular section on which a plurality of shield jacks with spreaders attached to their tips are installed and which are located on the front body section side, and a rear body outer tubular section which is installed subsequent to the rear body inner tubular section and partially overlaps with the rear body inner tubular section and is movable in the axial direction, the rear body outer tubular section having a first fixing member engaging portion, a second fixing member engaging portion and a transmission member engaging portion which are each formed in a circumferentially concave shape from the front to the rear on the inner circumferential surface of the rear body outer tubular section, the rear torso outer tubular portion is fixed to a fixed base provided with a fixing member which detachably engages with the first fixing member engaging portion to fix the rear torso outer tubular portion to the rear torso inner tubular portion in a first state in which the length of the rear torso portion is relatively long, and which detachably engages with the second fixing member engaging portion to fix the rear torso outer tubular portion to the rear torso inner tubular portion in a second state in which the length of the rear torso portion is relatively short, and an expansion and contraction force transmission member which detachably engages with the transmission member engaging portion to fix the spreader of the shield jack to the rear torso outer tubular portion, and a restricting protrusion is formed on an inner surface side of the rear torso outer tubular portion of the spreader for restricting radial outward displacement of the rear torso outer tubular portion of the spreader.

The shield tunneling machine of the present invention described in claim 2 is the invention described in claim 1, characterized in that the restricting protrusions are formed at both ends on the inner circumferential surface side of the rear outer cylinder portion of the spreader.

The shield tunneling machine of the present invention described in claim 3 is characterized in that, in the invention described in claim 1 or 2, the first fixing member engaging portion, the second fixing member engaging portion, and the transmission member engaging portion are annular first fixing member grooves, second fixing member grooves, and transmission member grooves formed around the entire circumferential circumference of the inner peripheral surface of the rear barrel outer section, and smoothing members are removably installed in the second fixing member grooves and the transmission member grooves to make the second fixing member grooves and the transmission member grooves flush with the inner peripheral surface of the rear barrel outer section and prevent the spreader from getting stuck.

According to the present invention, it is possible to regulate the radially outward displacement of the rear outer barrel portion of the spreader by a regulating protrusion formed on the spreader, rather than by forming a protrusion on the inner peripheral surface of the rear outer barrel portion.

This does not impede movement as would be the case if a protrusion were provided on the inner peripheral surface of the rear outer barrel part that contacts the rear inner barrel part, and by moving the rear outer barrel part from the first state to the second state, the length of the rear barrel part can be shortened and curved construction can be performed smoothly. In addition, by moving the rear outer barrel part from the first state to the second state, the tail seal can be exposed inside the machine, making it possible to replace the tail seal from inside the shield machine.

1 is a schematic diagram showing the inside of a shield tunneling machine according to an embodiment of the present invention, seen from the side. FIG. FIG. 2 is a diagram showing the main components of the rear plate of the shield machine of FIG. 1 as viewed from the side. 2. FIG. 3 is a cross-sectional view showing the shield machine of FIG. 1 along line A of FIG. FIG. 4 is a diagram showing a part of FIG. 3 . 2. FIG. 3 is a cross-sectional view showing the shield machine of FIG. 1 along line B of FIG. FIG. 2 is a plan view showing a spreader and its surrounding mechanism in the shield machine of FIG. 1. FIG. 2 is a plan view showing a spreader and its surrounding mechanism in a shield machine as a comparative example. 2 is a plan view showing an expanded view of half of the inner circumferential surface of a rear outer cylinder section of a shield machine according to one embodiment of the present invention. FIG. FIG. 6 is a plan view showing the rear outer barrel portion along line C in FIG. 5 , developed in the axial direction. FIG. 6 is a plan view showing the rear outer barrel part along line D in FIG. 5 , developed in the axial direction. FIG. 6 is a plan view showing the rear outer barrel portion along line E in FIG. 5 , developed in the axial direction. 1A and 1B are diagrams showing one process of the contraction operation of the rear plate of the shield machine of Example 1, where FIG. 1A is a conceptual diagram shown from above, and FIG. 13A and 13B are diagrams showing the process following FIG. 12 in the contraction operation of the rear plate of the shield machine of the first embodiment, where FIG. 13A is a conceptual diagram shown from above, and FIG. 14A and 14B are diagrams showing the process following FIG. 13 in the contraction operation of the rear plate of the shield machine of the first embodiment, where FIG. 14A is a conceptual diagram shown from above, and FIG. 14B is an explanatory diagram shown from the side. 15A and 15B are diagrams showing the process following FIG. 14 in the contraction operation of the rear plate of the shield machine of the first embodiment, where (a) is a conceptual diagram shown from above, and (b) is an explanatory diagram shown from the side. 16A and 16B are diagrams showing the process following FIG. 15 in the contraction operation of the rear plate of the shield machine of the first embodiment, where (a) is a conceptual diagram shown from above, and (b) is an explanatory diagram shown from the side. 17A and 17B are diagrams showing the process following FIG. 16 in the contraction operation of the rear plate of the shield machine of the first embodiment, where (a) is a conceptual diagram shown from above, and (b) is an explanatory diagram shown from the side. 18A and 18B are diagrams showing the process following FIG. 17 in the contraction operation of the rear plate of the shield machine of the first embodiment, where (a) is a conceptual diagram shown from above, and (b) is an explanatory diagram shown from the side. 19A and 19B are diagrams showing the process following FIG. 18 in the contraction operation of the rear plate of the shield machine of the first embodiment, where (a) is a conceptual diagram shown from above, and (b) is an explanatory diagram shown from the side. 1A and 1B are diagrams showing one process of the extension operation of the rear plate of the shield machine of Example 1, where FIG. 1A is a conceptual diagram shown from above, and FIG. 1B is an explanatory diagram shown from the side. 20 in the extension operation of the rear plate of the shield machine of the first embodiment, where (a) is a conceptual diagram shown from above, and (b) is an explanatory diagram shown from the side. FIG. 22A and 22B are diagrams showing the process following FIG. 21 in the extension operation of the rear plate of the shield machine of the first embodiment, where FIG. 22A is a conceptual diagram shown from above, and FIG. 22B is an explanatory diagram shown from the side. 23A and 23B are diagrams showing the process following FIG. 22 in the extension operation of the rear plate of the shield machine of the first embodiment, where FIG. 23A is a conceptual diagram shown from above, and FIG. 23B is an explanatory diagram shown from the side. 24A and 24B are diagrams showing the process following FIG. 23 in the extension operation of the rear plate of the shield machine of the first embodiment, where FIG. 24A is a conceptual diagram shown from above, and FIG. 24B is an explanatory diagram shown from the side. 25A and 25B are diagrams showing the process following FIG. 24 in the extension operation of the rear plate of the shield machine of the first embodiment, where FIG. 25A is a conceptual diagram shown from above, and FIG. 25B is an explanatory diagram shown from the side. 26A and 26B are diagrams showing the process following FIG. 25 in the extension operation of the rear plate of the shield machine of the first embodiment, where (a) is a conceptual diagram shown from above, and (b) is an explanatory diagram shown from the side. 11A and 11B are diagrams showing one process of the procedure for replacing a tail seal in a shield machine of Example 2, where (a) is a conceptual diagram shown from above, and (b) is an explanatory diagram shown from the side. 27 in the procedure for replacing the tail seal in the shield machine of Example 2, where (a) is a conceptual diagram shown from above, and (b) is an explanatory diagram shown from the side. 28 in the procedure for replacing the tail seal in the shield machine of the second embodiment, where (a) is a conceptual diagram shown from above, and (b) is an explanatory diagram shown from the side. FIG. 30A and 30B are diagrams showing the process following FIG. 29 in the procedure for replacing the tail seal in the shield machine of the second embodiment, where (a) is a conceptual diagram shown from above, and (b) is an explanatory diagram shown from the side. 30 in the procedure for replacing the tail seal in the shield machine of Example 2, where (a) is a conceptual diagram shown from above, and (b) is an explanatory diagram shown from the side. FIG. 32A and 32B are diagrams showing the process following FIG. 31 in the procedure for replacing the tail seal in the shield machine of the second embodiment, where FIG. 32A is a conceptual diagram shown from above, and FIG. 32 in the procedure for replacing the tail seal in the shield machine of Example 2, where (a) is a conceptual diagram shown from above, and (b) is an explanatory diagram shown from the side. FIG. 34A and 34B are diagrams showing the process following FIG. 33 in the procedure for replacing the tail seal in the shield machine of the second embodiment, where FIG. 34A is a conceptual diagram shown from above, and FIG. 35A and 35B are diagrams showing the process following FIG. 34 in the procedure for replacing the tail seal in the shield machine of the second embodiment, where (a) is a conceptual diagram shown from above, and (b) is an explanatory diagram shown from the side. 35 in the procedure for replacing the tail seal in the shield machine of Example 2, where (a) is a conceptual diagram shown from above, and (b) is an explanatory diagram shown from the side. FIG. 36 in the procedure for replacing the tail seal in the shield machine of Example 2, where (a) is a conceptual diagram shown from above, and (b) is an explanatory diagram shown from the side. FIG. 37 in the procedure for replacing the tail seal in the shield machine of Example 2, where (a) is a conceptual diagram shown from above, and (b) is an explanatory diagram shown from the side. 38 in the procedure for replacing the tail seal in the shield machine of Example 2, where (a) is a conceptual diagram shown from above, and (b) is an explanatory diagram shown from the side. 40A and 40B are diagrams showing the process following FIG. 39 in the procedure for replacing the tail seal in the shield machine of the second embodiment, where (a) is a conceptual diagram shown from above, and (b) is an explanatory diagram shown from the side. 40 in the procedure for replacing the tail seal in the shield machine of Example 2, where (a) is a conceptual diagram shown from above, and (b) is an explanatory diagram shown from the side.

Below, an embodiment of the present invention will be described in detail with reference to the drawings. In the drawings for explaining the embodiment, the same components are generally designated by the same reference numerals, and repeated explanations will be omitted.

First, the overall configuration of the shield tunneling machine of this embodiment will be described with reference to Figure 1. Figure 1 is a schematic diagram of the main parts of the inside of the shield tunneling machine of this embodiment, seen from the side.

The shield tunneling machine 1 of this embodiment is a mud pressurizing type shield machine that excavates while ensuring the stability of the tunnel face by filling the chamber 4 between the cutter head 2 and the main body 3 with mud that is impermeable and has plastic fluidity (the ability to deform and move freely) created by injecting and mixing additives into the soil excavated by the cutter head 2, thereby generating mud pressure that counters the earth pressure at the tunnel face and ensuring the stability of the tunnel face.

The cutter head 2 is a shield cutter used to excavate the ground, and is installed in front of the tip head of the shield tunneling machine 1 in a state where it can rotate in both forward and reverse directions along the circumferential direction of the equipment body 3.

A center bit CB, a bit B, and scraper teeth (not shown) are attached to the front surface of the cutter head 2 (the surface facing the face). The center bit CB and the bit B are excavation parts that mainly cut away the natural ground, and the scraper teeth are cutting parts that mainly cut the natural ground. Note that instead of the bit B, for example, a roller cutter or the like may be attached.

A copy cutter CC is also installed on the outer periphery of the cutter head 2. The copy cutter CC is responsible for over-digging during curved construction and for controlling the attitude of the shield tunneling machine 1. In addition, multiple stirring rods SB are attached to the center periphery of the back surface of the cutter head 2. The stirring rods SB are formed, for example, from cylindrical protruding members, and have the role of stirring and mixing the soil and additives in the chamber 4 when the cutter head 2 rotates. The stirring rods SB are also equipped with, for example, a vibration sensor.

The equipment body 3 is the main component that drives the shield machine 1. The equipment that drives the shield machine 1 is surrounded and protected by a skin plate 5 that forms the outer shell of the equipment body 3. The skin plate 5 has a front body plate (front body section) 5a and a rear body plate (rear body section) 5b behind it. The front body plate 5a and the rear body plate 5b are made of, for example, cylindrical steel plates, and are engaged by the spherical bearing section at the tip of the rear body plate 5b entering into the front body plate 5a while in contact with the inner peripheral surface of the front body plate 5a.

The rear fuselage plate 5b is composed of a rear fuselage inner cylinder section 5ba located on the front fuselage plate 5a side, and a rear fuselage outer cylinder section 5bb installed following the rear fuselage inner cylinder section 5ba. The detailed structure of the rear fuselage plate 5b will be described later.

The hollow space inside the skin plate 5 is divided into a face side and an inboard 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 soil and sand excavated by the cutter head 2 are taken into the chamber 4 through a through hole (not shown) that penetrates the front and back surfaces of the cutter head 2.

On the other hand, on the inside of the hollow space of the skin plate 5, the cutter driver 8, the center bending jack 9a, the shield jack 9b, the screw conveyor 10, the erector 11, and the tail seals 12Ba, 12Bb are installed. In addition, a spreader 15 for transmitting the thrust of the shield jack 9b to a wide range of the segment SG (described later) is attached to the tip of the rod 9ba constituting the shield jack 9b via a block 9bb for aligning the position of the rod 9ba of the shield jack 9b with the position of the segment SG. In addition to the above, various other devices are installed in the main body 3, such as an earth pressure detector for detecting the earth pressure in the chamber 4 and an additive injection unit for injecting the above additive (earthworking mud material) into the chamber 4, although not shown in the figure.

The cutter drive body 8 is a motor (drive source) that rotates the cutter head 2 in forward and reverse directions, and multiple cutter drive bodies 8 are installed in a line near the outer periphery inside the front of the cutter head 2 along the circumferential direction of the cutter head 2. Note that a peripheral support drive system is exemplified here as the cutter drive system.

The bending jacks 9a are devices that correct the forward direction and posture of the shield tunneling machine 1, and are installed in a row along the circumferential direction of the equipment body 3, straddling the boundary between the front and rear plates 5a and 5b so as to connect the front and rear plates 5a and 5b within the equipment body 3. By supplying pressure oil to the bending jacks 9a and propelling the shield tunneling machine 1 with the front and rear plates 5a and 5b bent in a predetermined direction and angle, it is possible to control the forward direction and posture of the shield tunneling machine 1.

The shield jack 9b is a device that generates a driving force for advancing the shield tunneling machine 1 by using a reaction force from the segment SG installed at the rear of the equipment body 3, and is installed in the rear body inner cylinder portion 5ba that constitutes the rear body plate 5b. This shield jack 9b is arranged straddling the boundary between the front body plate 5a and the rear body plate 5b, and multiple shield jacks 9b are installed lined up along the circumferential direction of the equipment body 3.

The screw conveyor 10 is a device for discharging the soil and sand taken into the chamber 4 to the outside of the machine, and is installed so that it extends continuously from the chamber 4 through the partition wall 7 and diagonally upward toward the rear. Note that a ribbon screw conveyor is shown as an example here.

The erector 11 is an assembly device that grasps the segment SG, rotates it in the direction of the inner circumference of the excavation hole, and transports it to an assembly position in the direction of the inner circumference of the excavation hole. It is attached to an intermediate ring body 16 provided along the inner surface of the rear body inner cylindrical portion 5ba, and is installed in the hollow of the rear body plate 5b in a state in which it can rotate in the direction of the outer circumference of the excavation hole by a hydraulic motor (not shown) for driving the erector.

The tail seals 12Ba, 12Bb are provided at the rear end of the rear body outer cylinder portion 5bb that constitutes the rear body plate 5b between the inner circumference of the skin plate 5 and the outer circumference of the segment SG. They are water-stopping structures that prevent groundwater, soil, backfill material, etc. (hereinafter referred to as groundwater, etc.) from entering the inside of the equipment body 3 from the outside of the rear end side of the shield tunneling machine 1 during excavation work, and are composed of a metal brush with spring properties and elastic metal plates that are placed in front of, behind, and inside the brush so as to sandwich the brush.

The tail seals 12Ba, 12Bb are installed, for example, at two locations on the inner circumference of the rearmost end of the skin plate 5, spaced apart from each other along the front-to-rear direction of the shield tunneling machine 1 (the direction of the central axis of the shield tunneling machine 1, the extension direction of the excavation hole), and each tail seal 12Ba, 12Bb is installed in a ring-shaped arrangement along the inner circumference of the skin plate 5 so as to surround the outer periphery of the segment SG. A seal chamber 12R is formed between these tail seals 12Ba, 12Bb. The number of tail seals installed is not limited to two, and may be, for example, three or more locations along the front-to-rear direction of the shield tunneling machine 1.

Furthermore, each tail seal 12Ba, 12Bb is installed in a cantilevered state on the inner circumference of the skin plate 5. That is, one end side of each tail seal 12Ba, 12Bb (one end side in the front-to-rear direction of the device body 3) is fixed to the inner circumference of the skin plate 5, and is bent at an angle toward the segment SG between one end side and the other end side (the other end side in the front-to-rear direction of the device body 3) of the tail seal 12Ba, 12Bb, and further, the other end side of the tail seal 12Ba, 12Bb is pressed against the segment SG by the spring force of the tail seal 12Ba, 12Bb and is in contact with it.

In addition, a sealing agent supply pipe 14 is installed on the outer periphery of the rear body plate 5b. The sealing agent supply pipe 14 is a pipe for supplying a sealing agent such as grease to the sealing chamber 12R, and multiple sealing agent supply pipes 14 are installed on the outer periphery of the rear body plate 5b. By filling the sealing chamber 12R with sealing agent through this sealing agent supply pipe 14, the gap between the inner periphery of the skin plate 5 and the outer periphery of the segment SG is sealed, and together with the tail seals 12Ba, 12Bb, groundwater and the like is prevented from entering the inside of the shield tunneling machine 1 during excavation work.

Furthermore, a backfilling material supply passage (not shown) is installed on the outer wall of the rear body plate 5b. The backfilling material supply passage is a pipe for supplying backfilling material, for example, a cement-based hardening or solidifying material, to the gap between the excavation hole behind the skin plate 5 and the segment SG. By filling the gap between the excavation hole and the segment SG with backfilling material, ground subsidence is prevented, and the segment SG and the ground are integrated to prevent water leakage from the joints of the segment SG.

The backfilling material supply passages are provided, for example, at two locations on either side of the top of the skin plate 5. The sealant supply pipes 14 are provided at multiple locations on the outer periphery of the skin plate 5, whereas the backfilling material supply passages are only provided near the top of the skin plate 5. This is because the sealant has high viscosity and must be supplied evenly around the inner periphery of the skin plate 5 in order to adhere to the outer periphery of the segment SG, whereas the backfilling material has low viscosity and if it is supplied near the top of the skin plate 5, it will flow under its own weight to the lower outer periphery of the segment SG.

The locations and number of the sealant supply pipes 14 and backfilling material supply paths are not limited to those described above. For example, more sealant supply pipes 14 may be provided, and the backfilling material supply path may be provided at only one location at the axial top of the skin plate 5.

Next, the rear body plate 5b of the shield tunneling machine 1 will be described with reference to Figure 2. Figure 2 is a diagram showing the main components of the rear body plate 5b as seen from the side. In Figure 2, the rear body outer cylinder portion 5bb has moved so that the rear body plate 5b is in its longest state.

The structure of the rear body plate 5b will be explained. The rear body plate 5b is composed of the rear body inner cylinder section 5ba located on the front body plate 5a side, and the rear body outer cylinder section 5bb installed following the rear body inner cylinder section 5ba, and the rear body inner cylinder section 5ba and the rear body outer cylinder section 5bb partially overlap in the axial direction. In addition, the rear body outer cylinder section 5bb is movable in the axial direction so as to slide against the rear body inner cylinder section 5ba. Therefore, the total length of the rear body plate 5b expands and contracts due to the movement of the rear body outer cylinder section 5bb.

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

A fixing member 17 for fixing the rear outer barrel portion 5bb to the rear inner barrel portion 5ba so as to prevent the rear outer barrel portion 5bb from moving is detachably and selectively fitted (engaged) into the first fixing member groove 21 and the second fixing member groove 22 by a bolt. That is, as shown in the figure, the fixing member 17 fits into the first fixing member groove 21 and is fixed with a bolt to the fixing base 16a provided on the intermediate ring body 16 provided on the rear inner barrel portion 5ba, so that the rear outer barrel portion 5bb is fixed to the rear inner barrel portion 5ba in the extended position, that is, in the state where the length of the rear plate 5b is relatively long (first state). In addition, the rear outer barrel portion 5bb shrinks to a length where the position of the first fixing member groove 21 becomes the position of the second fixing member groove 22, and the fixing member 17 fits into the second fixing member groove 22 at that length and is fixed with a bolt to the fixing base 16a provided on the intermediate ring body 16 provided on the rear inner barrel portion 5ba, so that the rear outer barrel portion 5bb is fixed to the rear inner barrel portion 5ba in the contracted position, that is, in a state where the length of the rear plate 5b is relatively short (second state).

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

In addition, the transmission member groove 23 is adapted to removably fit (engage) an expansion and contraction force transmission member 18 (see FIG. 16, etc.) that is fixed to the shield jack 9b and moves the rear body outer cylinder portion 5bb in the axial direction by the expansion and contraction of the shield jack 9b. Therefore, the expansion and contraction of the shield jack 9b moves the rear body outer cylinder portion 5bb to the first state or the second state described above.

In this embodiment, the first fixing member engaging portion, the second fixing member engaging portion, and the transmission member engaging portion are formed as the first fixing member groove portion 21, the second fixing member groove portion 22, and the transmission member groove portion 23, which are formed in a concave shape, and are structured so that the fixing member 17 and the expansion and contraction force transmission member 18 fit into them, but they do not need to be concave, as long as they can engage with the fixing member 17 and the expansion and contraction force transmission member 18. However, as described below, since the spreader 15 moves by sliding against the inner circumferential surface of the rear body outer cylinder portion 5bb, if a block is provided to fasten the fixing member 17 and the expansion and contraction force transmission member 18 with a bolt, the block will protrude toward the inner diameter side and interfere with the spreader 15, which is not desirable.

Here, FIG. 3 is a cross-sectional view of the shield tunneling machine of FIG. 1 taken along line A in FIG. 2, FIG. 4 is a view showing an extracted portion of FIG. 3, and FIG. 5 is a cross-sectional view of the shield tunneling machine of FIG. 1 taken along line B in FIG. 2.

As shown in FIG. 3, an intermediate ring body 16 is provided in an annular shape along the inner peripheral surface of the rear body inner cylinder portion 5ba, and a plurality of shield jacks 9b (eight in this embodiment) are installed in the circumferential direction at regular intervals on the intermediate ring body 16. In addition, between the shield jacks 9b and the shield jacks 9b, a fixing member 17 for fixing the rear body outer cylinder portion 5bb to the rear body inner cylinder portion 5ba is positioned in a state where it is fitted into a first fixing member groove portion 21 formed in the rear body outer cylinder portion 5bb.

Furthermore, between the two shield jacks 9b at the top and bottom and the fixed member 17, rolling stoppers (regulating means) 19 are provided to regulate the circumferential displacement of the rear outer cylinder portion 5bb relative to the rear inner cylinder portion 5ba. The rolling stoppers 19 prevent rolling (circumferential displacement of the rear outer cylinder portion 5bb), which is likely to occur during curved construction as described below.

As shown in FIG. 4 and FIG. 8 described later, the rolling stopper 19 is composed of a fitting groove 19a extending along the axial direction of the rear outer barrel portion 5bb, and a fitting member 19b provided in the rear inner barrel portion 5ba that fits into the fitting groove 19a and can move along the fitting groove 19a. The fitting groove 19a is formed in a space sandwiched between a pair of plate-shaped bodies 20 installed parallel to each other on the inner peripheral surface of the rear outer barrel portion 5bb. In this embodiment, the fitting groove 19a is formed in the rear outer barrel portion 5bb, and the fitting member 19b is provided in the rear inner barrel portion 5ba. However, the fitting groove 19a may be formed in the rear inner barrel portion 5ba, and the fitting member 19b may be provided in the rear outer barrel portion 5bb.

As shown in FIG. 5, the spreader 15 attached to the tip of the shield jack 9b has a pressing surface 15f (the surface that faces the tip surface of the segment SG and presses the segment SG) that is formed in a generally arc shape in a front view that is longer along the circumferential direction of the rear trunk outer cylinder portion 5bb than the tip surface of the rod 9ba of the shield jack 9b or the tip surface of the block 9bb. This shape spreads the thrust of the shield jack 9b and transmits it to the segment SG.

In FIG. 5, legs (restriction protrusions) 15a are formed on both ends of the spreader 15 on the inner peripheral surface side of the rear outer barrel portion 5bb to restrict the spreader 15 from being displaced radially outward of the rear outer barrel portion 5bb.

The spreader 15 is attached to the tip of the block 9bb to align the position of the rod 9ba of the shield jack 9b with the position of the segment SG, and as shown in FIG. 2, the part of the block 9bb that pushes the segment SG (i.e., the part to which the spreader 15 is attached) is located radially outward of the rear barrel outer cylinder 5bb than the part that is pushed by the rod 9ba of the shield jack 9b. Therefore, when the shield jack 9b pushes the segment SG, the spreader 15 tries to displace radially outward of the rear barrel outer cylinder 5bb. At this time, if the leg 15a that restricts the radially outward displacement of the rear barrel outer cylinder 5bb is not formed, the radially outward displacement of the rear barrel outer cylinder 5bb of the spreader 15 is permitted, and when the shield jack 9b is extended and the shield tunneling machine 1 is excavated, a force that spreads radially outward acts on the annular segment SG that is pushed by the spreader 15. On the other hand, if the legs 15a are formed as in this embodiment, no force acts on the segment SG to spread radially outward.

In this embodiment, the radial outward displacement of the rear outer barrel portion 5bb of the spreader 15 is restricted by two protrusions, that is, legs 15a, formed at both ends of the inner peripheral surface of the rear outer barrel portion 5bb of the spreader 15, but the protrusions may be in one location or in three or more locations.

In addition, instead of forming protrusions such as legs 15a on the spreader 15 side, it is also possible to form protrusions on the inner surface of the rear barrel outer cylinder 5bb to restrict the displacement of the spreader 15. However, in the shield tunneling machine 1 of this embodiment, as described above, the rear barrel outer cylinder 5bb moves in the axial direction by sliding against the rear barrel inner cylinder 5ba, so providing a protrusion on the inner surface of the rear barrel outer cylinder 5bb that contacts the rear barrel inner cylinder 5ba would hinder movement. Therefore, providing such a protrusion is undesirable.

The inner peripheral surface of the rear outer barrel section 5bb is formed with the first fixing member groove 21, the second fixing member groove 22, and the transmission member groove 23. Therefore, when the spreader 15 reaches the position of the grooves 22 and 23, the legs 15a will fit into the grooves 22 and 23. To prevent this, it is necessary to make the grooves 22 and 23 where the legs 15a of the spreader 15 pass flush with the inner peripheral surface of the rear outer barrel section 5bb. The member (flat plate 24) for making the fixing member groove 22 and the transmission member groove 23 where the legs 15a pass flush with the inner peripheral surface of the rear outer barrel section 5bb will be described later.

Here, FIG. 6 is a plan view of the spreader and its surrounding mechanism in this embodiment, and FIG. 7 is a plan view of the spreader and its surrounding mechanism as a comparative example.

As shown in FIG. 6, in the spreader 15 of this embodiment, a concave portion 15b is formed on the surface opposite to the pressing surface 15f to avoid interference with the fixed member 17 when the shield jack 9b is fully contracted. If the concave portion 15b is not formed, the retraction position of the spreader 15 cannot be made further forward, as shown in FIG. 7, in order to prevent the spreader 15 from interfering with the fixed member 17 when the shield jack 9b is fully contracted. On the other hand, if the concave portion 15b is formed as in this embodiment, even if the retraction position of the spreader 15 when the shield jack 9b is fully contracted is further forward than in the case shown in FIG. 7, the spreader 15 will not interfere with the fixed member 17. This makes it possible to maximize the retraction amount of the rear outer barrel portion 5bb relative to the rear inner barrel portion 5ba when the shield jack 9b is contracted, and the length of the rear plate 5b in the second state described above can be made shorter.

Figure 8 is a plan view showing half of the inner circumferential surface of the rear barrel outer tube in a shield tunneling machine according to one embodiment of the present invention, Figure 9 is a plan view showing the rear barrel outer tube part in the axial direction along line C in Figure 5, Figure 10 is a plan view showing the rear barrel outer tube part in the axial direction along line D in Figure 5, and Figure 11 is a plan view showing the rear barrel outer tube part in the axial direction along line E in Figure 5.

In FIG. 8, the rear barrel outer cylinder 5bb of the shield machine 1 is formed with the first fixing member groove 21, the second fixing member groove 22, and the transmission member groove 23. As shown in the figure, the fixing member grooves 21, 22 and the transmission member groove 23 are annular grooves formed around the entire circumference of the inner surface of the rear barrel outer cylinder 5bb. To specifically explain the process of forming the fixing member grooves 21, 22 and the transmission member groove 23, two flat rear barrel outer cylinders 5bb are made, each of which is bent into a semicircular shape and the ends are welded together to obtain the cylindrical rear barrel outer cylinder 5bb. Then, the inner circumference of the rear barrel outer cylinder 5bb is cut with a lathe to form the fixing member grooves 21, 22 and the transmission member groove 23, which are annular grooves.

The first fixing member groove 21, the second fixing member groove 22, and the transmission member groove 23 do not need to be formed in an annular shape around the entire circumference of the inner circumferential surface of the rear barrel portion 5bb as in this embodiment, but may be formed in spots at the locations where the fixing member 17 and the expansion/contraction force transmission member 18 are fixed.

However, if the first fixing member groove 21, the second fixing member groove 22, and the transmission member groove 23 are formed in spots, they must be formed only in specific, discontinuous locations, which is time-consuming and can cause thermal stress on the metal rear barrel outer tube portion 5bb, resulting in distortion. However, if they are formed in a ring shape as in this embodiment, such problems do not occur.

Now, as shown in FIG. 9, holes 21a and 22a are formed in the axial direction of the rear barrel outer cylinder portion 5bb along line C in FIG. 5 for fitting the aforementioned fixing member 17 into the first fixing member groove portion 21 and the second fixing member groove portion 22 and fixing it to the rear barrel outer cylinder portion 5bb with a bolt.

As shown in FIG. 10, a hole 23a is formed in the axial direction of the rear outer barrel portion 5bb along line D in FIG. 5 for fitting the expansion and contraction force transmission member 18 into the transmission member groove 23 and fixing it to the rear outer barrel portion 5bb with a bolt.

Furthermore, as shown in Fig. 11, a flat plate (smoothing member) 24 is provided in the axial direction of the rear outer barrel portion 5bb along line E in Fig. 5 to make the second fixing member groove 22 and the transmission member groove 23 flush with the inner peripheral surface of the rear outer barrel portion 5bb and prevent the spreader 15 from getting stuck. That is, as described above, since the leg 15a of the spreader 15 moves along the inner peripheral surface of the rear outer barrel portion 5bb, if no measures are taken, the leg 15a of the spreader 15 will get stuck in the second fixing member groove 22 and the transmission member groove 23 and will not be able to move smoothly. Therefore, by installing the flat plate 24 at the point where the leg 15a of the spreader 15 passes through the second fixing member groove 22 and the transmission member groove 23, the leg 15a is prevented from getting stuck. If the legs 15a are not provided, a flat plate 24 is installed at the location where the entire spreader 15 passes through the second fixing member groove 22 and the transmission member groove 23.

In this embodiment, the range of the fixing member 17 when fitted and fixed in the second fixing member groove 22 overlaps with the range through which the spreader 15 (more specifically, the leg 15a of the spreader 15 in contact with the inner peripheral surface of the rear trunk outer cylinder portion 5bb) passes (i.e., the portion of the flat plate 24 installed in the second fixing member groove 22). Therefore, when fitting the fixing member 17 into the second fixing member groove 22, it interferes with the flat plate 24 installed in the second fixing member groove 22, so it becomes necessary to remove the flat plate 24. Therefore, as shown in FIG. 11, the flat plate 24 of the second fixing member groove 22 is removable by bolting. However, as long as the position of the fixing member 17 when fitted into the second fixing member groove 22 does not overlap with the location through which the spreader 15 passes, the flat plate 24 installed in the second fixing member groove 22 may also be fixed to the rear body outer cylinder portion 5bb.

In addition, in this embodiment, the range of the elastic force transmission member 18 when fitted and fixed in the transmission member groove 23 does not overlap with the range through which the spreader 15 (more specifically, the leg 15a of the spreader 15 in contact with the inner circumferential surface of the rear body outer cylinder 5bb) passes (i.e., the portion of the flat plate 24 installed in the transmission member groove 23). Therefore, even if the elastic force transmission member 18 is fitted into the transmission member groove 23, it does not interfere with the flat plate 24 installed in the transmission member groove 23, 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 transmission member groove 23. Therefore, as shown in FIG. 11, the flat plate 24 of the transmission member groove 23 is fixed to the rear body outer cylinder 5bb. However, when the range in which the expansion and contraction force transmission member 18 is fitted into the transmission member groove 23 overlaps with the range through which the spreader 15 passes, the flat plate 24 installed in the transmission member groove 23 can be attached and detached by bolting.

It is preferable to fix the flat plate 24 to the rear outer cylinder portion 5bb by staggered welding (intermittent fillet welding in which welded and unwelded portions alternate) to reduce heat input during welding.

(Example 1)

Next, as Example 1, the telescopic movement of the rear body plate 5b in the shield machine 1 having the above configuration will be described with reference to Figs. 12 to 26. Here, Figs. 12 to 19 are diagrams successively showing the contraction movement of the rear body plate of the shield machine in Fig. 1, and Figs. 20 to 26 are diagrams successively showing the extension movement of the rear body plate of the shield machine in Fig. 1. In these drawings, (a) is a conceptual diagram of the rear body plate seen from above, and (b) is an explanatory diagram of the rear body plate seen from the side. Also, (a) shows a pair of adjacent shield jacks out of the eight shield jacks installed in this example, and the other pairs of shield jacks operate in the same way.

In the shield tunneling machine 1 in which the rear body plate 5b is extended and retracted, the dimensions of the rear body outer cylinder 5bb in the first state in FIG. 2 are as follows: the length of the part not overlapping with the rear body inner cylinder 5ba (effective length: FL) is 1970 mm, the length of the effective length other than the tail seals 12Ba, 12Bb (L1) is 1490 mm, the length of the tail seals 12Ba, 12Bb (L2) is 480 mm, and the distance (L3) between the first fixing member groove 21 and the second fixing member groove 22 is 300 mm. The movable length of the rear body outer cylinder 5bb is 300 mm, since it corresponds to the distance (L3) between the first fixing member groove 21 and the second fixing member groove 22. However, these dimensions are merely examples, and the present invention is not limited to these dimensions.

First, we will explain the contraction operation of the rear body plate 5b of the shield tunneling machine 1 (the operation in which the rear body outer cylinder portion 5bb moves from the first state to the second state). Note that the rear body plate 5b is contracted mainly when transitioning from straight construction to curved construction.

As shown in Figure 12, in linear construction, the rear body outer cylinder portion 5bb is placed in the first state to lengthen the length of the rear body plate 5b, and segments SG, for example 900 mm wide, are continuously installed in the excavation hole. In this state, the fixing member 17 is fitted into the first fixing member groove 21 and fixed to the fixing base 16a, and a flat plate 24 is installed in the second fixing member groove 22. The segments SG are assembled into a ring shape inside the shield machine 1 to form a tunnel, and are tunnel lining members.

To move from here to curved construction, the rear outer cylinder section 5bb is put into the second state and the rear plate 5b is contracted to shorten its length. First, as shown in FIG. 13, the shield jack 9b is stroked a predetermined length (a length that allows the expansion and contraction force transmission member 18 to fit into the transmission member groove 23) to advance the shield tunneling machine 1, and a space sufficient for assembling a segment SG, for example 300 mm wide, for curved construction is created.

Next, the flat plate 24 installed in the second fixing member groove 22 is removed, and as shown in FIG. 14, the fixing member 17 fixed to the fixing base 16a is removed and moved from the first fixing member groove 21 to the second fixing member groove 22.

Next, as shown in FIG. 15, some of the shield jacks 9b are pressed against the segments SG (i.e., buckling prevention measures are taken to prevent the shield tunneling machine 1 from retreating), and the other shield jacks 9b are pulled for a certain length. The length by which the shield jacks 9b are pulled is a length that allows the extension force transmission member 18, described later, to be fitted into the transmission member groove 23 and fixed to the tip of the shield jack 9b, and a spacer 18a (FIG. 20, etc.) to be attached to the tip. In this embodiment, the buckling prevention measures are taken with a total of four shield jacks 9b, two at the top and two at the bottom. However, it goes without saying that buckling prevention measures may be taken with shield jacks 9b other than these.

Next, as shown in FIG. 16, the expansion and contraction force transmission member 18 is fitted into the transmission member groove 23 and fixed to the rear body outer cylinder portion 5bb with a bolt, and then fixed to the tip of the shield jack 9b (more specifically, to the spreader 15 provided on the shield jack 9b) with a tension bolt.

Next, as shown in FIG. 17, the shield jack 9b is pulled to a position where the fixing member 17 fitted into the second fixing member groove 22 hits the fixing base 16a. This causes the rear body outer cylinder 5bb to move forward, resulting in a second state in which the length of the rear body plate 5b is relatively shortened. Here, the distance between the first fixing member groove 21 and the second fixing member groove 22 (the length of L3 in FIG. 2) is 300 mm, so the length of the rear body plate 5b is shortened by 300 mm.

Once the rear trunk outer cylinder section 5bb has moved forward in this way, the fixing member 17 is fixed to the fixing base 16a with a bolt, and as shown in Figure 18, the extension force transmission member 18 is removed and the shield jack 9b is further pulled. This completes the transition to a curve construction state in which the curve can be smoothly constructed with good curve conformity.

After that, while performing curved excavation with the shield tunneling machine 1, segments SG for curved construction (e.g., 300 mm wide segments SG) are installed as shown in Figure 19.

Next, we will explain the extension operation of the rear body plate 5b of the shield tunneling machine 1 (the operation in which the rear body outer cylinder portion 5bb moves from the second state to the first state). Note that the rear body plate 5b is mainly extended when transitioning from curved construction to straight construction.

When the curved construction is completed with the rear body outer cylinder section 5bb in the second state and the rear body plate 5b shortened, as shown in FIG. 20, some of the shield jacks 9b are pressed against the segment SG, and the expansion and contraction force transmission member 18 is fitted into the transmission member groove 23 on the extension line of the other shield jacks 9b and fixed to the rear body outer cylinder section 5bb with bolts. Furthermore, a spacer 18a is attached to the segment SG side of the expansion and contraction force transmission member 18. As shown in the figure, a small gap is formed between the spacer 18a attached to the expansion and contraction force transmission member 18 and the segment SG because space is required to attach the spacer 18a to the expansion and contraction force transmission member 18.

Next, as shown in FIG. 21, the shield jack 9b is extended to bring the spreader 15 into contact with the expansion and contraction force transmission member 18, and the fixing member 17 fitted into the second fixing member groove 22 is removed. As a result, the rear body outer cylinder portion 5bb is released from the fastening with the fixing base 16a provided on the intermediate ring body 16, and becomes movable in the axial direction.

Next, as shown in FIG. 22, the shield jack 9b is extended to press the spacer 18a against the segment SG, moving the rear inner cylinder 5ba forward and positioning the fixing member 17 so that it can be fitted into the first fixing member groove 21 and fixed to the fixing base 16a. This moves the rear inner cylinder 5ba forward, resulting in a first state in which the length of the rear plate 5b is relatively longer. Here, the distance between the first fixing member groove 21 and the second fixing member groove 22 (the length of L3 in FIG. 2) is 300 mm, so the length of the rear plate 5b is increased by 300 mm.

As mentioned above, a small gap is formed between the spacer 18a and the segment SG, so when the shield jack 9b extends and the spacer 18a is pressed against the segment SG via the extension force transmission member 18, the rear body outer cylinder portion 5bb moves backward by the amount of the gap. Then, the tail seals 12Ba, 12Bb move backward in the opposite direction to their normal movement (forward movement) relative to the segment SG. However, because the amount of movement is small and corresponds to the aforementioned gap, no problems such as deformation of the tail seals 12Ba, 12Bb occur.

Next, as shown in FIG. 23, the fixing member 17 is fitted into the first fixing member groove 21 and fixed to the fixing base 16a, and is also fixed to the rear barrel portion 5bb with a bolt. In addition, a flat plate 24 is installed in the second fixing member groove 22.

Next, as shown in Figure 24, the shield jack 9b without the expansion and contraction force transmission member 18 and spacer 18a attached is pressed against the segment SG. Then, the shield jack 9b with the expansion and contraction force transmission member 18 and spacer 18a attached is pulled slightly to form a gap between the spacer 18a and the segment SG, and the expansion and contraction force transmission member 18 and spacer 18a are removed.

Next, as shown in FIG. 25, the shield jack 9b is extended to move the shield tunneling machine 1 forward, creating sufficient space to assemble the segments SG for linear construction.

Next, as shown in Figure 26, when the shield jack 9b is pulled, the transition to the straight line construction state, which allows for smooth straight line construction, is completed.

After that, linear excavation is performed with the shield tunneling machine 1 while installing linear construction segments SG (for example, 900 mm wide segments SG).

In this way, according to the shield tunneling machine 1 of this embodiment, the rear body outer cylinder 5bb constituting the rear body plate 5b is able to move in the axial direction by sliding against the rear body inner cylinder 5ba, and the movement of the rear body outer cylinder 5bb expands or contracts the overall length of the rear body plate 5b. Therefore, by moving the rear body outer cylinder 5bb from the first state to the second state, it is possible to smoothly carry out curved construction. This not only improves the ability to follow the curve, but also prevents excessive over-excavation.

(Example 2)

Next, as a second embodiment, the replacement of the tail seal 12Ba in a shield machine 1 having the above configuration will be described with reference to Figs. 27 to 41. Here, Figs. 27 to 41 are diagrams successively showing the procedure for replacing the tail seal of the shield machine of the second embodiment. In these drawings, (a) is a conceptual diagram of the rear body plate seen from above, and (b) is an explanatory diagram of the rear body plate seen from the side. Also, (a) shows a pair of adjacent shield jacks out of the eight shield jacks installed in this embodiment, and the other pairs of shield jacks operate in the same way.

In the shield tunneling machine 1 in which the tail seal 12Ba is replaced, the dimensions of the rear body outer cylinder 5bb in the first state in FIG. 2 are as follows: the length (effective length: FL) of the part not overlapping with the rear body inner cylinder 5ba is 1610 mm, the length (L1) of the effective length other than the tail seals 12Ba, 12Bb is 1130 mm, the length (L2) of the tail seals 12Ba, 12Bb is 480 mm, and the distance (L3) between the first fixing member groove 21 and the second fixing member groove 22 is 350 mm. The movable length of the rear body outer cylinder 5bb is 350 mm, since it corresponds to the distance (L3) between the first fixing member groove 21 and the second fixing member groove 22. However, these dimensions are merely examples, and the present invention is not limited to these dimensions.

The tail seal to be replaced is the tail seal 12Ba located at the front of the two tail seals 12Ba, 12Bb. This is because the tail seal 12Bb located at the rear is directly subjected to pressure from groundwater and soil, and therefore cannot be removed for replacement.

The dimensions of the rear fuselage outer cylinder 5bb described above allow the tail seal 12Ba located at the front to come off the segment SG and be exposed inside the aircraft when the rear fuselage outer cylinder 5bb is in the second state (a position where the length of the rear fuselage plate 5b is relatively short).

Now, when replacing the tail seal 12Ba, the rear outer barrel portion 5bb is placed in the first state as shown in Figure 27. In this first state, the fixing member 17 is fitted into the first fixing member groove 21 and fixed to the fixing base 16a, and the flat plate 24 is installed in the second fixing member groove 22.

Next, as shown in FIG. 28, the shield jack 9b is stroked a predetermined length (a length that allows the expansion and contraction force transmission member 18 to fit into the transmission member groove portion 23) to move the shield tunneling machine 1 forward.

Next, the flat plate 24 installed in the second fixing member groove 22 is removed, and then the fixing member 17 is removed from the rear barrel inner cylinder portion 5ba, and the removed fixing member 17 is transferred to the second fixing member groove 22 as shown in FIG. 29.

Next, as shown in Figure 30, some of the shield jacks 9b (in the case shown in Figure 30(a), the lower shield jack 9b) are pressed against the segment SG (i.e., the buckling prevention measures are in place), and the other shield jacks 9b (in the case shown in Figure 30(a), the upper shield jack 9b) are pulled out for a predetermined length and pressed against the segment SG via the buckling prevention member 25.

Next, as shown in Figure 31, the shield jack 9b (the lower shield jack 9b in the case shown in Figure 31 (a)) pressed against the segment SG is pulled to a certain length, and the expansion and contraction force transmission member 18 is fitted into the transmission member groove 23 and fixed to the rear body outer cylinder portion 5bb with a bolt, and the tip of the shield jack 9b (more specifically, to the spreader 15 provided on the shield jack 9b) is fixed with a tension bolt.

Next, as shown in FIG. 32, the shield jack 9b to which the telescopic force transmission member 18 is fixed is pulled a predetermined length to pull in the rear body external cylinder 5bb. More specifically, the shield jack 9b is pulled to a position where the fixing member 17 fitted into the second fixing member groove 22 hits the fixing base 16a. As a result, the rear body external cylinder 5bb moves forward, and the rear body plate 5b enters a second state in which its length is relatively shortened. Here, the distance between the first fixing member groove 21 and the second fixing member groove 22 (length L3 in FIG. 2) is 350 mm, so the length of the rear body plate 5b is shortened by 350 mm. Then, as the rear body external cylinder 5bb moves forward, the tail seal 12Ba comes off the segment SG and is exposed inside the aircraft, as shown in the figure. The fixing member 17 is fixed to the fixing base 16a with bolts.

Next, as shown in Figure 33, the tail seal 12Ba that does not interfere with the buckling prevention member 25 is replaced with a new tail seal 12Ba. Note that in Figure 33, the tail seal 12Ba that is to be replaced is indicated by a cross-hatched line.

After replacing part of the tail seal 12Ba in this way, as shown in Figure 34, remove the expansion and contraction force transmission member 18 from the transmission member groove 23, interpose the buckling prevention member 25 between the removed shield jack 9b and the segment SG, and extend the shield jack 9b to press the buckling prevention member 25 against the segment SG.

Next, as shown in FIG. 35, the buckling prevention member 25 located in the part of the tail seal 12Ba that has not been replaced is removed, and the expansion and contraction force transmission member 18 is fitted into the transmission member groove 23 and fixed to the rear body outer cylinder part 5bb with a bolt and fixed to the tip of the shield jack 9b (more specifically, to the spreader 15 provided on the shield jack 9b) with a tension bolt. However, since the buckling prevention member 25 is interposed between the shield jack 9b and the segment SG in the part where the tail seal 12Ba has been replaced, and the fixing member 17 is fixed to the fixing base 16a, the installation of the expansion and contraction force transmission member 18 may be omitted.

After swapping the position of the buckling prevention member 25 in this way, as shown in Figure 36, the part of the tail seal 12Ba that no longer interferes with the buckling prevention member 25 (i.e., the remaining part of the tail seal 12Ba) is replaced with a new tail seal 12Ba. This results in the entire tail seal 12Ba being replaced.

Then, as shown in FIG. 37, the buckling prevention member 25 is removed and the segment SG is installed. The new tail seal 12Ba, which was exposed inside the machine, is then pushed radially outward by the segment SG and positioned on the outer periphery of the installed segment SG. This completes the replacement of the tail seal 12Ba in the shield tunneling machine 1. With the segment SG installed, buckling prevention is performed by the shield jack 9b to which the expansion and contraction force transmission member 18 is not fixed.

Once the replacement of the tail seal 12Ba is completed and the segment SG is installed in this manner, as shown in FIG. 38, a spacer 18a is attached to the segment SG side of the expansion and contraction force transmission member 18, and the fixing member 17 fitted into the second fixing member groove 22 is removed. This releases the rear body outer cylinder section 5bb from the fixing base 16a and allows it to move in the axial direction. As shown in the figure, a small gap is formed between the spacer 18a attached to the expansion and contraction force transmission member 18 and the segment SG, because space is required to attach the spacer 18a to the expansion and contraction force transmission member 18.

Next, as shown in FIG. 39, the shield jack 9b is extended to move the rear inner cylinder 5ba forward, and the fixing member 17 is fitted into the first fixing member groove 21 and fixed to the fixing base 16a, and is also fixed to the rear outer cylinder 5bb with a bolt. In addition, a flat plate 24 is installed in the second fixing member groove 22. This causes the rear inner cylinder 5ba to move forward, resulting in a first state in which the length of the rear plate 5b is relatively longer. Here, the distance between the first fixing member groove 21 and the second fixing member groove 22 (the length of L3 in FIG. 2) is 350 mm, so the length of the rear plate 5b is increased by 350 mm.

As mentioned above, a small gap is formed between the spacer 18a and the segment SG, so when the shield jack 9b extends and the spacer 18a is pressed against the segment SG via the extension force transmission member 18, the rear body outer cylinder portion 5bb moves backward by the amount of the gap. Then, the tail seals 12Ba, 12Bb move backward in the opposite direction to their normal movement (forward movement) relative to the segment SG. However, because the amount of movement is small and corresponds to the aforementioned gap, no problems such as deformation of the tail seals 12Ba, 12Bb occur.

Next, as shown in FIG. 40, while the shield jack 9b without the expansion force transmission member 18 and spacer 18a attached is pressed against the segment SG, the shield jack 9b with the expansion force transmission member 18 and spacer 18a attached is slightly pulled to form a gap between the spacer 18a and the segment SG, and the expansion force transmission member 18 and spacer 18a are removed.

Next, as shown in Figure 41, pull the shield jack 9b to install the segment SG.

In this way, according to the shield tunneling machine 1 of this embodiment, the rear body outer cylinder portion 5bb constituting the rear body plate 5b is able to move axially by sliding against the rear body inner cylinder portion 5ba, so that by moving the rear body outer cylinder portion 5bb from the first position to the second position, the tail seal 12Ba is released from the segment SG and exposed inside the machine. Therefore, it is possible to replace the tail seal 12Ba from inside the shield machine. This makes it possible to prevent problems caused by deterioration or damage to the tail seal 12Ba.

The invention made by the inventor has been specifically described above based on the embodiments, but the embodiments disclosed in this specification are illustrative in all respects and are not limited to the disclosed technology. In other words, the technical scope of the present invention should not be interpreted restrictively based on the explanation in the above embodiments, but should be interpreted strictly according to the description of the claims, and includes technologies equivalent to the technologies described in the claims and all modifications that do not deviate from the gist of the claims.

In the above explanation, the present invention has been described as being applied to an earth pressure shield machine, but the present invention is not limited to this, and can also be applied to other shield machines, such as an earth pressure shield machine that stabilizes the face by applying a predetermined pressure to the earth pressure in the chamber and transports the excavated earth by circulating the earth pressure.

1 Shield tunneling machine 2 Cutter head 3 Machine body 5 Skin plate 5a Front body plate (front body)
5b Rear fuselage plate (rear fuselage section)
5ba: Rear body inner cylinder portion 5bb: Rear body outer cylinder portion 9a: Center bending jack 9b: Shield jack 9ba: Rod 9bb: Blocks 12Ba, 12Bb: Tail seal 12R: Seal chamber 15: Spreader 15a: Leg portion (regulating protrusion)
15b: concave portion 15f: pressing surface 16: intermediate ring body 16a: fixed base 17: fixed member 18: expansion/contraction force transmission member 18a: spacer 19: rolling stopper (regulating means)
19a Fitting groove 19b Fitting member 20 Plate-shaped body 21 First fixing member groove portion (first fixing member engagement portion)
22 Second fixing member groove portion (second fixing member engagement portion)
23 Groove portion for transmission member (engagement portion for transmission member)
21a, 22a, 23a Hole 24 Flat plate (smoothing member)
25 Buckling prevention member SG segment

Claims (3)

A forward body where the cutter head is installed;
a rear barrel section having a rear barrel inner section located on the forward barrel section side and provided with a plurality of shield jacks each having a spreader attached to a tip thereof, and a rear barrel outer section subsequent to the rear barrel inner section, the rear barrel outer section being installed so as to partially overlap with the rear barrel inner section and being movable in the axial direction;
Equipped with
The rear outer barrel portion has
a first fixing member engaging portion, a second fixing member engaging portion, and a transmission member engaging portion each formed in a circumferentially concave shape from the front to the rear on an inner circumferential surface;
a fixing member that is fixed to a fixing base that is provided on an intermediate ring body that is provided annularly on the rear trunk inner cylindrical portion along an inner circumferential surface of the rear trunk inner cylindrical portion, and that detachably engages with the first fixing member engaging portion to fix the rear trunk outer cylindrical portion to the rear trunk inner cylindrical portion in a first state in which the length of the rear trunk portion is relatively long, and that detachably engages with the second fixing member engaging portion to fix the rear trunk outer cylindrical portion to the rear trunk inner cylindrical portion in a second state in which the length of the rear trunk portion is relatively short;
an expansion/contraction force transmission member that detachably engages with the transmission member engagement portion to fix the spreader of the shield jack to the rear trunk outer cylinder portion;
a restricting protrusion that restricts radial outward displacement of the spreader of the rear outer barrel portion is formed on an inner peripheral surface side of the rear outer barrel portion of the spreader;
A shield tunneling machine characterized by: The restriction protrusions are formed at both ends of the inner circumferential surface of the rear outer cylinder portion of the spreader.
2. A shield tunneling machine according to claim 1. the first engaging portion for a fixing member, the second engaging portion for a fixing member, and the engaging portion for a transmitting member are annular first groove for a fixing member, a second groove for a fixing member, and a groove for a transmitting member, respectively, formed over the entire circumference in the circumferential direction of an inner circumferential surface of the rear outer barrel portion,
a smoothing member for preventing the spreader from getting caught by making the second fixing member groove and the transmitting member groove flush with an inner circumferential surface of the rear trunk outer cylinder portion, the smoothing member being detachably installed in the second fixing member groove and the transmitting member groove.
3. A shield tunneling machine according to claim 1 or 2.

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