JP4202218B2 - Muddy water shield machine - Google Patents

Description

  The present invention relates to a so-called eccentric multi-axis cutter rotation type mud water shield machine that rotates a cutter by an eccentric multi-axis mechanism to excavate natural ground, promotes a shield machine, and prevents collapsing of a face by muddy water pressure. .

  In this type of eccentric multi-axis cutter rotation type mud shield machine, mud pressure is used as a method of stabilizing the face. However, even when mud pressure is applied to the face, it is difficult to maintain the stability of the face in a homogeneous sand ground (equal coefficient of 10 or less, particularly 4 or less) with poor self-sustainability.

  In many cases, the collapse of the face is considered to occur from the vicinity of the top end of the face as shown in the schematic diagrams of FIGS. 7 and 8, reference numeral 33 denotes a core part of the face collapse, and an outline of the case where the range of the face collapse expands to reference numerals 33 to 34 is shown.

  The shape of the cutter in the eccentric multi-axis cutter rotation method has a small diameter by a length twice as long as the cutter rotation radius compared to the shield outer diameter. The cutter rotates while being biased by the difference between the shape of the cutter and the outer diameter of the shield.

  An opening without a cutter is generated on the opposite face surface where the cutter is biased. When the offset position of the cutter moves to the lower end of the cross-sectional shape of the shield machine and stops, an opening is generated at the top end of the face, and the face is most likely to collapse. When stopping the shield excavation, the cutter is often placed in a state where no eccentric rotational torque is generated, that is, at the lower end of the cross-sectional shape of the shield machine.

  Conventionally, the shape of the cutter of the muddy water shield machine is a face plate type. A slit is provided in a part of the face plate, and excavated earth and sand are taken from the slit. The stability of the face is based mainly on the stability of the mud water pressure, and the face is supplemented by the face plate.

  In recent years, improvement of mud materials has progressed, the permeability to natural ground and the effect of preventing mud loss have been improved, and the stability of the face has increased without expecting the face plate. Therefore, there is almost no need for the clogging of the slit, which has been performed in order to increase the stability of the face when the cutter excavation is stopped.

  For this reason, it has been considered that the face plate that has been required for the muddy water shield machine is not necessarily required in the soil conditions where the independence of the face can be expected by suppressing the groundwater pressure. . However, in consideration of uncertain elements in the soil such as soil changes and stability, the face plate shape of the cutter is currently adopted as it is.

  By the way, shield excavation is subject to restrictions on the form of work and may be forced to stop for several days. It is necessary to ensure the stability of the face even during this stop period.

  In a muddy water shield machine, if the cutter has a cross-sectional shape for the entire cross section, the cutter is in contact with the top edge of the face, which is most likely to collapse, and the face is stably suppressed over a long period of time together with the muddy water effect. be able to.

  However, in the shield machine of the eccentric multi-axis cutter rotation method, as described above, the cutter shape is smaller than the shield outer diameter. Therefore, when the cutter is decentered at the lower end of the cross-sectional shape of the shield machine and stopped, there is no cutter that can suppress the face.

  In addition, the stability of the face during shield digging can be secured by improving the muddy water material, but when shield digging is stopped for a long period of time, a means to suppress the collapse of the top edge of the face is particularly necessary. Become.

In addition, there exists the following patent document as a prior art of the mud shield machine with the function which prevents the collapse of a face.
Japanese Patent No. 3100133

  The present invention has been made in view of the above circumstances, and the object of the present invention is when there is a risk of collapsing the face during shield excavation, and the position of the cutter bias in the lower end of the cross-sectional shape of the shield machine. To provide a muddy water shield machine capable of accurately preventing the face from collapsing even when the cutter is stopped in a state where the face is moved, and when the opening is generated at the top end of the face, for a long period of time. is there.

  Another object of the present invention is to provide a muddy water shield machine that can prevent the collapse of the face more accurately.

In order to achieve the above-mentioned object, the present invention according to claim 1 is provided in parallel with the cutter 8, and is provided in parallel with the hood 4 of the shield machine 1 and the collapsing prevention wall 21 that can contact the back surface of the cutter 8. The collapse prevention body 20 formed by coupling the provided peripheral wall collapse prevention rod 22 at a substantially right angle is installed inside the hood 4 in combination with an arc shape or an annular shape that can cover at least the upper half of the face 17. A flexible wall is provided in the vicinity of the mating surfaces of the collapse prevention bodies 20, 20 adjacent in the circumferential direction, and each collapse prevention body 20 is connected to the front surface side of the partition wall 3 of the shield machine 1 and the back surface of the cutter 8. An anti-collapse agent is connected to the jack 23 for movement operation so as to be able to reciprocate between them, and into the area surrounded by the face 17 and the anti-collapse wall 21 through the inside of the rod 24 pushed and pulled by the jack 23 for movement operation. An injection tube 28 for injecting And, characterized in that.

The present invention according to claim 2 is characterized in that the flexible wall is configured by a flexible wire brush 29 in the circumferential direction on the face surface side on the inner surface of the peripheral wall collapse prevention rod 22 .

According to a third aspect of the present invention, the flexible wall is configured by laminating the rubber plate 30, the wire brush 29 or the rubber plate 30 and the wire brush 29 that are installed in the circumferential direction at a position in contact with the face surface. It is characterized by that .

  In the present invention, when there is a risk of collapsing the face during shield excavation, and when the cutter 8 is stopped in a state where the position of the bias of the cutter 8 is moved to the lower end of the cross-sectional shape of the shield machine, the shield machine 1 Each of the collapse prevention bodies 20 combined in an arc shape or an annular shape capable of covering at least the upper half of the face 17 inside the hood 4 of the hood 4 is moved to the front side of the partition wall 3 of the shield machine 1 by a moving operation jack 23. To the back of the cutter 8 and place it. The arcuate or annular collapse prevention body 20 placed on the back side of the cutter 8 prevents the loss of muddy water pressure acting on the face 17 and stabilizes the face 17. Next, a collapsing prevention aid is injected from the injection tube 28 into the area surrounded by the face 17 and the collapsing prevention wall 21 through the inside of the rod 24 fitted in the moving operation jack 23. Prevent collapse. Thus, according to the present invention, the face 17 is stabilized by the anti-collapse body 20 placed on the back surface of the cutter 8 and injected into the area surrounded by the face 17 and the anti-collapse wall 21. In combination with preventing the collapse of the face 17 by the collapsing prevention aid, there is a risk of the face collapsing during the shield excavation, and the position of the bias of the cutter 8 is moved to the lower end of the cross-sectional shape of the shield machine In any of the cases where the cutter 8 is stopped in the state of being made, there is an effect capable of accurately preventing the face 17 from collapsing.

  In the present invention, a flexible wall is provided in the vicinity of the mating surfaces of the collapse preventing bodies 20 and 20 adjacent to each other in the circumferential direction, and the collapse preventing body 20 is placed in an arc shape or an annular shape directly on the rear surface of the cutter 8. When preventing the loss of muddy water pressure acting on 17, the flexible wall can prevent the muddy water from flowing out from the mating surfaces of the collapse preventing bodies 20, 20 adjacent in the circumferential direction. There is an effect that can be accurately prevented.

  Embodiments of the present invention will be described below with reference to the drawings.

1 to 5 show Embodiment 1 of the present invention. FIG. 1 is a longitudinal side view of a part of a shield machine in a state where a collapse prevention body is stopped on the front side of a partition wall of the shield machine, and FIG. FIG. 3 is an enlarged longitudinal sectional side view of the collapse prevention body , FIG. 4 is an enlarged front view of the collapse prevention body, and FIG. 5 is a state in which the collapse prevention body is placed at the operating position on the back side of the cutter. FIG.

  The shield machine 1 shown in FIGS. 1 and 2 is drivingly connected to a shield outer cylinder 2, a partition wall 3, a hood 4, four cutter driving devices 5 in this embodiment, and each cutter driving device 5. Surrounded by four crank portions 6, a cutter 8 commonly attached to the four crank portions 6 via a crankshaft 7 provided in each crank portion 6, a partition wall 3, a hood 4, and a cutter 8. A face chamber 11, an agitator 14 disposed in the face chamber 11 and driven and connected to an agitator drive motor 12 via a rotary shaft 13, and a drainage water pipe 15 installed with the inlet facing the face chamber 11. , And a mud supply pipe 16 installed so as to be able to supply mud water to the face chamber 11 by bending the tip part into an elbow shape. This shield machine 1 is further provided with a shield jack, a backfilling material injection means, a tail seal and the like, but these members are omitted in the drawing.

  As can be seen from FIG. 1, the cutter 8 is formed to have an outer diameter smaller than the inner diameter of the hood 4. In addition, a number of cutter bits 9 are provided on the front surface of the cutter 8, and a plurality of stirring plates 10 are provided on the back surface. The cutter 8 is commonly attached to four crankshafts 7 provided at an eccentric distance e to four crank portions 6 provided at the corners of the rectangular locus. As the drive device 5 is driven in the same direction, it is rotated through parallel link motions by the four crank portions 6, and the ground is removed by the multiple cutter bits 9 and the cross-sectional shapes of the shield outer cylinder 2 and the hood 4. The excavated soil and muddy water are agitated by a plurality of agitation plates 10 by excavating into substantially the same shape.

  During the excavation of the natural ground, mud pressure is applied to the face surface so that the stability of the face 17 is maintained.

  By the way, as described above, the shape of the cutter 8 in this eccentric multi-axis cutter rotation type mud shield machine is formed to have a small diameter as much as twice the cutter rotation radius as compared with the shield outer diameter. Therefore, an opening 19 is generated between the outer periphery 18 of the shield and the outer periphery of the cutter 8 excavated in substantially the same shape as the cross-sectional shape of the hood 4. The collapse of the face 17 often occurs near the top end of the face 17. In addition, when the shield excavation is stopped for a long time, the cutter 8 is stopped at the lower end of the cross-sectional shape of the shield machine 1 so that no eccentric rotational torque is generated. The opening 19 is generated in the part.

  In view of these circumstances, in the first embodiment, the face-breaking collapse prevention body 20 is installed inside the hood 4 of the shield machine 1.

  The collapse preventing body 20 is formed by joining a collapse preventing wall 21 provided in parallel with the cutter 8 and a peripheral wall collapse preventing rod 22 provided in parallel with the hood 4 by means such as welding. Has been. A plurality of collapse prevention bodies 20 are combined in an arc shape that can cover at least the upper half of the face 17, and are installed inside the hood 4. A plurality of collapse prevention bodies 20 may be combined in an annular shape.

  Each collapse preventing body 20 is connected to a moving operation jack 23 via a rod 24. As shown in FIG. 1, the moving operation jack 23 is swingably attached to a bracket 25 fixed inside the shield outer cylinder 2 via a pin 26. The moving operation jack 23 is configured to reciprocate the collapse preventing body 20 between the front surface side of the partition wall 3 and the back surface of the cutter 8 via the rod 24.

An injection passage 27 for an anti-collapse agent is formed inside the rod 24 pushed and pulled by the moving operation jack 23. The injection passage 27 is connected with an injection pipe 28 for an anti-collapse agent, and is formed inside the rod 24 in an area surrounded by the face 17 and the anti-collapse wall 21 when the anti-collapse body 20 is operated. The collapsing prevention aid is injected through the injection passage 27 formed.

  A flexible wall is provided in the vicinity of the mating surfaces of the collapse preventing bodies 20 and 20 adjacent to each other in the circumferential direction in a row in which the plurality of collapse preventing bodies 20 are combined in an arc shape or an annular shape. In the first embodiment, the flexible wall is configured by attaching a wire brush 29 to the inner surface of the peripheral wall collapse preventing rod 22. The wire brush 29 is attached to the base material 29 ′ by being implanted into the base material 29 ′ and bonded or welded to the inner surface of the peripheral wall collapse prevention ridge 22. And the said wire brush 29 which is a flexible wall prevents the outflow of muddy water from the mating face of the collapse prevention bodies 20 and 20 adjacent to the circumference direction at the time of the effect | action of the collapse prevention body cage | basket 20.

  In the muddy water shield machine configured as described above, the collapse prevention body 20 is stopped at a position on the front side of the partition wall 3 of the shield machine 1 as shown in FIG.

  Therefore, when there is a risk of face collapse during shield excavation, or when the cutter 8 is stopped in a state where the offset position of the cutter 8 is moved to the lower end of the cross-sectional shape of the shield machine 1, The collapse prevention body 20 is moved from the front surface side of the partition wall 3 to the back surface of the cutter 8 by the moving operation jack 23 as shown in FIG. In this way, the arc-shaped or annular collapse prevention body 20 formed by moving each collapse prevention body 20 to the back side of the cutter 8 covers the muddy water pressure acting on the face 17 so as not to be lost. The face 17 is stabilized.

  Further, as described above, each collapse prevention body 20 is formed on a tubular body connected from the injection tube 28 to the rod 24 fitted in the moving operation jack 23 in a state in which each collapse prevention body 20 is placed on the back surface of the cutter 8. The collapsing prevention aid is injected into the area surrounded by the face 17 and the anti-collapse wall 21 through the injection passage 27, thereby preventing the face 17 from collapsing. For example, high-density mud is used as the anti-collapse agent. In addition, the specific gravity of the muddy water at the time of excavation is about 1.05-1.20, and the specific gravity of the high density muddy water is about 1.20 more than this and about 1.40 less than about 1.40.

  As described above, there is a risk of face collapse during shield excavation, and a case where the cutter 8 is stopped in a state of being moved to the lower end of the cross-sectional shape of the shield machine 1 in order to stop the shield excavation for a long time. However, the face 17 can be stabilized and collapse can be prevented accurately.

  Furthermore, in this embodiment, a flexible wall configured by attaching a wire brush 29 to the inner surface of the peripheral wall collapse prevention rod 22 is provided in the vicinity of the mating surface of the collapse prevention bodies 20 and 20 adjacent in the circumferential direction. Since the wire brush 29 can prevent the muddy water from flowing out from the mating surfaces of the collapse preventing bodies 20, 20 adjacent in the circumferential direction with the prevention body 20 placed on the back surface of the cutter 8, the face 17 Can be more reliably prevented. Note that the collapse prevention body 20 is pulled back to the front surface of the partition wall 3 by the moving operation jack 23 before the resuming of the excavation from the stop. This allows the cutter to turn. The anti-collapse agent (high-concentration mud) is mixed with the mud in the chamber by the rotation of the cutter and diluted, and the mud concentration is adjusted together with the circulating mud in the ground mud treatment facility (not shown). As recycled.

  FIG. 6 shows a second embodiment of the present invention, and is a longitudinal side view of a state in which the collapse prevention body is placed at the working position on the back side of the cutter.

  In Example 2 shown in FIG. 6, the rubber plate 30 of the flexible wall is installed in the circumferential direction at a position in contact with the face surface. A wire brush (not shown) having the same configuration can be used instead of the rubber plate. It is also preferable to overlap the rubber plate and the wire brush in layers. In this Example 2, the disintegration prevention auxiliary agent (high concentration mud water) in the case of Example 1 directly touches the face part, is diluted and diffused, and the effect of preventing this can be prevented when the disintegration preventive effect decreases. is there.

  The rubber plate 30 has flexibility, and is formed into a fin shape by being pressed by a moving operation jack and hitting a cutter.

  In the flexible wall of this embodiment, as can be seen from FIG. 6, the rubber plate 30 comes into surface contact with the end face of the cutter 8 when the collapse preventing body 20 is placed on the immediate rear surface of the cutter 8. The loss of muddy water from the mating surfaces of the collapse preventing bodies 20 and 20 adjacent to each other can be better prevented, and therefore the collapse of the face 17 can be prevented even better.

  Other configurations and operations of the second embodiment are the same as those of the first embodiment.

BRIEF DESCRIPTION OF THE DRAWINGS It is Example 1 of this invention, Comprising: It is a vertical side view of the part of a shield machine in the state which stopped the collapse prevention body to the front side of the partition of a shield machine. It is the sectional view on the AA line of FIG. It is an expansion vertical side view of the collapse prevention body in Example 1. FIG. It is an enlarged front view of the collapse prevention body in Example 1. FIG. It is a vertical side view of the state which fixed the collapse prevention body in Example 1 in the action position of the direct back surface of a cutter. FIG. 9 is a longitudinal side view showing a second embodiment of the present invention in a state in which a collapse preventing body is placed at an action position on the direct back surface of a cutter. It is the schematic diagram which looked at the side of the shield machine from the collapse of the face in the muddy water shield machine. It is the schematic diagram which looked at the collapse of the face from the front side of the shield machine.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Shield machine 2 Shield outer cylinder 3 Bulkhead 4 Hood 5 Cutter drive device 6 Crank part 7 Crankshaft 8 Cutter 17 Face 20 Face collapsing prevention body 21 Collapsing prevention wall 22 Circumferential wall collapsing prevention rod 23 Jack for operation prevention of collapsing prevention body 24 Rod inserted in jack for moving operation 27 Injection passage for collapsing prevention aid 28 Same injection tube 29 Wire brush as flexible wall 30 Rubber plate constituting flexible wall

Claims (3)

In a muddy water shield machine of the type that rotates the cutter (8) by an eccentric multi-axis mechanism to excavate natural ground, propel the shield machine (1), and prevent the face (17) from collapsing by muddy water pressure,
A collapse prevention wall (21) provided in parallel with the cutter (8) and capable of contacting the back surface of the cutter (8), and a peripheral wall collapse prevention provided in parallel with the hood (4) of the shield machine (1) A collapsible prevention body (20) formed by joining a ridge (22) at a substantially right angle is combined with the inside of the hood (4) in an arc shape or an annular shape capable of covering at least the upper half of the face (17). Installed,
In the vicinity of the mating surface of the collapse prevention bodies (20) and (20) adjacent in the circumferential direction, a flexible wall is provided,
Each collapse prevention body (20) is connected to a jack (23) for movement operation so as to be reciprocally movable between the front side of the partition wall (3) of the shield machine (1) and the back side of the cutter (8),
An injection tube (28) for injecting an anti-collapse agent into an area surrounded by the face (17) and the anti-collapse wall (21) through the inside of the rod (24) pushed and pulled by the moving operation jack (23). Provided,
A muddy water shield machine characterized by that. The flexible wall is configured with a flexible wire brush (29) in the circumferential direction on the face side on the inner surface of the peripheral wall collapse prevention ridge (22),
The muddy water shield machine according to claim 1 . The flexible wall is configured by laminating a rubber plate (30), a wire brush (29), or a rubber plate (30) and a wire brush (29) installed in a circumferential direction at a position in contact with the face surface. ,
The muddy water shielding machine according to claim 2.

Images