JP3886862B2 - Ground improvement equipment in tunnel construction. - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention is suitable for tunnel construction using a tunnel excavator. Can The present invention relates to a ground improvement device.
[0002]
[Prior art]
In tunnel construction using a tunnel excavator, when the ground is easy to collapse or when performing sharp curve construction, the soil in the vicinity of the excavator is ground by chemical injection to prevent the fall of the face. Improvements need to be made. Here, there is no problem as long as the medicine can be injected from the ground, but the medicine must be injected from within the excavator because it cannot be poured from the ground in the case of restrictions on ground traffic securing or large-scale construction. As a ground improvement device for injecting a drug from the inside of an excavator, one shown in FIG. 13 is known.
[0003]
As shown in the figure, this ground improvement device is provided with a rotating partition wall c in a fixed partition wall b that divides the inside and outside of a cylindrical shield frame a of a tunnel excavator (shield machine), and an inclined hollow tube d in the rotating partition wall c. And an injector f for injecting the drug forward into the inclined hollow tube d. According to this ground improvement device, the rotating partition c is rotated by the motor g, so that the injector f swings around the rotation center axis of the cutter e in a conical shape, so that the medicine is injected over a wide range in front of the face. it can.
[0004]
[Problems to be solved by the invention]
However, the ground improvement device has a problem in that it cannot be applied to a tunnel excavator of a type that does not have the rotating partition c (for example, the type shown in FIG. 1 or the like) because the rotating partition c is essential for its configuration. That is, in the type of FIG. 1, a rotating ring is pivotally supported on the outer peripheral portion of the fixed partition wall, and a dome-shaped cutter is attached to the rotating ring, and therefore there is no rotating partition wall c to which the injector f is to be attached. For this reason, the above-mentioned ground improvement apparatus which makes the injection device f attached to the rotary partition c swing in a conical shape with the rotation of the rotary partition c and makes the injection range of the medicine wide is not applicable.
[0005]
Further, as shown in FIG. 14, the ground improvement device has a problem that it is difficult to properly inject a medicine into the inside of the curve when performing a sharp curve construction. That is, at the time of sharp curve construction, it is necessary to improve the ground on both sides of the curve within a range of a predetermined width L, but increasing the inclination angle θ with respect to the cutter rotation center line of the injector f is limited due to the mechanism of the apparatus. Therefore, although the drug can be injected into the predetermined width L outside the curve, the drug cannot be injected into the predetermined width L inside the curve.
[0006]
In the ground improvement device, as shown in FIG. 13, an injector f is attached to the rotary partition c, and in the vicinity thereof, a sand transport device (not shown) for transporting the sand in the cutter chamber h into the mine. (Screw conveyor, feed / drain mud pipe, etc.) are placed and the motor g is also present, so only a narrow space is left, and it is actually difficult to install (especially difficult in the case of a small diameter). . In addition, work efficiency is poor because an operator must perform chemical injection work in a narrow space.
[0007]
The purpose of the present invention created in consideration of the above circumstances can be applied regardless of the cutter structure of the excavator, can properly inject the medicine into the inside of the curve at the time of sharp curve construction, and secures a wide working space For tunnel construction Can It is to provide a ground improvement device.
[0008]
[Means for Solving the Problems]
To achieve the above objective Book Ground improvement in tunnel construction related to the invention apparatus Is the existing segment located behind the tunnel excavator For a ground improvement agent that is provided with a projecting member that protrudes outward in the radial direction, and that extends through the segment from the inner side to the outer side and extends obliquely forward to the tunnel excavator side when projecting. Injection tube Provided Is.
[0009]
According to the present invention, since the drug injection is performed by extending the injection pipe obliquely forward from the existing segment behind the excavator to the excavator side, the drug injection can be performed regardless of the cutter structure of the excavator. That is, the present invention can also be applied to a type of excavator that does not include a rotating bulkhead. In addition, since it is easy to increase the oblique angle of the injection tube with respect to the tunnel center line, when carrying out a sharp curve construction, the above angle is increased in the right-angle direction, so that the drug can be properly applied to the inside of the curve. Can be injected. Further, since the portion where the existing segment is located is away from the excavator, a large work space can be secured.
[0011]
Also The projecting member protrudes outward in the radial direction of the existing segment, and since the projecting projecting member penetrates the injection pipe for injecting the drug and extends obliquely forward to the excavator side, the projecting member is projected. The oblique angle with respect to the tunnel center line of the injection tube can be reduced by that amount. Therefore, a chemical | medical agent can be inject | poured into the earth and sand in the vicinity of an excavator.
[0012]
In addition, the intruding member may have a swinging member in which a communication path communicating between the inside and the outside of the tunnel is formed, and the injection pipe may be penetrated through the communication path of the swinging member. In this way, by adjusting the swing angle of the swing member, the oblique angle with respect to the tunnel center line of the injection tube can be arbitrarily changed.
[0013]
Moreover, the communicating path of the swinging member may also serve as a soil removal path for discharging the earth and sand of the side natural ground when the projecting member protrudes. In this way, it is not necessary to separately provide a soil removal passage for discharging the earth and sand of the side ground in the intruding member, which leads to downsizing and cost reduction of the device.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
An embodiment of the present invention will be described with reference to the accompanying drawings.
[0015]
FIG. 1 is a cross-sectional plan view of a shield machine equipped with a ground improvement device according to the present embodiment, FIG. 2 is a cross-sectional view before the operation of the ground improvement device, and FIG. 3 is a cross-sectional view after the operation of the ground improvement device. It is a figure (III-III sectional view taken on the line of FIG. 1).
[0016]
As shown in FIG. 1, this shield machine 1 (tunnel excavator) is a so-called folded shield in which a cylindrical front trunk 2 and a rear trunk 3 constituting a shield frame are connected via a middle jack 4. It is suitable for sharp curve construction. However, since the ground improvement device according to the present embodiment is not attached to the excavation machine 1, it is not limited to the bent shield and can also be applied to a normal shield machine.
[0017]
The front barrel 2 is provided with a fixed partition wall 5 that partitions the interior back and forth. A rotating ring 6 is pivotally supported on the outer periphery of the fixed partition wall 5, and a dome-shaped cutter head 7 is attached to the rotating ring 6. The cutter head 7 is attached with a roller cutter and a bit (not shown) for rock cutting. However, since the ground improvement apparatus according to the present embodiment is not attached to the excavator 1, it is not limited to such a cutter, and can be applied regardless of the cutter type.
[0018]
An internal gear 8 is attached to the rotating ring 6. A pinion 10 provided on the rotating shaft of the motor 9 is meshed with the internal gear 8. According to this configuration, by driving the motor 9, the cutter head 7 is rotated, and the face (bedrock, hard ground, etc.) is excavated by the roller cutter and the bit. The excavated earth and sand are once taken into the cutter chamber 11 in front of the partition wall 5 and transferred into the mine by a conveying device such as a screw conveyor 12.
[0019]
A propulsion jack 13 is provided around the inner peripheral surface of the rear trunk 3. The propulsion jack 13 takes the reaction force on the existing segment 14 and advances the excavator 1. The segment 14 is assembled in a ring shape inside the rear cylinder 3 by an unillustrated erector (segment assembly device) provided in the rear cylinder 3, and is pushed backward relatively by the propulsion jack 13. In addition, a tail seal 15 is provided at the rear end of the rear barrel 3 to stop the gap with the existing segment 14.
[0020]
As shown in FIG. 1, the ground improvement device 20 according to the present embodiment is attached to the special segment 14a regardless of the shield machine 1 described above. That is, the predetermined member 14a is provided with a protruding member 21 that forms a part of the ground improvement device 20 so as to be protruded and protruded radially outward. As shown in FIGS. 2, 3, and 4, the intruding member 21 includes an outer cylinder 23 provided with a flange 22, an inner cylinder 25 with a flange 24 slidably attached to the outer cylinder 23, A partition member 26 that partitions the inside of the cylinder 25 and a swing member 27 that is swingably attached to the partition member 26 are provided.
[0021]
The swinging member 27 includes a sphere 28, a rod body 29 provided on the sphere 28, a communication passage 30 formed through the sphere 28 and the rod body 29, and a valve body 31 that opens and closes the communication passage 30. On the other hand, a spherical seat 32 is formed in the partition member 26 so as to communicate the inside and outside of the tunnel. A spherical body 28 of the swing member 27 is attached to the spherical seat 32, and the swing member 27 can swing freely. This also allows the communication path 30 to communicate between the inside and outside of the tunnel.
[0022]
As shown in FIGS. 2 and 3, the projecting member 21 has an outer cylinder 23 slidably mounted in a mounting hole 33 opened in the special segment 14 a, and the outer cylinder 23 is attached to the mounting hole 33. By sliding and sliding the inner cylinder 25 with respect to the outer cylinder 23, the outer cylinder 23 appears and disappears radially outward from the outer peripheral surface of the segment 14a. At this time, the flanges 22 and 24 serve as stoppers that regulate the protruding positions.
[0023]
Further, a seal (not shown) is provided on the inner peripheral surface of the mounting hole 33 to stop water between the outer tube 23 and the inner peripheral surface of the outer tube 23 is stopped between the inner tube 25 and the inner tube 25. A water seal (not shown) is provided. The mounting hole 33 is provided in a hole block 34 attached to the segment 14a with a bolt or the like.
[0024]
Details of the retracting member 21 will be described with reference to FIGS.
[0025]
As shown in FIG. 4, the outer cylinder 23 is covered with the side surface of the mounting hole 33 when the tip thereof is substantially flush with the outer peripheral surface of the segment 14a, and the tip of the segment 14a is shown in FIG. An outer hole 35 is formed at a position where it is exposed to the side natural ground when projected to the outer peripheral side. Further, as shown in FIG. 6, the outer cylinder 23 is formed with a U-shaped outer groove 36 into which the swing member 27 is fitted when the swing member 27 is rotated.
[0026]
On the other hand, an inner hole 37 is formed in the inner cylinder 25 at a position where it communicates with the outer hole 35 of the outer cylinder 23 when the tip of the inner cylinder 25 protrudes to the outer peripheral side of the segment 14a as shown in FIG. In addition, a U-shaped inner groove 38 is formed in the inner cylinder 23 at a position overlapping with the outer groove 36 of the outer cylinder 23 at this time. Therefore, as shown in FIG. 6, the swinging member 27 is fitted into the overlapped inner groove 38 and outer groove 36.
[0027]
The inner hole 37 and the inner groove 38 are partitioned by a partition member 26 disposed obliquely in the inner cylinder 25, the inner hole 37 is located outside the well, and the inner groove 38 is located inside the well. Here, as shown in FIG. 4, when the inner cylinder 25 and the outer cylinder 23 are drawn, a part of the inner hole 37 is wrapped in the outer hole 35, so that the earth and sand water in the side natural ground is Although it penetrates to the outer hole 35 through the hole 37, since the outer hole 35 is covered with the side surface of the mounting hole 33 at this time, the earth and sand water of the side natural ground does not enter the pit.
[0028]
Further, as shown in FIGS. 5 and 6, when the swinging member 27 rotates and engages with the inner groove 38 and the outer groove 36 in the vicinity of the inner groove 38 and the outer groove 36, In order to avoid interference with the member 27, a detachable block 39 is detachably attached. The detachable block 39 exhibits a function of guiding the outer cylinder 23 from FIGS. 4 to 5, but can be omitted from the beginning.
[0029]
As shown in FIGS. 2 and 4, the projecting member 21 normally includes a stepped bolt 40 or the like that passes through the flange 24 of the inner cylinder 25 and the flange 22 of the outer cylinder 23 and is screwed into the hole block 34. The tips of the inner cylinder 25 and the outer cylinder 23 are fixed by the spacer so that they are substantially flush with the outer peripheral surface of the segment 14a. As shown in FIGS. 3 and 5, the stepped bolt 40 is removed when the inner cylinder 25 and the outer cylinder 23 protrude from the outer peripheral surface of the segment 14a.
[0030]
The inner cylinder 25 and the outer cylinder 23 are pushed out from the state of FIG. 2 to the outer peripheral side of the segment 14a by the extrusion device 41 shown in FIGS. 1 to 3, as shown in FIG. The extrusion device 41 is arranged at the center of the tunnel approximately on the support column 43, a base 42 that is movably seated on the bottom of the tunnel, a support column 43 that extends from the base 42 toward the center (upward) of the tunnel. The rotating block 45 is rotatably attached via the pin 44, and the turning arm 46 is mounted on the rotating block 45 so as to be slidable in the tunnel radial direction.
[0031]
As shown in FIGS. 2 and 3, a pressing portion 47 that contacts the flange 24 of the inner cylinder 25 is provided at one end of the turning arm 46, and the other end of the turning arm 46 is shown in FIG. 1. A branch body 48 is provided so as to straddle the inner cylinder 25 positioned 180 degrees opposite to the inner cylinder 25 to be extruded. The branch body 48 is formed by arranging Y-shaped members formed in a Y-shape in the longitudinal direction of the tunnel as shown in FIG. 1 in two stages as shown in FIGS. Is provided with a jack 49 that contacts the segment 14.
[0032]
According to this configuration, by extending the jack 49 from the state of FIG. 2, as shown in FIG. 3, the turning arm 46 moves with respect to the rotary block 45, and the inner cylinder 25 and the outer cylinder 23 are pressed against the pressing portion 47. Pressed to protrude. Thereafter, the jack 49 is contracted, the relative position of the turning arm 46 with respect to the rotating block 45 is returned to the state shown in FIG. 2, and the turning arm 46 is appropriately rotated around the pin 44. The outer cylinder 23 can be protruded. In addition, since the branch body 48 is formed so that it may straddle each inner cylinder 25 (intrusion member 21) back and forth at the time of rotation of the turning arm 46, rotation of the turning arm 46 is not hindered.
[0033]
The operation of the present embodiment having the above configuration will be described.
[0034]
In tunnel construction using the shield machine 1, in certain cases such as soil quality or sharp curve construction, soil improvement in front of the machine 1 is improved by chemical injection to prevent the fall of the face. There is a need to do. In this case, first, as shown in FIG. 1, the special segment 14 a equipped with the protruding and retracting member 21 is disposed at a point away from the shield machine 1 by a predetermined distance. This arrangement is performed as follows.
[0035]
First, the special segment 14a in which the mounting hole 33 is opened is assembled in a ring shape by an erector inward of the rear barrel 3. Next, the outer cylinder 23 is inserted into the mounting hole 33 of each segment 14 a, and the inner cylinder 25 is inserted into the outer cylinder 23. A partition member 26 is attached to the inner cylinder 25, and a swing member 27 is attached to the partition member 26. Then, as shown in FIGS. 2 and 4, the inner cylinder 25 and the outer cylinder 23 are fixed to the special segment 14 a by the stepped bolt 40. Thereby, the water stop of the part of the mounting hole 33 is completed. Thereafter, the special segment 14a is fed backward by the propulsion jack 13 to the position shown in FIG.
[0036]
Next, as shown in FIG. 1 and FIG. 2, the extrusion device 41 is set in the tunnel, and the stepped bolt 40 shown in FIG. 2 is removed. Then, as shown in FIG. 3, the inner cylinder 25 and the outer cylinder 23 are pushed out by the jack 49 of the extrusion device 41. As a result, the inner cylinder 25 and the outer cylinder 23 protrude from the outer peripheral surface of the segment 14a as shown in FIG. 5 while the distal ends thereof protrude from the outer peripheral surface of the segment 14a as shown in FIG. It becomes a state.
[0037]
Here, if the valve body 31 of the swinging member 27 is opened from FIG. 4 to FIG. 5, the earth and sand of the side ground will be discharged into the mine through the communication passage 30 formed inside the swinging member 27. Is done. At this time, the communication path 30 functions as a soil discharge path. In this case, it is not necessary to separately provide a soil removal passage for discharging the earth and sand from the side ground in the partition member 26, which leads to downsizing and cost reduction of the apparatus. After the earthing, the valve body 31 is closed.
[0038]
Prior to projecting the inner cylinder 25 and the outer cylinder 23 as shown in FIGS. 4 to 5, the valve body 31 is opened to inject water, a mud-producing agent or the like from the inside of the mine to the side ground, and project it. Part of the earth and sand may be fluidized. At this time, the communication path 30 functions as a water injection path. If it carries out like this, since a side part ground will be fluidized, the earth removal property will improve, and the burden of the operating force of the jack 49 of the extrusion apparatus 41 will become small.
[0039]
Thus, when the inner cylinder 25 and the outer cylinder 23 are projected, as shown in FIG. 5, the outer hole 35 and the inner hole 37 overlap, and the outer groove 36 and the inner groove 38 overlap. Thereafter, the detachable block 39 is removed, and the swinging member 27 is rotated as shown in FIG. 6, and the rod body 29 of the swinging member 27 is engaged with the outer groove 36 and the inner groove 38 that are wrapped. The outlet of the communication passage 30 opened in the spherical body is opposed to the inner hole 37 and the outer hole 35 which are wrapped.
[0040]
At this time, since the partition member 26 that supports the swinging member 27 protrudes radially outward from the position of FIG. 4, the pivoting fulcrum of the swinging member 27 is shifted to the side ground side by the amount of the protrusion. Accordingly, in combination with the rod body 29 of the swinging member 27 fitting into the outer groove 36 and the inner groove 38, the oblique angle θ (see FIG. 1) of the swinging member 27 with respect to the tunnel center line is reduced. it can.
[0041]
Thereafter, the valve body 31 is opened, and as shown in FIG. 7, the injection pipe 50 is inserted into the communication passage 30 of the swing member 27, and obliquely forward through the outer hole 35 of the outer cylinder 23 and the inner hole 35 of the inner cylinder 25. Stretch to. Here, since the oblique angle θ with respect to the tunnel center line of the swinging member 27 can be reduced as described above, the drug injection angle θ (see FIG. 1) with respect to the tunnel axis of the injection tube 50 can also be reduced.
[0042]
Insertion and extension of the injection tube 50 into the side ground are performed by a known percussion drill, midget drill, or the like. The percussion drill grips the base of the injection tube 50 and vibrates it in the axial direction, and penetrates the injection tube 50 into the ground. The midget drill grips the base of the injection tube 50 and rotates it around the axis. However, the injection tube 50 penetrates into the natural ground. Each of the drills is extended by adding an injection tube 50 having a predetermined length.
[0043]
If the injection pipe 50 is extended to the front of the shield machine 1 with these drills as shown in FIG. 9, the ground improvement agent (concrete or the like) is sprayed while the injection pipe 50 is pulled out, and the ground is columnar. The ground improvement area 51 is generated. Thus, since the injection pipe 50 is extended obliquely forward from the existing special segment 14a (see FIGS. 1 to 3) behind the excavator 1 to the excavator 1 side, the cutter structure of the excavator 1 is provided. Drug injection can be performed completely independently of the above. In other words, it can be applied to an excavator of a type that does not have a rotating bulkhead, and can cope with any soil quality.
[0044]
Further, as described above, the rotation center (position of the sphere 28) of the swing member 27 is moved outward from the position of FIG. 4 and the swing member 27 is fitted into the outer groove 36 and the inner groove 38. The chemical injection angle θ with respect to the tunnel axis of the injection pipe 50 can be reduced, and the chemical can be injected into the earth and sand near the excavator 1. Therefore, the ground in the vicinity of the excavator 1 can be improved. Moreover, the ground improvement area 51 by chemical injection can be changed by changing the said chemical injection angle (theta). Moreover, since the part in which the segment 14a is located is away from the excavator 1, a large work space can be secured. Therefore, it can be realized with the small-diameter excavator 1, and the workability and safety for chemical injection are improved.
[0045]
Then, the above operation is performed for all the outer cylinder protruding and retracting members 21 of the same ring shown in FIGS. 2 and 3, and as shown in FIG. 10, the cylindrical ground improvement region 51 is surrounded on the left and right upper sides of the shield machine 1. To generate a gate type. Thereafter, as shown in FIG. 9, the shield machine 1 is moved forward by a predetermined distance, and the drug is injected into the portal shape by the same procedure from the special segment 14 a arranged in the forward direction in the same manner. Generate. At this time, as shown in FIG. 10, it is preferable to perform the drug injection while shifting the phase from the previously performed drug injection region.
[0046]
After such a chemical injection operation, as shown in FIG. 8, the solidifying agent 54 is applied to the tail voids (between the shield frame 3 and the existing segment 14) and the side ground in the vicinity thereof from the segments 14 and the like before and after the special segment 14a. Fill with concrete. Then, after the solidifying agent 54 is solidified, the outer cylinder 23 and the members 25, 26, 27 and the like inside the mounting hole 33 are extracted, and a lid 53 is fitted into the mounting hole 33 and fixed. Thereby, the retractable member 21 (the inner cylinder 25, the outer cylinder 23, the partition member 26, the swing member 27, etc.) can be reused.
[0047]
Moreover, as shown in FIG. 9, when carrying out sharp curve construction using the shield machine 1, it is necessary to improve the ground on the left and right sides of the curve within a predetermined width L. Although it is necessary to gradually increase the angle θ along with the excavation, a change to increase the angle θ is easy. This is because it is difficult to reduce the drug injection angle θ for the purpose of penetrating the drug injection tube 50 into and out of the segment 14 (see FIG. 1), but increasing the drug injection angle θ is shown in FIGS. This is because the inner hole 37 and the outer hole 35 shown in FIG. 7 can be easily enlarged by making them into elongated holes extending toward the side natural ground or by forming grooves into the tips of the inner and outer cylinders 23 and 25. Therefore, in this embodiment, as shown in FIG. 9, when carrying out a sharp curve construction, the ground can be reliably improved in the range of a predetermined width L on both the left and right sides of the curve.
[0048]
Another embodiment of the present invention is shown in FIGS.
[0049]
As shown in the figure, this embodiment is different from the previous embodiment only in the structure of the retracting member 21, and the other parts are the same as the previous embodiment. Therefore, only the changed retracting member 21a will be described. Description of this part is omitted.
[0050]
As shown in FIG. 11, a projecting and retracting member 21 a that forms a part of the ground improvement device is mounted on a predetermined special segment 14 a so as to be able to project and retract radially outward. The in / out member 21 a includes a cylinder 71 provided with a flange 70, a partition member 72 that partitions the inside of the cylinder 71, and a swing member 73 that is swingably attached to the partition member 72.
[0051]
The swinging member 73 includes a sphere 74, a rod body 75 provided on the sphere 74, a communication passage formed through the sphere 74 and the rod body 75, and a valve body 76 that opens and closes the communication passage. On the other hand, a spherical seat is formed in the partition member 72 so as to communicate the inside and outside of the tunnel. The spherical body 74 of the swinging member 73 is attached to the spherical seat so that the swinging member 73 can swing freely. This also allows the communication path to communicate between the inside and outside of the tunnel.
[0052]
On the other hand, the special segment 14 a is formed with a mounting hole 77 that communicates with the inside and outside of the special segment 14 a, and a guide cylinder 79 with a flange 78 is fixed to the mounting hole 77. The cylindrical body 71 is slidably mounted on the guide cylinder 79. The flanges 70 and 78 serve as stoppers when the cylinder 71 slides with respect to the guide cylinder 79. Further, a seal (not shown) for stopping water between the cylindrical body 71 is provided on the inner peripheral surface of the guide cylinder 79.
[0053]
As shown in FIG. 11, the cylindrical body 71 is covered with the inner peripheral surface of the guide cylinder 79 when the distal end is substantially flush with the outer peripheral surface of the segment 14a, and the distal end is segmented as shown in FIG. A hole 80 is formed at a position exposed to the side natural ground when projected to the outer peripheral side of 14a. Further, as shown in FIG. 12, the cylindrical body 71 is formed with a U-shaped inner groove (long hole) 81 into which the swing member 73 is fitted when the swing member 73 is rotated.
[0054]
On the other hand, in order to avoid interference with the injection tube 82 at the position where the outer hole 80 of the cylindrical body 71 faces when the cylindrical body 71 protrudes to the outer peripheral side of the segment 14a as shown in FIG. A recess 83 recessed in a slope shape is formed. In addition, a U-shaped outer groove 84 is formed in the guide tube 79 at a position overlapping the inner groove 81 at this time. Therefore, as shown in FIG. 12, the swinging swinging member 73 is fitted into the overlapping inner groove 81 and outer groove 84.
[0055]
The inner hole 80 and the inner groove 81 are partitioned by a partition member 72 disposed obliquely in the cylindrical body 71. The inner hole 80 is located outside the well and the inner groove 81 is located inside the well. Here, as shown in FIG. 11, when the cylinder 71 is retracted, the inner hole 80 is covered with the inner peripheral surface of the guide cylinder 79, so that the earth and sand water of the side natural ground enters the mine. There is nothing.
[0056]
As shown in FIG. 11, the cylindrical body 71 is normally segmented by a spacer such as a stepped bolt 85 screwed into the flange 70 of the cylindrical body 71 and the flange 78 of the guide cylinder 79. It is fixed in a state that is substantially flush with the outer peripheral surface of 14a. Then, as shown in FIG. 12, the stepped bolt 85 is removed when the cylindrical body 71 protrudes from the outer peripheral surface of the segment 14a.
[0057]
Also in this embodiment, the same operational effects as in the previous embodiment can be obtained. Moreover, since the structure of the intruding member 21a is simplified, the cost is reduced.
[0058]
【The invention's effect】
As explained above, in the tunnel construction according to the present invention. Can According to the ground improvement device, the following effects can be exhibited.
(1) Regardless of the cutter structure of the excavator, that is, for all soil types, the ground in the vicinity of the excavator can be improved in a wide range.
(2) When performing sharp curve construction, the ground can be properly improved inside the curve.
(3) A large work space can be secured.
[Brief description of the drawings]
FIG. 1 is a plan sectional view of a shield machine equipped with a ground improvement device according to an embodiment of the present invention.
FIG. 2 is a transverse sectional view before the operation of the ground improvement device.
FIG. 3 is a transverse cross-sectional view after operation of the ground improvement device (cross-sectional view taken along line III-III in FIG. 1).
FIG. 4 is a plan sectional view showing an operation process of the ground improvement device.
FIG. 5 is a plan sectional view showing an operation process of the ground improvement device.
FIG. 6 is a plan sectional view showing an operation process of the ground improvement device.
FIG. 7 is a plan sectional view showing an operation process of the ground improvement device.
FIG. 8 is a plan sectional view showing an operation process of the ground improvement device.
FIG. 9 is a plan sectional view showing a drug injection area during sharp curve construction by the ground improvement device.
10 is a cross-sectional view taken along line XX of FIG.
11A and 11B are explanatory views (before operation) showing another embodiment of the present invention, in which FIG. 11A is a plan sectional view and FIG. 11B is a transverse sectional view.
FIGS. 12A and 12B are explanatory views (after operation) showing another embodiment of the present invention, in which FIG. 11A is a plan sectional view and FIG. 11B is a transverse sectional view.
FIG. 13 is a cross-sectional plan view of a shield machine equipped with a conventional ground improvement device.
FIG. 14 is a plan sectional view showing a drug injection area during sharp curve construction by the ground improvement device.
[Explanation of symbols]
1 Tunnel excavator (Shield excavator)
14a Special segment as an existing segment
21 Extruding members
27 Swing member
30 communication path
50 Injection tube
θ Dosing angle

Claims (3)

The existing segment located at the rear of the tunnel excavator is provided with a projecting / retracting member that protrudes outward in the radial direction, and the projecting member is penetrated from the inside of the segment to the outside when projecting and extends obliquely forward to the tunnel excavator side. A ground improvement device in tunnel construction, characterized in that an injection pipe for a ground improvement agent is provided . 2. The ground improvement in tunnel construction according to claim 1, wherein the intruding member has a swinging member in which a communication path communicating between the inside and the outside of the tunnel is formed, and the injection pipe is penetrated through the communication path of the swinging member. apparatus. 3. The ground improvement device in tunnel construction according to claim 2, wherein the communication path of the swinging member also serves as a soil removal passage for removing soil from the side ground when the projecting member is protruded .

Images