JP2020079485A - Shield machine for connecting between tunnels and method of connecting between tunnels - Google Patents

Abstract

To provide a shield machine for connecting between tunnels and a method of connecting between tunnels, capable of safely and efficiently performing drilling while suppressing exposure of a natural ground, and also coping with changes in separation between tunnels.SOLUTION: A shield machine for connecting between tunnels includes: a shield body 2 provided with skin plates 21 covering four sides so as to be able to move forward, and having a partition wall 22 that divides the inside of the shield machine into a drilling chamber 2A and a lining assembling chamber for assembling steel panels in a front-rear direction Df; and a drilling machine 31 provided in the drilling chamber 2A, and capable of drilling a natural ground on a working face side from the drilling chamber 2A. The skin plate 21 includes a top plate 24, a bottom plate 25, and right and left side plates 26. An upper end and a lower end of each of the side plates 26 slidably contact an outer wall of one outer shell tunnel 13 in the front-rear direction Df in a liquid-tight state. The skin plate 21 is divided in a right-left direction Dv, and the divided skin plates 21 are provided slidably in the right-left direction Dv.SELECTED DRAWING: Figure 6

Description

  The present invention relates to a tunnel coupling shield machine and a tunnel coupling method.

  Conventionally, as a construction method of a branch confluence part forming a large-section underground cavity in a large-scale road tunnel, for example, as shown in Patent Document 1, a lining frame structure is provided in the outer shell part of the branch confluence part to be constructed. The work is done first, and then the inside of the lining frame structure is excavated.

  As such a lining structure, a plurality of outer shell tunnels are constructed at intervals in the circumferential direction by the shield construction method in the outer shell portion of the branch confluence, and then ground protection work is constructed by the freezing construction method, etc. There is known a structure constructed by cutting open between outer shell tunnels that are adjacent to each other in the circumferential direction, assembling a reinforcing bar and a formwork, and then placing concrete (for example, refer to Patent Document 2).

JP, 2011-184899, A JP, 2017-145571, A

  However, when cutting between outer shell tunnels like the conventional lining frame structure, ground protection work is performed by the freezing method etc. before excavation work, but the improved ground is exposed. Will be drilled in. The freezing method is a method that protects the ground safely and reliably, but in order to further enhance the safety in large-scale excavation, etc., support work such as support work and concrete spraying should be performed auxiliary during excavation. However, there is a problem that it takes time and effort. Further, in such a method, since the improved ground is exposed, there is room for improvement in terms of work safety.

  Further, there is also a construction method in which a protective protector surrounding the excavation area with a steel plate or the like is provided on the exposed portion of the improved ground, the excavation is performed without the protective protector, and the protective protector is sequentially moved forward. However, since the protective protector is set to a predetermined size, it is difficult to deal with the change in the distance between the tunnels.

  The present invention has been made in view of the above-mentioned problems, and it is possible to excavate safely and efficiently by suppressing the exposure of natural ground, and moreover, a tunnel connecting shield machine capable of coping with a change in separation between tunnels. , And a method for connecting between tunnels.

  In order to achieve the above-mentioned object, the inter-tunnel connection shield machine according to the present invention has an inter-tunnel structure for excavating between existing tunnels provided at intervals and for constructing a widening tunnel connecting the existing tunnels. A shield body having a partition wall, which is provided so as to be capable of advancing by covering four sides with skin plates, and which divides the inside of the shield machine into a drilling chamber and a lining assembly chamber for assembling a lining member in the front-rear direction, and The excavator is provided in the excavation chamber, and an excavator provided to excavate the ground on the face of the face from the excavation chamber, and the skin plate includes a top plate, a bottom plate, and left and right side plates, The upper and lower ends of the pair of left and right side plates are in liquid-tight contact with the outer wall of one of the existing tunnels so as to be slidable in the front-rear direction, and the skin plate is divided in the left-right direction. The divided skin plate is provided so as to be relatively slidable in the left-right direction.

  Further, the inter-tunnel connection method according to the present invention is a inter-tunnel connection method for constructing a widening tunnel that connects between the existing tunnels by using the above-described inter-tunnel connection shield machine, and among the side walls of the existing tunnel. Providing an opening in the excavation region located in front of the shield body, excavating the ground in the excavation region in front of the shield body by the excavation device, taking in excavated earth and sand into the excavation chamber, and separating the partition wall. Through the lining assembly chamber side, a step of advancing the shield body so as to be located in the excavated area, and the advancing of the shield body, the outer wall of the existing tunnel and the side plate So that they are not separated from each other, the step of sliding the left and right divided skin plates and the step of assembling the lining member in the lining assembly chamber are characterized.

In the present invention, it is possible to move forward while excavating between the existing tunnels by the excavating device in the shield body covered with skin plates on all four sides. Then, the width dimension of the shield body in the left-right direction can be changed by sliding the left and right skin plates in the direction of approaching and separating from each other. Therefore, even if the separation between the existing tunnels changes, the width of the shield body can be adjusted according to the separation, and the gap between the skin plate and the existing tunnel is always closed. You can dig in after protecting the ground.
As described above, according to the present invention, since it is possible to excavate the ground with minimal exposure of the ground between the existing tunnels, it is possible to prevent the ground from collapsing, and there is an advantage that the construction method is safe and reliable.

  Further, according to the present invention, since the upper end and the lower end of the skin plate are slidably contacted with the outer wall of one of the existing tunnels in the front-rear direction so as to be slidable in the front-rear direction, when the slide plate is moved in the front-rear direction. Moreover, it is possible to maintain a liquid-tight state with respect to the outer wall of the existing tunnel.

  Further, the tunnel connecting shield machine according to the present invention may be characterized in that the shield body is provided with a side protector capable of projecting forward from the side plate.

  In this case, by projecting the side protector forward before excavation, the existing tunnel and the ground in the excavation area can be blocked by the side protector, and the existing tunnel is opened to the ground in the excavation area. Things can be minimized. Therefore, the state in which the ground being excavated is exposed in the existing tunnel is minimized, so that the widening tunnel can be constructed by safe and reliable excavation work.

  Further, in the tunnel-to-tunnel connection shield machine according to the present invention, it is preferable that the shield body has a water blocking structure in which the entire shield body is in liquid-tight contact with an external ground and the existing tunnel.

  In this case, at the time of excavation, the state in which the entire shield body is in liquid-tight contact with the external ground and the existing tunnel to stop the water, including the part of the skin plate that is relatively slidable in the left-right direction, Can be maintained.

  Further, in the inter-tunnel connection method according to the present invention, the excavation direction by the inter-tunnel connection shield machine starts from a position where the separation between the existing tunnels is minimum, and advances toward a position where the separation is maximum. It may be done like this.

  In this case, it is possible to improve the construction efficiency by starting from a position where the separation between the existing tunnels is the minimum and proceeding toward the position where the separation is the maximum. In this case, since the inter-tunnel connecting shield machine can be assembled at the place where the distance between the existing tunnels is the smallest, the assembling work can be safely performed at the place around the assembling region where the ground condition is good.

  ADVANTAGE OF THE INVENTION According to the tunnel connection shield machine and tunnel connection method of the present invention, it is possible to excavate the ground safely, efficiently and efficiently, and to cope with changes in the distance between the tunnels.

It is a perspective view showing a construction state which carries out widening excavation between outer shell tunnels in an outer shell part of a branching and merging part by a connecting shield machine by an embodiment of the present invention. It is a perspective view which shows the outline construction state of a branch merge part. (A) is a cross-sectional view of a state in which an outer shell tunnel is under construction as seen from the tunnel direction, and (b) is a cross-sectional view of a branching and joining part constructed by excavating the inside of the lining frame structure of (a). . It is the perspective view which looked at the composition of a connection shield machine from the slanting front. It is a side view of the connection shield machine shown in FIG. It is the front view which looked at the connection shield machine from the front. It is the front view which looked at the connection shield machine from the back. It is the perspective view which looked at the connection shield machine from the slanting front, and is a figure showing the water stop structure. (A), (b) is a figure for demonstrating the construction process of a widening tunnel, and is a top view seen from the upper part. (A), (b) is a figure for demonstrating the construction process of the widening tunnel following FIG.9(b), and is a top view seen from above.

  Hereinafter, a tunnel coupling shield machine and an tunnel coupling method according to embodiments of the present invention will be described with reference to the drawings.

  As shown in FIG. 1, the tunnel coupling shield machine according to the present embodiment (hereinafter referred to as the coupling shield machine 1) is constructed in advance in the ground by a shield construction method, for example, in a large-scale road tunnel as shown in FIG. It is applied to the construction of the outer shell portion 10A of the branch merging portion 10 having a large cross section at the location where the ramp tunnel 12 merges and branches with respect to the main line tunnel 11.

  The connection shield machine 1 is for digging and widening between the outer shell tunnels 13, 13 (existing tunnels) provided at intervals in the outer shell portion 10A.

  As shown in FIG. 3A, the branching and merging portion 10 is a plurality of outer shell tunnels constructed so as to extend in parallel to the branching and merging portion 10 so as to surround the outside of the main tunnel 11 and the ramp tunnel 12. , 13 are formed as a part of the outer shell portion 10A. The branching and merging portion 10 has a substantially circular cross section, and excavates between the outer shell tunnels 13 and 13 that are adjacent to each other in the circumferential direction Z in a sectional view. A plurality of steel panels 70 (see FIG. 1) are connected and assembled so as to be continuous in the circumferential direction Z over an excavation region M (see FIGS. 9A and 9B) between them to form a lining frame structure 7. Then, it is constructed by excavating the inside of the lining frame structure 7.

  Here, in the present embodiment, in the outer shell portion 10A of the branch merging portion 10, the extending direction orthogonal to the vertical cross section of the branch merging portion 10 is referred to as a tunnel direction X, and passes through the center of the vertical cross section of the branch merging portion 10. The direction of rotation around the central axis is called the circumferential direction Z.

  The plurality of outer shell tunnels 13 are preliminarily constructed so as to be located at the base end of the outer shell portion 10A in a part of the branching/merging portion 10, and have a spectacle-shaped cross section extending in a ring shape along the circumferential direction Z. Construction is performed by excavating the outer shell shield excavator 14 using the circumferential tunnel 15 as a starting base (outer shell shield starting base 150).

In the outer shell tunnel 13, as shown in FIG. 1, an outer shell segment 13A is sequentially assembled behind an outer shell shield excavator 14 (see FIG. 2) during excavation.
In addition, the outer shell tunnel 13 according to the present embodiment carries in the constituent members (steel panel 70 and the like) of the lining body structure 7 when constructing the lining body structure 7 and between the outer shell tunnels 13, 13. Access for carrying out excavated earth and sand when excavating with a connecting shield machine 1 and for transporting a filled concrete 71 placed between the steel panels 70, 70 arranged on the inner and outer circumferences of the outer shell 10A. It is used as a tunnel.

  The lining frame structure 7 includes a steel panel 70 divided into a plurality in the circumferential direction Z on each of the inner peripheral side and the outer peripheral side of the outer shell portion 10A, the steel panel 70 on the inner peripheral side and the outer peripheral side and the outer peripheral side The filled concrete 71 filled between the steel panels 70 and the shear reinforcement member 73 that connects the inner and outer steel panels 70 are provided.

The steel panels 70, 70 adjacent to each other in the circumferential direction Z and the tunnel direction X are connected by a joint 74 such as a bolt or a reinforcing bar. The steel panel 70 is integrally manufactured in advance in a factory, and is transported to a predetermined assembly position in the outer shell 10A and assembled. The steel panel 70 includes a rectangular skin plate, end plates erected from respective peripheral edge portions of the outer peripheral four sides of the skin plate, and reinforcing ribs arranged vertically and horizontally inside the end plate surrounded by the end plates. Have
The filled concrete 71 is filled in the entire space between the steel panels 70 arranged on the inner and outer circumferences. The filling work of the filled concrete 71 is performed from the outer shell tunnel 13 by using the steel panel 70 on the inner peripheral side and the steel panel 70 on the outer peripheral side as a frame.

Next, the connection shield machine 1 for widening excavation between the outer shell tunnels 13, 13 will be specifically described.
As shown in FIGS. 4 to 7, the coupled shield machine 1 is provided so as to be capable of advancing with four sides covered with skin plates 21, and a lining for assembling the excavation chamber 2A and the outer shell segment (lining member) inside the shield machine. A shield body 2 having a partition wall 22 that partitions the assembly chamber 2B in the front-rear direction Df (tunnel direction X), and an excavation device that is provided in the excavation chamber 2A and is capable of excavating the ground on the cutting face side from the excavation chamber 2A. 31 is provided. In this embodiment, the steel panel 70 of the lining frame structure 7 is used as the outer shell segment.
Here, in the present embodiment, the excavation area M per one time of the coupled shield machine 1 is set to correspond to one ring of the outer shell segment 13A in the outer shell tunnel 13.

The shield body 2 has a skin plate 21 that forms an outer shell, a partition wall 22 that divides the inside of the skin plate 21 in the front-back direction Df, and a steel panel 70 that is assembled in the lining assembly chamber 2B in the shield body 2 and is opposite to the steel panel 70. And a propulsion jack 23 that takes power.
The excavation chamber 2A is provided with an excavation device 31, and the lining assembly chamber 2B is provided with the propulsion jack 23 and the erector 32 (lining assembly device).
Side protectors 4 (4A, 4B) capable of projecting forward from the excavation chamber 2A are provided on the left and right sides of the front portion of the skin plate 21.

The skin plate 21 includes a top plate 24 located on the outer peripheral side of the outer shell portion 10A, a bottom plate 25 located on the inner peripheral side, and a pair of left and right side plates 26 connecting the top plate 24 and the bottom plate 25. And are equipped with. The top plate 24 and the bottom plate 25 are provided with the same length dimension in the front-rear direction Df.
Here, in the coupled shield machine 1, the top plate 24 and the bottom plate 25 are arranged to face each other with their surface directions parallel to each other, and the direction orthogonal to each plate 24, 25 is the vertical direction Dh. In the direction Dh, the top plate 24 side is called the upper side and the upper side, and the bottom plate 25 side is called the lower side and the lower side.

  The pair of side plates 26 (26A, 26B) has a front end 26a at the same position as the front ends of the top plate 24 and the bottom plate 25, and a rear end 26b at the rear ends of the top plate 24 and the bottom plate 25. A side opening 261 is formed in front of 24b and 25b. That is, the lining assembly chamber 2B communicates with the inside of the outer shell tunnel 13 through the side opening 261. Using this side opening 261, a lining member (such as a steel panel 70 described later) that has been brought into a predetermined position using the inside of the outer shell tunnel 13 is covered with the erector 32 in the lining assembly chamber 2B. The steel panel 70 can be assembled inside the top plate 24 and the bottom plate 25 by bringing it inside. Thereby, the widening tunnel 19 in which the steel panels 70 are assembled to the outer peripheral portion and the inner peripheral portion of the outer shell portion 10A in the outer shell widening portion excavated by the connection shield machine 1 (see FIGS. 1, 3, and 4). Is built.

  As shown in FIGS. 4, 6 and 7, the side plate 26 has a tapered surface 262 that is directed inward in the left-right direction Dv at the upper end and the lower end, and a joining surface 263 provided at the upper end of the tapered surface 262. , Are provided. The taper surface 262 and the joining surface 263 extend further rearward than the rear end portion 26b of the side plate 26 and are located at the same positions as the rear end portions 24b and 25b of the top plate 24 and the bottom plate 25, respectively.

The tapered surface 262 is an inclined surface that gradually inwards in the left-right direction Dv as it goes upward (downward in the case of the lower end of the side plate 26), and is liquid-tight with respect to the cut end surface 13a of the outer shell segment 13A. It is provided so as to be able to abut in such a state and slidable in the front-rear direction Df. The joining surface 263 is arranged with its surface facing upward, and is fixed in a state where the side edge portion 24a of the top plate 24 is placed.
By attaching a friction reducing material such as Teflon (registered trademark) to the tapered surface 262, it is possible to reduce friction when the shield body 2 is moved forward, and for example, the propulsion jack 23 necessary for movement. The equipment ability of can be reduced.

  The top plate 24 is divided into two in the left-right direction Dv. The outer edge portion 24c on the outer side in the left-right direction Dv of each of the divided top plate 24A, 24B is fixed while being placed on the joint surface 263 of the side plate 26. Further, the inner edge portions 24d, 24d on the inner side in the left-right direction Dv of both the top plates 24A, 24B that are divided are vertically stacked at the center in the left-right direction Dv between the pair of side plates 26, 26. It is located at.

  On the lower surface of the fixed top plate 24A that overlaps the lower side, a plurality of (four here, two on the side of the excavation chamber 2A and two on the side of the lining assembly chamber 2) horizontal slide jacks 241 are provided on the lower surface of the cylinder. The base end portion is fixed in a state where the is directed in the left-right direction Dv. The jack tip 241a of the horizontal slide jack 241 is fixed to the lower surface of the moving top plate 24B located above the fixed top plate 24A. By expanding and contracting the horizontal slide jack 241, the movable top plate 24B can be slid in the left-right direction Dv with respect to the fixed top plate 24A. At this time, both top plate plates 24A and 24B are provided with an overlapping amount that does not cause a gap due to opening between the inner edge portions 24d and 24d even when the extension amount of the horizontal slide jack 241 is the longest. ing.

  The bottom plate 25 is divided into two in the left-right direction Dv. The outer edge portion 25c on the outer side in the left-right direction Dv of each of the divided bottom plate plates 25A and 25B is fixed to the lower surface of the joint surface 263 of the side plate 26. In addition, the inner edge portions 25d, 25d on the inner side in the left-right direction Dv of the divided bottom plate plates 25A, 25B are vertically overlapped at the center in the left-right direction Dv between the pair of side plates 26, 26. It is arranged.

  On the upper surface of the fixed bottom plate 25A that overlaps with the upper side, a plurality of (here, four on the side of the excavation chamber 2A and two on the side of the lining assembly chamber 2B) horizontal slide jacks 251 are arranged in the lateral direction of the cylinder. The base end is fixed in a state of facing the direction Dv. The jack tip 251a of the horizontal slide jack 251 is fixed to the lower surface of the bottom plate 25B located below the fixed bottom plate 25A. By expanding and contracting the horizontal slide jack 251, the bottom plate 25B can be slid in the left-right direction Dv with respect to the fixed bottom plate 25A. At this time, the two bottom plate plates 25A and 25B are provided with an overlapping amount that does not cause a gap due to opening between the inner edge portions 25d and 25d of both sides even when the extension amount of the horizontal slide jack 251 is the longest. There is.

As described above, the skin plate 21 has a structure in which the U-shaped steel shells 21A and 21B in a cross-sectional view viewed from the front-rear direction Df overlap each other from both sides with the opening side inside in the left-right direction Dv. . Then, by simultaneously expanding and contracting the plurality of horizontal slide jacks 241, 251, the widthwise dimension of the steel shells 21A, 21B of the left and right divided skin plates 21 in the horizontal direction Dv can be increased or decreased.
In addition, the adjustment width by the expansion and contraction of the steel shells 21A and 21B at this time uses the horizontal slide jacks 241 and 251 equipped on the fixed-side steel shell 21A having the U-shaped structure. Expand the shell 21B. When the overlap margin due to the expansion becomes small, a frame material made of steel panel material or the like (not shown) may be added each time to secure a predetermined yield strength.
Further, the water blocking of the connecting portion between the outer shell segment 13A and the skin plate 21 can be coped with by a sealing material, an emergency water blocking injection device or the like.

  The pair of left and right side protectors 4A and 4B are arranged so as to cover the outer surface of the side plate 26, respectively, as shown in FIGS. 5 and 6, and do not project from the front end portion 26a of the side plate 26 toward the cutting face. It is slidably provided so as to project forward from P1 to a predetermined projecting position P2.

  Each side protector 4A, 4B slides in the front-rear direction Df due to the expansion and contraction of the front-rear slide jack 41 fixed to the inner surface of the side plate 26. The front-rear slide jack 41 is arranged such that the expansion/contraction direction is in the front-rear direction Df, the jack base end portion 41b is fixed to the inner surface of the side plate 26, and the jack tip end portion 41a is in contact with the front end portions 4a of the side protectors 4A and 4B. It is fixed to the plate 42. The upper edge portion 4b and the lower edge portion 4c of the side protectors 4A and 4B are guided by the tapered surface 262 of the side plate 26 and slid in the front-rear direction Df. The side protectors 4A and 4B are set so that the protruding tips (contact plates 42 described later) come into contact with the rear end surface 13b forming the slit opening 13c of the outer shell segment 13A.

  As described above, the excavation area M (see FIGS. 9A and 9B) per one time of the coupled shield machine 1 is set so as to correspond to one ring of the outer shell segment 13A in the outer shell tunnel 13. Since the protrusion lengths of the side protectors 4A and 4B will be described later in detail, the outer shell segment 13A facing the excavation area M is removed when excavating, so that it is equivalent to the width dimension of the outer shell segment 13A for one ring. It is set to a different length.

As shown in FIG. 4, the contact plate 42 is provided so as to project from the front end portion 4a of the side protector 4 toward the inner side in the left-right direction Dv, and has a cut-out opening (cut-opening opening 13c (FIG. 5) in the outer shell segment 13A. , (See FIG. 9A)), which has a contact surface 42a facing the rear end surface 13b. The inner peripheral surface of the contact plate 42 is formed with a curved surface having substantially the same curvature as the outer peripheral surface of the outer shell segment 13A.
During excavation by the excavation device 31, the side protector 4 is projected forward to bring the contact plate 42 into contact with the rear end surface 13b of the outer shell segment 13A, thereby closing the slit opening 13c from the outside of the outer shell tunnel 13. As a state, the ground of the excavation region M which is in the communication state and the inside of the outer shell tunnel 13 can be isolated by the side protectors 4A and 4B.

  As shown in FIG. 5, the partition wall 22 is fixed to the skin plate 21 around the entire circumference when viewed in the front-rear direction Df. Similarly to the skin plate 21, the partition wall 22 is also divided into two in the left-right direction Dv, and the partition walls 22A and 22B that are divided into the left and right overlap each other in the front-rear direction Df at the center in the left-right direction. The divided partition walls 22A and 22B are also configured to slide in synchronization with the expanding and contracting operations of the divided steel shells 21A and 21B.

To the rear surface 22b of the partition wall 22 on the side of the lining assembly chamber 2B, the base end portions of the propulsion jacks 23 are fixed on the upper side and the lower side of the lining assembly chamber 2B while being arranged in the left-right direction Dv. The stroke of the propulsion jack 23 corresponds to the excavation stroke and matches the width dimension of one ring of the outer shell segment 13A.
Further, it is preferable that the partition wall 22 be provided with a supporting column (not shown) to maintain the structural proof strength of the entire shield body 2.
In this embodiment, the reaction force of the propulsion jack 23 can be applied to the shear reinforcing member 73 (see FIG. 1) for reinforcing the opening installed in the outer shell tunnel 13.

  On the excavation chamber 2A side of the top plate 24 and the bottom plate 25, a sled portion 33 having a sharp front end is provided. A cutter bit 33a is attached to the tip of the sled portion 33. When the shield body 2 is moved forward by extending the propulsion jack 23, the sled portion 33 easily penetrates into the ground of the excavation area M between the side protectors 4A and 4B that has been projected in advance, so that the shield body 33 easily penetrates. 2 becomes easier to promote.

The excavator 31 has an arm portion 35 and a drum type cutting portion 34 used for a road header. The excavation device 31 has a configuration capable of cutting with a free cross section.
The mounting portion 35a of the arm portion 35 is provided on a movable base (not shown) that is movable in the front-rear direction Df and the left-right direction Dv.
The cutting portion 34 can be changed according to the shape and size of the excavated cross section.
For the earth and sand excavated by the excavator 31, a well-known earth and sand unloading facility (not shown) such as a screw conveyor or a vacuum transfer device can be used.

  As shown in FIGS. 5 and 7, the erector 32 is fixed to the skin plate 21 in the lining assembly chamber 2B, and has a gripping portion 32a at the tip thereof that can be gripped by the steel panel 70. The erector 32 is provided between a predetermined assembly position of the steel panel 70 gripped by the grip portion 32a in the lining assembly chamber 2B and a position where the steel panel 70 carried into the outer shell tunnel 13 can be gripped. It is equipped with an arm mechanism that can be moved.

Here, the water blocking structure of the connection shield machine 1 will be described with reference to FIG.
The coupled shield machine 1 of the present embodiment has a water blocking structure in which the entire shield body 2 is in liquid-tight contact with the outer ground and the existing tunnel 13, and is, for example, a first water blocking member made of a member made of rubber or the like. It has S1-6th water stop member S6.

  The first water blocking member S1 is provided in a state of being attached to the contact surface 42a located on the front surface of the contact plate 42 of each side protector 4A, 4B. The second water blocking member S2 is provided in a state of being attached to the upper end surface and the lower end surface of each side protector 4A, 4B. The third water blocking member S3 is provided in a state of being attached to the upper surface on the tapered surface 262 of each side plate 26. The fourth water blocking member S4 is attached to one of the inner surface of the side plate 26 and the outer surface of the side protectors 4A and 4B on the base end side, and is provided between the both.

The fifth water blocking member S5 is provided on the slide portion of the skin plate 21 in the left-right direction Dv. Specifically, a ceiling water stop member S51 disposed between the pair of left and right ceiling plate plates 24A and 24B, a partition water stop member S52 disposed between the left and right partition walls 22, and a pair of left and right bottom plate plates 25. (The sled portion 33 in FIG. 8) and the bottom plate water blocking member S53 disposed therebetween.
The sixth water stop member S6 is provided in a state of being adhered along the tail end portion of the skin plate 21 (see FIGS. 1, 4, and 5).

Next, a method for connecting between tunnels using the above-described connecting shield machine 1 will be specifically described with reference to the drawings.
First, as shown in FIG. 2 and FIG. 3A, a starting base of a not-shown double circular circumferential shield excavator for excavating the circumferential tunnel 15 on a part of the side wall of the ramp tunnel 12 (circular shield starting Build base 17). For example, the propulsion unit 18 shown in FIG. 2 is excavated from the ramp tunnel 12, the ground improvement portion 100 is formed around the propulsion unit 18, and then the tunnel excavated by the propulsion unit 18 is widened to expand the circumference shield starting base 17 Can be built.

  Then, as shown in FIG. 3A, the compound circular circumference shield excavator is driven in the circumferential direction Z, and a spectacle-shaped circumferential segment (not shown) is assembled in the shield machine body. Next, the constructed circumferential tunnel 15 is used as an outer shell shield starting base 150, and the outer shell shield excavator 14 having a circular cross section shown in FIG.

  The plurality of outer shell tunnels 13 are constructed in the outer shell portion 10A of the branching and merging portion 10 to be constructed in a state of being arranged at intervals in the circumferential direction Z. The outer shell tunnel 13 is excavated by an outer shell shield excavator 14 and is formed by an outer shell segment 13A (see FIG. 1) assembled behind the outer shell shield excavator 14. A part of the outer shell portion 10A is constructed around the main tunnel 11 and the ramp tunnel 12 by the plurality of outer shell tunnels 13.

  Then, after constructing the outer shell tunnel 13 or at the same time as the outer shell tunnel 13 is dug, a frozen pipe is inserted into the ground by a freezing method from the inside of the outer shell tunnel 13 toward the surroundings to improve the ground. The ground improvement area is an area where the lining frame structure 7 is arranged and a predetermined range around the area. That is, the ground between the outer shell tunnels 13, 13 adjacent to each other in the circumferential direction Z is ground improved by a freezing method (or a chemical solution injection method, etc.), and an improvement zone surrounding the construction planned region of the lining frame structure 7 is formed. Form.

  After that, as shown in FIG. 1, both side portions of the outer shell segment 13A in the circumferential direction Z are cut open by excavation of the connecting shield machine 1, and a widening tunnel 19 that connects the adjacent outer shell tunnels 13 and 13 is provided.

  Specifically, first, as shown in FIG. 9A, one ring of outer shell segment facing the excavation region M located in front of the shield body 2 on the side walls of the adjacent outer shell tunnels 13, 13. 13A is disassembled to form a slit opening 13c.

  Subsequently, as shown in FIG. 9B, the left and right side protectors 4A and 4B in the connection shield machine 1 are projected forward. At this time, as shown in FIG. 5, the contact plates 42 of the side protectors 4A, 4B are brought into contact with the rear end surface 13b of the outer shell segment 13A facing the slit opening 13c. This can prevent the excavation region M from being exposed to the outer shell tunnel 13, and prevent the ground of the excavation region M from entering the outer shell tunnel 13 through the slit opening 13c during excavation by the coupling shield machine 1. Can be installed safely.

Next, as shown in FIG. 10( a ), the excavation device 31 excavates the ground in the excavation region M in front of the shield body 2, takes in the excavated earth and sand into the excavation chamber 2 A, and lining it through the partition wall 22. It is discharged to the assembly chamber 2B side. Then, along with the excavation, the propulsion jack 23 is extended and the shield main body 2 is advanced so as to be located in the excavated region M (see FIG. 10B). The front and rear slide jacks 41 of the side protectors 4A and 4B are also contracted in accordance with the forward movement of the shield body 2.
As shown in FIG. 6, as the shield body 2 advances, the steel shells 21A and 21B of the skin plate 21 that is divided into left and right slide so that the outer wall of the outer shell tunnel 13 and the side plate 26 are not separated from each other. Then, the shield body 2 is expanded so that the width dimension of the shield body 2 is increased.

  Then, when the excavation for one ring is completed, in the lining assembly chamber 2B, the propulsion jack 23 is pulled back and the vacant space is located on the inner peripheral side and the outer peripheral side of the outer shell portion 10A by using the erector 32. Assemble the steel panel 70.

Next, as shown in FIG. 1, when the construction of the widening tunnel 19 between the outer shell tunnels 13 is completed, the filling concrete 71 is filled between the steel panels 70 located on the inner peripheral side and the outer peripheral side. The lining frame structure 7 is constructed. In other words, the outer shell tunnel 13 and the widening tunnel 19 are used to connect the steel panels 70 in the circumferential direction Z, and the outer shell portion 10A is assembled over the entire circumference of each of the inner circumference side and the outer circumference side.
Next, as shown in FIGS. 3A and 3B, the inside of the outer shell 10A is excavated, and the segments of the main tunnel 11 and the ramp tunnel 12 at the portion covered by the outer shell 10A are disassembled and removed. Thus, the branch/merge unit 10 forming a large space can be constructed.

Next, the operation of the joint structure of the panel structure described above will be described in detail with reference to the drawings.
In the present embodiment, it is possible to move forward while excavating between the outer shell tunnels 13 and 13 with the excavation device 31 in the shield body 2 covered with the skin plates 21 on all sides. Then, the width dimension of the shield body 2 in the left-right direction Dv can be changed by sliding the left and right divided skin plates 21 in the direction of approaching and separating from each other. Therefore, even when the distance between the outer shell tunnels 13, 13 changes, the width dimension of the shield body 2 can be adjusted according to the distance, and the skin plate 21 and the outer shell tunnel 13 can be adjusted. It is possible to dig while protecting the natural ground with the gap between them constantly closed.
As described above, in the present embodiment, since it is possible to perform the excavation while exposing the natural ground between the outer shell tunnels 13 and 13 to the minimum, it is possible to prevent the natural rock from collapsing, and a safe and reliable construction method is provided. There are advantages.

  In addition, in the present embodiment, by projecting the side protectors 4A and 4B forward before excavation, the outer shell tunnel 13 and the ground of the excavation region M can be blocked by the side protectors 4A and 4B, and the outer shell tunnel It is possible to minimize that 13 is opened to the ground of the excavation area M. Therefore, the state in which the ground being excavated is exposed in the outer shell tunnel 13 is minimized, so that the widening tunnel 19 can be constructed by a safe and reliable excavation work.

  In addition, in the present embodiment, the construction efficiency can be improved by starting from the position where the separation between the outer shell tunnels 13 and 13 is minimum and digging toward the position where the separation is maximum. it can. In this case, since the connection shield machine 1 can be assembled at a place where the distance between the outer shell tunnels 13 and 13 is the smallest, the assembling work can be safely performed at a place around the assembly area where the ground condition is good. it can.

  In addition, in the present embodiment, since the entire shield body 2 has a water stop structure that is in liquid-tight contact with the external ground and the existing tunnel 13, it is relatively slidable in the left-right direction Dv during excavation. Not only the skin plate 21 but also the entire shield body 2 can be kept liquid-tight in contact with the external ground and the existing tunnel 13 to stop the water.

  As described above, in the tunnel coupling shield machine and the tunnel coupling method according to the present embodiment, it is possible to excavate the ground safely and efficiently, and to cope with changes in the distance between the tunnels. ..

  Although the embodiments of the tunnel connecting shield machine and the tunnel connecting method according to the present invention have been described above, the present invention is not limited to the above embodiments, and can be appropriately changed without departing from the gist thereof. is there.

  For example, in the present embodiment, the side shields 4A and 4B are provided as the connection shield machine 1, and the side protectors 4A and 4B are arranged on both sides of the excavation area M before excavation to stabilize the ground in the excavation area M. However, it is not limited to providing the side protectors 4A and 4B, and the side protectors 4A and 4B can be omitted.

  Further, in the excavation device 31 of the coupled shield machine 1, in the present embodiment, the drum-type cutting portion 34 of the load header is adopted, but the present invention is not limited to this, and for example, another cutting mechanism such as a backhoe. May be adopted.

  Furthermore, the present embodiment is an application example in the case of constructing a large-section road tunnel, but in the case of constructing a tunnel of various scales, uses, and forms having a large-section underground cavity as described above. It can be widely applied in general, and various design changes are possible depending on the size and shape of the underground cavity in the tunnel to be constructed, and various conditions such as the surrounding environment. Further, the size of the outer shell portion 10A that constitutes the branching/merging portion 10, the structure of the body, and the construction method are not limited to those in the above-described embodiment, and are set according to specifications such as road tunnels and ground conditions to be set. It can be set appropriately.

  Further, the panel structure is not limited to the panel structure constructed in the outer shell portion 10A of the branching/merging portion 10 in the road tunnel as in the present embodiment, and is a panel structure adopted for other purposes. It doesn't matter. Furthermore, the panel structure is not shaped to extend in the circumferential direction. For example, it can be applied to floor slabs such as roads.

  In addition, it is possible to appropriately replace the constituent elements in the above-described embodiments with known constituent elements without departing from the spirit of the present invention.

1 Connection shield machine (tunnel connection shield machine)
2 Shield body 2A Excavation room 2B Lining assembly room 4, 4A, 4B Side protector 7 Lining structure 10 Branch junction 10A Outer shell 11 Main tunnel 12 Lamp tunnel 13 Outer shell tunnel (existing tunnel)
13A Outer shell segment 19 Widening tunnel 21 Skin plate 21A, 21B Steel shell 22 Partition wall 23 Propulsion jack 24 Top plate 25 Bottom plate 26 Side plate 31 Excavator 32 Electa 70 Steel panel (lining member)
Df longitudinal direction Dh vertical direction Dv lateral direction

Claims (5)

A tunnel connecting shield machine for digging between existing tunnels provided at intervals and for constructing a widening tunnel for connecting the existing tunnels,
A shield main body that is provided so as to be capable of advancing by covering four sides with skin plates and that has a partition wall that partitions the excavation chamber and the lining assembly chamber that assembles the lining member in the front-rear direction inside the shield machine,
An excavation device that is provided in the excavation chamber and is provided so as to excavate the ground on the cutting face side from the excavation chamber,
Equipped with
The skin plate includes a top plate, a bottom plate, and left and right side plates,
The pair of left and right side plates are slidably brought into contact with the outer wall of one of the existing tunnels so that their upper and lower ends are slidable in the front-back direction,
The tunnel plate connecting shield machine is characterized in that the skin plate is divided in the left-right direction, and the divided skin plate is slidably provided in the left-right direction.   The inter-tunnel connection shield machine according to claim 1, wherein the shield body is provided with a side protector capable of projecting forward from the side plate.   The tunnel-to-tunnel shield machine according to claim 1 or 2, wherein the shield main body has a water blocking structure that is in liquid-tight contact with the outer ground and the existing tunnel. A tunnel connection method for constructing a widening tunnel connecting the existing tunnels by using the tunnel connection shield machine according to any one of claims 1 to 3.
A step of providing an opening in an excavation region located in front of the shield body on the side wall of the existing tunnel;
While excavating the ground in the excavation area in front of the shield body by the excavation device, taking in excavated earth and sand into the excavation chamber, and discharging to the lining assembly chamber side through the partition wall,
Advancing the shield body to be located in the excavated excavation area,
Along with the advance of the shield body, a step of sliding the left and right skin plates so that the outer wall of the existing tunnel and the side plate are not separated from each other,
A step of assembling the lining member in the lining assembly chamber,
A method for connecting between tunnels, which comprises:   The excavation direction by the tunnel connecting shield machine is started from a position where the separation between the existing tunnels is minimum, and the excavation is performed toward a position where the separation is maximum. The method for connecting tunnels described.

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