JP2007262855A - Pressure bearing member for use in constructing tunnel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pressure bearing member which is advantageous to improve branch tunnel construction efficiency when a branch tunnel is constructed from a narrow master tunnel. <P>SOLUTION: A reaction bearing member 52 has a profile insertable into a rear trunk 50 of a shield machine, and is formed of: front and rear substrates 54, 56 which exhibit an annular shape and face to each other; and a plurality of column members 58 arranged between the front and rear substrates 54, 56 at circumferential intervals in a manner extending longitudinally, for connecting between the front and rear substrates 54, 56. The reaction bearing member 52 is incorporated in the rear trunk 50, and exposed in the master tunnel 12 according to the advancement of the shield machine 19, to take up a space inside the master tunnel 12. When a plurality ones of the column members 58 and the rear substrate 56 are detached, an opening 60 is formed therein in a manner opening in a lateral direction and in an axial direction of the reaction bearing member 52, and materials and equipment are taken in the interior of the shield machine 19 while excavated soil is discharged via the opening 60. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a reaction force receiving member for tunnel construction that is advantageous in performing efficient construction when a new tunnel is constructed in a form branched from a parent tunnel.

A method of assembling an excavating machine for branching a new tunnel in an already installed tunnel, pushing it into the ground in a partially completed state, and repeating the assembly and extrusion sequentially to complete the start of the excavating machine (Patent Document 1, Patent Document 2).
However, when the diameter of the parent tunnel is relatively small, branching a new tunnel from the already installed parent tunnel is a very inefficient operation in a confined space.
JP 2003-278482 A JP 2003-336480 A

For example, in normal shield start, a ring-shaped reaction force receiving member for temporary segment connection can be installed behind the assembled shield machine and propelled, but when the diameter of the parent tunnel is relatively small, such as a sewer tunnel, It is unavoidable to carry shield machines in divided sizes in a limited space.
And even if the shield machine is carried in divided, there is not enough room in the rear space of the divided shield machine, and if a ring-shaped reaction force receiving member for segment connection is installed, equipment (segment etc.) can be carried in or excavated soil Unloading (especially mud pressure) becomes very difficult.

  The present invention has been devised in view of the above circumstances, and the object of the present invention is to provide a tunneling reaction force that is advantageous in increasing the construction efficiency of a branch tunnel when constructing a branch tunnel from a narrow parent tunnel. It is to provide a receiving member.

  In order to achieve the above object, the present invention provides a front cylinder provided with a cutter and its drive unit, and a jack for propulsion at a plurality of locations spaced in the circumferential direction of the inner peripheral surface following the front cylinder. The inner cylinder is provided with an erector for assembling the segment ring, and a water stop member is provided on the inner peripheral surface to contact the outer peripheral surface of the assembled segment ring to prevent intrusion of groundwater. A steel reaction force receiving member used when constructing a new branch tunnel from an already installed parent tunnel using a mud pressure shield machine composed of a rear trunk, wherein the reaction force receiving member is The front and rear substrate portions are formed in a contour inserted into the rear cylinder and are opposed to each other in an annular shape, and the front and rear portions are spaced apart in the circumferential direction of the front and rear substrate portions. To A plurality of column members connecting the front substrate portion and the rear substrate portion, and at least two of the plurality of column members are detachably provided to the front substrate portion, and The portion of the rear substrate portion to which the at least two column members are connected is detachable from the remaining portion of the rear substrate portion.

In the present invention, the shield machine is advanced while receiving the reaction force using the reaction force receiving member.
As the shield machine moves forward, the reaction force receiving member is exposed in the parent tunnel and occupies the space in the parent tunnel. However, a plurality of pillar members are connected to the substrate portion after the pillar members are connected. An opening is formed by removing the location.
Therefore, although there is no room for securing the equipment such as segments behind the shield machine, the equipment can be carried into the shield machine through this opening.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
First, the outline of the construction procedure of the branch tunnel is as follows.
Fix the entrance ring on the wall of the parent tunnel. Next, only the front body of the shield machine is placed inside the entrance ring. Next, excavation is started by advancing the front trunk while receiving reaction force on the wall surface of the parent tunnel, and when the front trunk is advanced to create a space in the parent tunnel, the middle trunk is connected to the front trunk. Next, excavation is performed by advancing the front trunk and the middle trunk while receiving reaction force on the wall surface of the parent tunnel, and when a space is created in the parent tunnel, the rear trunk is connected to the middle trunk. The reaction force receiving member of the present invention is incorporated in the rear cylinder.
Hereinafter, it demonstrates in order of the above-mentioned construction procedure.

FIG. 1 is a sectional front view of the parent tunnel and the entrance ring, FIG. 2 is an explanatory view of the rear part of the entrance ring, and FIG. 3 is a sectional plan view of the parent tunnel and the entrance ring.
In the drawing, reference numeral 12 indicates a parent tunnel that has already been constructed, reference numeral 14 indicates the tunnel wall thereof, and the tunnel wall 14 has a cylindrical shape. In this embodiment, the tunnel is for sewerage.
Reference numeral 16 denotes an entrance ring used when a new branch tunnel 18 is constructed from the parent tunnel 12, and reference numeral 20 denotes a mud pressure shield machine 19 used when constructing the branch tunnel 18 (see FIG. 6). Shows the front torso.
As shown in FIG. 6, the shield machine 19 includes a front cylinder 20, a middle cylinder 40 following the front cylinder 20, and a rear cylinder 50 following the middle cylinder 40.
The front cylinder 20 is provided with a cutter 20A, a driving unit 20B thereof, a screw conveyor 20C for discharging earth and sand (see FIG. 4), and the like.
A propulsion jack 42 (see FIG. 5) or the like is disposed on the middle barrel 40, and the middle barrel 40 is also a portion that is foldably connected to the front barrel 20 and functions when the course is curved.
The rear trunk 50 is provided with an erector for assembling segment rings and the like, in which the segment rings are sequentially assembled.

The shield machine may be composed of a front trunk and a rear trunk. In this case, the rear trunk is composed of the middle trunk 40 and the rear trunk 50 of the present embodiment. Become.
In the present embodiment, the middle cylinder 40 and the rear cylinder 50 are configured by two cylinders joined together in the front-rear direction, and as shown in FIGS. 5 and 6, a cylinder 44 at the rear of the middle cylinder 40, The cylinder 44 in front of the rear cylinder 50 is common, the front half of the common cylinder 44 constitutes the rear part of the middle cylinder 40, and the rear half of the common cylinder 44 constitutes the front part of the rear cylinder 50. is doing.
When constructing the branch tunnel 18, the entire shield machine 19 cannot be carried into the parent tunnel 12 due to space problems, and only the front trunk 20 is carried first.

The entrance ring 16 has a cylindrical front portion 30 and a cylindrical rear portion 32 following the front portion 30.
Both the front part 30 and the rear part 32 are made of steel and are formed with a uniform inner diameter larger than that of the mud pressure shield machine 19 used when the branch tunnel 18 is constructed, and the outer peripheral surface thereof is a single cylinder. It is provided so as to extend on the surface.
The front portion 30 includes an annular plate-shaped base portion 30A, left and right side surface portions 30B protruding forward from the left and right sides of the base portion 30A, and a front open cut provided between the left and right side surface portions 30B. 30C.
The left and right side surface portions 30B and the notches 30C are formed in such a shape that the entire edges of the left and right side surface portions 30B are in contact with the cylindrical inner peripheral surface of the tunnel wall 14 of the parent tunnel 12.
The edges of the left and right side portions 30B are fixed to the inner surface of the tunnel wall 14 to be opened, for example, by welding.
Openings 3002 are provided in the left and right side portions 30B, and a transparent plate 3004 made of a synthetic resin such as acrylic is attached to the openings 3002, and the transparent plate 3004 allows the inner portion to be visually recognized from the outside of the front portion 30. A window 30D is configured.

The rear portion 32 is provided in an annular plate shape that is continuous with the base portion 30A of the front portion 30, and at least a portion 32A in the circumferential direction thereof is provided detachably with respect to the remaining portion 32B.
When the portion 32A is removed from the remaining portion 32B, the remaining portion 32B is formed with an open opening 32C laterally.
The height of the opening 32 </ b> C has a height H that is larger than the diameter of the shield machine 19 that constructs the branch tunnel 18.
Further, a water stop member 34 is attached to the entire inner surface of the rear portion 32 to stop the groundwater that is elastically contacted with the body of the shield machine 19 and enters the main tunnel 12 through the body of the shield machine 19. ing.

In this embodiment, first, the entrance ring 16 is carried into a location in the parent tunnel 12 where the branch tunnel 18 is to be constructed, and the edges of the left and right side surface portions 30B of the entrance ring 16 are placed on the inner surface of the tunnel wall 14, for example, Fix by welding.
Next, a portion 32A in the circumferential direction of the rear portion 32 is removed, and the opening 32C is exposed to the remaining portion 32B.
Next, only the front trunk 20 of the mud pressure shield machine 19 used when constructing the branch tunnel 18 is carried into the parent tunnel 12 and arranged inside the remaining portion 32B of the rear portion 32 from the opening 32C.
And if the front trunk | drum 20 is arrange | positioned inside the remaining part 32B of the rear part 32, the part 32A of the removed circumferential direction will be attached with respect to the remaining part 32B, and the rear part 32 will be assembled.

Next, a plurality of jacks are arranged via a gantry between the back surface of the front trunk 20 of the shield machine 19 and the tunnel wall 14 on the side opposite to the place where the entrance ring 16 is installed. It is given to the front cylinder 20, and the front cylinder 20 is advanced while excavating by the rotation of the cutter 20A. In this case, various well-known members can be used for the mount.
This excavation situation is visible from the transparent window 30D and varies depending on the excavation situation, such as adjusting the earth pressure in the screw conveyor, the amount of soil discharge, and exerting a large force with which jack of a plurality of jacks. Measures are taken.

Then, when the front cylinder 20 is moved forward and a space is formed on the back surface of the front cylinder 20 in the parent tunnel 12, the middle cylinder 40 is attached to the front cylinder 20 in the entrance ring 16 as shown in FIGS. 4 and 5. Assemble, this time the front cylinder 20 and the middle cylinder 40 are advanced.
More specifically, as described above, the middle cylinder 40 has two cylinders 40A and 44 coupled to the front and rear. First, as shown in FIG. If only the front cylinder 40A is assembled to the front cylinder 20 to advance, and further space is generated, the rear cylinder 44 is assembled to the cylinder 40A and advanced as shown in FIG.
In this case, as shown in FIG. 4, the propulsive force is applied to the gantry 46 installed at the 14 positions of the tunnel wall facing the back of the front barrel 20 or the middle barrel 40 and the back of the front barrel 20 or the middle barrel 40. A plurality of jacks 48 arranged and a reaction force receiving member 49 spanned between the gantry 46 and the jack 48 are provided.

On the other hand, as shown in FIGS. 4 and 5, the excavated soil in the cutter head chamber C is discharged while holding the face soil pressure by the screw conveyor 20C. However, since the shield machine 20 is divided and loaded, the screw conveyor 20C Also, it must be divided into parts and assembled.
For this reason, it becomes difficult to stabilize the face in excavation until the screw conveyor 20C is assembled into the regular structure shown in FIG. 6, and an auxiliary method such as ground improvement is required.
Therefore, in this embodiment, a shutter gate 2002 is provided on the cutter head partition wall (the boundary surface between the cutter head chamber C and the screw conveyor 20C), and the earth pressure in the cutter head chamber C is adjusted by the gate opening. Therefore, the face is stabilized without the need for an auxiliary method.
In addition, as shown in FIG. 4, when the pipe body of the screw conveyor 20C is short, a ball valve 2004 is provided at the end of the pipe body so as to adjust the earth pressure and the amount of discharged soil in the screw conveyor 20C. Yes.
The pipe body of the screw conveyor 20C and the screw inside the screw conveyor 20C are also added. In this case, if the pipe body is simply disassembled, earth and sand overflows into the parent tunnel 12, and in this case, the shutter gate 2002 is used. Is closed, and pipes and screws are added while preventing sediment from flowing out.
Further, the soil discharged from the screw conveyor 20C and the like is sucked by a vacuum device or conveyed by a velcon.

Further, in the case of extrusion in a state where the length of the shield machine 20 is short before assembling to a regular structure, such as advancement of only the front cylinder 20 or advancement of the front cylinder 20 and the middle cylinder 40, the installation of the shield machine 20 is performed. The pressure is small, the center of gravity of the shield machine 20 is in front of the start stand, and the shield machine 20 is easy to tilt forward.
Therefore, as shown in FIG. 7, the posture control of the shield machine 20 is performed by using the lower jack portion 48 </ b> A among the plurality of propulsion jacks 48 for propulsion and making the upper jack portion 48 </ b> B adjustable for relief pressure. This is done to prevent forward tilt due to a problem with the balance of the center of gravity during excavation.

As shown in FIG. 5, if the rear cylinder 44 is assembled to the cylinder 40 </ b> A and moved forward to create a space behind the cylinder 44, for example, the cylinder 44 is fixed to the entrance ring 16. The rear trunk 50 is carried into the parent tunnel 12, and the rear trunk 50 is coupled to the cylindrical body 44.
Then, when the rear barrel 50 is carried in, the reaction force receiving member 52 of the present embodiment is incorporated in the rear barrel 50.
8A is a side view of the reaction force receiving member, FIG. 8B is a view taken in the direction of arrow B in FIG. 8A, and FIG. 8C is a view taken in the direction of arrow C in FIG.
The reaction force receiving member 52 is formed with a contour inserted into the rear body 50 and has a front substrate portion 54 and a rear substrate portion 56 which are opposed to each other in an annular shape, and the periphery of the front substrate portion 54 and the rear substrate portion 56. A plurality of pillar members 58 extending forward and backward at locations spaced in the direction and connecting the front substrate portion 54 and the rear substrate portion 56 are provided.

The front substrate portion 54 and the rear substrate portion 56 are formed in a shape that fits in a polygon inscribed in the segment outer diameter of the branch shield or a circle equivalent to the same diameter. In the present embodiment, the front substrate portion 54 and the rear substrate portion 56 are provided so as to form a regular octagonal frame.
That is, as shown in FIG. 8B, the front substrate portion 54 is configured such that divided bodies 5402 having eight sides of a regular octagon are detachably connected to each other by a connecting plate 5404 via bolts and nuts.
Further, as shown in FIG. 8C, the rear board portion 56 is configured such that divided bodies 5602 having eight sides of a regular octagon are detachably connected to each other by a connecting plate 5604 via bolts and nuts.
Eight column members 58 are provided, and the column members 58 are provided so as to be positioned at eight corner portions of a regular octagon, and can be attached to and detached from the front substrate portion 54 and the rear substrate portion 56 through bolts and nuts. It is connected to.
In the present embodiment, the reaction force receiving member 52 is incorporated into the rear barrel 50 so that the column member 58 is positioned coaxially with the propulsion jack 42 (see FIG. 5) of the middle barrel 40.
Moreover, in this Embodiment, the column member 58 is comprised with H-shaped steel, and the above-mentioned connection plate 5604 is being fixed to the end of the extending direction of H-shaped steel.
Therefore, in the present embodiment, all of the eight column members 58 are provided so as to be detachable from the front substrate portion 54, and the column members 58 to be removed are portions of the rear substrate portion 56, that is, eight components. Each of the divided bodies 5602 is also provided so as to be detachable from the remaining rear substrate portion 56.

  Then, at least two or more column members 58 are removed from the front substrate portion 54, and the portion of the rear substrate portion 56 to which the at least two column members 58 are connected is replaced by the remaining rear substrate portion 56. As shown in FIG. 6, an opening 60 for carrying materials and equipment into the inside of the shield machine 19 is formed at a place where these members are removed by removing the parts.

If the rear cylinder 50 is carried into the parent tunnel 12 as shown in FIG. 5 and the rear cylinder 50 incorporating the reaction force receiving member 52 is coupled to the cylindrical body 44 as shown in FIG. The plurality of propulsion jacks 42 are extended to abut against the front substrate portion 54 of the reaction force receiving member 52, and a gantry 64 is disposed between the rear substrate portion 56 of the reaction force receiving member 52 and the tunnel wall surface 14. To do.
Then, if the reaction force from the shield machine 19 is received by the tunnel wall surface 14 via the propulsion jack 42, the reaction force receiving member 52, and the gantry 64, the fixation of the cylindrical body 44 and the entrance ring 16 is released. Then, the shield machine 19 is moved forward by expansion and contraction of the propulsion jack 42 and superposition of the gantry 64.
And this time, if the shield machine 19 is advanced while assembling the segment ring by the erector inside the rear trunk 50 and the assembled segment ring is fixed to the opening inside the entrance ring 16, the entrance ring 16 is also removed, While assembling the segment ring, the shield machine 19 is advanced to construct the branch tunnel 18 that branches off from the parent tunnel 12.
The reaction force receiving member 52 is removed together with the entrance ring 16 after fixing the segment ring to the opening inside the entrance ring 16.

According to the present embodiment, the following effects are achieved.
When constructing the branch tunnel 18 from the parent tunnel 12, as shown in FIGS. 5 and 6, since it becomes a narrow start position, it is necessary to carry materials such as segments behind the shield machine 19 at the initial excavation. There is no room for securing space and space for excavating soil.
That is, in normal shield start, a ring-shaped reaction force receiving member for provisional segment connection is installed behind the shield machine 19 and propelled, but in the case of the branch tunnel 18, there is no room in the rear space and the segment connection ring-shaped reaction force is received. When a force receiving member is installed, it is very difficult to carry in materials and equipment and carry out excavated soil (especially mud pressure).
In the present embodiment, the rear barrel 50 in which the reaction force receiving member 52 is preliminarily incorporated is coupled to the cylindrical body 44, and the shield machine 19 is advanced while receiving the reaction force using the reaction force receiving member 52.
The reaction force receiving member 52 does not move forward with the shield machine 19 but remains in the original position in the parent tunnel 12 and is exposed in the parent tunnel 12 to occupy the space in the parent tunnel 12. By removing the member 58 and the divided body 5602 of the plurality of rear substrate portions 56, the opening 60 is formed in the lateral direction and the axial direction of the reaction force receiving member 52.
Accordingly, although there is no room for securing the space for carrying materials and equipment such as segments and the space for carrying out excavated soil behind the shield machine 19, the materials and equipment can be carried into the shield machine 19 from the opening 60. And excavated soil can be discharged.

As shown in FIGS. 5 and 6, when the shield machine 19 moves forward, the inner surface of the rear trunk 50 comes into contact with the outer periphery of the segment ring assembled inside the rear trunk 50 and enters the inner side of the parent tunnel 12. A water stop member 66 made of a steel brush or the like that prevents intrusion of groundwater into the water is provided. And since the assembled segment ring moves back, this water stop member 66 is provided inclining so that the front-end | tip is located back rather than a base end, and is generally formed hard.
Therefore, temporarily, a plurality of jacks are arranged in the parent tunnel 12 facing the shield machine 19 so as to be opposed to the plurality of propulsion jacks 42 in the inner body 40, and the jacks are extended to contact the propulsion jack 42. Although it is conceivable to receive the reaction force of the shield machine 19, the extension direction of the jack is opposite to the direction of the inclination of the water stop member 66, and there is a possibility that the water stop member 66 may be damaged.
On the other hand, the reaction force receiving member 52 of the present embodiment moves in the same direction as the direction in which the segment ring assembled with respect to the water blocking member 66 moves. Absent.

It is a cross-sectional front view of a parent tunnel and an entrance ring. It is explanatory drawing of the rear part of an entrance ring. It is a cross-sectional top view of a parent tunnel and an entrance ring. It is explanatory drawing at the time of the initial excavation of a branch tunnel. It is explanatory drawing at the time of carrying in of the back cylinder in which the reaction force receiving member was incorporated. It is explanatory drawing at the time of carrying in of the back cylinder in which the reaction force receiving member was incorporated. It is explanatory drawing of attitude | position control of a shield machine. (A) is a side view of a reaction force receiving member, (B) is a view from arrow B of (A), and (C) is a view from arrow C of (A).

Explanation of symbols

12 ... Parent tunnel, 14 ... Tunnel wall, 16 ... Entrance ring, 18 ... Branch tunnel, 19 ... Shield machine, 50 ... Rest, 52 ... Reaction force receiving member, 54 ... Front substrate 56 …… Rear substrate portion, 58 …… Column member, 60 …… Open.

Claims (4)

A front cylinder provided with a cutter and its drive part, a middle cylinder provided with jacks for propulsion at a plurality of locations spaced in the circumferential direction of the inner peripheral surface following the front cylinder, A mud pressure type shield composed of a rear trunk provided with a water stop member provided on the inner peripheral surface, which is provided with an erector for assembling the segment ring and abuts on the outer peripheral surface of the assembled segment ring to prevent entry of groundwater It is a steel reaction force receiving member used when constructing a new branch tunnel from a parent tunnel that has already been installed using a machine,
The reaction force receiving member is formed with a contour inserted into the rear body, and has a front substrate portion and a rear substrate portion facing each other in an annular shape, and a circumferential interval between the front substrate portion and the rear substrate portion. A plurality of pillar members extending back and forth at a place where the front substrate portion and the front substrate portion and the rear substrate portion are connected,
At least two or more column members of the plurality of column members are detachably provided to the front substrate portion, and the portion of the rear substrate portion to which the at least two column members are connected is , Provided to be removable with respect to the remaining rear substrate portion,
A reaction force receiving member for tunnel construction.   The at least two or more column members are removed from the front substrate portion, and the portion of the rear substrate portion to which the at least two column members are connected is the remaining portion of the rear substrate portion. 2. The tunnel construction reaction force receiving member according to claim 1, wherein in the removed state, openings for carrying materials and equipment into the shield machine are formed at the removed positions.   The column member is made of H-shaped steel, and is a reaction force receiving member for tunnel construction. The plurality of column members are provided so as to be positioned coaxially with the propulsion jack in a state where the reaction force receiving member is inserted into the rear trunk. The reaction force receiving member for tunnel construction as described.

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