JP2006097329A - Starting method for branch shield - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a starting method for a branch shield using an articulation mechanism, which enables an earth pressure load to be borne by a simple operation. <P>SOLUTION: In an existing tunnel 1, a cutter 3 of the branch shield 2 and a front barrel section 4 are assembled, and a starting port entrance 6 is mounted. The cutter 3 is started to the outside of the existing tunnel 1 from a starting pit mouth 5 by the propulsion of a pipe-jacking jack 18 of the front barrel section 4, and a back end of the front barrel section 4 is started until it is positioned near the back end of the entrance 6. After that, a load bearing member 25 for axially supporting the front barrel section 4 by locking it from the rear is mounted at the back end of the entrance 6. Subsequently, the pipe-jacking jack 18 is retracted, and the branch shield 2 is started after a rear barrel section 33 is assembled in the rear of the front barrel section 4. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention provides a branch shield for assembling and starting a branch shield having a cutter, a front trunk, a rear trunk, and a propulsion jack spanned between the front trunk and the rear trunk in an existing tunnel. It relates to the starting method.

  When a branch shield is started from an existing tunnel, the branch shield is assembled after the branch shield is assembled in the existing tunnel. Here, when starting a branch shield with a total length longer than the width of the existing tunnel and having no space to be assembled in advance in the existing tunnel, after assembling the branch shield cutter and the front trunk, While taking the reaction force on the inner wall of the existing tunnel, the cutter of the branch shield and a part of the front trunk are started outside the existing tunnel, and the rear trunk of the branch shield is assembled in the existing tunnel space behind it. Yes.

  When assembling the rear trunk, a reaction force cannot be applied to the inner wall of the existing tunnel, so the earth pressure load applied to the front surface of the cutter must be supported in some form.

  Conventionally, in order to receive an earth pressure load, as shown in FIG. 9, the outer peripheral portion of the shield frame 53 of the front trunk portion 52 of the branch shield 51 and the floor surface 55 of the existing tunnel 54 are fixed by a connecting member 56. It was. The connecting member 56 is made of steel and is fixed to the shield frame 53 of the branch shield 51 by welding.

Japanese Patent Laid-Open No. 5-179886

  However, since the above-mentioned connecting member 56 must support the earth pressure load applied to the front surface of the cutter 57, the amount of welding is very large, and the work requires a lot of labor and time. Further, when the vehicle restarted, it was necessary to cut the gas at the welded portion, and this work required a lot of labor and time.

  Therefore, the present invention has been developed to solve the above-described problems, and an object of the present invention is to provide a branch shield starting method capable of supporting earth pressure load with a simple operation.

  In order to achieve the above object, the invention of claim 1 includes a branch shield having a cutter, a front trunk, a rear trunk, and a propulsion jack spanned between the front trunk and the rear trunk. In the branch shield start method for assembling and starting in an existing tunnel, the cutter and the front trunk of the branch shield are assembled in the existing tunnel, and a start entrance is attached to the start tunnel position of the existing tunnel, After the cutter and the front trunk portion have entered the start entrance, the cutter is started out of the existing tunnel by the propulsive force of the propulsion jack, and the rear end portion of the front trunk portion is located at the start entrance. A load receiving member that supports in the axial direction by locking the front body portion from the rear to the rear end portion of the start opening entrance after starting until it is positioned near the rear end portion. Ri attached to, then, by degenerating said propulsion jacks, after assembling the rear body part at the rear of the front section, it is the start of a branch shield, characterized in that to start the branch shield.

  According to a second aspect of the present invention, the load receiving member has a locking portion that engages with a rear end portion of the front body portion, and serves as a fixing means along the circumferential direction of the rear end of the start port entrance. The branch shield start method according to claim 1, wherein a plurality of the shields are detachably fixed.

  According to a third aspect of the present invention, when the rear end portion of the front body portion is supported by the start port entrance via the load receiving member, the load receiving member is interposed between the load receiving member and the start port entrance. 3. The branch shield starting method according to claim 1 or 2, wherein a spacing adjusting member is provided between and / or one of the member and the front body portion, and the starting direction of the branch shield is adjusted in advance.

  Furthermore, the invention according to claim 4 is provided with a reaction force receiving stand for receiving a reaction force of the propulsion jack in the existing tunnel behind the front trunk portion for the propulsion by the propulsion jack, A reaction force receiving block is provided between the propulsion jack, the propulsion jack is brought into contact with the reaction force receiving block and propelled for a predetermined distance, and then the propulsion jack is sequentially retracted and the reaction force is rearward of the propulsion jack. The branch shield start method according to any one of claims 1 to 3, which is performed by adding receiving blocks.

  According to a fifth aspect of the present invention, the branch shield is a middle-folded branch shield in which a front body portion and a rear body portion are connected to bendable, and the propulsion jack is a middle-fold jack. A branch shield start method according to any one of the above.

  According to the present invention, an excellent effect is exhibited that the earth pressure load can be supported by a simple operation without performing a welding operation.

  The best mode for carrying out the present invention will be described below in detail with reference to the accompanying drawings.

  FIG. 1 is a side sectional view showing a first step of a branch shield start method according to the present invention, FIG. 2 is a side cross sectional view showing a second step of a branch shield start method according to the present invention, and FIG. FIG. 4 is a side sectional view showing a fourth step of the branch shield start method according to the present invention, and FIG. 5 is a front view of the branch shield. FIG. 6 is an enlarged cross-sectional view showing a starting port entrance and a load receiving member, and FIG. 7 is an enlarged rear view showing the load receiving member.

  The existing tunnel in the present invention also includes a shaft formed from the ground to the underground at the start and end points of the shield machine.

  Such a branch shield has a total length longer than the inner diameter of the existing tunnel having a circular cross section, and there is no space for assembling the branch shield in the starting direction in the existing tunnel. In the present embodiment, an example will be described in which the branch shield is a half-branched branch shield in which the front body portion and the rear body portion are connected to bendable to each other.

  Such a middle-folded branch shield has a cutter, a front body part, a rear body part, and a propulsion jack (in this embodiment, a middle-folding jack) spanned between the front body part and the rear body part. ing.

  In order to assemble and start the middle-folded branch shield, first, as shown in FIG. 1, the cutter 3 and the front trunk 4 of the middle-fold branch shield 2 serving as a branch shield are assembled in the existing tunnel 1, and the existing tunnel The start entrance 6 is attached to the 1 start pit 5 position.

  Furthermore, a reaction force receiving stand 19 that receives the reaction force of the bent jack 18 that is a propulsion jack is provided behind the front body portion 4.

  The cutter 3 includes a cutter rotating shaft 7 and a cutter pork 9 having a plurality of cutter bits 8 on the front surface. The cutter 3 is manufactured outside the existing tunnel 1 such as a factory, and is carried in from a vertical shaft (not shown) in an integrated state, and a starting pit 5 in the existing tunnel 1 is formed by a carriage (not shown). It is conveyed to the side of the wall surface.

  The front body 4 is divided into a first front body 11 and a second front body 12 from the front side. After the first front body 11 is assembled to the rear part of the cutter 3, Assemble the front torso 12. In addition, the front trunk | drum 4 does not need to be divided | segmented, if conveyance and an assembly are possible integrally.

  The departure entrance 6 is formed in a cylindrical shape that covers the outer periphery of the starting folded folding shield 2, and the cylindrical entrance seal 14 that introduces the folded folding shield 2, and this entrance seal 14 is connected to the existing tunnel 1. And a receiving member 15 connected to the inner wall surface. A seal member 16 is provided on the inner peripheral surface of the entrance seal 14 so as to partition the inside and outside of the existing tunnel 1 when the half-folded branch shield 2 starts. A support member 17 that supports the load of the folded branch shield 2 is provided at the lower part of the inner peripheral surface of the entrance seal 14. In addition, when the shape of the branch shield to cover is non-circular, the start entrance 6 is formed in a non-circular cylindrical shape according to the shape.

  The reaction force cradle 19 is provided further rearward than the assembly space 21 of the middle folding shield 2 behind the front trunk 4, and is fixed to the inner wall surface 22 of the existing tunnel 1.

  After the assembly of the front body portion 4 is completed, as shown in FIG. 2, a shoe 23 is attached to the rear end of the bent jack 18, and a reaction force receiving block 24 is provided between the shoe 23 and the reaction force support 19. . The reaction force receiving block 24 has a length equivalent to the stroke of the bent jack 18. Then, the bent jack 18 is brought into contact with the reaction force receiving block 24 via the shoe 23 and propelled for a predetermined distance. When the half-folded jack 18 has been extended by approximately a stroke, the middle-folded jack 18 is sequentially retracted, and a new reaction force receiving block 24 is provided between the retracted middle folded jack 18 and the reaction force receiving block 24 behind it. The propulsive force of the branch shield 2 is obtained.

  After the cutter 3 and the front body 4 have entered the start entrance 6 with the propulsive force, the cutter 3 is moved from the start tunnel 5 to the outside of the existing tunnel 1 by the propulsive force while rotating the cutter 3. Start off. And it stops when it starts until the rear-end part of the front trunk | drum 4 is located in the rear-end part vicinity of the start opening entrance 6. FIG.

  Thereafter, a load receiving member 25 that supports the front body portion 4 in the axial direction by locking the front body portion 4 from the rear is attached to the rear end portion of the departure entrance 6 (see FIG. 3). The load receiving member 25 is for supporting an earth pressure load transmitted from the cutter 3 to the front body portion 4.

  As shown in FIGS. 5 to 8, a plurality of load receiving members 25 are provided at the rear end of the start entrance 6 along the circumferential direction thereof. The load receiving member 25 is formed in an L shape when viewed from the side, and a fixing portion 26 that is fixed to the rear end surface of the start entrance 6 and a locking portion that engages with the rear end portion of the front trunk portion 4. 27. The fixing portion 26 and the locking portion 27 are integrally formed by bending the plate, and are in surface contact with the rear end surface of the start entrance 6 and the rear end portion of the front body portion 4 respectively. . A reinforcing plate 28 is provided on the fixing portion 26 and the locking portion 27. The reinforcing plate 28 is provided in a direction orthogonal to the fixing plate 26 and the locking plate 27 and serves as a reinforcing rib. A through hole 29 is formed in the fixing portion 26 and is detachably fixed to the rear end surface of the start entrance 6 by a fixing means 31 such as a bolt.

  When the rear end portion of the front body portion 4 is supported by the start opening entrance 6 via the load receiving member 25, the load receiving member 25 and the front body portion 4 are interposed between the load receiving member 25 and the start opening entrance 6. An interval adjusting member 32 such as a shim is provided on either or both sides (both in the present embodiment). The interval adjusting member 32 is selectively attached to the plurality of load receiving members 25 and adjusts the starting direction of the middle-folded branch shield 2 in advance.

  For example, when the folded folding shield 2 is started obliquely downward, a distance adjusting member 32 is provided between the load receiving member 25 located at the upper part and the front body part 4, and The support position is pushed forward in the digging direction from the support position on the lower side of the front barrel portion 4, and the front barrel portion 4 is inclined obliquely downward. Alternatively, a space adjustment member 32 is provided between the load receiving member 25 located at the lower portion and the start entrance 6 and the lower load receiving member is shifted rearward in the starting direction, thereby supporting the lower side of the front body 4. The position is shifted rearward in the digging direction with respect to the support position on the upper side of the front barrel portion 4, and the front barrel portion 4 is inclined obliquely downward.

  Further, a distance adjusting member 32 is provided between the load receiving member 25 and the start entrance 6 and between the load receiving member 25 and the front body portion 4, and the front body portion is provided with a difference in thickness. The angle at which 4 is supported may be adjusted.

  In addition, since the through hole 37 is formed in the space | interval adjustment member 32 provided between the load receiving member 25 and the start opening 6 and the fixing means 31 is inserted in the through hole 37, the space | interval adjustment member 32 itself Can be supported by the fixing means 31. Therefore, the relatively thick gap adjusting member 32 can be inserted. On the other hand, the interval adjusting member 32 provided between the load receiving member 25 and the front body portion 4 is not formed with a through hole, and is fixed by being sandwiched between the load receiving member 25 and the front body portion 4. Therefore, the interval adjusting member 32 having a relatively small thickness is used. In this case, even after the load receiving member 25 is fixed, the interval adjusting member 32 can be increased or decreased relatively easily by loosening the fixing means 31.

  In the above-described embodiment, the distance adjusting member 32 is selectively provided on the load receiving member 25 so that only the upper side or only the lower side is provided, thereby adjusting the digging direction of the middle-folded branch shield 2. However, the present invention is not limited to this, and all load receiving members may be provided with shims, and the thickness or number of the shims may be adjusted to change the direction of the half-branch shield.

  As described above, after the rear end portion of the front body portion 4 is supported by the load receiving member 25, the bent jack 18 is retracted and the reaction force receiving block 24 is removed. Then, as shown in FIG. 3, the rear trunk | drum 33 is conveyed to the assembly space 21 behind the front trunk | drum 4, and it assembles as shown in FIG. 3 and 4, the insertion portion 35 including the spherical portion 34 to be inserted into the front barrel portion 4 of the rear barrel portion 33 is assembled. A shoe 36 is provided on the inner side of the insertion portion 35 and is connected to the tip of the bent jack 18.

  Thereafter, the remaining portion (not shown) of the rear body portion 33 is sequentially carried in and assembled. When the assembly of the half-folded branch shield 2 is completed, a propulsive force is obtained by a propulsion jack (not shown) in the rear trunk portion 33, and the middle-folded branch shield 2 is started.

  As described above, according to the above-described embodiment, the load receiving member 25 is locked using the hollow portion 38 of the spherical bearing of the half-folded branch shield 2 formed at the rear end of the front barrel portion 4. Therefore, unlike the prior art, there is no need to weld the connecting member (see FIG. 9) 56 to the outer peripheral surface of the folded bent shield 2. In addition to this, the load receiving member 25 is detachably provided at the rear end portion of the start entrance 6 with a fixing means such as a bolt, so that it is not necessary to perform welding work or gas cutting, and the folded folding shield The labor and time required for fixing 2 can be greatly reduced.

  Further, by selectively providing the interval adjusting members 32 such as shims on the plurality of load receiving members 25, the load receiving member 25 provided with the interval adjusting members 32 is selected, and the thickness and number of the interval adjusting members 25 are set. With an easy operation such as determination and provision, fine adjustment of the direction of digging of the folded and broken shield 2 can be performed in advance. Therefore, it becomes possible to start the half-folded branch shield 2 in the correct direction, and the construction accuracy is greatly improved.

  In the above-described embodiment, the middle-folded branch shield 2 is described as an example of the branch shield. However, the present invention is not limited to this as long as it has a front trunk portion and a rear trunk portion. For example, the present invention can also be applied to a simultaneous excavation shield in which the front body portion is provided so as to be capable of digging with respect to the rear body portion.

It is the sectional side view which showed the 1st process of the start method of the branch shield which concerns on this invention. It is the sectional side view which showed the 2nd process of the start method of the branch shield which concerns on this invention. It is the sectional side view which showed the 3rd process of the start method of the branch shield which concerns on this invention. It is the sectional side view which showed the 4th process of the start method of the branch shield which concerns on this invention. It is the rear view which showed the support state of the front trunk | drum part of a branch shield. It is the expanded sectional view which showed the starting opening and the load receiving member. It is the expanded rear view which showed the load receiving member. It is the perspective view which showed the load receiving member. It is the sectional side view which showed the process of the starting method of the conventional branch shield.

Explanation of symbols

1 Existing tunnel 2 Middle-folded branch shield (branch shield)
3 Cutter 4 Front trunk 5 Start pit 6 Start entrance 18 Bent jack (propulsion jack)
DESCRIPTION OF SYMBOLS 19 Reaction force stand 24 Reaction force receiving block 25 Load receiving member 27 Locking part 31 Fixing means 32 Space | interval adjustment member 33 Back trunk part

Claims (5)

In a branch shield start method for assembling and starting a branch shield having a cutter, a front trunk section, a rear trunk section, and a propulsion jack spanned between the front trunk section and the rear trunk section in an existing tunnel,
After assembling the cutter of the branch shield and the front trunk in the existing tunnel, attaching a launch entrance to the launch tunnel entrance position of the existing tunnel, and allowing the cutter and front trunk to enter the launch entrance The propulsion force of the propulsion jack causes the cutter to start out of the existing tunnel from the starting tunnel and start until the rear end of the front trunk is located near the rear end of the starting entrance. At the rear end of the entrance entrance, a load receiving member that supports the front body portion in the axial direction by locking the front body portion from the rear is attached, and then the propulsion jack is retracted, and the rear portion behind the front body portion is rearward. A branch shield starting method, wherein the branch shield is started after assembling the trunk portion.   The load receiving member has a locking portion that engages with a rear end portion of the front body portion, and a plurality of load receiving members are detachably fixed to a rear end of the start port entrance by fixing means along a circumferential direction thereof. The branch shield start method according to claim 1.   When the rear end portion of the front body portion is supported by the start opening entrance via the load receiving member, the load receiving member and the start opening entrance are interposed between the load receiving member and the front body portion. The start method of the branch shield of Claim 1 or 2 which provides a space | interval adjustment member in both or any of these, and adjusts the start direction of the said branch shield in advance.   For propulsion by the propulsion jack, a reaction force receiving stand for receiving the reaction force of the propulsion jack is provided in the existing tunnel behind the front trunk portion, and the reaction force receiving base is provided between the reaction force receiving stand and the propulsion jack. This is done by providing a block, bringing the propulsion jack into contact with the reaction force receiving block and propelling it for a predetermined distance, then sequentially retracting the propulsion jack and adding the reaction force receiving block behind the propulsion jack. The branch shield start method according to claim 1. The start of the branch shield according to any one of claims 1 to 4, wherein the branch shield is a middle-folded branch shield in which a front trunk portion and a rear trunk portion are connected to bendable, and the propulsion jack is a middle-fold jack. Method.

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