JP4448405B2 - RC segment, check boring method and core boring method using this RC segment - Google Patents

Description

  The present invention relates to an RC segment for check boring, a check boring method performed on the RC segment for check boring after assembling the segment ring, and a core boring method performed using the RC segment.

  In recent years, the shield method is used in tunnel construction in urban areas. In this shield method, a shield excavator excavates a natural ground with a cutter head while taking reaction force from an existing segment, and at the same time assembles a cover body at the tail part of the shield excavator to cover an underground mine. It is going. For this lining body, RC segments are often used in consideration of durability and price.

In the shield method, after the segments are assembled in the mine, it is necessary to confirm the backfill injection thickness by core boring, etc., and to confirm the tunnel linearity by check boring. Conventionally, core boring for confirming the backfill injection thickness is performed by core boring from the backfill injection hole provided in the segment from inside the tunnel pit and collecting a sample. In addition, the check boring for the linear confirmation of the tunnel is performed by either penetrating the casing penetrating from the ground surface into the segment (for example, refer to Patent Document 1) or by boring aiming at the injection hole of the segment. A swing is inserted through the tunnel mine.
Japanese Patent Publication No. 04-35600

  However, when core boring is performed using a conventional injection hole, there is a problem that water flows out into the tunnel mine and leaks after penetrating the sampler. In addition, if check boring is performed with the casing penetrating into the segment, the RC segment rebar is cut by the casing and the strength of the RC segment is reduced, or water leaks after penetrating into the tunnel mine and leaks after penetrating. If the casing that completely penetrates the segment cannot be pulled out, it becomes an obstacle to the subsequent shield excavation. Further, when the check boring is performed using the conventional injection hole, there is a problem that the boring position is limited and it is difficult to pass the swing down with the injection hole having a small diameter.

  An object of the present invention is to perform check boring and core boring without running out and leaking in a shield tunnel using an RC segment.

In order to solve the above problems, the invention described in claim 1 is an RC segment (for example, segment 3) used for tunnel lining as shown in FIGS.
A steel pipe 5 embedded in the inside and outside of the RC segment and having an observation hole 5a communicating with a casing for check boring (for example, the third casing 12);
An injection metal 6 having an injection hole 6a detachably provided in an observation hole 5a of the steel pipe 5;
An injection metal plug 7 detachably provided in an injection hole 6a of the injection metal 6;
A reinforcing reinforcing bar 8a arranged around the steel pipe 5 is provided.

According to the first aspect of the present invention, the injection metal can be attached to and detached from the observation hole of the steel pipe embedded in the RC segment, and the injection metal plug is attached to and detached from the injection hole of the injection metal. Therefore, it is possible to prevent water leakage from the injection hole by attaching the injection metal plug.
Moreover, by removing the injection metal from the steel pipe, the insertion hole for the downward swing suspended from the ground surface for surveying after the check boring becomes large, and the downward swing can be easily inserted into the tunnel mine.
Furthermore, since the position and angle of the steel pipe after assembling the segment ring can be adjusted freely corresponding to the casing for check boring when forming the RC segment, the degree of freedom in selecting the position of the check boring is improved. .
In addition, even if the check boring casing reaches the RC segment and impacts or penetrates the RC segment, the strength of the RC segment is prevented from being reduced by the reinforcing reinforcing bars arranged around the casing reaching point. be able to.

The invention according to claim 2 is a check boring method for linear confirmation of a tunnel using the RC segment according to claim 1, for example as shown in FIG.
The tip of a casing (for example, the third casing 12) penetrating from the ground surface is bitten into the RC segment,
Then, an injection material (for example, cement 13) is injected into the lower end 12b of the casing,
Drilling is performed from the inside of the tunnel hole of the observation hole 5a of the steel pipe 5, and surveying is performed after the observation hole 5a is communicated with the inside of the casing.

  According to the invention described in claim 2, after the check boring casing is bitten into the outer surface of the RC segment without penetrating the RC segment, the injection material is injected into the lower end of the casing to ensure water-stopping, Since the casing and the tunnel tunnel are communicated with each other by drilling from the tunnel tunnel, it is possible to prevent the RC segment from leaking water and leaking into the tunnel.

The invention according to claim 3 is the check boring method according to claim 2, for example, as shown in FIG. 6, wherein the casing has an upper end portion 12 a and a lower end portion 12 b that are separably connected by a rotating operation. And
After the surveying is finished, the upper end portion 12a of the penetrated casing is pulled out from the ground.

  According to the third aspect of the present invention, the upper end portion and the lower end portion of the casing can be separated by rotating operation. Therefore, after the surveying of the tunnel is finished, the upper end portion of the casing is removed from the lower end portion, and the upper end portion is grounded. Can be pulled out from inside. Therefore, it can prevent that a casing becomes an obstruction of the following shield which passes the underground above steel pipes.

The invention according to claim 4 is the check boring method according to claim 2 or 3, as shown in FIG. 6, for example, and penetrates the first casing (for example, the first casing 10) from the ground surface,
The second and subsequent casings having a small diameter and a long length (for example, the second casing 11) are inserted therein,
The last casing (for example, the third casing 12) is made to reach the RC segment.

  According to invention of Claim 4, after penetrating the 1st casing from the ground surface in the vertical direction, since the second and subsequent casings having a small diameter and long length are penetrated in the vertical direction, The penetrated casing becomes a guide for the casing that penetrates later, and the casing can be accurately penetrated in a predetermined direction.

The invention according to claim 5 is a core boring method for confirming the backfill injection thickness of a tunnel using the RC segment according to claim 1, for example as shown in FIG. 1 and FIG.
After the injection metal fitting 6 is removed, a valve 15 is attached to the observation hole 5a of the steel pipe 5, a water stop 16 is attached below the valve 15, and a sampler 9b is inserted to collect a sample. And

According to the invention described in claim 5, the check boring and the core boring can be performed at the same location of the RC segment. Therefore, since the number of holes provided in the RC segment can be minimized, it is not necessary to perform an operation of providing holes in the RC segment, and a decrease in strength of the RC segment can be prevented.
In addition, since a valve is attached to the observation hole of the steel pipe and a water stop is attached to the valve to penetrate the sampler, water discharge due to core boring can be prevented.

  According to the present invention, the injection metal can be attached to and detached from the observation hole of the steel pipe embedded in the RC segment, and the injection metal plug can be attached to and detached from the injection hole of the injection metal. Therefore, it is possible to prevent water from leaking from the injection hole and water leakage. Moreover, since the casing for check boring bites into the outer surface without penetrating the RC segment, it is possible to prevent the RC segment from flowing out and leaking.

Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to the drawings.
As shown in FIG. 1, the segment ring 1 of the shield tunnel in this embodiment is configured by combining three A-type segments 2, two B-type segments 3, and one K-type segment 4. Since there are water and gas buried pipes on the center line of the segment ring 1, the steel pipe 5 is buried in one side of the B type segment 3, and the B type segment 3 where the steel pipe 5 is not buried is designated as the B1 type segment 3a, The B-type segment 3 in which the steel pipe 5 is embedded is referred to as a B2-type segment 3b.

  As shown in FIGS. 2 to 5, the B2 type segment 3 b according to the present invention includes a steel pipe 5, an injection metal 6, an injection metal plug 7, and a reinforcing reinforcing bar 8 a.

  As shown in FIG. 1 and FIG. 2 (a), the cylindrical steel pipe 5 is embedded in the vertical direction at the location where the third casing 12 reaches when the segment ring 1 is assembled. An annular rubber packing 5b for water stop is fixedly provided on the outer periphery. As shown in FIG. 3, the steel pipe 5 has an observation hole 5a, and a screw groove is formed in a spiral on one end side of the inner surface of the observation hole 5a.

  As shown in FIG. 4, the injection metal 6 is formed from steel and has an injection hole 6a. Moreover, the screw groove is formed in the outer periphery of the injection metal 6 spirally, and the steel pipe 5 and the injection metal 6 can be attached or detached by rotating operation. Further, a screw groove is also formed in a spiral on the inner surface of the injection hole 6a.

  As shown in FIG. 5, the injection metal plug 7 is molded from a synthetic resin, and has a cylindrical screw portion 7b and a lid portion 7c having a diameter larger than that of the screw portion 7b and flat on one end surface thereof. . A screw groove is spirally formed on the outer periphery of the screw portion 7b, and the injection metal piece 6 and the injection metal plug 7 can be attached and detached by a rotating operation. Further, an annular rubber packing 7a for water stop is fitted to a boundary portion between the screw portion 7b and the lid portion 7c.

  When the B2 type segment 3b in which the steel pipe 5 is embedded is molded, the injection metal piece 6 on which the steel lid 6b is placed is screwed into the steel pipe 5, and the injection metal plug 7 is screwed into the injection metal piece 6. Are combined. Further, as shown in FIG. 3, in order to prevent the injected material to be injected back into the observation hole 5a of the steel pipe 5, the mortar 17 is placed in the observation hole 5a of the steel pipe 5. Further, a steel lid 5 is placed on the injection metal 6 in order to prevent the mortar 17 from entering the injection hole 6 a of the injection metal 6.

  Further, as shown in FIG. 2C, the reinforcing reinforcing bars 8a are arranged so as to form a rectangle and a rhombus around the observation hole 5a, and reinforce the conventional reinforcing bars 8.

  Next, a check boring method and a core boring method using the B2 type segment 3b configured as described above will be described.

  First, tunnel excavation is performed by a shield excavator, and the segment ring 1 is assembled as shown in FIG. In the present embodiment, since there is a buried pipe on the center line of the segment ring 1, the third casing 12 reaches a position slightly shifted from the center of the segment ring 1, and is made of steel in a vertical direction at a position corresponding to this. The pipe 5 is buried.

  At the time of assembling the segment ring 1, the injection metal 6 on which the steel lid 6 b is placed is screwed into the steel pipe 5, the injection metal plug 7 is screwed into the injection metal 6, and the observation that the steel pipe 5 has. A mortar 17 is filled in the hole 5a. The mortar 17 prevents the injected material that has been back-filled simultaneously with tunnel excavation from entering the observation hole 5a.

  After the segment ring 1 is assembled, the injection metal 6 and the steel lid 6b are removed from the observation hole 5a, and one end of a linear valve 15 made of steel is screwed into the screw portion 5c of the observation hole 5a. The water stop 16 is screwed to the other end of 15. Thereafter, as shown in FIG. 6A, a sampler 9a is attached to the tip of the small hole drilling machine 9, core boring is performed through the valve 15 and the water stop 16, and the back injection thickness is confirmed from the collected sample. . After sampling, the valve 15 remains and the water stop 16 is removed from the valve 15.

  In addition, when performing core boring and drilling from the tunnel pit, a waste soil transporter such as Zuritro 14 may be installed below the small drilling machine 9.

  Next, as shown in FIG. 6 (b), a first casing 10 having a drilling bit (not shown) provided at the end edge is penetrated from the ground surface by a rotary boring machine (not shown). Penetration is performed while injecting a ground stabilizer such as bentonite from a tube (not shown).

  Next, as shown in FIG. 6C, the second casing 11 having a smaller diameter and longer than the first casing 10 is inserted into the first casing 10 from the ground surface by a rotary boring machine. The excavation bit is provided in the front-end edge part of the 2nd casing 11, and penetration is performed inject | pouring ground stabilizers, such as bentonite, from a tube.

  As shown in FIG. 6 (d), the third casing 12, which has a smaller diameter and longer than the second casing 11 and whose upper end portion 12 a and lower end portion 12 b can be separated by a screw mechanism, It penetrates from the surface by a rotary boring machine. The excavation bit is provided in the front-end edge part of the 3rd casing 12, and penetration is performed inject | pouring ground stabilizers, such as a bentonite, from a tube. And after the 3rd casing 12 arrives at the B2 type segment 3b, the front-end | tip part of the 3rd casing 12 is made to bite into the B2 type segment 3b outer surface.

  Thereafter, as shown in FIG. 6 (e), the cement 13 is pumped from a tube (not shown) connected to a pump (not shown) to the inside of the lower end portion 12b of the third casing 12 and the B2 type segment 3b. Consolidate in the enclosed area.

  When the cement 13 is sufficiently solidified, as shown in FIG. 6 (f), a water stop 16 is screwed into the valve 15, and a drilling rod 9 b is attached to the tip of the small drilling machine 9. The cement 13 is drilled through the vessel 16, and the third casing 12 and the tunnel mine are communicated.

And after pulling out the drilling rod 9b and the small drilling machine 9 from the valve 15 and the water stopper 16, the valve 15 and the water stopper 16 are removed from the observation hole 5a, and a downward swing (not shown) is suspended from the ground surface. Then, after setting the reference point in the tunnel mine and carrying out surveying, turn down. Thereafter, the injection metal 6 is immediately attached to the observation hole 5a, and the injection metal plug 7 is screwed into the injection metal 6.
If there is water leakage after the check boring, the injection metal plug 7 may be removed from the injection hole 6a and the injection material may be injected to stop the water.

  And after removing the upper end part 12a of the 3rd casing 12 from the lower end part 12b by rotation operation, only the upper end part 12a is pulled out, filling a mortar, with the lower end part 12b embedded in the ground. Thereafter, the second casing 11 is pulled out while filling with mortar, and similarly, the first casing 10 is pulled out while filling with mortar.

  According to the above embodiment, the injection metal 6 can be attached to and detached from the observation hole 5a of the steel pipe 5 embedded in the B2 type segment 3b, and the injection hole 6a of the injection metal 6 has an injection. Since the metal plug 7 can be attached and detached, it is possible to prevent water leakage from the injection hole 6a by attaching the metal injection plug 7.

Since the position and angle of the steel pipe 5 after assembling the segment ring 1 can be freely adjusted corresponding to the third casing 12 when forming the B2 type segment 3b, the degree of freedom in selecting the position of the check boring is improved. To do.
Further, since the valve 15 is attached to the observation hole 5a of the steel pipe 5 and the water stop 16 is attached to the valve 15 so as to penetrate the sampler 9a, it is possible to prevent water discharge and leakage due to core boring.

After penetrating the first casing 10 in the vertical direction from the ground surface, the second casing 11 having a smaller diameter and longer than the first casing 10 is penetrated in the first casing 10 in the vertical direction, and then from the second casing 11. The third casing 12 having a small diameter and a long length penetrates into the second casing 11 in the vertical direction. Accordingly, the first casing 10 serves as a guide when the second casing 11 and the second casing 11 penetrate the third casing 12, and the third casing 12 can be reliably penetrated in a predetermined direction.
In addition, the third casing 12 is bitten into the outer surface without penetrating the B2 type segment 3b, and then the cement 13 is injected into the lower end portion 12b of the third casing 12 to ensure water stoppage. Since the third casing 12 and the tunnel mine are communicated with each other by the drilling holes, it is possible to prevent water discharge and leakage from the B2 type segment 3b to the mine.

Even if the third casing 12 reaches the B2 type segment 3b and gives an impact to or penetrates the B2 type segment 3b, the reinforcing reinforcing bar 8a arranged around the arrival point of the third casing 12 causes the B2 type segment. The strength reduction of 3b can be prevented.
Moreover, since the upper end part 12a and the lower end part 12b of the 3rd casing 12 can be isolate | separated by the screw mechanism, the upper end part 12a can be pulled out from the ground after completion | finish of surveying of a tunnel. Therefore, it can prevent that the 1st casing 10, the 2nd casing 11, and the 3rd casing 12 upper end part 12b obstruct | occlude the subsequent shield which passes the underground above the steel pipes 5. FIG.

By removing the injection hardware 6 from the steel pipe 5, the insertion hole for the downward swing suspended from the ground surface for surveying after the check boring becomes large, and the downward swing can be easily inserted.
Also, the check boring and the core boring for confirming the backfill injection thickness can be performed at the same location of the B2 type segment 3b. Therefore, since the number of holes provided in the B2 type segment 3b can be minimized, it is not necessary to perform an operation of providing holes in the B2 type segment 3b, and a decrease in strength of the B2 type segment 3b can be prevented.

In the above embodiment, the steel pipe is embedded in the B-type segment, but the present invention is not limited to this and may be embedded in the A-type segment or the K-type segment.
Further, the number of casings, the type of injection material, the reinforcing bar arrangement structure, and the like are arbitrary, and it is needless to say that other specific detailed structures can be appropriately changed.

It is a schematic sectional drawing which shows the segment ring by RC segment which concerns on this invention. BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic structure figure which shows RC segment based on this invention, A cross-sectional structure figure (a), The upper half is an outer diameter side, the lower half is an inner diameter side cross-section structure figure (b), ). It is sectional drawing which shows the steel pipe of the RC segment concerning this invention. It is sectional drawing which shows the injection metal of the RC segment which concerns on this invention. It is sectional drawing which shows the injection metal plug of the RC segment concerning this invention. It is a schematic sectional drawing which shows the work process of the check boring which concerns on this invention, at the time of core boring for an injection hole thickness confirmation (a), the 1st casing penetration (b), the 2nd casing penetration (c), 3rd When the casing penetrates (d), when cement is pumped (e), and when drilling cement (f).

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Segment ring 2 A type segment 3 B type segment 3a B1 type segment 3b B2 type segment 4 K type segment 5 Steel pipe 5a Observation hole 5b Rubber packing 5c Screw part 6 Injection metal 6a Injection hole 6b Steel lid 7 Injection metal plug 7a Rubber packing 7b Screw part 7c Lid 8 Reinforcing bar 8a Reinforcing bar 9 Small drilling machine 9a Sampler 9b Drilling rod 10 First casing 11 Second casing 12 Third casing 12a Upper end 12b Lower end 12c Opening range 13 Cement 14 Zuritro 15 Valve 16 Water stop 17 Mortar

Claims (5)

In the RC segment used for tunnel lining,
A steel pipe embedded in the inside and outside of the RC segment and having an observation hole communicating with a casing for check boring;
An injection metal fitting having an injection hole detachably provided in the observation hole of the steel pipe;
An injection metal plug detachably provided in an injection hole of the injection metal,
An RC segment comprising reinforcing steel bars arranged around the steel pipe. A check boring method for linear confirmation of a tunnel using the RC segment according to claim 1,
The tip of the casing penetrating from the ground surface is bitten into the RC segment,
Thereafter, an injection material is injected into the lower end of the casing,
A check boring method, wherein drilling is performed from the inside of a tunnel hole of an observation hole of the steel pipe, and surveying is performed after the observation hole and the inside of the casing are communicated. The casing has an upper end and a lower end connected so as to be separable by rotating operation,
3. The check boring method according to claim 2, wherein after the surveying is finished, an upper end portion of the penetrated casing is pulled out from the ground. Penetrate the first casing from the surface,
The second and subsequent casings with a small diameter and a long length are inserted into it,
The check boring method according to claim 2, wherein a last casing is made to reach the RC segment. A core boring method for confirming the backfill injection thickness of a tunnel using the RC segment according to claim 1,
A core boring method characterized in that after removing the injection metal fitting, a valve is attached to an observation hole of the steel pipe, a water stop is attached under the valve, a sampler is inserted, and a sample is collected.

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