JP4557942B2 - Tunnel lining concrete placement method and placement structure - Google Patents

Description

  The present invention relates to a tunnel lining concrete placing method for forming lining concrete using a tunnel lining formwork, and a tunnel lining concrete placing structure used for the lining concrete placing method.

  For example, in tunnel construction methods such as the mountain tunnel construction method, a tunnel lining formwork (concrete lining mold is used as a method for forming tunnel lining concrete that is constructed to cover the natural ground on the inner peripheral surface of the excavated tunnel. A method using a frame is generally employed. As shown in FIGS. 9 (a) and 9 (b), the tunnel lining formwork 50 is formed on the side wall of the tunnel 53 along the inner peripheral surface 54 of the tunnel 53 having a shape including an arch-shaped portion 52 such as a horseshoe shape. In the space 61 between the installed tunnel lining form 50 and the natural ground covered with the sprayed concrete 56 on the inner peripheral surface 54 of the tunnel 53 The lining concrete is formed so as to be continuous with the concrete of the inverted portion 51 at the bottom of the tunnel, preferably by placing and hardening unreinforced concrete.

  Moreover, as the tunnel lining formwork 50, for example, in addition to the assembly type tunnel lining formwork called paracentle, a mobile tunnel lining formwork called slide centle is known. With the progress of the excavation work, the tunnel lining formwork 50 is moved from the rear to the front in the digging direction of the tunnel 53 while the tunnel lining formwork 50 is reinstalled every predetermined span of about 10 m, for example. Then, the side and upper lining concrete of the tunnel 53 is sequentially cast and formed.

  And in order to cast the lining concrete of the side part and the upper part of the tunnel using the tunnel lining formwork 50, for example, as shown in FIGS. For example, an area from the side wall portion 55 of the tunnel 53 to the shoulder portion of the arch-shaped portion 52 is provided through the inspection window 56 as a height region where concrete can be placed from the inspection window 56 provided in the mold 50. The concrete 57 is supplied and the vibrator 58 is inserted from the inspection window 56, and the concrete 57 is placed while the supplied concrete 57 is compacted. After that, as a height region that is difficult to be compacted by the vibrator 58 while supplying the concrete 57 from the inspection window 56, the tunnel 53 (see FIG. 9) region of the tunnel 53 is referred to as a tunnel region. A pattern is used in which concrete is driven in by a blow-up method from a concrete casting hole 60 as a blow-up opening provided at the top end of the lining mold 50 and the concrete 57 of the crown 59 is formed without compaction. ing.

  More specifically, after the tunnel lining formwork 50 is installed at a predetermined position, for example, the concrete 57 is poured from the lower portion of the side wall portion 55 through the lower inspection window 56 and compacted using the vibrator 58. (See FIG. 10 (a)), and further, a step of compacting using the vibrator 58 while pouring the concrete 57 through the middle inspection window 56 toward the arch-shaped portion 52 at the upper part of the side wall 55 (FIG. 10 ( b)), and further to the front of the crown 59 of the arch-shaped portion 52, the concrete 57 is poured through the upper inspection window 56 and, if necessary, the concrete placement hole 60, and then compacted using the vibrator 58. The process (see FIG. 10C) and the concrete from the portion on the existing lining concrete 62 side of the crown portion 59 through the concrete placement hole 60 in order. It poured over preparative 57, by a step of filling concrete to wife formwork 63 without compaction (see FIG. 10 (d)), so that the lining concrete is pouring.

  With the conventional method for placing lining concrete using the tunnel lining formwork 50 as described above, the concrete 57 placed on the tunnel crown (crown) 59 cannot be compacted. The reliability of the lining concrete at the crown portion 59 is lowered, and in the vicinity of the existing lining concrete 62, air accumulation and cavities are likely to occur. Further, since the concrete 57 is placed in the space 61 between the tunnel lining formwork 50 and the natural ground in a concentrated manner from the concrete placing hole 60 as a blow-up opening, the concrete 57 is removed from the concrete placing hole 60. The trajectory when flowing to the surroundings tends to remain on the surface of the lining concrete as a striped pattern, resulting in poor finish.

On the other hand, a technique is disclosed that enables the concrete placed in the tunnel crown to be compacted (see, for example, Patent Document 1). In the lining concrete placement method of Patent Document 1, when a tunnel is constructed by a shield method different from the mountain tunnel method, the crown portion of the gap between the segment and the centle extends over substantially the entire length in the tunnel axis direction. An extending guide rail with an L-shaped angle suspended in a concave direction and a rod-shaped vibrator that moves along the guide rail are installed, and concrete is placed in the gap in the crown portion from the existing side with a rod-shaped vibrator. It was cast while compacted, and the rod-shaped vibrator was moved along the guide rail from the existing side toward the end plate side as the concrete was filled. Moreover, in the lining concrete placement method of patent document 1, a guide rail is provided also as a setup line of secondary lining concrete, for example.
JP 2002-30893 A

  However, in the method of placing concrete on the crown portion of the tunnel described in Patent Document 1, a guide rail having an L-shaped angle that guides the rod-like vibrator in the tunnel axial direction is used as the burying member left in the concrete. Since it is necessary to provide the entire length of the tunnel in the axial direction of the tunnel in advance, the lining concrete is preferably formed by using unreinforced concrete without installing a setup bar or the like. In a mountain tunnel or the like using a tunnel lining formwork, a lot of waste is caused in its materials and construction.

  Further, in the placing method described in Patent Document 1, for example, the concrete placed newly is tightened each time the rod-like vibrator is moved while changing the position of the concrete placing hole for supplying the concrete to the gap in the crown portion. When solidifying, the length of the vibrator cable embedded in the concrete is not so long, and it is easy to move the rod-like vibrator while pulling the vibrator cable. However, for example, after filling concrete in the entire gap of the crown portion at the concrete placement site, and then placing the rod-shaped vibrator disposed in the vicinity of the existing lining concrete, the rod-like vibrator is provided over substantially the entire length of the placement site. When the concrete is compacted by moving it while pulling it to the side of the end plate via the vibrator cable embedded in the concrete, a large frictional force (adhesive force) is generated between the vibrator cable and the concrete. As a result, the pulling resistance at the time of towing becomes excessive, and the rod-like vibrator cannot be moved, or the vibrator cable may be broken or damaged.

  The present invention has been made paying attention to such a conventional problem, and is formed using a tunnel lining formwork with a simple configuration without causing much waste in materials and construction. It is possible to efficiently and effectively compact the lining concrete at the crown of the tunnel, and even when the concrete is compacted with a rod-shaped vibrator after filling the concrete over the entire length of the lining space, the vibrator cable can be An object of the present invention is to provide a tunnel lining concrete placing method and a tunnel lining concrete placing structure capable of effectively suppressing a pulling resistance when pulling to the frame side and moving a rod-shaped vibrator smoothly. .

  The present invention provides a tunnel lining concrete placement method for forming lining concrete using a tunnel lining formwork, wherein the tunnel covering is sandwiched between the end face of the already formed lining concrete and the end formwork. The lining space between the outer peripheral surface of the work form and the inner lining surface of the tunnel consists of a plurality of hollow pipes with different outer diameters. The hollow pipe with the smaller outer diameter is replaced with the hollow pipe with the larger outer diameter. A multi-stage hollow pipe that was slidably inserted into the pipe to expand and contract the entire length, and the hollow pipe with the smaller outer diameter was placed on the existing lining concrete side and extended in the axial direction of the tunnel A vibrator that is attached in a state and is disposed so as to protrude from the end of the existing lining concrete side of the multistage hollow pipe, and that follows the rear end portion of the vibrator. A cable is inserted into the multi-stage hollow pipe so as to extend toward the end form frame, and is arranged to penetrate the end form frame so that it can be pulled from the outside of the end form frame. Concrete is placed and filled, and the vibrator cable is pulled while vibrating the rod-like vibrator, and the vibrator cable is locked with the rod-like vibrator protruding to the first hollow pipe having the smallest outer diameter. Then, the first hollow pipe is inserted into the second hollow pipe having the next largest outer diameter until the first hollow pipe is locked to the second hollow pipe, and the vibrator cable is further pulled. The second hollow pipe into which the first hollow pipe is inserted is locked to a third hollow pipe having the next largest outer diameter, and the second hollow pipe is locked to the third hollow pipe. The concrete filled and laid in the lining space is inserted into the hollow pipe having the smaller outer diameter into the hollow pipe having the larger outer diameter while the multistage hollow pipe is contracted. The above object is achieved by providing a tunnel lining concrete placing method that compacts the existing lining concrete side portion toward the end formwork side.

  Further, according to the tunnel lining concrete placing method of the present invention, the vibrator cable is a state in which the rod-like vibrator is protruded linearly from an end portion on the existing lining concrete side of the multistage hollow pipe, It is preferable that the base end portion of the first hollow pipe on the second hollow pipe side is locked to the first hollow pipe.

  Furthermore, according to the tunnel lining concrete placing method of the present invention, it is preferable that the lining space is a lining space of a tunnel crown.

  And this invention is the tunnel lining concrete placement structure used for the said tunnel lining concrete placement method, Comprising: The said tunnel lining which is pinched | interposed by the end surface of the existing lining concrete and the end formwork The lining space between the outer periphery of the formwork and the inner lining of the tunnel is composed of a plurality of hollow pipes with different outer diameters, and the hollow pipe with the smaller outer diameter is replaced with the hollow pipe with the larger outer diameter. A multi-stage hollow pipe that can be sequentially slidably inserted into the tube to expand and contract the entire length, and the hollow pipe with the smaller outer diameter is placed on the existing lining concrete side and extended in the axial direction of the tunnel And a vibrator that protrudes from the end of the existing lining concrete side of the multistage hollow pipe and follows the rear end portion of the vibrator A cable is inserted into the multi-stage hollow pipe so as to extend toward the end formwork side, and is disposed through the end formwork so as to be pulled from the outside of the end formwork. The above object is achieved by providing a structure.

  According to the tunnel lining concrete placing method or the tunnel lining concrete placing structure of the present invention, it is formed using a tunnel lining formwork with a simple configuration without causing much waste in materials and construction. In particular, the lining concrete of the tunnel crown can be compacted efficiently and effectively, and the vibrator cable can be used even when the concrete is compacted with a rod-shaped vibrator after filling and placing the concrete over the entire length of the lining space. The rod-like vibrator can be moved smoothly by effectively suppressing the pull-out resistance when pulling toward the end form frame.

  As shown in FIGS. 1A to 1C, a tunnel lining concrete placing method according to a preferred embodiment of the present invention is for tunnel lining as a concrete lining formwork, for example, in a mountain tunnel construction method. When forming the lining concrete 11 on the side and the upper part of the tunnel 12 using the mold 10, in particular, the lining concrete 11a of the crown (crown) 13 of the tunnel 12 is placed below this. For example, it is employed as a method for placing the lining concrete 11 on the side wall portion and the arch-shaped portion of the tunnel 12 and then placing it while sufficiently compacting.

  Here, in this embodiment, the tunnel lining form 10 is, for example, a slide-movable centle known as the prior art, and a predetermined span of, for example, about 10 m as the tunnel 12 excavates. It is possible to sequentially cast and form the lining concrete 11 on the side portion and the upper portion of the tunnel 12 while re-installing the tunnel 12 from the rear to the front in the digging direction X. Moreover, in this embodiment, the lining concrete 11 of a side wall part and an arch-shaped part is concrete through the inspection window 14 provided in the installed tunnel lining formwork 10 by the method similar to the conventional construction method, for example. Is supplied, and a rod-like vibrator 14a as a vibration compaction device is inserted from the inspection window 14 to compact the supplied concrete, whereby the side wall portion and the arched portion of the lining concrete 11 are tunnel crown portions. It will be placed prior to the 13 lining concrete 11a.

  The tunnel lining concrete placement method of this embodiment is a concrete placement method for forming the lining concrete 11a of the crown portion 13 of the tunnel 12 by using the tunnel lining form 10, which is shown in FIG. As shown in FIG. 2, prior to the concrete placing work, first, the outer peripheral surface of the tunnel lining formwork 10 sandwiched between the end face 15 a of the existing lining concrete 15 and the end formwork 16. And a lining space 23 between the inner periphery of the tunnel and a lining surface 22 of the tunnel, which is composed of a plurality of (three in this embodiment) hollow pipes 17a, 17b, 17c having different outer diameters, and the hollow pipe having the smaller outer diameter. The multi-stage hollow pipe 18 (see FIG. 2) whose outer length can be expanded and contracted by sequentially inserting the 17a and 17b into the hollow pipes 17b and 17c having the larger outer diameter so as to be slidable, The empty pipes 17a and 17b are disposed on the existing lining concrete 15 side and attached in a state extending in the axial direction X of the tunnel 12, and the rod-like vibrator 20 is attached from the end of the multistage hollow pipe 18 on the existing lining concrete 15 side. A vibrator cable 19 which is disposed so as to protrude and which follows the rear end portion of the rod-shaped vibrator 20 is inserted into the multistage hollow pipe 18 so as to extend toward the end form 16 and penetrate the end form 16. A placement structure for placing tunnel lining concrete is installed at the time of assembling the tunnel lining form 10 so that it can be pulled from the outside of the end form 16 by being disposed.

  And in this embodiment, while the above-mentioned tunnel lining concrete placement structure is installed in the crown part 13 of the tunnel 12, while filling concrete in the lining space 23 (refer FIG.1 (c)). 3 to 6, the vibrator cable 19 is pulled while vibrating the rod-shaped vibrator 20, and the vibrator cable 19 is left protruding in the first hollow pipe 17 a having the smallest outer diameter. From the locked state (see FIG. 3), until the first hollow pipe 17a is locked to the second hollow pipe 17b having the next largest outer diameter, and the first hollow pipe 17a is locked to the second hollow pipe 17b. Insert (see FIG. 5). Thereafter, the vibrator cable 19 is further pulled so that the second hollow pipe 17b into which the first hollow pipe 17a is inserted is then transferred to the third hollow pipe 17c having the next larger outer diameter, and the second hollow pipe 17b is connected to the third hollow pipe 17b. Insert until it is locked to the hollow pipe 17c (see FIG. 6). In this way, the concrete 11a filled in the lining space 23 is inserted into the hollow pipes 17b and 17c having the smaller outer diameter sequentially into the hollow pipes 17b and 17c having the larger outer diameter, so that the multistage hollow pipe is inserted. While shrinking 18, the lining concrete 11 a of the crown portion 13 of the tunnel 12 is formed by compacting from the portion on the existing lining concrete 15 side toward the end frame 16 side.

  The multi-stage hollow pipe 18 is a rod-shaped member that can extend and contract by providing a so-called telescopic structure. In the present embodiment, for example, a first hollow pipe 17a made of a steel pipe, a second hollow pipe 17b, And the third hollow pipe 17c. The first hollow pipe 17a is a hollow pipe having the smallest outer diameter. For example, the first hollow pipe 17a has an outer diameter of 5.6 cm and a length of 3.0 m. The first hollow pipe 17a has an inner diameter through which the vibrator cable 19 can be inserted, and a locking projection 26 provided on the vibrator cable 19 with a reduced inner diameter at the proximal end portion on the second hollow pipe 17b side. A locking sleeve 21a for abutting and locking is attached and fixed (see FIG. 4).

  The second hollow pipe 17b is a hollow pipe having the next largest outer diameter after the first hollow pipe 17a. For example, the second hollow pipe 17b has an outer diameter of 6.6 cm and a length of 3.0 m. The second hollow pipe 17b has an inner diameter through which the first hollow pipe 17a can be inserted, and an end of the first hollow pipe 17a with a reduced inner diameter at the base end portion on the third hollow pipe 17c side. A locking sleeve 21b for abutting and locking is attached and fixed (see FIG. 2).

  The third hollow pipe 17b is a hollow pipe having the largest outer diameter. For example, the third hollow pipe 17b has an outer diameter of 7.6 cm and a length of 3.0 m. Further, the third hollow pipe 17b has an inner diameter through which the second hollow pipe 17a can be inserted, and the proximal end portion on the side of the end frame 16 is reduced in inner diameter so that the end of the second hollow pipe 17b is provided. A locking sleeve 21c for contact and locking is mounted and fixed (see FIG. 2).

  The hollow pipes 17a, 17b, and 17c are provided between the first hollow pipe 17a, the second hollow pipe 17b, and the outer peripheral surface of the vibrator cable 19 that are inserted through the inner peripheral surface of the tip portion. For example, a seal ring (not shown) is provided at an appropriate position. Further, when the multi-stage hollow pipe 18 is extended, the hollow pipes 17a, 17b having a smaller outer diameter are externally attached to the outer peripheral surface of the base end portion and the inner peripheral surface of the distal end portion of these hollow pipes 17a, 17b, 17c. For example, stopper protrusions (not shown) for preventing the hollow pipes 17b and 17c having larger diameters from falling off are provided at appropriate positions.

  The rod-like vibrator 20 that is disposed to protrude from the end of the existing lining concrete 15 of the multistage hollow pipe 18 includes, for example, an electromagnetic vibrator, a vibrator that vibrates by the rotational force of a motor, and the like. This is a known device that is widely used as a compacting device, and is configured integrally with a vibrator cable 19 that is connected to the rear end portion of the rod-like vibrator 20 and is composed of a flexible power supply hose containing a conductor or the like.

  As shown in FIG. 7, the vibrator cable 19 covers, for example, a wire 19 a having a thickness of 8 mm with a polyamide tube 19 b having an inner diameter of 9.2 mm and an outer diameter of 12 mm, and a conductor 19 c interposed on the outer peripheral surface of the polyamide tube 19 b. The cords 19d are alternately arranged in the circumferential direction by six pieces, and further covered with a sheath (outer skin) 19e having an outer diameter of 21.8 mm, and then covered with a hydraulic hose 19f. This is a known cable member of 37.2 mm, and the vibrator cable 19 and the hollow pipes 17a, 17b, and 17c embedded in the concrete 11a filled and laid in the lining space 23 are subjected to frictional force with the concrete 11 ( It has a sufficient tensile strength to pull it toward the end form frame 16 together with the rod-shaped vibrator 20 against the adhesive force.

  Further, the vibrator cable 19 protrudes outward from the outer peripheral surface at a position, for example, about 3.0 m corresponding to the length of the first hollow pipe 17a from the connecting portion with the rod-shaped vibrator 20, and a locking projection 26 is formed. For example, it is provided by caulking the vibrator cable 19 (see FIGS. 2 and 4). As shown in FIG. 3, the vibrator cable 19 is pulled so that the locking projection 26 is brought into contact with and locked with a locking sleeve 21a provided at the proximal end portion of the first hollow pipe 17a. However, it will be positioned in the state which protruded linearly from the edge part by the side of the existing lining concrete 15 of the multistage hollow pipe 18. As shown in FIG.

  The vibrator cable 19 can be locked to the multi-stage hollow pipe 18 at the tip of the first hollow pipe 17a to position the rod-shaped vibrator 20 linearly with the multi-stage hollow pipe 18, but as described above. In addition, when the vibrator cable 19 is locked to the first hollow pipe 17a at the base end portion of the first hollow pipe 17a, the first hollow pipe 17a is moved to the end frame 16 side by pulling the vibrator cable 19. In addition, since the compressive force from the front end side is not applied to the first hollow pipe 17a, the first hollow pipe 17a can be moved in a more rational and stable state.

  In this embodiment, the tunnel lining concrete placement structure by the multistage hollow pipe 18 after the lining concrete 11 of the side wall portion and the arch-shaped portion of the tunnel 12 shown in FIG. For example, as shown in FIG. 1C, a concrete pump is connected to the concrete placement hole 24 with respect to the lining space 23 of the crown portion (crown portion) 13 of the tunnel 12. Fill and cast concrete.

  In the present embodiment, in the step of placing the lining concrete 11 on the side wall portion and the arch-shaped portion of the tunnel 12 shown in FIG. 1A, the end of the existing lining concrete side 15 of the multistage hollow pipe 18 is provided. The rod-like vibrator 20 that protrudes from the section is guided downward through a pulley 27 (see FIG. 2) attached to the tunnel lining mold 10, and the vibrator cable 19 is fed out to form a side wall or an arch. By suspending and arranging the rod-like vibrator 20 while pulling the vibrator cable 19 with the rise of the concrete placed on the side wall portion or the arch-shaped portion, the tunnel 12 is suspended. It can also be used for compacting the lining concrete 11 of the side wall and the arch-shaped portion. Further, when the lining concrete 11 on the side wall portion and the arch-shaped portion of the tunnel 12 is finished, for example, the pulley 27 is removed by work from the inspection window provided at the top end portion of the tunnel lining form 10, As shown in FIG. 3, the vibrator cable 19 is pulled, and the rod-like vibrator 20 is arranged so as to be linearly connected to the tip of the multistage hollow pipe 18.

  After filling and placing concrete in the lining space 23 of the crown portion 13 of the tunnel 12, as shown in FIG. 1 (c), additional concrete is placed from the concrete placement hole 24 and other placement openings as required. However, while vibrating the rod-shaped vibrator 20, the rod-shaped vibrator 20 is moved to the end form frame 16 side by pulling the vibrator cable 21 by the pulling force of the cord winding device 25, for example.

  Here, the hollow pipes 17a, 17b, and 17c constituting the multi-stage hollow pipe 18 are embedded in the concrete with substantially the same length, and the first hollow disposed at the tip portion on the existing lining concrete 15 side. The pipe 17a has an outer diameter smaller than that of the other hollow pipes 17b and 17c, and also has a smaller adhesion force to concrete. Therefore, as shown in FIG. Prior to the hollow pipes 17b and 17c, only the first hollow pipe 17a is connected to the second hollow pipe 17b until the end thereof abuts against the locking sleeve 21b of the proximal end portion of the second hollow pipe 17b. It will be inserted.

  When the first hollow pipe 17a is inserted into the second hollow pipe 17b, the vibrator cable 19 is further pulled, and only the second hollow pipe 17b having an outer diameter smaller than that of the third hollow pipe 17c and a small adhesion to concrete. As shown in FIG. 6, this is inserted into the third hollow pipe 17c until its end abuts against the locking sleeve 21c at the base end portion of the third hollow pipe 17c.

  After that, the third hollow pipe 17c in which the second hollow pipe 17b and the first hollow pipe 17a are overlapped and inserted inside is released from the fixed state to, for example, the wife mold 16 and is provided in the wife mold 16 By pulling the vibrator cable 19 through the extraction hole 16a and removing it from the lining space 23 together with the rod-like vibrator 20, the placement work of the lining concrete 11 in the span where the tunnel lining formwork 10 is installed can be performed. finish.

  And according to this embodiment, the covering concrete of the crown portion 13 of the tunnel 12 is formed by using the tunnel covering formwork 10 with a simple configuration without causing much waste in materials and construction. 11a can be efficiently and effectively compacted, and even when the concrete is compacted by the rod-shaped vibrator 20 after filling the concrete over the entire length of the lining space 23, the vibrator cable 19 is connected to the side of the end frame 16 side. It is possible to effectively suppress the pulling resistance at the time of towing, and to smoothly move the rod-shaped vibrator 20.

  That is, in the present embodiment, the multi-stage hollow pipe 18 composed of the first hollow pipe 17a, the second hollow pipe 17b, and the third hollow pipe 17c having different outer diameters, with the rod-shaped vibrator 20 protruding from the tip, is covered. After placing in the space 23 and filling and placing the concrete in the lining space 23, the first hollow pipe 17 a and the second hollow pipe 17 b having a small outer diameter on the existing lining concrete 15 side are pulled by pulling the vibrator cable 21. The rod-shaped vibrator 20 is moved toward the end form 16 while being inserted into the second hollow pipe 17b and the third hollow pipe 17c sequentially, and the concrete is compacted, so that the multi-stage hollow pipe 18 is removed from the lining space 23 in particular. Since it can be reused later, a guide rail such as an L-shaped angle that guides the rod-shaped vibrator can be used as a tunnel lining formwork. Compared with the method of pre-installing over the entire length of the span, it is possible to efficiently compact the lining concrete 11a by a simple method without causing much waste in materials and construction. Become. As a result, it is possible to easily obtain the lining concrete 11a which is sufficiently compacted and has a good quality and a good surface finish.

  Further, according to the present embodiment, the first hollow pipe 17a, the second hollow pipe 17b, and the third hollow pipe 17c that divide the multi-stage hollow pipe 18 into three parts are respectively brought to the end form 16 side by pulling the vibrator cable 21. Since the concrete is compacted by the rod-shaped vibrator 20 at the distal end while being moved, the pulling resistance due to the pulling of the vibrator cable 21 when the hollow pipes 17a, 17b, 17c are moved is not divided and the existing lining concrete 15 is divided. Compared to the case where a hollow pipe or a vibrator cable continuously embedded in the concrete is pulled out at a time, the pulling resistance is, for example, about 1/3. After filling and placing concrete, the concrete is compacted while moving the rod-like vibrator 20 To effectively reduce the pull-out resistance of, it is possible to move the rod-like vibrator 20 smoothly.

Here, when the adhesion force between the concrete and the hollow pipe is fkgf / cm ² , the outer diameter is 5.6 cm and the length is 3.0 m when the pulling resistance force is (peripheral area of each pipe) × (adhesion force). The first hollow pipe 17a has a maximum pulling resistance of 52.8 fkgf / cm ² , an outer diameter of 6.6 cm, and a second hollow pipe 17b having a length of 3.0 m has a maximum pulling resistance of 62.2 fkgf / cm ² . The maximum pulling resistance of the third hollow pipe 17c having a diameter of 7.6 cm and a length of 3.0 m is 71.6 fkgf / cm ² . On the other hand, the maximum pulling-out resistance when the entire hollow pipe 17a having a general outer diameter of 5.6 cm and a length of 9.0 m is embedded in the concrete from the end form is 158.46 fkgf / cm ^2. . Therefore, the pulling resistance due to the pulling of the vibrator cable 21 is greatly reduced by forming the multi-stage hollow pipe 18 by dividing it into the first hollow pipe 17a, the second hollow pipe 17b, and the third hollow pipe 17c. Accordingly, it is confirmed that the rod-shaped vibrator 20 can be smoothly moved in the concrete according to the present embodiment.

  The present invention is not limited to the above-described embodiment, and various modifications can be made. For example, the present invention can be employed to form lining concrete in other tunnels other than mountain tunnels. In addition, the inner peripheral surface of the tunnel that forms a lining space between the outer surface of the tunnel lining formwork is the inner periphery of the tunnel after the primary lining is performed in addition to the ground covered with sprayed concrete. It may be a lining surface for performing secondary lining by a surface. Furthermore, the lining concrete to be compacted according to the present invention is not necessarily the lining concrete of the tunnel crown, for example, a multi-stage hollow pipe is disposed on the side wall, shoulder, arch-shaped part, etc. of the tunnel, The invention can also be applied. Furthermore, the multi-stage hollow pipe is not necessarily a multi-stage hollow pipe composed of three hollow pipes, and may be a multi-stage hollow pipe composed of four or more hollow pipes.

(A)-(c) is the abbreviation which shows the work procedure of the laying concrete placement work including the tunnel lining concrete placement method concerning one desirable embodiment of the present invention, and shows a part as a sectional view It is a side view. It is a schematic sectional drawing explaining one work process of the tunnel lining concrete placement method which concerns on preferable one Embodiment of this invention. It is a schematic sectional drawing explaining one work process of the tunnel lining concrete placement method which concerns on preferable one Embodiment of this invention. FIG. 4 is an enlarged cross-sectional view of a part A in FIG. 3. It is a schematic sectional drawing explaining one work process of the tunnel lining concrete placement method which concerns on preferable one Embodiment of this invention. It is a schematic sectional drawing explaining one work process of the tunnel lining concrete placement method which concerns on preferable one Embodiment of this invention. It is an expanded sectional view of a vibrator cable. It is a chart which compares and shows the maximum drawing-out resistance of the multistage hollow pipe used in the tunnel lining concrete placement method concerning one desirable embodiment of the present invention, and a general hollow pipe. (A) is sectional drawing seen from the tunnel axial direction explaining the state which installed the formwork for concrete lining along the inner peripheral surface of a tunnel, (b) is the same side view. (A)-(d) is a side view which shows the work procedure of the conventional tunnel lining concrete placement method, and shows one part as sectional drawing.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Formwork 11 for tunnel lining Concrete lining concrete 11a Crown lining concrete 12 Tunnel 13 Tunnel crown 15 Existing lining concrete 15a End face 16 of existing lining concrete End form 17a First hollow pipe 17b Second hollow Pipe 17c Third hollow pipe 18 Multi-stage hollow pipe 19 Vibrator cable 20 Bar-shaped vibrators 21a, 21b, 21c Locking sleeve 22 Covering surface 23 Covering space 24 Concrete placement hole 25 Cord winding device 26 Locking protrusion X Tunnel axial direction (Drilling direction)

Claims (4)

In the tunnel lining concrete placement method of forming lining concrete using a tunnel lining formwork,
A plurality of different outer diameters are provided in the lining space between the outer peripheral surface of the tunnel lining formwork and the lining surface of the inner periphery of the tunnel, which is sandwiched between the end surface of the existing lining concrete and the end formwork. A multi-stage hollow pipe with a smaller outer diameter, which is slidably inserted into a hollow pipe with a smaller outer diameter in order to allow the entire length to expand and contract. The hollow pipe is disposed on the existing lining concrete side and attached in a state of being extended in the axial direction of the tunnel, and a rod-like vibrator is disposed by protruding from the end of the existing lining concrete side of the multistage hollow pipe. The vibrator cable following the rear end portion of the rod-like vibrator is inserted into the multi-stage hollow pipe and extended toward the end form frame, and is disposed through the end form frame. And it can be towed from the outside of the Kitsuma formwork,
While filling and placing concrete in the lining space, pulling the vibrator cable while vibrating the rod-like vibrator, the vibrator cable is left protruding out into the first hollow pipe having the smallest outer diameter. From the locked state, insert the first hollow pipe into the second hollow pipe having the next largest outer diameter until the first hollow pipe is locked to the second hollow pipe,
Further, by pulling the vibrator cable, the second hollow pipe into which the first hollow pipe is inserted is engaged with the third hollow pipe having the next outer diameter, and the second hollow pipe is engaged with the third hollow pipe. Including the step of inserting until it is stopped,
The concrete filled in the lining space is inserted into the hollow pipe with the smaller outer diameter sequentially into the hollow pipe with the larger outer diameter to shrink the multi-stage hollow pipe, and the concrete on the existing lining concrete side A tunnel lining concrete pouring method that compacts from the portion toward the end formwork side.   The vibrator cable is in a state where the rod-like vibrator is linearly protruded from an end portion of the existing lining concrete of the multi-stage hollow pipe, at a base end portion of the first hollow pipe on the second hollow pipe side. The tunnel lining concrete placement method according to claim 1, wherein the tunnel lining concrete is locked to the first hollow pipe.   The tunnel lining concrete placement method according to claim 1 or 2, wherein the lining space is a lining space of a tunnel crown. A tunnel lining concrete placement structure used in the tunnel lining concrete placement method according to any one of claims 1 to 3,
A plurality of different outer diameters are provided in the lining space between the outer peripheral surface of the tunnel lining formwork and the lining surface of the inner periphery of the tunnel, which is sandwiched between the end surface of the existing lining concrete and the end formwork. A multi-stage hollow pipe with a smaller outer diameter, which is slidably inserted into a hollow pipe with a smaller outer diameter in order to allow the entire length to expand and contract. The hollow pipe is disposed on the existing lining concrete side and attached in a state of being extended in the axial direction of the tunnel, and a rod-like vibrator is disposed by protruding from the end of the existing lining concrete side of the multistage hollow pipe. The vibrator cable following the rear end portion of the rod-like vibrator is inserted into the multi-stage hollow pipe and extended toward the end form frame, and is disposed through the end form frame. Available traction from the outside of Kitsuma mold and the tunnel lining concreting structure.

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