JP3375320B2 - Arch concrete casting method and arch concrete casting center - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for compacting an axial end (gum side) of ready-mixed concrete, for example, the ready-mixed concrete that is placed when lining arch concrete on the inner wall surface of a tunnel, and for placing concrete. It is about Centle.

[0002]

2. Description of the Prior Art Tunnels are usually excavated rocks,
Alternatively, arch concrete is placed on the inside of the primary lining concrete sprayed on the bedrock, or the waterproof sheet stretched over the primary lining concrete, or the primary lining surface by the shield method (hereinafter these are referred to as tunnel inner wall surfaces). ing. 9 and 10 when placing concrete arches
As shown in, a concrete placing form (centre) C is placed inside the tunnel inner wall surface B, and a concrete G is poured from the inlet F of the centle C into the space E between the center C and the tunnel inner wall surface B. Is being injected (placed). in this case,
In order to prevent a gap from being formed between the completed arch concrete and the tunnel inner wall surface B by sufficiently filling the space E with the ready-mixed concrete G, conventionally, as shown in FIG. Then, the fresh concrete G is filled in every corner of the space E.

The arch concrete constructed by the conventional method has the following problems. 1. Hair cracks are unavoidable in arch concrete, which is a reinforced concrete tunnel lining. In particular, the concrete on the gable plate side is more likely to have a poor mixture (more water and less cement) than the concrete in other parts, the strength of the concrete is weaker than other parts, and cracks occur within about 30 cm in the vicinity of the gable plate. Occurrence and peeling and peeling of concrete pieces in that part are likely to occur.
The cause is as follows. As the fresh concrete poured into the space rises from the bottom to the top, the fresh concrete is compacted with a bar-shaped vibrator. In this case, the end plate must be removed in order to insert the vibrator, and the end plate must be compacted by the vibrator before the end plate is attached. However, it is difficult to attach the end plate so that the fresh concrete flowing on the concrete immediately after compaction does not leak from the end side of the placing space. Also, if it is near the top of the pouring space, the concrete pouring work cannot be done because the fresh concrete flows out from the side without the gable plate. For this reason, near the top of the gable side, gable plates are attached before pouring fresh concrete. However, attaching gable plates and pouring ready-mixed concrete poses the following problems.

2. Of the fresh concrete injected from the injection port F (Fig. 9) equipped at the top of the center, poor mix of the concrete (water /
(The one with a large cement ratio) first reaches the gable board, and this is repeated in sequence to form arch concrete on the gable board side, so the concrete on the gable board side tends to be in a poor mix compared to other parts, and the concrete strength is high. It is weaker than the other parts. The arch concrete is formed by moving the centle in the axial direction of the tunnel and placing fresh concrete in the next placing space, so the arch concrete will be spliced on the end plate side, and the splicing part will be the above-mentioned. As described above, it is formed of poorly mixed raw concrete, and its strength is weakened, and cracks are easily generated, and concrete pieces in that portion are easily peeled off.

3. If the gable board is attached and the ready-mixed concrete is sufficiently filled up to the gable board, the injection pressure of the ready-mixed concrete may damage or detach the board and the ready-mixed concrete may flow out to the outside. For this reason, the injection of fresh concrete must be stopped halfway and the space must be filled with fresh concrete to the extent that the gable plate does not break or come off. However, if this is done, the injection pressure will be insufficient and the amount of ready-mixed concrete on the end plate side will be insufficient. In particular, near the top of the gable board, the fresh concrete is only dammed up by the gable board and raised, so the injection pressure is insufficient and the fresh concrete does not completely adhere to the inner wall surface of the tunnel. There may be a gap in When the strength of the end plate is increased in order to solve this problem, the injection pressure of the green concrete becomes too strong, and other parts of the center may be deformed or damaged.
Even when the fresh concrete is filled to the extent that it comes into close contact with the inner wall surface of the tunnel at the beginning of injection, the raw concrete shrinks slightly in volume when it solidifies. A void is generated between the two. In particular, for the above reason, a void is likely to occur near the top end of the end plate.

If the concrete strength in the vicinity of the gable plate is made equal to or higher than that of the other portions, cracks that are likely to occur in the concrete splicing portion and peeling and peeling of concrete pieces in that portion are prevented. For this reason, there have been proposed methods and devices for strengthening the concrete by dehydrating, consolidating and compacting the fresh concrete near the gable plate. The outline of them is as follows.

1. As disclosed in Japanese Unexamined Patent Publication No. 5-156895, a water-permeable cloth or paper sheet is attached only to the end plate, especially to the face plate portion up to about 30 cm which is an easily workable range from the end plate portion. By using a water-permeable form, it is possible to reliably dehydrate the gable part of green concrete, and a concrete splicing method to improve the strength of the gable plate part by using a rich mix (mixing with a small water / cement ratio).

2. As disclosed in Japanese Patent Laid-Open No. 11-247600, the injected fresh concrete is caused to flow out from the wife side of the space, and pressure is applied to the fresh concrete in the space through the leaked fresh concrete to remove the ready concrete on the wife side. A concrete pouring device that pushes back with a lid and applies pressure to improve the filling property of the gable side concrete and also the compressive strength.

3. As disclosed in JP-A-8-21197, a method in which a piston device is installed near the roof plate side of the center and near the top end, and the concrete injected into the space is rocked and compacted to strengthen the concrete of the wife part. .

[0010]

The above-mentioned concrete joining method is disadvantageous in that the color tone of the finished surface of the concrete is different from that of the other portions. In addition, when pouring concrete, it is necessary to attach a water-permeable cloth or a sheet of paper or to extend wrinkles, and it cannot be diverted without washing with water. There is a problem that it is necessary to replace it and it is costly.

Although the concrete placing device of the above-mentioned 2 has a consolidation effect and is desirable, it is not a method of strengthening by reducing the water / cement ratio of the concrete of the end plate part, but only the strengthening of weak concrete. There is a problem that the quality cannot be completely improved.

[0012] In the formwork device for tunnel lining of 3 above, since it is possible to rock and compact the concrete from the shoulder to the top end, which has been difficult in the past, it is possible to strengthen the gable side of arch concrete. There is a problem that the formwork device is expensive and that maintenance is time-consuming.

[0013]

SUMMARY OF THE INVENTION An object of the present invention is to easily and surely perform compaction work not only from the entire arch concrete of a tunnel but also from the top end of the gable side, which is a weak point, to the shoulder. An object of the present invention is to provide a method for compacting arch concrete and a centr for placing concrete which are made possible.

[0014] pouring method of arch concrete according to claim 1 of the present invention, arranged Sentoru 2 inside the tunnel 1
Then, a casting space 3 is formed between them and fixed to the center 2.
Placed end plate 4 in the casting space 3 and place it in the end plate 4
Excess water of fresh concrete within 3
A through hole through which spills such as mortar and fine aggregate can flow out 9
A large number of are formed and fresh concrete is poured into the casting space 3.
Install the excess raw concrete water, laitance, and water.
The effluent, such as mortar and fine aggregate, which have a large content, is discharged through the through hole
More spilled, spillage progressed and ready-mixed concrete
When the coarse aggregate inside reaches the through hole 9, the coarse aggregate, the fine aggregate and the
As if the through hole 9 was clogged with tar and plugged
Then , the vibrator 6 is inserted into the fresh concrete in the casting space 3 from the insertion port 5 formed in the end plate 4, and the fresh concrete is vibrated and compacted.

The method for placing arch concrete according to claim 2 of the present invention is the method for placing arch concrete according to claim 1.
In the placing method, the effluent flowing out from the through hole 9 is converted into a gable plate.
4 is received outside by the receiving body 10 provided outside the center 2.
It is a method of discharging to the department.

According to a third aspect of the present invention, the arch concrete pouring centle has a batten plate 4 fixed to the centle.
An insertion port 5 for inserting the ibrator is formed, and the gable plate of the insertion port 5 is formed.
4, surplus water of ready-mixed concrete in the casting space 3, leitan
Spills such as gas, moist mortar, and fine aggregate
A large number of through holes 9 that can be formed are formed.
The spillage of these spills progresses and coarse aggregate in ready-mixed concrete
When the temperature reaches, the through hole 9 is formed by the coarse aggregate, the fine aggregate and the mortar.
Has a size that causes it to become clogged and plugged
is there.

According to a fourth aspect of the present invention, there is provided an arch concrete placement tool as recited in the third aspect.
The surplus of fresh concrete that flows out of the end plate 4 outside the end plate 5 outside the end plate 4 through the end port 5 and the through hole 9 in the circumferential direction of the center in the center for casting. The receiver 10 is provided to which effluents such as water, leitance, and mortar having a large amount of water flow.

[0018]

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION (Embodiment 1) As an example of a concrete casting centle according to the present invention, a centle 2 is arranged inside an inner wall surface 50 of a tunnel 1 to show an inner wall surface of the tunnel 1. 50 and Centr 2
A pouring space 3 for pouring concrete is formed between the pouring space 3 and the outer peripheral surface of the concrete, and ready-mixed concrete can be poured into the pouring space 3. As shown in FIGS. 3 to 6, the tunnel 1 is sprayed with concrete 12 onto the natural ground 11 to form an inner wall surface 50 of the tunnel.

As shown in FIGS. 1 to 6, at the end portion (the end side) of the casting space 3, a end plate 4 is arranged and closed. As shown in FIG. 4, a large number of insertion openings 5 are opened from the shoulder to the top of the end plate 4. The insertion port 5 is for inserting or withdrawing the rod-shaped vibrator 6. If the insertion ports 5 are provided at intervals of 50 cm to 60 cm,
From the outside of the end plate 4 to the inside of each insertion port 5, a vibrator 6
Can be inserted to vibrate and compact the entire ready-mixed concrete in the casting space 3. The insertion port 5 can also be provided in the entire circumferential direction of the end plate 4. In FIG. 4, a hole is made in the end plate 4, a cylindrical guide 13 is attached to the outside of the hole by welding or other means to form an insertion port 5, and a vibrator 6 can be inserted into the casting space 3 through the guide 13. I am able to do it.

The insertion port 5 can be opened and closed with a lid 8. When inserting the vibrator 6, the lid 8 is opened, and after the vibrator 6 is pulled out, the lid 8 is closed and the fresh concrete in the casting space 3 is inserted. From leaking out. The structure, movement, etc. of the lid 8 are not particularly limited, but as an example, ones shown in FIGS. 7A, 7B and 8 are conceivable.
What is shown in FIGS. 7A and 7B is a slide type lid 8. This is because the plate-shaped lid 8 is slidably inserted vertically into the gap between the end plate 4 and the guide plate 15 attached to its inner surface, and is pulled up by hand to be locked by the locking tool 16 to be held upward. Is held in a state where the insertion port 5 is opened,
The insertion port 5 is closed by releasing the locking by and pushing it down. The lid 8 shown in FIG. 8 is a plug-like member that can be inserted into or withdrawn from the guide 13 of the insertion port 5, so that the insertion port 5 is closed when inserted, and the insertion port 5 is opened when pulled out. There is. Further, the through hole 17 opened in the peripheral wall of the guide 13 and the through hole 19 opened in the insertion cylinder portion 18 of the lid 8 are aligned with each other, and the pin 20 is inserted into both the through holes 17, 19 to carelessly cover the lid 8. It is designed so that it can be prevented from coming off. Further, as shown in FIG. 8, the lid 8 is hung on the guide 13 to prevent the lid 8 from being dropped or lost. This
If you provide a lid that can open and close the outlet,
Close with a lid and insert the concrete into the casting space.
It is possible to prevent leakage from the inlet.

In FIG. 1, a gutter-shaped receiver 10 is provided outside the end plate 4 and below the insertion port 5. The receiving body 10 has the same circular arc shape as the circular arc-shaped end plate 4, is attached to the end plate 4 along the end plate 4, and has its outlet extended to the left and right outside of the lower part of the center 2. With this structure, the effluent of the fresh concrete in the casting space 3 which flows out from the insertion port 5 of the end plate 4 flows into the receiving body 10 and is discharged to the left and right outer sides of the lower part of the center 2. There is. The outlet of the receiving body 10 can also be led out to the outside from another part of the center 2.

(Embodiment 2) A second embodiment of the present invention is shown in FIG. This is one in which an insertion port 5 is provided in the end plate 4, and a large number of through holes 9 are formed in a portion of the end plate 4 below the insertion port 5. Specifically, a mesh is used in the lower part of the gable plate 4, and the mesh of the mesh is used as the through holes 9. The mesh may be made of any material such as metal, resin and wood. Further, other than the mesh, for example, a punching metal obtained by punching a large number of holes in a metal plate, or a resin plate having a large number of through holes may be used. In any case, the size of the through hole 9 is the surplus water of the ready-mixed concrete poured into the casting space 3,
The size is such that latencies, mortar with high water content, fine aggregate, etc. (collectively referred to as effluent) can pass through and flow out of the end plate 4, but coarse aggregate cannot pass through. The shape of the through hole 9 is not limited to the circular shape, but may be another shape. The through holes 9 can be formed in a part or the whole surface of the end plate 4. When using a mesh as the through hole 9,
It is used on all or part of the gable plate 4. In these cases as well, a trough-shaped receiving body 10 is provided below the end plate 4, and the effluent of the fresh concrete in the casting space 3 that flows out from the through hole 9 flows in and is discharged to the outside of the center 2. Is done.

(Use Example 1) A method of lining arch concrete on the inner wall surface of the tunnel 1 by using the concrete pouring centle shown in FIG. 1 will be described below. In this case, the inner wall surface of the tunnel 1 is one in which the excavated rock (earth) is exposed as it is, one in which the primary lining concrete is sprayed on the rock, one in which segments are arranged by the shield construction method, and one in the primary It may be any of those in which a waterproof sheet is stretched on the inside of lining concrete, and may have a structure other than those.

1. As shown in FIGS. 1 and 2, the centle 2 is arranged inside the inner wall surface 50 of the tunnel 1 to form a pouring space 3 (FIG. 2) for pouring concrete between the inner wall surface 50 and the centle 2. . 2. The end plate 4 is arranged on the end side of the setting space 3 and the air fence 30 is arranged above it to close the end side of the setting space 3. In this case, as shown in FIG. 5 and FIG.
And place two air fences 30 on it,
A pusher 33 is arranged on the outside of the air fence 30 as shown in FIGS. 4 and 6 to support the air fence 30 from the outside. As shown in FIG. 6, the pusher 33 has a rod-shaped movable body 35 vertically slidably inserted into a rectangular tubular holding body 34 fixed to the outside of the support body 31, and a screw hole formed in the holding body 34. The movable body 35 can be fixed at an arbitrary position by inserting the locking bolt 36 (FIGS. 4 and 6) into the and pressing its tip against the outer peripheral surface of the movable body 35. In FIG. 4, the pushers 33 are arranged at regular intervals in the circumferential direction of the center 2, but the number of the pushers 33 may be larger or smaller than this, and the arrangement intervals may not be constant. Further, the number of air fences 30 can be set to any desired number. 3. Fresh concrete is poured into the casting space 3 from the inlet of the center 2. The poured fresh concrete is spread and filled in the casting space 3 at the angle of repose. At this time, poorly mixed ready-mixed concrete first reaches the wife side. 4. After opening the lid 8 of the insertion port 5 of the gable plate 4, the insertion port 5
Insert the bar-shaped vibrator 6 into the
The ready-mixed concrete inside is vibrated and compacted. In this case, surplus water of vibrated fresh concrete, leitance,
An effluent such as a mortar with a lot of water flows out of the end plate 4 through the insertion port 5, and the defective concrete on the end plate 4 side is defective.
Unwanted parts are discharged. The rod-shaped vibrator 6 can be of any length, and the insertion depth of the vibrator 6 is also selected arbitrarily. If a long vibrator 6 is used, the insertion depth also becomes long. The longer the insertion depth, the more vibrant the concrete in the interior of the pouring space 3 can be vibrated, and the compaction can be completed in the interior. By the way, the commercially available rod-shaped vibrator 6 has several meters,
If it can be used, it is also possible to specially prepare and use the one having a length of 10 m or more. 5. When the compaction work is completed, the vibrator 6 is pulled out from the insertion port 5, and the insertion port 5 is closed by the lid 8.

(Use Example 2) As shown in FIG. 4, the insertion port 5 is opened in the end plate 4, and the end plate 4 is formed.
A method of lining arch concrete on the inner wall surface of the tunnel by using a center with a mesh underneath will be described below. 1. The centle 2 is arranged inside the inner wall surface 50 of the tunnel 1 to form the casting space 3 between the inner wall surface 50 and the centle 2, and the wife plate 4 is arranged on the wife side of the casting space 3 and above it. An air fence 30 is placed in the space to block the end of the pouring space 3, pouring fresh concrete into the pouring space 3 through the injection port of the center 2 and opening the lid 8 of the insertion port 5 of the end plate 4. The rod-shaped vibrator 6 is inserted into the insertion port 5 and the ready-mixed concrete in the casting space 3 is vibrated and compacted, as in the case of the first use example. 2. In this example of use, out of raw concrete poured into the pouring space 3, effluents such as surplus water, leitance, and mortar with a large amount of water flow out from the through holes (mesh mesh) 9 of the end plate 2 and the end plate 4 side. Defective raw concrete, unnecessary parts are discharged. The effluent flowing out from the through hole 9 is received by the receiving body 10 below the outer side of the end plate 4 and discharged to the outside of the center 2. When the outflow of effluent progresses to some extent, the coarse aggregate in the fresh concrete comes into contact with the through hole 9, and the through hole 9 is clogged with the coarse aggregate, the fine aggregate and the mortar, and becomes a plugged state. . Moreover, the ready-mixed concrete is compacted and reinforced by the vibration of the vibrator 6. 3. When the compaction work is completed, the vibrator 6 is pulled out from the insertion port 5, and the insertion port 5 is closed by the lid 8.

[0027]

Pouring method of arch concrete according to the first aspect of the present invention according to the present invention, since compacted by vibrating the raw concrete in between punching設空by vibrator forme difference from receptacle of end plate following such effects There is. 1. The strength (quality) of concrete near the gable plate is significantly improved. Therefore, even if the center is moved and the arch concrete is continuously placed, the generation of cracks that were likely to occur on the end side of the concrete splicing part is prevented, and the peeling and peeling of concrete at that part is prevented. . 2. Compaction on the end plate side, which has been considered difficult until now, and compaction from the shoulder to the top end, which was rarely done, can be easily performed with the end plate attached, and the arch concrete near the end plate can be used. The strength of the weak point is greatly improved, the generation of cracks that are likely to occur on the end side of the concrete splicing part is prevented, and the peeling and peeling of the concrete in the part are prevented. 3. Since it is vibrated and compacted by the vibrator, the construction is easy, the construction labor hardly increases, and the construction cost does not become particularly high. 4. Even in a reinforced concrete section, the distribution force bars in the front and rear spans are usually not continuous, so construction is possible.

In the method for placing arch concrete according to a second aspect of the present invention, the effluent flowing out from the through hole is removed from the gable plate.
It is received by the receiver installed on the lower side and discharged to the outside of the center.
Therefore, excess water, leitance, and watery moles in the effluent
Tar, etc. are discharged to the outside of the center, and
Work scaffolding does not become dirty and spills deteriorate the work environment.
There is no.

The center for concrete pouring according to claim 3 of the present invention has the following effects. 1. Since the insertion port into which the rod-shaped vibrator can be inserted is provided in the gable plate, the rod-shaped vibrator can be inserted into the fresh concrete in the placing space from the insertion port to vibrate the fresh concrete . Therefore, the ready-mixed concrete on the gable side can be reliably compacted, and the quality of the concrete near the gable plate can be improved. 2. Since the concrete can be compacted by inserting a vibrator into the insertion opening of the gable plate, the construction is easy and requires little labor. 3. Due to the simple construction, the cost of the gable plate is not significantly higher than that of a normal steel gable plate. 4. It can also be applied to assembling and disassembling Baracentre.

In the concrete pouring centr according to claim 3 of the present invention, since a large number of through holes are provided in the gable plate in addition to the insertion port, there are the following effects in addition to the effects of the centr . 1. Excess water, laitance, and mortar with a lot of water in the pouring space, such as mortar and mortar, flow out from the through holes to the outside of the end plate, and the defective concrete on the end plate 4 side and unnecessary parts are discharged. Quality is improved. 2. At the same time as the spillage, the oil of the release agent that dissolves from the center also spills out, reducing the oil streaks on the concrete finish surface near the gable plate, which has occurred in the conventional concrete placing method.

According to the fourth aspect of the present invention, in the concrete pouring center, since the gutter-shaped receiver is provided outside the end plate and below the insertion port and the through hole, the outside of the end plate from the insertion port and the through hole. Effluent such as surplus water of raw concrete, laitance, and mortar with high moisture in the pouring space that flows out to the outside flows into the receiver and is discharged to the outside of the centle, and the work scaffolding inside the tunnel is not contaminated. Does not get worse.

[Brief description of drawings]

FIG. 1 is a schematic front view showing an arch concrete end plate structure of the present invention.

FIG. 2 is a side surface explanatory view of a gable side of the concrete placing space of the present invention.

FIG. 3 is a side view of the end plate portion of the concrete placing space of the present invention.

FIG. 4 is a front explanatory view of the end plate portion of the concrete placing space of the present invention.

FIG. 5 is a side vertical cross-sectional view of the end plate portion of the present invention.

FIG. 6 is a vertical cross-sectional view showing a state in which a vibrator is inserted into the ready-mixed concrete in the concrete placing space from outside the end plate in the present invention.

FIG. 7 (a) is a vertical sectional side view showing an example of the insertion port of the gable plate in the present invention, and FIG. 7 (b) is a front view of the insertion port.

FIG. 8 is a vertical sectional side view showing another example of the insertion port of the end plate according to the present invention.

FIG. 9 is an explanatory diagram showing an arrangement example of a sentle in a tunnel.

FIG. 10 is an explanatory view showing a state of pouring concrete into a concrete placing space.

[Explanation of symbols]

1 tunnel 2 centle 3 Placing space 4 wife plate 5 outlet 6 vibrator 8 lid 9 through holes 10 Recipient

─────────────────────────────────────────────────── ─── Continuation of front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) E21D 11/10

Claims (4)

(57) [Claims] 1. A center (2) is provided inside the tunnel (1).
Place them to form a casting space (3) between them,
Arrange the gable plate (4) fixed to (2) in the casting space (3)
Of the concrete in the pouring space (3) on the end plate (4).
Excess water, leitance, moist mortar, fine aggregate
A large number of through holes (9) through which the discharged effluent can flow out are formed.
Pour fresh concrete into the casting space (3) and
Concrete surplus water, laitance, moist mortar
The effluents such as fine particles and fine aggregate are discharged from the through hole (9).
And the spillage is progressing and the coarse aggregate in the ready-mixed concrete
Reach the through hole (9), coarse aggregate, fine aggregate and mortar
This caused the through hole (9) to become clogged and plugged.
In this way , the vibrator (6) is inserted into the fresh concrete in the casting space (3) from the insertion port (5) formed in the end plate (4) to vibrate and compact the fresh concrete. pouring method of arch concrete. 2. Placing arch concrete according to claim 1.
In the method, the effluent flowing out from the through hole (9) is converted into a gable plate.
It is received by the receiving body (10) provided below the outside of (4).
Archon characterized by being discharged to the outside of the module (2)
How to place cleats. 3. A vibrating plate (4) fixed to the center.
An insertion port (5) for inserting the latator is formed, and the end plate
Excess water of ready-mixed concrete in the pouring space (3) in (4),
Spillage of laitance, moist mortar, fine aggregate
A large number of through holes (9) through which substances can flow out are formed.
In (9), the outflow of effluent from the through hole (9) progressed, and
When the coarse aggregate in the concrete reaches, it becomes coarse aggregate and fine aggregate.
The through hole (9) was clogged with mortar and plugged.
A center for arch concrete pouring, which is characterized by its size . 4. For placing arch concrete according to claim 3.
In the center, outside the end plate (4), below the insertion port (5) and the through hole (9), in the circumferential direction of the center.
The receptacle (10) into which effluents such as surplus water of raw concrete, leitance, and mortar containing a large amount of water flowing out of the gable plate (4) through the insertion port (5) and the through hole (9) flow into
Center for pouring arch concrete.