JP2964557B2 - Tunnel lining concrete casting formwork - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention is suitably used for concrete casting as a centrifugal formwork for tunnel construction, for removing water generated from concrete from a concrete casting surface, The present invention relates to a lining concrete casting formwork for a tunnel capable of easily exchanging a surface sheet for facilitating the work of removing the formwork from the concrete casting surface after the concrete is solidified over a large area.

[Conventional technology]

BACKGROUND ART Conventionally, in casting concrete, a formwork made of wooden plywood or an iron frame has been used, and concrete has been cast in contact with these formwork. However, when concrete is poured and solidified using these forms, traces of water bubbles generated by the moisture mixed with the concrete remain on the concrete surface in contact with the forms, causing fine irregularities, It is not possible to obtain a concrete-casting surface, and these irregularities cause a reduction in strength.

For this reason, recently, for the purpose of positively removing the water present on the concrete casting surface from the concrete casting surface, for example, as disclosed in Japanese Patent Application Laid-Open No. 61-151366, a cloth sheet or It has been proposed to apply a water-absorbent sheet such as a non-woven fabric, and to use a mold that is configured to absorb excess moisture and air bubbles into these cloth sheets and the non-woven fabric. Thereby, it is possible to remove water and air bubbles from the concrete casting surface and to cast concrete neatly.

[Problems to be solved by the invention]

Here, in the tunnel construction, when concrete is laid on the excavated surface of the tunnel, an aggregate of a formwork (indicated by reference numeral a in the figure) of about 30 × 150 cm called a centur as shown in FIG. Concrete is poured while moving the centrifugal form along the tunnel axial direction, and the concrete is laid on the entire excavated surface.

Formwork a that constitutes such a tunnel construction tunnel
When the water-absorbing sheet as described above is disposed on the surface on the side where concrete is cast, the water-absorbing capacity of the water-absorbing sheet decreases as the centrifugal form is moved and the concrete casting is repeated, or the sheet is damaged. A smooth concrete casting surface cannot be obtained, and it is necessary to replace the water-absorbing sheet on each mold surface. However, as shown in FIG. 8, the centrifugal formwork is formed by fixing a number of formworks of about 30 × 150 cm side by side, for example, formed in an arch shape. Replacing all the conductive sheets requires a great deal of labor, and it is difficult to perform such a work in terms of work efficiency.

The present invention has been made in view of the above circumstances, and can easily replace a surface sheet such as a water-absorbent sheet or an easily peelable sheet over a large area, and can be used as a tunnel as a movable form such as a centre form. It is an object of the present invention to provide a lining concrete casting formwork suitable for forming a continuous large-area concrete wall such as lining concrete.

[Means for solving the problem]

In order to achieve the above object, the present invention provides a tunnel lining in which a surface sheet such as an easily peelable sheet or a water-absorbing sheet is disposed on one surface of a mold body, and concrete is cast on the surface sheet. In concrete casting formwork,
The cassette body is removably fixed on the formwork body, and one or more topsheets on which one or more sheets are detachably stacked are detachably attached to the cassette body, thereby deteriorating the function of the topsheet. Provided is a formwork for placing lining concrete in a tunnel, which is formed so as to be replaceable in the event that the work is performed.

Here, examples of the top sheet include a woven fabric, a nonwoven fabric, a knitted fabric, a material in which a water-absorbing polymer substance is dispersed therein, and a water-absorbing sheet in which a plastic film having a large number of fine through holes is laminated thereon. Can be mentioned.

When two or more of the above surface sheets are laminated and used so as to be peelable from each other, they can be laminated using an acrylic ester-based, natural or synthetic rubber-based pressure-sensitive adhesive, or the like.

[Action]

The concrete casting form of the present invention is used to form a continuous large-area wall or the like, such as tunnel lining concrete, particularly as a movable form such as a centre form, and covers a large area. As a result, the topsheet can be easily replaced, so that the concrete can be cast neatly over a large area.

In this case, if the function of the topsheet deteriorates when concrete is repeatedly cast as a movable formwork such as a centrifugal formwork, it is easy to remove the topsheet from the cassette body and attach a new topsheet to the cassette body. You can replace the topsheet. At this time, when a plurality of topsheets are laminated so that they can be peeled off from each other, replacement can be performed a plurality of times simply by peeling off the topmost topsheet, and after all the sheets are used, a plurality of topsheets can be placed on the cassette body You only have to reattach the seat. If the cassette body is detachably fixed to the form body, the cassette body can be removed from the form body and the top sheet can be easily replaced.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

〔Example〕

First Embodiment FIG. 1 shows a concrete casting formwork according to an embodiment of the present invention. This formwork 1 includes a formwork body 2 and a concrete casting side of the formwork body 2. And a top sheet 4 detachably mounted on the top of the cassette body 3. The top sheet 4 extends along opposite sides of the cassette body 3 a. Hook-shaped projection 3 with its tip facing inward
It is housed between b and 3b.

Here, as shown in FIG. 2, the topsheet 4 is made of a polyethylene film or an ethylene-vinyl acetate copolymer (EVA) film in which a large number of fine through holes (not shown) are formed on the nonwoven fabric 5. 100-20M) is an absorbent sheet having a two-layer structure in which a plastic film 6 having excellent releasability (such as 100-20M) is laminated.
It is housed in the cassette body 3.

The cassette body 3 is not particularly limited, but is preferably detachably fixed to the mold body 2. In this case, as a method of detachably fixing the cassette body 3 to the mold body 2, for example, FIGS.
As shown in (C), the form body 2 and the cassette body 3 are overlapped with the holding members 7, 7 having a U-shaped cross section and sandwiched therebetween.
A method of driving wedges 8, 8 between the form body 2 and the cassette body 3 to firmly fix the cassette body 3 on the form body 2 (FIG. A). Insert the formwork body 2 and cassette body 3 in a state of being overlapped between 7,
Method of fixing with springs 9, 9 (Fig. B), form body 2 and cassette body 3 are overlapped, magnets 10, 10, 10, 10 are arranged on both front and back surfaces along both ends, and the magnetic force is applied. A method of clamping and fixing the mold body 2 and the cassette body 3 (FIG. C) can be exemplified.

When the above-mentioned form 1 is configured as a movable form such as a centrifugal form and is used to form a continuous large-area concrete wall or the like, as shown in FIGS. 6 (A) to 6 (C). ,
5 (A) to 5 (C) show the cassette body 3 on the concrete casting side surface of the form body 2 in which a plurality of small frames 2a, 2b, 2c are juxtaposed on a movable support 11. The movable mold 1 according to the present embodiment is detachably fixed by the above method or the like, and concrete 12 is cast on the surface sheet 4 of the mold 1 (FIG. A). In this case, the moisture generated from the cast concrete 12 is absorbed into the nonwoven fabric 5 through the through holes formed in the plastic film 6 of the topsheet 4, and flows through the nonwoven fabric 5 and is discharged to the outside. Therefore, concrete can be cast neatly without leaving traces of water bubbles and fine irregularities due to the presence of moisture on the concrete surface.
In addition, when the cast concrete 12 is cured and cured, the surface of the cast concrete 12 can be kept in an appropriate wet state by the moisture remaining in the nonwoven fabric 5,
Good wet curing can be performed. 13 and 1 in the figure
Reference numerals 4 and 14 denote a horizontal rod and a vertical rod constituting the support 11, respectively.

Next, after the cast concrete 12 has solidified, the form 1 is peeled from the cast concrete 12 (FIG. B). In this case, the cast concrete 12 is cast in contact with the plastic film 6 constituting the topsheet 4, and since the plastic film 6 is excellent in peelability as described above, it does not damage the surface of the cast concrete 12. , Easily formwork 1
Can be peeled from the cast concrete 12.

Next, the form 1 is moved together with the support 11, and a second concrete 12 'continuous with the cast concrete 12 is cast in the same manner as described above (FIG. C). In this case, however, the topsheet is damaged. If the water absorption capacity is reduced due to clogging or the like, the topsheet 4 is removed from the cassette body 3, a new topsheet is stored in the cassette body 3, and the second concrete is placed on the new topsheet. Cast in.
When the topsheet deteriorates in this way, the topsheet can be easily replaced, and concrete can be poured while the topsheet always keeps a good function. In addition, in the formwork 1 of the present embodiment, the cassette body 3
Is detachably fixed to the form body 2, so that when the top sheet is replaced, the top sheet can be more easily replaced by removing the top sheet from the form body 2.

Thereafter, the same operation is repeated to form a continuous large-area concrete wall such as a lining concrete for the tunnel. In this case, the surface sheet 4 is always maintained in a good condition by the replacement of the surface sheet. , And concrete can be repeatedly cast, so that a beautiful concrete wall can be reliably formed.

Second Embodiment FIG. 3 shows a concrete casting formwork according to another embodiment of the present invention. This formwork 15 is made of a nonwoven fabric on a water-impermeable plastic film 16 shown in FIG. Two or more (four in the figure) top sheets 17 formed by laminating two sheets are stacked in a releasable manner and housed in the cassette body 3. The top sheet 17 has a plastic film 16 inside and a nonwoven fabric 2 inside. They are sequentially superposed outward and housed in the cassette body 3. The other configuration is the same as that of the mold 1 of the first embodiment, and the description thereof is omitted.

When this formwork 15 is configured as a movable formwork such as a centrifugal formwork and is used to form a continuous large-area concrete wall or the like, the movable formwork is constructed in the same manner as in the first embodiment. Then, concrete is cast on the surface sheet of the formwork 15. In this case, the moisture generated on the surface of the cast concrete is absorbed into the nonwoven fabric 2 constituting the uppermost surface sheet 17,
It flows through the nonwoven fabric 2 and is discharged to the outside. Therefore, concrete can be cast neatly without leaving traces of water bubbles and fine irregularities due to the presence of moisture on the surface. In addition, as in the case of the mold 1 of the first embodiment (hereinafter simply referred to as the mold 1), the moisture remaining in the nonwoven fabric 2 causes
Good wet curing can be performed. At the time of the above-mentioned water discharge, since the uppermost nonwoven fabric and the second and subsequent nonwoven fabrics are blocked by the water-impermeable plastic film 16, moisture from concrete flows into the second and subsequent nonwoven fabrics. Never.

Next, form the concrete from the cast concrete in the same manner as the form 1 above.
15 is peeled off and the mold 15 is moved to cast the second concrete. In this case, in the mold 15 of the present embodiment, the surface sheet constituting the concrete casting surface is damaged or clogged. If the water absorption capacity of the topsheet is reduced due to the above, the topmost topsheet 17a is removed from the cassette body 3 as shown in FIG. 7, and the second topsheet is placed on the second topsheet. Pour concrete. in this way,
According to the formwork 15 of this embodiment, the topsheet can be easily replaced simply by removing the topmost topsheet.
Further, when the formwork 15 is peeled from the cast concrete and moved, the uppermost surface sheet can be separated from the cassette body 3 and left on the surface of the cast concrete 12 as a curing sheet.

Thereafter, the movement of the formwork and the concrete placement are repeated to form a continuous large-area concrete wall. In this case, when the top sheet runs out, a plurality of top sheets can be reattached to the cassette body 3 and the casting operation can be continued. In this case, the work of attaching the top sheet can be easily performed by removing the cassette body 3 from the mold body 2.

Therefore, according to the formwork 15 of the present embodiment, the deteriorated surface sheet can be easily replaced with a new one, and a movable formwork can be constructed, and concrete can be cast neatly over a large area. Can be.

The present invention is not limited to the above embodiment, and the material and structure of the surface sheet and the cassette body, the method of fixing the cassette body to the mold body, and the like may be variously changed without departing from the gist of the present invention. You can do it.

〔The invention's effect〕

As described above, according to the concrete casting formwork of the present invention, a surface sheet such as a water-absorbent sheet or an easily peelable sheet can be easily replaced over a large area, and as a movable formwork. It is suitably used to form a continuous large-area concrete wall or the like, such as lining concrete for a tunnel, and is capable of casting concrete neatly over a large area.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a concrete casting mold according to one embodiment of the present invention, FIG. 2 is a partially enlarged sectional view showing a surface sheet constituting the same mold, and FIG. 3 is another embodiment. FIG. 4 is a cross-sectional view showing the concrete casting formwork, FIG. 4 is a partially enlarged cross-sectional view showing a top sheet constituting the same formwork, and FIG.
6 (A) to 6 (C) are sectional views showing a method of fixing the cassette body according to the present invention to the formwork body, and FIGS. FIG. 7 is a cross-sectional view for sequentially explaining the steps of concrete pouring used, FIG. 7 is a cross-sectional view showing one step of concrete pouring using the concrete pouring formwork according to the other embodiment, and FIG. It is a perspective view which shows the sentre formwork used when casting lining concrete in construction. 1,15 …… Concrete formwork, 2 …… Form form body, 3
…… Cassette body, 4,17 …… Surface sheet, 12,12 ′ …… Concreting concrete

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A 60-188743 (JP, U) JP-A 57-198245 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) E04G 9/10 101 E21D 11/10

Claims (1)

(57) [Claims] 1. A lining concrete casting formwork for a tunnel in which a surface sheet such as an easily peelable sheet or a water-absorbing sheet is disposed on one surface of a formwork body, and concrete is cast on the surface sheet. In the above, the cassette body is detachably fixed on the formwork body, and one or two or more topsheets are detachably attached to the cassette body so that they can be peeled off from each other. A mold for lining concrete in a tunnel, characterized in that the mold is formed so that it can be replaced when it has deteriorated.