JPH02252860A - Sheeting for concrete forming - Google Patents

Abstract

PURPOSE:To make it unnecessary to use a large pattern-removing force and to prevent the removal of the concrete surface layer by using a sheeting for concrete forming to which a double-woven fabric which allows the passage of water but prevents the passage of concrete is fixed. CONSTITUTION:A double-woven fabric 14 is composed of a front side organization 24 made by crossing each other woofs 24a and warps 24b which consists of a nylon-polyester complex fiber at least in one side, allowing the passage of water but preventing the passage of concrete, and a rear side organization 26 which has woofs 26a consisting of a single synthetic fiber. Then, the fabric 14 is installed to the concrete attaching surface of a plate 12 which has at least one penetrating hole 18, to compose a sheeting for concrete forming. And the excessive water of the concreting is made possible to exhaust to the external space prescribed by the sheeting 10 through the front side organization 24, the clearance 28 between the front side organization 24 and the plate 12, and the ventilating hole 18.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a weir plate forming a part of a formwork for forming concrete.

(Prior Art) Conventionally, a weir plate has been used which has a plate and a fabric attached to cover one side of the plate and which allows water to pass through but prevents concrete from passing through, and the constituent threads of the fabric are The weft and warp yarns each consist of a single synthetic fiber.

(Problem to be Solved by the Invention) According to the weir board, a portion of surplus water seeping out from the consort that is poured in the space defined by the plurality of weir boards and in contact with the fabric of each weir board is removed during curing. is discharged through the fabric. Draining the excess water promotes solidification of the surface layer of the concrete molding, which enables early demolding.

Further, fine particles including cement particles, fine aggregate powder, etc. in the concrete carried by surplus water stay in a layer between the concrete and the fabric, and later harden to form the concrete molded material. Constitutes the surface layer. The surface layer formed by solidifying the fine particles has higher density and hardness than other parts of the concrete molding, and maintains the quality of the concrete molding for a long time.
Contributes to promoting longevity, etc.

However, although the weir plate including the fabric provides the above-mentioned advantages, it requires a large demolding force to separate the fabric attached to the concrete molding during demolding. Also, demolding f2. , li The surface layer of the concrete molded article sometimes peeled off while remaining attached to the fabric.

An object of the present invention is to provide a weir plate for forming concrete that includes a fabric defining the contact surface with concrete, and which can be removed from the mold with less force than conventional weir plates.

(Means for Solving the Problems, Actions and Effects of the Invention) The weir plate for concrete forming according to the present invention includes a plate,
a double weave fabric attached to the plate and covering one side of the plate, the double weave fabric having a face texture that allows the passage of water but prevents the passage of concrete, and a back texture that opposes the one side of the plate; woven fabric, at least one of the weft and warp of the surface structure of the fabric is made of nylon-polyester composite fiber.

According to the present invention, a portion of the surplus water of the concrete cast in the space defined by the weir plate is absorbed by the surface structure of the fabric of the weir plate and the surface structure retained by the back structure of the fabric. The liquid is discharged to the outside of the space sequentially through the gap between the plate and, if a through hole is provided in the plate, further through the through hole.

By the way, the nylon fibers defining the surface of the nylon-polyester composite fibers constituting the weft or warp of the surface texture and the polyester fibers integral therewith can be stretched in a humid environment, and the elongation of the nylon m fibers is The ratio is higher than the polyester fiber. For this reason,
The weft yarns or the warp yarns are elongated relative to the concrete by coming into contact with the excess water.

At this time, the deformation of the fabric in contact with the concrete due to the elongation of the weft or warp does not impair the flatness of the molding surface of the concrete due to the elongation limiting effect of the nylon fibers by the polyester fibers. It can be kept to a certain extent.

When a portion of the excess water is completely discharged as the cement in the concrete sets, the weft or warp yarns shrink depending on the degree of dryness of the fabric. This shrinkage causes parts of the weft or warp to separate from the concrete forming surface. Therefore, a part of the fabric is peeled off from the concrete forming surface on the demolding surface, which reduces the force of peeling the weir plate from the concrete forming surface during demolding,
Furthermore, by reducing the peeling force of the weir plate, it is possible to prevent the surface layer of the concrete molded product from peeling off during demolding.

The constituent yarns of the backing structure of the fabric may be monofilament yarns or multifilament yarns, but in the case of monofilament yarns, due to the high elasticity of the monofilament yarns, the lateral pressure of the concrete between the surface structure and the plate is reduced. It is possible to secure a flow path for the surplus water that can be maintained under the action of , and to improve the discharge of the surplus water.

The woven fabric is a woven fabric consisting only of the 11η notation structure, that is, -
71 fabrics. In this case, since it is difficult to secure a passage for the surplus water between the fabric described in Section 111 and the plate, at least one through hole is provided in the plate, and the chain hole is used for the excess water that has passed through the fabric. As a drainage passage for

Preferably, the weft and warp of the fabric each have a flat portion. Fabrics that have flat portions have a smaller surface area than fabrics that do not have flat portions. Therefore, the contact area between the fabric and the concrete is small, and the force required to peel the weir plate from the concrete for demolding can be made smaller.

(Example) Referring to FIGS. 1 to 4, a weir plate 10 forming a part of a concrete molding form is shown.

The weir plate 10 is a plate 1 having an overall rectangular planar shape.
2, and a fabric 14ζ attached to the plate 12 and covering one side (surface) 12a of the plate, the fabric 14 forming the surface of the weir plate 10, that is, the contact surface with concrete.

The plate 12 is provided with at least one through hole 18 that opens on its front surface 12a and its back surface (the other surface) 12b, as necessary. It is desirable that the surface 12a of the plate is smooth. The illustrated plate 12 is comprised of plywood and an acrylic resin layer applied to one side thereof, the acrylic resin layer providing the plate 12 with a smooth surface 12a. The plate 12 can be formed of, for example, a metal plate, a plastic plate, etc. other than the illustrated example.

The fabric 14 has a peripheral edge 14a that is folded back from the front surface 12a of the plate to the back surface 12b. The peripheral edge 14a is connected to the back surface 1 of the plate by a number of stables or tackers 16.
2b, whereby the fabric 14 is secured to the plate 12.
is attached to. The fabric 14 can also be attached to the plate 12 by gluing the peripheral edge 14a to the back side 12b of the plate. This installation work can be carried out, for example, at a construction site where the weir plate 10 is used.

A plurality of crosspieces 20 are arranged on the back surface 12b of the plate, each extending in the horizontal and vertical directions of the plate. Each crosspiece is fixed to the plate 12 with a plurality of nails 22 that are driven into the plate 12 from the surface of the fabric 14 and pass through the plate 12 four times. When a plurality of weir plates 10 are arranged so that the fabric 14 defines the contact surface with the poured concrete in order to define a concrete placement space, the crosspiece 20 on the back side of each weir plate 10 is made of a suitable member. (not shown).

The fabric 14 shown in FIG. 5, FIG. 6, and FIG. 7 is a weft double weave fabric, and has a front set &1f 124 consisting of a plurality of wefts 24a and a plurality of warps 24b intersecting with each other,
A plurality of other weft yarns 2 that intersect with the warp yarns 24b of the surface texture
6a. Surfaces II & 24 have a texture density that allows the passage of water but prevents the passage of concrete. On the other hand,
The backing 26 contacts the surface 12a of the plate and maintains a number of gaps 28 between the surface and the facing 24.

Excess water seeping out of concrete cast in a space defined by a plurality of weir plates 10, for example, a space forming a wall of a building, is absorbed by the surface structure 24 of the fabric 14, the space 28, and the plate 12.
It passes through the through holes 1B in sequence and is discharged to the outside of the space. Each space 28 defines a flow path for excess water that has passed through the table &124. The backing structure 26 functions as a spacer for holding the space 28 and also serves to guide a portion of the surplus water from the surface assembly &124 to the through hole 18 of the plate 12.

If the plate 12 is not provided with the through-holes 18, the excess water that has passed through the surface structure 24 will flow downward through the spaces 28 and from between the weir plates 10 and between the lowermost weir plate 10 and the ground. , respectively, flow out of the space in which the wall body is formed.

The surface 1i24, which prevents the passage of concrete, that is, a mixture of cement, aggregate, and water, has its weft threads 24a.
The warp threads 24b act as a filter to prevent passage of a large number of fine particles such as cement particles and fine bone powder having a particle size larger than the space defined by the warp threads 24b. Therefore, the large number of fine particles are held in a layer between the weir plate 10 and the concrete in contact with it. These layers of fine particles solidify and form the surface layer of the concrete molding. The surface layer defining the concrete molding surface has a higher hardness and higher density than the inner depth of the concrete molding.

By the way, as shown in FIG. 8, the weft yarn 24a of the surface texture
At least one of the warp yarns 24b, preferably both as in the illustrated example, is made of nylon-polyester composite fiber. The nylon-polyester composite fiber is a fiber that is integrally spun using polyester fiber A and nylon fiber B as a core and a sheath, respectively. In contrast, the weft threads 26a of the backing structure are made of a single synthetic fiber.

The constituent yarns of the front weave 24 and back weave 26 of the fabric may be either monofilament yarn or multifilament yarn. However, in the case of an example in which the plate 12 does not have the d through-hole 18, it is desirable that the weft yarn 26a of the front set &I 26 is composed of the monofilament yarn. Monofilament yarns have greater elasticity compared to multifilament yarns, and for this reason, under the action of the lateral pressure of the concrete between the plate 12 and the surface structure 24, a channel for the total excess water (nη of T capacity) is maintained ( This is because it is easy to secure the space 28). In addition, it does not matter whether the multifilament yarn is twisted or untwisted.

The nylon-polyester composite YA fiber has the property of elongating in a humid environment. For this reason, the weft thread 24a
Alternatively, when the warp yarns 24b come into contact with the excess water, they elongate relative to the concrete. The elongation rate of nylon fiber B is greater than that of polyester fiber A, and polyester fiber A resists and limits the elongation of nylon 11a fiber B. Due to the effect of restricting the elongation of the nylon fibers B by the polyester fibers A, the uneven deformation of the surface of the fabric 14 in contact with the concrete caused by the elongation of each of the weft yarns 24a and the warp yarns 24b affects the flatness of the molding surface of the concrete. I can't suppress it to the extent that it doesn't damage it.

As the concrete hardens and the discharge amount of the surplus water decreases, each weft thread 24a and each warp thread 24
b shrinks, and a part of them peels off from the molded surface of the concrete. Thereby, the weir plate 10 can be peeled off with less force during demolding. The forming surface of the concrete is not damaged by the separation of part of the weft threads 24a and warp threads 24b.

Furthermore, due to the effect of restricting the elongation of the nylon fibers B by the polyester fibers A, the amount of elongation of the weft yarns 24a and warp yarns 24b is smaller than when the weft yarns and warp yarns are composed of only the nylon fibers.

Referring to FIG. 6, which shows an example of the fabric, the front fabric &124 has a hand-woven texture. The plurality of weft threads 26a of the back weave constitute a weave point every seven with the plurality of warp threads 24b of the front weave 24, and each weft thread 26a is located directly below each weft thread 24a of the front weft Jii24. The situation during this time will be clear from FIG. 7, which shows the overlapping of both weft threads 24a and 26a in each row a to g.

Next, we will discuss the peeling force of both weir plates from concrete during demolding when using the weir plate of the present invention having double weave fabric A described later and the weir plate having double weave fabric B described later. The measured values are shown in the table below.

Fabric A: Weft yarn of the surface structure - Twisted nylon-polyester composite fiber yarn (100 denier multifilament yarn) Warp yarn of the surface structure - Twisted nylon-polynisdel composite yarn (multifilament yarn of 1000 denier) Back structure Weft - Untwisted polyester yarn (960 denier multifilament yarn) Texture of surface texture - Density of plain weave surface texture - (30 (weft) and 36 (
Warp) ) /i12 Fabric B: Weft of surface texture - twisted polypropylene yarn (1000 denier multifilament yarn) Warp of surface texture - twisted polyester yarn (multifilament yarn of 1000 denier) Weft of back texture - None Twisted polyester yarn (960 denier multifilament yarn) Weave structure of surface structure - Texture density of plain weave surface structure - (30 threads (weft) and 36 threads (weft)
Warp))/1n2 (Unit = g/m2) Each weir board used in the measurement had a similar structure to the weir board described in Figs. Each has a length dimension. The above measured values were obtained from concrete cast in a space defined by a weir plate and three plates arranged vertically and assembled to form a rectangular shape when viewed from above, and after a curing period of 48 hours. It is the magnitude of the peeling force of the weir plate, and the area of the contact surface of the weir plate with the concrete is 0.81 ra' (0.9 m
．． The magnitude of the peeling force shown in Table 0, which is A pantograph jack and a soil pressure gauge are placed in sequence between them.
The jack is operated so that the distance between the two horizontal bars increases, and the force that one horizontal bar receives at this time is the maximum value among the values recorded by the pen recorder. The values listed in the columns for the first, second, and third uses of the above coating are the values obtained using unused weir plates, and the values that are obtained when using the weir plates that have been used once. Values obtained after cleaning the material to wash away powder, etc. and using it again; and
This value was obtained by cleaning the weir plate that had been used twice and then using it again.

From this result, it can be seen that the peeling force that should be exerted on the weir plate having Fabric A having a nylon-polyester composite fiber thread as a constituent thread of the face texture is the same as that of the weir plate having Fabric B having a single synthetic fiber thread as a constituent thread of the face texture. It can be seen that it is significantly reduced compared to the board.

As shown in FIG. 7, the weft threads 24a and the warp threads 24b of the facing fabric 24 may have flat portions 30 and 32, respectively.

The flat portions 30 and 32 are formed by, for example, placing the fabric 14 between a heating roller and a non-heating roller that are pressed toward each other, so that the front texture 24 and the back texture 26 are in contact with the heating roller and the non-heating roller, respectively. This can be obtained by calendaring, which is carried out side by side.

For example, the fabric A is calendered by setting the surface temperature of a heating roller having a length of 2.2 m to 100° C. and setting the set pressing load to 20 t.

As a result of the calendering, a portion of the bays of the weft 24a and warp yarns 24b defining the surface of the fabric are plastically deformed into oblate shapes, and these oblate portions provide flat portions 30 and 32. As is clear from the aspect of each row B-yg in FIG. 7, the cross-sectional shape of the weft yarns 24a and warp yarns 24b of the surface texture z4 in contact with the heating roller changes from a substantially circular shape to a substantially semicylindrical shape. The weft threads 26a of the back weave 26 and the warp threads 24b of the face weave 24 and the weft threads of the face weave 2 in contact with the non-heating roller are also 8,
The cross-sectional shape changes from approximately circular to approximately elliptical and is plastically deformed.

The surface area of the fabric 14 with flat portions 30 and 32, ie the area in contact with the concrete, is smaller than before calendering. For this reason, weir plate 10 is used for demolding.
It is possible to further reduce the peeling force that should be applied to the surface.

Furthermore, if at least one of the weft yarns 24a and the warp yarns 24b of the surface structure is made of monofilament yarn, the magnitude of the peeling force is further reduced compared to the case where both the weft yarns and the warp yarns are made of multifilament yarns. be able to. This is because monofilament yarn does not have the fuzz that occurs when some filaments are cut, which is seen in multifilament yarn, and therefore it is necessary to apply force to the weir plate to break the adhesion of the fuzz and concrete. That's because there isn't.

The fabric 14 is a warp double weave instead of the horizontal double weave shown in the figure.
Rope, warp and width double weave, or lining 26
In other words, it can be a single-ply fabric consisting only of the same weave structure as the surface structure 24. However, the above-
If a heavy fabric is used, the plate 12 shall have through holes 18. This is because a space 28 cannot be obtained between the double weave fabric and the plate as in the case of using the double weave fabric. Further, the front weave 24 can be a satin weave or a twill weave instead of the plain weave shown. Furthermore, the warp threads 24b of the front weave, which cooperate with the weft threads 26a of the back weave to form weave points, can be arbitrarily selected.

[Brief explanation of drawings]

, FIGS. 1 and 2 are partially cutaway front and rear views of a weir plate according to the present invention, and FIGS. 3 and 4 are views taken along lines 3-3 and 4-4 in FIG. Fig. 5 is a partial cross-sectional view of the weir plate conceptually showing the texture of the fabric, Fig. 6 is a partially enlarged exploded perspective view of the fabric, and Fig. 7 is a cross-sectional view and longitudinal cross-sectional view of the weir plate obtained by FIG. 6 is a partially enlarged view seen from the direction of arrow A shown in FIG. 6, and FIG. 8 is a cross-sectional view of the nylon-polyester composite fiber. 10: Weir plate, 12 Nibrate, 14: Fabric, 24.24a, 24b: Face weave, weft and warp of face weave, 26.26a: Back weave and its weft, 30.32:
flat part.

Claims (5)

[Claims] (1) A plate, a double-woven fabric attached to the plate and covering one side of the plate, which allows water to pass through but prevents concrete from passing through, and a back side facing the one side of the plate. 1. A weir board for concrete forming, comprising a double-woven fabric having a texture, wherein at least one of the weft and warp of the surface texture of the fabric is made of nylon-polyester composite fiber. (2) The weir plate for concrete forming according to claim (1), wherein the constituent threads of the backing structure are monofilament threads. (3) a plate, and a single layer of fabric attached to the plate and covering one side of the plate that allows the passage of water but prevents the passage of concrete, the fabric having at least one of its weft and warp yarns made of nylon. Weir plate for concrete forming made of polyester composite fiber. (4) The weir plate for concrete forming according to claim (1) or (3), wherein the weft thread and the warp thread each have a flat portion. (5) The weir plate for concrete forming according to claim (1) or (3), wherein the plate has at least one through hole.