JPH03279564A - Stretching method of lining sheet for concrete foam and pulling fixture thereof - Google Patents

Abstract

PURPOSE:To facilitate holding a stretched condition by stretching a lining sheet over the front surface side of a form, placing the peripheral sections of the sheet around each back surface side of the peripheral frame sections of the form, putting each pulling fixture between the peripheral sections of the lining sheet so that the lining sheet is thereby held in tension. CONSTITUTION:A lining sheet 3 which is larger in surface area than a concrete form 2, is spread over the floor surface and the like with its back surface turned upward, so that the form 2 is placed over the back surface of the sheet with its front face turned downward. In the second place, the peripheral sections 3a and 3b of the sheet 3 are bent up so as to be pulled out to the back face sides of the peripheral frame sections of the form 2 in such a way that the frame sections are enclosed by the sheet. Following which, each locking section of the locking pieces 12a and 12b of a pulling fixture 1b is locked to each locking section located at each center of the peripheral sections on the short sides 3b and 3b of the sheet 3 so as to be stretched. In a similar manner, pulling fixtures 1c, 1a and 1a and locked to the peripheral sections on the long sides 3a and 3a of the sheet so as to be stretched. By this constitution, the lining sheet can thereby be easily stretched out so that the sheet can be held in tension in a simple manner.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a method for tensioning a lining sheet in concrete formwork used when pouring concrete structures, and a tensioning tool used in the method. It is something.

[Prior art] Crater-shaped dents (pockets) that occur on the concrete surface impair the surface strength and durability, which are particularly important for concrete structures, and contribute to concrete deterioration. To obtain the structure,
It is important to homogenize the mixing state of concrete and densify the concrete. Therefore, it is necessary to efficiently discharge air bubbles and excess water in the concrete from the formwork to the outside.

As a means of achieving this, in recent years, it has become possible to improve drainage by, for example, lining the surface of the formwork facing the concrete with a sheet made of woven fabric that has water permeability and cement filtering properties. It is being done.

The above-mentioned lining sheet in the conventional formwork for concrete has been stretched over the formwork for concrete as shown in FIGS. 12 and 13, for example.

That is, the lining sheet (200
) on the back side of the concrete formwork (10
0) so that its surface is in contact with the back side of the lining sheet (200), and the left and right front and rear edges of the lining sheet (200) are placed along the sides of the edge frame of the concrete formwork (100). concrete formwork (100) with lining sheet (200)
), and then, while bowing the edge of the lining sheet (100), fix it by driving a tucker table (300) into the edge of the concrete formwork (100). Ta.

[Problem to be solved by the invention] However, as mentioned above, the concrete formwork (100)
In contrast, the edge of the lining sheet (200) is fixed by driving a tacker stable and tensioned. Not only that, but the number of steps required was large, and the installation work was extremely troublesome and time-consuming.

Moreover, even if the edges of the lining sheet are pulled by hand and fixed to the formwork, if the lining sheet, such as a fabric, stretches even slightly due to its material, it will loosen or loosen. As a result, unevenness may occur on the surface of the poured concrete,
There were problems in that the drainage effect of the lining sheet was impaired and pock-like dents were formed on the concrete surface.

In addition, in the case of metal concrete formwork, it is not possible to set the lining sheet by driving a tacker table, so for example, the side edge of the formwork edge and the back side of the lining sheet. By bonding with adhesive,
Attempts have been made to attach a lining sheet, but this adhesive work is troublesome, and there is also a risk that the lining sheet may loosen over time on the surface.

The present invention has been made with the aim of solving the above-mentioned problems.In particular, the lining sheet in concrete formwork can be easily tensioned, and the lining sheet can easily be loosened. The present invention provides a method for tensioning a lining sheet that does not loosen and can maintain a predetermined tension state well, and a tensioning tool used in the method.

[Means to solve the problem]

In order to solve the above-mentioned problems, the present invention provides a method for stretching a lining sheet in a concrete formwork as claimed in claim 1.
It was configured as follows.

That is, a lining sheet having a surface area larger than the surface area of the concrete formwork of the present invention is laminated to the front side of the formwork so that its peripheral edge extends to the back side of the edge frame part, A tension tool having an elastic stretchable part is stretched between the opposing edges of the lining sheet on the back side of the formwork, and the lining sheet is pulled by the elastic force of the elastic stretchable part, thereby creating tension on the surface. It is characterized by being kept in a stretched state.

Furthermore, the tensioning tool used in the above tensioning method is as described in claim 2, and has an elastic stretchable part made of a spring or a rubber band, and has an elastic stretchable part at both ends of the elastic stretchable part. Each of the lining sheets is characterized in that it is provided with one or more locking means for the edge of the lining sheet.

[Function] According to the present invention described above, the lining sheet is stretched around the concrete formwork from the front side to the back side of the edge frame, and on the back side of the formwork, the edge of the opposing lining sheet By locking a tensioning tool to and stretching the elastic stretchable part in a slightly stretched state, for example, the opposing edges in the vertical and horizontal directions are pulled inward by the elastic force of the elastic stretchable part. On the surface side of the formwork, the lining sheet is pulled outward and placed under tension.

In particular, the tensioning tool can easily lock the edge of the lining sheet by means of the locking means provided at both ends of the elastic stretchable part, and the lining sheet is pulled by the elastic force of the elastic stretchable part. Even if the lining sheet were to stretch a little, the elasticity of the elastic expansion/contraction part would be able to cope with this, allowing it to maintain a good tensioned state and not loosening over time. .

[Example] Hereinafter, a method for tensioning a lining sheet in a concrete formwork and a tensioning tool according to the present invention will be described based on drawings showing examples.

The tension tool (la) (la), (lb) C1c) is
As shown in Figure 1, the edges (3a) (3b) of the lining sheet (3) stretched over the surface of the concrete formwork (2)
), that is, it is extended to the back side of the edge frame portion of the formwork (2) and is secured to and spanned by the opposing edges (3a) and (3b).

Each tensioning tool (la) (lb) (lc) is the second
Figure (a).

It has the forms shown in (b) and (c).

That is, the elastic expansion/contraction part (11
) and bifurcated locking pieces (12a) (12b) connected to both ends of this elastic stretchable part (11), and each of the locking pieces (12a) (12b) has a lining sheet at its tip. (3) A hook-shaped locking part (
13) (13) is provided.

The one shown in Fig. 2(a) is a tensioning tool that is secured near both longitudinal ends of the lining sheet (3) and stretched over the opposing long side edges (3a) (3a). (la), one locking piece (12a) (12a) is formed longer than the other locking piece (12b) (12b).

The one shown in Fig. 2(b) is a tensioning tool that is secured at the center in the width direction and stretched over both edges (3b) on the opposite short sides of the lining sheet (3). (lb), and both image retaining pieces (12a) and (12b) are formed to have the same length.

What is shown in FIG. 2(e) is a tensioning tool (lc) that is stretched at the center between both opposing long side edges (Ha) (3a) of the lining sheet (3). , both image retaining pieces (12a) and (12b) are formed to have the same length.

FIG. 3 shows a concrete formwork (2). This formwork for concrete (2) can be formed integrally to a predetermined size, but in the case shown in the figure, a plurality of single formworks (21) in the form of narrow rectangles made of metal such as steel plates are used (in the case of the figure). In this case, three pieces) are connected by a connecting member (4)...

The formwork unit (21) is shown in Fig. 4 (a) (b) (e)
As shown in (d), side frame plates (21b) and (21c) are provided on the four peripheries on the back side of the top plate (21a), and the back side has a concave shape, and the widthwise central part in this concave part A reinforcing plate (21d) extending in the longitudinal direction is provided, and a plurality of reinforcing plates (21e) are provided at required intervals in the longitudinal direction.
Reinforced. The reinforcing plate (21d) is the side frame plate (
21b) and 21c to prevent the tensioner (2b) from coming into contact with the reinforcing plate (21d).

Further, in the side frame plates (21c) (21c) of this formwork unit (21), particularly in the longitudinal direction, there are insertion holes into which one end (4a) of a connector (4) to be described next is inserted. (21f
') are provided.

As shown in FIG. 5, the connector (4) has an L-shaped portion (4b) on one end and a U-shaped portion (4c) that is bent and extended from the L-shaped portion (4b). ).

Then, as shown in Fig. 6, the formwork alone (21) (21
) with the side frame plates (21c) facing each other in the longitudinal direction, connect the - end (4a) of the L-shaped part (4b) of the connector (4) to these side frame plates (21e). ) (21c)
They are connected by fitting the U-shaped portions (4c) into the insertion holes (21f) (21f) and sandwiching the both side frame plates (21c) (21c).

As described above, multiple formwork units (21) (21) (
21) connected to the concrete formwork (2), the lining sheet (3) is attached to the above-mentioned tensioning tools (la) (lb) (lc
) The procedure for tensioning is shown in Figure 7 (a), (b), and (c).
) (d) Explained by (e).

First, as shown in Figure 7(a), formwork for concrete (
Lining sheet (3) having a surface area larger than the surface area of (2)
) on the floor, etc., with the back side facing up. Furthermore, the concrete formwork (
2) Place it with the surface facing down.

Next, as shown in Fig. 7(b), bend the front, rear, left and right edges (3a) (3b) of the lining sheet (3), and Rotate it until the inner sheet (3) wraps around the concrete formwork (2).

Then, as shown in FIG. 7(C), the elastic stretchable part (11) of the tensioning tool (lb) is slightly stretched against its elasticity, and the locking pieces (12a ) (
12b), each locking part (13) (13) is attached to the lining sheet (
3) Short side edge (3b) (3b) Engaging portion provided in the center (examples thereof are shown in FIGS. 9, 10, and 11)
Attach and hang it.

Next, as shown in FIG. 7(d), the tension tool (lc)
With the elastic elastic parts (11) of the lining sheet (1) stretched, the locking parts (13) of the locking pieces (12a) (12b) at both ends are attached to the long side edges (3a) of the lining sheet (1). ) Lock and span the engaging part in the center of (3a) in the same manner as above.

Finally, as shown in Figure 7(e), two tensioning tools (l
a) With each elastic expansion/contraction part (11) of (la) stretched, both end locking pieces (12b) and each locking part (1 of (12b))
3) on the long side edge (3a) of the lining sheet (3) (3a)
) and hang it over the hook. Particularly at this time, the locking part (13) of one locking piece (12a) is made by overlapping both edges (3a) (3b) of the long side and short side as shown in FIG.
It is locked to both edges (3a) and (3b).

In the above manner, as shown in FIG. 7(e) and FIG. It is stretched at the side by the elastic force of the elastic stretchable part (11).

The engaging portions on the front, rear, left, and right edges of the lining sheet (3) may be buttonholes or simple eyelet-shaped engaging holes (31 ), the shape shown in FIGS. 9, 10, and 11 can also be used.

In Fig. 9, a tongue piece (34) is formed on the edge of the lining sheet (3), and an eyelet (32) is fixed to this tongue piece (34). Each locking part (13) of the tension tool (La) (lb) (lc) is inserted into the engagement hole (31a).
) is locked.

Fig. 10 shows the tongue piece (35) extending on the edge of the lining sheet (3) folded back and the end edge of this tongue piece (35) sewn to the lining sheet (3) for engagement. An entry hole (31b) is formed, and a tensioning tool (la) is inserted into this entry hole (31b).
The locking portions (13) of (lb) and (lc) are locked.

Figure 11 shows that the edge of the lining sheet (3) is folded back, the reinforcing plate material (33) is rolled in, and the edge is folded back to the lining sheet (3).
The reinforcing plate material (33) is sewn to the main body part of the reinforcing plate material (33), and an insertion through hole (31c) is formed along the inside of the part where the reinforcing plate material (33) is present. (l
a) The locking portions (13) of (lb) and (lc) are configured to be locked.

In addition, in the above embodiment, the tensioning tools (la) (lb) (
Although the elastic extensible portion (11) of the IC) is made of a spring, the present invention is not limited to this, and the elastic extensible portion (11) may be formed of an extensible body such as a rubber tube or a rubber band. It is possible.

Also, the locking pieces of the tensioning tools (la) (lb') (lc)
12a) (12b) is not limited to a bifurcated shape as shown in the figure, but can also be a book or three or more, for example.
In any case, the shape of the locking part (13) may be a hook shape or any other structure as long as it can be locked to the above-mentioned engaging part.

Further, in the above embodiments, the mold for concrete and cleat (2) is made of metal, but it goes without saying that the mold can be made of wood, for example, in the same manner as described above.

[Effects of the Invention] As explained above, the present invention provides a tension tool having an elastic stretchable portion on the opposite edge of the lining sheet stretched on the concrete formwork on the back side of the concrete formwork. Since the lining sheet is stretched across the inner sheet and both edges are pulled by the elastic force of the elastic stretchable portion to maintain the tensioned state, the following effects can be achieved.

In other words, the lining sheet can be tensioned in the concrete formwork by simply locking the locking pieces at both ends to the edges of the lining sheet while the elastic stretchable part of the tension tool is stretched. , this work can be done easily.

Moreover, since the lining sheet is pulled by the elastic force of the elastic stretchable section, even if the lining sheet stretches a little, the elasticity of the elastic stretchable section can cope with this and maintain good tension. Because it maintains its original state and does not loosen over time, it allows for better drainage during concrete pouring, and prevents pock-like dents from forming on the surface of the poured concrete. , concrete can be placed well.

[Brief explanation of the drawing]

FIG. 1 is a back view showing a state in which the lining sheet is stretched over a concrete formwork using an embodiment of the lining sheet tensioning tool according to the present invention, and FIG. 2(a), ( b),
(c) is a plan view showing the shape of one embodiment of the tensioning tool;
The figure is a back view showing an example of a formwork for concrete formed by connecting formwork units with connectors, FIG. 4(a) is a perspective view of the formwork unit as seen from the front side, and FIG. 4(b) ) is a perspective view of the formwork as seen from the back side, Fig. 4(C) is a side view of the formwork only, Fig. 4(d) is a back view of the formwork only, and Fig. 5 is a view of the above-mentioned connector. A perspective view, FIG. 6 is a partially enlarged perspective view showing a state in which the formworks are connected by a connecting tool, and FIGS. 7(a) and (b)
), (c), (d), and (e) are explanatory diagrams showing the procedure for tensioning the lining sheet onto the concrete formwork using a tension tool, and Figure 8 shows the locked state of the corner part. A partial perspective view showing
FIGS. 9, 10, and 11 are partial perspective views showing examples of the engaging portions of the edge of the lining sheet, FIG. 12, and FIG. 1, respectively.
FIG. 3 is an explanatory diagram showing a conventional example. (Explanation of symbols) (la) (lb) (lc) -- Tension tool (2)...
・・・・・・・・・・・・・・・Concrete (3)・・・
・・・・・・・・・・・・・・・ Lining sheet (3a)
(3b)......Edge (11)...
・・・・・・・・・・・・Elastic stretch part (12a)
(12b)...Locking piece (13)...
・・・・・・・・・・・・・・・Formwork for locking part

Claims (1)

[Claims] 1. A method for installing a lining sheet in a concrete formwork, comprising: pasting a lining sheet having a surface area larger than the surface area of the concrete formwork on the surface side of the formwork. and extending the peripheral edge thereof to the back side of the edge frame part, and extending a tensioning tool having an elastic stretchable part between the opposing edges of the lining sheet on the back side of the formwork, A method for tensioning a lining sheet in a concrete formwork, characterized by maintaining the lining sheet in a tensioned state by tensioning the lining sheet with the elastic force of an elastic stretchable part. 2. A tension tool for tensioning the lining sheet in concrete formwork, which has an elastic stretchable part made of a spring or rubber band, etc., and has edges of the lining sheet at both ends of the elastic stretchable part. 1. A tensioning tool for a lining sheet in a concrete formwork, comprising one or more locking means for the part.