JP2616878B2 - Method for producing permanent formwork, formwork used therefor, and foam sheet - 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 producing a permanent mold, and a mold and a foam sheet used for the method.

[0002]

2. Description of the Related Art In general, when manufacturing a thin permanent mold having a U-shaped cross section, a mold in which an uneven plastic film is attached to the inner surface of an inner mold is formed, and the mold is formed in the mold. Concrete has been cast, and after the concrete has hardened, it is released from the mold to produce a formwork having countless irregularities on the inner surface.

[0003]

However, in order to make the above-mentioned permanent mold into a thin-walled mold, the distance between the outer mold and the inner mold has been narrowed. For this reason, there has been a problem that it is difficult to fill the mold with concrete and it takes time to manufacture. Further, there is also a problem that a molded product has jumpers and the like, and the molded state of the surface is very poor. The present invention has been made in view of such a problem, and an object of the present invention is to provide a method of manufacturing a permanent mold capable of easily manufacturing a permanent mold and preventing the occurrence of jumpers and the like, and a mold used therefor. And a foam sheet.

[0004]

The gist of the method for manufacturing a permanent form according to the present invention for achieving the above object is to adhere a foamed sheet having an innumerable foamed portion filled with a foaming agent to the inner surface. Concrete is poured into the formed formwork, and the foaming agent is foamed with an aqueous solution in the poured concrete to expand the foamed portion to form countless irregularities. After the concrete is cured, the concrete is removed from the mold. Wherein the foaming agent is at least one of aluminum powder, sodium hydrogen carbonate, phosphorus pentoxide, and hydrogen fluoride, and the gist of the mold used in the method for producing a permanent mold is innumerable foamed parts. Is attached to the inner surface of the mold body, the foamed portion is filled with a foaming agent that reacts with the liquid and foams, and the surface is provided with a water supply hole. , The foaming agent is aluminum powder, At least one of sodium hydrogen oxyoxide, phosphorus pentoxide, and hydrogen fluoride, and the gist of the foam sheet used in the method for producing a permanent mold is that a myriad of foam parts react with a liquid to foam. Is filled with a blowing agent
In the water supply hole was provided on the surface of the foaming part,
The blowing agent is aluminum powder, sodium hydrogen carbonate,
It is at least one of phosphorus pentoxide and hydrogen fluoride.

[0005]

Before the concrete is cast, the foam sheet adhered to the inner surface of the mold is attached to the inner surface of the mold as a normal smooth sheet because the foaming agent is not foamed. When the concrete is poured, the foaming agent foams by the aqueous solution in the concrete and expands the foamed portion. Then, when the concrete is cured and then released from the mold, a large number of irregularities are formed on the inner surface of the permanent mold by the innumerable expanded foam portions. In addition, since the foam sheet adhered to the inner surface of the form is a normal smooth sheet before the concrete is cast, the concrete can be easily filled into the form and the occurrence of junkers can be prevented. .

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the method for manufacturing a permanent form according to the present invention will be described below in detail with reference to the drawings. FIG. 1 is a sectional view of a mold used in the method of manufacturing a permanent mold according to the present invention.
Is a plan view of the foam sheet, and FIG. 3 is a sectional view of the same. A mold 1 for manufacturing a permanent mold includes an inner mold 1a and an outer mold 1b.
A foam sheet 2 is adhered to the inner surface of the inner mold frame 1a with an adhesive or a double-sided tape.

The foamed sheet 2 is formed by laminating a flat sheet 2a and an inflatable sheet 2b having countless inflatable foamed portions 3, and the foamed portion 3 contains aluminum foamed in response to an alkaline aqueous solution. A foaming agent 4 such as a powder is filled. The foaming portion 3 is provided with a water supply hole 3a that does not leak the foaming agent 4 but allows an aqueous solution to pass through. The aluminum powder reacts and foams with the alkaline aqueous solution from the water supply hole 3a.

Therefore, the foamed sheet 2 is a sheet having a substantially smooth surface before the aluminum powder is foamed. In addition to the aluminum powder, the above foaming agent 4 is sodium hydrogen carbonate, phosphorus pentoxide, which reacts with water to foam,
Other foaming agents can be used as long as they use hydrogen fluoride or the like, and are not limited to these, and are foaming agents that foam in response to a liquid.

Next, a method of manufacturing a U-shaped thin permanent mold using the mold 1 will be described. First, as shown in FIG. 4, a U-shaped mold 1 including an inner mold 1 a and an outer mold 1 b having a foam sheet 2 adhered to the inner surface with an adhesive or a double-sided tape is prepared. When the foamed portion 3 is not foamed, as shown in (1) of FIG. 3, the surface becomes almost smooth. Therefore, even if the foamed sheet 3 is attached to the inner mold 1a, the foamed sheet 2 is different from the ordinary mold 1 in any way. There is no change. Therefore, even if the distance between the inner mold frame 1a and the outer mold frame 1b is reduced, concrete can be easily poured.

Next, as shown in FIG. 5, concrete 5 is poured into the above-mentioned formwork 1 and, after a lapse of a predetermined time after the casting, an alkaline aqueous solution in the concrete 5 is supplied from the water supply hole 3a to the foamed portion. The aluminum powder is infiltrated into the inside of the foam sheet 3 to form irregularities 6 on the surface of the foam sheet 2.

Next, when the concrete 5 is cured and then released from the mold, as shown in FIG. 6, a permanent mold 7 having an inner surface provided with irregularities 6 can be manufactured. Further, since the foam sheet 2 is attached to the inner mold 1a, it can be peeled off from the inner surface of the concrete 5 together with the inner mold 1a at the time of demolding.

Although the method of manufacturing the permanent mold 7 has been described using the U-shaped mold 1, the present invention is not limited to the U-shape, and the manufacturing method is not limited to the U-shape. Can be manufactured, and a PC plate for an outer wall can also be manufactured by the above method.

FIG. 7 shows the results of an experiment in which concrete was poured into a permanent form produced by the above method, and the adhesion strength between the permanent form and the concrete was confirmed with the lapse of days. According to this, the permanent form provided with irregularities of the present invention is:
It was found that the adhesion strength was 1.5 times larger than that of the permanent mold having no irregularities.

[0014]

The foamed sheet adhered to the inner surface of the formwork is a substantially smooth sheet before the concrete is cast, but when the concrete is cast into the formwork, the aqueous solution in the concrete causes the foamed portion to be in the foamed portion. Since the foaming agent foams and expands the foamed portion, it is possible to easily cast concrete into the formwork, easily manufacture a permanent formwork, and prevent occurrence of junkers and the like.

Before the concrete is cast, the foam sheet adhered to the inner surface of the mold can be adhered to the inner surface of the mold in the same manner as a normal smooth sheet because the foaming agent is not foamed. For example, when manufacturing a U-shaped thin-walled permanent mold, it is possible to ensure a sufficient space between the inner mold and the outer mold.

When concrete is poured into the form, the foamed portion of the foam sheet is expanded by the aqueous solution in the concrete, so that irregularities can be easily formed on the inner surface of the permanent form.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a mold to which a foam sheet having an expanded foam portion is adhered.

FIG. 2 is a plan view of a foam sheet.

FIG. 3A is a cross-sectional view of a foamed sheet in which a foamed portion is not foamed, and FIG. 3B is a cross-sectional view of a foamed sheet in which a foamed portion is expanded.

FIG. 4 is a cross-sectional view of a mold to which a foam sheet before a foam portion expands is attached.

FIG. 5 is a cross-sectional view of a form in which a foamed portion is expanded by casting concrete.

FIG. 6 is a cross-sectional view of the removed permanent mold.

FIG. 7 is a graph showing the bond strength between a permanent form and concrete cast therein.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Formwork 2 Foam sheet 3 Foam part 4 Foaming agent 5 Concrete 6 Irregularity 7 Permanent formwork

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code Agency reference number FI Technical display location // B29K 105: 04 (72) Inventor Kiyohiko Furutajima 1-7-1 Kyobashi, Chuo-ku, Tokyo Toda Construction Co., Ltd. (72) Inventor Shigemi Mochizuki 1-7-1 Kyobashi, Chuo-ku, Tokyo Toda Construction Co., Ltd. (72) Inventor Yu Tokunaga 1-7-1 Kyobashi, Chuo-ku, Tokyo Toda Construction Co., Ltd. (72 Inventor Kiyoshi Kurabayashi 1-7-1 Kyobashi, Chuo-ku, Tokyo Toda Construction Co., Ltd.

Claims (6)

(57) [Claims] 1. Concrete is poured into a formwork in which a foam sheet having countless foamed portions filled with a foaming agent is adhered to an inner surface, and the foaming agent is foamed by an aqueous solution in the cast concrete. A method for producing a permanent form, wherein the foamed portion is expanded to form innumerable irregularities, and the concrete is released after hardening. 2. The foaming agent is aluminum powder, carbonated water.
Sodium fluoride, phosphorus pentoxide, hydrogen fluoride
2. The permanent according to claim 1, wherein the number is one.
Manufacturing method of formwork. 3. A foamed sheet provided with a myriad of foamed parts is a mold.
The foam is adhered to the inner surface of the main body, and the foamed part reacts with the liquid therein.
It is filled with a foaming agent that foams in response to the
Is used in the method of manufacturing permanent forms.
Formwork to use. 4. The foaming agent is aluminum powder, carbonated water.
Sodium fluoride, phosphorus pentoxide, hydrogen fluoride
4. The permanent according to claim 3, wherein the number is one.
Formwork used in the method of manufacturing the formwork. 5. An innumerable foaming part reacts with a liquid and emits.
A foaming agent to be foamed is filled, and a water supply hole is provided on the surface of the foamed portion.
Is used in the method of manufacturing permanent forms.
Foam sheet to use. 6. The foaming agent is aluminum powder, carbonated water.
Sodium fluoride, phosphorus pentoxide, hydrogen fluoride
6. The permanent according to claim 5, wherein the number is one.
A foam sheet used in the method of manufacturing a mold.