JPH05133096A - Concrete placing form - Google Patents

Abstract

PURPOSE:To facilitate the work of releasing a form and improve work efficiency by applying a determined synthetic resin film or coating material to the inner surface of a light metal sheathing board, and placing concrete therein followed by solidification and curing. CONSTITUTION:A synthetic resin film 2 of polyethylene, polyester, polypropylene or the like is adhered to the inner surface of a light metal sheathing board 1 through an adhesive 3.Otherwise, a synthetic resin coating material of fluorine, urethane, acryl, polyester, epoxy, vinyl chloride or the like is applied to the inner surface of the light metal sheathing board 1 followed by baking. Concrete is placed in the inner part followed by solidification and curing. Thus, form release after solidification is facilitated to smoothen a finished surface, corrosion of the light metal surface is prevented to increase durability, and the form can be reused.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a concrete pouring mold which enables efficient pouring work when constructing a concrete structure using a light metal formwork at a construction site. It is about the frame.

[0002]

2. Description of the Related Art Conventionally used concrete casting forms are mainly made of wood, plywood, steel (metal foam) or the like. Due to rising labor costs, deterioration of imported plywood quality, and improvement of formwork accuracy, the work area that can be processed by a formwork carpenter per person has become small, so it is important to reduce the weight of formwork materials. I have been asked. Therefore, recently, light metals have been used for the purpose of reducing labor hours, improving work efficiency, and improving working conditions.

Especially, the form panel made of light metal has a specific gravity of steel 1
The aluminum alloy for structural use has a strength that is almost the same as that of ordinary structural steel, and does not cause rust like steel, and can be rolled, extruded, etc. It has excellent workability.

[0004]

As described above, the structural aluminum alloy has the advantageous features, but on the other hand, it has the drawback of being poor in alkali resistance. That is, the main component of cement, which is the main component of concrete, is tricalcium silicate, which reacts with water to release half of the lime component in the form of calcium hydroxide, and the other half is tobermorite-like hydration. It becomes a calcium silicate hydrated product called the product. Since the released calcium hydroxide has a strong alkalinity, it easily reacts with the aluminum of the weir plate in contact with concrete to generate hydrogen, which easily causes corrosion on the surface of the weir plate. As a result, the surface of the concrete becomes rough and the peelability from the concrete when demolding the form from the concrete deteriorates, which causes severe damage to the form and reduces the number of diversions. There is.

At present, various releasing agents are used on the inner surface of the mold in order to improve the releasability from concrete.
The performance required for this release agent is, of course, good releasability, but at the same time, it is easy to handle and helps to improve durability, and the concrete surface can be finished neatly. You must meet the conditions. Therefore, vegetable oils, mineral oils, paraffins, surfactants, etc. are used as stripping agents, but since the surface energy of aluminum is 500 dyne / cm, which is extremely large, it is possible to use concrete cast in a light metal formwork. Since the adhesion of the mold is high, it is not possible to easily remove the mold, and there is the inconvenience of applying a release agent to the inner surface of the mold each time concrete is placed. There are problems such as poor efficiency.

In view of these problems, the present invention uses a weir plate made of light metal in order to reduce the weight of the mold, but the release agent as described above is used on the inner surface of the light metal mold. It is possible to smoothly perform the demolding work of the mold without applying the coating, prevent corrosion of the light metal surface, increase durability, and form a clean concrete finished surface without rough skin. The purpose is to provide a formwork for concrete pouring.

[0007]

In order to achieve the above object, the present invention is characterized in that a synthetic resin film or a synthetic resin coating is adhered or coated on the inner surface of a light metal weir plate. Made of polyethylene resin,
A synthetic resin film such as polyester resin or polypropylene resin is adhered, or a synthetic resin paint such as fluororesin, urethane resin, acrylic resin, polyester resin, epoxy resin, or vinyl chloride is applied to the inner surface of the light metal barrier plate. It is something to paint.

[0008]

Next, the operation state of the present invention will be described. The synthetic resin film adhered to the inner surface of the weir board made of light metal or the synthetic resin paint applied to it will give lubricity to the surface, so it is necessary to remove the mold from the cast concrete. The construction can be done easily and the construction efficiency can be remarkably improved.

[0009]

EXAMPLES Examples of the present invention will be specifically described below. The surface performance of the synthetic resin film or the coated synthetic resin coating adhered to the inner surface of the light metal barrier plate must satisfy the following conditions.

1. The contact surface with concrete should be as smooth as possible. It is desirable that the surface has smoothness in order to easily remove the mold after concrete is poured into the mold and cured and cured.

2. Low surface energy for water. The adhesive force between various substances and concrete is stronger when the surface of the substance is easily wet and the intermolecular attractive force acts on each other. In other words, substances having a large surface energy with respect to water, such as aluminum, iron, and copper, are easily adhered, and substances having a small surface energy with respect to water, such as polyethylene resin, polystyrene resin, polypropylene resin, melamine resin,
Silicone resin or the like is difficult to bond.

3. It must be a material with strong impact resistance. When concrete, which is a mixture of coarse aggregate, fine aggregate, cement, and water, is placed and compacted by a vibrator, the impact of the coarse aggregate is applied to the surface of the formwork. However, it is necessary to have a property capable of sufficiently withstanding this impact.

4. It must be a material with low water absorption. During the hardening and curing period of concrete, the formwork surface is kept in a wet state, and therefore it is necessary that the formwork does not swell or deteriorate in strength during that period.

5. A synthetic resin material with good adhesion to light metals.

As synthetic resin materials satisfying the above conditions, phthalic acid resin, phenol resin, vinyl resin, melamine resin, epoxy resin, polyester resin, polyurethane resin, acrylic resin, silicone resin,
Although there are fluororesins etc., polyethylene resin, polyester resin, polypropylene resin, etc. are used as synthetic resin film, and synthetic resin paint has great weather resistance, chemical resistance, chemical resistance, and abrasion resistance. Fluororesin is the most suitable.

Example 1 A coating material (for example, Silicoat manufactured by Nippon Paint Co., Ltd.) whose main raw material is a silicone polyester resin obtained by modifying an oil-free polyester resin with a silicon intermediate is applied to the inner surface of the dam plate with a roll coater and then baked.

Example 2: Chromate treatment was applied to the surface of an aluminum mold to form a film having strong corrosion resistance, and a fluororesin-based paint (for example, Durana manufactured by Nippon Paint Co., Ltd.) was applied thereon by spray coating. Bake it.

Example 3 A coating containing silicon polyester resin as a main raw material obtained by modifying an oil-free polyester resin with a silicon intermediate (for example, Silicoat manufactured by Nippon Paint Co., Ltd.) is applied to the inner surface of the dam plate by a roll coater, and then baked.

FIG. 1 is a cross-sectional view of a mold made by adhering a synthetic resin film 2 to the surface of a light metal mold 1 via an adhesive layer 3, and FIG. 2 is a surface of the light metal mold 1. FIG. 3 shows a cross-sectional view of the mold frame coated with the synthetic resin paint 2 '.
Using the light metal mold obtained in this way, after the concrete is cast into the mold and solidified and cured, cement does not adhere to the coated surface at all. The demolding work can be easily performed, and it is not necessary to apply a release agent to the inner surface of the mold, and the mold can be reused.

[0020]

The present invention is constructed as described above, and has the following effects. That is, the synthetic resin film adhered to the inner surface of the metal barrier plate is polyethylene resin, polyester resin, polypropylene resin, or the like,
Alternatively, the synthetic resin coating applied to the inner surface of the metal barrier plate is fluororesin, urethane resin, acrylic resin, polyester resin, epoxy resin, vinyl chloride, etc.
Since these synthetic resin materials are rich in lubricity, it is possible to smoothly perform the demolding work of the mold, prevent corrosion of the light metal surface to increase the durability, and to keep the skin clean and clean. It has features such as the ability to form a concrete surface.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a mold in which a synthetic resin film is bonded to the surface of a light metal mold via an adhesive layer.

FIG. 2 is a cross-sectional view of a mold made by coating a synthetic resin paint on the surface of the light metal mold.

[Explanation of symbols]

 1 Light metal form 2 Synthetic resin film 3 Adhesive layer

Front page continuation (72) Inventor Takeshi Yamaguchi 5-chome Mitsuigaoka, Neyagawa-shi, Osaka 1-89-102 (72) Inventor Shuichiro Furuya 3-16 Karigigaoka, Hirakata-shi, Osaka B-8-301

Claims (3)

[Claims] 1. A concrete pouring formwork characterized by being formed by adhering or coating a synthetic resin film or a synthetic resin coating on the inner surface of a light metal barrier plate. 2. A polyethylene resin, a polyester resin,
The concrete pouring formwork according to claim 1, wherein a synthetic resin film such as polypropylene resin is adhered. 3. The concrete pouring formwork according to claim 1, which is coated with a synthetic resin paint such as a fluororesin, a urethane resin, an acrylic resin, a polyester resin, an epoxy resin, or vinyl chloride.