JP2001089218A - Ariticial lightweight concrete for curtain wall and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To manufacture light weight concrete for curtain wall having a long plasterable in the time and having excellent plastering property. SOLUTION: This light weight concrete is manufactured by incorporating cement, water, partially or completely dried light weight aggregate, a water reducing agent and at least one kind of an organic agent optionally selected from cellulose-based compounds and polyvinyl alcohol and controlling its spcific gravity to <=1.7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lightweight concrete for a curtain wall and a method for producing the same.

[0002]

2. Description of the Related Art Conventionally, as a lightweight concrete, Japanese Patent Application No.
No. -348381. This is one in which the lightweight concrete includes a lightweight aggregate partially or entirely dried and a water reducing material excellent in dispersibility with respect to the lightweight aggregate.

In order to manufacture a curtain wall or the like using such lightweight concrete, lightweight concrete is cast in a formwork. At this time, while the lightweight concrete keeps its softness, the coarse aggregate rises by buoyancy, and the upper part of the coarse aggregate protrudes from the surface of the lightweight concrete. Even if you try to finish the surface in such a state and push coarse aggregate into lightweight concrete,
Coarse aggregates emerge on the surface of the lightweight concrete.

[0004] For this reason, conventionally, lightweight concrete hardens to some extent and has a hardness appropriate for finishing, that is, a state in which coarse aggregate is held in lightweight concrete even if the coarse aggregate is pushed into the concrete. I waited until it was done, and then I tried to do the ironing by hand (plastering).

[0005]

However, the time required for the lightweight concrete to reach the appropriate hardness for finishing depends on the mixing conditions of the lightweight concrete and the casting environment. Also, the time during which the lightweight concrete has a hardness suitable for finishing is limited, and if the finishing is delayed, the lightweight concrete becomes too hard, and it is difficult to obtain a clean finished surface by manual surface finishing. In other words, forcibly finishing in this state will cause cracks on the surface of the lightweight concrete.

As described above, in the case where a curtain wall is manufactured from lightweight concrete using a lightweight aggregate in a dry state, it has been desired to improve the finishing workability.

The present invention has been made in view of such circumstances, and even when the concrete is in a soft state, the lightweight aggregate does not rise, and the finish time is long, and the surface finish is improved. An object of the present invention is to provide an excellent lightweight concrete for curtain walls and a method for producing the same.

[0008]

The inventor of the present invention has conducted intensive studies to obtain a lightweight concrete for a curtain wall having a long finishable time and good finish, which could not be obtained conventionally, and as a result, a specific concrete has been obtained. It has been found that all of the above conventional problems can be solved by a simple means of adding an organic agent, and the present invention has been completed.

That is, the means of the present invention for solving the above-mentioned problems are as follows. According to the first aspect of the present invention, a lightweight concrete for a curtain wall is arbitrarily selected from cement, water, a partially or entirely dried lightweight aggregate, a water reducing agent, a cellulosic compound and polyvinyl alcohol. It is characterized by containing at least one organic agent.

Here, examples of the cellulosic compound include methylcellulose, hydroxypropylmethylcellulose, hydroxyethylmethylcellulose, hydroxyethylcellulose, carboxymethylcellulose and the like. These cellulosic compounds act to increase the water retention of the mortar and improve workability and adhesiveness.

[0011] As the polyvinyl alcohol,
Fully saponified polyvinyl alcohol, partially saponified polyvinyl alcohol, intermediate saponified polyvinyl alcohol and the like can be mentioned. These polyvinyl alcohols serve to improve the adhesion of the mortar.

In the present invention, the lightweight concrete for a curtain wall contains at least one of the above-mentioned organic agents, and may contain two or more organic agents.

Further, in the lightweight concrete for a curtain wall according to claim 2 of the present invention, the water reducing agent is a polycarboxylic acid-based water reducing agent source water agent, or has a dispersibility similar to or higher than that of the polycarboxylic acid-based water reducing agent. Claim 1.
3. Lightweight concrete for curtain walls according to item 1.

Further, in the lightweight concrete for a curtain wall according to a third aspect of the present invention, the lightweight aggregate is in a completely dry state or a state of not more than half the water absorption of the lightweight aggregate. 3. Lightweight concrete for curtain walls according to item 1.

The lightweight concrete for a curtain wall according to claim 4 of the present invention has a water cement ratio of 35%.
The lightweight concrete for a curtain wall according to any one of claims 1, 2, and 3 described above. If the water cement ratio is less than 35%, the workability of the kneaded concrete will be poor.

In the method for producing a lightweight concrete for a curtain wall according to the fifth aspect of the present invention, the composition is adjusted so that the specific gravity at the time of kneading becomes 1.7 or less. A method for manufacturing a lightweight concrete for a curtain wall, comprising manufacturing the lightweight concrete for a curtain wall according to claim 3 or 4. That is, lightweight concrete having a specific gravity of 1.7 or more can be manufactured without using a dry lightweight aggregate, and does not have the above-described problems.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Curtain walls conventionally manufactured using lightweight concrete are difficult to finish as described above, and plastered surfaces cannot be made as clean surfaces. The face was avoided. However, according to the present invention, by mixing a specific organic agent into lightweight concrete for a curtain wall, a surface plaster finish equal to or higher than that in the case of using conventional concrete that does not use a dry lightweight aggregate is imparted, and it is easy to use. The present invention can provide a lightweight concrete curtain wall having a very smooth finished surface.

The type of cement used for the lightweight concrete for a curtain wall of the present invention is not particularly limited, and can be variously selected depending on the purpose. For example, ordinary cement, early-strength cement, blast furnace cement, low heat cement, and the like can be used.

The type of lightweight aggregate used for the lightweight concrete for a curtain wall of the present invention is not particularly limited for both coarse aggregate and fine aggregate, and various types can be selected according to the purpose. For example, expanded aggregates and expanded aggregates can be used in combination, and specifically, expanded aggregates of expanded shale or expanded clay as coarse aggregates, or those baked using fly ash or the like as a main raw material As a fine aggregate, glass or porcelain raw material, foamed fly ash, expanded shale, expanded clay can be used.

In the lightweight concrete for a curtain wall according to the present invention, if the concrete is kept at a specific gravity of 1.7 or less,
In addition to the lightweight aggregate, ordinary coarse aggregate and fine aggregate that are not lightweight aggregates can be mixed. As the ordinary coarse aggregate and fine aggregate, natural or artificial materials can be used alone or in combination. In this case, gravel, crushed stone,
River sand, crushed sand and stone powder can be used as natural fine aggregate. Further, as the artificial coarse aggregate, a concrete glass, a crushed product of a ceramic product, and as an artificial fine aggregate, a concrete glass, a crushed ceramic, or a foamed crushed ceramic can be used.

The water reducing agent used in the lightweight concrete for a curtain wall of the present invention may be a polycarboxylic acid-based water reducing agent or a dispersing agent having a dispersibility equal to or higher than that of the polycarboxylic acid-based water reducing agent. There is no.

The organic agent used in the lightweight concrete for curtain walls of the present invention is mainly composed of methylcellulose, hydroxypropylmethylcellulose, hydroxyethylmethylcellulose, hydroxyethylcellulose, carboxymethylcellulose, etc., to enhance the water retention of the mortar, to improve workability and adhesiveness. Polyvinyl alcohol (PVA) used for the purpose of improving the adhesiveness of mortar, such as cellulosic compounds used for the purpose of improving mortar, and fully saponified polyvinyl alcohol, partially saponified polyvinyl alcohol, etc. ), At least one of
Use more than kind. Specific products include, for example, Hi-Metrose and Shin-Etsu Poval (trade names, manufactured by Shin-Etsu Chemical Co., Ltd.); ) Kurarepovar and the like.

The amount of the organic agent used in the lightweight concrete for curtain walls of the present invention varies depending on the preparation, but is usually 0.5% to 6.5% of the cement weight, preferably less than 5% of the cement weight. . When the content is 0.5% or less, the effect is not exhibited. When the content is 6.5% or more, the viscosity of the concrete becomes too high, and the workability is reduced.
There is a possibility that the fire resistance performance of the curtain wall, which is a product, is reduced.

The compounding ratio of the lightweight concrete for a curtain wall of the present invention can be the same as that of the conventional one.
The water-cement ratio of the lightweight concrete of the present invention is 29 to
It can be manufactured if the content is 59%, but in the present invention, the content is 35% or more in order to improve workability.

The lightweight concrete for a curtain wall according to the present invention can be put in the same manner as a conventional lightweight concrete by charging a material into a mixer, kneading the mixture, and performing main kneading. As another method, the mortar can be kneaded first, then coarse aggregate can be added thereto, and then the main mortar can be kneaded and poured.

Curing of the lightweight concrete for a curtain wall of the present invention can be natural curing or steam curing in the same manner as curing of conventional lightweight concrete.

[0027]

Embodiments of the present invention will be described below. The following test kneads light weight concrete for curtain walls with a predetermined composition, measures its physical properties (slump value, air volume, temperature, specific gravity, etc.).
It was poured into a formwork of × 1.0m × 0.2m, and the possible finishing time of the surface and workability of plastering were examined.

Example 1 A lightweight concrete of Comparative Example 1 and a lightweight concrete of Example 1 were prepared according to the mixing ratios shown in Table 1 below. In Table 1, cement is Sumitomo Osaka Cement's early-strength cement, fine aggregate is Nippon Mesalite Industry Co., Ltd., trade name lightweight fine aggregate mesalite, coarse aggregate is Nippon Mesalight Industry Co., Ltd., trade name light coarse bone The material is mesalite, and the water reducing agent is a polycarboxylic acid-based water reducing agent, and is a product name of SP-8HE manufactured by NMB Corporation. The organic agent is hi90SH-30000 (trade name, manufactured by Shin-Etsu Chemical Co., Ltd.) containing hydroxypropyl methylcellulose as a main component.

[0029]

[Table 1]

In accordance with the above mixing ratio, each material was put into a twin-screw mixer and kneaded, and the mixed water, a water-reducing agent and an organic agent were charged and the main kneading was carried out. Of lightweight concrete was prepared. The physical properties of the obtained lightweight concrete of Comparative Example 1 and the lightweight concrete of the present example 10 minutes after placing in fresh concrete were measured. Table 2 shows the results. The slump did not change until 35 minutes after the casting.

[0031]

[Table 2]

With the concrete of Comparative Example 1, plastering could be started 50 minutes after the casting, but 60 minutes after the casting.
It became difficult to work. For the concrete of Example 1, plastering could be started from 30 minutes after casting, and work was easy up to 80 minutes after casting.

Example 2 A lightweight concrete of Comparative Example 2 and a lightweight concrete of Example 2 were prepared according to the mixing ratios shown in Table 3 below. In Table 3, cement is Sumitomo Osaka Cement's early-strength cement, fine aggregate is Crystal Clay Co., trade name lightweight fine aggregate G light, coarse aggregate is Nippon Mesalight Industry Co., Ltd. product name light coarse bone The material is Super Mesalite, and the water reducing agent is a polycarboxylic acid-based water reducing agent, trade name Mighty 2000WHZ manufactured by Kao Corporation. The organic agent is MH10005P2 (trade name, manufactured by Clariant Polymer Co., Ltd.) containing methyl cellulose as a main component.

[0034]

[Table 3]

In accordance with the above mixing ratio, each material was put into a twin-screw mixer and kneaded. Then, the mixed water, a water reducing agent and an organic agent were charged and the main kneading was carried out. Of lightweight concrete was prepared. The physical properties of the obtained lightweight concrete of Comparative Example 2 and the lightweight concrete of Example 2 were measured 10 minutes after placing in fresh concrete. Table 4 shows the results. The slump did not change until 35 minutes after the casting.

[0036]

[Table 4]

The concrete of Comparative Example 2 could start plastering 50 minutes after casting, but after 60 minutes from casting,
It became difficult to work. For the concrete of Example 2, plastering could be started from 30 minutes after casting, and work was easy up to 80 minutes after casting.

Further, the ready-mixed concrete was poured into a prescribed formwork to obtain a test specimen having a size of 10 × 10 × 40 cm. Was higher. Table 5 shows the results.

[0039]

[Table 5]

Example 3 A lightweight concrete of Comparative Example 3 and a lightweight concrete of Example 3 were prepared according to the mixing ratios shown in Table 6 below. In Table 6, cement is Sumitomo Osaka Cement's early-strength cement, fine aggregate is Crystal Clay, trade name lightweight fine aggregate G light, coarse aggregate is Taiyo Cement Co., trade name light coarse bone The material is Asano Superlite, and the water reducing agent is a polycarboxylic acid-based water reducing agent manufactured by NOF CORPORATION, trade name: Sudox WRW-150S. SEB-04T (trade name, manufactured by Shin-Etsu Chemical Co., Ltd.) containing hydroxyethyl methyl cellulose as a main component as an organic agent
And PA-18S (trade name, manufactured by Shin-Etsu Chemical Co., Ltd.) mainly containing partially saponified polyvinyl alcohol. The values of the added amounts of the organic agents shown in Table 6 are the total amounts of the two types.

[0041]

[Table 6]

In accordance with the above mixing ratio, each material was put into a twin-screw mixer and kneaded, and then the mixed water, a water reducing agent and an organic agent were charged and the main kneading was carried out. Lightweight concrete was prepared. The physical properties of the obtained lightweight concrete of Comparative Example 3 and the lightweight concrete of Example 3 were measured 10 minutes after placing in ready-mixed concrete. Table 7 shows the results. The slump did not change until 40 minutes after the casting.

[0043]

[Table 7]

The concrete of Comparative Example 3 was able to start plastering 40 minutes after casting, but around 60 minutes after casting,
It was too hard to work. For the concrete of Example 3, plastering could be started 30 minutes after casting, and work was easy up to 110 minutes after casting.

Example 4 A lightweight concrete of Comparative Example 4 and a lightweight concrete of Example 4 were prepared according to the mixing ratios shown in Table 8 below. In Table 8, the cement is ordinary cement manufactured by Sumitomo Osaka Cement Co., Ltd., the fine aggregate is Crystal Clay Co., Ltd., the product name is lightweight fine aggregate G-lite, the coarse aggregate is Nippon Mesalite Industry Co., Ltd., the product name is lightweight coarse aggregate. Mesalite, a water reducing agent is a polycarboxylic acid-based water reducing agent, manufactured by NOF CORPORATION, trade name: Sudox WRW-150S. The organic agent is 90EMP-15000 (trade name, manufactured by Matsumoto Yushi-Seiyaku Co., Ltd.) containing hydroxypropyl methylcellulose as a main component.

[0046]

[Table 8]

In accordance with the above mixing ratio, each material was put into a twin-screw mixer and kneaded, and then the mixed water, a water reducing agent and an organic agent were charged and the main kneading was carried out. Lightweight concrete was prepared. The physical properties of the obtained lightweight concrete of Comparative Example 4 and the lightweight concrete of Example 4 were measured 10 minutes after placing in ready-mixed concrete. Table 9 shows the results. The slump did not change until 25 minutes after the casting.

[0048]

[Table 9]

For the concrete of Comparative Example 4, plastering could be started 30 minutes after casting, but 40 minutes after casting.
It became difficult to work. For the concrete of Example 4, plastering could be started 30 minutes after casting, and work was easy up to 60 minutes after casting. Furthermore, the concrete of Example 4 still maintained sufficient softness to facilitate the work even when the work was completed.

Example 5 A lightweight concrete of Comparative Example 5 and a lightweight concrete of Example 5 were prepared according to the mixing ratios shown in Table 10 below. In Table 10, cement is blast furnace cement B type manufactured by Sumitomo Osaka Cement Co., Ltd., fine aggregate is manufactured by Nippon Mesalite Industry Co., Ltd., trade name lightweight fine aggregate mesalite,
The coarse aggregate is Mesalite, a lightweight lightweight aggregate manufactured by Nippon Mesalite Industry Co., Ltd. The water reducing agent is a polycarboxylic acid-based water reducing agent, SP-8HE, manufactured by NMB Corporation. The organic agent is UF-170 (trade name, manufactured by Unitika Ltd.) containing a completely saponified polyvinyl alcohol as a main component.

[0051]

[Table 10]

In accordance with the above mixing ratio, each material was put into a twin-screw mixer and kneaded. Then, the mixed water, a water reducing agent and an organic agent were charged and the main kneading was carried out. Of lightweight concrete was prepared. The physical properties of the obtained lightweight concrete of Comparative Example 5 and the lightweight concrete of Example 5 were measured 10 minutes after placing in fresh concrete. Table 11 shows the results. The slump did not change until 35 minutes after the casting.

[0053]

[Table 11]

With the concrete of Comparative Example 5, plastering could be started 40 minutes after casting, but 60 minutes after casting,
It became difficult to work. For the concrete of Example 5, plastering could be started 30 minutes after casting, and the work was easy until 80 minutes after casting.

Example 6 A lightweight concrete of Comparative Example 6 and a lightweight concrete of Example 6 were prepared according to the mixing ratios shown in Table 12 below. In Table 12, cement is ordinary cement manufactured by Sumitomo Osaka Cement Co., Ltd., fine aggregate is naturally produced river sand, coarse aggregate is manufactured by Taiyo Cement Co., Ltd., trade name light weight coarse aggregate Asano Super Light, water reducing agent Is a polycarboxylic acid-based water reducing agent manufactured by Kao Corporation, trade name Mighty 200
0TH. The organic agent was a partially saponified polyvinyl alcohol as a main component, manufactured by Shin-Etsu Chemical Co., Ltd., trade name PA-05
S.

[0056]

[Table 12]

In accordance with the above mixing ratio, each material was put into a twin-screw mixer and kneaded, and then the mixed water, a water reducing agent and an organic agent were charged and the main kneading was carried out. Of lightweight concrete was prepared. Physical properties of the obtained lightweight concrete of Comparative Example 6 and the lightweight concrete of Example 6 were measured 10 minutes after placing in ready-mixed concrete. Table 13 shows the results. The slump did not change until 45 minutes after the casting.

[0058]

[Table 13]

With the concrete of Comparative Example 6, plastering could be started 50 minutes after the casting, but 60 minutes after the casting.
It became difficult to work. For the concrete of Example 6, plastering could be started 30 minutes after casting, and work was easy up to 80 minutes after casting.

Further, after the above-mentioned amphibious concrete was poured into the formwork, steam curing was performed with changing the pre-installation time. However, both of the obtained concrete members had no cracks or the like and had a 28-day strength. There was no change.

Example 7 Lightweight concrete of Comparative Example 7 and lightweight concrete of Example 7 were prepared according to the mixing ratios shown in Table 14 below. In Table 14, the cement is low-heat cement manufactured by Sumitomo Osaka Cement Co., Ltd., the fine aggregate is manufactured by Nippon Mesalite Industry Co., Ltd., the trade name is lightweight fine aggregate mesalite, the coarse aggregate is manufactured by Nippon Mesalight Industry Co., Ltd., the trade name is lightweight coarse aggregate. Mesalite, a water reducing agent is a polycarboxylic acid-based water reducing agent, trade name SP-8HE, manufactured by NMB Corporation. The organic agent is UFA170 (trade name, manufactured by Unitika Ltd.) containing polyvinyl alcohol as the main component.

[0062]

[Table 14]

According to the above mixing ratio, each material was put into a twin-screw mixer and kneaded, and then the mixed water, a water reducing agent and an organic agent were charged and the main kneading was carried out. Of lightweight concrete was prepared. The physical properties of the obtained lightweight concrete of Comparative Example 7 and the lightweight concrete of Example 7 were measured 10 minutes after placing in ready-mixed concrete. Table 15 shows the results. The slump did not change until 35 minutes after the casting.

[0064]

[Table 15]

With the concrete of Comparative Example 7, plastering could be started 60 minutes after casting, but around 80 minutes after casting,
It was hard to work. For the concrete of Example 7, plastering can be started 40 minutes after casting, and
Work was easy until 00 minutes later.

Further, the light-weight concrete for a curtain wall according to the present example is tiled and laid out with 3 m × 3
Concrete members obtained by casting in a m × 0.2 m formwork and performing steam curing did not have any cracks, and the tiles had no abnormality at all.

Example 8 A lightweight concrete of Comparative Example 8 and a lightweight concrete of Example 8 were prepared in accordance with the mixing ratios shown in Table 16 below. In Table 16, the cement is Sumitomo Osaka Cement Co., Ltd., a high-strength cement, the lightweight fine aggregate is Ube Industries, Co., Ltd., new U-lite, the lightweight coarse aggregate is Nippon Mesalite Industry Co., Ltd., and the product name is Super Mesalite. Yes, the water reducing agent is a polycarboxylic acid-based water reducing agent, manufactured by NOF CORPORATION, trade name Sudox DJS. Organic agent is manufactured by Clariant Polymer Co., Ltd.
The product name is MH10005P2.

[0068]

[Table 16]

In accordance with the above mixing ratio, each material was put into a twin-screw mixer to perform kneading, and the mixed water, a water reducing agent and an organic agent were charged to perform main kneading. Of lightweight concrete was prepared. Physical properties of the obtained lightweight concrete of Comparative Example 8 and the lightweight concrete of Example 8 were measured 10 minutes after placing in fresh concrete. Table 17 shows the results. The slump did not change until 20 minutes after the casting.

[0070]

[Table 17]

The concrete of Comparative Example 8 was able to start plastering after 10 minutes from the casting, but became hard enough not to work after about 30 minutes from the casting. For the concrete of Example 8, plastering can be started immediately after casting, and
Work was easy until a minute later.

Further, the shape of the concrete member obtained by casting the lightweight concrete for a curtain wall according to Example 8 on a mold frame coated with an oily release agent and a mold frame coated with an aqueous release agent, respectively, is as follows. There was no difference due to the difference in the release agent, and the shape was faithful to the shape of the mold.

[0073]

As described above, the lightweight concrete for a curtain wall according to the present invention can finish plastering quickly after casting and can perform plastering finishing for a longer time than the conventional lightweight concrete. In addition, workability and surface finish will be good,
The finished state of the surface can be improved.

The lightweight concrete for a curtain wall according to the present invention can be quickly steam-cured since the finishing is completed early from the casting, so that the time required for the entire production of the curtain wall can be reduced and the labor can be reduced. By reducing the cost, the cost can be reduced.

Further, in the lightweight concrete of the present invention, the plaster finish surface can be made clean and the finish surface can be an exposed surface of the structure. For this reason, the degree of freedom of the product shape is increased, and a product that can be used in various places can be provided.

Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat II (Reference) C04B 111: 00 C04B 111: 00 (72) Inventor Hiroo Shioda 585 Tomicho, Funabashi-shi, Chiba Sumitomo Osaka Cement Co., Ltd. Within the business division (72) Inventor Shinichi Hamahira 585 Tomicho, Funabashi-shi, Chiba Sumitomo Osaka Cement Co., Ltd.Construction Materials Business Division (72) Inventor Shigeyuki Kasahara 585 Tomicho, Funabashi-shi, Chiba Pref. (72) Inventor Haruo Aoki 4-6-15 Sendagaya, Shibuya-ku, Tokyo, Japan Fujita Corporation (72) Inventor Masaya Hara 4-6-15 Sendagaya, Shibuya-ku, Tokyo Fujita Corporation (72) Inventor Teruo Okizumi 5-23-15 Sendagaya, Shibuya-ku, Tokyo, Japan (72) Inventor Shinichi Yamada 5-23-15 Sendagaya, Shibuya-ku, Tokyo F-term in Techno Materials, Inc. F-term (reference) 2E162 CA15 FD00 4G012 PA07 PB16

Claims (5)

[Claims] 1. A cement containing water, a partially or entirely dried lightweight aggregate, a water reducing agent, and at least one organic agent arbitrarily selected from cellulosic compounds and polyvinyl alcohol. A lightweight concrete for a curtain wall. 2. The curtain wall according to claim 1, wherein the water reducing agent is a polycarboxylic acid-based water reducing agent or a dispersant having a degree of dispersion equal to or higher than that of the polycarboxylic acid-based water reducing agent. Lightweight concrete. 3. The lightweight concrete for a curtain wall according to claim 1, wherein the lightweight aggregate is in a completely dry state or in a state of not more than a half of a water absorption of the lightweight aggregate. 4. The lightweight concrete for a curtain wall according to claim 1, wherein the water cement ratio is 35% or more. 5. A lightweight concrete for a curtain wall according to claim 1, 2, 3, or 4 by adjusting the composition so that the specific gravity at the time of kneading becomes 1.7 or less. A method for producing lightweight concrete for a curtain wall.