JPH0355205A - Manufacture of light weight concrete board - Google Patents

Manufacture of light weight concrete board

Info

Publication number
JPH0355205A
JPH0355205A JP19161589A JP19161589A JPH0355205A JP H0355205 A JPH0355205 A JP H0355205A JP 19161589 A JP19161589 A JP 19161589A JP 19161589 A JP19161589 A JP 19161589A JP H0355205 A JPH0355205 A JP H0355205A
Authority
JP
Japan
Prior art keywords
mold
skin layer
strength
lightweight concrete
specific gravity
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP19161589A
Other languages
Japanese (ja)
Inventor
Kazumasa Fukutomi
和正 福冨
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Panasonic Electric Works Co Ltd
Original Assignee
Matsushita Electric Works Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Matsushita Electric Works Ltd filed Critical Matsushita Electric Works Ltd
Priority to JP19161589A priority Critical patent/JPH0355205A/en
Publication of JPH0355205A publication Critical patent/JPH0355205A/en
Pending legal-status Critical Current

Links

Abstract

PURPOSE:To improve the surface strength while keeping the entire strength by moving a stirring rod having a configuration corresponding to a mold surface in the direction of mold patterns, and removing bubbles in the vicinity of the mold surface of cast cement slurry. CONSTITUTION:A stirring rod 3 corresponding to the surface of a mold 2 is moved in the direction of mold patterns, so that a high gravity surface skin layer 9 is formed in removing bubbles in the vicinity of the mold surface of cast cement slurry 7. Whereby, on the surface of a light weight concrete board 10, the high gravity surface skin layer 9 having high strength can readily be formed, and without affecting low gravity parts except the skin layer 9, the light weight concrete 10 which is improved in its surface strength can be obtained while the strength is maintained.

Description

【発明の詳細な説明】 (産業上の利用分野) この発明は、軽量コンクリート板の製造方法に関するも
のである。さらに3−¥しくは、この発明は、表面強度
を向上させることができ、しかも高比重表面スキン層の
厚さを容易に調整することのできる軽量コンクリート板
の製造法に関するものである. {従来の技術} 従来より、セメントおよび水を主成分としたスラリーに
気泡を混入させた軽量コンクリート板が知られている。
DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for manufacturing lightweight concrete plates. Furthermore, the present invention relates to a method for manufacturing a lightweight concrete plate that can improve the surface strength and easily adjust the thickness of the high specific gravity surface skin layer. {Prior Art} Lightweight concrete plates made by mixing air bubbles into a slurry mainly composed of cement and water have been known.

この軽量コンクリート板どしては、軽量骨材や気泡等の
分散混入によって、比重を0.6程度に小さくした低比
重のALCやその他の各種の気泡コンクリート板が開発
されてきている。
As lightweight concrete plates, low specific gravity ALC and other various cellular concrete plates have been developed, which have a specific gravity reduced to about 0.6 by dispersing lightweight aggregate, air bubbles, etc.

このような軽量コンクリート板は、一般に、1折熟性、
吸音性等の諸性能は良好であるものの、その強度は小さ
いという欠点があるため、強度向上のための様々の方策
がこれまでにも検討されてきており、たとえば第4図に
示したような強度改傳の方法が提案されている。
Such lightweight concrete plates generally have one-fold maturity,
Although its sound absorption properties and other properties are good, its strength is low, so various measures have been studied to improve its strength, such as the one shown in Figure 4. A method of intensity modification has been proposed.

この第4図に例示した方法では、 <a)  型枠(ア)の底部に、所定形状のゴム製等の
成形型(イ)を配置し、この 型枠(ア)および戊形型(イ)の表面 に表面活性剤等の離型剤(ウ)を塗布 した後に、離型剤(ウ)を乾燥してい る。
In the method illustrated in FIG. 4, <a) A mold (b) made of rubber or the like having a predetermined shape is placed at the bottom of the mold (a), and this mold (a) and a hollow mold (i) are placed at the bottom of the mold (a). ) After applying a mold release agent (c) such as a surfactant to the surface of the mold, the mold release agent (c) is dried.

(b)  その後、軽量骨材または気泡を混入して、比
重0.6程度に調整した低比重セメントスラリー(工)
を型枠(ア) 内に注型する。
(b) After that, a low specific gravity cement slurry (process) is prepared with a specific gravity of approximately 0.6 by mixing lightweight aggregate or air bubbles.
Pour into the formwork (A).

(C)  次いで、型枠(ア)ごと全体を加振して、成
形型(イ)表面近傍の低比重 セメントスラリ−(工)中の気泡(オ)を上方へと移動
させる. (d)  前養生等の適宜な処理を行った後に、脱型す
る。
(C) Next, the entire mold (A) is vibrated to move the air bubbles (E) in the low specific gravity cement slurry (C) near the surface of the mold (B) upward. (d) After performing appropriate treatments such as pre-curing, demolding is performed.

こうすることにより、軽量コンクリート板(力)表面に
気泡混入量の少ない高比重の表面スキン層(キ)を形成
する。
By doing this, a surface skin layer (ki) with a high specific gravity and a small amount of air bubbles is formed on the surface of the lightweight concrete plate (ki).

(発明が解決しようとする課題) しかしながら、この第4図に例示したような軽量コンク
リート板(力)の表面強度の改善法の場合には、型枠(
ア)ごと全体を加振するため、その振動が低比重セメン
トスラリー(工)全体に及び、スキン層(キ)と反対側
での比重が過度に低下してその強度が落ちるという欠点
がある.その結果、脱型時等において、軽量コンクリー
ト板(力)がかけやずいという問題があった。
(Problem to be solved by the invention) However, in the case of a method for improving the surface strength of a lightweight concrete plate (force) as illustrated in FIG.
Since the entire structure (a) is vibrated, the vibration extends to the entire low-density cement slurry (work), which has the disadvantage that the specific gravity on the side opposite to the skin layer (g) decreases excessively, reducing its strength. As a result, there was a problem in that the lightweight concrete plate (force) was difficult to apply during demolding.

一方、軽量コンクリート板(力)の表面強度を向上させ
るためには、このスキン層〈キ)の厚さをある程度厚く
することが必要であるが、そのためには型枠(ア)全体
を加振する加振時間を長くしなければならない.これに
よって、かえってスキン層(キ)と反対測の比重低下が
助長されるという問題が生ずる。このため、軽量コンク
リート板(力)全体の強度を維持しつつ、しかも表面ス
キン層(キ)の強度を向上させ、その厚さを所定のもの
にコントロールするのは極めて困難であるのが実状であ
った. この発明は、以上の通りの事情に鑑みてなされたもので
あり、従来の軽量コンクリート板の表面スキン層形成の
欠点を解消し、全体の強度を維持しつつ、表面強度を向
上し、そのための高比重表面スキン層の厚さを容易に調
整することのできる、改善された軽量コンクリート板の
製造方法を提供することを目0勺としている. (課題を解決するための手段) この発明は、上記の課題を解決するものとして、成形型
表面に対応する形状の撹拌棒を型模様方向に移動させ、
注型セメントスラリーの成形型表面近傍の気泡を除去し
て高比重の表面スキン層を形成することを特徴とする軽
量コンクリート板の製造方法を提供する。
On the other hand, in order to improve the surface strength of the lightweight concrete plate (force), it is necessary to increase the thickness of this skin layer (g) to some extent, but in order to do so, the entire formwork (a) must be vibrated. The excitation time must be increased. This causes a problem in that a decrease in specific gravity, which is opposite to that of the skin layer (K), is promoted. For this reason, it is actually extremely difficult to maintain the overall strength of the lightweight concrete plate (forced), improve the strength of the surface skin layer (forced), and control its thickness to a predetermined value. there were. This invention was made in view of the above-mentioned circumstances, and aims to eliminate the drawbacks of forming a skin layer on the surface of conventional lightweight concrete plates, improve the surface strength while maintaining the overall strength, and improve the surface strength. The aim is to provide an improved method for manufacturing lightweight concrete plates in which the thickness of the high specific gravity surface skin layer can be easily adjusted. (Means for Solving the Problems) This invention solves the above problems by moving a stirring rod having a shape corresponding to the surface of the mold in the direction of the mold pattern,
Provided is a method for manufacturing a lightweight concrete plate, which is characterized in that a surface skin layer with high specific gravity is formed by removing air bubbles near the surface of a mold of cast cement slurry.

(作 用) この発明の軽量コンクリート板の製造方法においては、
成形型表面に対応ずる形状の撹拌棒を成形型の型模様に
沿って、一方向または往復移動させることによって、型
枠に注型したセメントスラリーの成形型表面近傍の気泡
を上方へと移動させる。また、気泡の一部は破壊される
場合もある.これによって、軽量コンクリート板表面に
高比重のスキン層が形成され、表面強度の向上した軽量
コンクリート板を製造することができる。この方法は、
従来法のようにセメントスラリー全体を加振する必要が
ないため、軽量コンクリート板の低比重部に悪影響を与
えることなく、高比重表面スキン層を容易に形戊するこ
とができる。また、撹拌棒の移動速度、移動回数等によ
り、軽量コンクリート板の形状、大きさ、厚さ等に応じ
た適宜な厚さの高比重表面スキン層を形成することがで
き、その層厚のコントロールも容易となる。
(Function) In the method for manufacturing lightweight concrete plates of this invention,
By moving a stirring rod with a shape corresponding to the mold surface in one direction or back and forth along the pattern of the mold, the air bubbles near the mold surface in the cement slurry poured into the mold are moved upward. . Also, some of the bubbles may be destroyed. As a result, a skin layer with high specific gravity is formed on the surface of the lightweight concrete plate, and a lightweight concrete plate with improved surface strength can be manufactured. This method is
Since there is no need to vibrate the entire cement slurry as in the conventional method, the high specific gravity surface skin layer can be easily shaped without adversely affecting the low specific gravity portion of the lightweight concrete plate. In addition, by adjusting the moving speed and number of movements of the stirring rod, it is possible to form a high specific gravity surface skin layer with an appropriate thickness depending on the shape, size, thickness, etc. of the lightweight concrete plate, and control the layer thickness. It also becomes easier.

(実施図1) 以下、図面に沿って実施例を示し、この発明の軽量コン
クリート板の製造方法についてさらに詳しく説明する. 第1図は、この発明の軽量コンクリート板の製造方法に
用いることのできる撹拌棒の一実方色例を示した斜視図
である。
(Executive Drawing 1) Hereinafter, an example will be shown along with the drawings, and the manufacturing method of the lightweight concrete plate of the present invention will be explained in more detail. FIG. 1 is a perspective view showing an example of a solid color of a stirring rod that can be used in the method of manufacturing a lightweight concrete plate of the present invention.

型枠(1)の底部に配設した所定形状のゴム製等の成形
型(2)の表面に対応する形状の撹拌棒(3)を成形型
(2)表面部に配置する,この場合、撹袢棒にはブラシ
部(4)を設けることも有効である。このブラシ部(4
)を或形型{2}にわずかに接触するように配置するこ
とができる。
A stirring rod (3) of a shape corresponding to the surface of a mold (2) made of rubber or the like having a predetermined shape arranged at the bottom of the mold (1) is placed on the surface of the mold (2). It is also effective to provide the stirring rod with a brush portion (4). This brush part (4
) can be placed slightly touching the shaped mold {2}.

このような梢成を有ずる撹拌棒(3)は、成形型{2}
の型SS方肉、すなわち、図中に示した矢印<A)方向
に往復移動自在としている.fl!拌棒(3)の成形型
(2)表面からの距離は特に限定されることはなく、製
造する軽量コンクリート板の形状、大きさ、厚さ等に応
じた適宜なものとすることができる.たとえば、ブラシ
部(4》によって2〜5間程度の距離としてもよい.ま
た、このブラシ部(4)としては、繊維状体、あるいは
第2図に例示したようなくし歯状体(5)とすることも
でき、適宜な形状とすることができる.また、その材質
についても格別の制限はない.第1図および第2図に例
示したような撹拌棒(3)の駆動方式についても特に制
限はなく、チェーン脂#vの任意の方式を採用すること
ができる。
The stirring rod (3) having such a top structure is made of a mold {2}
In other words, it is movable back and forth in the direction of the arrow <A) shown in the figure. Fl! The distance of the stirring rod (3) from the surface of the mold (2) is not particularly limited, and can be set as appropriate depending on the shape, size, thickness, etc. of the lightweight concrete plate to be manufactured. For example, the distance may be between 2 and 5 depending on the brush part (4).Also, the brush part (4) may be made of a fibrous material or a comb tooth-like material (5) as illustrated in FIG. Also, there are no particular restrictions on the material. There are also no particular restrictions on the driving method of the stirring rod (3) as illustrated in Figures 1 and 2. Instead, any method of chain fat #v can be adopted.

このような撹拌棒(3)を用いて、軽量コンクリート板
を製造する方法を例示したものが第3図である. この第3図の工程に示したように、この発明の軽量コン
クリート板の製造方法においては、<a> <b> <C> まず、型枠(1)の底部に、所定形 状のゴム製等の成形型(2)を配置し、この型枠(1)
および成形型(2)の 表面に表面活性剤等の離型剤(6)を 塗布して、強制乾燥あるいは自然乾燥 などの適宜な方法により離型剤(6) を乾燥する. 次いで、あらかじめ軽1k−i!!−材または気泡を混
入して、調製しておいたセメ ントスラリー(7)を型枠(1)内に 注型する。このセメントスラリー(7)の組成成分、そ
の成分比、また比重に ついても特に制限はないが、比重とし ては、0.8程度とすることが好ましい。
Figure 3 shows an example of a method for manufacturing lightweight concrete plates using such a stirring rod (3). As shown in the steps in FIG. 3, in the method for manufacturing a lightweight concrete plate of the present invention, <a><b><C> First, a rubber or the like having a predetermined shape is placed on the bottom of the formwork (1). The mold (2) is placed, and this mold (1)
Then, a mold release agent (6) such as a surfactant is applied to the surface of the mold (2), and the mold release agent (6) is dried by an appropriate method such as forced drying or natural drying. Next, light 1k-i in advance! ! - Pour the prepared cement slurry (7) into the formwork (1) by mixing in the material or air bubbles. Although there are no particular restrictions on the composition of this cement slurry (7), its component ratio, or specific gravity, it is preferable that the specific gravity is about 0.8.

注型後、ブラシ部(4)が成形型 (2)の表面にわずかに接触するよう に、第1図に例示した撹拌棒(3)を 配置する.もちろん、上記<a>の工 程後に攬拌棒(3)を型枠(1)内に 配備しておくこともできる。After casting, the brush part (4) is placed in the mold (2) so that it slightly touches the surface of In this case, use the stirring bar (3) illustrated in Figure 1. Deploy. Of course, the work of <a> above After a while, put the stirring rod (3) into the formwork (1). It can also be kept in place.

次いで、成形型(2)の型模様方向 に撹拌棒(3)を往復移動させる.こ の撹拌I(3)の往復移動によって、 所要の厚みと比重のス虎ン層を形成す る.撹拌棒(3)の往復移動によって、型枠(1)に江
型した、或形型(2) 表面近傍のセメントスラリー(7)中 の気泡(8)を上方へと移動させるこ とができ、高比重のスキン層を形成す ることができる. この後に、前養生等の適宜な処理を 行い、型枠(1)より脱型する。
Next, the stirring rod (3) is moved back and forth in the direction of the mold pattern of the mold (2). This reciprocating movement of stirring I (3) forms a strained layer with the required thickness and specific gravity. By reciprocating the stirring rod (3), air bubbles (8) in the cement slurry (7) near the surface of the mold (2) formed in the mold (1) can be moved upward. A skin layer with high specific gravity can be formed. After this, appropriate treatments such as pre-curing are performed, and the mold is removed from the mold (1).

<d>  必要に応じて、オートクレープ養生を行う。<d> If necessary, perform autoclave curing.

以上のようにして、表面に所要な厚 さにコントロールした高比重のスキン 層(9)を有する軽量コンクリート板 (10)を得る. 次に、この第3図に例示した方法により軽量コンクリ−
1・板を製造した具体例について説明するく製造例〉 以下に示したような組或および混水比からなるセメント
スラリーに気泡を混入して、比重0.8に調整した. ボルトランドセメント :  40% 珪石粉        ・  40% フライアッシュ    ・  20% その他の添加剤        2% 温水比        ・  40% このセメントスラリーを型枠内に注型し、撹JT棒を1
0〜20(自)/ secの移動速度で威形型の型if
A様方向に10往復させた. この後に、脱型・養生したところ、スキン層厚が500
μm、60℃でのスキン層比重が1.5、および低比重
部の比重が0.6の、均一厚みのスキン層を有する、表
面強度の向上したII量コンクリート板を!!!遣する
ことができた。脱型時における表面スキン層の剥離や軽
量コンクリート板の低比重部の破壊などは発生しなかっ
た. 表面強度の向上が図られ、表面以外の低比重部における
軽量コンクリート板の強度も安定している.スキン層の
厚さコントロールも容易であった.もちろんこの発明は
、以上の例によって限定されるものではない。撹拌棒の
形状、大きさおよびその横戒、また、その移動速度およ
び移動回数、ブラシ部等の形状、長さおよび材質、また
はセメントスラリーの組成戒分、成分比および温水比、
さらには型枠、戊形型の構造、構成等の細部については
様々な態様が可能であることはいうまでもない. (発明の効果) 以上詳しく説明した通り、この発明によって、軽量コン
クリート板表面に高強度の高比重表面スキン層を容易に
形成することができる.スキン層以外の低比重部に影響
を与えることなく、また、その強度を維持したままで表
面強度の向上した軽量コンクリート板を製造することが
できる.スキン層の厚さコントロールも容易である.
In the manner described above, a lightweight concrete plate (10) having a high specific gravity skin layer (9) with a controlled thickness on its surface is obtained. Next, use the method illustrated in Fig. 3 to construct lightweight concrete.
1. Describing a specific example of manufacturing a board Manufacturing example> Air bubbles were mixed into a cement slurry having the composition and water mixing ratio shown below to adjust the specific gravity to 0.8. Boltland cement: 40% Silica powder ・ 40% Fly ash ・ 20% Other additives 2% Hot water ratio ・ 40% This cement slurry was poured into the formwork and stirred with a JT rod.
If the movement speed is 0-20 (self)/sec, it is an imposing type.
I made 10 reciprocations in the direction of Mr. A. After this, when the mold was removed and cured, the skin layer thickness was 500.
A concrete board with improved surface strength that has a uniformly thick skin layer with a skin layer specific gravity of 1.5 and a low specific gravity part of 0.6 at μm and 60°C! ! ! I was able to send There was no peeling of the surface skin layer or destruction of the low specific gravity part of the lightweight concrete plate during demolding. The surface strength has been improved, and the strength of the lightweight concrete plate in low specific gravity areas other than the surface is also stable. It was also easy to control the thickness of the skin layer. Of course, the invention is not limited to the above examples. The shape, size and width of the stirring rod, its moving speed and number of movements, the shape, length and material of the brush part, or the composition of the cement slurry, component ratio and hot water ratio,
Furthermore, it goes without saying that various aspects are possible with respect to details such as the formwork and the structure and composition of the oval mold. (Effects of the Invention) As explained in detail above, according to the present invention, a high-strength, high-specific-gravity surface skin layer can be easily formed on the surface of a lightweight concrete plate. It is possible to manufacture lightweight concrete plates with improved surface strength without affecting low specific gravity parts other than the skin layer, and while maintaining their strength. It is also easy to control the thickness of the skin layer.

【図面の簡単な説明】[Brief explanation of drawings]

第1図は、この発明の軽量コンクリート板の製遣方法に
用いることのできる撹拌棒の一実施例を示した斜視図で
ある。第2図は、撹拌棒の別の飼を示した正面図である
。 第3図は、この発明の軽量コンクリート板の製造方法の
一実施例を示した工程断面図である,第4図は、従来法
による軽量コンクリート板の製造方法を示した工程断面
図である. 1・・・型    枠 2・・・成 形 型 3・・・撹 拌 棒 4・・・ブ ラ シ部 5・・・くし歯状体 6・・・離  型  剤 7・・・セメントスラリー 8・・・気    泡 9・・・スキン層 10・・・軽量コンクリート板
FIG. 1 is a perspective view showing one embodiment of a stirring bar that can be used in the lightweight concrete plate manufacturing method of the present invention. FIG. 2 is a front view showing another arrangement of stirring rods. FIG. 3 is a process sectional view showing an embodiment of the method for manufacturing a lightweight concrete plate according to the present invention. FIG. 4 is a process sectional view showing a method for manufacturing a lightweight concrete plate using a conventional method. 1... Form frame 2... Molding mold 3... Stirring rod 4... Brush part 5... Comb teeth 6... Mold release agent 7... Cement slurry 8 ...Air bubbles 9...Skin layer 10...Lightweight concrete plate

Claims (2)

【特許請求の範囲】[Claims] (1)成形型表面に対応する形状の撹拌棒を型模様方向
に移動させ、注型セメントスラリーの成形型表面近傍の
気泡を除去して高比重の表面スキン層を形成することを
特徴とする軽量コンクリート板の製造方法。
(1) A stirring rod having a shape corresponding to the surface of the mold is moved in the direction of the mold pattern to remove air bubbles near the surface of the mold from the cast cement slurry to form a surface skin layer with high specific gravity. Method of manufacturing lightweight concrete plates.
(2)撹拌棒に配設したブラシ部を成形型表面に接触さ
せる請求項(1)記載のコンクリート板の製造方法。
(2) The method for manufacturing a concrete plate according to claim (1), wherein a brush portion provided on the stirring rod is brought into contact with the surface of the mold.
JP19161589A 1989-07-25 1989-07-25 Manufacture of light weight concrete board Pending JPH0355205A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP19161589A JPH0355205A (en) 1989-07-25 1989-07-25 Manufacture of light weight concrete board

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP19161589A JPH0355205A (en) 1989-07-25 1989-07-25 Manufacture of light weight concrete board

Publications (1)

Publication Number Publication Date
JPH0355205A true JPH0355205A (en) 1991-03-11

Family

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Family Applications (1)

Application Number Title Priority Date Filing Date
JP19161589A Pending JPH0355205A (en) 1989-07-25 1989-07-25 Manufacture of light weight concrete board

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JP (1) JPH0355205A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103406982A (en) * 2013-08-12 2013-11-27 太原钢铁(集团)有限公司 Method for rapidly distinguishing air exhausting directions of aerated concrete blocks

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103406982A (en) * 2013-08-12 2013-11-27 太原钢铁(集团)有限公司 Method for rapidly distinguishing air exhausting directions of aerated concrete blocks

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