JP3562872B2 - Manufacturing method of lightweight cellular concrete - Google Patents

Description

[0001]
[Industrial applications]
The present invention relates to a method for producing lightweight aerated concrete, which is mainly composed of calcareous raw materials and siliceous raw materials, is reinforced with reinforcing bars such as reinforcing bars and wire meshes (laser nets), and is autoclaved.
[0002]
[Prior art]
Light-weight cellular concrete (hereinafter referred to as ALC) products have reinforcing bars such as reinforcing bars arranged in a required amount and in a required shape in a formwork, and pulverized calcareous and siliceous raw materials and water and foaming agents. In addition, the mixed slurry is poured into a mold frame, foamed and hardened, and the porous material is autoclaved and manufactured. The mortar slurry contains almost no air bubbles after being injected into the mold, but the foaming agent starts to foam in a very short time, and the slurry gradually starts to harden due to the hydration reaction. The slurry having the increased viscosity stably holds the generated bubbles, gradually increases in volume and expands to a predetermined volume.
[0003]
As shown in FIG. 9 and FIG. 10, a plurality of U-shaped reinforcing bars 3 each including a main bar 1 in a horizontal direction and a sub bar 2 in a vertical direction are arranged in the mold 4. Immediately before the completion of the foaming of the mortar slurry, when the upper surface of the slurry passes through the main reinforcing bar at the top of the reinforcing bars arranged in the mold, the small bubbles foamed by the foaming agent are remarkably coalesced. A bubble pool was formed just above the upper main bar, causing a significant deterioration in quality.
[0004]
For this reason, in JP-A-63-256405, after pouring a mortar slurry into a mold, a bar-shaped or plate-shaped degassing piece or the like is inserted into the slurry during foam hardening, and coarse bubbles generated at the upper part of the reinforcing bar are removed. Although it is to be removed, a part remains and a coarse void partially remains. JP-A-64-9704 attempts to remove bubbles generated in the slurry by horizontally moving in the longitudinal direction after inserting a degassing piece or the like, but cannot sufficiently remove coarse bubbles. . Japanese Patent Publication No. 2-11552 discloses a method of vibrating a bar-shaped degassing piece to promote floating of coarse bubbles to the upper surface of the mortar, but coarse bubbles partially remain.
[0005]
[Problems to be solved by the invention]
In the manufacturing method as described above, as shown in FIG. 8, air bubbles 7 are likely to be generated near the main reinforcing bar 1, and some float and disappear on the mortar surface while the mortar viscosity is low. There is a problem that the resin hardens and remains as a void, thereby deteriorating the appearance and partial strength of the panel.
[0006]
Therefore, the present invention sprays water or an aqueous solution on the mortar upper surface to delay the increase in the mortar viscosity, so that the mortar easily wraps around the reinforcing bar when passing through the reinforcing bar above the reinforcing bar while foaming, and has a low viscosity of the mortar. Mortar, and coarse bubbles generated when the mortar passes through the rebar can be efficiently removed. Furthermore, by inserting the degassing insert into the mortar, the mortar viscosity in the upper part of the reinforcing bar and its vicinity is reduced, and the generated large bubbles are easily floated on the mortar surface. The purpose is to eliminate coarse bubbles by also facilitating movement in the direction of the horizontal mortar upper surface. That is, it is an object of the present invention to release excess gas accumulated in the upper part of the reinforcing bars arranged in the mold upward to reduce the remaining of large bubbles inside the panel.
[0007]
[Means for Solving the Problems]
That is, the present invention is directed to a mold in which a plurality of reinforcing bars are arranged, injecting a mortar slurry for lightweight cellular concrete, spraying water or an aqueous solution for delaying a rise in mortar viscosity on the mortar surface, and foaming the reinforcing bars. A method for producing lightweight cellular concrete, characterized in that a degassing insert is inserted into a mortar at the upper part of the reinforced concrete and horizontal movement is performed to remove coarse bubbles at the upper part of the reinforcing bar.
[0008]
[Action]
According to the present invention, water or an aqueous solution for delaying a mortar viscosity increase is sprayed on the mortar surface before the mortar passes through the reinforcing bar above the reinforcing bar while foaming, and then after passing through the reinforcing bar above the reinforcing bar. By inserting the degassing insert into the mortar and moving horizontally, the excess gas in the bubble pool generated above the main muscle can be released upward or broken down and broken down into small bubbles. ALC quality can be efficiently and efficiently improved without using.
[0009]
【Example】
Next, the present invention will be described in more detail by way of examples.
FIG. 1 is a cross-sectional view showing an ALC panel manufactured according to the present invention, FIG. 2 is a view showing a state in which water is sprayed on the upper surface of a mortar slurry after injection, and FIG. It is a figure which shows the insertion position.
[0010]
In FIG. 2, U-shaped reinforcing bars 3 are arranged at predetermined intervals in a mold 4. The mortar slurry 5 is injected therein, and then water or an aqueous solution that acts to delay the increase in the mortar viscosity is sprayed from a water spray rod 6 attached to the support frame 16 to a part or the whole of the mold 4. A water layer 10 is formed on the mortar 5. Further, as shown in FIG. 3, after the mortar 5 injected into the mold 4 has foamed to the upper part of the mold, a degassing insert 8 having a driving means attached to the support frame 16 is provided at the upper part of the reinforcing bar 3. Inserted at the corresponding position. The insertion position of the degassing insert needs to be within ± 5 mm with respect to the center of the main muscle, taking into account the placement accuracy of the top main muscle of the reinforcement and the insertion accuracy of the degassing insert. . Also, the depth of the degassing insert to be inserted needs to reach the tip of the degassing insert not more than 20 mm above the center of the main muscle. The wiring of the driving means can be attached to the support frame 16.
[0011]
The reinforcing bar 3 used in the present invention may be a single bar formed by welding the main bar 1 and the sub bar 2 in a grid as shown in FIG. 1, or a single bar obtained by welding the main bar 1 and the sub bar 2 in a grid. May be bent into a U-shape, a cage formed by welding the main bar 1 and the sub bar 2 in a lattice shape, a cage formed by welding a spacer between them, or a lath net shape. The reinforcing bar 3 preferably has a diameter of 1 to 10 mm, more preferably 2 to 5 mm as a diameter of a reinforcing bar. If the diameter of the reinforcing bars is too small, the bending strength of the lightweight cellular concrete is not sufficient, and if it is too large, the coarse cells above the reinforcing bars become larger. As for these reinforcing bars, a plurality of reinforcing bars 3 are arranged in the mold 4 as shown in FIGS. A reinforcing bar holding rod 14 is supported by a fixed reinforcing bar holding frame 13 installed on the formwork 4, and the reinforcing bar 3 is held and fixed by the reinforcing bar holding bar 14. After the ALC mortar is hardened in the mold in this state, it can be easily removed by rotating it.
[0012]
The composition of the mortar slurry for lightweight cellular concrete of the present invention is composed of a material mainly composed of a siliceous raw material, a calcareous raw material, water and a foaming agent, for example, cement, quicklime, silica stone, gypsum, crushed debris, water, A material made of metal aluminum or the like is used, and its ratio is appropriately selected and used.
The spraying according to the present invention is to discharge the water from the watering rod so as to reach the entire upper surface of the mortar slurry poured into the mold.
[0013]
The degassing insert used in the present invention may have any shape as long as the viscosity of the mortar is reduced when a rotary motion is given, and examples thereof include a rod material, a rod-shaped rotating body, and a rod-shaped vibrating body. A bar means a long, narrow bar with a circular, square, rectangular, or polygonal cross section, or a bar with stirring blades attached to it.It breaks air bubbles generated above the main bars of reinforcing bars installed on the formwork. What is necessary is just to have a size, thickness, and surface irregularities of a certain degree. The diameter is preferably about 3 to 15 mm, particularly preferably 7 to 11 mm. The material may be any material that can withstand the viscosity of the foam-hardened mortar slurry and does not deform. Further, the bar may be a rod-shaped rotating body that is rotated by a rotating means, or the bar may be a rod-shaped vibrating body that is vibrated by a vibrating means.
[0014]
The rod-shaped rotator has an uneven surface and facilitates the movement of gas to the upper surface of the mortar. The rod-shaped rotator has a grooved spiral rod-shaped rotator 11 as shown in FIG. 6 and a stirring blade-shaped rotator 12 as shown in FIG. A drill bit or a screw-type stirring blade as shown is preferable. Further, as the driving means, for example, an electric motor, an engine, or the like is attached to the other end of the rotating shaft of the rotating body, and it is preferable that the rotating body transmits the rotating motion to the tip of the rod through the rotating shaft.
[0015]
The diameter of the rod-shaped rotating body is preferably about 3 to 15 mm, particularly preferably 7 to 11 mm. The material may be any material that can withstand the viscosity of the foam-hardened mortar slurry and does not deform.
The rotation speed of the rod-shaped rotator is preferably in the range of 200 to 2000 rpm, and more preferably in the range of 500 to 1300 rpm. When the rotation speed of the rod-shaped rotating body is low, the viscosity of the mortar is not sufficiently reduced, and coarse bubbles slightly remain. When the rotation speed is high, air is entrapped from the upper portion of the mortar, and coarse bubbles partially remain. The rotation direction of the rod-shaped rotator may be either clockwise or counterclockwise, but it is preferable that the effect of rolling up coarse bubbles is greater.
[0016]
The rod-shaped vibrator may have any shape so that the gas can easily move to the upper surface of the mortar when performing vertical or horizontal vibration with respect to the vibration axis. An attached structure is preferred. The shape of the vibrating arm may be a flat plate, a curved plate, a bar, an abacus ball or the like, and the flat plate is preferably a rectangle, a square, a rhombus, or the like.
[0017]
The vertical vibration of the rod-shaped vibrator means that the vibration direction is perpendicular to the vibration axis, and the amplitude and frequency of the vibration are appropriately within a range in which coarse bubbles can be removed. It is preferably from 1 mm to 10.0 mm, and particularly preferably from 0.5 to 5.0 mm. The frequency range is preferably from 10 times per second to 200 times per second, and particularly preferably from 30 times per second to 100 times per second. As a driving method for giving vertical vibration, for example, a vibrator for giving vibration to the vibration generating part of the rod-shaped rotating body is built in, the vibration generating part is cylindrical, and the vibration generating method is an eccentric weight method, Those having a planetary motion system or the like are preferable.
[0018]
The horizontal vibration of the rod-shaped vibrator means that the vibration direction is the longitudinal direction of the vibration transmission shaft, and the amplitude and frequency range are 0.1 mm to 3.0 mm in amplitude and 1 to 50 times in frequency per second. Preferably, the amplitude is particularly 0.5 to 2.0 mm, and the frequency is 10 to 30 times per second. As the vibration device that performs horizontal vibration, for example, a device having a configuration in which an exciter is attached to the other end of the vibration transmission unit is preferable.
[0019]
Examples of water or an aqueous solution that is sprayed to delay the increase in mortar viscosity in the present invention include, for example, a nonionic surfactant polyoxyethylene sorbitan ester (for example, trade names of Nippon Emulsifier Co., Ltd .: Newcol 82, Newcol 85). ), Alkyl sulfonates (eg, Kao Corporation: Mighty 150, Mighty V2), melamine resin sulfonates (eg, Nippon Synthetic Rubber Co., Ltd .: Dynaflow G2) Polyisoprene sulfonate (for example, product of Nippon Synthetic Rubber Co., Ltd .: Sunflow Z105), lignin sulfonate (for example, product name of Nippon Paper Industries: Sunflow, Sunflow R) And water reducing agents such as polycarboxylates (for example, trade name: Dynaflow P of Nippon Synthetic Rubber Co., Ltd.). Aqueous solution of citric acid used as various surfactants and cement retarder, further aqueous solution such as silicone used as a defoaming agent (e.g., antifoam E-200 of Kao Corporation), and the like.
[0020]
When water is used, it can be used in the form of an aqueous emulsion. As such an aqueous emulsion, there is an acrylic resin (for example, trade name: Mortac of Asahi Kasei Kogyo Co., Ltd.) and the like.
The amount of water or the like sprayed on the upper portion of the mortar slurry in the above-mentioned production method is preferably in the range of 0.005 to 0.5 ml per 1 ml of the volume of the mortar slurry injected into the mold, and particularly preferably 0.005 to 0. 0.3 ml is preferred. If the amount of water sprayed is less than 0.005 per 1 ml of mortar, the formation of heavy parts is insufficient, and if it exceeds 0.5 ml per 1 ml of mortar, There is a problem that coarse voids are formed or the degree of bulk reduction is severe, and the appearance is difficult to see at the upper end of the panel.
[0021]
When an aqueous solution or the like is used, the amount adjusted to a concentration of 1 to 20 wt% (solid content concentration) may be used in the above amount.
The time when the water or aqueous solution to be sprayed to delay the increase in the mortar viscosity is before the upper surface of the mortar passes over the upper part of the main muscle, preferably within 10 minutes, particularly preferably within 5 minutes.
[0022]
FIG. 11 is a diagram showing an example of the relationship between the foaming agent and time when mortar using aluminum powder as a foaming agent is injected into a mold. The curve of the foaming rate generally rises sharply in the early stages, gradually becomes gentler and saturates.
The time when the rod-shaped rotating body or the rod-shaped vibrating body is inserted in the present invention is at the time when the mortar in the mold is substantially foamed, that is, when the foaming rate curve reaches a saturation region (around the point A in the example of FIG. 11). To from the time when the mortar maintains the fluid state.
[0023]
The point at which mortar foaming is substantially completed varies greatly depending on the particle size, shape, and the like of the aluminum powder as the foaming agent, but is usually about 5 to 40 minutes after the mortar is injected into the mold. Further, the period when the mortar maintains the fluid state varies depending on the mortar composition, but is usually about 30 to 70 minutes after the mortar is injected into the mold.
The time at which the mortar is almost completed and the period during which the mortar is maintained can be easily determined by experiments once the aluminum powder to be used and the mortar composition are determined.
[0024]
The flow state can be determined by, for example, inserting a rod-shaped rotating body or a rod-shaped vibrating body into a mortar, moving the rod-shaped vibrating body horizontally, and immediately determining whether or not the trajectory disappears.
After inserting the degassing insert just above the top main muscle as described above, by moving horizontally in the length direction of the main muscle, excess gas in the bubble pool generated just above the main muscle Escapes upwards or breaks down into small bubbles.
[0025]
The degassing insert may be attached to a support piece in accordance with the interval of the main muscle for each main muscle row, and air bubbles present at each contact may be removed one by one, or a plurality of the support pieces, a support frame, , So that a plurality of rows of main bars can be processed at once.
[0026]
Embodiment 1
As shown in FIG. 3, the reinforcing bars 3 were arranged at equal intervals and fixed to the formwork 4.
The mold 4 was made of 35% by weight of silica, 30% by weight of cement, 8% by weight of quicklime, 2% by weight of gypsum, and 25% by weight of crushed debris. Is added and kneaded, and 1 minute later, 2.5 parts by weight of water is applied to the surface of the mortar after 1 minute (this amount corresponds to 0.025 ml of an aqueous solution per 1 ml of the volume of the mortar that has been foamed in the mold). Was sprayed. When 30 minutes have passed after the mortar was injected into the mold, the rod-shaped rotating body 11 of FIG. 6 was inserted just above the main bar 1 and linearly moved in parallel with the main bar, thereby removing the air pockets above the main bar. The process was completed by 33 minutes after the fluidity of the sample was maintained. After the mortar for ALC reached a predetermined hardness, the portion taken along the line YY ′ in FIG. 1 was cut with a piano wire and cured in an autoclave.
[0027]
As shown in FIG. 5, heavier portions 9 were arranged on the upper surface of the obtained ALC, and no exposure of coarse bubbles was observed, which was preferable. This product was cut along the line XX ′ in FIG. 1 and the cut surface was observed. As shown in FIG. 4, except that the upper part of the main bar 1 was heavier, no coarse bubbles were generated inside.
[0028]
Embodiment 2
A mortar slurry was prepared by kneading 50% by weight of silica stone, 35% by weight of ordinary Portland cement, 10% by weight of quicklime, and 5% by weight of gypsum with 100 parts by weight of 70 parts by weight of water and 0.06 parts by weight of aluminum. .
This mortar slurry is poured into a mold having a width of 600 mm, a length of 600 mm and a height of 600 mm, and after 3 minutes, a 1.1% aqueous solution of sodium polyalkylsulfonate (trade name: Mighty 150, manufactured by Kao Corporation). 5 parts by weight This amount corresponds to 0.015 ml of an aqueous solution per 1 ml of the volume of the mortar that has been foamed in the mold. ) Was sprayed. When 30 minutes have passed after the mortar was injected into the mold, the rod-shaped rotating body 11 of FIG. 6 was inserted just above the main bar 1 and linearly moved in parallel with the main bar, thereby removing the air pockets above the main bar. The process was completed by 34 minutes after the fluidity of the sample was maintained. After the mortar reached a predetermined hardness, it was cut with a piano wire and autoclaved.
[0029]
Exposure of coarse bubbles was not observed on the obtained ALC surface, which was preferable. This ALC was cut in the same manner as in Example 1 and the cut surface was observed. As a result, no coarse bubbles were generated inside.
[0030]
Embodiment 3
As shown in FIG. 3, the reinforcing bars were arranged at equal intervals and fixed to the mold.
100 parts by weight of 35% by weight of silica stone, 30% by weight of cement, 8% by weight of quicklime, 2% by weight of gypsum and 25% by weight of crushed debris, 70 parts by weight of water and 0.06 parts by weight of aluminum The added and kneaded mortar slurry was injected, and after 1 minute, 1.5 parts by weight of water (this amount corresponds to 0.015 ml of an aqueous solution per 1 ml of the volume of the mortar that had been foamed in the mold) was sprayed on the mortar surface. . When 30 minutes have passed after the mortar was poured into the mold, the rod 8 was inserted directly above the main bar 1 and linearly moved in parallel with the main bar to remove the air pockets at the upper portion of the main bar, and the fluidity of the mortar was reduced. It was completed by 33 minutes after the maintenance. After the mortar reached a predetermined hardness, it was cut with a piano wire and autoclaved.
[0031]
Exposure of coarse bubbles was not observed on the obtained ALC surface, which was preferable. This ALC was cut in the same manner as in Example 1 and the cut surface was observed. As a result, no coarse bubbles were generated inside.
[0032]
Embodiment 4
A mortar slurry was prepared by kneading 50% by weight of silica stone, 35% by weight of ordinary Portland cement, 10% by weight of quicklime, and 5% by weight of gypsum with 100 parts by weight of 70 parts by weight of water and 0.06 parts by weight of aluminum. .
This mortar slurry is poured into a mold having a width of 600 mm, a length of 600 mm, and a height of 600 mm, and after 2 minutes, 3.0 parts by weight of water is applied to the surface of the mortar (this amount is 0 wt. .03 ml of an aqueous solution). Twenty-five minutes after the mortar was poured into the mold, the rod 8 was inserted just above the main bar 1 and moved linearly in parallel with the main bar to remove the air pockets at the top of the main bar. It was completed by 28 minutes after maintaining. After the mortar reached a predetermined hardness, it was cut with a piano wire and autoclaved.
[0033]
Exposure of coarse bubbles was not observed on the obtained ALC surface, which was preferable. This ALC was cut in the same manner as in Example 1 and the cut surface was observed. As a result, no coarse bubbles were generated inside.
[0034]
Embodiment 5
A mortar slurry was prepared by kneading 45% by weight of silica stone, 40% by weight of ordinary Portland cement, 10% by weight of quick lime, and 5% by weight of gypsum with 100 parts by weight of 70 parts by weight of water and 0.06 parts by weight of aluminum. .
This mortar slurry is poured into a mold having a width of 600 mm, a length of 600 mm, and a height of 600 mm. After 4 minutes, 2.0 parts by weight of water is applied to the surface of the mortar. .015 aqueous solution). When 30 minutes have passed after the mortar was poured into the mold, the rod-shaped vibrator was inserted directly above the main bar 1 and moved linearly in parallel with the main bar, removing the air bubbles at the top of the main bar and reducing the fluidity of the mortar. It was completed by 33 minutes after the maintenance. After the mortar reached a predetermined hardness, it was cut with a piano wire and autoclaved.
[0035]
Exposure of coarse bubbles was not observed on the obtained ALC surface, which was preferable. This ALC was cut in the same manner as in Example 1 and the cut surface was observed. As a result, no coarse bubbles were generated inside.
[0036]
[Comparative Example 1]
An ALC was produced in the same manner as in Example 1 except that the rod was inserted into the upper part of the main bar and the air pockets were removed.
Exposure of coarse bubbles was observed along the main streaks on the obtained ALC surface, which was not preferable. This was cut in the same manner as in Example 1, and the cut surface was observed. As a result, it was found that coarse bubbles were also generated inside the panel.
[0037]
【The invention's effect】
In the present invention, mortar is foamed by injecting a mortar slurry for lightweight cellular concrete into a formwork in which a plurality of reinforcing bars are arranged, and spraying water or an aqueous solution on the mortar surface to delay mortar viscosity rise. Large bubbles generated when passing through the reinforcing bar above the reinforcing bar can be removed efficiently, and after the mortar foaming is completed, an insert for degassing is inserted into the upper portion of the reinforcing bar, and while moving horizontally, the upper portion of the reinforcing bar is moved. In addition, the coarse bubbles partially left in the vicinity thereof are floated on the mortar surface, and the coarse bubbles can be eliminated without remaining. That is, it is possible to easily remove the air bubbles accumulated on the upper part of the reinforcing bars arranged in the mold, eliminate nests near the surface and coarse internal air bubbles, and produce an ALC panel having a favorable appearance and strength.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing an ALC panel manufactured according to the present invention.
FIG. 2 is a cross-sectional view showing a state in which water is sprayed on an upper surface of the mortar slurry after the mortar slurry of the present invention is injected.
FIG. 3 is a cross-sectional view showing a position where the degassing insert of the present invention is inserted.
FIG. 4 is a sectional view taken along line xx ′ of FIG. 1;
FIG. 5 is a sectional view taken along the line YY ′ of FIG. 1;
FIG. 6 is a front view of the rod-shaped rotating body of the present invention.
FIG. 7 is a front view showing another example of the rod-shaped rotating body of the present invention.
FIG. 8 is a cross-sectional view of a conventional panel cut in a direction perpendicular to a main bar.
FIG. 9 is a cross-sectional view in which reinforcing bars are arranged on a formwork and viewed from a direction perpendicular to main bars.
FIG. 10 is a cross-sectional view in which reinforcing bars are arranged on a formwork and viewed from a horizontal direction with respect to main bars.
FIG. 11 is a diagram showing an example of the relationship between the foaming rate of mortar injected into a mold and time.
[Explanation of symbols]
REFERENCE SIGNS LIST 1 Main bar 2 Secondary bar 3 Reinforcing bar 4 Formwork 5 Mortar 6 Watering rod 7 Bubble reservoir 8 Degassing insert 9 Weighted portion 10 Water layer 11 Groove-shaped spiral rod-shaped rotary body 12 Stirring blade-shaped rotary body 13 Blade 14 Reinforcement Bar holding frame 15 Reinforcing bar holding bar 16 Support frame

Claims (4)

Inject the mortar slurry for lightweight cellular concrete into the formwork in which a plurality of reinforcing bars are arranged, spray water or an aqueous solution on the mortar surface to delay the increase in mortar viscosity, foam, and then insert for degassing. A method for producing lightweight cellular concrete, characterized by inserting a mortar into a mortar above a reinforcing bar and horizontally moving it to remove coarse bubbles above the reinforcing bar. 2. The method for producing lightweight cellular concrete according to claim 1, wherein the degassing insert is a rod, and the rod is inserted into a mortar above the reinforcing bar, and coarse bubbles above the reinforcing bar are removed while moving horizontally. 2. The degassing insert is a rod-shaped rotator, and the rod-shaped rotator is inserted into a mortar above the reinforcing bars, and a rotary motion is applied to remove horizontal bubbles above the reinforcing bars while moving horizontally. Manufacturing method of lightweight cellular concrete. 2. The lightweight as set forth in claim 1, wherein the degassing insert is a rod-shaped vibrator, and the coarse vibrator on the upper part of the reinforcement is removed by inserting the rod-like vibrator into the mortar above the reinforcement, applying vibration, and moving horizontally. Manufacturing method for cellular concrete.

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