JP2009107274A - Method for manufacturing lightweight cellular concrete panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress the formation of foam blow holes at the upper side of an uppermost reinforcement without hindering the growth of foams inherent in ALC. <P>SOLUTION: This method for manufacturing an ALC panel comprises steps for foaming raw material slurry 2 in a form 10 with reinforcing bars 11 restricted in the vertical and horizontal positions, swinging the form 10 in a swing period including at least a partial period in a range of ≥30 mm selected from an optimum period in which the upper face of the raw material slurry 2 rises above the uppermost reinforcement 3 of reinforcing bars 11 by 20 mm, and reaches a position lower by 10 mm than the completion height of foaming to delay the coagulation of the raw material slurry 2 by swinging. When the upper face of the raw material slurry 2 reaches a position lower by 30 mm to 2 mm than the completion height of foaming, the restriction of the vertical position of the reinforcing bars 11 to the form 11 is released, and the uppermost reinforcement 3 is allowed to follow the volumetric expansion of the raw material slurry 2 to suppress the formation of foam blow holes on the upper side of the uppermost reinforcement 3. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method for producing a lightweight cellular concrete panel (hereinafter referred to as an ALC panel) by foaming a raw material slurry in a formwork in which reinforcing bars are constrained in a vertical position and a horizontal position.

  In general, when manufacturing an ALC panel, reinforcing reinforcing bars in which reinforcing bars are assembled in a lattice shape are arranged in a mold, and aluminum powder, an aqueous surfactant solution, or the like is added to a mixture of calcareous raw materials and siliceous raw materials. The raw material slurry is placed in the mold, the aluminum powder is foamed to form bubbles, and the raw material slurry is hardened while volumetrically expanding. Then, the semi-cured body after foaming is removed from the mold, sliced to a predetermined thickness, and then autoclaved, and the surface layer portion of the main cured panel is cut out to complete the ALC panel having the required dimensions.

  By the way, in the foaming process of the raw material slurry, when the upper surface of the slurry passes through the uppermost reinforcing bar of the reinforcing reinforcing bars, bubbles are struck by the reinforcing bars, and the gas emitted from the bubbles is blown into the uppermost reinforcing bars (in the formwork). The foaming nest (coarse cavity) is formed by gathering on the upper side of the reinforcing bars located in the uppermost part of the reinforcing bars and extending horizontally. As shown in FIG. 8A, the foamed nest 4 grows to a height of about 70 mm to 80 mm from the upper surface of the uppermost reinforcing bar 3 and adversely affects the strength of the cut surface 51 a of the ALC panel 51. Further, when the ALC panel 51 is cut in the extending direction of the reinforcing bar 3, as shown in FIG. 8 (b), the foamed nest 4 is exposed to the fore edge surface 51b, the appearance of the ALC panel 51 is lowered, and the commercial value is lowered.

Conventionally, the following methods have been proposed to suppress the generation of this type of foamed nest.
Patent Document 1: A method in which a rod-shaped vibrating body is inserted into a raw material slurry near the uppermost reinforcing bar and rotated or horizontally moved to reduce the viscosity of the slurry and allow excess gas to escape upward.
Patent Document 2: A method of injecting water or an aqueous solution into a raw material slurry near the uppermost rebar, delaying the viscosity increase of the slurry, and allowing excess gas to escape upward.
Patent Document 3: A method in which air is blown onto the surface of a raw material slurry, and the surface layer portion of the slurry is waved and stirred to uniformly expand the slurry.

Patent Document 4: A method in which raw material slurry immediately after placement is vibrated with a rod-like vibrator, and coarse bubbles entrained during slurry kneading are defoamed from the upper surface of the slurry.
Patent Document 5: A method in which the reinforcing bars are vibrated and the air bubbles mixed when the slurry is placed are discharged before the foaming agent in the raw material slurry starts foaming.
Patent Document 6: A method of vibrating a bottom plate of a formwork in an initial stage of foaming in which a foaming agent is partially foamed, and defoaming bubbles entrained during the placement of slurry.

JP-A-8-72035 Japanese Unexamined Patent Publication No. 7-277854 Japanese Patent Laid-Open No. 9-110548 JP-A-58-20767 JP-A-2001-232622 JP-A-60-141683

However, the conventional method has the following problems.
Patent Document 1: Since a rod-shaped vibrating body is inserted into a slurry, bubbles specific to ALC are crushed by vibration, and the crushed bubbles form new coarse bubbles above the uppermost reinforcing bars.
Patent Document 2: Since the water injection tube is inserted into the slurry, normal bubbles are crushed by the tube, and coarse bubbles are generated around the tube.
Patent Document 3: Since the stirring action by air is limited to the slurry surface layer portion, the growth of the foaming nest cannot be suppressed above the uppermost reinforcing bar at a deeper position.

Patent Document 4: Coarse bubbles entrained during slurry kneading can be defoamed by vibration immediately after the slurry is placed, but coarse bubbles generated by the slurry itself can be removed even if the slurry at a stage where the viscosity is increased is vibrated. Difficult to foam.
Patent Document 5: Similarly, it is difficult to discharge coarse bubbles even if vibration is applied to the slurry at a stage where condensation has progressed and the viscosity has increased via a reinforcing bar.
Patent Document 6: Since vibration applied to the bottom plate of the formwork is greatly damped in the vicinity of the uppermost reinforcing bar, the growth of the foaming nest generated after the upper surface of the slurry exceeds the uppermost reinforcing bar cannot be suppressed.

  An object of the present invention is to provide a method for manufacturing an ALC panel that solves the above-described problems and can effectively suppress the formation of a foaming nest above the uppermost reinforcing bar without hindering the growth of bubbles unique to ALC. .

  In order to solve the above-described problems, the method for manufacturing an ALC panel according to the present invention is such that the raw material slurry is foamed in a mold in which the reinforcing bar is constrained in the vertical position and the horizontal position, and the upper surface of the raw material slurry is the reinforcing bar. Oscillating the formwork in a swinging period including at least a partial period after exceeding the uppermost reinforcing bar (the reinforcing bar located in the uppermost part of the reinforcing bar in the formwork and extending horizontally), In addition to delaying the setting of the raw material slurry by the swing, by releasing the restraint of the vertical position of the reinforcing reinforcing bar at the end of foaming of the raw material slurry, by raising the uppermost reinforcing bar to follow the volume expansion of the raw material slurry, It is characterized by suppressing generation of a foaming nest on the upper side of the uppermost reinforcing bar.

In the above method, when the mold is swung, the raw slurry is liquefied, the aggregation of the slurry is delayed, and bubbles are distributed in the liquefied slurry. For this reason, it becomes difficult for bubbles to come into contact with the uppermost reinforcing bar, and the generation of foaming nests due to bubble breakage is suppressed.
In addition, at the end of foaming, the restraint of the reinforcing reinforcing bars in the vertical direction is released, and the uppermost reinforcing bars are raised following the volume expansion of the slurry. For this reason, it becomes difficult to produce a space | gap on the upper side of the uppermost reinforcing bar, and the production | generation of the foaming nest by foam collection is suppressed. At the end of foaming, even if the slurry is liquefied in the vicinity of the uppermost reinforcing bar, the holding strength of the reinforcing bar is strong because the slurry is condensed at a lower level. Therefore, although the lower reinforcing bar or the central height reinforcing bar of the reinforcing reinforcing bar hardly rises, the uppermost reinforcing bar rises so as to bend following the volume expansion of the slurry.

[1] Oscillation distance of mold frame Here, the oscillation distance of the mold frame is not particularly limited, but is preferably 0.3% to 10% of the length of the mold frame in the oscillation direction. The size of the mold is not particularly limited. For example, a standard mold used in an actual manufacturing facility has a length of about 6000 mm and a width of about 1500 mm. The distance when the mold is swung in the length direction is about 18 mm at 0.3% and about 600 mm at 10%. The distance when swinging in the width direction is about 4.5 mm at 0.3% and about 150 mm at 10%.

  When the rocking distance of the mold is 0.3% to 10% of the length in the rocking direction, the whole raw material slurry shakes greatly in the mold, the slurry condensing is delayed, and bubbles are uniformly distributed in the slurry. It becomes easy to do. When the rocking distance is less than 0.3%, the moving distance of the slurry is insufficient, the condensation progresses, the flowability of the bubbles is lowered, and the foamed nest tends to be generated. When the rocking distance exceeds 10%, the effect of delaying the setting does not change, but the rocking equipment becomes large-scale. The rocking distance of the mold is more preferably 1% to 5% in that the setting can be effectively delayed with a small rocking equipment.

[2] Swing direction of mold frame The swing direction of the mold frame is not limited to a specific direction, and it is sufficient that the raw slurry moves within the mold frame. The length direction, the width direction, the diagonal direction, and the vertical direction of the mold frame Any of the directions may be used, and the rotation may be performed in a horizontal plane.

[3] formwork rocking acceleration of the swinging acceleration formwork is not particularly limited, and is preferably ^{0.001m / s 2 ~0.2m / s 2} . In general, the raw material slurry placed in the mold is in a state in which mixing is resisted by the frictional force between particles such as silica, cement, and quicklime. In this state, swinging the formwork and shaking the slurry breaks the contact between the particles, and water is evenly distributed in the slurry. Therefore, the slurry is liquefied and the setting speed of the slurry is that of natural foaming. Than can be delayed. However, if the rocking acceleration of the mold is less than 0.001 m / s ² , the slurry follows the rocking of the mold, the particles are kept in contact with each other, and the aggregation is difficult to reduce the viscosity of the slurry. Tend to be.

On the other hand, the raw material slurry generates ALC-specific bubbles with the reaction between the aluminum powder and the alkaline substance. Since these bubbles are very fragile to shocks and vibrations, we want to keep the impact on the slurry as low as possible during the bubble growth process. When the rocking acceleration of the mold exceeds 0.2 m / s ² , normal bubbles are easily destroyed by impact. In that it can reliably prevent and foam breaking to lower the slurry viscosity, the rocking acceleration of the mold is more preferably ^{0.01m / s 2 ~0.1m / s 2} .

[4] Mold swinging period The mold swinging period may be only a partial period after the upper surface of the raw material slurry exceeds the uppermost reinforcing bar of the reinforcing reinforcing bars, or in addition to this partial period and before that. A predetermined period before or after may be included.
This partial period is a period from when the upper surface of the raw material slurry exceeds 20 mm from the uppermost reinforcing bar to the position where it is 10 mm lower than the foaming end height (in this specification, suppression of the foaming nest due to oscillation during the same period) It is preferably a period of 30 mm or more selected from the “optimal period” because the effect is best exhibited. This optimum period corresponds to the period during which the foamed nest grows when the raw material slurry spontaneously foams, and is defined because it is most effective to swing during this period. Next, it will be described in detail for the beginning and the end.

[4-1] About the beginning of the optimum period The generation time of the foaming nest varies depending on the composition of the raw material slurry and the height of the foaming end. Usually, as shown in FIG. After exceeding the reinforcing bar 3, the air bubbles collided with the reinforcing bar 3 and start to form a foamed nest 4 immediately above the reinforcing bar 3. However, in the foaming process before the upper surface of the slurry 2 exceeds the uppermost reinforcing bar 3 by 20 mm, the viscosity of the slurry 2 is low, and the internal bubbles rising together with the slurry 2 do not break even when contacting with the reinforcing bar 3. Therefore, the foaming nest 4 is difficult to occur. Therefore, at this stage, even if the mold is swung, the meaning of foaming nest suppression is weak. Therefore, the start of the optimum period is when the upper surface of the slurry 2 exceeds the uppermost reinforcing bar 3 by 20 mm.

[4-2] End of Optimal Period Foaming nests grow as the raw material slurry congeals, that is, as the slurry viscosity increases. As shown in FIG. 1 (b), when the upper surface of the slurry 2 further rises, the slurry viscosity around the uppermost reinforcing bar 3 rises, bubble breakage progresses, and the foam nest 4 continues to grow. As shown in FIG. 1C, when the upper surface of the slurry 2 approaches the foaming end height (H), the viscosity of the slurry around the uppermost reinforcing bar 3 becomes considerably high, so that foam breaks up, 4 is formed as a large gap 4 a on the uppermost reinforcing bar 3. Thereafter, the slurry 2 slightly rises over a relatively long time and finishes foaming. Even if the mold is swung just before the end of foaming, the viscosity of the slurry around the uppermost reinforcing bar 3 is unlikely to decrease, so it is less meaningful to suppress the foaming nest. Therefore, the end of the optimum period is when the upper surface of the slurry 2 reaches a position 10 mm lower than the foaming end height (H).

[4-3] Range of a partial period selected from the optimal period If the formwork is swung in a partial period appropriately selected from the above optimal periods, a foaming nest suppression effect can be obtained. The range of the period (range as viewed from the progress of the upper surface of the slurry) is preferably 30 mm or more, and more preferably 50 mm or more. When the mold is swung only during a period of less than 30 mm, not only the portion that can suppress the foaming nest but also the portion that cannot be suppressed tends to be generated. On the other hand, the upper limit of the same range is limited by how much the foam end height of the slurry is higher than the uppermost reinforcing bar. For example, when the upper limit is 140 mm, the same range can be set up to 110 mm. In this case, the same range is up to 40 mm.

[5] Continuous rocking and intermittent rocking During the partial period, the mold may be rocked continuously without resting, or may be rocked intermittently by setting a pause time. However, in the case of intermittent rocking, it is desirable that the total time of the rocking is 50% or more of a part of the period, and that the pause time of the rocking is 2 minutes or less. When the total rocking time is less than 50%, compared with the case of continuous rocking, the agglomeration of the slurry proceeds and the liquefaction tends to hardly proceed. Further, if the swinging of the formwork is stopped for more than 2 minutes, the condensation of the slurry proceeds, and it becomes difficult to suppress the increase in viscosity.

[6] Timing of releasing the restraint of the vertical position of the reinforcing reinforcing bars As described above, at the end of foaming of the raw material slurry, the slurry viscosity increases around the uppermost reinforcing bars. If the reinforcing reinforcing bar is constrained in the vertical direction by the formwork at this time, a gap is formed above the reinforcing bar in the process in which the raw slurry passes through the fixed uppermost reinforcing bar. For example, when the swinging is finished at a position where the upper surface of the raw material slurry is 10 mm lower than the foaming end height, along with the subsequent volume expansion, as shown in FIG. Void 4a remains. This gap 4a runs along the uppermost reinforcing bar 3 and is inherently present as a cracked foam nest 4 in the length direction of the ALC panel 1 after completion. Therefore, in the present invention, at the end of foaming of the raw slurry, the means for restraining the vertical position of the reinforcing reinforcing bar (for example, a restraining member such as a rod pin) is operated to the release position to release the restraining of the reinforcing reinforcing bar in the vertical direction. As shown in FIG. 1E, the foaming nest 4 on the upper side of the uppermost reinforcing bar 3 is made as small as possible.

  The timing for releasing the restraint of the vertical position of the reinforcing reinforcing bar is preferably when the upper surface of the slurry reaches a position 30 mm to 2 mm lower than the foaming end height at the end of foaming of the raw material slurry. When paying attention to the viscosity of the raw slurry, it is preferable that the timing of releasing the restriction of the vertical position of the reinforcing reinforcing bar is when the slurry viscosity reaches 55% to 84% of the viscosity at the end of foaming. At a stage where the upper surface of the slurry is lower than the position 30 mm lower than the foaming end height, or at a stage where the slurry viscosity is less than 55%, since the holding force of the reinforcing reinforcing bars by the slurry is weak, when the restraint of the vertical position of the reinforcing reinforcing bars is released, As the slurry shakes, the possibility that the position of the reinforcing reinforcing bar with respect to the formwork will be increased. At the stage where the upper surface of the slurry is higher than the position 2 mm lower than the foaming end height, or the stage where the slurry viscosity is more than 84%, the slurry holds the reinforcing bar firmly, so the vertical position of the reinforcing bar is restrained. Even if it cancels | releases, the uppermost reinforcement cannot follow the volume expansion of a slurry. For this reason, the timing of releasing the restraint of the reinforcing bar in the vertical direction is when the upper surface of the slurry reaches a position 24 mm to 4 mm lower than the foaming end height, or the slurry viscosity is 61% to 79% of the viscosity at the end of foaming. It is more preferable that the time is reached.

  According to the method for producing an ALC panel of the present invention, the mold is swung to uniformly distribute bubbles in the liquefied raw material slurry, and bubble breakage due to contact with the uppermost reinforcing bar is suppressed. In addition, the restraint of the reinforcing bar in the vertical direction is released at the end of foaming, the uppermost reinforcing bar is raised following the volume expansion of the slurry, and the gap above the uppermost reinforcing bar is reduced. Therefore, there is an effect that it is possible to manufacture an ALC panel having a high commercial value that is excellent in appearance and strength by suppressing the generation of foaming nest in a timely manner without crushing ALC-specific bubbles.

  As shown in FIG. 2, the manufacturing method of the ALC panel according to the embodiment of the present invention foams the raw slurry 2 in the mold 10 in which the reinforcing reinforcing bars 11 are restrained in the vertical position and the horizontal position, and the raw slurry 2 In the swinging period including at least a partial period in the range of 30 mm or more selected from the optimal period from the upper surface of the reinforcing bar 11 exceeding the uppermost reinforcing bar 3 of the reinforcing bar 11 to 20 mm lower than the foaming end height. 10 is swung, and the setting of the raw material slurry 2 is delayed by the rocking. In addition, when the upper surface of the raw material slurry 2 reaches a position 2 mm to 30 mm lower than the foaming end height, the restraint of the reinforcing bar 11 in the vertical direction is released, and the uppermost reinforcing bar 3 follows the volume expansion of the raw material slurry 2. Let it rise. Therefore, the formation of the foaming nest on the upper side of the uppermost reinforcing bar 3 is suppressed.

  Next, the said manufacturing method is demonstrated in detail based on an Example. In this example, three ALC panels 1 were manufactured using an experimental mold 10 as shown in FIGS. The mold 10 has a length of 1000 mm, a width of 350 mm, and a height of 700 mm. The ALC panel 1 has a length of 840 mm, a width of 600 mm, and a thickness of 100 mm. The ALC panel 1 is manufactured with the length direction being horizontal and the width direction being vertical.

  In manufacturing this panel 1, first, three sets of reinforcing bars 11 were set inside the mold 10. Each reinforcing bar 11 was assembled in a lattice pattern with a main bar 12 extending horizontally in the length direction of the mold 10 and a secondary bar 13 extending vertically in the height direction of the mold 10 (the width direction of the panel 1). Two reinforcing bar mats are connected by upper and lower connecting bars 14, and the whole is formed into a cage shape. Reinforcing bars having a diameter of 5 mm are used for the main bars 12, the auxiliary bars 13, and the connecting bars 14.

  As shown in FIG. 5, the upper and lower connecting bars 14 each have two long bars 14a spanned between the two reinforcing bar mats, and two long bars 14a spanned between the long bars 14a. It is assembled in a cross-beam shape by the short bars 14b. Since the distance between the two short bars 14b of the upper connecting bar 14 is larger than the diameter of the rod pin 15, the rod pin 15 is inserted (freely inserted) between the two bars (inside the central portion of the cross beam). The distance between the short bars 14b of the lower connecting bars 14 is smaller than the diameter of the rod pin 15 and larger than the diameter of the latch pin 19 projecting from the lower end of the rod pin 15 (thinner than the rod pin 15). The lower end portion of the rod pin 15 is in contact with the upper surface of the pin, and the latch pin 19 is inserted (freely inserted) from above between the two. By inserting these upper and lower stages, the horizontal position of the reinforcing reinforcing bars 11 is constrained. The latch pin 19 is a latch portion 19a that is bent sideways after the insertion between the two pins.

  The upper end of the rod pin 15 protrudes above the mold 10 through the insertion hole 16a of the plate 16, and a handle 17 for rotating the rod pin 15 is fixed to the protruding portion 15c. Both ends of the plate 16 are supported on the upper surface of the mold 10 (see FIG. 3), and the rod pin 15 is suspended below the plate 16 by a handle 17. At the tip of the handle 17, a locking piece 17 a that is locked to the lower surface of the plate 16 when the handle 17 is rotated to the restraining position is formed.

  When the handle 17 is operated and the rod pin 15 is rotated to the restraining position shown in FIG. 5A, the locking piece 17a of the handle 17 is locked to the lower surface of the plate 16 and the rod pin 15 itself is prevented from rising. Since the lower end portion of the rod pin 15 abuts on the short bar 14b of the lower connecting bar 14 from above and the hook part 19a of the hook pin 19 hooks below the short bar 14b, the reinforcing reinforcing bar 11 However, the vertical movement of the reinforcing reinforcing bars 11 is restricted.

  When the handle 17 is operated and the rod pin 15 is rotated to the release position shown in FIG. 5B (hereinafter, this operation is referred to as “pin return”), the locking piece 17 a of the handle 17 is attached to the lower surface of the plate 16. Since the rod pin 15 itself can be lifted off the hook pin 19, the latching portion 19 a of the latch pin 19 is disengaged from the short bar 14 b, and the connecting bar 14 can move the rod pin 15 up and down. It will be in the state which can be moved up and down, ie, the restriction | limiting of the vertical position of the reinforcing steel bar 11 is released. However, since the viscosity of the slurry is high at the end of foaming to perform this pinning, even if the latching portion 19a is detached from the short bar 14b, the reinforcing bar 11 does not sink, and the reinforcing bar 11 is entirely ( As a result, the uppermost reinforcing bar 3) can be raised following the volume expansion of the raw slurry 2. The reason why the latching portion 19a is removed from the short bar 14b is to pull out the rod pin 15 thereafter.

  Then, as shown in FIG. 4, using a plurality of rod pins 15, three sets of reinforcing bars 11 were suspended inside the mold 10 at equal intervals. At this time, the foaming end height of the raw slurry 2 is set to 660 mm (target value), and this height is 140 mm higher than the uppermost reinforcing bar 3 of the main reinforcing bars 12, that is, the uppermost reinforcing bar 3 is Each reinforcing bar 11 was set so as to be 520 mm higher than the bottom surface of the mold 10.

  Next, the raw material slurry 2 was placed inside the mold 10. In the following comparative examples, reference examples and examples, as raw material slurry 2, 40 parts by mass of silica powder, 15 parts by mass of cement, 10 parts by mass of quicklime powder, 5 parts by mass of gypsum, 20 parts by mass of crust, 10 parts by mass of ALC crushed powder A mortar slurry in which 70 parts by mass of water and 0.06 parts by mass of aluminum powder (foaming agent) were added to the solid content consisting of parts and sufficiently kneaded with a mixer was used.

  Subsequently, the raw material slurry 2 was foamed in the mold 10 in which the reinforcing reinforcing bars 11 were constrained in the vertical position and the horizontal position. In this foaming process, the methods of Comparative Examples 1 to 5 in which the mold 10 is not swung, the methods of Reference Examples 1 to 5 in which the mold 10 is swung and the pin is turned back at the end of foaming, and the mold 10 is swung. Then, the methods of Examples 1 to 4 in which pinning is performed at the end of foaming were applied. Then, after the foaming and volume expansion of the slurry 2 are completed, the ALC semi-cured product 2 is taken out from the mold 10 and cut with a piano wire, and is finally cured by normal autoclave curing, and the three ALC panels 1 are assembled. completed.

<Comparative Example 1>
In Comparative Example 1, the reinforcing bar 11 is restrained in the vertical direction and the horizontal position in the mold 10 with the rod pin 15 (see FIG. 5a), and the mold 10 and the reinforcing bar 11 are kept stationary over the entire foaming period, and the raw material slurry 2 was naturally foamed. And as shown in FIG. 6, the foaming height and toughness (viscosity) of the raw material slurry 2 were measured during the foaming period. When measuring the strength, an aluminum scale 21 having a diameter of 4 mm and a length of 400 mm as shown in FIG. 7 is used. When this is gently submerged in the raw slurry 2 and stopped naturally, The length protruding from the upper surface was measured to obtain the penetration value (mm).

  Further, as shown in FIG. 8A, the completed ALC panel 51 is cut in the vertical direction at an arbitrary position in the width direction, and the upper end of the panel 51 is turned in the horizontal direction as shown in FIG. 8B. The foamed nest 4 was observed in the longitudinal section 51a and the transverse section 51b. As a result, as shown in FIG. 8A, the foamed nest 4 stood up to a height of about 70 mm from the uppermost reinforcing bar 3 in the longitudinal section 51a.

  As for the cross section 51b, as shown in FIG. 8B, the three ALC panels 51 were cut so that the cover height T from the uppermost reinforcing bar 3 was 10 mm, 20 mm, 30 mm, and 70 mm. And the score X was evaluated based on the following reference | standard regarding the length X of the foaming nest 4 longest in the extending | stretching direction of the uppermost reinforcing bar 3 among the foaming nests 4 which appeared on the cut surface. The evaluation results are shown in Table 1.

Evaluation criteria X> 20 mm 4 points 20 mm ≧ X> 10 mm 3 points 10 mm ≧ X> 5 mm 2 points 5 mm ≧ X> 2 mm 1 point No foaming nest 0 points

<Reference Example 1>
In Reference Example 1, as shown in FIG. 4, the reinforcing bar 11 is constrained in the vertical position and the horizontal position on the mold 10 with the rod pins 15, the mold 10 is placed on the carriage 18, and the upper surface of the raw material slurry 2. After passing over the uppermost reinforcing bar 3, the mold 10 together with the carriage 18 was swung on the floor surface by the examiner. Then, when foaming was completed, the pin was turned back, the mold 10 was removed, and three ALC panels were completed. The rocking conditions are as follows. In an actual manufacturing facility, the above-mentioned large formwork can be placed on a moving body such as a roller conveyor and can be driven by a swing device using a motor or a fluid pressure cylinder.

Oscillating condition Oscillating period: Period from when the upper surface of the raw material slurry 2 exceeds the uppermost reinforcing bar 3 to 20 mm lower than the foaming end height Oscillating time: 100% of the oscillating period (not resting for about 20 minutes) Continuously rocking)
Oscillating direction: horizontal direction perpendicular to the extending direction of the uppermost reinforcing bar 3 (width direction of the mold 10)
Oscillating distance: About 5% (about 17.5 mm) of the width of the mold 10
Swing acceleration: 0.07m / s ²
Swing cycle: 120 cycles per minute

  Similarly to Comparative Example 1, the foaming height and toughness of the slurry 2 were measured during the foaming period of the raw slurry 2. The measurement results are shown in FIG. Further, as shown in FIG. 10, the completed ALC panel 1 was cut in both the vertical and horizontal directions, the formation state of the foamed nest 4 in the vertical cross section 1a and the horizontal cross section 1b was observed, and evaluated in the same manner as in Comparative Example 1. The evaluation results are shown in Table 2.

  In the ALC panel 1 of Reference Example 1, the foamed nest 4 of the longitudinal section 1a was within a length of 25 mm or less from the uppermost reinforcing bar 3 in all three panels 1, 2, 3 (see FIG. 10a). As shown in Table 2, in the cross section 1b, a foam nest 4 having a length of 5 to 7 mm appears at a cover height of 10 mm of the panel 1, and a foam nest having a length of 2, 3 mm at a cover height of 10 mm of the panels 2 and 3. 4 was scattered. At the cover height of 20 mm, the foamed nest 4 having a length of 2-3 mm appeared on the panel 1, but the foamed nest 4 did not appear on the panels 2 and 3. At the cover heights of 30 mm and 70 mm, the foaming nest 4 did not appear in all three sheets. When Table 1 is compared with Table 2, it can be seen that the formation of the foamed nest 4 is effectively suppressed by the swing of the mold 10.

  Next, the qualitative change given to the raw material slurry 2 by the swing of the mold 10 is confirmed based on FIGS. FIG. 11 shows the change over time in the foaming height of the raw slurry 2 in Comparative Example 1 and Reference Example 1, and FIG. 12 shows the change over time in the strength. 11 and 12, the measurement data of Comparative Example 1 shown in FIG. 6 and the measurement data of Reference Example 1 shown in FIG. 9 are cited.

  As shown in FIG. 11, the foaming height of the raw material slurry 2 changes in substantially the same way between Comparative Example 1 and Reference Example 1, and no significant difference is observed. Moreover, the temperature change of the raw material slurry was almost the same in Comparative Example 1 and Reference Example 1. From this, it can be seen that the swing of the mold 10 does not affect the hydration reaction of the raw slurry 2. On the other hand, as shown in FIG. 12, the strength of the raw material slurry 2 shows a significant difference between Comparative Example 1 and Reference Example 1 in terms of penetration value.

  The penetration value of the reference example 1 rises more slowly than the comparative example 1 from the beginning of the mold swing period, and a large difference is generated between the penetration value of the comparative example 1 at the end of the mold swing period. Further, the penetration value of Reference Example 1 accelerates the increase immediately after the swing of the mold 10 is finished, and shows the same value as that of Comparative Example 1 when the foaming of the raw material slurry 2 is finished. From these facts, the rocking of the mold 10 does not affect the foaming period of the raw slurry 2 and the hardness of the ALC semi-cured product, and temporarily delays the setting of the slurry 2, thereby effectively producing the foamed nest 4. It can be seen that it can be suppressed.

<Reference Example 2>
In Reference Example 2, the same mold 10 and carriage 18 as in Reference Example 1 are used, the reinforcing pin 11 is restrained by the rod pin 15 in the vertical and horizontal positions on the mold 10, and the upper surface of the raw material slurry 2 is the uppermost part. After passing the rebar 3, as shown in FIG. 13, the mold frame 10 is swung in a direction, distance, acceleration and cycle different from those of the reference example 1, and the pin is turned back at the end of foaming. Three ALC panels were completed. And the completed ALC panel was cut | disconnected to the vertical and horizontal direction similarly to the reference example 1, and the production | generation state of the foaming nest in a vertical cross section and a cross section was observed and evaluated. The rocking conditions are shown below, and the evaluation results are shown in Table 3.

Oscillating condition Oscillating period: Period from when the upper surface of the raw material slurry 2 exceeds the uppermost reinforcing bar 3 to 20 mm lower than the foaming end height Oscillating time: 100% of the oscillating period (not resting for about 20 minutes) Continuously rocking)
Oscillating direction: direction that coincides with the extending direction of the uppermost reinforcing bar 3 (length direction of the mold 10)
Swing distance: about 3% of the length of the mold 10 (about 30 mm)
Swing acceleration: 0.03m / s ²
Swing cycle: 60 cycles per minute

  In the ALC panel 1 of Reference Example 2, almost the same as in Reference Example 1, the three foamed nests in the longitudinal section of the panel were within a length of 25 mm or less from the uppermost reinforcing bar. As shown in Table 3, in the cross section of the panel, a foam nest 4 having a length of 5 to 7 mm appears at a cover height of 10 mm of the panels 1 and 3, and a foam nest having a length of 2 to 3 mm at a cover height of 10 mm of the panel 2 4 was scattered. At the cover height of 20 mm, the foamed nest 4 having a length of 2-3 mm appeared on the panels 1 and 3, but the foam nest 4 did not appear on the panel 2. At the cover heights of 30 mm and 70 mm, no foaming nest appeared in all three sheets. From the comparison between Table 2 and Table 3, it can be seen that the difference in the swinging direction of the mold 10 does not significantly affect the foaming nest suppression effect.

<Reference Example 3>
In Reference Example 3, the mold 10 was swung by two methods that differed only in the rocking time among the rocking conditions of Reference Example 1.
In the first method, the mold 10 is intermittently rocked by setting a rocking pause time of less than 2 minutes at a time so that the total rocking time is 50% (about 10 minutes) of the rocking period. It moved.
In the second method, after ensuring a total rocking time of 50% or more, the mold 10 was rocked intermittently by setting a rocking pause time of 2 minutes or more at a time. FIG. 14 shows the effect of the change in the swing time on the strength of the raw slurry 2.

  As is clear from FIG. 14, both the first method and the second method of Reference Example 3 have the effect of slowing the penetration rate increase rate, that is, the progress of condensation, as compared with Comparative Example 1. However, in the case of the first method of Reference Example 3, the penetration speed of the penetration value is slightly faster than that of Reference Example 1 that continuously swings. In the case of the second method of Reference Example 3, the penetration speed of the penetration value is further accelerated, particularly during the mold swing period. Therefore, in order to more effectively suppress the foaming nest, the total swing time of the mold 10 is 50% or more of the swing period, and the swing of the mold 10 is 2 minutes or more throughout the swing period. It can be seen that it is desirable not to pause continuously.

<Reference Example 4>
In Reference Example 4, the foaming end height (target value) of the raw slurry was set 140 mm higher than the uppermost reinforcing bar 3 as in Reference Example 1. Of the swing conditions of Reference Example 1, only the swing period was set. The mold 10 was rocked by three different methods.

  In the first method, the mold 10 is in a period in which the upper surface of the slurry is located 0 mm to 30 mm above the uppermost reinforcing bar 3 (a period from immediately after exceeding the uppermost reinforcing bar 3 until reaching a position 110 mm lower than the foaming end height). Rocked. In this case, as shown in FIG. 15 (a), the ALC-specific bubbles were uniformly distributed in the vertical section 1a of the finished product, but a foaming nest 4 having a length of 55 mm was generated.

  In the second method, in a period in which the upper surface of the raw material slurry 2 is positioned 60 mm to 90 mm above the uppermost reinforcing bar 3 (a period from reaching the position 50 mm lower than the foaming end height after exceeding the uppermost reinforcing bar 3 by 60 mm). The mold 10 was swung. In this case, as shown in FIG. 15B, the state of the bubbles was good, and the foam nest 4 was shortened to a length of 40 mm.

  In the third method, in a period in which the upper surface of the raw material slurry 2 is positioned 60 mm to 120 mm above the uppermost reinforcing bar 3 (period from reaching the position 20 mm below the foaming end height after exceeding the uppermost reinforcing bar 3 by 60 mm). The mold 10 was swung. As a result, as shown in FIG. 15C, the state of the bubbles was good, and the foaming nest 4 was shortened to a length of 25 mm.

  Thus, in Reference Example 4 in which the foam end height is 140 mm higher than the top rebar 3, the optimum period of time from when the slurry exceeds 20 mm from the top rebar 3 to the position 10 mm lower than the foam end height is The ALC panel 1 excellent in both appearance and strength can be obtained by swinging the mold 10 during a partial period in the range of 30 mm or more selected from the above (second or third method). It was confirmed that the wider is more preferable.

  In Comparative Examples 2 to 5 below, the influence of the conventional method for suppressing the foaming nest on the growth of bubbles unique to ALC is verified, and the superiority of the method of shaking the mold 10 is confirmed.

<Comparative example 2>
In Comparative Example 2, as shown in FIG. 16A, the upper part of the slurry 2 was stirred using a rake 23 during a period in which the upper surface of the raw material slurry 2 was positioned 90 mm to 115 mm above the uppermost reinforcing bar 3. . As a result, as shown in FIG. 16 (b), the foaming nest 4 was shortened to a length of about 10 mm, but a large number of large bubbles 6 that can be called foaming nests are wide on the upper side of the uppermost reinforcing bar 3. Had spread to the range. This is a result of crushing the air bubbles peculiar to ALC, which significantly reduces the commercial value.

<Comparative Example 3>
In Comparative Example 3, as shown in FIG. 17A, when the upper surface of the raw material slurry 2 reached about 30 mm above the uppermost reinforcing bar 3, water was sprayed with a watering device 24. As a result, as shown in FIG. 17B, the state of the bubbles appearing in the panel longitudinal section 1a was good, but the foaming nest 4 had grown to a length of about 70 mm, which was the same as in Comparative Example 1, and was suppressed. The effect could not be confirmed.

<Comparative example 4>
In Comparative Example 4, as shown in FIG. 18 (a), a watering agent 24 and a rake 23 are used together in a period in which the upper surface of the raw material slurry 2 is located 30 mm to 70 mm above the uppermost reinforcing bar 3, and the slurry 2 is sprinkled. Stir while stirring. As a result, as shown in FIG. 18 (b), the length of the foaming nest 4 was shortened to about 50 mm, but a bubble-free portion 7 having a height of about 30 mm was generated on the upper side of the foaming nest 4 and further to the upper side. Coarse bubbles 6 were scattered. This is a result of the bubbles being crushed over a wide range by the synergistic action of watering and stirring, which worsens the appearance of the bubbles.

<Comparative Example 5>
In Comparative Example 5, as shown in FIG. 19 (a), during the period in which the upper surface of the raw slurry 2 is located 90 mm to 120 mm above the uppermost reinforcing bar 3, the vibrator 25 attached on the plate 16 and the vibration plate 26 A vibration of about 200 Hz was applied to the reinforcing steel bar 11 through the rod pin 15. As a result, as shown in FIG. 19B, the state of the bubbles was almost good, but the foaming nest 4 was as long as 65 mm, and the suppression effect could not be confirmed. The upper end portion of the foamed nest 4 is not a coarse bubble generated as the slurry viscosity increases, but the bubble in the slurry that has passed through the uppermost reinforcing bar 3 is crushed by vibration during the vibration period by the vibrator 25. It is a coarse bubble.

  Unlike the comparative examples 2-5, the method by the rocking | fluctuation of the said reference examples 1-4 does not use the means to contact the raw material slurry 2 of a foaming process directly. In addition, the swing method is not a method of physically destroying the foamed nest 4 that has been generated, but a method of suppressing the generation of the foam nest 3 by shaking the raw slurry 2. Therefore, the ALC panel 1 having an excellent appearance can be manufactured by uniformly distributing the liquefied slurry without crushing the bubbles unique to the ALC.

  Next, Examples 1 to 4 of the present invention will be described together with Reference Example 5 and Comparative Example 6. In each example, the mold 10 was swung under the same conditions, and the pins were returned at different timings. FIG. 20 shows the pin return timing. Further, the foaming height and the tensile strength of the raw material slurry 2 were measured at three points: when the swing of the mold 10 was finished, when the pin was turned back, and when foaming was finished. Table 4 shows the measurement results. And the completed three ALC panels 1 were cut | disconnected, the foaming nest 4 of the longitudinal cross section and the cross section was observed, and it evaluated by the above-mentioned reference | standard. The evaluation results are shown in Tables 5 to 9.

  In FIG. 20, “foaming height” indicates the distance from the foaming end height (0 mm) of the raw slurry 2 to the upper surface of the slurry. In Table 4, “foaming height” indicates the height from the bottom surface of the mold 10 to the top surface of the slurry. In FIG. 20 and Table 4, “penetration value” indicates the slurry viscosity measured using a scale 21 (see FIG. 7) having a length of 400 mm. In Examples 1 to 4, Reference Example 5, and Comparative Example 6, the foaming end height of the raw slurry 2 was set to 670 mm (target value).

Oscillation condition oscillation period: A period from when the upper surface of the raw material slurry 2 exceeds the uppermost reinforcing bar 3 by 20 mm to reach a position 10 mm lower than the foaming end height (optimal period of oscillation shown in FIG. 2)
Oscillation time: 100% of the oscillation period (continuous oscillation without resting for about 24 minutes)
Oscillating direction: direction that coincides with the extending direction of the uppermost reinforcing bar 3 (length direction of the mold 10)
Swing distance: about 1% of the length of the mold 10 (about 10 mm)
Swing acceleration: 0.05m / s ²
Swing cycle: 40 cycles per minute

<Comparative Example 6>
As shown in Table 4 and FIG. 20, in Comparative Example 6, when the upper surface of the slurry reaches a position 34 mm lower than the foaming end height, the pin is turned back and the upper and lower sides of the reinforcing reinforcing bars 11 are moved during the swinging period of the mold 10. The restriction of the direction position was released. At this time, the penetration value was 184 mm, which was as low as 51% of the penetration value at the end of foaming. As a result, the reinforcing reinforcing bars 11 shook together with the liquefied slurry, and the position of the reinforcing reinforcing bars 11 with respect to the mold 10 was greatly displaced. The completed ALC panel 1 could not be recognized for commercial value without evaluating the foaming nest.

<Example 1>
In Example 1, pinning was performed when the upper surface of the slurry reached a position 24 mm lower than the foaming end height, and the restraint of the reinforcing bar 11 in the vertical direction was released during the swinging period of the mold 10. At this time, the penetration value was 220 mm, which was 61% of the penetration value at the end of foaming. In the longitudinal section 1a of the completed ALC panel 1, as shown in FIG. 1 (e), the foamed nest 4 was within a length of 5 mm or less. As for the cross section, as shown in Table 5, the foaming nest did not appear at any cover height in all three panels.

  In Example 1, since the pin return was performed at a timing later than that of Comparative Example 6, even if the slurry was liquefied in the vicinity of the uppermost rebar 3, the coagulation progressed lower than that to maintain the rebar as the whole slurry. I was able to strengthen my power. As a result, even during the swinging period of the mold 10, the reinforcing bar 11 is released from the mold 10 while being held in place, and the uppermost reinforcing bar 3 is raised following the volume expansion of the slurry, The formation of the foam nest 4 could be suppressed. When Example 1 and Comparative Example 6 are compared, the timing of pin return is after the upper surface of the slurry reaches a position 30 mm lower than the foaming end height, or the slurry viscosity is 55% of the viscosity at the end of foaming (penetration value 200 mm). It is desirable to be after reaching ().

  The rise of the uppermost reinforcing bar 3 in Example 1 will be described in detail. When the pin is turned back from the restraining position in FIG. 5A to the release position in FIG. 5B, the entire reinforcing reinforcing bar 11 expands the volume of the slurry. , And increased by 3 to 4 mm when measured at the location of the lower connecting bar 14. In addition to this rise, the portion of the uppermost reinforcing bar 3 between the spans of the secondary bars 13 bends upward as shown by the change from the two-dot chain line to the solid line in FIG. 5B, and the amount of deflection is It was 3-4 mm. Therefore, the uppermost reinforcing bar 3 was raised by 3 to 4 mm at the connection portion with the auxiliary muscle 13 and was raised by 6 to 8 mm in total at the portion between the spans of the auxiliary muscle 13.

<Example 2>
In Example 2, the timing of the pin return is further delayed, and when the upper surface of the slurry reaches a position 10 mm lower than the foaming end height, that is, a position where the swing of the mold 10 is finished, the reinforcing reinforcing bar 11 with respect to the mold 10 is The restriction on the vertical position was released. At this time, the penetration value was 248 mm, which was 69% of the penetration value at the end of foaming. In the longitudinal section of the completed panel, the foamed nest was within a length of 5 mm or less, as in Example 1. As for the cross section, as shown in Table 6, the foaming nest did not appear at any cover height in all three sheets.

  In Example 2, since the pin return timing was made coincident with the swing end timing, an operation for suppressing the foaming nest could be performed at the same time. For this reason, when the swing of the mold 10 and the rotation of the rod pin 15 are automatically operated, the manufacturing process of the ALC panel can be easily managed. Other effects are the same as those of the first embodiment.

<Example 3>
In Example 3, after the swing of the mold 10 was finished, when the upper surface of the slurry reached a position 4 mm lower than the foaming end height, the pin was turned back. At this time, the penetration value was 285 mm, which was 79% of the penetration value at the end of foaming. In the longitudinal section of the completed panel, the foamed nest was contained within a length of 5 mm or less. As for the cross section, as shown in Table 7, the foaming nest did not appear at any cover height in all three sheets.

  In Example 3, it was confirmed that the pin return was effective even at the timing after the end of the swinging. In particular, after the end of the swinging, the mold frame 10 was stationary, so that the position of the entire reinforcing steel bar 11 did not shift. Further, the entire reinforcing reinforcing bar 11 was firmly held by the high-viscosity slurry, and only the uppermost reinforcing bar was allowed to follow the final foaming of the slurry, thereby suppressing the foaming nest in a timely manner.

<Example 4>
In Example 4, after the end of rocking, when the upper surface of the slurry reached a position 2 mm lower than the foaming end height, the pin was turned back. At this time, the penetration value was 303 mm, which was 84% of the penetration value at the end of foaming. In the vertical section 1a of the completed panel, a gap 4a of about 10 mm appeared on the upper side of the uppermost reinforcing bar 3, as shown in FIG. Regarding the cross section, as shown in Table 8, foamed nests having a length of 2, 3 mm were scattered at a cover height of 10 mm of the three panels 1, 2, 3.

  According to Example 4, it was confirmed that the effect of suppressing the foaming nest due to the pinning was reduced just before the end of foaming. Since the slurry immediately before the end of foaming firmly holds the entire reinforcing bar 11, even when the vertical position of the reinforcing bar 11 is released, the uppermost reinforcing bar 3 cannot follow the volume expansion of the slurry. From this, the timing of the pin return is before the upper surface of the slurry reaches a position 2 mm lower than the foaming end height, or before the slurry viscosity reaches 84% of the viscosity at the end of foaming (penetration value 303 mm). This is desirable.

<Reference Example 5>
In Reference Example 5, pinning was performed at the time when foaming of the raw material slurry was completed (in FIG. 9, when about 40 minutes had elapsed from the start of foaming). The penetration value at this time was 360 mm (100%). In the longitudinal section 1a of the completed panel, as shown in FIG. 10A, the foamed nest 4 of about 10 mm to 25 mm appeared on the upper side of the uppermost reinforcing bar 3 as in Reference Example 2. Regarding the cross section, as shown in Table 9, 5 to 7 mm foamed nests appeared at a cover height of 10 mm, and 2,3 mm foamed nests were scattered at a cover height of 20 mm as in Reference Example 2.

  In comparison with Reference Example 5, it was possible to reconfirm the foaming nest suppression effect due to pinning in Examples 1 to 4. In addition, the following Table 10 shows the result of comprehensively evaluating the pin return timing of Examples 1 to 4, Reference Example 5 and Comparative Example 6.

The present invention is not limited to the above-described embodiments, and can be embodied with appropriate modifications without departing from the spirit of the invention, as exemplified below.
(1) The means for constraining the reinforcing reinforcing bar 11 to the mold 10 in the vertical position and the horizontal position is not limited to the rod pin 15 shown in FIG. 5, and the vertical position and horizontal position provided on the bottom surface or side surface of the mold 10. It is also possible to use a restraining member for the directional position.
(2) For measuring the viscosity of the slurry, a capillary viscometer or the like can be used instead of the scale 21 shown in FIG. You may measure the viscosity of the several places of a raw material slurry using a some viscometer.
(3) The period during which the mold 10 is swung is not limited to the period of the reference example and the example, and the foaming end height is increased after the upper surface of the slurry exceeds the uppermost reinforcing bar 3 corresponding to the blending of the raw slurry 2. It can be set to an arbitrary period until reaching this.
(4) A rotary table that reciprocally rotates can be used as the swinging device of the mold 10.

It is a schematic diagram explaining the production | generation mechanism of the foaming nest in an ALC panel. It is sectional drawing of the formwork which shows the outline | summary of the panel manufacturing method by this invention. It is a perspective view which shows the formwork and ALC panel which are used for the Example of this invention. It is a longitudinal cross-sectional view of the formwork in which the reinforcing bar was set inside. It is a perspective view which shows the rod pin which restrains an up-down direction position and a horizontal direction position to a reinforcement frame with a reinforcement frame. 6 is a graph showing foaming height and strength of a raw material slurry in Comparative Example 1. It is a longitudinal cross-sectional view of a formwork which shows the method of measuring the tension of a slurry. It is a perspective view of the ALC panel which evaluates the method of the comparative example 1. 4 is a graph showing foaming height and strength of a raw material slurry in Reference Example 1. It is a perspective view of the ALC panel which evaluates the method of the reference example 1. FIG. It is a graph which shows the foaming height change of the slurry which evaluates the method of the reference example 1. FIG. It is a graph which shows the toughness change of the slurry which evaluates the method of the reference example 1. FIG. It is a front view of the formwork which shows the method of the reference example 2. 10 is a graph for evaluating the method of Reference Example 3. It is a longitudinal cross-sectional view of the panel which shows the method of the reference example 4. It is a longitudinal cross-sectional view of the formwork and panel which show the method of the comparative example 2. It is a longitudinal cross-sectional view of the formwork and panel which show the method of the comparative example 3. It is a longitudinal cross-sectional view of the formwork and panel which show the method of the comparative example 4. It is a longitudinal cross-sectional view of the formwork and panel which show the method of the comparative example 5. It is an elevation which shows the timing of a pin return in the method of Examples 1-4.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ALC panel 2 Raw material slurry 3 Top rebar 4 Foaming nest 10 Form 11 Reinforcement rebar 15 Rod pin

Claims (4)

  In a swing period including at least a partial period after the upper surface of the raw material slurry exceeds the uppermost reinforcing bar of the reinforcing steel bar, the raw material slurry is foamed in the mold in which the reinforcing steel bar is constrained in the vertical position and the horizontal position. In addition to swinging the formwork and delaying the setting of the raw material slurry by the swinging, the restraint of the vertical position of the reinforcing reinforcing bar is released at the end of foaming of the raw material slurry, and the uppermost reinforcing bar is used for the volume expansion of the raw material slurry. A method for manufacturing a lightweight cellular concrete panel, characterized by suppressing the formation of a foaming nest on the upper side of the uppermost reinforcing bar by following and raising.   2. The lightweight bubble according to claim 1, wherein the partial period is a period in a range of 30 mm or more selected from an optimal period from when the upper surface of the raw material slurry exceeds 20 mm from the uppermost reinforcing bar to reach a position 10 mm lower than a foaming end height. A method for producing a concrete panel.   3. The method for producing a lightweight cellular concrete panel according to claim 1, wherein the timing of releasing the restraint of the vertical position of the reinforcing reinforcing bar is when the upper surface of the raw material slurry reaches a position 2 mm to 30 mm lower than the foaming end height.   The lightweight cellular concrete panel production according to claim 1 or 2, wherein the timing of releasing the restraint of the vertical position of the reinforcing reinforcing bar is when the viscosity of the raw slurry reaches 55% to 84% of the viscosity at the end of foaming. Method.

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