JP6537754B1 - Precast residual formwork panel for suppressing salt damage and frost damage of precast residual formwork panel, and manufacturing method of precast residual formwork panel - Google Patents

Abstract

The present invention provides a manufacturing method of a precast residual formwork panel capable of reliably suppressing salt damage and freezing damage.
A method of manufacturing a precast residual formwork panel, according to the present invention, excess water containing calcium hydroxide eluted from cement composition C fills capillary voids 9A and the like of the panel body 2 and the entire back surface 2a of the panel body 2 Covering with excess water containing calcium hydroxide to form the panel body 2, covering step of covering the entire back surface 2 a of the panel body 2 with the covering material 30, and curing step for curing the cement composition C Covering the entire back surface 2a of the panel body 2 with the covering material 30 prevents the formation of the water permeable fine powder layer L of calcium carbonate on the back surface 2a, and in the curing step, calcium hydroxide and cement composition The silica in C chemically reacts, and a waterproof layer 4 containing calcium silicate hydrate insoluble in water is formed on the entire area of the back surface 2 a, and capillary voids 9 and the like are formed by the waterproof layer 4. A configuration is.
[Selected figure] Figure 1

Description

  The present invention relates to a method for manufacturing a precast residual mold panel capable of suppressing salt damage and frost damage of a precast residual mold panel, and a precast residual mold panel.

As a construction method which coats a concrete wall surface, a remaining cast form construction method is known in which a precast residual mold panel is erected and concrete is cast on the back surface of the precast residual mold panel.
In the conventional residual mold construction method, as shown in FIG. 8A, a precast residual mold panel 101 provided with a connected fitting 103 on its back surface is used. The connected metal fitting 103 protrudes from the back surface of the precast residual formwork panel 101 and is exposed. In addition, on the back surface of the precast residual mold panel 101, a large amount of water permeable fine powder layer L containing calcium carbonate is present. The permeable fine powder layer L is produced by the reaction of calcium hydroxide and carbon dioxide in the open air in the process of manufacturing the precast residual mold panel.

  As shown in FIGS. 8 (a) and 8 (b), the conventional method for constructing a residual mold forms the precast residual mold panel 101 in the width direction X and the height direction on the front surface of the wooden mold (control panel) 113. After connecting to the connected metal fitting 103 and the wooden form 113 via the steel connecting metal (separator) 111 by stacking on Y and constructing the residual form 110, the back surface of the precast residual form panel 101 and A concrete 112 is placed between the wooden form 113 and hardened. During hardening, the concrete 112 shrinks, causing a crack displacement, and the concrete 112 generates a crack C2. When the crack C2 is generated, a tearing force is generated in the width direction X with respect to the precast residual mold panel 101, so that the crack C1 is generated in the precast residual mold panel 101. If the crack C1 is generated on the surface of the precast residual formwork panel 101, in addition to the objectionally undesirable, the long-term durability of the precast residual formwork panel 101 may be lowered. Specifically, as shown in FIG. 9, a plurality of cracks occur on the surface of the precast residual formwork panel. In addition, when such a crack occurs, the rainwater and the sewage from the concrete 112 side leak through the crack to the surface of the precast remaining formwork panel and contaminate the surface of the precast remaining formwork panel.

  The cracking is caused by the evaporation of water contained in the raw material of the concrete and the contraction of the concrete. The allowable range of cracks occurring in the structure is defined by the Japanese Industrial Standards and the ACI Committee as the “allowable crack width” (Non-Patent Document 1). The allowable crack width is about 0.05 to 0.40 mm, depending on the type of the structure and the surrounding environment of the structure.

  Cracks in concrete are divided into self-strain cracks caused by concrete's specific properties such as concrete aggregate, drying shrinkage, temperature and so on, and structural cracks caused by receiving load due to the weight and seismic force etc. of a building. The self-strained cracks are mainly classified into drying shrinkage cracks, sink cracks, temperature cracks, and freeze-thaw cracks. Among them, drying shrinkage cracks are known to be the most frequent among concrete cracks.

  Drying shrinkage cracking is, for example, a crack that occurs when concrete is subjected to a tensile force when it is restrained so as not to cause shrinkage of concrete such as a wall, and this tensile force is generated when the tensile strength of concrete is exceeded. is there. And this drying shrinkage crack is easy to occur when a structure with a large area or an end is restrained by a structure with high rigidity. In order to prevent this drying shrinkage crack, for example, a method of reducing the moisture content of concrete or mixing an expansive agent corresponding to the shrinkage amount into concrete is performed (for example, Patent Document 1).

  In the method of reducing the water content of the cement material or mixing the expansive agent corresponding to the contraction amount into the cement material as in Patent Document 1, in addition to the cost of mixing the expansive agent, In addition to the fact that the fluidity of the concrete is deteriorated and the concrete can not be appropriately placed in a complicated gap (space) in order to reduce the amount of water, there is also a possibility that a desired strength can not be obtained after hardening. In addition, when cracks occur up to the surface of the precast residual form panel, powder is applied to the cracked portions so as not to impair the appearance, and the crack is made to be made. However, in addition to the problem that the operation time and cost for applying the powder occur, there is a problem that the powder peels off from the remaining mold and the crack is exposed again when the time passes.

  In order to solve the said problem, the inventor has proposed the crack suppression method of the precast residual formwork panel (patent document 2). The crack control method of the precast residual formwork panel of patent document 2 is a precast residual type in which the connected metal fitting covered with the elastic resin cover material in the range of at least 10 mm from the back surface of the panel body of the precast residual formwork panel It is provided at a predetermined position on the back of the frame panel main body, and after the connected metal fittings and the steel connection metal fittings (separators) are connected to construct the remaining mold, concrete is poured on the back of the precast remaining mold panel. It includes a concrete placing step to be set up and a concrete curing step to set the concrete after placing the concrete. In the method for preventing cracking of the precast residual formwork panel, the portion covered with the elastic resin cover material of the connected metal fitting is not solidified by the concrete, and the crack displacement caused by the contraction of the concrete in the concrete hardening step is an elastic resin. By the elastic displacement follow-up function of the cover material and the elastic displacement follow-up function of the connected metal fittings, almost no transmission to the panel body causes cracks in the precast residual formwork panel and prevents deterioration after construction .

JP, 2017-105670, A Patent No. 6278378

Cracking measures (design and construction) guidelines for reinforced concrete structures, commentary 2nd edition 9th edition, Architectural Institute of Japan, March 1, 2000, p. 30-33

  The deterioration factors of the precast residual formwork panel include salt damage and frost damage as well as cracking caused by drying shrinkage due to rapid evaporation of the moisture of the poured raw concrete. The precast residual formwork panel main body is generally made of concrete, and a reinforcing bar as a reinforcing material is incorporated inside. For example, when salt water eluted from a snow melting agent intrudes into the precast residual formwork panel main body, it causes salt damage, and as shown in FIGS. 10 (a) and 10 (b), the progress of breakage of concrete and corrosion of reinforcing bars And the durability of the concrete decreases. In cold regions, in particular, freezing and thawing of water that has invaded the inside of the precast residual formwork panel body is repeated to cause freezing damage. If such salt damage or freezing damage occurs, cracking, deformation, peeling may occur, the durability of the precast residual form panel may decrease, or the appearance of the residual form may be impaired due to the whitening phenomenon. There is a possibility that the remaining mold can not be maintained in a desired state for a long time.

  In addition, when the water-permeable fine powder layer L is formed on the back surface of the precast residual formwork panel main body, it contains the contaminants generated from the cement-based solid material placed through the water-permeable fine powder layer L. The excess water exudes to the front surface from the back of the precast residual formwork panel, or leaks out from the joint between adjacent precast residual formwork panel main bodies, whereby the precast residual formwork panel main body Surface is contaminated (Figure 10). Thus, if the surface of the precast residual mold is contaminated, the appearance of the residual mold after construction is significantly impaired.

  An object of the present invention is to provide a precast residual formwork panel capable of reliably suppressing salt damage and frost damage of a precast residual formwork panel and having high durability, and a method of manufacturing the precast residual formwork panel. .

  The manufacturing method of the precast residual formwork panel according to the present invention is a method of manufacturing a precast residual formwork panel in which a connected metal fitting is embedded in the back surface of the panel main body, and the back surface of the panel main body faces upward and is horizontal. The mixture of cement composition and mixing water that composes mortar or concrete is put into a molding form designed to secure the excess, and surplus water containing calcium hydroxide eluted from the cement composition in mixing water Water is pushed up to the back side of the panel body, so that excess water intervenes so as to fill the capillary air gap formed inside the panel body and the air gap formed between the embedded portion of the connected fitting and the panel body. And covering the entire back surface of the panel body with the excess water containing calcium hydroxide to form the panel body, and after the forming step, covering the entire back surface of the panel body By covering the entire back surface of the panel body with a covering material, including a covering step of covering with a covering material and a curing step of curing the cement composition after the covering step, carbon dioxide and calcium hydroxide in the open air can be obtained. A chemical reaction is performed to prevent the formation of a permeable fine powder layer of calcium carbonate on the back of the panel body, and in the curing step, the calcium hydroxide eluted in the mixing water chemically reacts with the silica in the cement composition A waterproof layer containing water-insoluble calcium silicate hydrate is formed on the entire back of the panel body, and the capillary void and the void formed between the embedded portion of the connected fitting and the panel body are waterproof It is characterized by being blocked by a layer.

  In the precast residual formwork panel according to the present invention, the connected metal fitting is embedded in the back surface of the panel main body, and a waterproof layer containing calcium silicate hydrate is formed over the entire back surface of the panel main body. In addition, a capillary void existing inside the panel body and a void formed between the embedded portion of the connected fitting and the panel body are closed by the waterproof layer.

  The manufacturing method of the precast residual formwork panel according to the present invention includes a covering step of covering the entire back of the panel body with a covering material after the forming step. By covering the entire back of the panel body with the covering material, carbon dioxide in the outside air chemically reacts with calcium hydroxide eluted from the cement composition, and a permeable fine powder layer of calcium carbonate is formed on the back of the panel body. It can be prevented from being formed. By preventing the formation of the permeable fine powder layer, the calcium hydroxide eluted from the cement composition chemically reacts with the silica in the cement composition to form a waterproof layer containing calcium silicate hydrate which is insoluble in water. Are suitably formed on the back of the panel body. Furthermore, the capillary air gap and the air gap formed between the embedded portion of the connected fitting and the panel body are closed by the waterproof layer. As a result, excess water containing contaminants generated from the cement-based cement that has been cast out penetrates from the back surface of the precast residual formwork panel to the front surface, and the adjacent precast residual formwork panel main bodies Can be prevented from leaking out from the joint portion, and contamination of the surface of the precast residual formwork panel main body can be avoided.

The precast residual mold panel manufactured by the method for manufacturing a precast residual mold panel according to the present invention includes the entire back surface of the panel main body, the capillary gap of the panel main body, the embedded portion of the connected fitting and the panel main body Since the void formed between the two layers is completely blocked by the waterproof layer containing calcium silicate hydrate which is insoluble in water, the rainwater which has invaded the hardened concrete side and the salt water eluted from the snow melting agent are Intrusion inside the panel body is also suppressed.
Therefore, it is possible to suppress frost damage, salt damage and whitening phenomenon that occur to the panel body, and it is possible to avoid contamination, deterioration, breakage and deformation of the panel body.

It is a figure showing a precast remaining formwork panel concerning an embodiment of the present invention. (A) Cross section, (b) Rear view It is a figure for demonstrating the manufacturing process of the precast residual formwork panel which concerns on embodiment of this invention. (A) Forming step, (b) Coating step, (c) Curing step It is an enlarged view of the to-be-connected part after the coating process of the manufacturing method of the precast residual formwork panel which concerns on embodiment of this invention. It is a figure which shows the residual formwork constructed | assembled using the precast residual formwork panel which concerns on embodiment of this invention. (A) Cross section, (b) front view It is a rear view of a residual formwork constructed using a precast residual formwork panel according to an embodiment of the present invention. It is sectional drawing of the residual formwork for demonstrating the exposure of the rain water in the precast residual formwork panel constructed by the construction method of the conventional residual formwork, and a waste water. It is sectional drawing of the residual formwork constructed using the precast residual formwork panel which concerns on embodiment of this invention. It is a figure for demonstrating the process which a crack produces in the built remaining mold with the construction method of the conventional remaining mold. (A) Cross section, (b) front view It is a photograph which shows a mode that the crack arose in the precast residual formwork panel of the residual formwork constructed | assembled by the construction method of the conventional residual formwork. It is a photograph which shows the appearance of the surface contamination and damage which arose by frost damage and salt damage of the precast residual formwork panel of the residual formwork constructed | assembled by the construction method of the conventional residual formwork.

The construction method of the residual mold according to the present embodiment (hereinafter referred to as "construction method") is to construct a residual mold by using a precast residual mold panel.
Hereinafter, a construction method according to the present embodiment, a precast residual mold panel used for the construction method, and a method of manufacturing the precast residual mold panel will be described with reference to FIGS. 1 to 7. In the drawings, the lateral direction of the precast residual mold is referred to as width direction X, the vertical direction as height direction Y, and the thickness direction as longitudinal direction Z.

  In the construction method according to the present embodiment, the precast residual mold panel 1 shown in FIG. 1 is used. As shown in FIG. 1A, the precast residual formwork panel 1 is a predetermined position of the precast residual formwork panel main body 2 (hereinafter also referred to as the panel main body 2) and the back surface 2a of the panel main body 2. And a waterproof layer 4 formed on the back surface 2a of the panel main body 2 and the like.

[Panel body 2]
The panel body 2 has a rectangular shape as shown in FIGS. 1A and 1B, and the panel body 2 is, for example, 300 mm high and 900 mm wide. And in the back surface 2a of the panel main body 2, the to-be-connected metal fitting 3 is provided in the width direction X and the height direction Y two each. The connected fitting 3 is provided so as to protrude from the back surface 2 a of the panel body 2. Further, in the width direction X and the height direction Y inside the panel body 2, a plurality of reinforcing bars 5 are provided in order to ensure the strength of the panel body 2.

[Attached fitting 3]
The connected fitting 3 includes a hook portion 6 and a buried portion 7 connected to both ends of the hook portion 6. The embedded portion 7 is embedded in the panel body 2 so that the hook portion 6 protrudes from the back surface 2 a of the panel body 2 and is provided on the panel body 2. A metal-made material can be used as the connected metal fitting 3, and a material excellent in corrosion resistance is preferably used. For example, a stainless steel material (SUS304) can be used.

[Waterproof layer 4]
The waterproof layer 4 is composed of a layer containing calcium silicate hydrate which is insoluble in water. The waterproof layer 4 is formed on the entire area of the back surface 2 a of the panel main body 2 and in the air gap 9 B formed between the capillary air gap 9 A and the embedded portion 7 of the connected fitting 3 and the panel main body 2.

  The waterproof layer 4 contains calcium aluminate hydrate as well as calcium silicate hydrate. The calcium silicate hydrate contained in the waterproof layer 4 is produced by the chemical reaction of the silica in the cement composition C, which is the mortar or concrete constituting the panel body 2, with calcium hydroxide. Moreover, calcium aluminate hydrate is produced | generated because aluminum oxide of the cement composition C and calcium hydroxide react.

  Next, a method of manufacturing the precast residual mold panel 1 will be described.

[Molding process]
In the embedding step, as shown in FIG. 2, the panel body 2 is molded using a molding form 22. The molding form 22 is designed such that the back surface 2a of the panel body 2 is maintained upward and horizontally. The upper side of the molding form 22 is the back surface 2 a side of the panel body 2.
Specifically, as shown in FIG. 2A, a mixture of kneading water and cement composition C is introduced into the inside of a forming frame 22 installed on a table 21 provided with a vibrating device 20, The vibration device 20 vibrates the cement composition C. Then, excess water containing calcium hydroxide eluted from cement composition C is pushed up to the back surface 2 a side of the panel body 2 in the mixing water. The excess water intervenes so as to fill the capillary air gap 9 formed inside the panel body 2 and the air gap 9 B formed between the embedded portion 7 of the connected fitting 3 and the panel body 2. The entire back of the is covered with excess water containing calcium hydroxide.

[Coating process]
After the molding process, the entire back surface 2 a of the panel body 2 is covered with the covering material 30. The covering material may cover the excess water pushed up on the back surface 2a side of the panel main body 2 so long as the excess water can be prevented from coming into contact with the open air. For example, a covering material or a wrap forming an oil film -Shaped coverings can be used. In the present embodiment, a liquid covering material 30 is used.
Specifically, as shown in FIG. 2 (b), the covering device 30 is sprayed by the spraying device 23 from the upper side of the molding form 22 that is on the back surface 2 a side of the panel main body 2. Then, as shown in FIG. 3, the entire back surface 2 a side is covered with a covering material 30, and the covering material 30 blocks excess water containing calcium hydroxide forming the waterproof layer 4 from the outside air.

[Burying process]
After the covering step, as shown in FIG. 2C, the connected metal fitting 3 attached to the reinforcing bar 5 is embedded in the cement composition C poured into the molding form 22. Specifically, the connection portion between the hook portion 6 and the embedded portion 7 and the embedded portion 7 are pushed to a predetermined position in the cement composition C and embedded.
The embedding step can also be performed before the covering step. In this case, after the connected metal fitting 3 is embedded, the entire back surface 2 a of the panel body 2 is covered with a covering material.

[Care process]
In the curing step, calcium hydroxide eluted when the cement in the cement composition C hardens reacts with the silica contained in the cement composition C to form calcium silicate hydrate. Then, the entire back surface 2a of the panel body 2, the capillary air gaps 9A and the air gaps 9B are closed by the waterproof layer 4 containing calcium silicate hydrate.
The covering material 30 is hardly left on the back surface 2 a of the panel body 2 because it is washed away or evaporated. The covering material 30 may be left depending on the application.

  In the forming step and the curing step, the excess water is pushed up to the back side of the panel body 2 to be stored in the entire back surface 2 a of the panel body 2. Then, the excess water covers the back surface 2 a of the panel main body 2 and the capillary air gap 9 A formed inside the panel main body 2 and the air gap 9 B formed between the embedded portion 7 of the connected fitting 3 and the panel main body 2 Intervene to fill.

  Next, a construction method using the precast residual mold panel 1 manufactured by the above-described manufacturing method will be described. The cement-based cement used in the method of construction of the remaining form can be used if it contains water and solidifies with time, and concrete, mortar, foam mortar, etc. can be used, for example. . In the present embodiment, an example in which concrete 12 is used as a cement-based binder will be described.

  In the construction method according to the present embodiment, as shown in FIG. 4 (b), the precast residual formwork panel 1 is stacked to construct a residual formwork 10. In the precast residual mold panel 1, the waterproof layer 4 is formed on the entire back surface 2a of the panel body 2, the capillary air gaps 9A, and the air gaps 9B. When constructing the residual formwork, as shown in FIG. 4 (a), the wooden connection metal fitting (separator) 11 connected to the connected metal fitting 3 and the wooden formwork (control panel) 13 is used to connect the wood The precast residual formwork panel 1 is fixed to the front of the formwork 13.

  As shown in FIG. 5, the end portions of the waterproof layer 4 are made of a sealing material, as shown in FIG. 5, by pasting the sealing material 14 on the joint portion 8 of the adjacent precast residual form panel 1 They are joined together by 14. By connecting the end portions of the waterproof layer 4, the entire area of the back surface 2 a of the precast remaining mold panel 1 is completely covered with the waterproof layer 4 and the sealing material 14. For the sealing material 14, for example, a silicon sealing material or a waterproof tape can be used.

  Next, a cement-based solid material placing step is performed. Concretely, concrete 12 is placed between the precast residual formwork panel 1 and the wooden formwork 13 (FIG. 4 (a)). Concrete 12 is cast to be in contact with the waterproof layer 4 formed on the back surface 2 a of the panel body 2.

  After placing the concrete 12, the concrete 12 is hardened (cement-based solid material hardening step). At this time, since the waterproof layer 4 is formed in the capillary air gaps 9A and the air gaps 9B, the moisture of the concrete 12 is prevented from entering the inside of the panel main body 2 from the capillary air gaps 9A and the air gaps 9B. Then, the release and evaporation of the moisture of the concrete 12 are suppressed, and the drying shrinkage crack of the concrete 12 is suppressed.

  Next, the effect of the manufacturing method of the precast residual formwork panel 1 which concerns on this embodiment, and the precast residual formwork will be described.

  Conventionally, as shown in FIG. 6, using a panel body 102 having a water-permeable fine powder layer L containing calcium carbonate formed on the back surface, concrete 112 is cast on the back surface of the panel body 102, and the remaining mold 100 is It was constructing. Therefore, rainwater passing through the water-permeable fine powder layer L containing calcium carbonate, dirty water generated from the concrete 112 side, etc. leaks to the outside of the panel main body 102 through the capillary air gap 109. Furthermore, rainwater, dirty water, etc. flow out to the outside of the panel main body 102 through the joint 108. Then, the surface of the precast residual formwork panel 101 is contaminated by frost damage, salt damage, and whitening phenomenon. Moreover, in the concrete hardening process of the construction method of the conventional residual formwork 100, the moisture of the concrete 112 is released from the capillary air gap 109 to the outside of the panel main body 102 and evaporates to cause a dry crack, which results in concrete Cracks have occurred in the panel 112 and the panel body 102.

In the precast residual formwork panel 1 according to the present embodiment, the waterproof layer 4 is formed on the entire back surface 2a of the panel main body 2, and as shown in FIG. 7, the capillary air gap 9A and the embedded portion 7 of the connected fitting 3 A void 9B (omitted from the drawing) formed between the panel body 2 and the panel body 2 is completely blocked by the waterproof layer 4 containing a water-insoluble calcium compound. Therefore, it is suppressed that the rainwater which penetrate | invaded into the hardened | cured concrete 12 side and the salt water eluted from snow melting agents penetrate | invade into capillary space | gap 9A (inside of the panel main body 2) of the panel main body 2. Furthermore, by joining the end portions of the waterproof layer 4 of the adjacent panel main bodies 2 with the sealing material 14, the joint portion 8 and the concrete 12 side are blocked, and therefore rainwater or snow melting that has invaded the hardened concrete 12 side. The salt water eluted from the agent can be prevented from leaking out from the gap of the joint portion 8 to the surface of the precast residual mold panel 1 (outside of the panel main body 2) for a long time.
Therefore, it is possible to suppress frost damage, salt damage and whitening phenomenon that occur to the panel main body 2, and contamination, deterioration, breakage, deformation of the panel main body 2, and reinforcing bars 5 as a reinforcing material of the panel main body 2 Corrosion can be avoided.

The manufacturing method of the precast residual formwork panel which concerns on this embodiment covers the back surface 2a whole region of the panel main body 2 with the covering material 30 before a curing process. By covering with the covering material 30, the contact between the excess air including the pushed up calcium hydroxide and the outside air on the entire back surface 2a of the panel main body 2 is blocked. Then, the carbon dioxide in the outside air and the calcium hydroxide in the surplus water react chemically, and the formation of the water-permeable fine powder layer of calcium carbonate on the back surface of the panel body is suppressed.
Therefore, calcium hydroxide in the surplus water chemically reacts with silica (silicon dioxide) in cement composition C to form calcium silicate hydrate, and water-insoluble calcium silicate hydrate is formed over the entire back surface 2a. The waterproof layer 4 including the object can be formed with certainty.

  And, by blocking the contact between the excess water containing calcium hydroxide and the outside air by the covering material 30, the water component of the excess water can be prevented from evaporating, and the environment is high or the air temperature is high. Even in the environment, the precast residual formwork panel 1 can be manufactured appropriately.

In addition, the precast residual formwork panel 1 used in the present embodiment is provided with the waterproof layer 4 containing calcium silicate hydrate insoluble in water, and the capillary air gaps 9A and the air gaps 9B of the panel main body 2 are blocked. Because of this, in the cement-based solid material hardening step, the moisture of the raw concrete 12 cast from the capillary air gap 9A is rapidly released and suppressed from evaporating. As a result, the concrete 12 is gradually consolidated, and cracking is less likely to occur, and cracking of the panel body 2 is suppressed after the remaining mold 10 is constructed.
As described above, the effect of making the crack less likely to occur due to the concrete 12 gradually solidifying is effective when constructing the residual formwork in summer or when constructing the residual formwork 10 in a sunny position. It is.

  As described above, the precast residual formwork panel 1 manufactured by the method for manufacturing the precast residual formwork panel according to the present embodiment can prevent deterioration due to salt damage and frost damage, and cracks may occur in the precast residual formwork panel 1 In addition, it is possible to prevent the surface of the precast residual mold panel 1 from being contaminated. Therefore, a construction method using the precast residual mold panel 1 manufactured by the method for manufacturing a precast residual mold panel according to the present embodiment is very useful and has high versatility. It is.

As mentioned above, although this embodiment was described, it is possible not only to deviate from the gist of the present invention, but to select the configuration described in the above embodiment or to appropriately change it to another configuration. . For example, when the waterproof layer 4 is formed on the entire area of the back surface 2a, the most remarkable effect is produced. However, even if it is not the entire area of the back surface 2a, the area where the waterproof layer 4 is provided is not limited as long as the desired effect occurs.
Moreover, in this embodiment, although the to-be-connected metal fitting 3 showed the thing of a hook shape to an example, if it can be made to connect with the connection metal fitting 11, it will not be limited to a hook shape.

  In the present embodiment, a liquid material is used as the covering material 30. However, for example, a covering material 30 in the form of a wrap can also be used. When using the wrap-like covering material 30, the covering material 30 is covered on the back surface 2a side of the panel main body 2 after the embedding step of the connected fitting 3 and the covering material 30 is removed after the curing step.

1 Precast residual formwork panel (panel)
2 Precast residual formwork panel main body (panel main body)
2a back (back)
Reference Signs List 3 connected fitting 4 waterproof layer 5 reinforcing bar 6 hook portion 7 embedded portion 8 joint portion 9A capillary air gap 9B air gap (air gap formed between the embedded portion 7 and the panel main body 2)
10 Residual form 11 Connection bracket (separator)
12 Concrete (Cement-based consolidated material)
13 Wooden formwork (control panel)
14 Sealing material 20 Vibration device 21 Base 22 Molding form 23 Spraying device 30 Coating material 100 Residual form 101 Precast residual form panel 102 Panel main body 103 Connected fitting 108 Joint part 109 Capillary void 110 Residual form 111 111 Connecting fitting (Separator)
112 concrete 113 wooden formwork (control panel)
114 Sealing material C Cement composition C1, C2 Cracked L Permeate fine powder layer X Width direction Y Height direction Z Front and back direction

Claims (1)

It is a manufacturing method of the precast residual formwork panel which manufactures the precast residual formwork panel by which the to-be-connected metal fitting was embedded at the back of a panel main body,
A mixture of a cement composition constituting mortar or concrete and kneading water is introduced into a molding form designed to ensure that the back surface of the panel body is upward and horizontal, and the cement is mixed with the cement water. The excess water containing calcium hydroxide eluted from the composition is pushed up to the back side of the panel body, so that the excess water is formed in a capillary void formed inside the panel body, and the embedded portion of the connected fitting. Forming the panel body by covering the entire back surface of the panel body with the excess water containing calcium hydroxide, so as to fill a gap formed between the panel body and the panel body;
A covering step of covering the entire back surface of the panel body with a covering material after the forming step;
Curing the cement composition after the coating step;
By covering the entire back surface of the panel body with the covering material, carbon dioxide in the outside air chemically reacts with the calcium hydroxide to form a water permeable fine powder layer of calcium carbonate on the back surface of the panel body. To prevent that
In the curing step, the calcium hydroxide eluted in the mixing water chemically reacts with the silica in the cement composition, and the waterproof layer containing calcium silicate hydrate insoluble in water is the entire back surface of the panel body. And the waterproof layer is used to close the capillary air gap and the air gap formed between the embedded portion of the connected fitting and the panel body.
A method of manufacturing a precast residual mold panel characterized in that.