JP2022020830A - Heat-insulating and moisture-retaining curing sheet for concrete - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable a concrete placing surface during curing to be kept constantly wet, and allow heat-insulating and moisture-retaining curing after concrete placing for improving the durability of concrete by causing the hydration reaction of the placed concrete sufficiently.

SOLUTION: In order to perform a heat-insulating and moisture-retaining curing of concrete placed, a heat-insulating and moisture-retaining curing sheet 1 for concrete which is used by being laid on a concrete placing surface 10 is provided with an uneven sheet member 2 having an uneven surface forming a predetermined space S on a side of the concrete placing surface 10 when the concrete placing surface 10 is laid, and the uneven sheet member 2 is water-impermeable and has at least one water supply port 3. The uneven surface side of the uneven sheet member 2 is connected with a nonwoven fabric, a woven fabric, or a braided fabric 5. The uneven surface side of the uneven sheet member 2 of the water supply port 3 is covered with the nonwoven fabric, the woven fabric, or the braided fabric 5.

SELECTED DRAWING: Figure 5

COPYRIGHT: (C)2022,JPO&INPIT

Description

The present invention relates to a heat-retaining / moisturizing curing sheet for concrete used by laying it on a concrete-casting surface in order to heat-retain / moisturize the placed concrete.

If the cast concrete dries rapidly before a sufficient hydration reaction is carried out, problems such as deterioration of its durability will occur. In addition, if the heat insulation of the concrete casting surface is not sufficient, cracks and the like are likely to occur. For this reason, after concrete is placed at a construction site such as construction work or civil engineering work, water is usually sprinkled on the concrete placement surface and covered with a curing sheet to prevent the concrete from drying rapidly and the surface temperature from dropping. is doing.

As such a curing sheet, Patent Document 1 discloses a concrete curing sheet in which a water-impermeable plastic sheet is joined to one side of a hydrophilic plastic resin non-woven fabric.

Japanese Unexamined Patent Publication No. 2014-237925

By the way, Patent Document 1 describes an example in which a watering hose provided with a large number of watering holes is arranged on one end side of a curing sheet and water is sprinkled into a non-woven fabric to cure concrete (Patent). Refer to paragraph [0026] of Document 1).

However, if water is sprinkled from one end side of the curing sheet as in Patent Document 1, if the curing sheet is laid on a horizontal surface, for example, when a concrete deck is constructed, the water is sprinkled. Most of them may stay on one end side of the curing sheet, and it is difficult to spread them evenly to the other end side of the curing sheet.

In order to improve the durability of the cast concrete, it is preferable to keep the concrete wet for as long as possible so that the hydration reaction is sufficient, especially when constructing a concrete deck. Since the number of curing days is short, it is important to properly perform initial curing. However, in the curing sheet of Patent Document 1, the concrete casting surface being cured is always kept wet after casting. It was not enough to properly keep the concrete warm and moisturized.

In the present invention, the above circumstances are taken into consideration, and it is possible to keep the concrete casting surface being cured in a wet state at all times, so that the hydration reaction of the cast concrete is sufficiently performed. The purpose of the present invention is to provide a heat-retaining / moisturizing curing sheet for concrete that can heat-retain / moisturize the concrete after casting so that the durability of the concrete can be improved.

The heat insulating / moisturizing curing sheet for concrete according to the present invention is a heat insulating / moisturizing curing sheet for concrete used by laying it on a concrete casting surface in order to heat / moisturize the cast concrete. A concavo-convex sheet-like member having an concavo-convex surface that forms a predetermined void on the concrete-casting surface side when laid on the concrete-casting surface is provided, and the concavo-convex sheet-like member is impermeable to water and at least one. It has two water supply ports, and a non-woven fabric, woven fabric, or knitted fabric is joined to the uneven surface side of the uneven sheet-shaped member, and the uneven surface side of the concave-convex sheet-shaped member of the water supply port is the non-woven fabric, woven fabric. It is configured to be covered with cloth or knitted cloth.

According to the present invention, it is possible to keep the concrete casting surface being cured in a wet state at all times, and the hydration reaction of the cast concrete is sufficiently performed to improve the durability of the concrete. The concrete after casting can be kept warm and moisturized so that it can be improved.

It is explanatory drawing which shows the outline of the heat insulation / moisture insulation sheet for concrete which concerns on the reference embodiment of this invention. It is explanatory drawing which shows an example of manufacturing the concave-convex sheet-like member. It is a BB end view of FIG. 1 (a). It is explanatory drawing which shows the outline of an example of the heat insulation | moisture retention curing method of concrete which concerns on a reference embodiment of this invention. It is explanatory drawing which shows the outline of the heat insulation / moisture insulation sheet for concrete which concerns on embodiment of this invention.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

[Reference Embodiment]
First, a reference embodiment of the present invention will be described.

The curing sheet 1 shown in FIG. 1 is used by laying it on the concrete placing surface 10 in order to heat-retain and moisturize the placed concrete. Further, when laid on the concrete placing surface 10, the uneven sheet-like member 2 having an uneven surface forming a predetermined gap S on the concrete placing surface 10 side is provided, and the uneven sheet-like member 2 is not present. It is water permeable and has at least one water supply port 3.

1 (a) is a plan view showing an outline of a heat-retaining / moisturizing curing sheet for concrete according to the present embodiment, and FIG. 1 (b) is an end view of AA of FIG. 1 (a). 1 (b) also shows a cross section of concrete including a casting surface 10 on which the curing sheet 1 is laid.

In the present embodiment, as shown in FIG. 1 (b), the concave-convex sheet-like member 2 has a cap film 21 on which a large number of protrusions 20 bulging in a hollow shape are formed, and a back that encloses air in the protrusions 20. A film 22 is included, and these are laminated by heat fusion. By providing the concave-convex sheet-like member 2 in which air is sealed in the protrusion 20, the curing sheet 1 can be provided with heat insulating properties.

In order to produce such a concavo-convex sheet-like member 2, for example, as shown in FIG. 2, first, a material resin in a molten state is flattened on the outer peripheral surface of a molding roll 100 provided with a large number of suction cavities 101. By continuously supplying the film from the die 121 in the form of a film, a large number of protrusions 20 that bulge into a hollow shape are vacuum-formed, and a cap film 21 in which the protrusions 20 are formed in a predetermined arrangement is formed. The arrangement of the protrusions 20 can be a grid arrangement, a staggered arrangement, or the like.

Each of the suction cavities 101 provided in the molding roll 100 is connected to a vacuum pump (not shown), and vacuum forming can be performed by vacuum suctioning the inside of the suction cavity 101. Further, the arrangement of the suction cavities 101 is appropriately designed according to the arrangement of the protrusions 20 to be formed on the cap film 21.

Then, while molding the cap film 21, the material resin in the molten state is continuously supplied in the form of a film from the flat die 122 to form the back film 22, and this is used on the opening side of the protrusion 20 formed on the cap film 21. It is crimped to and laminated by heat fusion. As a result, the concave-convex sheet-like member 2 in which air is sealed in the protrusion 20 can be manufactured.

In producing the concave-convex sheet-like member 2 in this way, the basis weight of the cap film 21 and the back film 22 is appropriately adjusted such as the discharge amount of the material resin continuously supplied from the flat dies 121 and 122 and the line speed. Therefore, the basis weight can be set to a predetermined amount according to the strength required for the concave-convex sheet-like member 2. Further, as the material resin, for example, a polyolefin-based resin such as polypropylene or polyethylene, or a thermoplastic resin such as a polyester-based resin such as polyethylene terephthalate can be used alone or in combination of two or more. The shape member 2 is not limited to these as long as it can be made impermeable to water.

In the present embodiment, the curing sheet 1 is laid so that the uneven surface side of the uneven sheet-like member 2 faces the concrete placing surface 10, and the placed concrete is heat-retaining and moisturized. At that time, the curing sheet 1 may be carried into the construction site in a rolled state and laid on the concrete placing surface 10 while being cut to an appropriate length, which is appropriate in advance. You may cut it to a suitable size. Further, the curing sheet 1 used at another construction site can be reused. When laying the curing sheet 1 on the concrete placing surface 10, a plurality of curing sheets 1 may be laid side by side according to the size of the concrete placing surface 10.

By laying the curing sheet 1 on the concrete casting surface 10, the moisture contained in the concrete being cured is suppressed from being dissipated due to evaporation, and the heat insulating effect of the uneven sheet-like member 2 in which air is sealed in the protrusion 20 is obtained. The concrete placing surface 10 can be kept warm to promote the hydration reaction of concrete.

Further, since the uneven sheet-shaped member 2 has the water supply port 3, water is additionally supplied from the water supply port 3 between the concrete casting surface 10 and the uneven sheet-shaped member 2 even after the curing sheet 1 is laid. can do. Moreover, the supplied water can be evenly distributed to the concrete placing surface 10 by using the void S formed on the concrete placing surface 10 side as a water passage, and the excess water that the concrete could not completely absorb at the time of water supply. Can be stored in the void S, so that the concrete placing surface 10 being cured can always be kept wet.

Normally, the curing sheet 1 is cut into a rectangular shape and laid. Therefore, in order to evenly distribute the supplied water to the concrete casting surface 10, the water supply port 3 is the intersection of the diagonal lines of the curing sheet 1 cut into a rectangular shape when laid on the concrete casting surface 10 or its own. Although it is preferably located in the vicinity, a plurality of water supply ports 3 may be provided in an appropriately set arrangement so that the supplied water can be evenly distributed on the concrete casting surface 10. Further, when the curing sheet 1 is laid on the concrete casting surface 10, the water supplied from the water supply port 3 is supplied from the peripheral edge of the curing sheet 1 by, for example, attaching the peripheral edge of the curing sheet 1 with a curing tape. It is preferable to prevent it from leaking out. Further, if water is supplied from the water supply port 3 and then the water supply port 3 is also covered with an adhesive tape or the like, if necessary, it is possible to prevent the water from escaping from the water supply port 3.

Further, the reason why air stays in the void S formed on the concrete placing surface 10 side and the water flow is hindered is that the water supplied from the supply port 3 is evenly distributed to the concrete placing surface 10. Is not preferable. For this reason, the concave-convex sheet-like member 2 preferably has an air vent portion 4.

The air bleeding portion 4 may be formed by drilling a through hole in the concave-convex sheet-shaped member 2, or may be formed by making a notch in the concave-convex sheet-shaped member 2. In the latter case, for example, by making an arc-shaped cut in the concave-convex sheet-shaped member 2 and making a cut 4c while leaving the connecting portion 4b in the concave-convex sheet-shaped member 2, the connecting portion 4b is used as a fulcrum. It is preferable that the valve body piece 4a that can be opened and closed is formed together with the air vent portion 4 (see FIG. 3). By doing so, it is possible to prevent the air from escaping from the air bleeding portion 4 while preventing the moisture from escaping from the air bleeding portion 4.
3 is an end view of BB of FIG. 1A, and FIG. 3 also shows a cross section of concrete including a casting surface 10 on which the curing sheet 1 is laid.

The position where the air vent portion 4 is formed is not particularly limited as long as it does not hinder the air that stays between the concrete placing surface 10 and the concave-convex sheet-like member 2. For example, when the curing sheet 1 is cut into a rectangular shape and laid, it can be formed on the four corner sides of the concave-convex sheet-like member 2.

In order to supply water from the water supply port 3, for example, the tip of a hose connected to a water supply source such as water supply can be inserted into the water supply port 3 so that water can flow from the hose. If the concrete casting surface 10 being cured can be kept wet at all times, a small amount of water may be continuously flowed from the hose, or a predetermined amount of water may be intermittently flowed. ..

When water is supplied in this way, the water supply port 3 may be bored in a size sufficient to insert the tip of the hose, but it is a triangular section formed by radially cutting the uneven sheet-like member 2. May be made to stand up to form the water supply port 3. In the latter case, the hose can be attached to the water supply port 3 by fixing the section along the peripheral surface of the hose with a hose band or the like. Further, a tubular connector to which a hose can be detachably connected can be attached to the water supply port 3.

Further, when there is no water supply source such as water supply nearby, a portable water storage tank 6 such as a plastic tank can be used, but in this case, the flow rate can be adjusted on the bottom side of the water storage tank 6. It is preferable to provide a water injection port 60. By doing so, the water injection port 60 is inserted into the water supply port 3, and the water storage tank 6 is simply placed on the curing sheet 1, and the concrete casting surface 10 and the uneven sheet-like member are formed from the water supply port 3. Water can be supplied between 2 and 2 (see FIG. 4). At this time, since the concave-convex sheet-like member 2 also functions as a cushioning material by the protrusion 20 in which air is sealed, the void S formed on the concrete placing surface 10 side is closed by the weight of the water storage tank 6. Water flow is not obstructed.

According to the present embodiment as described above, water can be additionally supplied from the water supply port 3 to the concrete placing surface 10, and the water supplied from the water supply port 3 is supplied to the gap S formed on the concrete placing surface 10 side. It is possible to keep the concrete casting surface 10 being cured always wet by storing it in the void S while spreading it evenly over the concrete casting surface 10 as a water passage. The concrete after casting can be kept warm and moisturized so that the hydration reaction of the concrete is sufficiently carried out and the durability of the concrete can be improved.

Further, when the concrete after casting is heat-retained and moisturized in this way, in the present embodiment, the curing sheet 1 is colored so that the concrete casting surface 10 is not exposed to direct sunlight. , Aluminum foil layer, etc. can be laminated. When coloring the curing sheet 1, for example, the heat retaining property can be enhanced by coloring the curing sheet 1 in a color that easily absorbs heat, and when performing heat insulating / moisturizing curing of concrete in winter or cold regions. Is preferable.

When the curing sheet 1 is laid on the concrete placing surface 10, the height of the protrusion 20 of the uneven sheet-like member 2 is formed so that a gap S having a sufficient width as a water passage is formed on the concrete placing surface 10. The height can be, for example, 3.5 to 10 mm, and the shape of the protrusion 20 can be a truncated cone.
Although an example of manufacturing the concave-convex sheet-shaped member 2 has been described with reference to FIG. 3, it goes without saying that the present invention is not limited to this.

[Embodiment]
Next, an embodiment of the present invention will be described.

In the present embodiment, the curing sheet 1 has a non-woven fabric, woven fabric, or knitted fabric 5 bonded to the uneven surface side of the concave-convex sheet-like member 2, and the concave-convex sheet-like member 2 of the water supply port 3 has the uneven surface side. It is closed with a non-woven fabric, woven cloth, or knitted cloth 5 (see FIG. 5 (b)). By doing so, the water supplied from the water supply port 3 spreads over the concrete casting surface 10 as a water passage through the void S formed on the concrete casting surface 10 side, and is made of non-woven fabric, woven cloth, or knitting. It is impregnated into the cloth 5 and stored between the uneven sheet-like member 2 and the concrete placing surface 10. Therefore, the concrete casting surface 10 being cured can be kept wet for a long period of time, and the number of times of water supply required can be reduced.

5 (a) is a plan view showing an outline of a heat-retaining / moisturizing curing sheet for concrete according to the present embodiment, and FIG. 5 (b) is an end view of BB of FIG. 5 (a). 5 (b) also shows a cross section of the concrete including the casting surface 10 on which the curing sheet 1 is laid.

In the present embodiment, the non-woven fabric, woven fabric, or knitted fabric 5 bonded to the uneven surface side of the concave-convex sheet-like member 2 can contain moisture-absorbing and heat-generating fibers.

As the moisture-absorbing / releasing heat-generating fiber, a fiber having a moisture-absorbing / releasing property and generating heat when absorbing moisture is used. As such a fiber, a fiber obtained by subjecting an acrylic nitrile fiber to a cross-linking treatment using a hydrazine-based compound and a hydrolysis treatment is preferable. For example, "Breath Thermo (registered trademark) manufactured by Mizuno Co., Ltd." ) ”, Commercial products such as“ EX (registered trademark) ”manufactured by Toyobo Co., Ltd. or improved products thereof can also be used.

By doing so, in addition to being able to impregnate the non-woven fabric, the woven fabric, or the knitted fabric 5 with the water supplied from the water supply port 3 and keep the concrete casting surface 10 being cured in a wet state for a long period of time. The heat-retaining property is further enhanced by the heat-absorbing and desorbing heat-generating fibers generated by the water impregnated in the non-woven fabric, the woven fabric, or the knitted fabric 5. As a result, it becomes possible to carry out heat insulation and moisturizing curing of concrete even in winter or cold regions.

Further, the non-woven fabric, the woven fabric, or the knitted fabric 5 bonded to the uneven surface side of the concave-convex sheet-like member 2 can contain a moisture-absorbing color-developing agent.

Examples of the hygroscopic color former include cobalt dichloride (which turns blue when dry and turns pale red when it absorbs moisture) and copper sulfate (which turns white when dry and turns blue when it absorbs moisture). Then, a compound having a different color between the anhydrous substance and the hydrate is used.

By doing so, the water supplied from the water supply port 3 is impregnated with the non-woven fabric, the woven cloth, or the knitted cloth 5, and the concrete casting surface 10 being cured can be kept wet for a long period of time. It is possible to easily confirm whether or not the non-woven fabric, the woven fabric, or the knitted fabric 5 water is impregnated, thereby determining the necessity of water supply.

Further, the non-woven fabric, the woven fabric, or the knitted fabric 5 bonded to the uneven surface side of the concave-convex sheet-like member 2 can contain a water-absorbent resin.

Examples of the water-absorbent resin include polyacrylic acid salt type, polysulfone salt type, maleic anhydride type, polyacrylamide type, polyvinyl alcohol type, polyethylene oxide type and other synthetic resin type, polyaspartic acid type and polyglutamate type. , Polyarginate-based, starch-based, cellulose-based and other natural substance-derived systems are known. Among these, those having the property of absorbing water to form a gel to retain water and gradually releasing water as the surroundings dry are preferable. For example, Nippon Shokubai Co., Ltd. Commercially available products such as "Acrihope (registered trademark)" or improved products thereof can also be used.

By doing so, the water supplied from the water supply port 3 is not only impregnated with the non-woven fabric, the woven fabric, or the knitted fabric 5, but also absorbed by the water-absorbent resin. More water can be stored between the casting surface 10 and the casting surface 10. Then, as the drying of the concrete progresses, the water absorbed by the water-absorbent resin is gradually released, so that the concrete placing surface 10 being cured can be maintained in a wet state for a longer period of time.

This embodiment is different from the reference embodiment in the above points, but is the same as the reference embodiment except for the above-mentioned points, and thus the duplicate description will be omitted.

Although the present invention has been described above with reference to preferred embodiments, it is needless to say that the present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the present invention. ..

INDUSTRIAL APPLICABILITY The present invention can be used as a technique for heat-retaining and moisturizing the placed concrete, and can be particularly preferably used when constructing a concrete deck or the like.

1 Curing sheet 10 Concrete casting surface 2 Concavo-convex sheet-like member 3 Water supply port 4 Air vent 4a Valve body piece 4b Connecting part 4c Notch 5 Non-woven fabric, woven cloth, or knitted cloth 6 Water storage tank 60 Water injection port S Void

Claims (1)

A heat-retaining / moisturizing sheet for concrete used by laying it on the concrete-casting surface in order to heat-retain / moisturize the placed concrete.
A concavo-convex sheet-like member having an concavo-convex surface that forms a predetermined gap on the concrete-casting surface side when laid on the concrete-casting surface is provided.
The uneven sheet-like member is impermeable and has at least one water supply port.
A non-woven fabric, a woven cloth, or a knitted fabric is joined to the uneven surface side of the uneven sheet-shaped member, and the uneven surface side of the uneven sheet-shaped member of the water supply port is closed with the non-woven fabric, the woven cloth, or the knitted cloth. A heat-retaining and moisturizing curing sheet for concrete that is characterized by being peeled off.

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