JP2022060937A - Roughening sheet, foam panel using the same, and manufacturing method of concrete skeleton using the form panel - Google Patents

Abstract

To provide a roughening sheet which can roughen a concrete skeleton surface with a simple method, which can control the accuracy of roughening, and which is hardly broken when removing a form, to provide a form panel including the roughening sheet, and to provide a manufacturing method of concrete skeleton using the form panel.SOLUTION: A roughening sheet has a woven fabric using a multifilament, and a sheet-like thermoplastic resin layer laminated at least on one surface of the woven fabric. The woven fabric has an irregular pattern by ups and downs of the multifilament, and by transferring the irregular pattern of the woven fabric via the thermoplastic resin layer, irregularity is formed on a surface of a concrete skeleton. A form including the same, and a manufacturing method of a concrete skeleton using the form are provided.SELECTED DRAWING: Figure 2

Description

The present invention relates to a roughening sheet for roughening the surface of a concrete skeleton, a formwork panel using the roughening sheet, and a method for manufacturing a concrete skeleton using the formwork panel.

Concrete structures are used for buildings such as condominiums. In a concrete structure, a mortar is applied as a base to the surface of a concrete skeleton (hereinafter referred to as a concrete skeleton) (hereinafter referred to as a mortar base), and tiles are attached on the mortar base. There is something.

If the surface of the concrete skeleton after hardening is smooth, the mortar base will not ride well, the pasted tile and the mortar base will peel off together, and the tile will easily peel off from the building over time, which is extremely dangerous. .. Therefore, in order to increase the adhesive force between the concrete surface and the mortar, a coarsening method has been performed in which high-pressure water is sprayed on the hardened concrete with a high-pressure washer or the like to roughen the concrete surface (Patent Document 1). ..

In recent years, as a simpler method, a method of pasting a sheet having irregularities on the inside of a formwork used at the time of placing concrete and embossing the irregularities on the concrete surface has also been proposed (Patent Document 2).

Japanese Patent Laid-Open No. 2004-09221 JP 2006-336229

The construction method described in Patent Document 1 is good in terms of the adhesive force of the mortar, but it takes time and effort, the burden on the operator is heavy, and the shavings are scattered by finely scraping the concrete surface, so that the vicinity of the site There were problems in that it was necessary to give consideration to the above, curing was required as a countermeasure, and the accuracy of coarsening varied.

According to the construction method described in Patent Document 2, no special equipment or on-site curing is required. However, there is still a problem in that it takes time and effort to attach the sheet to the formwork at the construction site. In addition, as another problem, a part of the sheet may be damaged at the time of demolding and may remain attached to the surface of the concrete skeleton. If the sheet remains, there is a problem that the adhesive force between the mortar base and the concrete skeleton decreases when the mortar base is applied to the surface of the concrete skeleton in the subsequent process. In addition, since the sheet is damaged, it is difficult to reuse it and it is necessary to dispose of it, which causes problems in terms of economic rationality and consideration for the environment.

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to roughen the surface of a concrete skeleton by a simple method, it is possible to control the accuracy of coarsening, and a roughening sheet that is not easily damaged when demolding and the roughening sheet and the relevant mesh are provided. It is an object of the present invention to provide a formwork panel provided with a roughened sheet and a method for manufacturing a concrete skeleton using the formwork panel.

The above-mentioned problem has a woven and knitted fabric using a multifilament and a sheet-shaped thermoplastic resin layer laminated on at least one surface of the woven and knitted fabric, and the woven and knitted fabric has irregularities due to ups and downs of the multifilament. By having a pattern and transferring the uneven pattern of the woven and knitted fabric through the thermoplastic resin layer, it can be solved by a coarsening sheet that forms unevenness on the surface of the concrete skeleton.

Further, the above problem can be solved by a formwork panel in which the roughening sheet is attached to plywood.

Further, the above-mentioned problem is to cast concrete on the formwork assembled by using the formwork panel, and after the concrete is hardened, the formwork to which the coarsening sheet is attached is removed, and after the hardening is performed. This can be solved by a method for manufacturing a concrete skeleton in which the uneven pattern of the roughening sheet is transferred to the surface of the concrete skeleton and the unevenness is formed.

In the above-mentioned method for manufacturing a roughening sheet, a formwork panel, or a concrete frame, it is preferable that both the multifilament and the thermoplastic resin layer are made of a polyolefin resin. It is also preferable that the thickness of the thermoplastic resin layer is 30 to 150 μm. It is also preferable that the thermoplastic resin layer is laminated on the woven or knitted fabric by extrusion laminating. It is also preferable that the roughening sheet and the plywood are attached to the formwork panel with an adhesive.

According to the present invention, the surface of the concrete skeleton can be roughened by a simple method, the accuracy of coarsening can be controlled, and the roughening sheet that is not easily damaged when the formwork is removed. It is possible to provide a formwork panel provided with a coarsening sheet and a method for manufacturing a concrete skeleton using the formwork panel.

The schematic diagram which shows one Embodiment of the coarsening sheet. The figure which schematically showed the cross section at the time of concrete construction using the roughening sheet of FIG. It is a figure which shows the structure of the structure of the specimen used in the strain followability test. This is an example of a graph used to obtain the elongation rate T until the tile is completely peeled off.

Hereinafter, an embodiment of the coarsening sheet of the present invention (hereinafter, may be simply referred to as a sheet) and a method of manufacturing a concrete skeleton using the coarsening sheet will be described, but the technique of the present invention will be described. The target range is not limited to this embodiment, and the configuration can be appropriately changed according to the construction content and the like.

1 and 2 show an embodiment of a coarsening sheet. As shown in FIG. 1, the coarsening sheet 1 of the present embodiment is formed by laminating a thermoplastic resin layer 3 on a woven and knitted fabric 2 using a multifilament. As will be described in detail later, in the roughening sheet 1 of the present embodiment, the thermoplastic resin layer 3 is arranged on one surface, and the protective layer 7 is further arranged on the other surface. In the example of FIG. 2, the coarsening sheet 1 made of the woven and knitted fabric 2 of the multifilament 4 in which the thermoplastic resin layer 3 and the protective layer 7 are laminated is adhered so that the protective layer 7 faces the plywood 8. The coarsening sheet 1 is fixed to the plywood 8 by the agent 6 to form a formwork panel. Then, when concrete is placed as a formwork, the concrete 5 is filled so as to be in contact with the surface of the thermoplastic resin layer 3.

As the multifilament, drawn yarn formed by a known production method can be used. The multifilament is made by combining a large number (for example, 30 to 200) of low fineness single yarns into a yarn. Woven and knitted fabrics using multifilaments have strength and suppleness, and are excellent in handleability. In addition, since the multifilament is twisted in a bundled state so that each single yarn does not fall apart, the cross section is substantially circular, and the woven and knitted fabric using the multifilament is a woven and knitted fabric using flat yarn. Compared to this, the surface tends to be uneven, making it ideal as a roughening sheet.

The main raw material constituting the multifilament is not particularly limited and may be appropriately selected from thermoplastic resins such as polyester, polyamide, polyolefin and polyvinyl alcohol, but it is particularly desirable to use a polyolefin resin. Polyolefin-based resin has a small specific gravity, and the woven and knitted fabric can be made into a durable sheet. Further, the thermoplastic resin layer is preferably a polyolefin resin for the reason described later, and if the woven and knitted fabric and the thermoplastic resin layer are to be firmly adhered by extrusion laminating, the multifilament is also a polyolefin resin. It is preferable to have. Examples of the polyolefin resin include linear low-density polyethylene, branched low-density polyethylene, high-density polyethylene, ethylene-vinyl acetate copolymer, ethylene- (meth) acrylic acid alkyl ester copolymer, or metallocene catalyst. The produced polyethylene-based resin such as an ethylene / α-olefin copolymer; or a polypropylene-based resin such as polypropylene, a propylene-ethylene block copolymer, or a propylene-ethylene random copolymer is used. These may be used alone or in admixture of two or more. Of these, polypropylene, which can obtain high strength due to the stretching effect, is preferable.

The fineness of the multifilament is not particularly limited, but is preferably in the range of 300 to 3,000 decitex (hereinafter referred to as dt), and more preferably in the range of 500 to 2,000 dt. preferable. If the fineness is less than 300 dt, the mechanical properties of the woven and knitted fabric may be insufficient, and the surface unevenness of the woven and knitted fabric may be insufficient, which is not preferable. Further, if it exceeds 3,000 dt, the flexibility may be insufficient, which is not preferable. The twist to be applied to the multifilament is appropriately selected, but it is preferably in the range of 15 to 200 times / m. It is not preferable because the unevenness may be easily insufficient. Further, if the number of twists exceeds 200 times / m, the flexibility is impaired, and in the extrusion lamination, the thermoplastic resin layer is less likely to be entangled with the multifilament, and sufficient adhesion may be difficult to obtain.

The above multifilaments are woven and knitted to form a woven and knitted fabric. In the sheet of the present embodiment, the multifilaments constituting the woven and knitted fabric regularly repeat ups and downs, so that the multifilaments intersect and overlap each other. Using the uneven pattern caused by the ups and downs of this multifilament, the surface of the concrete skeleton is formed with irregularities. Examples of the woven structure when the multifilament is used as a woven fabric include plain weave, twill weave, leno weave, and imitation weave. When the multifilament is used as a knitted fabric, the knitting structure may be either weft knitting or warp knitting, and specific examples thereof include tricot knitting, Milanese knitting, and Russell knitting.

It is desirable that the woven and knitted fabric has an uneven pattern with a sufficient height difference on the surface, the arrangement of the uneven pattern is as uniform as possible, the woven and knitted fabric has little expansion and contraction, and the thermoplastic resin layer can be easily laminated. .. For this reason, woven fabrics are preferable to knitted fabrics.

If the texture or stitches of the woven knitted fabric are made into a coarse mesh with wide open stitches, the thermoplastic resin layer may be easily torn at the textured portion or the stitched portion. In addition, it may be difficult to secure the adhesive strength between the woven and knitted fabric and the thermoplastic resin layer. When the coarse mesh is used as a coarsening sheet, the concrete may excessively bite into the textured portion or the knitted portion, making it difficult to remove it from the concrete after hardening. Therefore, it is particularly preferable that the woven and knitted fabric has a plain weave or twill weave structure and is woven so that at least one of the warp yarns and the weft yarns fills the voids. For example, the distance between the convex portions transferred to the concrete is preferably in the range of 0.5 mm to 5 mm, and the driving density in the case of making a woven fabric is preferably in the range of 10 to 30 lines / 2.54 cm. More preferably, it is in the range of 14 to 22 lines / 2.54 cm. It is considered that the driving density affects the interval of the unevenness transferred to the concrete, and also affects the peeling resistance of the tile when the tile is attached to the placed concrete. From this point of view, it is preferable that the driving density is within the above range.

In the coarsening sheet of the present embodiment, a sheet-shaped thermoplastic resin layer is laminated on the woven and knitted fabric made of the multifilament. The thermoplastic resin layer is a layer provided on one side of the woven and knitted fabric and is a layer that comes into contact with the concrete to be roughened. When the uneven pattern of the woven and knitted fabric is transferred, if the woven and knitted fabric is in direct contact with the concrete, the multifilament fibers bite into the concrete and it becomes difficult to peel it off from the concrete. Even if it can be peeled off from the concrete, the fibers are left on the concrete side, which causes deterioration of the quality of the concrete skeleton and causes defects when the tiles are attached in the subsequent process. In addition, the fibers are damaged in the process of peeling from the concrete, and concrete pieces remain in the fibers, which makes it difficult to reuse the coarsening sheet. Furthermore, by applying the multifilament, which is an aggregate of fine fibers, to the concrete surface before hardening, it may absorb the moisture of the concrete and hinder the hardening of the concrete.

The resin used for the thermoplastic resin layer is not particularly limited as the main raw material used, and may be appropriately selected from the same thermoplastic resins as the materials constituting the multifilament. Among them, the resin used for the thermoplastic resin layer is preferably a resin having a high affinity with the resin used for the multifilament constituting the woven and knitted fabric. After the concrete is hardened, the coarsening sheet of the present embodiment needs to be peeled off from the surface of the concrete skeleton. At that time, if the peel strength between the woven and knitted fabric and the thermoplastic resin layer is weak, the sheet may be peeled off between the woven and knitted fabric and the thermoplastic resin layer depending on the conditions. In order to obtain high affinity, it is preferable that the resin system is the same, and it is preferable that both the multifilament and the thermoplastic resin layer are resins of the same system. Further, when the roughening sheet is peeled off from the surface of the concrete skeleton, it is desired that the concrete does not firmly adhere to the thermoplastic resin layer. From this point of view, the thermoplastic resin layer is preferably hydrophobic. Further, in order to transfer the uneven pattern of the woven and knitted fabric to the surface of the concrete frame, it is preferable that the thermoplastic resin layer has flexibility so as to follow the uneven pattern of the woven and knitted fabric. Further, since concrete is strongly alkaline, it is preferable that the thermoplastic resin layer in contact with the concrete surface has alkali resistance. From these viewpoints, the resin used for the thermoplastic resin layer is preferably a polyolefin resin. When the sheet is peeled off from the surface of the concrete skeleton, the thermoplastic resin layer more preferably contains a polyolefin-based thermoplastic elastomer because the elastic resin layer is less likely to be torn and debris is less likely to remain.

The resin constituting the coarsening sheet includes an antioxidant, an ultraviolet absorber, a light stabilizer, a dispersant, a lubricant, an antistatic agent, a pigment, an inorganic filler, and a cross-linking agent within the range not deviating from the gist of the present invention. , Foaming agents, nucleating agents and other commonly used additives may be blended.

The thermoplastic resin layer may be laminated by a known method such as an extrusion laminating method, a calendar method, a coating method, or a dipping method. The uneven pattern of the woven and knitted fabric needs to be reflected on the surface of the thermoplastic resin layer, and the thermoplastic resin layer is required to be able to be laminated so as to follow the uneven pattern of the woven and knitted fabric. Therefore, it is preferable to laminate the thermoplastic resin layer by the extrusion laminating method.

The extrusion laminating method is a method in which a thermoplastic resin is extruded into a film in a molten state with respect to a base material, and then cooled and pressure-bonded to be laminated. According to the extrusion laminating method, not only the molten resin can be made to bite into the base material, but also the layers can be adhered and laminated by utilizing the affinity between the molten resin and the base material. When the thermoplastic resin layer is made to bite into the base material with high pressure and laminated, the uneven pattern of the woven and knitted fabric is impaired. Therefore, it is preferable to use the affinity between the molten resin and the base material for laminating. According to the laminating by the extrusion laminating method, the dissolved resin bites into the woven and knitted fabric appropriately, so that the multifilament is not completely fixed and the coarsening sheet remains in a state where the multifilament has a degree of freedom. It is formed. The roughened sheet has irregularities on the concrete surface, but if the unevenness pattern of the roughened sheet bites into the concrete more than necessary, it becomes difficult to remove the roughened sheet after curing, and the sheet becomes difficult. It is pulled by the concrete surface, and depending on the conditions, the sheet may be damaged. If the degree of freedom of the multifilament remains, even if the uneven pattern bites into the concrete, the multifilament may be deformed to avoid damage to the sheet.

The thickness of the thermoplastic resin layer is not particularly limited. However, if the thickness of the thermoplastic resin layer is too thick, it may be difficult to reflect the uneven pattern of the woven and knitted fabric on the surface of the roughened sheet depending on the conditions. Further, if the thickness is too thin, depending on the conditions, it may be difficult to obtain sufficient adhesion between the thermoplastic resin layer and the woven and knitted fabric, and the thermoplastic resin layer may be easily damaged. Therefore, the thickness of the thermoplastic resin layer is preferably about 30 to 150 μm.

The tensile strength or tear strength of the coarsening sheet is not particularly limited and does not need to be extremely high. However, the roughening sheet needs to be peeled off from the surface of the concrete skeleton after the concrete is hardened. It is preferable that the tensile strength and the tear strength are high to some extent in order to surely prevent the sheet from being damaged. If these are low, it is assumed that the coarse sheet may be torn and remain on the concrete skeleton depending on the conditions when it is peeled off from the surface of the concrete skeleton. As will be described later, when the coarsening sheet is attached to the plywood and used, the coarsening sheet may be wrinkled. When the sheet is peeled off, stress is concentrated on the wrinkled part, and the sheet is easily torn. The coarsening sheet of the present embodiment uses a multifilament woven and knitted fabric, and can have high tensile strength. Thereby, the above-mentioned problem of tearing can be solved. Further, if the tensile strength of the coarsening sheet is high, the effect of suppressing the warp of the formwork can be obtained by completely adhering the coarsening sheet. Further, if the thermoplastic resin layer is laminated by the extrusion laminating method as described above, high tear strength can be maintained. For example, the tensile strength according to JIS L 1096 can be 1,000 to 5,000 N / 5 cm, and the tear strength according to the JIS L 1096 A-1 method (single tongue method) can be 50 to 1,000 N.

The coarsening sheet obtained as described above may be used by being attached to a formwork assembled according to the shape of the concrete to be manufactured. The material of the formwork is not particularly limited and may be made of wood, resin or metal, but plywood is used for the formwork used when placing concrete that requires coarsening. In many cases, the coarsening sheet is preferably attached to a formwork using plywood. The roughening sheet and formwork can also be attached at the construction site using nails, tackers, adhesives, adhesive tapes, and the like. In this case, it is necessary to cut the sheet according to the dimensions of the formwork at the construction site and attach the sheet. Further, it is often difficult to sufficiently adhere the entire surface of the sheet to the formwork, the sheet and the formwork are not partially adhered to each other, and the sheet is liable to wrinkle. If the sheet is wrinkled, this wrinkle pattern may be transferred to the concrete on which it is manufactured. In addition, if the adhesion between the sheet and the formwork is limited to partial adhesion, when the sheet is removed after the concrete is hardened, stress concentrates in the vicinity of the adhesive part and the sheet is easily damaged, so the sheet is surely reused. It is not always possible.

Since the occurrence of wrinkles causes the above-mentioned problems, it is preferable to ensure that the bonded surface is uniformly bonded as a whole when the roughening sheet and the mold are bonded. .. In order to adhere the adhesive surface uniformly over the entire surface, it is preferable to arrange the adhesive on the entire adhesive surface using a roll coater or the like and bond the adhesive surface. Therefore, it is preferable to bond the sheets in advance at the stage of the formwork material (mainly plywood) to form a formwork panel, and bring the formwork panel to the construction site to assemble the formwork. If the sheet and plywood are bonded in advance, it is not necessary to perform the bonding work on site, and it is possible to proceed with the construction efficiently.

As the adhesive, known adhesives can be used. The adhesive may be either a water-soluble adhesive, a water-based adhesive such as an aqueous emulsion adhesive, or a solvent-type adhesive, and may be appropriately selected in view of the adhesiveness between the sheet and the plywood. Further, the coating amount can be appropriately selected from the viewpoint of their types and adhesiveness.

When the roughening sheet and plywood are attached with an adhesive to form a formwork panel, heat is separately applied to the surface of the roughening sheet opposite to the surface on which the thermoplastic resin layer of the woven and knitted fabric is arranged. It is preferable to provide a protective layer made of a plastic resin. Depending on the type or conditions of the adhesive used, most of the adhesive may soak into the woven and knitted fabric when it comes into contact with the woven and knitted fabric, and sufficient adhesion may not be obtained. By providing the protective layer, it is possible to prevent the adhesive from penetrating into the woven and knitted fabric and to arrange the adhesive more evenly. The protective layer preferably has the same structure as the thermoplastic resin layer. If the front and back configurations are different, curling may occur depending on the conditions. Curls can also cause poor adhesion. By forming the protective layer in the same structure as the thermoplastic resin layer, it is possible to prevent curling.

If a protective layer is provided, the sheet is secured to the plywood via an adhesive applied to the protective layer. It is preferable that the surface of the protective layer is subjected to a corona discharge treatment for the purpose of further enhancing the adhesiveness between the protective layer and the adhesive. This makes it possible to increase the adhesive force between the sheet and the plywood as compared with the adhesive force between the thermoplastic resin layer and the concrete skeleton. According to such a configuration, for example, after the concrete is hardened, the formwork and the sheet can be removed as a unit from the concrete skeleton in a state where the sheet is attached to the formwork.

When concrete is constructed using the coarsening sheet, it can be constructed in the same manner as a normal concrete construction method except that a formwork to which the coarsening sheet is attached is used. After the concrete is hardened, the formwork to which the coarsening sheet is attached is removed, so that unevenness is formed on the surface of the hardened concrete by transferring the uneven pattern of the roughening sheet.

The coarsening sheet of the present embodiment has a configuration in which a thermoplastic resin layer is arranged on one surface of the woven and knitted fabric, and a protective layer is arranged on the other surface of the woven and knitted fabric. As long as the coarsening sheet includes the woven and knitted fabric and the thermoplastic resin layer, the protective layer may be omitted, or the coarsening sheet may be configured to include other layers.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to the following Examples.

[Example 1]
<Making a roughening sheet>
A polypropylene multifilament (fineness 760 dt, number of combined yarns 120, 100 m / twist) was used for the warp and weft yarns and woven into a plain weave with a driving density of 18 × 20 yarns / 2.54 cm to obtain a woven fabric. Next, a mixture of 80% by weight of a polyolefin-based thermoplastic elastomer (reactor type TPO) and 20% by weight of linear low-density polyethylene was prepared and laminated on both sides of the woven fabric to a thickness of 70 μm by an extrusion laminating method. bottom. Then, one side was subjected to a corona discharge treatment to obtain a sheet a having the configurations shown in FIGS. 1 and 2. The sheet a had the following physical properties. The tensile strength according to JIS L 1096 was 2,160 N / 5 cm in length and 2,332 N / 5 cm in width. The tear strength by the JIS L 1096 A-1 method (single tongue method) was 180 N in the vertical direction and 150 N in the horizontal direction.

[Comparative Example 1]
A commercially available polypropylene / polyethylene thermal bond nonwoven fabric (weight: 200 g / m ² ) was prepared and used as a sheet b.

[Comparative Example 2]
Polypropylene is molded by the inflation method using a round die with a groove on the die lip to produce a polypropylene film (with a basis weight of 60 g / m ² ) having irregularities formed along the longitudinal direction on one side, and this is used as a sheet. It was set to c.

<Test 1: Roughing test>
A wooden formwork (300 mm × 360 mm × 100 mm) was prepared, and the sheets shown in Example 1, Comparative Example 1 and Comparative Example 2 were laid on the bottom surface. Next, concrete was poured from the top surface. The mold was removed on the 5th day of the material age, and each sheet was peeled off on the 12th day of the material age. Table 1 shows the results of evaluating the roughened condition and workability in three stages.

Example 1: The woven uneven pattern of the sheet a was transferred to the surface of the concrete from which the sheet 1 was peeled off, and the unevenness was uniform and the surface was roughened. It was easy to attach and remove the sheet, and even when looking at the sheet a after removal, there was almost no adhesion of concrete.
Comparative Example 1: Many fiber pieces were attached to the surface of the concrete from which the sheet b was peeled off. Since the sheet b absorbed the moisture of the concrete before hardening, the concrete surface was not sufficiently hardened and was brittle and easily collapsed.
Comparative Example 2: A striped uneven pattern by the sheet c was transferred to the surface of the concrete from which the sheet c was peeled off. It was difficult to lay the sheet c on the formwork without wrinkles and fix it, and since concrete was poured with some wrinkles on the sheet c, the wrinkle pattern was also transferred to the concrete. There was almost no adhesion of concrete to the sheet c after removal.

<Test 2: Plywood bonding test>
An aqueous emulsion adhesive (Bond CVC360H / Hardener NV manufactured by Konishi Co., Ltd.) was applied to the softwood plywood with a roll coater, and the sheets of Example 1 and Comparative Example 2 were placed and compacted, respectively, and 1 at outside temperature. After curing for a week and pasting, a formwork panel in which the plywood and the sheet were integrated was obtained. The sheet of Example 1 was attached so that the corona discharge-treated surface of the sheet a and the plywood faced each other. The obtained formwork panel was subjected to a first-class immersion peeling test according to the Japanese Agricultural Standards for plywood (Ministry of Agriculture, Forestry and Fisheries Notification No. 303, 2014) and a 180-degree peeling adhesive strength test (test) using Shimadzu Autograph AG5000A. One-sided width: 25 mm, tensile speed: 200 mm / min). The results obtained are shown in Table 2.

Example 1: In the formwork panel to which the sheet a of Example 1 was attached, there was no abnormality in the appearance in the type 1 immersion peeling test. The 180 degree peeling adhesive strength test was also a numerical value due to the material of the softwood plywood breaking, and showed sufficient peeling strength.
Comparative Example 2: There was no abnormality in the appearance of the formwork panel to which the sheet c of Comparative Example 2 was attached in the Class 1 dip-peeling test. In the 180-degree peel-off adhesive strength test, the sheet c was in a state of being torn off immediately, and was not in a state of being measurable in the same manner.

<Test 3: Preparation of concrete skeleton>
A formwork was assembled using the formwork panel to which the sheet a of Example 1 was attached, concrete was cast, and the material was cured until the 7th day of age. The formwork was removed from the hardened concrete to create a concrete skeleton.

The uneven pattern of the sheet a was transferred to the surface of the concrete skeleton, and obvious unevenness was formed, resulting in a roughened state. The unevenness was uniform. Demolding was not particularly difficult, and even when looking at the sheet a after demolding, there was almost no adhesion of concrete, and the formwork was in a state where it could be reused. Further, the sheet a itself was not damaged, and the sheet 1 was in a state where it could be used repeatedly. The base mortar was applied to the 58-day-old concrete skeleton manufactured using the sheet a, and the tiles were attached with the mortar, but there was no problem in the attaching work and the adhesiveness of the tiles.

<Test 4: Strain followability test>
A steel formwork (100 mm × 400 mm × 100 mm) and a formwork in which the formwork members forming two sides in the longitudinal direction of the formwork are recombined into a formwork panel to which the sheet a of Example 1 is attached are formed. I prepared it. Concrete (water-cement ratio 47%, nominal strength 33 N / mm ² ) was poured into each formwork. The next day, each formwork was removed from the hardened concrete to obtain a prismatic specimen a without a pattern and a prismatic specimen a to which the uneven pattern of the sheet a was transferred. The unpatterned specimen on the 57th day of the material age was subjected to roughening by ultra-high pressure washing to obtain a prismatic specimen b having been roughened. Ultra-high pressure washing was performed on two opposing sides of the unpatterned specimen extending longitudinally.

As shown in FIG. 3, mortar was applied to the uneven pattern surface of the specimen a and the rough surface of the specimen b, respectively, and a plurality of tiles were attached to each specimen. The positions where the tiles are attached are as follows. A vertical line was assumed at the center of the mortar-coated surface in the lateral direction, and a plurality of tiles were attached along the vertical line. As shown in FIG. 3, a total of 5 tiles were attached to one surface of the specimen, and a total of 5 tiles were attached to the other surface of the specimen. The tiles are attached so that the edge of the tile at the lower end is 72.5 mm from the lower end of the specimen and the edge of the tile at the upper end is 72.5 mm from the upper end of the specimen. The tiles were spaced 5 mm apart. The shape of the tile is a square of 45 mm × 45 mm. After the tiles are attached, they are cured until the age of 83 days, and the prismatic specimen a'with the tiles attached to the two sides of the specimen a and the prismatic specimens with the tiles attached to the two sides of the specimen b. Specimen b'was obtained.

As shown in FIG. 3, a strain gauge is attached to the center position in the longitudinal direction and the lateral direction of the specimen, and JIS A 1108 (compressive strength test method for concrete) is applied to the specimen a'and the specimen b'. Based on the above, a strain tracking test was performed. The strain of concrete was measured using a strain gauge PL-60-11 manufactured by Tokyo Measurement Research Institute Co., Ltd. The tile strain was measured using the company's PFL-10-11 and recorded using the company's strain recorder DC204R. The results obtained are shown in Table 3. The "strain transmission rate α" indicates the ratio of tile strain to concrete strain. "Elongation T until the tile is completely peeled off" is the area between the tile strain-concrete strain curve and the concrete strain axis from the point where the tile strain starts to decrease to the point where the tile is completely peeled off (figure). 4 The shaded area) is shown.

The specimen a'obtained by using the sheet a of Example 1 has an elongation degree T until the tiles are completely peeled off, as compared with the specimen b'which has been roughened by ultra-high pressure washing. It is five times more expensive and requires a lot of energy for the tiles to peel off. That is, the roughening by the sheet a of Example 1 is more likely to obtain the peeling resistance of the tile than the roughening by the ultra-high pressure washing. The reason why the elongation T until the tile is completely peeled off is 150,000 or more, especially 200,000 or more, is that the unevenness of the concrete formed by the sheet a of Example 1 is at an appropriate depth and interval. It is presumed that this is due to the uniformity.

1 Roughening sheet 2 Woven knitted fabric 3 Thermoplastic resin layer 4 Multifilament 5 Concrete 6 Adhesive 7 Protective layer 8 Plywood

Claims (7)

It has a woven and knitted fabric using a multifilament and a sheet-shaped thermoplastic resin layer laminated on at least one side of the woven and knitted fabric.
The woven and knitted fabric has an uneven pattern due to the ups and downs of the multifilament.
By transferring the uneven pattern of the woven and knitted fabric through the thermoplastic resin layer,
A roughening sheet that creates irregularities on the surface of the concrete frame. The coarsening sheet according to claim 1, wherein both the multifilament and the thermoplastic resin layer are made of a polyolefin resin. The coarsening sheet according to claim 1 or 2, wherein the thermoplastic resin layer has a thickness of 30 to 150 μm. The coarsening sheet according to any one of claims 1 to 3, wherein the thermoplastic resin layer is laminated on the woven and knitted fabric by extrusion laminating. A formwork panel to which the coarsening sheet according to any one of claims 1 to 4 is attached to plywood. The formwork panel according to claim 5, wherein the roughening sheet and plywood are attached by an adhesive. Concrete is placed on the formwork assembled by using the formwork panel according to claim 5 or 6, and after the concrete is hardened, the formwork to which the coarsening sheet is attached is removed to obtain the cured formwork. A method for manufacturing a concrete skeleton in which the uneven pattern of a roughening sheet is transferred to the surface of the concrete skeleton to form unevenness.

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