TW202317374A - Structure protection sheet, and production method for reinforced structure - Google Patents

Abstract

Provided is a structure protection sheet that enables a substantial reduction in construction time when providing a protection layer on a surface of a structure of, e.g., concrete, is capable of protecting the structure on a long-term basis, exhibits excellent strength, and does not rupture or undergo permanent deformation when attached to the structure. The structure protection sheet comprises a polymer cement cured layer provided on the structure side and a resin layer provided on the polymer cement cured layer, the structure protection sheet being characterized by having a Young's modulus of 20-300 MPa.

Description

Structure protection sheet and method for manufacturing reinforced structure

The invention relates to a structure protection sheet and a method for manufacturing the reinforced structure. More specifically, the present invention relates to a structure protection sheet and a method of manufacturing a reinforced structure using the structure protection sheet. When the structure protection sheet is provided with a protective layer on the surface of a structure such as concrete, It can greatly shorten the construction period, and at the same time, it can protect the structure for a long time, and it can prevent tearing or permanent deformation when it is attached to the structure.

Civil engineering structures such as roads, bridges, tunnels, sluices and other river management facilities, sewer ditches, harbor walls, etc., need to be repaired and reinforced as they age. Repair works are carried out by repeatedly applying coating materials several times after repairing missing parts, weak parts, etc. On the other hand, the reinforcement work is performed by repeatedly applying a reinforcement coating material to the entire portion to be reinforced.

Repeated coating in such repair work, reinforcement work, etc., is carried out on the concrete in the order of primer, mid-coat, top coat, etc., but usually in order to dry the coating, the coating process of each mid-coat, etc. cannot Continuously, for example, it takes at least 5 days for a total of 5 coats of primer coating, 1st intermediate coating, 2nd intermediate coating, 1st top coating, and 2nd top coating. Moreover, since the painting is done outdoors, it is affected by the weather, and it cannot be dried sufficiently in rainy weather, or the painting work itself cannot be carried out. Therefore, it is difficult to shorten the construction period, the labor cost is high, and due to the influence of the external environment (humidity, temperature, etc.) during the coating process, it is difficult to stabilize the construction and the quality of the coating film (film thickness, surface roughness, water content, etc.) .

In addition, although painting is carried out by leveling, spraying, etc., stable repairs, reinforcements, etc. through uniform coating largely depend on the skills of the craftsman. Therefore, the quality of the coating film also varies depending on the skill of the craftsman. Furthermore, with the aging of construction workers and the decrease in the population, the number of workers engaged in concrete repair work, reinforcement work, etc. is decreasing. Recently, a simpler repair method that can be performed by an unskilled craftsman is required.

As a technique for solving these problems, for example, Patent Document 1 proposes a sheet and a method that are simple, low-cost, shorten the construction period, and reliably prevent concrete from deteriorating. This technology is a concrete repair method that attaches a concrete repair sheet to the concrete surface to be repaired with an adhesive for construction, and then applies paint to the opposite side of the concrete surface to which the concrete repair sheet is attached. side surface layer. The concrete repair sheet includes an intermediate layer having a resin film and a surface layer made of a fabric material, and the surface layer is laminated on both surfaces of the intermediate layer via an adhesive resin.

In addition, the coating materials have also been improved. For example, in Patent Document 2, a method for protecting concrete structures is proposed, which uses a method that can prevent alkaline aggregate reaction, has excellent followability to cracks in concrete structures, and does not rise even if the temperature rises after the coating film is formed. Coating materials that cause coating film expansion and prevent concrete spalling. This technique is a method of forming a coating film of a foundation adjustment material on the surface of a concrete structure, and then forming a coating film on the surface of the coating film. The base adjustment material coating film is formed of a composition containing a cationic (meth)acrylic polymer emulsion and an inorganic hydraulic substance. The coating film formed on the surface of the base adjustment material coating film is a coating film composed of a composition containing an (meth)acrylic acid alkyl ester emulsion and an inorganic hydraulic substance, and the elongation rate at 20°C is 50~ 2000%, salt shielding property of 10 ^-2 ~10 ^-4 mg/cm ² · day, water vapor permeability of 5 g/m · day or more, film thickness of 100 ~ 5000 μm. [Prior Art Documents] [Patent Documents]

[Patent Document 1] Japanese Patent Laid-Open No. 2010-144360 [Patent Document 2] Japanese Patent Laid-Open No. 2000-16886

[Problem to be solved by the invention]

Conventional concrete repair sheets such as Patent Document 1 have differences in adhesive force between the base material and other layers (for example, adhesive layer, reinforcing member, etc.), differences in elongation of the base material, adhesive layer, and reinforcing member, etc., and adhesives. Problems to be solved such as the problem of the adhesive strength of the layer and the concrete. Specifically, the base material and the reinforcing member are bonded together through the adhesive layer. When stress is applied to the concrete repair sheet during construction or the concrete repair sheet after construction, the base material, adhesive layer, and The difference in elongation of the reinforcing member and the like is a cause of delamination of the layer interface based on the difference between the adhesive force between the base material and the adhesive layer and the adhesive force between the adhesive layer and the reinforcing member.

In addition, although the adhesive layer provided on the concrete repair sheet is softened by heating and bonded to the concrete, if sufficient adhesive strength is not obtained, the concrete repair sheet may be peeled from the surface of the concrete and cannot function as a repair sheet. function of the material. In addition, after the construction of the concrete repair sheet, the concrete sometimes expands over time. This phenomenon is due to the existence of the repair sheet with low water vapor permeability, and the water vapor inside the concrete cannot escape. Caused. Furthermore, when attaching the concrete repair sheet to concrete, once the concrete repair sheet is attached to the structure and aligned, it must stretch to prevent wrinkling and maintain the attachment in the desired shape and position. However, the conventional concrete repair sheet has a very large elongation rate with respect to the applied stress, so there is a problem of tearing or permanent deformation.

In addition, as explained in the column of the above-mentioned background technology, the method of forming a coating film by on-site coating takes 1 day for each layer of coating. Taking the primer to top coating as an example, it takes 6 days to form 6 layers of coating film. Day, and there are also problems such as uneven film thickness, surface roughness, moisture content, etc., which are difficult to stabilize.

In addition, since the repair objects of concrete repair sheets are usually large concrete members such as roads, bridges, tunnels, sluices and other river management facilities, sewer ditches, and bay walls, etc., the concrete repair sheets themselves also need sufficient strength ( Tensile strength, bending strength, hardness, surface strength, punching strength and toughness, etc., are referred to in this specification below as the same), but there is a problem that it is difficult to say that the conventional concrete repair sheet has sufficient strength.

The present invention is made to solve the above problems, and its object is to provide a structure protection sheet and a method of manufacturing a reinforced structure using the structure protection sheet. The structure protection sheet is provided with a protective layer on concrete, etc. When attaching to the surface of a structure, the construction period can be greatly shortened, and at the same time, it can protect the structure for a long time, has excellent strength, and will not tear or permanently deform when attached to the structure. [means used to solve a problem]

The inventors of the present invention have studied a concrete protection sheet, which can protect the concrete stably for a long time without passing through the construction method of forming a layer on the surface of the concrete by means of coating, while preventing tearing or permanent deformation during construction. As a result, the concrete protection sheet is endowed with performance corresponding to the characteristics of concrete. Specifically, it is further equipped with the ability to follow the cracks or expansion that appear in the concrete, and to prevent deterioration factors such as water and chloride ions from penetrating into the concrete. The present invention has been accomplished by realizing the appropriate Young's modulus of the concrete protection sheet itself while achieving water resistance, salt-shielding properties, neutralization prevention properties, and water vapor permeability that discharges moisture in the concrete as water vapor. . This technical idea can also be applied to structures other than concrete as a structure protection sheet.

(1) The structure protection sheet of the present invention is a structure protection sheet provided with a polymer cement hardened layer disposed on the structure side and a resin layer disposed on the polymer cement hardened layer, characterized by Young's The modulus is 20~300 MPa.

According to the present invention, the polymer cement hardened layer provided on the structure side has excellent adhesion to the structure, has appropriate strength and elongation, and can prevent it from being attached to the structure and positioning it due to stretching. caused by tearing or permanent deformation problems. In addition, since the structure protection sheet can be mass-produced through the coating and drying steps of the factory production line, it can achieve cost reduction, greatly reduce on-site operation time, and long-term protection of structures.

In the structure protection sheet of the present invention, the Young's modulus is preferably 10 to 300 MPa in the range of a stress of 2.0 MPa or less and an elongation of 5% or less.

According to the present invention, after the structure protection sheet is attached to the structure and positioned, it exhibits sufficient elasticity when stretched.

The structure protection sheet of the present invention may have a Young's modulus adjustment layer in contact with the cured polymer cement layer.

According to the present invention, the elasticity of the structure protection sheet can be controlled through the Young's modulus adjustment layer, and the structure protection sheet of the present invention can be properly prevented from being torn due to stretching after the structure protection sheet is attached to the structure and positioned. problems of cracking or permanent deformation.

In the structure protection sheet of the present invention, the aforementioned Young's modulus adjustment layer is selected from the group consisting of a non-woven fabric layer, an elastic layer, a metal fiber layer, a particle dispersion layer, acicular and rod-shaped dispersion layers, and a mesh structure layer. At least one of the group is preferable.

According to the present invention, a Young's modulus in a desired range can be appropriately imparted to the structure protection sheet of the present invention.

In the structure protection sheet of the present invention, the polymer binder hardened layer is a layer containing a binder component and a resin, and preferably contains 10% by weight or more and 40% by weight or less of the resin. Preferably, more than 20% by weight and less than 30% by weight of resin is more preferred.

According to the present invention, by controlling the ratio of the binder component to the resin component, it is easier to form a polymer binder hardened layer, and because the polymer binder hardened layer is easy to become a layer with excellent followability and good compatibility, it has improved The tendency of the layer itself to adhere. Furthermore, the binder component contained in the polymer binder cured layer on the structure side functions to improve the adhesion to structures such as concrete.

(2) The method of manufacturing a reinforced structure of the present invention is a method of manufacturing a structure using the above-mentioned structure protection sheet of the present invention, which is characterized in that the above-mentioned structure protection sheet is applied after the adhesive is applied to the structure. piece.

According to the present invention, since only the structure protection sheet composed of a layer not including a base material or a reinforcing member is used, it can be easily attached to the surface of a structure. As a result, even an unskilled worker can stably install a structure protection sheet with excellent strength on the surface of a structure, greatly shortening the construction period, protecting the structure for a long time, and preventing stretching after positioning. resulting tearing or permanent deformation.

In the method of manufacturing the reinforced structure of the present invention, a primer layer may be provided between the structure and the adhesive.

According to the present invention, since the undercoat layer provided between the structure and the adhesive acts to enhance mutual adhesion, the structure protection sheet can stably protect the structure for a long period of time. [Efficacy of the invention]

According to the present invention, it is possible to provide a structure protection sheet and a method of manufacturing a reinforced structure using the structure protection sheet, which can protect structures such as concrete for a long period of time, and at the same time, when attached to the structure Capable of resisting tearing or permanent deformation. In particular, it is possible to provide a structure protection sheet, which is endowed with performance corresponding to the characteristics of the structure, realizes tracking cracks or swelling that appear in the structure, and prevents deterioration factors such as water and chlorine ions from penetrating into the structure, It has permeability to discharge moisture, deterioration factors, etc. in the structure, and improves strength, etc. Furthermore, it has the advantage of being able to improve the stability and uniformity of the quality compared with the layer formed by manual coating conventionally.

[Mode for Carrying Out the Invention]

Hereinafter, the structure protection sheet of the present invention and the construction method using the protection sheet will be described with reference to the drawings. The present invention can be modified in various ways as long as it has technical features, and is not limited to the following description and the forms of the drawings.

[Structure Protection Sheet] As shown in FIG. 1 or FIG. 2(C), the structure protection sheet 1 of the present invention includes a polymer adhesive hardened layer 3 disposed on the structure 21 side and a resin layer 2 disposed on the polymer adhesive hardened layer 3 . The polymer binder hardened layer 3 and the resin layer 2 may be formed as a single layer or as a laminate, respectively. In addition, other layers may be provided between the polymer binder hardened layer 3 and the resin layer 2 according to required properties.

The structure protection sheet 1 of the present invention has a Young's modulus of 20 to 300 MPa. If the Young's modulus is less than 20 MPa, when the structure protection sheet 1 of the present invention is attached to the structure 21, tearing or permanent deformation will be caused when stretched for the purpose of eliminating wrinkles after positioning. If the Young's modulus exceeds 300 MPa, the structure protection sheet 1 of the present invention is too rigid, and when the structure protection sheet 1 of the present invention is attached to the structure 21, it cannot be stretched sufficiently after positioning. The lower limit of the Young's modulus of the structure protection sheet 1 of the present invention is preferably 30 MPa, and the upper limit is preferably 280 MPa. The above-mentioned Young's modulus can be measured using, for example, a known tensile testing machine.

Although such a Young's modulus can be achieved by appropriately selecting the material of the polymer cement hardened layer 3 constituting the structure protection sheet 1 of the present invention, since the structure protection sheet 1 of the present invention is constituted to have It is preferable that the cement hardened layer 3 is a Young's modulus adjustment layer 5 in a contact state, since the Young's modulus can be adjusted more easily. The Young's modulus adjustment layer 5 will be described later.

The structure protection sheet 1 of the present invention is preferably elastically deformed when stretched after the structure protection sheet 1 of the present invention is attached to the structure 21 and positioned. The elastic deformation of the structure protection sheet 1 of the present invention can prevent tearing or permanent deformation due to stretching. Specifically, the structure protection sheet 1 of the present invention is preferably elastically deformed in the range where the stress is 2.0 MPa or less and the elongation is 5% or less, and the Young's modulus in this range is 20 to 300 MPa. good.

The structure protection sheet 1 of the present invention preferably has a thickness distribution within ±100 μm. Since the structure protection sheet 1 has a thickness distribution within the above-mentioned range, even an unskilled worker can stably provide a layer with little variation in thickness on the surface of the structure 21 . In addition, by controlling the thickness distribution within the above range, it becomes easier to uniformly reinforce the structure. The hardened polymer cement layer 3 provided on the structure 21 side has excellent adhesion to the structure 21 , and since it has the Young's modulus adjustment layer 5 , it can impart characteristics that ensure strength. In addition, the resin layer 2 provided on the polymer cement cured layer 3 can impart properties such as water repellency, salt-shielding property, and neutralization prevention property. In addition, since the structure protection sheet 1 can be mass-produced through the coating step and drying step of the factory production line, it can realize cost reduction, greatly reduce on-site operation period, and long-term protection of structures. As a result, the construction period for sticking to the surface of the structure 21 can be significantly reduced, and the structure 21 can be protected for a long period of time.

Specific examples of each component will be described in detail below.

(construct) The structure 21 is a target member to which the structure protection sheet 1 of the present invention is applied. As the structure 21, the structure which consists of concrete is mentioned. The above-mentioned concrete is generally obtained by casting and curing a cement composition comprising at least cement-like inorganic substances, aggregates, admixture, and water. This type of concrete is widely used as civil engineering structures such as river management facilities such as road bridges, tunnels, and sluices, sewer ditches, and harbor walls. In the present invention, by applying the structure protection sheet 1 to the structure 21 made of concrete, it has the ability to follow the cracks or expansion that appear in the concrete, so that deterioration factors such as water and chloride ions do not penetrate into the concrete, and the The particular advantage is that the moisture in the concrete escapes as water vapour.

(Polymer binder hardened layer) As shown in FIG. 2(C) , the cured polymer cement layer 3 is a layer arranged on the structure side. This polymer cement hardening layer 3 can be a single layer or a laminated layer. Whether to form a single layer or a laminated layer will consider the overall thickness, the function to be given (followability, adhesion to structures, etc.), the production line of the factory, and the production cost. It can be set arbitrarily. For example, if the production line is short and the predetermined thickness cannot be achieved with a single layer, it is possible to form a layer that is repeatedly coated with two or more layers. For example, in double-coating, the first layer is dried and the second layer is formed. In addition, the hardened polymer binder layer 3 may have a structure in which layers with different properties are laminated. For example, by forming a layer with a high resin content on the side of the resin layer 2, the layer with a high resin content adheres to the resin layer, and the layer with a high cement content adheres to a concrete structure. Adhesion to both is extremely excellent.

The polymer binder cured layer 3 is obtained by making a resin (resin component) containing a binder component into a paint, and then applying the paint. Examples of the above-mentioned cement component include various cements, limestones containing components composed of calcium oxide, clays containing silica, and the like. Among them, cement is preferred, for example, Portland cement, alumina cement, early-strength cement, fly ash cement and the like can be mentioned. Which cement to choose is selected according to the properties that the polymer cement hardened layer 3 should have, for example, the degree of followability to the concrete structure 21 is considered. In particular, Portland cement specified in JIS R5210 is preferable.

Examples of the aforementioned resin components include acrylic resins, acrylic urethane resins, acrylic silicone resins, fluororesins, flexible epoxy resins, polybutadiene rubbers, acrylic resins exhibiting rubber characteristics (for example, acrylate-based synthetic rubber), etc. From the viewpoint of improving the adhesion between the cured polymer cement layer 3 and the resin layer 2, it is preferable that the resin component is the same as the resin component constituting the resin layer 2 described later. In addition, any one of thermoplastic resins, thermosetting resins, and photocurable resins may be used as the above-mentioned resin component. The term "cured" in the cured polymer binder layer 3 does not mean that the resin component is limited to resins that polymerize after curing such as thermosetting resins or photocurable resins. Hardened material will do.

The content of the above-mentioned resin component can be appropriately adjusted according to the materials used, etc., but it is preferably 10% by weight or more and 40% by weight or less based on the total amount of the cement component and the resin component. If it is less than 10% by weight, the adhesiveness to the resin layer 2 decreases, and it becomes difficult to maintain the polymer binder hardened layer 3 as a layer. If it exceeds 40% by weight, the adhesiveness to the concrete structure 21 becomes insufficient. . From the above point of view, the content range of the above-mentioned resin component is preferably 15% by weight or more and 35% by weight or less, more preferably 20% by weight or more and 30% by weight or less.

The coating material for forming the polymer binder cured layer 3 is a coating solution obtained by mixing a binder component and a resin component with a solvent. As for the resin component, an emulsion is preferable. For example, an acrylic emulsion is polymer microparticles obtained by emulsifying monomers such as acrylate using an emulsifier. Acrylic polymer emulsion obtained by polymerizing more than one monomer or monomer mixture of ester is preferred. The content of acrylate and the like constituting the acrylic emulsion is not particularly limited, and can be selected from the range of 20 to 100% by mass. In addition, a surfactant may be added in an required amount, and the added amount is not particularly limited, and the surfactant may be added to the extent that it can form an emulsion.

The coating solution is coated on the release sheet, and then dried to remove the solvent (preferably water) to form the hardened polymer binder layer 3 . For example, a mixed composition of a binder component and an acrylic emulsion is used as a coating solution to form the polymer binder cured layer 3 . Although the resin layer 2 may be formed on the release sheet after the polymer adhesive hardened layer 3 is formed, it is also possible to form the polymer adhesive hardened layer 3 after the resin layer 2 is formed on the release sheet. Specifically, for example, apply a resin layer on engineering paper as a release sheet, apply a coating liquid for a polymer binder after drying, attach a Young's modulus adjustment layer in a wet state before drying, and then Let it dry. After that, further apply the coating solution for the polymer binder to the surface to which the Young's modulus adjustment layer is attached, and dry it to obtain the structure protection sheet of the present invention, wherein the Young's modulus adjustment layer exists on Polymer binder hardens the layer. In addition, the resin layer can be applied on the engineering paper as a release sheet, and the coating liquid for the polymer binder can be applied after drying, and the Young's modulus adjustment layer can be pasted in a wet state before drying, and then Without going through the drying step, the coating solution for the polymer binder is further coated on the surface to which the Young's modulus adjustment layer is attached, and then the whole is dried to obtain the structure protection sheet of the present invention, wherein Young's modulus The modulus adjustment layer is present in the hardened layer of polymer binder.

The thickness of the polymer cement hardened layer 3 is not particularly limited, and can be determined according to the use form of the structure 21 (such as river facilities such as roads and bridges, tunnels, and sluices, civil structures such as sewer ditches, harbor walls, etc.), degree of aging, shape, etc. Set it arbitrarily. As a specific thickness of the hardened polymer binder layer 3 , it may be in the range of 0.5 mm to 1.5 mm, for example. As an example, when the thickness is 1 mm, the thickness variation is preferably within ±100 μm. Such a precise thickness can never be achieved through on-site coating, but it can be achieved through stable coating on the factory's production line. Even thicker than 1 mm, the thickness variation can be within ±100 μm. In addition, in the case of being thinner than 1 mm, thickness variation can be further reduced.

Due to the presence of the binder component, the polymer binder cured layer 3 is more permeable to water vapor than the resin layer 2 described later. The water vapor transmission rate at this time is, for example, about 20 to 60 g/m ² ·day. Furthermore, the binder component has good compatibility with, for example, the binder component constituting concrete, and can have excellent adhesion to the concrete surface. In addition, as shown in Figure 2, when the primer layer 22 and the adhesive 23 are sequentially provided on the surface of the structure 21, the hardened polymer cement layer 3 containing the adhesive component and the adhesive 23 have good adhesion. sticky. Furthermore, since the polymer cement hardened layer 3 has extensibility, even if the structure 21 cracks or swells, it can follow changes in concrete.

(Young's modulus adjustment layer) Since the Young's modulus of the structure protection sheet 1 of the present invention can be adjusted to the above-mentioned range, it is preferable to provide the Young's modulus adjustment layer 5 in a state of being in contact with the hardened polymer cement layer 3 . Specifically, for example, the Young's modulus adjustment layer 5 may exist inside the polymer cement hardened layer 3 as shown in FIG. layer 3 and the surface in contact with resin layer 2 or the surface on the opposite side). Among them, the Young's modulus adjustment layer 5 is preferably embedded in the hardened polymer cement layer 3 . By embedding the Young's modulus adjusting layer 5 inside the hardened polymer cement layer 3, the contact area between the Young's modulus adjusting layer 5 and the hardened polymer cement layer 3 increases, and it is easier to make the adhesive strength of the two excellent , it is easier to ensure the overall strength of the polymer binder hardened layer 3 .

In the present invention, the Young's modulus adjustment layer 5 is preferably impregnated with a material (for example, a binder component or a resin component) constituting the polymer binder hardened layer 3 . The state in which the Young's modulus adjustment layer 5 is impregnated with the material constituting the polymer cement hardened layer 3 means that the material constituting the polymer cement hardened layer 3 is filled between the materials such as fibers constituting the Young's modulus adjustment layer 5 . The state of the material, through being in such an impregnated state, makes the adhesive strength between the Young's modulus adjusting layer 5 and the polymer binder hardened layer 3 easily become extremely excellent. In addition, the interaction between the materials of the Young's modulus adjustment layer 5 and the polymer cement cured layer 3 tends to become stronger, and the strength of the structure protection sheet 1 tends to become better.

The Young's modulus adjustment layer 5 is preferably at least one selected from the group consisting of a non-woven fabric layer, an elastic layer, a metal fiber layer, a particle dispersion layer, acicular and rod-shaped dispersion layers, and a mesh structure layer, wherein, The non-woven layer is also preferred. The nonwoven fabric constituting the nonwoven fabric layer is not particularly limited as long as it is a nonwoven fabric formed into a sheet without passing through the woven fibers. In addition, natural fibers and chemical fibers can be used as fibers constituting the nonwoven fabric. Examples of the above-mentioned chemical fibers include fibers made of polyolefin resins such as polypropylene and polyethylene, polyester resins, polyacrylic resins, polyamide resins such as nylon, and copolymers of these resins. materials, modified products, and synthetic fibers formed by combinations of the foregoing. Among them, polyester fibers having excellent water resistance, heat resistance, dimensional stability, weather resistance, etc. are preferable.

The basis weight of the above-mentioned nonwoven fabric is not particularly limited as long as it satisfies the above-mentioned Young's modulus, for example, it is preferably 5 g/m ² to 100 g/m ² , and 10 g/m ² or more. Below 50 g/m ² is better. When the basis weight of the nonwoven fabric is less than the above range, the nonwoven fabric becomes thin and cannot satisfy the above range of Young's modulus. Conversely, when the basis weight of the nonwoven fabric exceeds the above range, the structure protection sheet of the present invention 1 breathability may be reduced.

When viewed from the upper surface side of the polymer cement hardened layer 3, the size of the Young's modulus adjustment layer 5 may be the size covering the entire surface of the polymer cement hardened layer 3, or may be larger than the polymer cement hardened layer. Small. That is, the area of the Young's modulus adjustment layer 5 when viewed from above can be the same as the area of the hardened polymer cement layer 3 when viewed from above, or it can be smaller, but the area of the Young's modulus adjustment layer 5 when viewed from above is relatively smaller than that of the polymer cement hardened layer 3. The top view area of the cement hardened layer 3 is preferably more than 60%, more preferably more than 90%. If it is less than 60%, the structure protection sheet of the present invention may have insufficient strength, and may also vary in strength. The plan view area of the above-mentioned Young's modulus adjustment layer 5 and the like can be measured by a known method.

In addition, the Young's modulus adjusting layer 5 may be a uniform layer such as a grid shape, a staggered shape, a stripe shape, an island shape, or may be a layer irregularly provided at the crimped portion. When the Young's modulus adjustment layer 5 is a non-woven fabric layer by providing the crimping portion, it is possible to prevent aggregates of fibers from being scattered during the lamination process.

(resin layer) As shown in FIG. 2(C) , the resin layer 2 is arranged on the opposite side of the structure 21 and is a layer that appears on the surface. The resin layer 2 may be, for example, a single layer as shown in FIG. 1(A) or a laminate composed of at least two layers as shown in FIG. 1(B). Whether to form a single layer or multiple layers will be set in consideration of the overall thickness, the functions to be given (water resistance, salt barrier, neutralization prevention, water vapor permeability, etc.), the length of the factory production line, production costs, etc., for example, in When the production line is short and the predetermined thickness cannot be achieved with a single layer, it is possible to form a layer that is repeatedly coated with two or more layers. Overcoating is to coat the second layer after drying the first layer. Afterwards, the layer 2 is dried.

The resin layer 2 is obtained by coating a paint that can form a resin layer that has flexibility, can follow cracks or cracks that occur in concrete, and is excellent in water resistance, salt barrier properties, neutralization prevention properties, and water vapor permeability. of. Examples of the resin constituting the resin layer 2 include acrylic resins exhibiting rubber properties (for example, synthetic rubber containing acrylate as a main component), acrylic urethane resins, acrylic silicone resins, fluororesins, flexible epoxy resins, etc. Resin, polybutadiene rubber, etc. The resin material preferably has the same composition as the resin constituting the above-mentioned polymer cement layer 2 . In particular, a resin containing an elastic film forming component such as rubber is preferable.

Among them, the acrylic resin exhibiting rubber properties is preferably composed of an aqueous emulsion of an acrylic rubber copolymer from the viewpoint of excellent safety and coating properties. In addition, the proportion of the propylene-based rubber-based copolymer in the emulsion is, for example, 30 to 70% by mass. The acrylic rubber-based copolymer emulsion is obtained, for example, by emulsifying monomers in the presence of a surfactant. Any of anionic, nonionic, and cationic surfactants can be used.

The coating used to form the resin layer 2 is formed by preparing a mixed coating solution of a resin composition and a solvent, coating the coating solution on a release sheet, and then drying to remove the solvent to form the resin layer 2 . The solvent may be water or an aqueous solvent, or an organic solvent such as xylene or mineral spirits. In the examples described later, the resin layer 2 was produced from an acrylic rubber composition using an aqueous solvent. The order of layers formed on the release sheet is not limited, for example, it may be the above-mentioned sequence of resin layer 2, polymer binder hardened layer 3, or the order of polymer binder hardened layer 3, resin layer 2. However, as shown in the examples described later, it is better to form the resin layer 2 on the release sheet, and then form the hardened polymer adhesive layer 3 .

The thickness of the resin layer 2 can be arbitrarily set according to the use form of the structure 21 (such as river management facilities such as roads and bridges, tunnels, and sluices, civil structures such as sewer ditches, harbor walls, etc.), aging degree, shape, etc. As an example, if the thickness is in the range of 50 to 150 μm, the thickness deviation is preferably within ±50 μm. Such a precise thickness cannot be achieved through on-site coating, but it can be achieved stably through the factory's production line.

The resin layer 2 has high water resistance, salt-shielding properties, and neutralization prevention properties, but is preferably permeable to water vapor. The water vapor transmission rate at this time is, for example, preferably about 10 to 50 g/m ² ·day. Thereby, the structure protection sheet 1 can be provided with high water repellency, salt-blocking property, neutralization preventing property, and predetermined water vapor permeability. Furthermore, since it is composed of the same resin component as the polymer cement hardened layer 3 , it can have good compatibility with the polymer cement hardened layer 3 and have excellent adhesion. The water vapor permeability was measured according to JIS Z0208 "Test method for moisture permeability of moisture-proof packaging materials".

In addition, the resin layer 2 may contain a pigment from the viewpoint of enriching the color variation of the structure protection sheet 1 of the present invention. In addition, the resin layer 2 may contain inorganic substances. By containing an inorganic substance, scratch resistance can be imparted to the resin layer 2 . It does not specifically limit as said inorganic substance, For example, a conventionally well-known material, such as metal oxide particle|grains of silicon dioxide, aluminum oxide, and titanium dioxide, is mentioned. Further, the resin layer 2 may contain a known antifouling agent. Since the structure protection sheet of the present invention is usually used for repairing concrete structures placed outdoors, the resin layer 2 is often polluted, and the structure protection sheet of the present invention can be properly prevented from being polluted by containing an antifouling agent. The above-mentioned antifouling agent is not particularly limited, and conventionally known materials can be mentioned. In addition, the resin layer 2 may contain additives capable of imparting various functions. Examples of such additives include cellulose nanofibers and the like.

(Other configurations) The finished structure protection sheet 1 may be provided with a release sheet on one surface of the polymer adhesive hardened layer 3 and the resin layer 2 . For example, the release sheet can protect the surface of the structure protection sheet 1 when going to the construction site. Layer 22 or adhesive 23), and then easily peel off the release sheet, greatly improving the workability of the construction site. The release sheet is preferably the engineering paper utilized in the production steps of the structure protection sheet 1 .

The engineering paper used as the release sheet is not particularly limited as long as it is a conventionally known one used in the production process. For example, laminated paper, etc. which have an olefin resin layer, such as polypropylene and polyethylene, or a layer containing silicon, is mentioned like the well-known engineering paper. The thickness is not particularly limited, and can be any thickness as long as it does not interfere with manufacturing and construction handling, for example, about 50 to 500 μm.

The structure protection sheet 1 described above can protect structures 21 such as concrete for a long period of time. In particular, the structure protection sheet 1 is endowed with performance corresponding to the characteristics of the structure 21, can follow the cracks or swelling that appear in the structure 21, prevents deterioration factors such as water and chlorine ions from penetrating into the structure 21, and has the function of Permeable to the discharge of moisture in the structure, deterioration factors, and can be properly stretched when attached to the structure, so as to prevent tearing or permanent deformation. Since such a structure protection sheet 1 can be manufactured in a factory, a high-quality product having stable characteristics can be mass-produced. As a result, construction can be performed without relying on the skills of craftsmen, shortening the construction period, and reducing labor costs.

[Manufacturing method of reinforced structure using structure protection sheet] As shown in FIG. 2 , the method of manufacturing a reinforced structure using the structure protection sheet of the present invention is the construction method used in the above structure protection sheet 1 of the present invention, and is characterized in that the adhesive 23 is applied to After the structure 21 is placed, the structure protection sheet 1 is attached. This construction method can easily attach the structure protection sheet 1 to the surface of the structure 21 . As a result, even an unskilled worker can install the structure protection sheet 1 made of layers with little variation in thickness on the structure 21 , and can protect the structure 21 for a long period of time while significantly shortening the construction period.

Fig. 2 is an explanatory diagram of the construction method of the structure protection sheet 1 (the method of manufacturing the reinforced structure). As shown in FIG. 2(A), the primer layer 22 is formed on the surface of the structure 21 . The undercoat layer 22 can be formed by applying a coating solution obtained by mixing a resin such as an epoxy resin and a solvent onto the structure 21, and then evaporating the solvent in the coating solution and drying it. As a solvent in this case, the same water etc. as mentioned above are mentioned. The thickness of the undercoat layer 22 is not particularly limited, and may be, for example, within a range of 100-150 μm. Since the primer layer 22 disposed between the structure 21 and the adhesive 23 plays a role of improving mutual adhesion, the structure protection sheet 1 can stably protect the structure 21 for a long time. When the structure 21 has a crack, a chip, etc., it is preferable to provide the primer layer 22 after repairing it. In addition, repairing is not particularly limited, and cement mortar, epoxy resin, and the like are usually used.

After the undercoat layer 22 is formed, as shown in FIG. 2(B), an adhesive 23 is applied. As shown in FIG. 2(C) , the structure protection sheet 1 is attached thereto without drying the applied adhesive 23 . Examples of the adhesive 23 include urethane-based adhesives, epoxy-based adhesives, and adhesives using acrylic resin (for example, synthetic rubber mainly composed of acrylate) exhibiting rubber properties. Among them, the adhesive 23 composed of the same resin component as the resin component of the polymer adhesive hardened layer 3 constituting the structure protection sheet 1 is preferable because the adhesive strength between the polymer adhesive hardened layer 3 and the polymer adhesive hardened layer 3 is high. The thickness of the adhesive 23 is not particularly limited. Usually, the adhesive 23 is applied to the concrete by brushing or spraying, and then allowed to dry and harden naturally over time.

Fig. 3 is an explanatory diagram of an example of applying the structure protection sheet 1 to the cast-in-place method. The cast-in-place method is a method in which a mold 24 is formed at a work site, a concrete composition 21' is poured into the mold 24, and left to harden to obtain a concrete structure 21. In this cast-in-place method, after the hardened concrete structure 21 is formed, the structure protection sheet 1 is bonded to the surface to obtain a structure 21 that is less likely to deteriorate. When pasting, apply the primer layer 22 on the surface of the concrete structure 21 and dry it, then apply the adhesive 23 thereon, and then paste the structure protection sheet 1 . Afterwards, the adhesive 23 is usually left to dry and harden, thereby bonding the structure protection sheet 1 .

On the other hand, for the structure 21 where cracks or the like have already occurred, after the missing part is repaired, the structure protection sheet 1 is bonded by the same construction method as above. Therefore, the lifetime of the concrete structure 21 can be extended.

[Example] The present invention will be explained more specifically through examples and comparative examples.

(Example 1) A 130 μm-thick release sheet made of PP laminated paper was used. Form the resin layer on the release sheet by the following method. First, an emulsion composition containing 60 parts by mass of an acrylic silicone resin, 25 parts by mass of titanium dioxide, 10 parts by mass of iron oxide, and 5 parts by mass of carbon black was prepared. After coating the emulsion composition on the release sheet, it is cured by heat treatment to form a resin layer. The thickness of the resin layer was set to 0.1 mm. Next, a hardened layer of polymer binder is formed on the resin layer. Specifically, an aqueous acrylic emulsion containing 45 parts by mass of the binder mixture was prepared as a composition for forming a polymer binder layer. Here, the cement mixture contains at least 70 ± 5 parts by mass of Portland cement, 10 ± 5 parts by mass of silica, 2 ± 1 parts by mass of alumina, 1 to 2 parts by mass of titanium dioxide, and acrylic acid emulsified The liquid contains at least 53±2 parts by mass of an acrylic polymer obtained by emulsion polymerization using an acrylate monomer as an emulsifier, and 43±2 parts by mass of water. The cured polymer binder layer obtained by applying and drying the polymer binder layer-forming composition mixed with these is a composite layer containing 50% by mass of Portland binder in acrylic resin. After applying the composition for forming a cured layer of a polymer binder on the resin layer so that the thickness before drying is 1.0 mm, a Young's modulus of polyester nonwoven fabric with a basis weight of 12 g/ ^m2 is set. Adjustment layer. Next, on this Young's modulus adjusting layer, the composition for forming the above-mentioned polymer binder cured layer was further coated on the resin layer so that the thickness before drying was 1.0 mm, and then dried to form a thickness of 1.0 mm. 1.29 mm hardened layer of polymer binder3. Thus, a structure protection sheet having a total thickness of 1.39 mm was produced. In addition, this structure protection sheet is continuously produced in a factory controlled at about 25° C., and wound into a roll in a state including a release sheet.

[Measurement of Young's modulus] The Young's modulus of the structure protection sheet 1 obtained in Example 1 was measured using a tensile tester (AGX-V, manufactured by Shimadzu Corporation). The Young's modulus of Example 1 is 20 MPa. The structure protection sheet 1 of Example 1 has excellent strength, maintains proper elasticity when attached to structures, is convenient for construction operations, and will not tear or permanently deform. [Measurement of thickness variation] Regarding Example 1, about A4 size (200 mm × 300 mm) was cut out from the structure protection sheet 1 wound in a roll, and the thickness was measured at 14 places at each location to calculate the variation in thickness. In Example 1, the thickness variation was 26 μm.

(Examples 2 and 3) As the Young's modulus adjustment layer, except for the Young's modulus adjustment layer (Example 2) made of a nonwoven fabric made of polyester with a basis weight of 20 g/m ² , the basis weight Non-woven fabrics made of polyester non-woven fabrics of 50 g/ ^m2 , Young's modulus adjustment layers provided with pressure-bonding parts by pressing with a metal roll with a surface temperature of 80°C (Example 3) , and produced the structure protection sheet 1 in the same manner as in Example 1.

(comparative example 1) Fabricate the structure protection in the same manner as in Example 1, except that a network layer made of aramid fibers with a density of 1.0 strands/cm and a pitch of 10 mm is provided instead of the Young's modulus adjustment layer. piece.

(comparative example 2) Except not having provided the Young's modulus adjustment layer, it carried out similarly to Example 1, and produced the structure protection sheet.

[Measurement of Young's modulus] The Young's modulus of the structure protection sheets of Example 2, Example 3, Comparative Example 1, and Comparative Example 2 were measured in the same manner as in Example 1. Example 2 is 50 MPa, Example 3 is 250 MPa, Comparative Example 1 is 10 MPa, and Comparative Example 2 is 500 MPa. The structure protection sheet of the example has excellent strength and will not tear or permanently deform when attached to the structure, but the structure protection sheet of Comparative Example 1 has poor strength and will tear or permanently deform when attached to the structure , The structure protection sheet of Comparative Example 2 was too rigid and could not be stretched sufficiently when attached to the structure.

1: Structure protection sheet 2: resin layer 3: Polymer binder hardened layer 5: Young's modulus adjustment layer 21: Structure (concrete) 21': Concrete composition (structure forming composition) 22: Base coat 23: Adhesive 24: Mold

Fig. 1 is a cross-sectional structural view of an example of the structure protection sheet of the present invention. Fig. 2 is an explanatory diagram of a construction method of a structure protection sheet. Fig. 3 is an explanatory diagram of an example of applying a structure protection sheet to a cast-in-place method.

1: Structure protection sheet

2: resin layer

3: Polymer binder hardened layer

5: Young's modulus adjustment layer

Claims (7)

A structure protection sheet, which is a structure protection sheet provided with a polymer adhesive hardened layer arranged on the structure side and a resin layer arranged on the polymer adhesive hardened layer, characterized in that the Young's modulus is 20 ~300MPa. The structure protection sheet according to Claim 1 has a Young's modulus of 10 to 300 MPa in the range where the stress is 2.0 MPa or less and the elongation is 5% or less. The structure protection sheet according to claim 1 or 2, which has a Young's modulus adjustment layer in contact with the hardened polymer cement layer. The structure protection sheet as described in claim 3, the Young's modulus adjustment layer is selected from non-woven fabric layer, elastic layer, metal fiber layer, particle dispersion layer, needle-shaped and rod-shaped dispersion layer, mesh structure layer At least one of the group of . In the structure protection sheet according to claim 1, 2, 3, or 4, the polymer binder hardened layer is a layer containing a binder component and a resin, and the content of the resin is not less than 10% by weight and not more than 40% by weight. A method of manufacturing a reinforced structure, which is a method of manufacturing a reinforced structure using the structure protection sheet as described in claim 1, 2, 3, 4 or 5, characterized in that the adhesive is coated Attach the structure protection sheet after cloth is placed on the structure. In the method of manufacturing a reinforced structure according to claim 6, a primer layer is provided between the structure and the adhesive.

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