JP2011208352A - Method for reinforcing structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for reinforcing a structure, which has merits in the use of a fiber-reinforced sheet, which enables firm adhesion to a binding material, when an inorganic binding material made of a cement-based material is used as the binding material, and which can avoid the separation of the fiber-reinforced sheet from the cement material before the fiber-reinforced sheet reaches fracture strength.SOLUTION: In the fiber-reinforced sheet 1, a plurality of continuous fiber-reinforced plastic wire rods, in which a reinforcing fiber is impregnated with a matrix resin and hardened, are longitudinally pulled and aligned like a bamboo blind, and fixed to one another by means of a wire rod fixing material. After being coated with an adhesive for a coating joint, the fiber-reinforced sheet 1 is bonded to a surface of the structure 100 before the hardening of the adhesive; and cement mortar, polymer cement mortar, cement paste, polymer cement paste or the inorganic binding material made of concrete is placed as the binding material.

Description

  The present invention uses a fiber reinforced sheet to make a concrete structure or a steel structure, which is a civil engineering building structure, a wooden structure, a plastic structure, or a composite structure thereof (in this specification, , A concrete structure, a steel structure, a wooden structure, a plastic structure, and a composite structure thereof are simply referred to as “structures”).

  In recent years, a continuous reinforcing fiber sheet such as a carbon fiber sheet or an aramid fiber sheet is pasted or wound around the surface of a structure as described in Patent Document 1 as a method for reinforcing an existing or new structure. There are continuous fiber sheet bonding methods such as a carbon fiber sheet bonding method and an aramid fiber sheet bonding method, or a method in which a sheet obtained by impregnating a continuous fiber bundle with an uncured matrix resin is bonded and cured.

  Furthermore, in order to omit the resin impregnation on site, a FRP plate adhesion reinforcing method has been developed in which a factory-produced FRP plate having a thickness of 1 to 2 mm and a width of about 5 cm is adhered to the concrete surface using a putty-like adhesive resin.

  However, the above continuous fiber sheet bonding method requires time and effort to impregnate the reinforcing fiber bundle with the matrix resin in order to adhere the matrix resin (impregnation adhesive) to the reinforcing structure while impregnating the continuous fiber sheet with the construction site. However, there is a drawback that poor quality due to local construction such as poor matrix resin impregnation, swollen continuous fiber sheet, and floating is likely to occur.

  In addition, since the continuous fiber of the fiber sheet is impregnated with resin at the construction site, if the fiber basis weight of the fiber sheet is increased, the impregnation adhesive does not impregnate into the fiber bundle, and the low-viscosity matrix resin for impregnation Is used as an adhesive resin for the structure, and if the fiber sheet is too heavy, the continuous fiber sheet may be peeled off and dropped before the adhesive resin is cured.

For this reason, it is difficult to increase the fiber basis weight of the continuous fiber sheet, and the limit is about 600 g / m ^{2 in} the case of the carbon fiber sheet.

  For this reason, when the required amount of reinforcement is large, it is necessary to laminate multiple layers, and there are disadvantages such as a long construction period and high costs.

  Further, for example, the surface of the concrete structure after the ground treatment has air bubbles in the concrete exposed in a burrow shape on the surface, and has irregularities such as a mold step. When the sheet is directly adhered to the concrete surface using an impregnation adhesive of a low viscosity resin (viscosity 40,000 mPa · sec or less) for impregnating the fiber bundle of the continuous fiber sheet, the sheet is made to follow the step shape. The sheet cannot be fixed, causing floating, and poor construction such as expansion of the sheet due to expansion of air in the burrow-shaped bubbles.

  For this reason, it is necessary to apply a non-land surface correction material such as an epoxy resin putty to the concrete surface and smooth it by trowel finish, and after the non-land surface correction material is cured, it is necessary to apply an impregnation adhesive for sheet bonding again. There were problems such as construction period and high cost.

  In addition, the method of curing after adhering a sheet in which a continuous fiber bundle is impregnated with the uncured matrix resin is a continuous fiber sheet impregnated with resin. There was a drawback that quality defects were liable to occur due to on-site construction such as sheet swelling and floating.

  Furthermore, the FRP plate bonding reinforcement method of bonding an FRP plate having a plate thickness of 1 to 2 mm and a width of about 5 cm to a concrete surface using a putty-like adhesive resin is difficult to cover and cover the entire structure with a small plate width. It was difficult to apply to surface members such as floor slabs.

  In addition, since the FRP plate, which is thicker than the continuous fiber sheet thickness of about 0.1 mm to 0.5 mm, is partially bonded in a strip shape, the bonding area is extremely small compared to the continuous fiber sheet bonding method. There is a drawback that peeling is likely to occur from the end due to the concentration of the adhesion shear stress acting on the surface.

  Furthermore, because the plate thickness is thick, the lap joint made of adhesive peels off the joint before reaching the tensile strength of the FRP plate, so the lap joint cannot be used and one FRP plate over the entire length of the reinforcement range. There is a problem in workability with long structures.

  Therefore, in Patent Document 2, fibers in which reinforcing fibers are impregnated with a matrix resin and cured are continuously arranged in a plurality of continuous fiber reinforced plastic wire materials in a slender shape in the longitudinal direction, and the wire materials are fixed to each other with a wire material fixing material. There has been proposed a method for reinforcing a structure in which a reinforcing sheet is bonded to and integrated with the surface of the structure with a binder.

  This method of reinforcing a structure does not require on-site impregnation of the resin into the fiber bundle constituting the fiber reinforced sheet, and there is no risk of poor impregnation, and can provide a method of reinforcing the structure with high work efficiency. .

  In particular, when an inorganic cement-based material is used as a binder, the cement member is resistant to fire and does not burn. Therefore, a fiber reinforced sheet effective for reinforcement can be protected from fire and treated as a non-combustible material. Has an advantage.

JP-A-3-224901 JP 2008-63758 A

  However, as a result of the research experiment of the present inventors, in the reinforcing method described in Patent Document 2, the fiber reinforced sheet to be used is an organic material in which the resin impregnated in the strand has been cured. In particular, when an inorganic cement material is used as the binder, it has been found that adhesion with the binder is difficult. In some cases, the fiber reinforced sheet peeled off from the cement material before reaching the breaking strength.

  Therefore, the object of the present invention is to have the advantage when using a fiber reinforced sheet, and when using an inorganic binding material, which is a cement-based material, as a binding material, extremely strong adhesion to the binding material. It is an object of the present invention to provide a method for reinforcing a structure, which can prevent the fiber-reinforced sheet from being peeled off from the cement material before reaching the breaking strength.

The above object is achieved by the method for reinforcing a structure according to the present invention. In summary, according to the first aspect of the present invention, a plurality of continuous fiber reinforced plastic wires that have been impregnated with a matrix resin in a reinforcing fiber and are cured are arranged in a slender shape in the longitudinal direction, and the wires are mutually fixed as a wire fixing material. In the method of reinforcing a structure in which the fiber reinforced sheet fixed in place is bonded to the surface of the structure with a binder and integrated,
(A) a step of grounding the surface of the structure;
(B) An inorganic bond in which a joint adhesive is applied to the surface of the surface-treated structure and then cement mortar, polymer cement mortar, cement paste, polymer cement paste, or concrete is used as a binder. The process of placing the material,
(C) The structure is obtained by pressing the fiber-reinforced sheet coated with a joint adhesive on the inorganic binding material placed in the step (b) before the joint adhesive is cured. Adhering to the surface of objects,
(D) A step of placing an inorganic binding material as cement mortar, polymer cement mortar, cement paste, polymer cement paste, or concrete as a binder on the surface of the structure to which the fiber reinforced sheet is bonded. ,
A method for reinforcing a structure is provided.

According to the second aspect of the present invention, a plurality of continuous fiber reinforced plastic wires that are impregnated with a matrix resin in a reinforced fiber and hardened are arranged in a slender shape in the longitudinal direction, and the wires are fixed to each other with a wire fixing material. In the reinforcing method of the structure in which the reinforcing sheet is bonded to the surface of the structure with a binder and integrated,
(A) a step of grounding the surface of the structure;
(B) An inorganic bond in which a joint adhesive is applied to the surface of the surface-treated structure and then cement mortar, polymer cement mortar, cement paste, polymer cement paste, or concrete is used as a binder. The process of placing the material,
(C) A step of applying an adhesive for coating on the inorganic binding material placed in the step (b),
(D) a step of pressing the fiber reinforced sheet and adhering it to the surface of the structure before the coating adhesive applied in the step (c) is cured;
(E) placing a cement mortar, a polymer cement mortar, a cement paste, a polymer cement paste, or an inorganic binder as concrete on the surface of the structure to which the fiber reinforced sheet is bonded ,
A method for reinforcing a structure is provided.

According to the third aspect of the present invention, fibers in which reinforcing fibers are impregnated with a matrix resin and cured are continuously arranged in a plurality of continuous fiber-reinforced plastic wire rods in a longitudinal direction, and the wire rods are fixed to each other with a wire rod fixing material. In the reinforcing method of the structure in which the reinforcing sheet is bonded to the surface of the structure with a binder and integrated,
(A) a step of grounding the surface of the structure;
(B) a step of pressing the fiber-reinforced sheet coated with a joint adhesive on the surface of the structure subjected to the base treatment and bonding the fiber reinforced sheet to the surface of the structure before the joint adhesive is cured;
(C) Placing an inorganic binding material to be cement mortar, polymer cement mortar, cement paste, polymer cement paste, or concrete as a binder on the surface of the structure to which the fiber reinforced sheet is bonded. ,
A method for reinforcing a structure is provided.

According to the fourth aspect of the present invention, fibers in which reinforcing fibers are impregnated with a matrix resin and cured are continuously arranged in a plurality of continuous fiber-reinforced plastic wire rods in the longitudinal direction, and the wire rods are fixed to each other with a wire rod fixing material. In the reinforcing method of the structure in which the reinforcing sheet is bonded to the surface of the structure with a binder and integrated,
(A) a step of grounding the surface of the structure;
(B) applying a coating adhesive to the surface of the structure subjected to the ground treatment;
(C) before the adhesive for coating applied in the step (b) is cured, the step of pressing the fiber reinforced sheet to adhere to the surface of the structure;
(D) A step of placing an inorganic binding material as cement mortar, polymer cement mortar, cement paste, polymer cement paste, or concrete as a binder on the surface of the structure to which the fiber reinforced sheet is bonded. ,
A method for reinforcing a structure is provided.

  According to one embodiment of the present invention, a primer is applied to the surface of the structure subjected to the ground treatment in the step (a), and the step (b) is performed after the primer is cured.

  According to another embodiment of the present invention, the fiber reinforced sheet is laminated and adhered to the surface of the structure in a plurality of layers, and is integrated with the structure.

  According to another embodiment of the present invention, the reinforcing fiber of the fiber reinforced plastic wire may be carbon fiber, glass fiber, basalt fiber; metal fiber such as boron fiber, titanium fiber, steel fiber; aramid, PBO (polyparaphenylene benz). Organic fibers such as bisoxazole), polyamide, polyarylate, and polyester are used alone or in a mixture of plural kinds.

  According to another embodiment of the present invention, the matrix resin of the fiber reinforced plastic wire is a room temperature curing type or thermosetting type epoxy resin, vinyl ester resin, MMA resin, acrylic resin, unsaturated polyester resin, or phenol resin. Or a thermoplastic resin such as nylon or vinylon.

According to another embodiment of the invention, the adhesive for splicing is
(1) Room temperature curable epoxy resin, acrylic resin, styrene resin, vinyl acetate resin, styrene butadiene resin, or
(2) an emulsion of each of the above resins, or
(3) a mixture of two or more of the above resins or resin emulsions,
It is. Preferably, the adhesive for jointing has a viscosity in the range of 100 to 200,000 mPa · sec at 23 ° C. and a thixotropic index in the range of 1 to 8.

  According to another embodiment of the present invention, the inorganic binding material is mixed with a fiber material.

  According to another embodiment of the present invention, the fiber reinforced plastic wire has a circular cross-sectional shape with a diameter of 0.5 to 3 mm, or a width of 1 to 10 mm and a thickness of 0.1 to 2 mm. It has a rectangular cross-sectional shape.

  According to another embodiment of the present invention, the fiber reinforced plastic wires are separated from each other by 0.05 to 3.0 mm.

  According to another embodiment of the present invention, the fiber reinforced sheet has a width of 100 mm to 10 m.

  According to the method for reinforcing a structure of the present invention, a fiber reinforced sheet that does not require in-situ impregnation of resin into the fiber bundle constituting the fiber reinforced sheet, does not cause impregnation failure, and has high work efficiency is used. When using an inorganic bonding material, which is a cement-based material as a bonding material, the adhesion with the bonding material can be bonded extremely firmly, before the fiber reinforced sheet reaches the breaking strength. It is possible to avoid peeling from the cement material.

It is a perspective view which shows one Example of the fiber reinforced sheet which can be used for the reinforcement method of the structure of this invention. It is sectional drawing of the fiber reinforced plastic wire which comprises the fiber reinforced sheet which can be used for the reinforcing method of the structure of this invention. It is a perspective view which shows the other Example of the fiber reinforced sheet which can be used for the reinforcing method of the structure of this invention. It is a figure which shows the other Example of the fiber reinforced sheet which can be used for the reinforcement method of the structure of this invention. It is a figure which shows the other Example of the fiber reinforced sheet which can be used for the reinforcement method of the structure of this invention. It is process drawing explaining one Example of the reinforcement method of the structure of this invention. It is process drawing explaining the other Example of the reinforcement method of the structure of this invention. It is a figure explaining the structure of the test piece used for the bending strength test for demonstrating the reinforcement method of the structure of this invention.

  Hereinafter, the method for reinforcing a structure according to the present invention will be described in more detail with reference to the drawings.

Example 1
(Fiber reinforced sheet)
1 and 2 show an embodiment of a fiber reinforced sheet 1 used in the method for reinforcing a structure according to the present invention. The fiber reinforced sheet 1 is formed by arranging a plurality of continuous fiber reinforced plastic wires 2 in a slender shape in the longitudinal direction, and the wires 2 are fixed to each other by a wire fixing material 3.

  The fiber reinforced plastic wire 2 has an elongated shape (small diameter) in which a matrix resin R is impregnated with a plurality of continuous reinforcing fibers f oriented in one direction and cured, and has elasticity. Accordingly, the fiber reinforced sheet 1 in which the elastic fiber reinforced plastic wire 2 is formed in a sled shape, that is, a sheet shape in which the wires 2 are arranged close to and away from each other, has elasticity in its longitudinal direction. Yes. Therefore, for example, the long fiber reinforced sheet 1 can be carried in a state of being wound at a predetermined radius during conveyance, and is extremely portable. In addition, since the fiber reinforced sheet 1 is composed of the fiber reinforced plastic wire 2, there is a concern that the orientation of the reinforcing fibers is disturbed or the yarn breakage occurs during conveyance as in a conventional unimpregnated reinforced fiber sheet. There is no.

  More specifically, the thin fiber reinforced plastic wire 2 has a substantially circular cross-sectional shape (FIG. 2A) having a diameter (d) of 0.5 to 3 mm, or a width (w) of 1 to 10 mm. , And a substantially rectangular cross-sectional shape (FIG. 2B) having a thickness (t) of 0.1 to 2 mm. Of course, other various cross-sectional shapes can be used as necessary. Moreover, in order to improve the adhesive force at the time of use, the fiber reinforced plastic wire 2 is preferably roughened by roughening the surface using shot blasting, a gold brush, or the like.

  As described above, in the fiber reinforced sheet 1 that is aligned and slid in one direction, the wires 2 are close to and separated from each other by a gap (g) = 0.05 to 3.0 mm to the wire fixing material 3. Fixed. In addition, the length (L) and width (W) of the fiber reinforced sheet 1 formed in this way are appropriately determined according to the size and shape of the structure to be reinforced, Generally, the total width (W) is 100 to 1000 mm. Moreover, although the length (L) can manufacture a strip-shaped thing about 1-5 m, or a thing 100 m or more, it cuts and uses it suitably at the time of use.

  It is also possible to manufacture the fiber-reinforced sheet 1 with a length (L) of about 1 to 5 m and a width W of about 1 to 10 m. In this case, the fiber reinforced plastic wire 2 can be wound in a direction perpendicular to the fiber reinforced plastic wire 2 in a stretched state, and can be wound and conveyed.

  As the reinforcing fiber f, carbon fiber, glass fiber, basalt fiber; metal fiber such as boron fiber, titanium fiber, steel fiber; and further, aramid, PBO (polyparaphenylene benzbisoxazole), polyamide, polyarylate, polyester, etc. These organic fibers can be used alone or in a hybrid mixed with a plurality of types.

  The matrix resin R impregnated in the fiber reinforced plastic wire 2 can be a thermosetting resin or a thermoplastic resin. As the thermosetting resin, a room temperature curing type or a thermosetting type epoxy resin, vinyl ester can be used. Resin, MMA resin, acrylic resin, unsaturated polyester resin, phenol resin, or the like is suitably used, and nylon, vinylon, or the like can be suitably used as the thermoplastic resin. The resin impregnation amount is 30 to 70% by weight, preferably 40 to 60% by weight.

  Further, as a method of fixing each wire 2 with the wire fixing material 3, as shown in FIG. 1, for example, a plurality of wires arranged in a sag-like manner using wefts as the wire fixing material 3 are arranged. It is possible to adopt a method of driving and knitting a wire rod in the form of a sheet consisting of two, that is, a continuous wire rod sheet at a constant interval (P) perpendicular to the wire rod. The driving interval (P) of the weft yarn 3 is not particularly limited, but is usually selected in the range of 10 to 100 mm in consideration of the handleability of the produced fiber reinforced sheet 1.

  At this time, the weft 3 is, for example, a yarn obtained by bundling a plurality of glass fibers or organic fibers having a diameter of 2 to 50 μm. Moreover, nylon, vinylon, etc. are used suitably as an organic fiber.

  As another method of fixing each wire 2 in a slender shape, a mesh-like support sheet can be used as the wire fixing member 3 as shown in FIG.

  In other words, a plurality of wire rods 2 arranged in the form of a sheet form, that is, one side or both sides of the wire sheet is made of, for example, a glass fiber or organic fiber having a diameter of 2 to 50 μm. It can also be set as the structure supported by the body sheet | seat 3. FIG.

  In this case, for example, the surface of the warp yarn 4 and the weft yarn 5 constituting the biaxially configured mesh-like support sheet 3 is impregnated in advance with a low melting point type thermoplastic resin, and the mesh-like support sheet 3 Are laminated on both sides of the suede-like wire sheet and heated and pressed to weld the warp 4 and weft 5 parts of the mesh-like support sheet 3 to the suede-like wire sheet.

  In addition to the biaxial configuration, the mesh-like support sheet 3 is formed by orienting glass fibers in three axes, or only the wefts 5 that are orthogonal to the wire 2 are disposed. It can also be bonded to a plurality of wire rods 2 formed so as to be oriented in the axis and aligned in the form of a sheet.

  As the yarn of the wire fixing material 3, for example, a double-structured composite fiber having a glass fiber in the core and a low-melting-point heat-fusible polyester around it is also preferably used. .

  Furthermore, as another method of fixing each wire 2 in a slender shape, as shown in FIG. 3 (b), as the wire fixing material 3, for example, a flexible belt material such as an adhesive tape or an adhesive tape is used. Can be used. The flexible strip 3 has one side or both sides of a plurality of fiber reinforced plastic wires 2 in a direction perpendicular to the longitudinal direction of each fiber reinforced plastic wire 2 arranged in the form of a sheet. Paste and fix.

  That is, as the flexible strip 3, an adhesive tape or adhesive tape such as a vinyl chloride tape, a paper tape, a cloth tape, and a nonwoven fabric tape having a width (w1) of about 2 to 30 mm is used. These tapes 3 are usually stuck in a direction perpendicular to the longitudinal direction of each fiber reinforced plastic wire 2 at intervals (P) of 10 to 100 mm.

  Furthermore, as the flexible strip 3, the thermoplastic resin such as nylon or EVA resin is formed into a strip and is heat-bonded to one side or both sides in the direction perpendicular to the longitudinal direction of the wire 2. Is done.

  Furthermore, it can also be set as the woven fiber reinforcement sheet by a loom system.

That is, as shown in FIG.
(A) As warps, a plurality of continuous fiber reinforced plastic wires 2 are arranged in parallel with a predetermined g gap between them, and auxiliary warps 5 are arranged between the fiber reinforced plastic wires 2 arranged in parallel. Arranged in parallel at a predetermined interval P0,
(B) Along the longitudinal direction of the fiber reinforced plastic wire 2 so as to be located on either side of the sheet-like fiber reinforced plastic wire formed by a plurality of fiber reinforced plastic wires 2 arranged in parallel. The weft yarns 3 are arranged at a predetermined interval P, and the weft yarns 3 are woven into the warp yarns 2 and the auxiliary warp yarns 5, thereby fixing a plurality of fiber reinforced plastic wire rods 2 arranged in parallel in a sheet shape.
It is produced by.

Furthermore, as shown in FIG.
(A) As warps, a plurality of continuous fiber reinforced plastic wires 2 are arranged in parallel with each other having a predetermined gap g;
(B) For the plurality of fiber reinforced plastic wires 2 arranged in parallel to each other, wefts 3 are woven at predetermined intervals along the longitudinal direction of the fiber reinforced plastic wire 2, and a sheet-like woven fabric is woven.
It is produced by.

(Reinforcing method)
Next, a method for reinforcing a structure will be described with reference to FIGS. According to the present invention, the structure 100 is reinforced using the fiber reinforced sheet 1 manufactured as described above.

  That is, according to the method for reinforcing a structure of the present invention, a plurality of continuous fiber reinforced plastic wires 2 in which reinforcing fibers f are impregnated with matrix resin R and hardened are arranged in a slender shape in the longitudinal direction. Are bonded to the surface of the structure 100 with a bonding material 104 and integrated.

  When reinforcing a structure, for a member (structure) that mainly receives bending moment and axial force, the direction of the fiber reinforced plastic wire 2 is made to substantially coincide with the principal stress direction of tensile stress or compression stress generated by the bending moment. By bonding, the fiber reinforced sheet 1 effectively bears stress, and can efficiently improve the load resistance of the structure.

  When a bending moment acts in two orthogonal directions such as a two-way slab, the two or more layers of fiber reinforced sheets 1 are orthogonal so that the direction of the fiber reinforced plastic wire 2 substantially coincides with the principal stress generated by the bending moment. By carrying out laminating and bonding, load resistance can be improved efficiently.

  When the reinforcing target structure is a concrete member such as reinforced concrete or unreinforced concrete and is a bar member that receives a shearing force, the fiber reinforced sheet 1 is bonded to the side surface of the bar.

  In the following examples, a concrete structure will be described as an example of the structure, but the present invention is not limited to a concrete structure as a structure to be reinforced, a steel structure, The present invention can also be suitably applied to a wooden structure, a plastic structure, or a composite structure thereof.

(First step)
As shown in FIGS. 6A and 6B, the weakened portion 101a of the surface to be reinforced (that is, the surface to be bonded) 101 of the concrete structure 100 is ground with a disk sander, sand blast, steel shot blast, water jet or the like. The substrate 50 is removed by means 50, and the surface to be bonded 101 of the structure 100 is treated so as to be a surface 102 having an appropriate roughness.

(Second step)
An epoxy resin primer 103 or the like is applied to the surface 102 subjected to the ground treatment (FIG. 6C). The primer 103 is not limited to an epoxy resin, but includes a MMA resin, a vinyl acetate emulsion, an SBR emulsion, an acrylic emulsion, a styrene-acrylic copolymer emulsion, an aqueous resin, and the like. It is appropriately selected according to the material of the reinforcing structure 100.

  In addition, the application | coating process of the primer 103 can also be skipped.

(Third step)
In the case where the primer 103 is applied, after the primer 103 is cured, the coating adhesive 105 is applied (FIG. 6D). Next, preferably, before the coating adhesive is cured, the bonding material 104 is cast in a required thickness (T) (FIG. 6E). The casting thickness (T) is appropriately set according to the unevenness of the surface of the adherend surface 102 and the thickness of the fiber reinforced sheet 1, but is generally about 2 to 10 mm.

Various adhesives or resin emulsions can be used for the adhesive 105 for coating. Specifically, as the adhesive 105 for splicing that effectively adheres to the surface of the wire material on which the resin of the fiber reinforced plastic wire 2 constituting the fiber reinforced sheet 1 is cured,
(1) Room temperature curable epoxy resin, acrylic resin, styrene resin, vinyl acetate resin, styrene butadiene resin, or
(2) an emulsion of each of the above resins, or
(3) a mixture of two or more of the above resins or resin emulsions,
It is preferable that

Coating splicing adhesive 105 is usually 500~4000g / m ² coating.

  As the binding material 104, a cement-based material that is an inorganic binding material, that is, cement mortar, polymer cement mortar, cement paste, polymer cement paste, or concrete is used.

  In this embodiment, the fiber reinforced sheet 1 having a diameter (d) of the wire 2 of 3 mm at the maximum and a gap (g) of 0.05 mm at the minimum is held on the back surface or the vertical surface of the structure 100 and the wires 2, 2 are used. It is necessary that the binding material 104 oozes out from the gap and the fiber reinforced sheet 1 is consolidated. Accordingly, the bonding thickness 104 of the fiber reinforced sheet 1 and the structure 100 is applied (placed) on the surface of the concrete and the steel plate and is uncured, and is placed on the back surface and the vertical surface of the structure 100 (T ) Is 5 mm or more, dripping and dripping are hardly caused, and the fiber-reinforced sheet 1 having a gap (g) of 0.05 mm for the wire 2, 2 on the coated surface of the binder 104 and a diameter (d) of 3 mm for the wire 2. It is desirable that the bonding material 104 pass between the wires 2 and 2 with a pressure of 1 MPa or less applied and that the sag does not drop.

  In order to give the inorganic bonding material as the bonding material 104 a thickening and thickening effect, and further to add bending toughness, the inorganic bonding material may be made of fiber material such as steel fiber or vinylon fiber. Organic fibers may be mixed.

  Specifically, for example, in the case of a steel fiber, a steel fiber having a diameter of 0.6 to 1.0 mm and a length of 30 to 100 mm is 0.2 to 0.5% (weight) with respect to the inorganic binding material. It is better to add in proportion. In the case of vinylon fibers, it is preferable to add fibers having a diameter of 5 to 20 μm and a length of 4 to 6 mm at a ratio of 0.05 to 2% (weight) with respect to the inorganic binder.

(4th process)
As shown in FIG. 6 (f), a joint adhesive 105 is applied to the fiber reinforced sheet 1 that adheres to the surface of the structure.

The coating adhesive 105 is the same as that described above, and needs to be applied evenly to the surface of the fiber reinforced plastic wire 2 constituting the fiber reinforced sheet 1. Usually, 500 to 4000 g / m ^{2 is} applied to the fiber reinforced sheet 1.

  Moreover, when there is much required reinforcement amount, it is possible to adhere | attach the multiple layers fiber reinforced sheet 1 on the structure surface.

(5th process)
Next, as shown in FIG. 6 (g), the fiber reinforced sheet 1 coated with the jointing adhesive 105 is bonded to the surface of the structure, that is, the cast-in bonding, before the jointing adhesive 105 is cured. Adhere onto the material 104.

(Sixth step)
As shown in FIG. 6 (h), a binder 104 is further provided on the fiber reinforced sheet 1 adhered to the surface 102 of the structure 100, that is, the same binder 104 as that used in the third step, Then, an inorganic binding material is applied at a thickness Ta and finished smooth with a rubber spatula or the like. Thereby, the fiber reinforced sheet 1 is integrated into the structure 100 more firmly.

  The casting thickness (Ta) is appropriately set according to the thickness of the fiber reinforced sheet 1, but is generally about 2 to 10 mm.

  At this time, the fiber reinforced sheet 1 may be pressed by a roller or a rubber spatula so that the air layer at the bonding interface is exhausted from the gap g between the reinforced fiber plastic wires 2 and 2.

(Seventh step)
Furthermore, when a plurality of layers of fiber reinforced sheets 1 are pasted, as in the case described above, the application of the binding material 104 (placement), the pasting of the fiber reinforced sheet 1 and the top coating of the binding material 104 as necessary are repeated. Thus, the multi-layer fiber reinforced sheet 1 can be integrated with the concrete structure 100.

  In the description of the above embodiment, in the fourth step, the adhesive 105 for application is applied to the fiber reinforced sheet 1, and the fiber reinforced sheet 1 is pressed against the surface of the structure to which the binder 104 is applied in the fifth step. In the fourth step, the bonding adhesive 105 is applied to the surface of the structure, and in the fifth step, the fiber reinforced sheet 1 is pressed against the surface of the structure to which the bonding adhesive 105 is applied. It is also possible to bond the fiber reinforced sheet 1 coated with the joint adhesive 105 to the surface of the structure at the same time as applying the joint adhesive 105 to the fiber reinforced sheet 1.

  As understood above, the joint adhesive 105 is applied to the fiber reinforced sheet 1 or the surface of the structure, but in order to enable good application regardless of the gradient of the construction site, Its viscosity is in the range of 100 to 200,000 mPa · sec at 23 ° C., and a thixotropic index (TI value) (ratio of measured values of viscosity at different rotational speeds with a B-type viscometer (viscosity at 2 rpm) ÷ (20 rpm It is preferable that the viscosity in the above range is 1 to 8.

  That is, when the viscosity is smaller than 100 mPa · sec and the TI value is smaller than 1, it is difficult to secure the thickness due to sagging or the like, which is not preferable. Conversely, if the viscosity is larger than 200,000 mPa · sec and the TI value is larger than 8, it is not preferable because workability is deteriorated and filling between the fiber reinforced sheets is poor.

  A modified embodiment of the reinforcing method of the present invention described in the above embodiment will be described with reference to FIG.

(Modified example)
(First step)
As shown in FIGS. 7A and 7B, the weakened portion 101a of the surface to be reinforced (that is, the surface to be bonded) 101 of the concrete structure 100 is ground with a disk sander, sand blast, steel shot blast, water jet or the like. The substrate 50 is removed by means 50, and the surface to be bonded 101 of the structure 100 is treated so as to be a surface 102 having an appropriate roughness.

(Second step)
An epoxy resin primer 103 is applied to the surface 102 subjected to the ground treatment (FIG. 7C). The primer 103 is not limited to an epoxy resin, but is a MMA resin, a vinyl acetate emulsion, an SBR emulsion, an acrylic emulsion, a styrene-acrylic copolymer emulsion, an aqueous resin, or the like. The material is appropriately selected according to the material of the adhesive 105 and the structure to be reinforced 100.

  In addition, the application | coating process of the primer 103 can also be skipped.

(Third step)
As shown in FIG. 7 (d), a joint adhesive 105 is applied to the fiber reinforced sheet 1.

(4th process)
When the primer 103 is applied, after the primer 103 is cured, as shown in FIG. 7E, the fiber reinforced sheet to which the adhesive for adhesive 105 is applied is applied before the adhesive for adhesive 105 is cured. Then, it is pressed against the surface 102 which has been subjected to the ground treatment and adhered to the surface of the structure.

  As the coating adhesive 105, the same adhesive as described in the above embodiment is used.

The coating adhesive 105 needs to be applied evenly on the surface of the fiber reinforced plastic wire 2 constituting the fiber reinforced sheet 1, and usually 500 to 4000 g / m ² applied to the fiber reinforced sheet 1. Is done.

(5th process)
Before the splicing adhesive applied to the fiber reinforced sheet 1 is cured, the binder 104 is placed at a required thickness (T) on the surface of the structure to which the fiber reinforced sheet 1 is bonded (FIG. 7 (f) )). The casting thickness (T) is appropriately set according to the unevenness of the surface of the adherend surface 102 and the thickness of the fiber reinforced sheet 1, but is generally about 2 to 10 mm.

  At this time, the fiber reinforced sheet 1 may be pressed by a roller or a rubber spatula so that the air layer at the bonding interface is exhausted from the gap g between the reinforced fiber plastic wires 2 and 2.

  As the binder 104, cement mortar, polymer cement mortar, cement paste, polymer cement paste, or concrete which is the same inorganic binder as described in the above embodiment is used.

  As described in the above embodiments, the inorganic binder material as the binder 104 has a thickening and thickening effect, and further, the fiber binder is added to the inorganic binder material in order to add bending toughness. For example, it is preferable to add steel fibers or organic fibers such as vinylon fibers.

  In addition, according to the present embodiment, when the fiber reinforced sheet 1 is used, an appropriate space (g) of about 0.05 to 3 mm can be provided between the wires 2, so that air permeability is improved. When the air between the structure 100 to be reinforced and the fiber reinforced sheet 1 is good, or when a plurality of fiber reinforced sheets 1 are laminated as will be described later, the fiber reinforced sheet 1, the interlayer between each other The air is easily discharged, and floating and swelling are less likely to occur.

  Furthermore, since the high-viscosity putty-like bonding material 104 is used, the bonding material 104 can also function as an unevenness correcting material for the concrete surface. Therefore, it is not necessary to apply the adhesive resin after smoothing with the unevenness correction material in advance as in the normal continuous fiber sheet bonding method, and the bonding with the unevenness correction and the fiber reinforced sheet 1 is performed once. It is extremely efficient because it can be performed simultaneously by application.

  Similar to the conventional continuous fiber sheet bonding method, since a wide sheet-like reinforcing material of about 100 to 1000 mm, that is, the fiber reinforced sheet 1 is used, it is easy to cover and cover the entire reinforcing surface of the reinforcing structure 100. . In addition, the bonding area can be increased compared to the conventional method of bonding a FRP plate having a narrow width of about 50 mm, the peeling of the bonding surface hardly occurs, and a high reinforcing effect can be obtained.

(Sixth step)
Furthermore, when a plurality of layers of fiber reinforced sheet 1 are attached, a plurality of layers of fibers can be obtained by repeating the application of the fiber reinforced sheet 1 and the application (placement) of the binding material 104 as necessary. The reinforcing sheet 1 can be integrated with the concrete structure 100.

  In the description of the above embodiment, in the third step, the jointing adhesive 105 is applied to the fiber reinforced sheet 1, and the fiber reinforced sheet 1 is pressed against the surface of the structure to which the binder 104 is applied in the fourth step. In the third step, the bonding adhesive 105 is applied to the surface of the structure, and in the fourth step, the fiber reinforced sheet 1 is pressed against the surface of the structure to which the bonding adhesive 105 is applied. It is also possible to bond the fiber reinforced sheet 1 coated with the joint adhesive 105 to the surface of the structure at the same time as applying the joint adhesive 105 to the fiber reinforced sheet 1.

  As described above, according to the method for reinforcing a structure of the present invention, there is no need for on-site impregnation of resin into the fiber bundle constituting the fiber reinforced sheet, there is no fear of impregnation, and work efficiency is high. In addition to the advantages of using a fiber reinforced sheet, when using an inorganic binder that is a cement-based material as the binder, the bond with the binder can be bonded extremely firmly, and the fiber reinforced sheet Can be prevented from peeling off from the cement material before reaching the breaking strength.

Next, the following experiment was conducted in order to demonstrate the operational effect of the structure reinforcing method according to the present invention.
Test Method The experiment was performed in accordance with JIS A 1106 (concrete bending strength test method). The test temperature was 23 ° C. The test was conducted by the concrete bending test method by the center point loading method.
-Test piece The test piece was made into four types of type AD shown to Fig.8 (a), (b), (c), (d). Type D shown in FIG. 8 (d) is a blank specimen for comparison, length (Lo) 160 mm × thickness (To) 40 mm × width (length perpendicular to the paper surface of FIG. 8) 40 mm JIS standard. Mortar (non-muscle), that is, a reference mortar based on JIS R5201.

Type A shown in FIG. 8 (a) is a test body having a configuration reinforced in accordance with the present invention described in Example 1, and the thickness T _F of the reinforcing layer configured in accordance with the present invention is 10 mm. The total thickness (T _TOTAL ) of the test piece including the test specimen was set to 40 mm, which was the same as the thickness To of the type D blank test specimen. The length and width were the same as the blank specimen.

Type B shown in FIG. 8 (b) is a test body having a structure reinforced in accordance with the present invention described in the modified example. The thickness T _F of the reinforcing layer configured in accordance with the present invention is 10 mm, and the mortar The total thickness (T _TOTAL ) of the test piece including the test specimen was 40 mm. The length and width were the same as the blank specimen.

The type C shown in FIG. 8C is a structure in which the carbon fiber reinforced sheet 1 used in Example 1 is bonded to a type D mortar specimen (FIG. 8D) with an epoxy resin, that is, according to a conventional method. The test piece was reinforced, and the total thickness (T _TOTAL ) of the test piece including the mortar test piece was 40 mm. The length and width were the same as the blank specimen.

  The materials used in types A and B according to this example were as follows.

  The fiber reinforced sheet 1 used in this test was the fiber reinforced sheet 1 having the configuration described with reference to FIG.

  The fiber reinforced plastic wire 2 in the fiber reinforced sheet 1 uses PAN-based carbon fiber strands having an average diameter of 7 μm and a convergent number of 12,000 as the reinforcing fibers f, impregnated with a room temperature curable epoxy resin as the matrix resin R, and cured. Produced. The resin impregnation amount was 50% by weight, and the cured fiber reinforced plastic wire 2 had a circular cross section with a diameter (d) of 1.1 mm.

  The fiber reinforced plastic wire 2 obtained in this way was aligned in one direction and arranged in a slender shape, and then the polyester fiber was held as a weft 3 in a sheet form by plain weaving. The interval (P) between the wefts 3 was 50 mm. Further, the gap (g) between the wires 2 and 2 was 0.1 to 0.3 mm.

A polymer cement mortar (“Attack SD” (trade name) manufactured by Nippon Steel Composite Co., Ltd.) is used as the binder 104, and a room temperature curable epoxy resin (manufactured by Nippon Steel Composite Co., Ltd.) is used as the adhesive 105. use the "FJ-C primer" (trade name)), it was applied at 3.0kg / m ^2.

  The results of the concrete bending test are shown in Table 1.

  As can be seen in Table 1, compared to the unreinforced mortar (type D) bending strength of 9.96N, the type C by reinforcement according to the conventional construction method showed a bending strength of 1.57 times.

  On the other hand, types A and B according to the present invention showed 1.7 times and 1.75 times bending strength, respectively, as compared with unreinforced mortar (type D).

  In addition, as for the amount of displacement at the breaking point, in the non-reinforced mortar (type D), the crushed specimen was broken with a small amount of displacement of 0.25 mm. It was confirmed that it could hold up.

  Furthermore, it was confirmed that the test pieces of type A and B according to the present invention did not cause peeling between the sheet / polymer cement mortar and the base, and were effective as adhesiveness.

  Thus, it became clear that the reinforcing method of a structure according to the present invention can effectively reinforce a reinforced concrete beam.

  In the first embodiment and the modified embodiment, the reinforcement of the concrete structure 100 has been described. However, the reinforcing method using the fiber reinforced sheet 1 of the present invention is a steel structure, a wooden structure, and a plastic structure. Can be similarly applied to the reinforcement of these combined structures, and the same effects can be achieved.

DESCRIPTION OF SYMBOLS 1 Fiber reinforced sheet 2 Fiber reinforced plastic wire material 3 Wire material fixing material (weft, mesh support sheet, flexible belt material)
10 Unidirectional carbon fiber sheet (continuous fiber sheet)
DESCRIPTION OF SYMBOLS 100 Structure 103 Primer 104 Binder 105 Adhesive for coating

Claims (14)

A fiber reinforced sheet in which reinforcing fibers are impregnated with matrix resin and hardened continuous fiber reinforced plastic wires are aligned in a longitudinal direction and the wires are fixed to each other with a wire fixing material. In a method for reinforcing a structure that is bonded and integrated with a binder,
(A) a step of grounding the surface of the structure;
(B) An inorganic bond in which a joint adhesive is applied to the surface of the surface-treated structure and then cement mortar, polymer cement mortar, cement paste, polymer cement paste, or concrete is used as a binder. The process of placing the material,
(C) The structure is obtained by pressing the fiber-reinforced sheet coated with a joint adhesive on the inorganic binding material placed in the step (b) before the joint adhesive is cured. Adhering to the surface of objects,
(D) A step of placing an inorganic binding material as cement mortar, polymer cement mortar, cement paste, polymer cement paste, or concrete as a binder on the surface of the structure to which the fiber reinforced sheet is bonded. ,
A method for reinforcing a structure, comprising: A fiber reinforced sheet in which reinforcing fibers are impregnated with matrix resin and hardened continuous fiber reinforced plastic wires are aligned in a longitudinal direction and the wires are fixed to each other with a wire fixing material. In a method for reinforcing a structure that is bonded and integrated with a binder,
(A) a step of grounding the surface of the structure;
(B) An inorganic bond in which a joint adhesive is applied to the surface of the surface-treated structure and then cement mortar, polymer cement mortar, cement paste, polymer cement paste, or concrete is used as a binder. The process of placing the material,
(C) A step of applying an adhesive for coating on the inorganic binding material placed in the step (b),
(D) a step of pressing the fiber reinforced sheet and adhering it to the surface of the structure before the coating adhesive applied in the step (c) is cured;
(E) placing a cement mortar, a polymer cement mortar, a cement paste, a polymer cement paste, or an inorganic binder as concrete on the surface of the structure to which the fiber reinforced sheet is bonded ,
A method for reinforcing a structure, comprising: A fiber reinforced sheet in which reinforcing fibers are impregnated with matrix resin and hardened continuous fiber reinforced plastic wires are aligned in a longitudinal direction and the wires are fixed to each other with a wire fixing material. In a method for reinforcing a structure that is bonded and integrated with a binder,
(A) a step of grounding the surface of the structure;
(B) a step of pressing the fiber-reinforced sheet coated with a joint adhesive on the surface of the structure subjected to the base treatment and bonding the fiber reinforced sheet to the surface of the structure before the joint adhesive is cured;
(C) Placing an inorganic binding material to be cement mortar, polymer cement mortar, cement paste, polymer cement paste, or concrete as a binder on the surface of the structure to which the fiber reinforced sheet is bonded. ,
A method for reinforcing a structure, comprising: A fiber reinforced sheet in which reinforcing fibers are impregnated with matrix resin and hardened continuous fiber reinforced plastic wires are aligned in a longitudinal direction and the wires are fixed to each other with a wire fixing material. In a method for reinforcing a structure that is bonded and integrated with a binder,
(A) a step of grounding the surface of the structure;
(B) applying a coating adhesive to the surface of the structure subjected to the ground treatment;
(C) before the adhesive for coating applied in the step (b) is cured, the step of pressing the fiber reinforced sheet to adhere to the surface of the structure;
(D) A step of placing an inorganic binding material as cement mortar, polymer cement mortar, cement paste, polymer cement paste, or concrete as a binder on the surface of the structure to which the fiber reinforced sheet is bonded. ,
A method for reinforcing a structure, comprising:   5. The method according to claim 1, wherein a primer is applied to the surface of the structure subjected to the ground treatment in the step (a), and the step (b) is performed after the primer is cured. A method for reinforcing a structure according to claim 1.   The fiber reinforced sheet is laminated and adhered to the surface of the structure in a plurality of layers, and is integrated with the structure. The structure according to any one of claims 1 to 5, Reinforcement method.   Reinforcing fibers of the fiber reinforced plastic wire are carbon fiber, glass fiber, basalt fiber; metal fiber such as boron fiber, titanium fiber, steel fiber; aramid, PBO (polyparaphenylene benzbisoxazole), polyamide, polyarylate, polyester The method for reinforcing a structure according to any one of claims 1 to 6, wherein the organic fiber is used alone or in a hybrid mixed with a plurality of types.   The matrix resin of the fiber reinforced plastic wire is a thermosetting resin such as a room temperature curing type or thermosetting type epoxy resin, vinyl ester resin, MMA resin, acrylic resin, unsaturated polyester resin, or phenol resin, or nylon. The method for reinforcing a structure according to any one of claims 1 to 7, which is a thermoplastic resin such as vinylon. The splicing adhesive is
(1) Room temperature curable epoxy resin, acrylic resin, styrene resin, vinyl acetate resin, styrene butadiene resin, or
(2) an emulsion of each of the above resins, or
(3) a mixture of two or more of the above resins or resin emulsions,
The method for reinforcing a structure according to any one of claims 1 to 8, wherein:   10. The adhesive according to claim 9, wherein the adhesive has a viscosity in a range of 100 to 200,000 mPa · sec at 23 ° C. and a thixotropic index in a range of 1 to 8. 10. Method of reinforcing the structure.   The reinforcing method for a structure according to any one of claims 1 to 10, wherein the inorganic binding material is mixed with a fiber material.   The fiber-reinforced plastic wire has a circular cross-sectional shape having a diameter of 0.5 to 3 mm, or a rectangular cross-sectional shape having a width of 1 to 10 mm and a thickness of 0.1 to 2 mm. The method for reinforcing a structure according to any one of claims 1 to 11.   The method for reinforcing a structure according to any one of claims 1 to 12, wherein the fiber reinforced plastic wires are separated from each other by 0.05 to 3.0 mm.   The method for reinforcing a structure according to any one of claims 1 to 13, wherein the fiber reinforced sheet has a width of 100 mm to 10 m.

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