JP2020056168A - Reinforcing method for reinforced concrete structure - Google Patents

Abstract

To provide a reinforcing method of a concrete structure capable of preventing damage of concrete due to rust of reinforcing bars in a reinforced concrete structure by suppressing corrosion of the reinforcing bars and improving adhesion performance of a fiber sheet to the surface of the reinforced concrete structure.SOLUTION: A reinforcing method of a reinforced concrete structure 100 for bonding and integrating a fiber sheet 1 containing reinforcing fibers, includes the steps of (a) coating the surface of the reinforced concrete structure with a silane impregnating material 102, (b) forming a primer layer 104 by applying a primer 103 containing a silane coupling agent to the surface of a reinforced concrete structure coated with a silane-based impregnation material 102, and (c) bonding the fiber sheet 1 to the surface of the reinforced concrete structure having the primer layer 104 formed thereon with an adhesive 105.SELECTED DRAWING: Figure 1

Description

  The present invention uses a sheet-like or plate-like reinforcing fiber-containing material containing reinforcing fibers (hereinafter referred to as a “fiber sheet”) to form beams, girder members, walls, columns, floor slabs, and the like. The present invention relates to a method for reinforcing a reinforced concrete structure such as a slab member for repairing and reinforcing (hereinafter, simply referred to as "reinforcement") a reinforced concrete structure which is a building or civil engineering structure.

  In recent years, as a method of reinforcing an existing or newly installed reinforced concrete structure, a carbon fiber sheet bonding or winding a continuous reinforcing fiber sheet such as a carbon fiber sheet or an aramid fiber sheet as a fiber sheet on the surface of the reinforced concrete structure. There is a continuous fiber sheet bonding method such as a construction method or an aramid fiber sheet bonding method, or a method of bonding and curing a fiber sheet obtained by impregnating a continuous fiber bundle with an uncured matrix resin.

  Further, in order to omit the in-situ resin impregnation, an FRP plate bonding reinforcement method of bonding a factory-produced FRP plate having a thickness of 1 to 5 mm and a width of about 5 to 10 cm to a concrete surface using a resin adhesive has been developed.

  The reinforced concrete structure that has been subjected to such a continuous fiber reinforcement method can reduce the bending and shear stress of the reinforced concrete structure by bonding the fiber sheet integrally with the reinforced concrete structure, and can adhere to the entire surface of the reinforced concrete structure. In this case, it is possible to prevent incoming salt and the like from entering the reinforced concrete structure.

  However, in a reinforced concrete structure that already contains an internal salt, the internal salt does not change even when the continuous fiber reinforcement method is used. In addition, for the reinforcement of concrete structures, it is common to use an economical design method, and fiber sheets are not bonded to the entire surface of the reinforced concrete structure. Some parts of the concrete are exposed. Therefore, it is assumed that water, oxygen, and the like infiltrate into the concrete from this portion, and damage to the concrete representing explosion due to rust of the reinforcing bar occurs.

  Therefore, conventionally, in order to suppress corrosion of reinforcing bars in a reinforced concrete structure, an aqueous composition containing a silane monomer (hereinafter, referred to as a “silane-based impregnating material”) as disclosed in Patent Document 1 is used for a reinforced concrete structure. Application to the surface has been performed. More specifically, for example, a silane-based impregnating material such as an alkylalkoxysilane contains only a silane monomer as a reaction composition, does not contain a polysiloxane (silane polymer) or other polymer composition, and is deep into the concrete. It has the property of penetrating. The penetration range is generally 10 mm to 15 mm from the surface of the concrete structure. The silane-based impregnated material that has deeply penetrated remains in the concrete for a long period of time, including around the reinforcing bar, and continues to be dehydrated from the area including the reinforcing bar placement position due to the catalytic effect of water, which is a typical reaction of silane monomers. It has the feature that water does not exist around the reinforcing bar. Further, the silane-based impregnated material remaining inside the concrete structure is polymerized to become a silane polymer, which has a water absorption preventing function, and has a performance of preventing water from entering the inside of the concrete.

Japanese Patent No. 4778189

  As described above, the silane-based impregnated material is excellent in the rust prevention effect on the reinforcing steel in the reinforced concrete structure. On the other hand, according to the results of the research experiments of the present inventors, a continuous fiber sheet was bonded with a resin adhesive to a reinforced concrete structure coated with a silane-based impregnating material having a function of inhibiting corrosion of reinforcing steel for rust prevention. The following problems were found when the continuous fiber adhesion reinforcement method of reinforcing by using the method was adopted. That is, the silane-based impregnating material applied to the reinforced concrete structure is polymerized to form a silane polymer, and the water is discharged with the formation. Due to this moisture, when the fiber sheet is bonded to the concrete structure with the adhesive, the adhesive is repelled, and there is a problem that good adhesion cannot be obtained. The problem is that after applying the silane-based impregnating material, provide a sufficient curing period to remove the generated moisture and completely dry the applied surface, and then attach the fiber sheet to the concrete structure with an adhesive. Can solve the problem, but the operation time is prolonged, and there is a problem in the work efficiency.

  The present inventors, in order to solve the above problems, as a result of conducting many research experiments, in the pre-process of bonding the fiber sheet with an adhesive, first apply a silane-based impregnating material to the surface of the reinforced concrete structure, Thereafter, by applying a primer containing a silane coupling agent to the surface of the structure to which the silane-based impregnating material has been applied, the reinforcing steel rust-preventing effect of the silane-based impregnating material is achieved, and It has been found that the problem of the discharged water can be solved to improve the bonding performance of the fiber sheet to the concrete structure surface. The present invention has been made based on such novel findings of the present inventors.

  That is, an object of the present invention is to provide a reinforced concrete structure capable of suppressing corrosion of a reinforcing bar in a reinforced concrete structure, avoiding damage to the concrete due to rust of the reinforcing bar, and improving the bonding performance of a fiber sheet to the surface of the reinforced concrete structure. It is to provide a method of reinforcing a structure.

The above object is achieved by a method for reinforcing a reinforced concrete structure according to the present invention. In summary, the present invention relates to a method for reinforcing a reinforced concrete structure in which a fiber sheet containing reinforcing fibers is bonded and integrated,
(A) applying a silane-based impregnating material to the surface of the reinforced concrete structure;
(B) applying a primer containing a silane coupling agent to the surface of the reinforced concrete structure to which the silane-based impregnating material has been applied, to form a primer layer;
(C) adhering the fiber sheet to the surface of the reinforced concrete structure on which the primer layer is formed, with an adhesive;
A method for reinforcing a reinforced concrete structure characterized by having:

  According to an embodiment of the present invention, the content of the silane coupling agent in the primer is 0.1 to 5.0% by weight.

  According to another embodiment of the present invention, the primer further comprises 0.1 to 10% by weight of a powdery filler.

According to another embodiment of the present invention, the silane coupling agent has a main component represented by the following general formula (I):
Y-Si- (OX) ₃ (I)
here,
Y is an organic functional group capable of reacting and bonding with an organic material,
OX is an inorganic functional group that reacts with the inorganic material,
It is an organosilicon compound. Here, the organic functional group is an amino group, a mercapto group, a vinyl group, or an epoxy group,
The inorganic functional group can be an alkoxy group.

  According to another embodiment of the present invention, the silane coupling agent is 3-glycidoxypropyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane. Silane, 3-glycidoxypropylmethyldiethoxysilane, or 3-glycidoxypropyltriethoxysilane.

According to another embodiment of the present invention, the silane-based impregnating material has the general formula (II) as component A:
R-SiR ¹ _x (O) _y R ² _z (II)
[Where,
R represents a linear or branched alkyl group having 3 to 20 carbon atoms,
R ¹ represents a linear or branched alkyl group having 1 to 4 carbon atoms,
R ² represents a linear or branched alkoxy group having 1 to 4 carbon atoms or a hydroxy group, wherein the groups R ² may be the same or different Often,
x is 0, 1 or 2;
y is 0.0 to 1.5,
z is 0, 1, 2 or 3 and (x + 2y + z) = 3], and at least one organosilane or organosiloxane or a mixture thereof, and as component D, HO—CH ₂ —CH ₂ — Containing N (CH ₃ ) ₂ or HO—CH ₂ —CH ₂ —N (C ₂ H ₅ ) ₂ or a mixture thereof, and wherein component A and component D are 1: 1 to 26.2: 1 It is contained in a molar ratio.

According to another embodiment of the present invention, the silane-impregnated material, as component _{A, n-C 3 H 7} Si (OCH 3) 3, n-C 3 H 7 Si (OC 2 H 5) 3, i _{-C 3 H 7 Si (OCH 3} ) 3, i-C 3 H 7 Si (OC 2 H 5) 3, n-C 4 H 9 Si (OCH 3) 3, n-C 4 H 9 Si (OC 2 _{H 5) 3, i-C} 4 H 9 Si (OCH 3) 3, i-C 4 H 9 Si (OC 2 H 5) 3, n-C 5 H 11 Si (OCH 3) 3, n-C 5 H ₁₁ Si (OC ₂ H ₅ ) ₃ , i-C ₅ H ₁₁ Si (OCH ₃ ) ₃ , i-C ₅ H ₁₁ Si (OC ₂ H ₅ ) ₃ , n-C ₆ H ₁₃ Si (OCH ₃ ) _{3, n-C 6 H 13} Si (OC 2 H 5) 3, i-C 6 H 13 Si (OCH 3) 3, i _{C 6 H 13 Si (OC 2} H 5) 3, n-C 8 H 17 Si (OCH 3) 3, n-C 8 H 17 Si (OC 2 H 5) 3, i-C 8 H 17 Si (OCH _{3) 3, i-C 8} H 17 Si (OC 2 H 5) 3, n-C 10 H 21 Si (OCH 3) 3, n-C 10 H 21 Si (OC 2 H 5) 3, i-C _{10 H 21 Si (OCH 3)} 3, i-C 10 H 21 Si (OC 2 H 5) 3, n-C 16 H 33 Si (OCH 3) 3, n-C 16 H 33 Si (OC 2 H 5 ) ₃ , i-C ₁₆ H ₃₃ Si (OCH ₃ ) ₃ , i-C ₁₆ H ₃₃ Si (OC ₂ H ₅ ) ₃ or a partial condensate comprising at least one of the above-mentioned alkylalkoxysilanes or the above-mentioned alkylalkoxysilane A mixture consisting of Or a mixture of an alkylalkoxysilane and a partial condensate.

  According to another embodiment of the present invention, the silane-based impregnating material contains dinonylnaphthalenesulfonic acid or an alkaline earth metal salt thereof or a mixture thereof as Component C.

  According to another embodiment of the present invention, the silane-based impregnating material contains Component C in an amount of 0 to 50% by mass relative to Component A. Preferably, the silane-based impregnating material contains component C in an amount of 0.01 to 10% by mass relative to component A. More preferably, the silane-based impregnating material contains component C in an amount of 0.5 to 5% by mass relative to component A.

  According to another embodiment of the present invention, the silane-based impregnant contains as additional components diisotridecyl adipate, mineral oil, benzene hydrocarbons, alcohols, rheology aids, thickeners or mixtures thereof. .

  According to another embodiment of the present invention, the adhesive used in the step (b) is a cold-setting epoxy resin, an epoxy acrylate resin, an acrylic resin, an MMA resin, a vinyl ester resin, an unsaturated polyester resin, or It is a photocurable resin.

According to another embodiment of the present invention, the adhesive used in the step (b) is a cold-setting epoxy resin, and the epoxy resin adhesive is provided as a two-component type of a main agent and a curing agent,
(I) Main agent: An epoxy resin is used as a main component, and a silane coupling agent or the like is used as an adhesion enhancer if necessary.
(Ii) Curing agent: An amine is contained as a main component, and an amine equivalent ratio of each of an epoxy resin as a main component and a curing agent is 1: 1.
The composition.

  According to another embodiment of the present invention, the fiber sheet is a fiber sheet in which continuous reinforcing fibers aligned in one direction are fixed to each other with a wire fixing material. According to another embodiment, the fiber sheet is a fiber sheet in which continuous reinforcing fibers are impregnated with a resin and the resin is cured.

  According to another embodiment of the present invention, the fibrous sheet comprises a plurality of continuous fiber-reinforced plastic wires that are impregnated with a matrix resin in a reinforcing fiber and are hardened and continuous in a longitudinal direction, and the wires are mutually wire-shaped. It is a fiber sheet fixed with a fixing material. According to another embodiment, the fiber sheet is a fiber sheet in which a resin is impregnated between the fiber reinforced plastic wires and the resin is cured.

  ADVANTAGE OF THE INVENTION According to this invention, corrosion of the reinforcement in a reinforced concrete structure can be suppressed, the damage of the concrete resulting from the rust of a reinforcement can be avoided, and the adhesive performance of the fiber sheet to the reinforced concrete structure surface can be improved.

BRIEF DESCRIPTION OF THE DRAWINGS It is sectional drawing of the concrete structure reinforced by the reinforcement method of the reinforced concrete structure of this invention. It is a figure showing an example of a fiber sheet which can be used for a method of reinforcing a reinforced concrete structure of the present invention. It is a figure showing other examples of a fiber sheet which can be used for a method of reinforcing a reinforced concrete structure of the present invention. It is a perspective view showing other examples of a fiber sheet which can be used for a method of reinforcing a reinforced concrete structure of the present invention. FIGS. 5A and 5B are cross-sectional views of a fiber reinforced plastic wire constituting a fiber sheet that can be used in the method of reinforcing a reinforced concrete structure according to the present invention. FIGS. 6A and 6B are perspective views showing another embodiment of a fiber sheet that can be used in the method of reinforcing a reinforced concrete structure according to the present invention. FIGS. 7A to 7E are process diagrams illustrating an embodiment of a method for reinforcing a reinforced concrete structure according to the present invention. It is a figure explaining the mechanism of the rust prevention effect of the reinforcing steel in the reinforced concrete structure of the silane impregnation material used in the present invention. FIGS. 9A to 9C are views for explaining the configuration of a shear adhesion test for demonstrating the method for reinforcing a concrete structure according to the present invention, and FIG. 9A is a front sectional view. 9B and 9C are side sectional views. FIGS. 10 (1) to 10 (6) are photographs showing the state of peeling failure of a specimen showing the results of a shear adhesion test for verifying the method of reinforcing a concrete structure according to the present invention. FIGS. 11A and 11B are diagrams illustrating a Kenken-type adhesion test for demonstrating the method of reinforcing a concrete structure according to the present invention, and FIG. 11A is a perspective view of an adhesion test device. FIG. 11B is a schematic cross-sectional view of a reinforced test specimen and a steel attachment.

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

Example 1
Referring to FIG. 1, the characteristic structure of the method for reinforcing a reinforced concrete structure according to the present invention will be described. According to the present invention, a reinforced concrete structure 100 is provided on a surface 101 of a structure impregnated with a silane-based impregnating material 102. Then, the primer 103 is applied to form a primer layer 104, and the fiber sheet 1 containing the reinforcing fibers f is further adhered thereon with a resin adhesive 105 to be integrated.

Furthermore, the method for reinforcing a reinforced concrete structure according to the present invention relates to a method for reinforcing a reinforced concrete structure in which a fiber sheet 1 containing reinforcing fibers f is bonded and integrated.
(A) applying a silane-based impregnating material 102 to a surface 101 of a reinforced concrete structure 100;
(B) a step of applying a primer 103 containing a silane coupling agent to the surface 101 of the reinforced concrete structure 100 to which the silane-based impregnating material 102 has been applied to form a primer layer 104;
(C) a step of bonding the fiber sheet 1 to the surface 101 of the reinforced concrete structure 100 on which the primer layer 104 is formed, with an adhesive 105;
have.

  Before describing in more detail one embodiment of the method for reinforcing a reinforced concrete structure according to the present invention, first, a fiber sheet 1 used in the present invention will be described.

(Fiber sheet)
In the present invention, various forms of the fiber sheet 1 can be used. Examples of the fiber sheet 1 will be specifically described as specific examples 1 to 3, but the form of the fiber sheet 1 used in the present invention is not limited to those shown in these specific examples.

Example 1
FIG. 2 shows one embodiment of the fiber sheet 1 that can be used in the present invention. The fiber sheet 1 is a resin-impregnated fiber sheet 1 </ b> A which is formed in a sheet shape by aligning continuous reinforcing fibers f in one direction.

That is, the fiber sheet 1 </ b> A can be configured such that a reinforcing fiber sheet made of continuous reinforcing fibers f aligned in one direction is held by a wire fixing material 3 such as a mesh-like support sheet. For example, when carbon fibers are used as the reinforcing fibers f, for example, a plurality of resin-impregnated single fiber bundles in which 6000 to 24000 single fibers (carbon fiber monofilaments) having an average diameter of 7 μm are converged in parallel in one direction Used to align with. The fiber basis weight of the carbon fiber sheet 1A is usually 30 to 1000 g / m ² .

  The surface of the warp yarns 4 and the weft yarns 5 constituting the mesh-like support sheet as the wire fixing material 3 is impregnated in advance with a low melting point type thermoplastic resin, and the mesh-like support sheet 3 is arranged in a sheet-like carbon. The fibers are laminated on one side or both sides and heated and pressurized, and the portions of the warp yarns 4 and the weft yarns 5 of the mesh-like support sheet 3 are welded to the carbon fiber sheet.

  In addition to the biaxial configuration, the mesh-shaped support sheet 3 is formed by orienting glass fibers in three axes, or by using only the weft yarns 5 that are orthogonal to glass fibers arranged in one direction. It is also possible to arrange the so-called uniaxially oriented carbon fiber and adhere it to the carbon fibers aligned in the sheet shape.

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

Example 2
Further, as shown in FIG. 3, the fiber sheet 1 is obtained by impregnating a resin Re into a reinforcing fiber sheet 1 in which a plurality of continuous reinforcing fibers f are aligned in one direction, for example, a fiber sheet 1A as shown in FIG. Alternatively, a fiber sheet (a so-called FRP plate) 1B obtained by curing the resin may be used. Needless to say, the fiber sheet 1B may be an FRP plate having a thickness of about 0.5 to 10 mm composed of a single layer or a plurality of layers in which fibers are arranged in one direction or a plurality of directions.

  In the fiber sheets 1A and 1B described in the specific examples 1 and 2, the reinforcing fibers f are not limited to carbon fibers, but are glass fibers, basalt fibers; metal fibers such as boron fibers, titanium fibers, and steel fibers. And organic fibers such as aramid, PBO (polyparaphenylene benzobisoxazole), polyamide, polyarylate, polyester, and high-strength polyester; can be used alone or in a hybrid form by mixing plural kinds thereof. .

  Further, as the resin Re in the case of the fiber sheet 1B in the specific example 2, a thermosetting resin or a thermoplastic resin can be used, and as the thermosetting resin, a room temperature curing type or a thermosetting type epoxy resin is used. , A vinyl ester resin, an MMA resin, an acrylic resin, an unsaturated polyester resin, or a phenol resin are preferably used. As the thermoplastic resin, an epoxy resin, nylon, vinylon, or the like is preferably used. Further, the fiber volume content (Vf) is set to 40 to 75%, preferably 50 to 70%.

Example 3
4 and FIG.
1538113720838_0
As shown in FIG. 5, as the fiber sheet 1, a plurality of continuous fine fiber reinforced plastic wires 2 having a small diameter impregnated and cured with a matrix resin Rf are arranged in a longitudinally slender shape, and the respective wires 2 are connected to each other. The fiber sheet 1C fixed by the fixing material 3 can also be used.

  The fiber-reinforced plastic wire 2 has a substantially circular cross-sectional shape (FIG. 5A) having a diameter (d) of 0.5 to 3 mm, or a width (w) of 1 to 10 mm and a thickness (t) of 0. It can be a substantially rectangular cross-sectional shape (FIG. 5B) of .1 to 2 mm. Of course, other various cross-sectional shapes can be used as needed.

  As described above, in the fibrous sheet 1C that is drawn and aligned in one direction, the wires 2 are closely spaced from each other by a gap (g) = 0.05 to 3.0 mm, and the wires 2 are fixed by the wire fixing material 3. Fixed. Further, the length (L) and width (W) of the fiber sheet 1C thus formed are appropriately determined according to the size and shape of the structure to be reinforced. , The total width (W) is 100 to 1000 mm. In addition, a strip (L) having a length (L) of about 1 to 5 m, or a strip having a length of 100 m or more can be manufactured.

  It is also possible to manufacture the fiber sheet 1C with the length (L) of about 1 to 5 m and the width W longer than that of about 1 to 10 m.

  Also in the case of the fiber sheet 1C, 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 benzobisoxazole) , Polyamide, polyarylate, polyester, and high-strength polyester; can be used alone or in combination of two or more. The matrix resin Rf 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 thermosetting type epoxy resin, A vinyl ester resin, an MMA resin, an acrylic resin, an unsaturated polyester resin, a phenol resin, or the like is preferably used. As the thermoplastic resin, an epoxy resin, nylon, vinylon, or the like is preferably used. Further, the fiber volume content (Vf) is set to 40 to 75%, preferably 50 to 70%.

  As a method for fixing each wire 2 with the wire fixing material 3, as shown in FIG. 4, for example, a weft yarn is used as the wire fixing material 3, and a plurality of wires arranged in a one-sided slender shape are used. A method of driving and knitting a wire having a sheet form composed of two, that is, a continuous wire sheet at a predetermined interval (P) perpendicular to the wire can be adopted. 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 sheet 1.

  At this time, the weft yarn 3 is, for example, a yarn in which a plurality of glass fibers or organic fibers having a diameter of 2 to 50 μm are bundled. Nylon, vinylon, polyester and the like are preferably used as the organic fibers.

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

  That is, the above specific example in which a plurality of wire rods 2 arranged in a sheet form in a sheet form, that is, one side or both sides of the wire rod sheet are made of, for example, glass fiber or organic fiber having a diameter of 2 to 50 μm. The structure supported by the mesh-shaped support sheet 3 having the same structure as that described in 1 can also be adopted.

  Further, as another method of fixing each wire 2 in a sloping shape, as shown in FIG. 6B, as the wire fixing material 3, for example, a flexible band 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 of the fiber reinforced plastic wires 2 arranged in a sheet form in the form of a sheet. Paste and fix.

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

  Furthermore, the flexible band member 3 can also be achieved by heat-sealing a thermoplastic resin such as nylon or EVA resin in a band shape on one side or both sides in a direction perpendicular to the longitudinal direction of the wire 2. Is done.

(Reinforcement method)
Next, an embodiment of a method for reinforcing a reinforced concrete structure according to the present invention will be described in more detail with reference to FIG. According to the present invention, the reinforced concrete structure is reinforced using the fiber sheet 1 manufactured as described above.

  In other words, according to the method for reinforcing a concrete structure of the present invention, for example, the continuous fiber-reinforced plastic wire 2 having a small diameter impregnated with the matrix resin R and cured as described in the specific example 3 is used as the fiber sheet 1. It is possible to use a fiber sheet 1C in which a plurality of fibers are aligned in the longitudinal direction in a sloping manner, and each wire 2 is fixed to each other by a wire fixing material 3. The fiber sheet 1C is bonded to the surface 101 of the concrete structure 100 on which the silane-based impregnating material 102 has been applied and impregnated with an adhesive 105 via a primer layer 104 formed by applying a primer 103. At this time, for example, when the fiber sheet 1A described in the specific example 1 is used, the resin (matrix resin) impregnation of the fiber sheet 1A with the adhesive is performed simultaneously with the bonding of the fiber sheet 1A to the concrete structure. Can also be done.

  When the concrete structure 100 is reinforced, the orientation direction of the reinforcing fibers is substantially matched to the main stress direction of the tensile stress or the compressive stress generated by the bending moment for a member (structure) mainly receiving the bending moment and the axial force. By bonding, the fiber sheet 1 effectively bears stress, and it is possible to efficiently improve the load carrying capacity of the structure.

  When a bending moment acts in two orthogonal directions, two or more layers of the fiber sheet 1 are orthogonally bonded so that the orientation direction of the reinforcing fibers f of the fiber sheet 1 substantially matches the main stress generated by the bending moment. By doing so, the load carrying capacity can be efficiently improved.

  With reference to FIGS. 7A to 7E, a method of reinforcing a concrete structure in the present embodiment will be described in more detail.

(First step)
A ground treatment is performed on the surface to be reinforced of the reinforced concrete structure 100, that is, the surface 101 to be bonded of the fiber sheet 1 (FIG. 7A). In the base treatment, the grinding means 50 such as a disc sander, sand blast, steel shot blast, wire brush, water jet, etc. is used to remove latencies, oils, dirt, etc. in the case of a newly installed reinforced concrete structure. In the case of the reinforced concrete structure described above, the coating film, oil and grease, dirt, etc. are removed, and if there is a defective portion, a floating portion, or an excessive crack, repair is performed in advance.

(2nd process)
The silane-based impregnating material 102 is sprayed on the surface 101 to be reinforced which has been subjected to the base treatment in this manner by using an appropriate application means such as a spatula, a trowel, or a roller, and is applied by brush application, roller application, knife application, or the like. (FIG. 7 (b)).

  Here, the mechanism of the rust-preventing action of the reinforcing bar in the reinforced concrete structure 100 of the silane-based impregnating material 102 in the present invention will be briefly described with reference to FIG.

  As can be understood with reference to FIG. 8, the silane-based impregnating material 102 is a low-molecular composition containing a silane monomer, for example, an alkylalkoxysilane, and penetrates deep into the concrete. When the molecular weight of the silane monomer is, for example, 178.3, the permeation range is 11.4 mm at a concrete blending W / C of 40% in the concrete structure 100 and 13.7 mm at a W / C of 50%. , W / C = 60% and 14.5 mm.

  The silane monomer is converted into an alkylsilane triol (trivalent silanol) by a reaction (hydrolysis) with water in the concrete, and the silanol is polycondensed and polymerized by a siloxane bond (Si-O), thereby obtaining water repellency and electric repellency. A polysiloxane (silicone) having an insulating property is formed. This silicone reacts with hydroxyl groups (-OH) in concrete or on the surface of a reinforcing bar to form a protective layer of the reinforcing bar that replaces the passive film of the reinforcing bar. That is, the protective layer thus formed is particularly effective for neutralized concrete in that it is not destroyed by the chloride ions contained therein and does not disappear due to a decrease in pH. .

  As described above, the silane-based impregnated material 102 that has deeply penetrated remains in the concrete for a long period of time including the vicinity of the reinforcing bar, and is catalyzed by water, which is a typical reaction of the silane monomer. Dehydration can be continued and has the feature that water does not exist around the reinforcing bar. The silane polymer obtained by polymerizing the silane-based impregnating material 102 also has a property of preventing water from entering the inside of the concrete.

  On the other hand, as understood above, the silane-based impregnating material 102 polymerizes and reacts with hydroxyl groups (-OH) in concrete or on the surface of reinforcing steel to discharge water. According to the present invention, the water generated at this time is taken into the inorganic functional group of the silane coupling agent in the primer 103 to generate silanol, and reacts and bonds with the inorganic material, as described later. Improves adhesion with adhesives such as resin.

  In the present invention, as the silane-based impregnating material 102, the silane-based impregnating material disclosed in Patent Document 1 can be widely used. Next, the silane-based impregnating material that can be used in the present invention will be described.

Silane-based impregnating material The silane-based impregnating material (hereinafter also referred to as “drug”) that can be used in the present invention is represented by the general formula (II) as component A:
R-SiR ¹ _x (O) _y R ² _z (II)
[Where,
R represents a linear or branched alkyl group having 3 to 20 carbon atoms,
R ¹ represents a linear or branched alkyl group having 1 to 4 carbon atoms,
R ² represents a linear or branched alkoxy group having 1 to 4 carbon atoms or a hydroxy group, wherein the groups R ² may be the same or different Often,
x is 0, 1 or 2;
y is 0.0 to 1.5,
z is 0, 1, 2 or 3 and (x + 2y + z) = 3], and at least one organosilane or organosiloxane or a mixture thereof, and as component D, HO—CH ₂ —CH ₂ — Containing N (CH ₃ ) ₂ or HO—CH ₂ —CH ₂ —N (C ₂ H ₅ ) ₂ or a mixture thereof, and wherein component A and component D are 1: 1 to 26.2: 1 It is contained in a molar ratio.

The agent that may be used in the present invention, as component _{A, n-C 3 H 7} Si (OCH 3) 3, n-C 3 H 7 Si (OC 2 H 5) 3, i-C 3 H 7 Si ( _{OCH 3) 3, i-C} 3 H 7 Si (OC 2 H 5) 3, n-C 4 H 9 Si (OCH 3) 3, n-C 4 H 9 Si (OC 2 H 5) 3, i- _{C 4 H 9 Si (OCH 3} ) 3, i-C 4 H 9 Si (OC 2 H 5) 3, n-C 5 H 11 Si (OCH 3) 3, n-C 5 H 11 Si (OC 2 H _{5) 3, i-C 5} H 11 Si (OCH 3) 3, i-C 5 H 11 Si (OC 2 H 5) 3, n-C 6 H 13 Si (OCH 3) 3, n-C 6 H _{13 Si (OC 2 H 5)} 3, i-C 6 H 13 Si (OCH 3) 3, i-C 6 H 13 Si (O _{2 H 5) 3, n-} C 8 H 17 Si (OCH 3) 3, n-C 8 H 17 Si (OC 2 H 5) 3, i-C 8 H 17 Si (OCH 3) 3, i-C _{8 H 17 Si (OC 2 H} 5) 3, n-C 10 H 21 Si (OCH 3) 3, n-C 10 H 21 Si (OC 2 H 5) 3, i-C 10 H 21 Si (OCH 3 ) ₃ , i-C ₁₀ H ₂₁ Si (OC ₂ H ₅ ) ₃ , n-C ₁₆ H ₃₃ Si (OCH ₃ ) ₃ , n-C ₁₆ H ₃₃ Si (OC ₂ H ₅ ) ₃ , i-C ₁₆ H ₃₃ Si (OCH ₃ ) ₃ , i-C ₁₆ H ₃₃ Si (OC ₂ H ₅ ) ₃ or a partial condensate composed of one or more of the above-mentioned alkylalkoxysilanes, or a mixture or partial condensate composed of the above-mentioned alkylalkoxysilanes A mixture consisting of It can contain a mixture of an alkylalkoxysilane and a partial condensate.

  The agent may contain as component C dinonylnaphthalenesulfonic acid or an alkaline earth metal salt thereof or a mixture thereof.

  The above-mentioned drug can contain component C in an amount of 0 to 50% by mass relative to component A.

  The above-mentioned drug can contain component C in an amount of 0.01 to 10% by mass relative to component A.

  The above-mentioned drug can contain component C in an amount of 0.5 to 5% by mass relative to component A.

  The drug may contain as additional ingredients diisotridecyl adipate, mineral oil, benzene hydrocarbons, alcohols, rheology aids, thickeners or mixtures thereof.

The above-mentioned agent which can be used in the present invention will be further described. The agent which can be used in the present invention and protects reinforced concrete from corrosion of reinforcing bars is, as described above, a component A represented by the general formula (II):
R-SiR ¹ _x (O) _y R ² _z (II)
[Where,
R represents a linear or branched alkyl group having 3 to 20 carbon atoms,
R ¹ represents a linear or branched alkyl group having 1 to 4 carbon atoms,
R ² represents a linear or branched alkoxy group having 1 to 4 carbon atoms or a hydroxy group, wherein the groups R ² may be the same or different Often,
x is 0, 1 or 2;
y is 0.0 to 1.5,
z is 0, 1, 2, or 3, and (x + 2y + z) = 3]. at least one organosilane or organosiloxane or a mixture thereof.

  The application of agents based on alkylalkoxysilanes or alkylalkoxysiloxanes leads to a clear reduction of the corrosion current measured in the rebar, even if the concrete has already been damaged by invading chloride.

  In addition, certain organofunctional silanes and / or siloxanes, i.e. the aforementioned alkylalkoxysilanes or alkylalkoxysiloxanes, are compounds having amino groups, which may optionally be soluble in the alkylalkoxysilane or alkylalkoxysiloxane. Carboxylic acids or salts of carboxylic acids, preferably in combination with certain aminosilanes or certain amino alcohols and optionally in alkylalkoxysilanes or alkylalkoxysiloxanes, preferably dinonylnaphthalenesulfonic acid or alkaline earth metal salts Especially in combination with calcium dinonylnaphthalenesulfonate or magnesium dinonylnaphthalenesulfonate, or corresponding soluble inorganic salts, By acting on the surface of the building material, it is possible to continuously prevent corrosion current in reinforcing bars, it is also an existing, for example, can even been initiated corrosion is drastically reduced by chloride.

  Preference is given here to alkylalkoxysilanes or alkylalkoxysiloxanes having a particularly low chloride content. Said silanes or siloxanes having a chloride content of preferably less than 100 ppm by weight, particularly preferably less than 50 ppm by weight, particularly preferably less than 10 ppm by weight, are used. use. Excellent results can be achieved, in particular, when using substantially chloride-free alkylalkoxysilanes or alkylalkoxysiloxanes, ie silane products having less than 3 ppm by weight of chloride.

  Advantageously, the reduction in corrosion current observed in the rebar is at least 50%, preferably at least 80%, particularly preferably at least 90%, for the corresponding unprotected concrete.

  The high corrosion protection determined by measuring the corrosion current is achieved by the use of alkylalkoxysilanes and / or alkylalkoxysiloxanes, preferably isobutyltriethoxysilane, octyltriethoxysilane or low-viscosity propylethoxysiloxane, possibly with compounds containing amino groups. For example, aminosilanes, preferably aminopropyltriethoxysilane, or aminoalcohols which are miscible with the silane system used, preferably diethylaminoethanol, and / or optionally long-chain carboxylic acids or carboxylic acids. This is achieved in admixture with the calcium or magnesium salt of the acid, preferably calcium dinonylnaphthalenesulfonate, and optionally with the addition of other components such as solvents or processing aids.

  In general, the agents are mixed well with the components or stirred together, for example by means of the aforementioned organosilanes or organosiloxanes and optionally other active substances or active substance combinations and optionally diluents or optionally rheology modifiers. By adding, it can be produced in a simple and economical way. In the mixing step, any slight turbidity that may occur is usually filtered off.

  The drug or at least one active substance contained in the drug is advantageously of low viscosity and has good permeability. Advantageously, the medicament or at least one active substance contained therein, for example a compound of the general formula (II) or a corresponding active substance combination, is from 0.8 to 20 mPas, particularly preferably 1 to 20 mPas. It has a viscosity of 0.0 to 10 mPas.

  In order to improve the application properties, the abovementioned agents may be prepared by known methods as aqueous, low-viscosity or high-viscosity emulsions, in which case the viscosity of the active ingredient composition, i.e. Does not change. In this case, the preparation of the active ingredients as aqueous emulsions is advantageous, in order to ensure a dispersion that is as homogeneous as possible.

  The above-mentioned agents are, in addition to the active ingredient, additional components such as solvents, diluents or solubilizers, for example mineral oils, benzene hydrocarbons, alcohols, in particular methanol, ethanol, n-propanol, i-propanol, n-butanol, i-butanol. Butanol, s-butanol, t-butanol, further diisotridecyl adipate, water, emulsifier, rheology modifier, optionally also thickening aids, such as finely divided clay, precipitated silica, pyrogenic silica, or the corresponding May be contained.

Therefore, the feature of the above-mentioned agent for protecting reinforced concrete from corrosion of reinforcing bars is that, as described above, the agent is a corrosion-inhibiting component A represented by the following general formula (II):
R-SiR ¹ _x (O) _y R ² _z (II)
[Where,
R represents a linear or branched alkyl group having 3 to 20 carbon atoms,
R ¹ represents a linear or branched alkyl group having 1 to 4 carbon atoms,
R ² represents a linear or branched alkoxy group having 1 to 4 carbon atoms or a hydroxy group, wherein the groups R ² may be the same or different Often,
x is 0, 1 or 2;
y is 0.0 to 1.5,
z is 0, 1, 2 or 3, and (x + 2y + z) = 3]
At least one organosilane or organosiloxane of the formula (1) or a mixture thereof.

  Preferred partial condensates based on organosilanes, ie the organosiloxanes of the general formula (II), are known, for example, from DE 100 56 344 and DE 100 56 343.

  In the present invention, as the silane-based impregnating material, the above-mentioned organosilane or organosiloxane of the general formula (II) can be suitably used to protect reinforced concrete from corrosion of reinforcing steel. Further, the above-mentioned drug has excellent storage stability.

The application of the above-mentioned agents from a low-viscosity form to a high-viscosity form, ie in the form of a paste, or additionally in an emulsified form, can advantageously be carried out by spraying, brushing, rolling or knife coating. . In this case, the agent is suitably applied to the concrete surface in an amount of more than 50 g / m ² , preferably more than 100 g / m ² , particularly preferably more than 200 g / m ² . In some cases, especially if the desired amount of active substance cannot be applied in a single operation step, especially on the basis of the negligible absorbency of the support, for example from 2 hours to about 2 hours during the operation step It is also possible to apply a plurality of times with a drying period of days.

  Alkylalkoxysilanes or siloxanes are commonly used to impregnate (hydrophobize) porous inorganic building materials. In this case, the purpose of this measure is to block water and harmful substances dissolved in water, such as chlorides. In contrast, in the case of the present invention, it is surprising and advantageous to use a special alkylalkoxysilane or alkylalkoxysiloxane-containing agent to ascertain based on corrosion currents in reinforcing bars in cement-bonded inorganic building materials. It has been found that possible corrosion can be significantly reduced, in particular the existing corrosion can be stopped or at least effectively mitigated by using the agents according to the invention.

Furthermore, the application of a liquid inhibitor system, which can be used according to the invention, on the concrete surface significantly reduces the corrosion current in the rebar, both in the presence of existing corrosion and in the case of concrete damaged by cracks. It turns out that it can be done. The liquid inhibitor preparation can be applied directly on the concrete surface. As a method of application, known methods such as spray application, spray application, flow application, roll application, and brush application are suitable. The inhibitor preparations can be prepared as emulsions by methods known per se and applied accordingly. It is appropriate to apply such an emulsion to the concrete surface by the known method described above, in which case a paste-like, high-viscosity emulsion can also be knife-coated. Normally, care must be taken to ensure that a sufficient amount of product can penetrate into the concrete in order to achieve a sufficient protective effect. Sufficient protection is generally achieved when the measurable corrosion current is reduced by more than 80% relative to the unprotected surface. Such a protective effect is usually achieved by the inhibitor system according to the invention when the coating weight is advantageously greater than 200 g / m ² . In this case, it should generally be ensured that all the applied material penetrates into the concrete. It is advisable to apply several times or to apply a product according to the invention with a high viscosity, for example a paste-like emulsion, or an inhibitor thickened by a rheology modifier. Suitable for thickening the inhibitor are, for example, finely divided solids, such as fumed silica, fumed silica or finely divided clay minerals, such as kaolin. When using the high-viscosity drug according to the invention, 200 g / m ² can be applied in a single working step, even on vertical surfaces, without too much product loss due to sagging.

  Here, the preparation and application of the silane-based impregnating material that can be used in the present invention will be described.

The alkylalkoxysilane and the corresponding siloxane are optionally mixed with an amino-functional compound and a carboxylic acid or a salt of a carboxylic acid. The resulting mixture is single phase. If necessary, stirring and heating are carried out additionally. Mixing times of from 1 minute to several hours have been found to be advantageous in the temperature range from 20 ° C. to the point at which the alkylalkoxysilane or alkylalkoxysiloxane mixture begins to boil (up to about 180 ° C.). At that time, a chemical reaction may proceed. Here are some examples:
R-Si (OR ¹ ) ₃ + n (C ₂ H ₅ ) NC ₂ H ₄ OH
→ R-Si (OR ¹ ) _3-n [(C ₂ H ₅ ) NC ₂ H ₄ O] _n + nR ¹ OH
R-Si (OR ¹ ) ₃ + nR ² COOH
→ R-Si (OR ¹ ) _3-n (R ² COO) _n R ¹ OH
The resulting single-phase mixture is usually liquid and of low viscosity (viscosity is usually <10 mPas, for example <5 mPas, in particular <1.5 mPas). A solvent can additionally be used to adjust the viscosity. Suitable solvents are, for example, alcohols, preferably ethanol, methanol or isopropanol or benzene hydrocarbons, for example petroleum benzene or solvent kerosene. The liquid inhibitor mixture is applied directly to the concrete surface or is prepared in a known manner as an oil-in-water emulsion and applied in the form of an aqueous emulsion onto the concrete surface. In the case of aqueous emulsions, besides low-viscosity emulsions, high-viscosity emulsions can also be applied. In some cases, highly viscous emulsions are advantageous. This is especially the case when high product quantities are to be applied in the application step. What is important for the process described is that a sufficient amount of active substance (not solvent, but not a continuous phase in the case of emulsion = water) penetrates into the concrete. To achieve this, multiple applications have proven to be advantageous. That is, applying the inhibitor preparation to the concrete surface multiple times. In this case, attention should be paid to the measured drying time. The surface must be at least dry in appearance before starting the next application. This procedure is repeated until the desired amount of product has been absorbed by the support (concrete). In the case of ordinary concrete, one to six applications are required in order to absorb at least 150 g / m ² of the total amount of inhibitor active substance in the field. The number of individual applications depends on the porosity of the concrete. The denser the concrete, the more individual applications are required. The porosity of the binder phase of concrete is characterized by the water / cement ratio (w / c). The lower the w / c ratio, the denser the binder phase of the concrete. Particular preference is given to absorption of the active ingredient above 200 g / m ² , particularly preferably to absorption of the active ingredient above 400 g / m ² .

  As described above, according to the present invention, the above-mentioned chemical, that is, the silane-based impregnating material 102 is applied to the reinforced surface 101 of the reinforced concrete structure 100.

(3rd step)
After the silane-based impregnating material 102 is applied to the reinforced surface 101 of the reinforced concrete structure 100 in the second step, for example, 30 to 60 minutes elapse, the silane-based impregnating material 102 moves from the structure surface 101 to the inside. And the surface of the structure becomes dry to the touch. Preferably, after further curing for several hours, for example, about 4 hours, a primer 103 is applied to the surface 101 of the structure using an appropriate application means such as a spatula, a trowel or a roller to form a primer layer 104 ( FIG. 7 (c)). Next, the primer 103 used in the present invention will be described.

Primer In the present invention, the primer 103 is a two-component epoxy resin-based primer containing an epoxy resin as a main agent and a curing agent such as a diamine, such as an epoxy resin primer. Further, the primer 103 of the present invention contains a silane coupling agent, and its content is 0.1 to 5.0% by weight, preferably 1.0 to 3.0% by weight. If the content of the silane coupling agent exceeds 5.0% by weight, the effect of the coupling agent is more unfavorable because the influence on the decrease in the hardness of the epoxy resin and the like is more unfavorable. Further, although the effect of the coupling agent can be obtained with a small amount, when the content of the coupling agent is less than 0.1% by weight, the silane-based impregnating material 102 is applied, which is affected by moisture which is volatilized thereafter, and 103 does not show effective adhesion performance to concrete.

  Further, preferably, the primer 103 of the present invention can include a filler. The content is 0.1 to 10% by weight, preferably 5.0 to 8.0% by weight. If the content of the filler is more than 10% by weight, the workability is lowered, and only the liquid resin component of the primer 103 is impregnated into the concrete surface, and only the filler is separated, which is unsuitable because it changes the performance of the epoxy resin. It is. Further, although the effect can be obtained even with a small amount of the filler, if the content of the filler is less than 0.1% by weight, it is difficult to ensure the wettability with the concrete surface and the appropriate film thickness. Next, the silane coupling agent and the filler will be described in more detail.

-Silane coupling agent As the silane coupling agent to be mixed with the primer 103 used in the present invention, those well known to those skilled in the art can be used. That is, the main component of the silane coupling agent is represented by the following general formula (I),
Y-Si- (OX) ₃ (I)
here,
Y is an organic functional group that reacts with an organic material, and is an amino group, a mercapto group, a vinyl group, or an epoxy group;
OX is an inorganic functional group that reacts with the inorganic material, and is an alkoxy group.
It is an organosilicon compound. Further, if necessary, other components can be contained, but a 100% pure silane coupling agent can also be used.

  In the present invention, as will be described in detail later, since the epoxy resin is generally widely used as the adhesive 105, it is not limited. However, the primer 103 is preferably an epoxy resin-based primer. As the functional group (Y), an epoxysilane-based silane coupling material having an epoxy group is preferably used.

  That is, the silane coupling agent mixed with the primer 103 is preferably 3-glycidoxypropyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, or 3-glycidoxypropylmethyldimethoxysilane. It is silane, 3-glycidoxypropylmethyldiethoxysilane, or 3-glycidoxypropyltriethoxysilane.

-Filler As understood above, the silane-based impregnating material 102 polymerizes and reacts with hydroxyl groups (-OH) in concrete or on the surface of reinforcing steel to discharge water. According to the present invention, the water generated at this time is taken in by the inorganic functional group of the silane coupling agent in the primer 103 to generate silanol, and reacts and bonds with the inorganic material, and an adhesive such as an epoxy resin. Improve adhesion with

  In addition, preferably, as described above, in the present invention, the primer 103 can prevent repelling by moisture by including a filler. Therefore, according to the present invention, even when the silane-based impregnating material, which is an aqueous composition, is applied, the primer 103 can be applied several hours after the silane-based impregnating material is applied. The bonding step can be performed, and a conventionally required curing time of, for example, 24 hours or more after application of the silane-based impregnating material is not required. That is, by applying the primer 103 containing the silane coupling agent and the filler, the adhesive performance between the fiber sheet and the surface of the concrete structure by the adhesive 105 does not decrease. This has been experimentally verified by test methods specified in the Japan Society of Civil Engineers and JIS, as shown in the experimental examples described later.

  The filler mixed in the primer 103 of the present invention is a powdery filler having an average particle diameter of, for example, 10 to 20 μm, such as silica powder, calcium carbonate powder, titanium oxide powder, and ceramic powder.

  According to the reinforcing method of the present invention using the primer 103 having the above composition, it is possible to apply a silane-based impregnating material capable of suppressing corrosion of a reinforcing bar of a reinforced concrete structure, and to be used in the next step. It acts on the organic resin material (adhesive) and the inorganic material such as concrete, which is the construction surface, to realize the strong bonding of the fiber sheet 1 to the concrete structure and improve the adhesive performance.

The application amount of the primer 103 is 0.15 to 0.30 kg / m ² .

  The primer 103 applied to the surface 101 to be bonded of the concrete structure as described above does not need to wait for the primer layer 104 to completely dry, and immediately after application, for example, after application of the primer 103 After a lapse of 2 to 3 hours, that is, immediately after the touch drying, the next step can be performed. Conventionally, in the rust-prevention work of the reinforcing bar by applying the silane-based impregnating material, after applying the silane-based impregnating material, it is necessary to cure for at least 24 hours before drying. The shortening of the time until the next step (fiber sheet bonding step) after the step of applying the silane-based impregnating material and the primer is also one of the features of the present invention, and the entire reinforcing work step can be significantly reduced.

  In addition, if necessary, when the ground surface (the surface 101 to be reinforced) requires unevenness correction, the unevenness correcting material 106 can be applied on the primer layer 104. The unevenness correction material 106 is formed, for example, by applying a putty-like epoxy resin adhesive to a required area, not necessarily the entire area to be reinforced, with a required thickness, for example, 0.5 mm to 10 mm. can do.

(3rd step)
As shown in FIGS. 7C and 7D, when a primer 103 is formed on the surface 101 to be reinforced by applying the primer 103 to the surface 101 to be reinforced of the reinforced concrete structure. The adhesive 105 is applied on the upper surface, and the fiber sheet 1 is pressed against this surface to adhere to the surface 101 of the concrete structure 100 to be reinforced.

  Examples of the adhesive 105 include a cold-setting epoxy resin, an epoxy acrylate resin, an acrylic resin, an MMA resin, a vinyl ester resin, an unsaturated polyester resin, and a light-curing resin. Specifically, a cold-setting epoxy resin is used. It is preferably used.

The epoxy resin adhesive used in the present embodiment is provided by a two-component type of a main agent and a curing agent, and the following is an example of the composition.
(I) Main agent: A material containing an epoxy resin as a main component and a silane coupling agent as needed as an adhesion-enhancing agent is used. The epoxy resin may be, for example, a bisphenol-type epoxy resin, particularly a rubber-modified epoxy resin for imparting toughness, and a reactive diluent and a thixotropic agent may be added according to the application.
(Ii) Curing agent: A compound containing amines as a main component, a curing accelerator as needed, and a colorant as an additive is used, and an epichlorohydrin as a main component: an amine equivalent ratio of a curing agent is 1: It is one. The amines can be, for example, aliphatic amines including meta-xylene diamine and isophorone diamine.

  Although the adhesive 105 has been described as being applied on the primer layer 104, it can be applied to the fiber sheet 1, and of course, the adhesive 105 may be applied on both the surface of the primer layer 104 and the adhesive surface of the fiber sheet 1. It may be applied.

  That is, in the present embodiment, the fiber sheet 1 is bonded to the surface of the primer layer 104, and when the fiber sheet 1C (the fiber sheet described as the specific example 3 shown in FIG. 4) is used in the present embodiment. Is filled with a resin in the gap (g) between the wires 2 and 2. In some cases, for example, in the case of the fiber sheet 1A shown in the specific example 1, as described above, the adhesive 105 is used. Is impregnated between the fibers f in the fiber sheet 1 as a resin (matrix resin).

  Next, the following experiment was conducted to demonstrate the effect of the method for reinforcing a concrete structure according to the present invention.

Experimental example 1 (shear adhesion test)
In this experimental example, as shown in FIG. 9, the fiber sheet 1 was bonded to a concrete test specimen 100T according to a bonding method, and a shear adhesion test was performed.

  The shear adhesion test between the concrete structure and the fiber sheet 1 is performed in accordance with JSCE-543-2012 “Adhesion strength test between continuous fiber sheet and concrete” specified by the Japan Society of Civil Engineers. , Effective adhesion length (Le) was determined, and its validity was evaluated in applying the method of the present invention.

(Experimental specimen)
FIGS. 9A, 9B, and 9C schematically show the shape and dimensions of the test specimen 100T. The test specimen is an integral type (B-type specimen) that is unlikely to shift during construction, hits the notch portion 100T1 before loading, and sets the concrete on the anchoring side (left side in FIGS. 9A and 9B). And the test side (right side in FIGS. 9A and 9B). For loading, an Instron type universal testing machine (maximum load 100 kN) was used. The screw portions 100T2 at both ends of the test piece were fastened and fixed with a special jig, and the test piece was loaded and evaluated by applying a tensile load.

  In this experimental example, a carbon fiber sheet is wound around and fixed to a region on the fixing side of the test specimen 100T around the notch portion 100T1, and the carbon fiber sheet 1 in a region on the test side of the test specimen 100T is fixed. And the state of adhesion between the sample and the specimen 100T were observed.

  The measurement was made into load, displacement, and strain, and the potential difference between the load cell of the tester and the wire strain gauge was recorded synchronously with a data logger.

  Table 1 shows a list of materials used in the test.

-Fiber sheet In this experimental example, the fiber sheet 1 was the carbon fiber sheet 1A having the configuration described as the specific example 1 with reference to Fig. 2, that is, the carbon fiber sheet 1A in which the carbon fibers f were arranged in one direction. The fiber sheet 1 used in this experimental example is a high-strength carbon fiber sheet (trade name) manufactured by Nippon Steel & Sumitomo Metal Materials Co., Ltd. using PAN-based carbon fibers having an average diameter of 7 μm and a convergence number of 24,000 as the reinforcing fibers f. : Tow sheet FTS-C1-20) was used. The fiber basis weight was 1.0 kg / m ² .

Silane-based impregnating material As the silane-based impregnating material 102, a silane-based impregnating material manufactured by Evonik Debsa GmbH GmbH (product name: "Protectyl CIT") containing isobutyltriethoxysilane and diethanolamine as main components was used. .

  The silane-based impregnating material 102 was prepared by mixing 980 g of isobutyltriethoxysilane and 20 g of diethanolamine and stirring at 40 ° C. for 30 minutes, and the product had a viscosity of 1 mPas.

-Primer In this experimental example, as the primer 103, an epoxy resin primer, a wet surface epoxy resin (trade name: FP-Si7) manufactured by Nippon Steel & Sumikin Materials Co., Ltd. was used. This epoxy resin primer is a two-component epoxy resin primer containing an epoxy resin as a main component and a curing agent to be an aliphatic amine, having a silane coupling agent of 3% by weight and a filler having an average particle diameter of 16 μm. It contained 8% by weight of titanium oxide powder.

  The silane coupling agent mixed in the primer 103 is a silane coupling agent manufactured by Shin-Etsu Chemical Co., Ltd. (trade name: KBM-403) containing 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane as a main component. The agent was used.

(Test method)
First, in this experimental example, the surface 101 to be bonded of the specimen 100T was subjected to a base treatment using a disk sander to remove an oil film, dirt, and the like adhering to the surface 101 to be bonded. 0.528 kg / m ² of the silane-based impregnating material 102 was applied to the surface 101 of the test sample 100T by roller application.

The silane-based impregnating material 102 was applied under two conditions of curing for 4 hours in a 5 ° C. environment and curing for 15 hours in a 23 ° C. environment. After the curing time had elapsed, the epoxy resin primer 103 was applied at a rate of 0.2 kg / m ² using a roller brush (the applied thickness T was approximately 0.17 mm).

In this experimental example, after the primer 103 was applied, after the primer layer 104 was touch-dried, the unevenness correcting material 106 was applied onto the primer layer 104 using a spatula. An epoxy resin putty material (trade name: FE-Z) manufactured by Nippon Steel & Sumikin Materials Co., Ltd. was used as the unevenness correction material. In this experimental example, the epoxy resin putty material was applied at 1.3 kg / m ² (0.8 mm in thickness).

After applying the unevenness correction material 106, wait for the unevenness correction material to dry to the touch, and then apply an epoxy resin 105 as an impregnating adhesive 105 on the unevenness correction material layer at a coating amount of 0.6 kg / m ^2. Was applied.

  In this experimental example, the epoxy resin 105 (trade name: FR-E3P) manufactured by Nippon Steel & Sumikin Materials Co., Ltd. was used as the epoxy resin 105 as the impregnating adhesive.

  Next, after lightly pressing the carbon fiber sheet 1 against the epoxy resin coated surface, the carbon fiber sheet 1 was moved while applying pressure to the plastic roller on the carbon fiber sheet 1. The epoxy resin was in a state of seeping out from the fiber sheet 1, and the epoxy resin was evenly leveled by a roller, so that the fiber sheet 1 could be completely bonded to the concrete specimen 100T.

  After adhering the carbon fiber sheet 1 to the specimen 100T, the carbon fiber sheet 1 was left to cure at room temperature (23 ° C.) for 22 days and subjected to the test. The results of the shear adhesion test are shown in Table 2 below. The test was completed in a state where the concrete cover portion adhered to the carbon fiber sheet in all the test specimens 100T. These are judged to be normal peeling failure situations. FIGS. 10 (1) to 10 (5) show the state of peeling failure of the test piece 100T.

  According to the above experiment, the wet bonding type epoxy primer 103 is applied to the concrete structure 100T to which the silane-based impregnating material 102 is applied in advance, which is provided by the reinforcing method of the present invention, and an epoxy resin putty (if necessary) The reinforcing structure used for applying the fiber sheet 1 having reinforcing fibers such as carbon fibers in a series of flows with the applied non-land correction material 106 and the epoxy resin impregnated adhesive 105, and a reinforcing structure used for earthquake-resistant reinforcement, etc. It was confirmed that it conformed to.

In other words, the experimental results show that the method according to the present invention exceeds the shear bond strength characteristic value of 0.44 N / mm ² or more used in the existing design method for all the specimens and has an effective shear bond characteristic value. confirmed. In addition, all specimens exceeded the interface peeling fracture energy 0.5 N / mm specified by the Japan Society of Civil Engineers, and it was confirmed that the existing design method could be used.

  In addition, "effective adhesion length (Le)" means the length of the section where the adhesion stress between the fiber sheet and concrete is effectively acting at the maximum load until the continuous fiber sheet is peeled off.

  From the test results, according to the method of the present invention, an effective adhesion length of about 91 mm was achieved in an environment such as a 5 ° C. environment and a 4-hour curing, and an effective adhesion length in an environment such as a 23 ° C. environment and a 15-hour curing. It can be seen that performance exceeding the adhesion length (average value) of 80 mm was achieved.

Experimental example 3 (kenken type adhesion test)
In this experimental example, an evaluation test of the adhesion performance between the concrete structure 100 reinforced according to the present invention and the fiber sheet 1 was performed in accordance with the Kenken-type test specified in JIS A 6909.

  FIGS. 11A and 11B schematically show the shape, dimensions, and adhesion test method of the concrete structure test specimen 100T. As shown in FIG. 11A, the test specimen 100T had a length (L0) of 300 mm, a width (W0) of 300 mm, and a height (H0) of 60 mm.

  According to the present invention, a silane-based impregnating material 102 and a primer 103 were applied to one side surface of the test specimen 100T according to the present invention using the same material and the same construction method as those of the above-mentioned Experimental Example 1 shown in Table 1 above. The fiber sheet 1 was adhered with the adhesive 105 via the modifying material (putty material) 106.

However, after the silane-based impregnating material 102 was applied to the test specimen 100T at 0.528 kg / m ^2, it was cured for 24 hours in a 20 ° C. environment, and was cured for 0.5 hours in a 5 ° C. environment. For 4 hours curing.

  Next, as shown in FIG. 11C, a steel attachment (jig) 120 having a length and width of (L1) 40 mm × (W1) 40 mm was bonded to the fiber sheet 1 with an adhesive 121. Thereafter, the steel attachment 120 was pulled upward, and the materials in the specimen and the destruction state in the turning surface were observed to evaluate the adhesion performance. Table 3 shows the results.

  From the test results, the failure mode was concrete failure or attachment adhesive 121 failure. That is, in any of the test specimens, there was no peeling between the surface 101 of the test specimen coated with and impregnated with the cyan-based impregnating material 102 and the primer layer 104, and according to the present invention, the cyan-based impregnating material was used. It was found that there was no decrease in adhesion strength due to application to the concrete structure in advance and impregnation.

1 Fiber Sheet 100 Reinforced Concrete Structure 100T Experimental Specimen 101 Reinforced Surface 102 Cyan Impregnating Material 103 Primer 104 Primer Layer 105 Adhesive

Claims (19)

In a method for reinforcing a reinforced concrete structure in which a fiber sheet containing a reinforcing fiber is bonded and integrated,
(A) applying a silane-based impregnating material to the surface of the reinforced concrete structure;
(B) applying a primer containing a silane coupling agent to the surface of the reinforced concrete structure to which the silane-based impregnating material has been applied, to form a primer layer;
(C) adhering the fiber sheet to the surface of the reinforced concrete structure on which the primer layer is formed, with an adhesive;
A method for reinforcing a reinforced concrete structure, comprising:   The method for reinforcing a reinforced concrete structure according to claim 1, wherein the content of the silane coupling agent in the primer is 0.1 to 5.0% by weight.   The method for reinforcing a reinforced concrete structure according to claim 1, wherein the primer further contains 0.1 to 10% by weight of a powdery filler. The main component of the silane coupling agent is represented by the following general formula (I),
Y-Si- (OX) ₃ (I)
here,
Y is an organic functional group capable of reacting and bonding with an organic material,
OX is an inorganic functional group that reacts with the inorganic material,
The method for reinforcing a reinforced concrete structure according to any one of claims 1 to 3, wherein the method is an organosilicon compound. The organic functional group is an amino group, a mercapto group, a vinyl group, or an epoxy group,
The inorganic functional group is an alkoxy group,
The method for reinforcing a reinforced concrete structure according to claim 4, wherein:   The silane coupling agent includes 3-glycidoxypropyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, and 3-glycidoxypropylmethyldimethoxysilane. The method for reinforcing a reinforced concrete structure according to any one of claims 1 to 3, wherein the method is ethoxysilane or 3-glycidoxypropyltriethoxysilane. The silane-based impregnating material has a general formula (II) as component A
R-SiR ¹ _x (O) _y R ² _z (II)
[Where,
R represents a linear or branched alkyl group having 3 to 20 carbon atoms,
R ¹ represents a linear or branched alkyl group having 1 to 4 carbon atoms,
R ² represents a linear or branched alkoxy group having 1 to 4 carbon atoms or a hydroxy group, wherein the groups R ² may be the same or different Often,
x is 0, 1 or 2;
y is 0.0 to 1.5,
z is 0, 1, 2 or 3 and (x + 2y + z) = 3], and at least one organosilane or organosiloxane or a mixture thereof, and as component D, HO—CH ₂ —CH ₂ — Containing N (CH ₃ ) ₂ or HO—CH ₂ —CH ₂ —N (C ₂ H ₅ ) ₂ or a mixture thereof, and wherein component A and component D are 1: 1 to 26.2: 1 The method for reinforcing a reinforced concrete structure according to claim 1, wherein the reinforced concrete structure is contained in a molar ratio. The silane-based impregnant as component _{A, n-C 3 H 7} Si (OCH 3) 3, n-C 3 H 7 Si (OC 2 H 5) 3, i-C 3 H 7 Si (OCH 3) _{3, i-C 3 H 7} Si (OC 2 H 5) 3, n-C 4 H 9 Si (OCH 3) 3, n-C 4 H 9 Si (OC 2 H 5) 3, i-C 4 H _{9 Si (OCH 3) 3,} i-C 4 H 9 Si (OC 2 H 5) 3, n-C 5 H 11 Si (OCH 3) 3, n-C 5 H 11 Si (OC 2 H 5) 3 _{, i-C 5 H 11 Si} (OCH 3) 3, i-C 5 H 11 Si (OC 2 H 5) 3, n-C 6 H 13 Si (OCH 3) 3, n-C 6 H 13 Si ( _{OC 2 H 5) 3, i} -C 6 H 13 Si (OCH 3) 3, i-C 6 H 13 Si (OC 2 H _{) 3, n-C 8 H} 17 Si (OCH 3) 3, n-C 8 H 17 Si (OC 2 H 5) 3, i-C 8 H 17 Si (OCH 3) 3, i-C 8 H 17 _{Si (OC 2 H 5) 3} , n-C 10 H 21 Si (OCH 3) 3, n-C 10 H 21 Si (OC 2 H 5) 3, i-C 10 H 21 Si (OCH 3) 3, _{i-C 10 H 21 Si (} OC 2 H 5) 3, n-C 16 H 33 Si (OCH 3) 3, n-C 16 H 33 Si (OC 2 H 5) 3, i-C 16 H 33 Si (OCH ₃ ) ₃ , i-C ₁₆ H ₃₃ Si (OC ₂ H ₅ ) ₃ or a partial condensate composed of one or more of the above-mentioned alkylalkoxysilanes, a mixture composed of the alkylalkoxysilane, or a mixture composed of the partial condensates Or alkyl The method for reinforcing a reinforced concrete structure according to claim 7, comprising a mixture comprising an alkoxysilane and a partial condensate.   The method for reinforcing a reinforced concrete structure according to claim 7 or 8, wherein the silane-based impregnating material contains dinonylnaphthalenesulfonic acid, an alkaline earth metal salt thereof, or a mixture thereof as Component C.   The method for reinforcing a reinforced concrete structure according to claim 9, wherein the silane-based impregnating material contains Component C in an amount of 0 to 50% by mass with respect to Component A.   The method for reinforcing a reinforced concrete structure according to claim 10, wherein the silane-based impregnating material contains Component C in an amount of 0.01 to 10% by mass with respect to Component A.   The method for reinforcing a reinforced concrete structure according to claim 11, wherein the silane-based impregnating material contains component C in an amount of 0.5 to 5% by mass with respect to component A.   The silane-based impregnating material contains, as an additional component, diisotridecyl adipate, mineral oil, benzene hydrocarbon, alcohol, rheology aid, thickener, or a mixture thereof. The method for reinforcing a reinforced concrete structure according to any one of the above items.   The adhesive used in the step (b) is a cold-setting epoxy resin, an epoxy acrylate resin, an acrylic resin, an MMA resin, a vinyl ester resin, an unsaturated polyester resin, or a photo-curable resin. The method for reinforcing a reinforced concrete structure according to claim 1. The adhesive used in the step (b) is a cold-setting epoxy resin, and the epoxy resin adhesive is provided as a two-component type of a main agent and a curing agent,
(I) Main agent: An epoxy resin is used as a main component, and a silane coupling agent or the like is used as an adhesion enhancer if necessary.
(Ii) Curing agent: An amine is contained as a main component, and an amine equivalent ratio of each of an epoxy resin as a main component and a curing agent is 1: 1.
The method for reinforcing a reinforced concrete structure according to claim 1, wherein the method is a composition.   The reinforced concrete structure according to any one of claims 1 to 15, wherein the fiber sheet is a fiber sheet in which continuous reinforcing fibers aligned in one direction are fixed to each other with a wire fixing material. Reinforcement method.   The method according to claim 17, wherein the fiber sheet is a fiber sheet in which continuous reinforcing fibers are impregnated with a resin and the resin is cured.   The fiber sheet is a fiber sheet in which reinforcing fibers are impregnated with a matrix resin, a plurality of continuous hardened fiber-reinforced plastic wires are aligned in a longitudinal direction, and the wires are fixed to each other with a wire fixing material. The method for reinforcing a reinforced concrete structure according to any one of claims 1 to 15, wherein:   The reinforcing method of a reinforced concrete structure according to claim 18, wherein the fiber sheet is a fiber sheet in which a resin is impregnated between the fiber reinforced plastic wires and the resin is cured.