JP2018109268A - Method to reinforce concrete structure, concrete structure and flexible continuous fiber reinforcement material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method to reinforce a concrete structure that enables use of a long reinforcement material measuring 25 m or more, or 50 m or more if necessary, by using a belt-form flexible continuous fiber reinforcement material, at the same time eliminating a need on a lap joint and a concern over fatigue strength of a joint part, and furthermore allowing a depth of a cut groove formed on a concrete floor slab to be shallow, without a need on a complicated structure, and offering a sufficient effect even when a concrete surface has become brittle.SOLUTION: A flexible continuous fiber reinforcement material 10 hardens a resin inside a cut groove 30, is installed inside the narrow, linear cut groove 30 formed on a surface of a concrete structure 1 and contains a plurality of continuous reinforcement fibers and the not-yet-hardened resin. At the same time, the continuous fiber reinforcement material 10 made of an FRP material hardened inside the cut groove 30 is fixed to the cut groove 30 by a binder 40, thus fixing and integrating the continuous fiber reinforcement material 10 made of the FRP material with the concrete structure and thereby reinforcing the concrete structure.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a slab concrete structure (hereinafter simply referred to as a “concrete structure” or “a”) on a floor slab, a bottom surface, a beam, a bottom surface, a side surface, and a column in a civil engineering building structure such as a bridge or an elevated road. And the continuous fiber reinforcing material used in the reinforcing method of the concrete structure.

  Conventionally, as a method for reinforcing a concrete structure, for example, as a method for reinforcing a concrete floor slab structure such as a bridge or an elevated road, an upper surface thickening method, a steel plate bonding method, a continuous fiber sheet bonding method, or the like has been adopted. . Each of the reinforcing methods has a certain effect in improving the fatigue durability of the concrete slab, but has the following problems.

  In other words, the top surface thickening method requires a road closure for reinforcement work, the floor slab weight increases, and there is a possibility of peeling from the existing floor slab concrete.

  The steel plate bonding method requires periodic repainting because the reinforcing steel plate is corroded, and if the deterioration progresses and there is water leakage from cracks in the floor slab concrete, the steel plate on the bonding surface will corrode and peel off. Easy to progress. The deterioration of the floor slab cannot be observed because it covers the entire lower surface of the floor slab.

  The continuous fiber sheet bonding method does not corrode the continuous fiber sheet, but when bonded to the entire floor slab, water leakage from cracks in the floor slab concrete stagnates in the concrete as well as steel sheet bonding, promoting deterioration of the concrete, It causes peeling of the continuous fiber sheet and concrete.

  Therefore, a concrete reinforcing method for solving the above problem has been proposed. However, in Patent Document 1, a groove is formed so as to cross a part of the crack in the cover portion of the lower surface of the concrete where the crack is generated on the lower surface. A method for reinforcing concrete is described in which a reinforcing fiber reinforced plastic rod is embedded through a filler, such as an epoxy putty, which is formed and has an adhesive strength that does not spread over the entire crack in the groove.

  Further, in Patent Document 2, a cutting groove is formed by attaching a concrete surface of a road side belt portion of a road bridge deck that is a concrete structure, and a fiber having an elastic modulus of 100 to 1000 GPa is formed in the cutting groove. An FRP reinforcing method for a road bridge deck is described in which a reinforcing bar of fiber reinforced plastic is arranged and then a resin mortar is placed in a cutting groove.

Japanese Patent No. 4084618 Japanese Patent No. 3877145

  However, in any of the concrete reinforcing methods described in Patent Documents 1 and 2, as a reinforcing material, a reinforcing rod such as carbon fiber is impregnated with a resin and cured, for example, a round rod (rod) having a diameter of 5 to 15 mm. Material) and such rods are not flexible and cannot be rolled and transported. For example, it is impossible or difficult to transport a long rod of 10 m or more. Accompanied. Therefore, the rod length is usually about 3 to 4 m that can be transported by a vehicle. Therefore, in the reinforcement of a floor slab using such a rod, when a rod having a length of 3 to 4 m is arranged in the bridge axis direction, it is necessary to install a rod having a length of 3 or 4 m while providing a lap joint. It is said. In order to provide a lap joint in the existing floor slab concrete, it is necessary to devise the arrangement of shifting the cutting groove for installing the rod or widening the groove width, and the structure must be complicated. Is done. Furthermore, at present, the fatigue strength of the joint has not been confirmed.

  Therefore, the present inventors, in the process of studying a method for reinforcing a concrete structure such as a concrete floor slab, used a conventional reinforcing fiber such as carbon fiber impregnated with a resin as a reinforcing material. As a result of many researches and experiments, the inventors came up with the idea of using the continuous fiber reinforcing material having flexibility instead of using a non-flexible rod. .

  In other words, if it is a continuous fiber reinforcing material having flexibility, it is possible to use a reinforcing material having a length of 25 m or more, and if necessary, a long reinforcing material of 50 m or more by forming a roll shape at the time of transportation, and a lap joint is required. It can be installed continuously in the direction of the bridge axis. In addition, by using a continuous fiber reinforcing material having flexibility, even when a continuous fiber reinforcing material is arranged in two directions, the continuous fiber reinforcing material can be crushed and arranged at the intersection, and the conventional curing is performed. The groove depth for installing the continuous fiber reinforcing material can be made shallower than when using a rod (bar material) that does not have flexibility. The present invention is based on such novel findings of the present inventors.

  The main purpose of the present invention is to make it possible to visually recognize the surface of the concrete structure without covering most of the surface of the concrete structure, to visually check the deterioration state of the concrete structure and to prevent water in the concrete structure. It is to provide a method for reinforcing a concrete structure, a concrete structure reinforced by such a reinforcing method, and a flexible continuous fiber reinforcing material used in such a reinforcing method.

  Another object of the present invention is to use a continuous reinforcing material having flexibility, and it is possible to use a reinforcing material having a length of 25 m or more, and if necessary, a length of 50 m or more. No need to worry about the fatigue strength of the joint, and even when providing a joint, it is possible to reduce the number of joints by using a long continuous fiber reinforcement compared to the FRP rod. The time can be shortened, and further, the depth of the cutting groove formed in the concrete structure can be reduced, so that a complicated structure is not required and even if the surface of the concrete is weak, it is sufficient. An object of the present invention is to provide a method for reinforcing a concrete structure that can provide an effect.

  Furthermore, an object of the present invention is to provide a method for reinforcing a concrete structure which can remarkably improve workability and handling by using a continuous fiber reinforcing material having flexibility, and can shorten the work time. Is to provide.

The above object is achieved by the method for reinforcing a concrete structure, the concrete structure and the flexible continuous fiber reinforcing material according to the present invention. In summary, the present invention relates to a flexible continuous fiber having a large number of continuous reinforcing fibers and an uncured resin installed in a narrow line-shaped cutting groove formed on the surface of a concrete structure. The reinforcing material is cured in the resin in the cutting groove, and the continuous fiber reinforcing material cured in the cutting groove is fixed in the cutting groove with an adhesive.
This is a method for reinforcing a concrete structure.

According to one aspect of the present invention, at least one narrow linear cutting groove is provided on the surface of the concrete structure,
The resin is impregnated with a flexible dry continuous fiber reinforcing material not impregnated with resin, and is pushed into the cutting groove and installed, and by curing the resin, the resin functions as a fixing agent, Fixing the continuous fiber reinforcement in the cutting groove;
A method for reinforcing a concrete structure is provided.

According to another aspect of the present invention, at least one narrow linear cutting groove is provided on the surface of the concrete structure,
A flexible dry continuous fiber reinforcing material not impregnated with resin is installed in the cutting groove, and then the resin is injected into the cutting groove to impregnate the continuous fiber reinforcing material with the resin. By curing, the resin functions as a fixing agent, and the continuous fiber reinforcing material is fixed in the cutting groove.
A method for reinforcing a concrete structure is provided. Here, according to one embodiment, when the cutting groove is formed on a lower surface or a side surface of the concrete structure, after the dry continuous fiber reinforcing material is installed in the cutting groove, the The opening of the cutting groove is covered with a lid member, and the resin is injected into the cutting groove from a resin injection port provided in the lid member.

According to another aspect of the present invention, at least one narrow linear cutting groove is provided on the surface of the concrete structure,
Pre-applying a sticking agent in the cutting groove,
Before the fixing agent is cured, the resin is impregnated with a flexible dry continuous fiber reinforcing material that is not impregnated with the resin, and is pushed into a cutting groove to which the fixing agent is applied. By fixing the fixing agent, the continuous fiber reinforcing material is fixed in the cutting groove,
A method for reinforcing a concrete structure is provided.

According to another aspect of the present invention, at least one narrow linear cutting groove is provided on the surface of the concrete structure,
A continuous fiber reinforcement material of a flexible prepreg that is impregnated with resin but is in an uncured state is placed in the cutting groove, and the resin impregnated in the continuous fiber reinforcement material is cured, and then fixed in the cutting groove. Fixing the continuous fiber reinforcing material in the cutting groove by injecting an agent and curing the fixing agent;
A method for reinforcing a concrete structure is provided. Here, according to one embodiment, after the cutting groove is formed on the lower surface or the side surface of the concrete structure, after curing the impregnating resin of the continuous fiber reinforcing material installed in the cutting groove. Then, the opening of the cutting groove is covered with a lid member, the sticking agent is injected into the cutting groove from a sticking agent injection port provided in the lid member, and the sticking agent is hardened, whereby the continuous A fiber reinforcement is fixed in the cutting groove.

According to another aspect of the present invention, at least one narrow linear cutting groove is provided on the surface of the concrete structure,
Pre-applying a sticking agent in the cutting groove,
Before the fixing agent is cured, a continuous fiber reinforcing material of a flexible prepreg that is impregnated with a resin but is in an uncured state is pushed into a cutting groove to which the fixing agent is applied, and is installed. And fixing the continuous fiber reinforcement in the cutting groove by curing the adhesive.
A method for reinforcing a concrete structure is provided.

  In the present invention, according to one embodiment, the flexible continuous fiber reinforcing material includes a plurality of continuous fiber wires formed of a plurality of continuous reinforcing fibers, and is arranged in a slender shape in the longitudinal direction. The plurality of continuous fiber wires are fixed to each other with a wire fixing material, and formed into an elongated strip shape.

  According to another embodiment, the flexible continuous fiber reinforcing material has a plurality of continuous reinforcing fibers aligned in one direction, and the continuous reinforcing fibers are fixed to each other by a fixing material, and are formed into an elongated band shape. It is formed.

  According to another embodiment, the belt-like continuous fiber reinforcing material is reduced in the width direction by being shrunk, wound or folded in the width direction, and is inserted and installed in the cutting groove.

  According to another embodiment, the flexible continuous fiber reinforcing material is produced by knitting a continuous fiber wire formed of a large number of continuous reinforcing fibers into a rope shape or a string shape.

  According to another embodiment, the resin is a thermosetting resin such as a room temperature curing type or thermosetting type epoxy resin, vinyl ester resin, MMA resin, unsaturated polyester resin, acrylic resin, or phenol resin; Thermoplastic resins such as nylon, polyamide and PEEK; or thermoplastic epoxy resins.

  According to another embodiment, the fixing agent is a thermosetting resin such as an epoxy resin or an acrylic resin; a thermoplastic resin such as nylon, polyamide, or PEEK; or an organic material such as a thermoplastic epoxy resin, or It is an inorganic material such as cement mortar, expandable cement mortar, polymer cement mortar, or gypsum, or a mixed material obtained by mixing the organic material and the inorganic material.

  According to another embodiment, the reinforcing fiber is an inorganic fiber such as carbon fiber, glass fiber or basalt fiber; organic fiber such as aramid fiber, vinylon fiber or polyethylene fiber; or metal fiber such as steel fiber or stainless fiber. Or a hybrid fiber obtained by combining a plurality of these fibers.

  According to another embodiment, the Young's modulus of the continuous fiber reinforcement after resin impregnation and curing is 10 GPa to 600 GPa.

According to another embodiment, the concrete structure is a concrete slab,
The continuous fiber reinforcing material is installed in any one of the direction perpendicular to the floor slab support or the direction between floor slab supports, or in both the direction perpendicular to the floor slab support and the direction between the floor slab supports.

According to another embodiment, the tensile stiffness in one direction after the resin impregnation and hardening of the continuous fiber reinforcing material in the range to be reinforced is a tensile stiffness Sf per floor slab unit width represented by the following formula: 30 to 100 kN / mm It is said.
Sf = Af × Ef × nf
Af: Nominal cross-sectional area of continuous fiber reinforcement per one piece (mm ² )
Ef: Young's modulus (GPa) in the axial direction of the continuous fiber reinforcement
nf: Number of arrangement per unit width of continuous fiber reinforcement (lines / mm)

  According to another aspect of the present invention, there is provided a concrete structure that is reinforced by the method for reinforcing a concrete structure according to any one of the above.

According to still another aspect of the present invention, there is provided a continuous fiber reinforcing material used in the method for reinforcing a concrete structure according to any one of the above,
Flexibility characterized by having a large number of continuous reinforcing fibers and being in a dry state not impregnated with resin, or being impregnated with resin but uncured and having flexibility A continuous fiber reinforcement is provided.

  According to the present invention, the surface of the concrete structure can be visually recognized without covering most of the surface of the concrete structure, and the deterioration status of the concrete structure can be visually confirmed and water stagnating in the concrete structure can be prevented. . In addition, by using a continuous fiber reinforcing material having flexibility, it is possible to use a long reinforcing material having a length of 25 m or more, and if necessary, a length of 50 m or more, thus eliminating the need for a lap joint. However, there is no concern about the fatigue strength of the joint, and even when a joint is provided, the number of joints can be reduced by using a long continuous fiber reinforcement compared to the FRP rod. In addition, by using a continuous fiber reinforcing material having flexibility, the depth of the cutting groove formed in the concrete slab can be reduced, and a complicated structure is required. Even if the surface of the concrete is weakened, a sufficient effect can be obtained. Furthermore, by using a continuous fiber reinforcing material having flexibility in the present invention, workability and handleability are remarkably improved, and work time can be shortened.

FIG. 1A is a perspective view showing a schematic configuration of a concrete slab, and FIG. 1B is a cross-sectional view of a concrete slab reinforced by an embodiment of the reinforcing method of the present invention. 1 (c) is a cross-sectional view of a cutting groove portion to which a continuous fiber reinforcing material of a concrete floor slab is fixed. FIGS. 2A to 2C are plan views of the lower surface of the concrete slab for explaining an arrangement example of the continuous fiber reinforcing material in the reinforcing method of the present invention. 3A to 3D are schematic perspective views showing examples of concrete structures reinforced by the reinforcing method of the present invention. 4 (a), 4 (b), and 4 (c) are perspective views showing examples of continuous fiber reinforcing materials used in the reinforcing method of the present invention. FIGS. 5A, 5B, and 5C are perspective views showing examples of continuous fiber wires used in the reinforcing method of the present invention. 6 (a) and 6 (b) are perspective views showing an embodiment of a continuous fiber reinforcing material used in the reinforcing method of the present invention. FIG. 7 is a perspective view showing an embodiment of a continuous fiber reinforcing material used in the reinforcing method of the present invention. FIGS. 8A to 8H are process diagrams for explaining an embodiment of the reinforcing method of the present invention. Fig.9 (a) is sectional drawing which shows the Example of the cutting groove formed in the concrete structure for implementing the reinforcement method of this invention, FIG.9 (b), (c) is a strip | belt-shaped continuous fiber. It is a figure explaining the example which shrinks or revolves a reinforcing material in the width direction. FIGS. 10A to 10H are process diagrams for explaining an embodiment of the reinforcing method of the present invention. 11A to 11I are process diagrams for explaining an embodiment of the reinforcing method of the present invention. 12A to 12J are process diagrams for explaining an embodiment of the reinforcing method of the present invention. FIGS. 13A to 13H are process diagrams for explaining an embodiment of the reinforcing method of the present invention. FIG. 14 (a) is a diagram for explaining a crossing portion of a reinforcing material by a concrete structure reinforcing method using a conventional bar-shaped continuous fiber reinforcing material, and FIGS. 14 (b) and 14 (c) are possible according to the present invention. It is a figure explaining the crossing part of the reinforcing material by the concrete structure reinforcement method using a flexible continuous fiber reinforcing material. FIG. 15 is a cross-sectional view of a concrete structure for explaining another embodiment of the reinforcing method of the present invention.

  Hereinafter, the concrete structure reinforcing method, concrete structure and flexible continuous fiber reinforcing material according to the present invention will be described in more detail with reference to the drawings. In the reinforcing method of the concrete structure of the present embodiment described below, a floor slab of a road bridge will be described as an example of the concrete structure. However, the reinforcing method of the present invention is not limited to this. It can be widely applied to reinforced concrete structures such as columns.

  FIG. 1A shows a schematic configuration of a concrete slab 1 which is a concrete structure of the present embodiment. A pavement 2 is provided on the upper surface 1A of the concrete floor slab 1 on which the vehicle travels, and the lower surface 1B is supported on the pier 4 or the like by a main girder 3 installed in the traveling direction (bridge axis direction) of the vehicle or the like. FIGS. 1B and 1C are sectional views of the concrete slab 1 taken in the direction between the slab supports in the concrete slab 1, that is, in the direction orthogonal to the bridge axis direction in FIG. 2A, 2B, and 2C show examples of arrangement of the continuous fiber reinforcing material 10 when the concrete floor slab 1 is reinforced.

  The method for reinforcing a concrete floor slab 1 according to the present invention is provided with at least one cutting groove 30 having a narrow line shape on the lower surface 1B of the concrete floor slab, and in this embodiment, a plurality of cutting grooves 30 are provided. The continuous fiber reinforcing material 10 is installed on the floor slab, and the continuous fiber reinforcing material 10 is fixed in the cutting groove 30 with the fixing agent 40 and fixed to the floor slab 1 integrally.

  In the reinforcing method of the present invention, before the continuous fiber reinforcing material 10 is installed in the cutting groove 30, as described in FIGS. 4A to 4C, for example, for example, A flexible continuous fiber reinforcing material having an elongated strip shape having a width (W) and a length (L), and a plurality of continuous fiber wires 11 formed of a large number of continuous reinforcing fibers f, in the longitudinal direction. Each continuous fiber wire 11 is made into a strip-like continuous fiber reinforcing material 10 </ b> S fixed by a wire fixing material 12. In the present embodiment, the belt-like continuous fiber reinforcing material 10S is reduced in the width direction so as to conform to the shape of the cutting groove 30, that is, is shaped into a predetermined cross-sectional shape and inserted into the cutting groove 30 and installed. Is done. In this embodiment, the continuous fiber reinforcing material 10 that is the belt-like continuous fiber reinforcing material 10 </ b> S is fixed in the cutting groove 30 by the fixing agent 40. The fixing agent 40 can be an organic material such as resin, an inorganic material such as cement mortar, or a mixed material thereof.

  Further description will be made with reference to FIGS. 1A to 1C and FIGS. 2A to 2C. Concrete floor slab 1 is made of reinforced concrete (RC), as shown in FIG. 1B. Further, the main reinforcing bars 100 are buried in the floor slab concrete 1a and arranged in the direction between the floor slabs, and the distribution reinforcing bars 101 are arranged in a manner orthogonal to the main reinforcing bars 100, that is, in the bridge axis direction. Usually, the main reinforcing bars 100 are arranged with a predetermined cover depth H0 from the surface of the floor slab concrete 1a. Therefore, according to the method for reinforcing a concrete floor slab according to the present invention, the cutting groove 30 is formed on the lower surface 1B of the concrete floor slab 1 and at the cover depth H0 portion below the main reinforcing bar 100, A band-like continuous fiber reinforcing material 10S having a cross-sectional shape orthogonal to the longitudinal direction shaped into a predetermined shape so as to fit in the groove 30 is installed, that is, the continuous fiber reinforcing material 10 is installed. It is fixed. A more specific description of the reinforcing method will be described later.

  2 (a), 2 (b), and 2 (c) are views showing the lower surface 1B of the concrete floor slab 1 when the concrete floor slab 1 is viewed in the direction of arrow A from the lower side of FIG. 1 (b). According to the example concrete floor slab reinforcement method, the continuous fiber reinforcing material 10 is provided in the direction perpendicular to the floor slab support (FIG. 1 (b), FIG. 2 (a)) or the direction of the floor slab support (FIG. 2 (b)). It is installed in any one direction, or both directions of the direction perpendicular to the floor slab support and the direction between the floor slab supports (FIG. 2C). Therefore, as described above, the cutting groove 30 for embedding the continuous fiber reinforcing material 10 and fixing it with the fixing agent 40 is provided on the lower surface 1B of the concrete floor slab 1 and the desired continuous fiber reinforcing material 10 is disposed. Corresponding to the aspect, either the direction perpendicular to the floor slab supports (FIG. 1 (b), FIG. 2 (a)) or the direction between floor slab supports (FIG. 2 (b)), or the direction perpendicular to the floor slab supports and It is formed in both directions (FIG. 2 (c)) in the direction between the floor slab supports.

  As described above, the method for reinforcing a concrete structure according to the present invention is not limited to the reinforcement of a floor slab of a road bridge described in the above embodiment, but also for reinforcing a reinforced concrete structure such as a beam or a column. Can be applied.

  That is, FIGS. 3A to 3C show examples in which the present invention is applied to the concrete pillar 1. In this case, the cutting groove 30 is formed on the outer surface of the concrete column 1 in the axial direction of the column (FIG. 3A), in the direction orthogonal to the axial direction of the column (FIG. 3B), or spirally ( 3 (c)) or a combination of these (not shown), the continuous fiber reinforcing material 10 is embedded in the groove 30 and fixed with the fixing agent 40. FIG. 3D shows an example in which the present invention is applied to the concrete beam 1. In this case, a cutting groove 30 is formed in, for example, the upper, lower surface 1A, 1B, or side surfaces 1C, 1D of the concrete beam 1, and the continuous fiber reinforcing material 10 is embedded in the groove, so Fixed.

  Next, with reference to FIG. 4 (a)-(c), FIG. 5 (a)-(c), FIG. 6 (a), (b), the continuous fiber used when implementing the reinforcement method of this invention The reinforcing material 10 will be further described.

(Continuous fiber reinforcement)
・ Specific example 1
According to an example, the continuous fiber reinforcing material 10 is formed into an elongated strip shape before being inserted and installed in the cutting groove 30 as shown in FIGS. The continuous fiber reinforcing material 10S. The belt-like continuous fiber reinforcing material 10S has a plurality of continuous fiber wires 11 formed by a large number of continuous reinforcing fibers f, arranged in a slender shape in the longitudinal direction. It is fixed in one piece, and is formed in an elongated band shape having a width W and a length L. The belt-like continuous fiber reinforcing material 10S has flexibility, and can be transported by being rolled or folded, and there are no restrictions on transportation, so the width W of the belt-like continuous fiber reinforcing material 10S. And length L can be manufactured to arbitrary dimensions, and is cut | disconnected suitably in use. Usually, from the viewpoint of handling, the width W is 50 to 1000 m and the length L is 10 to 100 m.

  Next, the band-like continuous fiber reinforcing material 10S will be described in more detail.

  According to an example of the belt-like continuous fiber reinforcing material 10S, the continuous fiber wire 11 has a plurality of continuous reinforcing fibers (monofilaments) f aligned in one direction as shown in FIG. Accordingly, a continuous fiber bundle 11A having a resin-unimpregnated flexibility that is loosely twisted and converged according to the above is obtained. For example, taking a case where carbon fibers are used as reinforcing fibers, for example, single fibers (carbon fiber monofilaments) f having an average diameter of 7 μm are converged, for example, 1000 to 100,000, generally 3000 to 60000. A continuous fiber bundle 11A having flexibility without resin impregnation can be used.

  As shown in FIG. 4 (a), a plurality of continuous fiber bundles 11A are arranged in a slender shape in the longitudinal direction, that is, are arranged apart from each other by a gap g, and the continuous fiber bundles 11A are fixed to each other with a wire. By fixing with the material 12, an integrated flexible strip-shaped continuous fiber reinforcing material 10 </ b> S is produced. At this time, the gap g between the continuous fiber bundles 11A and 11A is not limited, but is 0.1 to 50 mm, and is usually 0.5 to 5 mm from the viewpoint of manufacturing and handling. The

  As a method of fixing each continuous fiber bundle 11A with the wire fixing material 12, for example, as shown in FIG. 4 (a), a plurality of yarns arranged in a single direction using wefts as the wire fixing material 12 are used. A method of driving and knitting a wire rod, that is, a continuous fiber bundle 11A orthogonal to the constant interval (Pc) may be employed. The interweaving interval (Pc) of the weft is not particularly limited, but is usually selected in the range of an interval of 10 to 200 mm in consideration of the handleability of the produced belt-like continuous fiber reinforcing material 10S.

  At this time, the weft 12 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 for fixing each continuous fiber bundle 11A in a slender shape, as shown in FIG. 4 (b), as the wire fixing material 12, for example, a flexible member such as an adhesive tape or an adhesive tape is used. can do. The flexible member 12 includes a plurality of continuous fiber wires 11 arranged in a slender shape, i.e., one side surface of the wire at a constant interval (Pc) orthogonal to the continuous fiber bundle 11A in this example, Or fix it on both sides. As the flexible member 12, an adhesive tape such as a vinyl chloride tape, a paper tape, a cloth tape, a non-woven tape or an adhesive tape having a width (w1) of about 1 to 30 mm is used.

  Furthermore, as another method for fixing each continuous fiber bundle 11A in a slender shape, as shown in FIG. 4 (c), a mesh-like support sheet can be used as the wire fixing material 12. A plurality of wire rods in which the surfaces of the warp yarns 12a and the weft yarns 12b constituting the mesh-like support sheet 12 are impregnated with a low-melting-point type thermoplastic resin in advance, and the mesh-like support sheet 12 is arranged in a sled shape, that is, The continuous fiber bundle 11A is laminated on one or both sides and heated and pressed to weld the warp 12a and weft 12b portions of the mesh support sheet 12 to the continuous fiber bundle 11A.

  In addition to the biaxial configuration, the mesh-like support sheet 12 is formed by orienting glass fibers in three axes, or only the weft yarns 12b orthogonal to the carbon fibers arranged in one direction. It can also be adhered to the so-called continuous fiber bundle 11A formed so as to be oriented in one axis and arranged in the above-mentioned manner.

  As the yarn of the wire fixing material 12, for example, a double-structured composite fiber having a glass fiber in the core and a low melting point heat-fusible polyester arranged around it is also preferably used. .

  In the above description, as shown in FIG. 5 (a), the continuous fiber wire 11 is formed by aligning a large number of continuous reinforcing fibers (monofilaments) f in one direction or by loosely twisting as necessary. Although it has been described that it is a continuous fiber bundle 11A that has converged and is not impregnated with flexibility, as shown in FIG. 5B, the continuous fiber bundle 11A is further covered with a covering yarn along the longitudinal direction. It can also be set as the continuous fiber bundle 11Am bundled by the strips 13.

  As the covering yarn 13, two yarns made of 50 denier polyester fiber are used, and a continuous fiber bundle 11A is formed by a method in which the covering yarns 13a and 13b are moved up and down by braided knitting, S winding and Z winding. Can be wrapped around the outside. The covering pitch Pc can be set to, for example, 25 to 33 windings per 10 cm in the longitudinal direction of the continuous fiber bundle 11A (Pc = 3 to 4 mm in FIG. 5B). Moreover, in order to obtain favorable linearity without generating bending along the longitudinal direction of the continuous fiber bundle 11A, the covering yarn 13 is given a tension in the range of 50 to 80 g / string, That is, it is preferable to cover the continuous fiber bundle 11A with a tension of 200 g / piece.

  Using the continuous fiber bundle 11Am bundled with the covering yarn 13, the continuous fiber bundle 11Am is integrated with the fixing material 12 in the same manner as described with reference to FIGS. Thus, the so-called dry belt-like continuous fiber reinforcing material 10S can be produced.

・ Specific example 2
In the above specific example 1, the continuous fiber wire 11 constituting the strip-shaped continuous fiber reinforcing material 10S has a large number of continuous reinforcing fibers (monofilaments) f aligned in one direction or loosely twisted as necessary. It was set as the dry continuous fiber bundles 11A and 11Am which were converged and had the resin non-impregnation flexibility.

  In this second specific example, the continuous fiber bundles 11A and 11Am used in the first specific example 1 are used as the continuous fiber wire 11 constituting the strip-shaped continuous fiber reinforcing material 10S. However, as shown in FIG. A so-called prepreg continuous fiber prepreg 11 </ b> B having the flexibility that the continuous fiber bundles 11 </ b> A and 11 </ b> Am are impregnated with the resin R to be in an uncured state, that is, a semi-cured state, is used as the continuous fiber wire 11. Using this continuous fiber prepreg 11B, the strip-like continuous fiber reinforcing material 10S of the prepreg can be produced in the same manner as described with reference to FIGS.

  As another method, a continuous belt-like continuous fiber reinforcing material 10S can be produced by producing a dry continuous-band continuous fiber reinforcing material 10S and impregnating each continuous fiber bundle 11A, 11Am of the continuous belt-like fiber reinforcing material 10S with resin. .

・ Specific example 3
In the specific examples 1 and 2, a continuous fiber bundle having flexibility, in which a large number of continuous reinforcing fibers (monofilaments) f are aligned in one direction, or are loosely twisted as necessary to converge. Using 11A and 11Am, a dry or prepreg belt-like continuous fiber reinforcing material 10S was produced.

  In this specific example 3, as shown in FIGS. 6 (a) and 6 (b), a non-resin-impregnated fiber sheet 14 that is formed in a sheet shape by aligning continuous reinforcing fibers f in one direction is used. The non-resin-impregnated (dry) or resin-impregnated resin-uncured, ie, semi-cured (prepreg), strip-shaped continuous fiber reinforcing material 10S is produced.

That is, the fiber sheet 14 is the same as that described with reference to FIG. 4 (c) in connection with the specific example 1 described above. It can be set as the structure hold | maintained by the wire fixing material 15 used as a shaped support sheet | seat. For example, when carbon fibers are used as the reinforcing fibers f, for example, a plurality of unimpregnated single fiber bundles in which 6000 to 24000 single fibers (carbon fiber monofilaments) f having an average diameter of 7 μm are converged in parallel in one direction. Used to align. The fiber basis weight of the carbon fiber sheet 14 is usually 30 to 1000 g / m ² .

  Carbon in which the surface of warp yarns 15a and weft yarns 15b constituting the mesh-like support sheet 15 as the wire fixing material 15 is impregnated in advance with a low melting point type thermoplastic resin, and the mesh-like support sheet 15 is arranged in a sheet shape. The fibers are laminated on one side or both sides and heated and pressed to weld the warp yarns 15a and the weft yarns 15b of the mesh-like support sheet 15 to the carbon fiber sheet.

  In addition to the biaxial configuration, the mesh-like support sheet 15 is formed by orienting glass fibers in three axes, or only the weft yarns 15b orthogonal to the carbon fibers arranged in one direction. It can also be bonded to the so-called uniaxially oriented carbon fibers that are arranged and aligned in the form of a sheet.

  As the yarn of the wire fixing material 15, 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. .

  As another method, as shown in FIG. 6B, the belt-like continuous fiber reinforcing material 10S includes a unidirectional reinforcing fiber sheet 14 in which reinforcing fibers f are arranged in one direction, and is orthogonal to the axial direction of the reinforcing fibers f. It is also possible to fabricate the weft 16 by weaving (or weaving).

  The continuous continuous fiber reinforcing material 10S using the unidirectional reinforcing fiber sheet 14 of the specific example 3 can use a so-called dry continuous continuous fiber reinforcing material 10S that is not impregnated with resin as the continuous fiber wire 11. On the other hand, the unidirectional reinforcing fiber sheet 14 is impregnated with the resin R, and the resin R is left in an uncured state, that is, still in a semi-cured state. Therefore, the so-called prepreg strip-shaped continuous fiber having flexibility. The reinforcing material 10 </ b> S can be used as the continuous fiber wire 11.

・ Specific example 4
In the above specific examples 1 to 3, the continuous fiber reinforcing material 10 used in the present invention is a flexible continuous fiber reinforcing material 10S that is formed into an elongated belt shape, but the continuous fiber reinforcing material used in the present invention is used. The material 10 is not limited to this.

  The continuous fiber reinforcing material 10 that can be used in the present invention is, for example, a rope member 10R of various forms such as a twisted structure as shown in FIG. 7, a knitted structure or a Kahn mantle structure, or not shown. However, it is possible to use various rope-like members or string-like members such as braid members and bag knitting members.

  Of course, each of the rope-like members 10R or the string-like members can be used as a dry continuous fiber reinforcing material 10 that is not impregnated with resin, and is impregnated with resin R, and the resin R is still in a semi-cured state. It can be used as the continuous fiber wire 10 in a so-called prepreg state, which is left flexible.

  The reinforcing fibers f of the continuous fiber reinforcing material 10 described in the specific examples 1 to 4 are inorganic fibers such as carbon fibers, glass fibers, and basalt fibers; organic fibers such as aramid fibers, vinylon fibers, and polyethylene fibers; or steel. One fiber of metal fibers such as fibers and stainless steel fibers, or a hybrid fiber combining a plurality of these fibers can be used.

  The FRP material formed by the continuous fiber reinforcing material 10 used in the present invention is preferably a high-strength CFRP using carbon fiber as the reinforcing fiber f, but is not limited thereto, and is a high-elasticity CFRP. Alternatively, AFRP using an aramid fiber as the reinforcing fiber f, GFRP using a glass fiber, BFRP using a basalt fiber, or the like can be used, and the Young's modulus is preferably 10 GPa to 600 GPa.

  The matrix resin R impregnated in the prepreg continuous fiber reinforcing material 10 described in the above specific examples includes a thermosetting resin such as an epoxy resin and an acrylic resin; a thermoplastic resin such as nylon, polyamide, and PEEK; Alternatively, a thermoplastic epoxy resin or the like can be used. The resin content is 20 to 75% by weight, and preferably 40 to 60% by weight.

(Reinforcing method)
As understood from the above description, according to the method for reinforcing a concrete structure of the present invention, a large number of lines installed in the narrow linear cutting grooves 30 formed on the surface of the concrete structure 1 are provided. A flexible continuous fiber reinforcing material 10 having continuous reinforcing fibers f and uncured resin R cures the resin R in the cutting groove 30. At the same time, the continuous fiber reinforcing material 10 that is an FRP material hardened in the cutting groove 30 is fixed in the cutting groove 30 by the fixing agent 40, whereby the continuous fiber reinforcing material 10 that is the FRP material is a concrete structure. Reinforced concrete structure is achieved by being integrally fixed to the object.

  Next, the concrete structure reinforcing method according to the present invention will be described more specifically with reference to examples.

Example 1
As an example of the reinforcing method of the present invention, a concrete floor in the case where the continuous fiber reinforcing material 10S having the continuous fiber bundle 11A (or the continuous fiber bundle 11Am) as the continuous fiber wire 11 described in the specific example 1 is used. A method for reinforcing the plate will be described.

  According to the present embodiment, the resin R is impregnated with the resin-unimpregnated flexible continuous fiber wire 11 which is the continuous fiber wire 11 of the strip-shaped continuous fiber reinforcing material 10S, and the resin R is in an uncured state. As shown in FIG. 9 (b), the belt-like continuous fiber reinforcing material 10S is reduced in the width direction and pushed into the cutting groove 30 to be installed. Next, the impregnating resin R of the continuous fiber reinforcing material 10 installed in the groove 30 is cured. At this time, the impregnating resin R acts as a fixing agent 40, and by hardening the resin R, the continuous fiber reinforcing material 10 made of FRP (fiber reinforced plastic) material is fixed in the cutting groove 30 and the floor slab 1. It is fixed to the unit.

  Furthermore, if it demonstrates in detail with reference to Fig.8 (a)-(h) to Fig.10 (a)-(h), according to the reinforcement method of the concrete floor slab of a present Example, it shows to Fig.8 (a). Thus, first, the cutting groove 30 is formed on the lower surface 1B of the concrete floor slab 1 in any one of the modes described in FIGS. 2A, 2B, and 2C as desired. The cutting grooves 30 are formed at a predetermined pitch P using a diamond cutter or a water jet. The pitch P is set to a predetermined value in the range of 50 to 500 mm, usually 100 to 300 mm. Moreover, as shown in (a-1) to (a-4) of FIG. 9A, the cross-sectional shape of the cutting groove 30 is arbitrary such as a square shape or a rectangular shape, a semicircular shape, a semielliptical shape, or the like. It can be a shape. However, in FIG. 8A, since the cover depth H0 of the floor slab 1 is generally about 20 to 50 mm, the cutting groove 30 usually has a width (W1) and a depth (H1). , 5 to 50 mm, respectively. For example, for example, the cutting groove 30 may be a square having a width (W1) and a depth (H1) of 15 mm each, and the pitch P may be 125 mm. In this case, as described above, the continuous fiber reinforcing material 10 can be configured, for example, as a belt-like continuous fiber reinforcing material 10S shown in FIG. 4A, and when carbon fibers are used as the reinforcing fibers, the average diameter is increased. A continuous fiber bundle 11A in which 24000 single fibers (carbon fiber monofilaments) of 7 μm are converged, or 72 continuous fiber bundles 11Am having covering yarns are arranged 5 mm apart from each other and used in a sled shape. can do.

  Next, in FIG. 8B, a primer Pm, for example, an epoxy resin primer is applied in the groove 30 cut in the process of FIG. However, the primer Pm is not necessarily required.

  The so-called dry strip-like continuous fiber reinforcing material 10S, which is not impregnated with the resin shown in FIG. After the impregnation, as shown in FIGS. 9B and 9C, for example, the tip portion (the left end portion in FIG. 9B) is sequentially reduced in the width direction, that is, for example, in the width direction. To fit in the cutting groove 30 by being folded down (FIG. 9B), rolled up (FIG. 9C), or folded while being folded along the longitudinal direction. Shaped into a unique shape. As described above, the resin impregnation can be performed by, for example, immersing the continuous fiber reinforcing material in a container filled with the resin and defoaming with a roller. A method may be employed. The resin content in the continuous fiber reinforcing material 10 is 20 to 75% by weight, preferably 40 to 60% by weight.

  The continuous fiber reinforcing material 10 shaped into a predetermined shape and impregnated with resin is inserted and installed in the cutting groove 30 sequentially from the tip in an uncured state of the resin (FIGS. 8C and 8D). )). At this time, the continuous fiber reinforcing material 10 is pressed in from the outside of the cutting groove 30, thereby closely contacting the cutting groove 30 and following the cross-sectional shape of the cutting groove 30, that is, in a state adapted to the cross-sectional shape. Are installed and installed. Resin R impregnated in the continuous fiber reinforcing material 10, that is, the matrix resin may be a room temperature curing type or thermosetting type epoxy resin, vinyl ester resin, MMA resin, unsaturated polyester resin, acrylic resin, or phenol resin. Thermosetting resins such as nylon, polyamide, PEEK and other thermoplastic resins; or thermoplastic epoxy resins and the like can be used. Preferably, a room-temperature curable liquid resin is used and placed in the cutting groove 30 and then cured at room temperature, or a thermosetting liquid resin is used and placed in the cutting groove 30 and then heated. It is also possible to cure. Thereby, the impregnated resin of the continuous fiber reinforcing material 10 is cured, and the continuous fiber reinforcing material 10 is fixed in the cutting groove 30. In this embodiment, the resin R impregnated in the continuous fiber reinforcing material 10, that is, the matrix resin acts as the fixing agent 40.

  If necessary, as shown in FIG. 8E, the adhering agent 40 can be applied to the continuous fiber reinforcing material 10 from the outside of the groove 30 to fill the gap. Then, as shown in FIG.8 (f), a trowel finish is performed so that the surface of the fixing agent 40 may become substantially the same plane as the concrete surface 1B. As the fixing agent 40, as described above, an organic material such as a resin, an inorganic material such as cement mortar, or a mixed material thereof can be used. However, the resin R impregnated in the continuous fiber reinforcing material 10 and The same resin can be used. However, it is preferable to use a putty-like resin having a large viscosity.

  Next, as shown in FIG. 8G, after the fixing agent 40 is cured, a protective coating 41 can be applied to the surface of the fixing agent in order to improve the weather resistance. As the protective coating 41, for example, an acrylic paint can be applied.

  Further, as shown in FIG. 8 (h), before the reinforcement with the continuous fiber reinforcing material 10 (that is, the process of FIG. 8 (a) above) for the purpose of suppressing deterioration of the concrete due to ASR or frost damage as required. Before or after reinforcement (that is, after performing the step of FIG. 8G), as a surface treatment method for concrete, water repellent (for example, silane-based water repellent) is applied or impregnated. Concrete surface protection work 42 such as injection of an agent (for example, lithium nitrite) can be performed.

Example 2
A second embodiment of the present invention will be described with reference to FIGS. In the present embodiment, the reinforcing method shown in FIGS. 8A to 8H is the process shown in FIGS. 10C and 10D, which is a process corresponding to FIGS. 8C and 8D. Differently, the other steps are the same.

  That is, in Example 1 described above, the continuous fiber reinforcing material 10 that has been impregnated with the resin and is shaped into a predetermined shape is pushed into the cutting groove 30 and installed (FIG. 8C). (D)). On the other hand, in the second embodiment, as shown in FIG. 10C, the cutting groove 30 is filled with the fixing agent 40 in advance.

  The filling method of the fixing agent 40 into the groove 30 includes a method of applying the fixing agent 40 with a trowel, a method of filling from a nozzle of a cartridge gun equipped with a static mixer nozzle, and a stirring agent 40 fed from a pump and filled from a hose. There are ways to do it.

  As shown in FIGS. 9B and 9C, the belt-like continuous fiber reinforcing material 10S used in the present embodiment is reduced in the width direction sequentially from the tip portion, for example, as shown in FIGS. That is, for example, by shrinking in the width direction, entraining, or folding, it is shaped into a shape that fits into the cutting groove 30 and impregnated with the resin R.

  Next, the resin-impregnated and uncured continuous fiber reinforcing material 10 shaped into a predetermined shape is inserted and installed in the cutting groove 30 filled with the fixing agent 40 before the fixing agent 40 is cured. (FIGS. 10C and 10D). At this time, the continuous fiber reinforcing material 10 is inserted from the outside so as to closely follow the cross-sectional shape of the cutting groove 30 in the cutting groove 30, that is, in a state adapted to the cross-sectional shape, Installed. Next, the fixing agent 40 in the cutting groove 30 is cured to fix the continuous fiber reinforcing material 10 in the groove 30. In addition, the continuous fiber reinforcing material 10 can also be hardened by heating from the surface.

  In the present embodiment, the above-described materials can be used as the fixing agent 40, but the same resin R as the matrix resin of the continuous fiber reinforcing material 10 is preferably used. However, as the resin, a resin having a viscosity that does not sag after coating is preferably used. As the resin viscosity, for example, the viscosity can be in the range of 50000 to 5000000 mPa · sec at 23 ° C., and the thixotropic index can be in the range of 4 to 7.

  Then, the process shown to FIG.10 (e)-(h) which is the same process as the process shown to FIG.8 (e)-(h) of Example 1 can be implemented.

Example 3
A third embodiment of the present invention will be described with reference to FIGS. In this embodiment, the reinforcing method of the first embodiment shown in FIGS. 8A to 8H is a process corresponding to FIGS. 8C and 8D. FIGS. , (E), the other steps are the same.

  That is, in Example 1 described above, the uncured continuous fiber reinforcing material 10 shaped into a predetermined shape and impregnated with resin was placed in the cutting groove 30 and installed (FIG. 8 (c). ), (D)). On the other hand, in this Example 3, as shown in FIG.11 (c), it has the continuous fiber bundle 11A or the continuous fiber bundle 11Am, and the shape | molded dry continuous fiber reinforcing material 10 which is not impregnated with resin is used. Is inserted into the cutting groove 30 and installed. Thereafter, the impregnating resin R is injected into the groove 30 and the continuous fiber reinforcing material 10 is impregnated with the resin R, and at the same time, the continuous fiber reinforcing material 10 impregnated with the resin is bonded into the groove. In this embodiment, the point that the impregnating resin R to the continuous fiber reinforcing material 10 also functions as the fixing agent 40 is the same.

  In this example, as shown in FIG. 11C, when the construction surface is the lower surface 1B, the continuous fiber reinforcing material 10 is placed in the cutting groove 30 as shown in FIG. After inserting and installing, the opening of the cutting groove is covered with the lid member 20 and closed. The lid member 20 is an elongated belt-like member that covers an opening that is opened along the longitudinal direction of the cutting groove 30, for example, an elongated plate member made of resin or metal. In order to prevent the resin R from flowing out between the opening of the cutting groove 30 and the lid member 20, the lid member 20 seals the contact area with the structure surface 1 </ b> B with the seal member 21. Next, as shown in FIG. 11 (e), the impregnating resin R is injected into the groove 30 through an injection port 22 appropriately opened in the lid member 20. Thereby, as described above, the continuous fiber reinforcing material 10 disposed in the cutting groove 30 is impregnated with the resin R, and at the same time, the continuous fiber reinforcing material 10 impregnated with the resin is bonded into the groove 30.

  Then, after resin R hardens | cures, the sealing member 21 and the cover member 20 can also be removed from the cutting groove 30 area | region. After removing the sealing member 21 and the lid member 20, the steps shown in FIGS. 11 (f) to (i), which are the same steps as the steps shown in FIGS. 8 (e) to (h) in the first embodiment, are performed. be able to.

  In the above description of the third embodiment, the case where the construction surface is the lower surface 1B of the structure has been described. However, even when the construction surface is the side surface of the structure, the structure can be reinforced in the same process. it can.

  In addition, when the construction surface is the upper surface of the structure, although not shown in the figure, as will be apparent to those skilled in the art, since the opening of the cutting groove 30 is opened upward, When the disposed continuous fiber reinforcing material 10 is impregnated with the resin R, the resin R does not flow out of the cutting groove opening. Accordingly, in this case, the resin R can be injected without closing the opening of the cutting groove 30 in which the continuous fiber reinforcing material 10 is disposed with the lid member 20.

Example 4
A fourth embodiment of the present invention will be described. In Examples 1 to 3, a so-called dry continuous fiber reinforcing material 10 that is not impregnated with resin is used, and the dry continuous fiber reinforcing material 10 is impregnated with resin and then pushed into a cutting groove and placed. Alternatively, after the continuous continuous fiber reinforcing material 10 is disposed in the cutting groove, the continuous fiber reinforcing material 10 is impregnated with resin. In the present Example 4, as the continuous fiber reinforcing material 10, the so-called prepreg continuous having, for example, the continuous fiber prepreg 11 </ b> B that is impregnated with the resin and is still semi-cured as described with reference to the specific examples 1 to 4 above. A fiber reinforcement 10 is used.

  The fourth embodiment will be described with reference to FIGS. According to the present embodiment, as described in the first embodiment, as shown in FIG. 12 (a), the cutting groove 30 is formed on the lower surface 1B of the concrete floor slab 1, and then, FIG. 12 (b). As shown in FIG. 12, a primer Pm, for example, an epoxy resin primer is applied in the groove 30 cut in FIG. However, the primer Pm is not necessarily required. Next, as shown in FIGS. 12C and 12D, the prepreg continuous fiber reinforcing material 10 is formed, for example, as shown in FIGS. 9B and 9C. (B) is sequentially reduced in the width direction, that is, for example, contracted in the width direction (FIG. 9B), rolled in (FIG. 9C), or illustrated. However, it is shaped into a shape that fits into the cutting groove 30 by folding it while being folded back along the longitudinal direction, and is pushed into the cutting groove 30 and placed. In this embodiment, the prepreg continuous fiber reinforcing material 10 disposed in the cutting groove 30 is subsequently cured by heating or ultraviolet irradiation as shown in FIG. Alternatively, it can be cured by applying a curing agent to the prepreg continuous fiber reinforcing material 10. The curing agent is appropriately selected according to the impregnating resin R of the prepreg continuous fiber reinforcing material 10.

  Next, in this embodiment, as shown in FIGS. 12 (e) and 12 (f), in the cutting groove 30 in which the continuous fiber reinforcing material 10 cured in the process of FIG. The agent 40 is injected, and the continuous fiber reinforcing material 10 is bonded in the groove. In this embodiment, after the prepreg continuous fiber reinforcing material 10 is cured in this way, the fixing agent 40 is injected into the cutting groove 30. The reason is that after the injection of the fixing agent 40, the prepreg continuous fiber is injected. This is because the resin of the reinforcing material 10 cannot be cured or becomes difficult.

  In this embodiment, as shown in FIG. 12D, when the construction surface is the lower surface 1B, the opening of the cutting groove 30 is covered with the lid member 20 as shown in FIG. Cover and close. The lid member 20 is an elongated belt-like member that covers an opening that is opened along the longitudinal direction of the cutting groove 30, for example, an elongated plate member made of resin or metal. In order to prevent the fixing agent 40 from flowing out between the opening of the cutting groove 30 and the lid member 20, the contact area between the lid member 20 and the structure surface 1 </ b> B is sealed with the seal member 21. Next, the fixing agent 40 is injected into the groove 30 through the inlet 22 that is appropriately opened. Thereby, as described above, the continuous fiber reinforcing material 10 disposed in the cutting groove 30 is fixed in the groove 30. In the present embodiment, the fixing agent 40 can use the same resin R as the matrix resin of the continuous fiber reinforcing material 10.

  Thereafter, after the fixing agent 40 is cured, the seal member 21 and the lid member 20 can be removed from the cutting groove 30 region. After the sealing member 21 and the lid member 20 are removed, the steps shown in FIGS. 12G to 12J, which are the same steps as those shown in FIGS. 8E to 8H in the first embodiment, are performed. be able to.

  That is, as shown in FIG. 12G, the fixing agent 40 is applied again to the continuous fiber reinforcing material 10 from the outside of the groove 30 to fill the gap. Then, as shown in FIG.12 (h), a trowel finish is performed so that the surface of the fixing agent 40 may become substantially flush with the concrete surface 1B.

  Next, as shown in FIG. 12 (i), after the fixing agent 40 is cured, a protective coating 41 can be applied to the surface 1B of the fixing agent in order to improve the weather resistance. As the protective coating 41, for example, an acrylic paint can be applied.

  If necessary, as shown in FIG. 12 (j), for the purpose of suppressing deterioration of concrete due to ASR or frost damage, before reinforcement with the continuous fiber reinforcing material 10 (that is, FIG. 12 (a) above). Before or after the step (or after the step shown in FIG. 12 (i)), as a concrete surface treatment method, water repellent (for example, silane water repellent) is applied. Concrete surface protection work 42 such as press-fitting of an impregnating agent (for example, lithium nitrite) can be performed.

  In the above description of the fourth embodiment, the case where the construction surface is the lower surface 1B of the structure has been described. However, even when the construction surface is the side surface of the structure, the structure can be reinforced in the same process. it can.

  In addition, when the construction surface is the upper surface of the structure, although not shown in the figure, as will be apparent to those skilled in the art, since the opening of the cutting groove 30 is opened upward, When the continuous fiber reinforcing material 10 disposed is impregnated with the fixing agent 40, the fixing agent 40 does not flow out of the cutting groove opening. Accordingly, in this case, the fixing agent 40 can be injected without closing the opening of the cutting groove 30 in which the continuous fiber reinforcing material 10 is disposed with the lid member 20.

Example 5
A fifth embodiment of the present invention will be described with reference to FIGS. Also in the present embodiment, as in the fourth embodiment, as shown in FIGS. 13A and 13B, the cutting groove 30 is formed, and the primer Pm is applied as necessary.

  Here, in Example 4 described above, the continuous fiber reinforcing material 10 of the prepreg shaped into a predetermined shape is inserted into the cutting groove 30 and set and cured, and then the adhesive 40 is put into the cutting groove 30. Was to be injected. On the other hand, in Example 4, as shown in FIG. 13C, the cutting groove 30 is filled with the fixing agent 40 in advance.

  The filling method of the fixing agent 40 into the groove 30 includes a method of applying the fixing agent 40 with a trowel, a method of filling from a nozzle of a cartridge gun equipped with a static mixer nozzle, and a stirring agent 40 fed from a pump and filled from a hose. There are ways to do it.

  Next, the prepreg continuous fiber reinforcing material 10 shaped into a predetermined shape is inserted and installed in the cutting groove 30 filled with the fixing agent 40 before the fixing agent 40 is cured (see FIG. 13 (c), (d)). At this time, the continuous fiber reinforcing material 10 is inserted from the outside so as to closely follow the cross-sectional shape of the cutting groove 30 in the cutting groove 30, that is, in a state adapted to the cross-sectional shape, Installed. Next, by heating from the surface, the prepreg continuous fiber reinforcing material 10 is cured, and the fixing agent 40 in the cutting groove 30 fixes the continuous fiber reinforcing material 10 in the groove 30.

  Thereafter, the steps shown in FIGS. 13E to 13H, which are the same steps as those shown in FIGS. 12G to 12J in the fourth embodiment, are performed.

  As mentioned above, according to the concrete floor slab reinforcement method demonstrated with reference to Examples 1-5, although demonstrated as what the one continuous fiber reinforcement material 10 is arrange | positioned in the cutting groove 30, a plurality of continuous It is also possible to arrange the fiber reinforcement 10.

In addition, the tensile stiffness Sf in one direction of the continuous fiber reinforcing material 10 within the range to be reinforced by the reinforcing method of the present invention is such that the tensile stiffness Sf per floor slab unit width represented by the following formula is 30 to 100 kN / mm.
Sf = Af × Ef × nf
Af: Nominal cross-sectional area of continuous fiber reinforcement per one piece (mm ² )
Ef: Young's modulus (GPa) in the axial direction of the continuous fiber reinforcement
nf: Number of arrangement per unit width of continuous fiber reinforcement (lines / mm)

  Moreover, in the said Examples 1-5, as shown to FIG. 2 (a), (b), the continuous fiber reinforcement 10 is in the direction perpendicular to the floor slab support which is a concrete structure, or in the direction between floor slabs. Although the embodiment arrange | positioned along was demonstrated, as shown in FIG.2 (c), the continuous fiber reinforcement 10 can also be arrange | positioned along both the perpendicular direction between floor slab branches, and the direction between floor slabs. Of course, a concrete structure other than a concrete slab, for example, a concrete column or beam shown in FIG. 3 is also continuous in the longitudinal direction of the column or beam and in the direction orthogonal to the longitudinal direction of the column or beam. A fiber reinforcement 10 can be placed. In the case of a concrete column, as shown in FIG. 3C, the cutting groove 30 can be formed in a spiral shape, and the continuous fiber reinforcing material 10 can be installed in the groove 30 as described above.

  For example, FIG. 14A shows a comparative example using a conventional rod-like continuous fiber reinforcing material 10PR (10PRA, 10PRB). As shown in FIG. As shown in FIG. 14 (a), the grooves 30 (30A, 30B) are cut within the range of the cover depth H0, for example, the cutting groove 30A cut in the direction perpendicular to the floor slab support and the direction between the floor slab supports. The cutting groove 30B to be cut is made different in the height direction. Here, the rod-like continuous fiber reinforcement 10PRA is arranged in the cutting groove 30A cut in the direction perpendicular to the floor slab support, and then the rod-like continuous fiber reinforcement 10PRB is arranged in the cutting groove 30B cut in the direction of the floor slab support. Shall. Therefore, in order to arrange the rod-like continuous fiber reinforcements 10PRA and 10PRB, for example, the depth H1A of the groove 30A in the direction perpendicular to the floor slab support is set to the cover depth H0 (H1A≈H0) from the floor plate lower surface 1B side. On the other hand, the groove 30B in the direction between the floor slabs needs to be cut at a depth H1B that is half the cover depth H0 (H1B≈H0 × 1/2).

  On the other hand, according to one embodiment of the present invention shown in FIGS. 14 (b) and 14 (c), in the same manner as in the prior art, for example, it is cut in a direction perpendicular to the floor slab support within the range of the cover depth H0. Even if the cutting groove 30A and the cutting groove 30B cut in the direction between the floor slabs are shifted in the height direction, the continuous fiber materials 10A and 10B installed in the cutting grooves 30A and 30B are flexible. It can be compressed and deformed even after being installed in the groove 30. Accordingly, in the intersecting portion 10IS of the continuous fiber materials 10A and 10B shown in FIGS. 14B and 14C, at least the groove width of the intersecting portion 10IS region is slightly widened, so that the continuous fiber materials 10A and 10B have a slightly wider width. By compressing the intersection, the thickness can be reduced. Therefore, even if the depth H2B of the groove 30B in the direction of the floor slab span is cut at a depth half of the cover depth H0 (H2B≈H0 × 1/2), the groove 30A in the direction perpendicular to the floor slab span is: The depth H2A can be cut from the floor plate lower surface 1B side substantially below the cover depth H0, that is, H2A <H1A, and the groove depth can be reduced to improve work efficiency. Can be made.

  Furthermore, according to the present invention, the continuous fiber reinforcing material 10 formed of the continuous fiber wire 11 such as the flexible continuous fiber bundle 11A and the continuous fiber prepreg 11B has flexibility. Therefore, as shown in FIG. 15, when the unevenness of the floor slab lower surface 1 </ b> B is large, the flexible continuous fiber reinforcing material 10 as described above is disposed in the cutting groove 30 to form the floor slab shape. The arrangement of the combined continuous fiber reinforcing material 10 can be easily achieved, and the concrete structure can be reinforced effectively and easily.

Performance test The following experiment was conducted in order to examine the performance of a concrete slab to which the reinforcing method of the present invention was applied.

Using the strip-shaped continuous fiber reinforcing material 10S described in the specific example 1, the concrete slab was reinforced by the procedure described in the first example. The specifications and the like of the strip-shaped continuous fiber reinforcing material 10S used were as follows.
Continuous fiber bundle (11A)
Reinforcing fiber: High-strength carbon fiber Average diameter of fiber: 7 μm
Number of bundles of fibers: 24,000 Number of continuous fiber bundles: 48 Continuous gap between fiber bundles (g): 5.3 mm
Strip-like continuous fiber reinforcement (10S): Width (W) 250mm, Length (L) 25mm
Continuous fiber reinforcement after resin impregnation (10)
Resin R (adhesive 40): epoxy resin resin impregnation amount: 25% by weight
Nominal outer diameter (d) of continuous fiber reinforcement (10): 15 mm
Nominal cross section of rod (Af): 176 mm ²
Young's modulus (Ef): 60 GPa
Tensile strength: 850 N / mm ²

  In order to install the continuous fiber reinforcing material 10, the cutting groove 30 having a square cross-sectional shape having a width (W1) of 15 mm and a depth (H1) of 15 mm in FIG. As shown in FIG. 2 (a) and the like, it was formed by cutting with a diamond cutter at a pitch P = 125 mm in a direction perpendicular to the floor slab support (bridge axis direction) of the lower surface 1B of the concrete floor slab 1.

  The strip-shaped continuous fiber reinforcing material 10S having the above dimensions is shaped while being reduced from the tip, and the two-component mixed room temperature curing type putty-like epoxy resin as the matrix resin R is brushed. It was impregnated and inserted while being pressed into the cutting groove 30 sequentially from the tip. Such work was easy to handle the belt-like continuous fiber reinforcing material 10S, and the workability was extremely good. Thereafter, the resin is cured by leaving it to stand for 6 hours, the resin R also functions as the fixing agent 40, the continuous fiber reinforcing material 10 that is an FRP material is fixed in the cutting groove 30, and the continuous fiber reinforcing material 10 is The floor slab 1 was fixed integrally.

The tensile rigidity Sf per unit width of the concrete slab 1 reinforced with such a configuration is as follows. Note that nf = 1 / P. Therefore,
Sf = Ef × Af / P = 84.5 kN / mm

  From this, it was found that the reinforcing method of the present invention achieves a sufficient reinforcing effect for the concrete floor board.

(Operational effect of the reinforcing method of the present invention)
It is as follows if the effect of this invention implemented as mentioned above is demonstrated collectively.

  The method for reinforcing a concrete structure according to the present invention is a method of installing and fixing a continuous fiber reinforcing material in a narrow groove. It is easy to visually check the state, and moisture in the concrete structure is easily discharged, so there is no risk of water stagnation. In addition, the surface treatment area of the concrete surface is small and the installation area of the reinforcing material is small, so the construction period can be shortened and the construction cost can be reduced, and the continuous fiber reinforcing material is firmly fixed in the groove provided in the concrete. A high reinforcing effect can be obtained even for a structure whose surface layer is weakened.

  For example, in concrete floor slabs, fatigue deterioration of concrete structures is accelerated after the cracks in the concrete generated in the direction of the floor slabs penetrate from the lower surface to the upper surface and form a beam. Degradation of the slab is promoted when cracking occurs. Therefore, by fixing the continuous fiber reinforcing material in the direction perpendicular to the floor slab support on the lower surface of the beamed floor slab, it is possible to restore the slab continuity and improve the fatigue durability. The arrangement direction of the continuous fiber reinforcing material may be one direction orthogonal to the main cracking direction, or may be two directions, a right angle direction between floor slab branches and a direction between floor slab branches.

  In the present invention, for example, the belt-like continuous fiber reinforcing material 10S as the continuous fiber reinforcing material 10 has flexibility, and is easily reduced in the width direction and installed in the cutting groove with extremely good workability. be able to. Further, the continuous fiber reinforcing material 11 to be used has flexibility before being cured and can be compressed in the cross-sectional direction, so that the depth of the cutting groove can be reduced. It is possible to prevent damage to existing reinforcing bars by setting the depth to within the cover depth.

  Also, if the surface of the concrete structure is uneven, the flexible continuous fiber reinforcement is placed and then the sticking agent or the matrix resin of the continuous fiber reinforcement is cured to match the shape of the structure. The fiber reinforcement can be easily arranged.

  In the continuous fiber sheet bonding method and the steel plate bonding method, it was difficult to use a concrete surface protector such as a water repellent or impregnating material on the bonding surface of the reinforcing material and the concrete in order to ensure the bonding strength. In the present invention, since the reinforcing material is embedded in the concrete, it is possible to use a concrete surface protection work such as silane-based water repellent and lithium nitrite press-fitting against ASR and frost damage on the concrete surface. Is effective not only for fatigue due to wheel load, but also for RC slabs that have undergone combined degradation with ASR, frost damage, and the like.

  In the present invention, since the continuous fiber reinforcement is firmly fixed in the groove formed in the concrete structure, the required structure can be obtained even if the continuous fiber reinforcement is not necessarily arranged in two directions but arranged in one direction. The life-prolonging effect can be obtained. Further, even when the tensile rigidity per direction is less than 45 kN / mm, the reinforcing effect can be obtained. In the conventional continuous fiber sheet bonding method and FRP plate bonding method, if the tensile stiffness of the continuous fiber reinforcing material is excessive, the adhesion shear stress on the bonding surface is excessive and the peeling fatigue progresses early, so there was an upper limit on the amount of reinforcement, In the present invention, since the reinforcing material is embedded in the groove, peeling does not occur. Therefore, it is possible to use the continuous fiber reinforcing material up to about 100 kN / mm, which has higher tensile rigidity than the conventional bonding method, and a higher structure. The life-prolonging effect can be obtained.

1 Concrete slab (concrete structure)
DESCRIPTION OF SYMBOLS 1a Floor slab concrete 2 Pavement 3 Main girder 10 Continuous fiber reinforcement 10S Strip-like continuous fiber reinforcement 10R Rope-like continuous fiber reinforcement 11 Continuous fiber wire 11A Continuous fiber bundle 11B Continuous fiber prepreg 30 Cutting groove 40 Adhesive agent 100 Main reinforcement 101 Arrangement Force rebar

Claims (20)

A flexible continuous fiber reinforcing material having a large number of continuous reinforcing fibers and an uncured resin installed in a narrow linear cutting groove formed on the surface of a concrete structure is provided in the cutting groove. The resin is cured at the same time, and the continuous fiber reinforcing material cured in the cutting groove is fixed in the cutting groove by a fixing agent,
A method for reinforcing a concrete structure characterized by the above. Providing at least one narrow linear cutting groove on the surface of the concrete structure;
The resin is impregnated with a flexible dry continuous fiber reinforcing material not impregnated with resin, and is pushed into the cutting groove and installed, and by curing the resin, the resin functions as a fixing agent, Fixing the continuous fiber reinforcement in the cutting groove;
A method for reinforcing a concrete structure characterized by the above. Providing at least one narrow linear cutting groove on the surface of the concrete structure;
A flexible dry continuous fiber reinforcing material not impregnated with resin is installed in the cutting groove, and then the resin is injected into the cutting groove to impregnate the continuous fiber reinforcing material with the resin. By curing, the resin functions as a fixing agent, and the continuous fiber reinforcing material is fixed in the cutting groove.
A method for reinforcing a concrete structure characterized by the above. When the cutting groove is formed on the lower surface or the side surface of the concrete structure, the dry continuous fiber reinforcing material is installed in the cutting groove, and then the opening of the cutting groove is covered with a lid member. And injecting the resin into the cutting groove from a resin injection port provided in the lid member,
The method for reinforcing a concrete structure according to claim 3. Providing at least one narrow linear cutting groove on the surface of the concrete structure;
Pre-applying a sticking agent in the cutting groove,
Before the fixing agent is cured, the resin is impregnated with a flexible dry continuous fiber reinforcing material that is not impregnated with the resin, and is pushed into a cutting groove to which the fixing agent is applied. By fixing the fixing agent, the continuous fiber reinforcing material is fixed in the cutting groove,
A method for reinforcing a concrete structure characterized by the above. Providing at least one narrow linear cutting groove on the surface of the concrete structure;
A continuous fiber reinforcement material of a flexible prepreg that is impregnated with resin but is in an uncured state is placed in the cutting groove, and the resin impregnated in the continuous fiber reinforcement material is cured, and then fixed in the cutting groove. Fixing the continuous fiber reinforcing material in the cutting groove by injecting an agent and curing the fixing agent;
A method for reinforcing a concrete structure characterized by the above. When the cutting groove is formed on the lower surface or the side surface of the concrete structure, after the impregnating resin of the continuous fiber reinforcing material installed in the cutting groove is cured, the opening of the cutting groove is a lid member. The continuous fiber reinforcing material is fixed in the cutting groove by injecting the fixing agent into the cutting groove from the fixing agent injection port provided in the cover member and curing the fixing agent. To
The method for reinforcing a concrete structure according to claim 6. Providing at least one narrow linear cutting groove on the surface of the concrete structure;
Pre-applying a sticking agent in the cutting groove,
Before the fixing agent is cured, a continuous fiber reinforcing material of a flexible prepreg that is impregnated with a resin but is in an uncured state is pushed into a cutting groove to which the fixing agent is applied, and is installed. And fixing the continuous fiber reinforcement in the cutting groove by curing the adhesive.
A method for reinforcing a concrete structure characterized by the above. The flexible continuous fiber reinforcing material is formed by arranging a plurality of continuous fiber wires formed of a plurality of continuous reinforcing fibers in a slender shape in the longitudinal direction, and the plurality of continuous fiber wires are mutually fixed to a wire material. Fixed in, and formed into an elongated strip,
The method for reinforcing a concrete structure according to any one of claims 1 to 8, wherein: The flexible continuous fiber reinforcing material is formed in an elongated strip shape by aligning a number of continuous reinforcing fibers in one direction and fixing the continuous reinforcing fibers to each other with a fixing material.
The method for reinforcing a concrete structure according to any one of claims 1 to 8, wherein:   The strip-shaped continuous fiber reinforcing material is reduced in the width direction by being contracted, wound or folded in the width direction, and is inserted and installed in the cutting groove. A method for reinforcing a concrete structure as described in 1. The flexible continuous fiber reinforcing material is produced by knitting a continuous fiber wire formed of a large number of continuous reinforcing fibers into a rope shape or a string shape,
The method for reinforcing a concrete structure according to any one of claims 1 to 8, wherein:   The resin is a thermosetting resin such as a room temperature curable or thermosetting epoxy resin, vinyl ester resin, MMA resin, unsaturated polyester resin, acrylic resin, or phenol resin; heat such as nylon, polyamide, PEEK, etc. The method for reinforcing a concrete structure according to any one of claims 1 to 12, wherein the method is a plastic resin; or a thermoplastic epoxy resin.   The fixing agent is a thermosetting resin such as an epoxy resin or an acrylic resin; a thermoplastic resin such as nylon, polyamide, or PEEK; or an organic material such as a thermoplastic epoxy resin, or a cement mortar, an expandable cement mortar, The concrete structure according to any one of claims 1 to 13, which is an inorganic material such as polymer cement mortar or gypsum, or a mixed material obtained by mixing the organic material and the inorganic material. Reinforcement method.   The reinforcing fiber is an inorganic fiber such as carbon fiber, glass fiber or basalt fiber; an organic fiber such as aramid fiber, vinylon fiber or polyethylene fiber; or a fiber of any one of metal fibers such as steel fiber or stainless fiber, Or it is a hybrid fiber which combined multiple types of these fibers, The reinforcement method of the concrete structure of any one of Claims 1-14 characterized by the above-mentioned.   The method for reinforcing a concrete structure according to any one of claims 1 to 15, wherein the Young's modulus of the continuous fiber reinforcement after resin impregnation and curing is 10 GPa to 600 GPa. The concrete structure is a concrete floor slab,
The continuous fiber reinforcing material is installed in any one of a direction perpendicular to a floor slab support or a direction between floor slab supports, or in both a direction perpendicular to the floor slab support and a direction between the floor slab supports. The method for reinforcing a concrete structure according to any one of items 1 to 16. The tensile stiffness S in one direction after the resin impregnation and curing of the continuous fiber reinforcing material in the reinforcement target range is such that the tensile stiffness Sf per floor slab unit width represented by the following formula is 30 to 100 kN / mm. The method for reinforcing a concrete structure according to claim 17.
Sf = Af × Ef × nf
Af: Nominal cross-sectional area of continuous fiber reinforcement per one piece (mm ² )
Ef: Young's modulus (GPa) in the axial direction of the continuous fiber reinforcement
nf: Number of arrangement per unit width of continuous fiber reinforcement (lines / mm)   A concrete structure reinforced by the method for reinforcing a concrete structure according to any one of claims 1 to 18. A continuous fiber reinforcing material used in the method for reinforcing a concrete structure according to any one of claims 1 to 18,
Flexibility characterized by having a large number of continuous reinforcing fibers and being in a dry state not impregnated with resin, or being impregnated with resin but uncured and having flexibility Continuous fiber reinforcement.