JP3779806B2 - Method for reinforcing concrete columnar body - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for reinforcing a civil engineering structure or a concrete columnar body of a building structure, such as a bridge pier, a subway middle pillar, or a building pillar.
[0002]
[Prior art]
Conventionally, as a method for reinforcing a structure such as a concrete pillar constructed by a reinforced concrete (RC) or a steel reinforced concrete (SRC), a concrete pillar has been used. There are a method of winding reinforced concrete around, a method of attaching a steel plate, a method of winding a carbon fiber sheet, and the like.
[0003]
The method of winding reinforced concrete (RC) has problems such as an increase in weight, a new cross-sectional area, and a long curing period and a long construction period for performing concrete placement on site. The method of affixing a steel plate requires the operations of welding the affixed steel plates together or joining them by bolting, and has a problem that the weight of the steel plate is heavy and workability is poor. The method of winding the carbon fiber sheet requires R processing (curved chamfering) in advance at the corner of the concrete column in order to avoid the bending or stress concentration of the carbon fiber when the carbon fiber is wound around the concrete column. In addition, there is a problem that it takes time to treat the surface of the concrete column surface to attach the carbon fiber sheet. In particular, in order to reinforce the central pillar of a subway, which requires a reduction in work time, a more efficient and low-cost reinforcement method is desired.
[0004]
[Problems to be solved by the invention]
In order to solve such a problem, as shown in FIGS. 9 and 10, the steel plate 1 (1A, 1B) and the carbon fiber sheet 10 are used, that is, the steel plate attaching method and the carbon fiber sheet winding method are combined. Reinforcing methods have been proposed. Briefly, it is as follows.
[0005]
According to this reinforcing method, the surface treatment for the surface of the concrete pillar 100 is not necessary. That is, in this reinforcing method, first, two steel plates 1 (1A, 1B) having both ends 3 bent at a right angle with a predetermined radius R and having a U-shaped cross section are prepared. The steel plates 1A and 1B are attached with bolts or the like from both sides of the column 100 so as to face each other. A gap G is provided between the steel plates 1A and 1B and the pillar 100. Further, the end portions 3 of the respective steel plates 1 </ b> A and 1 </ b> B cover the corners of the column 100 and extend to the other side surfaces of the column 100. However, the end 3 does not exist up to the center of the side surface of the column 100. In terms of reducing the weight of the steel plates 1A and 1B and improving workability, the length of the end extension is preferably as small as possible. Therefore, a separation portion (L) that does not cover the concrete surface exists between the end portions 3 of both the steel plates 1A and 1B.
[0006]
Subsequently, the carbon fiber sheet 10 is affixed on the surface of the edge part 3 of each steel plate 1A, 1B, covering the separation part (L) of both these steel plates. Both ends of the carbon fiber sheet 10 are further pasted by extending a predetermined distance along the curved surfaces of the steel plates 1A and 1B to the other side surfaces. Thereafter, non-shrink mortar is filled between the concrete surface, the steel plate and the carbon fiber sheet.
[0007]
According to this method, since the carbon fiber sheet 10 is affixed to the surfaces of the steel plates 1A and 1B attached to the concrete surface, no ground treatment is required for the concrete surface. Moreover, since the carbon fiber sheet 10 is affixed along the curved corners of the steel plates 1A and 1B, it is not necessary to perform R processing on the corners of the concrete columns.
[0008]
However, as a result of the research experiment of the present inventors, as the distance between the separated portions (L) formed at the ends of both steel plates in the ordinary carbon fiber sheet construction method increases, FIG. 9 and FIG. As shown in FIG. 10, when the carbon fiber sheet in this portion is loosened downward and inward, and the carbon fiber sheet 10 is loosened in the separated portion (L), the carbon fiber sheet is loosened due to this loosening. It was found that the stress transmission due to the hindrance was hindered, the reinforcement efficiency was lowered, and the desired reinforcement effect could not be obtained.
[0009]
Accordingly, the object of the present invention is to eliminate the need for the base treatment and corner treatment even for a columnar body such as a concrete rectangular column, and to shorten the work period and reduce the cost. A method for reinforcing concrete columnar bodies such as bridge piers, subway middle columns, and building columns, which can improve the restraining effect, improve proof stress and toughness, and achieve the desired reinforcement effect sufficiently. Is to provide.
[0010]
[Means for Solving the Problems]
The above object is achieved by the columnar body reinforcing method according to the present invention. In summary, according to the first aspect of the present invention, (a) the opposing surface of one of the concrete columnar bodies to be reinforced whose cross section is rectangular, the outer surface is curved in the circumferential direction of the concrete columnar body, Installing a precast molded product having a predetermined length in the axial direction of the concrete columnar body so that there are no corners on the outer periphery of the concrete columnar body after installing the precast molded product;
(B) (1) The continuous reinforcing fiber is wound around the outer periphery of the concrete columnar body on which the precast molded product is installed, and then the resin is applied to the outer surface of the concrete columnar body wound with the reinforcing fiber to strengthen the reinforcing member. Impregnating the fiber with resin, or
(2) Resin is applied to the outer periphery of the concrete columnar body on which the precast molded product is installed, and continuous reinforcing fibers are wound from above, and if necessary, the outside of the concrete columnar body on which the reinforcing fiber is further wound. Applying resin on the surface and impregnating the reinforcing fiber with resin,
Wrapping of reinforcing fibers and resin impregnation step,
(C) Next, a step of curing the resin impregnated in the reinforcing fiber,
A method for reinforcing a concrete columnar body is provided.
[0011]
According to the second aspect of the present invention, (a) the outer surface is curved in the circumferential direction of the concrete columnar body on both opposing surfaces of any of the concrete columnar bodies to be reinforced that have a rectangular cross section; Installing a precast molded product having a predetermined length in the axial direction so that there are no corners on the outer periphery of the concrete columnar body after the precast molded product is installed;
(B) a step of winding a continuous reinforcing fiber coated with a resin around the outer periphery of the concrete columnar body on which the precast molded product is installed;
(C) Next, a step of curing the resin,
A method for reinforcing a concrete columnar body is provided.
[0012]
According to the third aspect of the present invention, (a) the outer surface is curved in the circumferential direction of the concrete columnar body on both opposing surfaces of any of the concrete columnar bodies to be reinforced that have a rectangular cross section, Installing a precast molded product having a predetermined length in the axial direction so that there are no corners on the outer periphery of the concrete columnar body after the precast molded product is installed;
(B) (1) After the resin is applied to the surface of the reinforcing fiber sheet formed by arranging the reinforcing fibers in one direction on the support sheet to impregnate the reinforcing fibers with the resin, the precast molded product is installed. Paste it on the outer peripheral surface of the concrete columnar body,
(2) A resin is applied to the outer peripheral surface of the concrete columnar body, a reinforcing fiber sheet is attached thereon, and pressed against the outer peripheral surface of the concrete columnar body, so that the reinforcing fiber is impregnated with the resin, and if necessary Further, apply a resin to the surface of the reinforcing fiber sheet, or
(3) A primer is applied to the outer peripheral surface of the concrete columnar body, a reinforcing fiber sheet is applied from above, and then a resin is applied to the reinforcing fiber sheet to impregnate the reinforcing fibers.
Winding of the reinforcing fiber sheet and resin impregnation step,
(C) Next, a step of curing the resin impregnated in the reinforcing fiber,
A method for reinforcing a concrete columnar body is provided.
[0013]
According to the fourth aspect of the present invention, (a) the outer surface is curved in the circumferential direction of the concrete columnar body on both opposing sides of any of the concrete columnar bodies to be reinforced that have a rectangular cross section, Installing a precast molded product having a predetermined length in the axial direction so that there are no corners on the outer periphery of the concrete columnar body after the precast molded product is installed;
(B) If necessary, a primer is applied to the outer peripheral surface of the concrete columnar body, and then a fiber reinforced prepreg formed by impregnating a resin into reinforcing fibers arranged in one direction is installed with the precast molded product. A step of attaching to the outer peripheral surface of the concrete columnar body,
(C) Next, a step of curing the resin impregnated in the reinforcing fiber,
A method for reinforcing a concrete columnar body is provided.
[0014]
In each of the above inventions, according to one embodiment, the precast molded product of the present invention can be precast concrete.
[0015]
Preferably, mortar can be applied to the outer surface of the columnar body around which the reinforcing fibers are wound, or a resin can be sprayed to finish.
[0016]
Preferably, the reinforcing fiber is any fiber selected from carbon fiber; glass fiber; metal fiber such as boron, titanium, and steel; organic fiber such as aramid, polyester, and nylon; It is a hybrid type in which multiple types of fibers are mixed. The resin includes at least a room temperature curable epoxy resin, a thermosetting epoxy resin or a polyester resin; a polyamide resin or a polycarbonate resin; or a radical reaction resin such as MMA.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a concrete columnar reinforcing method according to the present invention will be described in more detail with reference to the drawings. Referring to FIGS. 1 to 3, the reinforcing method of the present invention is a concrete rectangular column 100 such as a middle column of a subway whose cross section is rectangular, and in this embodiment is a square (W1 = W2) cross section. The case where it applies to is demonstrated.
[0018]
According to the present invention, a precast molded product 20 that is prepared in advance according to the cross-sectional dimension of the concrete rectangular column 100 is fitted to each side surface around the concrete rectangular column 100. The precast molded product 20 is a curved surface whose outer surface 20A is curved in the circumferential direction of the concrete rectangular column 100, and the other surface 20B adapted to the concrete rectangular column 100 is a flat surface in this embodiment, and its width (W). Is the same as the width (W1 = W2) of the concrete rectangular column 100. Moreover, the length (L) along the axial direction of the concrete pillar 100 of the precast molded product 20 is set to various dimensions as required. The precast molded product 20 is produced in advance at an existing factory or a temporary factory near the site. Usually, the precast molded product 20 is precast concrete, and is made of ordinary concrete, lightweight aggregate concrete, cellular concrete, or the like. As shown in FIG. 2, the precast concrete 20 is fixed and installed on each side surface of the concrete rectangular column 100 using an adhesive or a bolt (not shown).
[0019]
The circumferentially outer curved surface of the concrete column 100 defined by each precast concrete 20 fixed and installed on each side surface of the concrete rectangular column is a continuous closed curved surface having no step. For example, when the concrete pillar 100 has a square (W1 = W2) cross section as in this embodiment, the outer curved surface defined by each precast concrete 20 after the precast concrete 20 is attached. The cross-sectional shape is circular, as will be understood with reference also to FIG. Further, as shown in FIG. 4, in the case of the concrete pillar 100 having a rectangular (W1> W2) cross section, the cross section of the outer curved surface defined by each precast concrete 20 after the precast concrete 20 is attached. The shape is an ellipse.
[0020]
In the above description, the precast concrete 20 is installed on each side of the concrete rectangular column 100. However, as shown in FIG. 5, for example, the precast concrete 20 is only on one side of the concrete rectangular column 100 facing each other. Can be installed. As shown in FIG. 5, in the case of a concrete rectangular column 100 having a rectangular cross section, it is preferable to omit the opposing long side precast concrete 20 in terms of miniaturization of the precast concrete 20.
[0021]
As described above, when the precast concrete 20 is installed on a desired side surface of the concrete rectangular column 100 using an adhesive or a bolt, the reinforcing fiber 30 such as continuous carbon fiber is wound around the outer peripheral surface. At this time, the reinforcing fiber 30 may be wound so as to form a plurality of layers by reciprocally winding the outer surface of the precast concrete 20 over a predetermined width in the axial direction as necessary.
[0022]
The carbon fibers 30 are deformed along the curved surfaces defined by the respective precast concretes 20 and, in some cases, the concrete pillars 100, are in close contact with each other, and the fibers do not break when wound. At this time, although not essential, it is preferable to apply a primer to the surface of the precast concrete 20. Thereafter, the surface around which the carbon fiber 30 is wound is impregnated with a matrix resin, and is cured by heating as necessary.
[0023]
As the carbon fiber 30, a PAN-based fiber, a pitch-based fiber, or the like can be used. The physical properties of the carbon fiber are preferably 1.5 × 10 ^{6 to} 7.0 × 10 ⁶ kgf / cm ² , and The tensile strength is 5000 to 70000 kgf / cm ^2, and the basis weight of the carbon fiber is preferably 10 to 1000 g / m ² .
[0024]
Reinforcing fiber 30 is not limited to carbon fiber, and glass fiber; metal fiber such as boron, titanium, and steel; organic fiber such as aramid, polyester, and nylon; If necessary, a plurality of such fibers can be mixed and used as a hybrid type. In addition, as the matrix resin, a thermosetting resin such as a room temperature curing type or a thermosetting type epoxy resin or a polyester resin, a thermoplastic resin such as a polyamide resin or a polycarbonate resin, and MMA as required. Those containing a radical reaction system resin can be used.
[0025]
After the impregnated resin is cured, the surface on which the reinforcing fibers 30 such as carbon fibers are wound can be finished by applying finish mortar or spraying paint or the like.
[0026]
As described above, according to the reinforcing method of the present invention, by installing the precast molded product 20 on the concrete column 100, there is no corner on the outer peripheral surface around which the reinforcing fiber 30 is wound. R processing of the corner | angular part of the concrete pillar 100 conventionally performed becomes unnecessary. Moreover, compared with the method of winding up reinforced concrete (RC), it is not necessary to place concrete on site, the curing period is short, and the workability is good.
[0027]
In addition, according to the present invention, the cross section surrounded by the continuous fiber 30 is changed from a rectangular shape of the concrete rectangular column 100 to a circular shape, an elliptical shape, or an oval shape by using a precast molded product. As a result, significant improvement in toughness can be expected.
[0028]
According to the reinforcing method of the present invention, as shown in FIG. 6 (A), it can also be applied to the entire concrete column 100, and as shown in FIG. It can also be applied to. In particular, when only reinforcing toughness is intended, as shown in FIG. 6 (B), the reinforcing range is limited to the upper and lower regions of the concrete pillar 100, so that the inner space can be reinforced not so much. The construction period can be shortened.
[0029]
Example 2
In Example 1, the reinforcing fiber 30 such as continuous carbon fiber is wound around the outer peripheral surface of the precast concrete 20 installed on the concrete rectangular column 100, and then the matrix resin is impregnated on the surface around which the reinforcing fiber 30 is wound, Although described as what hardens | cures, apply | coat matrix resin to the outer peripheral surface of the precast concrete 20 (in the case shown in FIG. 5, also to the outer peripheral surface of the concrete rectangular pillar 100), and wind up the reinforcement fiber 30 continuously. You can also. If necessary, a matrix resin may be applied to the surface around which the reinforcing fibers 30 are wound. Thereafter, the matrix resin is cured by heating as necessary.
[0030]
The same reinforcing fibers 30 and matrix resin as described in Example 1 can be used, and the same method as in Example 1 can be used.
[0031]
According to the present embodiment, the same effect as that of the first embodiment can be achieved.
[0032]
Example 3
In Examples 1 and 2, the reinforcing fiber 30 such as continuous carbon fiber is wound around the outer peripheral surface of the precast concrete 20 installed on the concrete rectangular column 100, and then impregnated with a matrix resin, or the precast concrete 20 or the like. The matrix resin is applied to the outer peripheral surface of the resin, and the reinforcing fiber is wound around the resin-coated surface. However, the reinforcing fiber 30 is impregnated with the matrix resin in advance, and the outer peripheral surface of the precast concrete 20 or the like is impregnated with the resin. The reinforcing fiber 30 can also be wound. In this case, it is preferable to apply a primer to the precast concrete surface or the like around which the reinforcing fiber 30 is wound. The matrix resin impregnated with the reinforcing fibers is cured after the reinforcing fibers 30 are wound around the outer peripheral surface of the precast concrete 20.
[0033]
The same reinforcing fibers 30 and matrix resin as described in Example 1 can be used, and the same method as in Example 1 can be used.
[0034]
According to the present embodiment, the same effect as that of the first embodiment can be achieved.
[0035]
Example 4
In Example 1, the reinforcing fiber 30 such as continuous carbon fiber is wound around the outer peripheral surface of the precast concrete 20 installed on the concrete rectangular column 100. However, as shown in FIG. Can also be wound.
[0036]
8 (a) and 8 (b), an example of the reinforcing fiber sheet 50 is shown. The reinforcing fiber 30 is arranged in one direction on the support sheet 51 via an adhesive 52, for example. Formed.
[0037]
As the support sheet 51, glass cloth, glass paper (nonwoven fabric), aramid fiber cloth, aramid nonwoven fabric or the like is used. The thickness of the support sheet 51 is 1 to 500 μm, preferably 5 to 100 μm, and the thickness of the adhesive 52 is 1 to 100 μm, preferably 10 to 30 μm. The total thickness of the reinforcing fiber sheet 50 is about 10 to 100 μm.
[0038]
As a method of installing the reinforcing fiber sheet 50 on the outer peripheral surface of the precast concrete 20 (in the case shown in FIG. 5 also on the outer peripheral surface of the concrete rectangular column 100),
(1) A matrix resin is applied to the surface of the reinforcing fiber sheet 50, the reinforcing fibers 30 are impregnated with the resin, and then attached to the outer peripheral surface of the precast concrete 20.
(2) A matrix resin is applied to the outer surface of the precast concrete 20, and a reinforcing fiber sheet 50 is stuck thereon and pressed against the precast concrete surface 20 to impregnate the reinforcing fibers 30 with the resin. If necessary, a resin can be further applied to the surface of the reinforcing fiber sheet 50.
(3) A primer is applied to the outer surface of the precast concrete 20, a matrix resin is primed thereon, a reinforcing fiber sheet 50 is pasted thereon, and then the reinforcing fiber sheet 50 is overcoated with a matrix resin to reinforce the reinforcing fiber. 30 is impregnated. There is a way.
[0039]
The reinforcing fiber sheet 50 can be a continuous long one wound around a concrete pillar by a predetermined number of turns, but a plurality of sheets having a length shorter than the concrete circumferential length are used, and the end of each sheet is A method may be employed in which a predetermined number of sheets are stacked so as to overlap each other, and are stacked so as to form a plurality of layers as necessary. From the viewpoint of workability, for example, the reinforcing fiber sheet 50 cut into dimensions of a width of 20 to 50 cm and a length of 1 to 2.5 m is convenient.
[0040]
The matrix resin impregnated in the reinforcing fibers 30 is cured after the reinforcing fibers 30 are wound around the outer peripheral surface of the precast concrete 20.
[0041]
The same reinforcing fibers 30 and matrix resin as described in Example 1 can be used, and the same method as in Example 1 can be used.
[0042]
According to the present embodiment, the same effect as that of the first embodiment can be achieved.
[0043]
Example 5
In Example 4 described above, the embodiment in which the reinforcing fiber sheet 50 not impregnated with the matrix resin is used has been described. However, a release paper is used instead of the support sheet 51 in the reinforcing fiber sheet 50, and the top of the release paper is used. In addition, a fiber-reinforced prepreg sheet (not shown) well known to those skilled in the art can be used in which the reinforcing fibers 30 are arranged in one direction and are preliminarily impregnated with a matrix resin to be in a semi-cured state.
[0044]
The fiber-reinforced prepreg sheet is preferably attached to the outer peripheral surface of the precast concrete 20 to which the primer is applied (in the case of the outer peripheral surface of the concrete rectangular column 100 in the case shown in FIG. 5).
[0045]
The fiber-reinforced prepreg sheet can be wound around the concrete column by a predetermined number of turns while peeling the release paper from the continuous semi-cured fiber-reinforced prepreg, but as in the case of the reinforcing fiber sheet of Example 4, A plurality of sheets having a length shorter than the concrete circumference can be used, and the end portions of each sheet can be overlapped with each other, and a predetermined number of sheets can be laminated and wound in a plurality of layers as necessary. . From the viewpoint of workability, for example, a reinforcing fiber prepreg sheet cut to a size of 20 to 50 cm in width and 1 to 2.5 m in length is convenient.
[0046]
The semi-cured matrix resin impregnated with the reinforcing fibers is cured after the fiber-reinforced prepreg is wound around the outer peripheral surface of the precast concrete 20.
[0047]
The reinforcing fiber 30 can be the same as that described in Example 1, and the matrix resin is at least a thermosetting matrix resin such as a room temperature curable epoxy resin, a thermosetting epoxy resin, or a polyester resin. Is preferred.
[0048]
According to the present embodiment, the same effect as that of the first embodiment can be achieved.
[0049]
【The invention's effect】
As described above, the method for reinforcing a concrete columnar body according to the present invention is such that the outer surface is curved in the circumferential direction of the concrete columnar body on both opposing surfaces of the concrete columnar body to be reinforced with a rectangular cross section. The precast molded product having a predetermined length in the axial direction of the concrete columnar body was installed, and after the precast molded product was installed, there was no corner around the outer periphery of the concrete columnar body, and then the precast molded product was installed. Since it is configured to wind continuous reinforcing fiber, reinforcing fiber sheet, fiber reinforced prepreg or the like around the outer periphery of the concrete columnar body, and then cure the resin impregnated in the reinforcing fiber before or after winding. Even for columnar bodies such as concrete rectangular pillars, the ground treatment and corner treatment are unnecessary, and the construction period is shortened. In addition, it is possible to reduce the cost and to improve the restraining effect of the reinforcing fiber, to improve the proof stress and toughness, and to achieve the desired reinforcing effect sufficiently. Can play.
[Brief description of the drawings]
FIG. 1 is a perspective view for explaining an embodiment of a concrete columnar reinforcing method according to the present invention.
FIG. 2 is a perspective view for explaining a method of installing a precast molded product on a concrete rectangular column.
FIG. 3 is a cross-sectional view of a concrete rectangular column reinforced in accordance with the present invention.
FIG. 4 is a perspective view of another embodiment illustrating a method for reinforcing a concrete columnar body according to the present invention.
FIG. 5 is a perspective view of another embodiment illustrating a method for reinforcing a concrete columnar body according to the present invention.
FIG. 6 is a front view illustrating a method for reinforcing a concrete columnar body according to the present invention.
FIG. 7 is a perspective view for explaining another embodiment of the concrete columnar body reinforcing method according to the present invention.
8A is a cross-sectional view of a reinforcing fiber sheet, and FIG. 8B is a perspective view of the reinforcing fiber sheet.
FIG. 9 is a perspective view of a concrete column for explaining a reinforcing method in which a conventional steel sheet attaching method and a carbon fiber sheet winding method are combined.
10 is a cross-sectional view of the concrete pillar shown in FIG.
[Explanation of symbols]
20 Precast molded product 30 Reinforced fiber 40 Finish (mortar, resin)
50 Reinforced fiber sheet 100 Concrete columnar body

Claims (8)

(A) Precast molding in which the outer surface is curved in the circumferential direction of the concrete columnar body and has a predetermined length in the axial direction of the concrete columnar body on either side of either side of the concrete columnar body to be reinforced that has a rectangular cross section The process of making sure that there are no corners around the outer periphery of the concrete columnar after installing the product and precast molded product,
(B) (1) The continuous reinforcing fiber is wound around the outer periphery of the concrete columnar body on which the precast molded product is installed, and then the resin is applied to the outer surface of the concrete columnar body wound with the reinforcing fiber to strengthen the reinforcing member. Impregnating the fiber with resin, or
(2) Resin is applied to the outer periphery of the concrete columnar body on which the precast molded product is installed, and continuous reinforcing fibers are wound from above, and if necessary, the outside of the concrete columnar body on which the reinforcing fiber is further wound. Applying resin on the surface and impregnating the reinforcing fiber with resin,
Wrapping of reinforcing fibers and resin impregnation step,
(C) Next, a step of curing the resin impregnated in the reinforcing fiber,
A method for reinforcing a concrete columnar body, comprising: (A) Precast molding in which the outer surface is curved in the circumferential direction of the concrete columnar body and has a predetermined length in the axial direction of the concrete columnar body on either side of either side of the concrete columnar body to be reinforced that has a rectangular cross section The process of making sure that there are no corners around the outer periphery of the concrete columnar after installing the product and precast molded product,
(B) a step of winding a continuous reinforcing fiber coated with a resin around the outer periphery of the concrete columnar body on which the precast molded product is installed;
(C) Next, a step of curing the resin,
A method for reinforcing a concrete columnar body, comprising: (A) Precast molding in which the outer surface is curved in the circumferential direction of the concrete columnar body and has a predetermined length in the axial direction of the concrete columnar body on either side of either side of the concrete columnar body to be reinforced that has a rectangular cross section The process of making sure that there are no corners around the outer periphery of the concrete columnar after installing the product and precast molded product,
(B) (1) After the resin is applied to the surface of the reinforcing fiber sheet formed by arranging the reinforcing fibers in one direction on the support sheet to impregnate the reinforcing fibers with the resin, the precast molded product is installed. Paste it on the outer peripheral surface of the concrete columnar body,
(2) A resin is applied to the outer peripheral surface of the concrete columnar body, a reinforcing fiber sheet is attached thereon, and pressed against the outer peripheral surface of the concrete columnar body, so that the reinforcing fiber is impregnated with the resin, and if necessary Further, apply a resin to the surface of the reinforcing fiber sheet, or
(3) A primer is applied to the outer peripheral surface of the concrete columnar body, a reinforcing fiber sheet is applied from above, and then a resin is applied to the reinforcing fiber sheet to impregnate the reinforcing fibers.
Winding of the reinforcing fiber sheet and resin impregnation step,
(C) Next, a step of curing the resin impregnated in the reinforcing fiber,
A method for reinforcing a concrete columnar body, comprising: (A) Precast molding in which the outer surface is curved in the circumferential direction of the concrete columnar body and has a predetermined length in the axial direction of the concrete columnar body on either side of either side of the concrete columnar body to be reinforced that has a rectangular cross section The process of making sure that there are no corners around the outer periphery of the concrete columnar after installing the product and precast molded product,
(B) If necessary, a primer is applied to the outer peripheral surface of the concrete columnar body, and then a fiber reinforced prepreg formed by impregnating a resin into reinforcing fibers arranged in one direction is installed with the precast molded product. A step of attaching to the outer peripheral surface of the concrete columnar body,
(C) Next, a step of curing the resin impregnated in the reinforcing fiber,
A method for reinforcing a concrete columnar body, comprising:   The method for reinforcing a concrete columnar body according to any one of claims 1 to 4, wherein the precast molded product is precast concrete. The method for reinforcing a concrete columnar body according to any one of claims 1 to 5 , wherein mortar is applied to the outer surface of the columnar body around which the reinforcing fibers are wound or resin is sprayed. The reinforcing fiber may be any fiber selected from carbon fiber; glass fiber; metal fiber such as boron, titanium, and steel; organic fiber such as aramid, polyester, and nylon; or a plurality of the fibers. The method for reinforcing a concrete columnar body according to any one of claims 1 to 6 , wherein the hybrid type is mixed with seeds. The resin, at least cold-setting epoxy resin, thermosetting epoxy resin or a polyester resin; polyamide resin or polycarbonate resin; or, according to any of claims 1-7 comprising a radical reaction resins such as MMA To reinforce concrete columnar body.

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