KR20080055073A - Method for reinforcing a concrete structure - Google Patents

Abstract

A method for reinforcing a concrete structure is provided to reduce hardening time and to prevent contamination of a reinforcement against water or sand by installing fiber reinforced plastics preformed with thermosetting resins and polyamide fiber at an outer peripheral surface of the structure. A method for reinforcing a concrete structure comprises the steps of; exposing and grinding a reinforcement object part of a buried structure(S120); correcting step height of the reinforcement object part, removing a defective part, and coating epoxy putty(S130); installing a sheet reinforcement which is preformed with thermosetting resins and polyamide fiber(S140); covering/boding the reinforcement object part with the reinforcement before the epoxy putty is hardened(S150); and burying the reinforcement object part(S160).

Description

Method for reinforcing a concrete structure

1 is a perspective view schematically showing the appearance of the reinforcing material wound on the concrete structure according to the present invention;

2a and 2b is a schematic view showing a reinforcement of the reinforcement method of the concrete structure according to the present invention;

3 is a flowchart illustrating an embodiment of a reinforcement method of a concrete structure according to the present invention;

Figure 4 is an enlarged cross-sectional view schematically showing an embodiment of the reinforcement method of the concrete structure according to the present invention;

5 is a flow chart for explaining another embodiment of a method of reinforcing concrete structures according to the present invention;

Figure 6 is an enlarged cross-sectional view schematically showing another embodiment of the reinforcement method of the concrete structure according to the present invention;

7 is a plan view and an enlarged side cross-sectional view schematically showing the planar heating element used in FIG.

8 is a flow chart for explaining another embodiment of a method of reinforcing concrete structures according to the present invention; And

9 is a flowchart illustrating a reinforcement method of a conventional concrete structure.

〈Signs for Main Parts of Drawings〉

100, 200, 300: reinforcement method 110: telephone pole

120: primer 130: epoxy putty

140: reinforcement 150: soil

160: plane heating element 162: heat generating paper

164: copper foil 166: insulating film

168: wires

The present invention relates to a reinforcement method of a concrete structure, and more particularly, in a reinforcement method of a concrete structure that reinforces a lower portion of a concrete structure in which a lower portion thereof is embedded in soil, that is, a reinforcement target portion, reinforcement may be completed within a short time. At the same time, the present invention relates to a reinforcement method of a concrete structure in which the reinforcement is not contaminated by foreign matter such as water or sand during construction.

In general, concrete structures such as telegraph poles, piers, and piles, which are partially embedded in the soil, are built with underground parts embedded in the ground, such as roads. In the case of reinforcement, at least the ground around the buried reinforcement site is dug and reinforcement works are completed.

 For example, a method of impregnating and adhering a reinforcement on the surface of a concrete structure at a construction site, and embedding it in the soil after the adhesive resin and the reinforcement have been cured.

However, this method requires several days for the adhesive and the reinforcing material to harden, and when the resin is not completely cured, soil and sand stick to the adhesive, resulting in incomplete molding (FRP). As a result, the reinforcing effect of the reinforcing material may be reduced, as well as the adhesive resin and the reinforcing material should be left to harden for several days until the reinforcing material is cured, thereby increasing the possibility of contamination with water or rainwater.

Therefore, in order to solve the above-mentioned conventional problems, a method of covering the outer periphery of the adhesive portion with a synthetic resin film and embedding soil before the resin is cured after reinforcing fiber sheet bonding is used, and one such example is disclosed in Japanese Laid-Open Patent Publication. It is disclosed in 2002-89082, "Reinforcement method of embedded concrete columnar body in soil," and a flowchart of such a method is shown in FIG.

Referring to this, the conventional reinforcement method of the concrete buried concrete buried in the soil (1) is a method for reinforcing the pole pole embedded in the ground in the ground, digging the root to the extent that the concrete pole pole does not fall in the ground, the preparation stage (S10), performing a skeleton treatment with a disk sander, etc. (S20), applying a primer (S20), the first step of applying an adhesive resin (S30), impregnated by reinforcing the reinforcing fibers and thermosetting resin on the outer circumferential surface of the body pole, and then curing ( S40), covering the outer circumferential surface of the bobbin fiber with a synthetic film (S50), the step of reinforcing construction of the vicinity of the concrete pole, characterized in that the step of filling up the adhesive resin before curing (S60).

However, the reinforcement method (1) of the buried concrete columnar body in the soil according to the prior art described above is a method of impregnating and adhering a thermosetting resin to a reinforcing fiber at a construction site and attaching it to a telephone pole. By impregnating and bonding the fibers and curing them, the construction period is not only long, but the outer surface of the reinforcing fibers is covered with a synthetic resin film, but it is not possible to maintain a complete sealing state. By penetrating into the adhesive resin and contaminated, there was a problem that the reinforcing effect by the reinforcing fiber is reduced.

In addition, when the air temperature drops below zero, as in winter, the time for curing the adhesive resin becomes longer, thereby increasing the possibility of contamination from the outside and at the same time increasing the construction period, thereby increasing the construction cost.

The present invention has been made to solve the problems of the prior art as described above, the object of which is to reduce the construction period required for reinforcement at the same time when the need for reinforcement due to the aging of the concrete structure or increase in burden load, etc. The present invention provides a method of reinforcing concrete structures that prevents contaminants from being contaminated by other contaminants.

In order to achieve the above object of the present invention, in the method of reinforcing concrete structures embedded with a part of the present invention, (a) exposing and polishing the reinforcement target portion of the embedded structure, and (b) step of the reinforcement target portion Applying epoxy putty by performing cross-sectional repair by removing defective parts of corrected and cross-sectional defects, and (c) using any one or more of thermosetting resins such as epoxy resins, polyester resins and vinyl esters, and polyamide fibers. (B) wrapping and bonding the reinforcement object with the reinforcing material before the epoxy putty is cured, and (e) curing the epoxy putty after the reinforcing material is cured. It provides a method of reinforcing concrete structures comprising the step of embedding the joined reinforcement object.

In addition, in the present invention, between the step (a) and (b), (f) characterized in that it further comprises the step of applying a primer material to the reinforcement target portion.

In addition, in the present invention, between the step (d) and (e), (g) characterized in that it further comprises the step of providing a planar heating element in close contact with the outer surface of the reinforcing material.

In addition, in the present invention, between (g) and (e) step, (h) is characterized in that it further comprises the step of curing the epoxy putty by applying electricity to the planar heating element.

In the present invention, the step (h) and (e), characterized in that it further comprises the step of (i) removing the planar heating element.

In addition, in the present invention, the planar heating element is composed of a heat generating paper mixed with carbon fiber and pulp, a connection terminal provided at both ends of the heat generating paper to receive power, and an insulating film provided on the outer surface of the heat generating paper. It is done.

In the present invention, the reinforcing material is characterized in that the fiber reinforced plastics (fiber reinforced plastics).

The features and advantages of the present invention will become more apparent from the following detailed description based on the accompanying drawings. Prior to this, the terms or words used in this specification and claims are not to be interpreted in a conventional and dictionary sense, and the inventors may appropriately define the concept of terms in order to best explain their invention in the best way possible. It should be interpreted as meaning and concept corresponding to the technical idea of the present invention based on the principle that the present invention.

Hereinafter, with reference to the accompanying drawings a preferred embodiment of the reinforcing method of the concrete structure according to the present invention will be described in detail.

First, Figure 1 is a perspective view schematically showing the appearance of the reinforcing material wound on the concrete structure according to the present invention, Figures 2a and 2b is a schematic view showing a reinforcement of the reinforcing method of the concrete structure according to the present invention.

As shown in Figure 1, the reinforcement method of the concrete structure according to the present invention can reduce the construction period required for reinforcement at the same time when the concrete structure needs to be reinforced due to aging or increase in burden load, etc. by the other contaminants It is characterized by the additional construction of the reinforcement to prevent contamination.

The reinforcing material 140 used in the reinforcement method of the concrete structure according to the present invention is composed of an aromatic polyamide fiber having a higher tensile strength than concrete and thermosetting resin such as epoxy resin, polyester resin, vinyl ester, and the like beforehand molding in a separate factory. This product is a fiber-reinforced plastic (FRP) that has been preformed and is pre-cured by using a prepreg in which a reinforcing fiber and an impregnating resin are already combined, or by using a room temperature-curable resin in a reinforcing fiber fabric. Use

At this time, the reinforcing material 140, as shown in Figure 2a and 2b, using a product cured by impregnating a curable resin in a thin reinforcing fiber fabric of less than 1mm to wrap along the surface of the structure, the reinforcing fiber than concrete Long fiber with high tensile strength is used as a raw material, and is woven in one direction or in both directions.

The preformed reinforcement 140 is bonded to wrap around the outer circumferential surface of the concrete structure using the epoxy putty 130 used for step correction and adhesion, unlike the reinforcement that was impregnated and bonded in the existing construction site. This eliminates the time to cure and shortens the construction period.

In addition, since the existing reinforcement is not hardened when bonded to the concrete structure, the possibility of contamination caused by the penetration of water or sand into the reinforcement, the present invention is a pre-formed reinforcement (fiber-reinforced plastic 'FRP') 140 By using it, foreign substances such as water or sand may be mixed during construction, thereby preventing the possibility of contamination.

Referring to the embodiment 100 of the reinforcement method of the concrete structure according to the present invention using the reinforcement as described above.

Figure 3 is a flow chart for explaining an embodiment of the reinforcement method of the concrete structure according to the invention, Figure 4 is an enlarged cross-sectional view schematically showing an embodiment of the reinforcement method of the concrete structure according to the present invention.

First, the concrete telegraph pole 110 of the concrete structure to help the examiner's understanding will be described as an example.

First, to secure a work space by digging the bottom of the concrete pole pole 110 to be reinforced, that is, the soil 150 around the reinforcement target portion (S110).

That is, by selecting the concrete poles 110 to be reinforced among the concrete poles buried in the road, etc. by connecting the poles around the poles 110 so that the poles 110 do not fall during construction, by preparing a safety countermeasure soil 150 Digging the soil 150 around the reinforcement target portion of the telephone pole 110 buried in it to perform the reinforcement work.

Subsequently, using a polishing tool such as a grinder or a disk sander, the surface around the reinforcement target portion of the telephone pole 110 is ground to grind portions previously contaminated with soil or water, and then apply a primer 120 thereon. To dry. (S120)

In the polishing and primer 120 coating operations, since the surface of the reinforced target portion of the concrete pole 110 is contaminated by water or soil, the contaminated portion, that is, the surface strength is weakened, fouling, release agent layer, ray Grind the tungs layer, etc. so that the surface without fragile parts or fouling appears, the primer 120 to increase the adhesion so that the corrosion of the concrete pole 110 and the epoxy putty 130 to be described later is firmly attached To apply. At this time, the primer 120 applied to the reinforcement object after the polishing operation is preferably completely dried and then proceeds to the step of applying the epoxy putty 130 to be described later.

Subsequently, the surface of the reinforcement target portion of the polished concrete pole (110) has a large recessed or aged portion, that is, a portion such as cracks or cracks fall off the concrete surface, such as epoxy putty (130) to fill the filling material Filling makes the surface flat (S130).

That is, by using the polishing tool to grind the portion contaminated by the various contaminants while being embedded in the soil 150 for a long time, the epoxy puffy (130) is filled in the ruggedly reinforced reinforcement object (130) A cross section repair operation is performed in which a cross section is repaired flat by filling a back plate).

Subsequently, thermosetting resins such as epoxy resins, polyether resins, vinyl esters, and the like, and a reinforcing member 140 in the form of a sheet pre-formed with polyamide fibers or the like are provided.

In other words, using a room-temperature-curable resin in the reinforcing fiber fabric pre-cured in a separate place, the reinforcement of a thin structure of less than 1mm thick to wrap the outer periphery of the structure having a small diameter, such as concrete pole 110 Reinforced plastic 'FRP' (140) is provided.

Subsequently, before the epoxy putty 130 applied to the reinforcement target portion of the concrete pole pole 110 is cured, the preformed reinforcement 140 is bonded (S150).

That is, the epoxy putty 130 coated with the telegraph pole 110 is formed by curing the reinforced reinforcement 140 including the aromatic polyamide fiber having a higher tensile strength than the concrete and thermosetting resin such as epoxy resin, polyester resin, and vinyl ester. Before the bend to wrap around the outer circumference of the pole 110 and fixed using a band or tape (T) and bonded.

Subsequently, when the epoxy putty 130 applied to adhere and reinforce the reinforcing material 140 to the reinforcement object of the telephone pole 110 is completely cured, the reinforcement object is covered.

That is, by bonding the pre-formed reinforcing material 140, the reinforcing material hardening time that occurred by impregnating, adhering and curing the thermosetting resin to the reinforcing fiber in the existing construction site is not necessary, only to join the reinforcing material 140 When only the epoxy putty 130 for curing is completed because the bonding of the reinforcing material 140 can be covered in a short time it is possible to shorten the construction time.

On the other hand, Figure 5 is described with reference to the drawings as another embodiment 200 of the reinforcement method of the concrete structure according to the present invention.

Figure 5 is a flow chart for explaining another embodiment of the reinforcement method of the concrete structure according to the invention, Figure 6 is an enlarged cross-sectional view schematically showing another embodiment of the reinforcement method of the concrete structure according to the present invention, Figure 7 is 6 is a plan view and an enlarged side cross-sectional view schematically showing the planar heating element used in FIG. 6.

Referring to this, another embodiment of the reinforcement method 200 of the concrete structure according to the present invention is provided with a planar heating element 160 on the outer circumferential surface of the reinforcing material 140 to further shorten the time for curing the epoxy putty 130 Features.

As such, the reinforcement method 200 of the concrete structure shown in FIG. 5 installs a planar heating element 160 on the outer circumferential surface of the reinforcement 140 and heats the reinforcement 140 by applying electricity to further shorten the curing time. Except that since it is substantially the same as the embodiment 100 of the present invention shown in Figure 3, the description of the details except for the difference will be omitted.

In order to increase the curing rate of the epoxy putty 130 between the step (S150) and the step (S160) of bonding the preformed reinforcement 140, the planar heating element 160 in the form of a sheet on the outer peripheral surface of the reinforcement 140 It is provided with a wrap. (S260)

In other words, before the epoxy putty 130 for bonding the reinforcing material 140 to the outer peripheral surface of the reinforcement target part of the telephone pole 110 is hardened, the outer circumferential surface of the reinforcing material 140 is tightly wrapped and fixed with a sheet-like planar heating element 160. do.

As shown in FIG. 6, the planar heating element 160 is in the form of a sheet having a thickness of 1 mm or less including a heating paper 162 in which carbon fibers and pulp are mixed, a copper foil 164, and a thermal insulation film 166. Copper foil 164 is attached to both ends of the paper 162, and both sides of the heat generating paper 162 to which the copper foil 164 is attached are laminated with the insulating film 166 to prevent moisture permeation. Configuration.

The planar heating element 160 configured as described above is preferably a method for shortening the curing time of the epoxy putty 130 so as to radiate heat evenly over the entire surface. This is because the use of a heating wire like an electric blanket is a local heating method of the heating wire, so that the bonding site begins to cure from the vicinity of the heating wire, and the bonding site far from the heating wire is later hardened.

Subsequently, by applying electricity to the planar heating element 160 to heat the planar heating element 160 to cure the epoxy putty 130 applied to the reinforcement target portion to remove the planar heating element 160 (S270).

That is, when electricity is applied to the wire 168 connected to the copper foil 164 of the planar heating element 160, the temperature of the planar heating element 160 is increased to quickly cure the epoxy putty 130, and then the epoxy putty When the 130 is completely cured is to remove the planar heating element 160 surrounding the reinforcing material 140.

Here, the exothermic application temperature of the planar heating element 160 is 25 ℃ ~ 60 ℃, it is preferably heated to a temperature of 40 ℃ ~ 45 ℃, so that the epoxy putty 130 is uniformly cured over the entire area, epoxy The planar heating element 160 of the putty 130 may be separated and reused.

Subsequent to the above step, the finishing work to perform the cover work to fill the reinforcement target portion of the concrete pole pole 130. (S280)

Therefore, the epoxy putty used to bond the reinforcing material 140 to the telephone pole 110 by heating with the planar heating element 160 than the reinforcing method 100 according to an embodiment of the reinforcing method of the concrete structure of the present invention. It is possible to cure the 130 in a short time it is possible to further shorten the time required for reinforcement.

In addition, Figure 8 is a flow chart for explaining another embodiment 300 of the reinforcement method of the concrete structure according to the present invention, in order to further shorten the construction period as shown in Figure 5 the planar heating element 160 It may be used to cover the outer peripheral surface of the reinforcing material 140, and then immediately cover the soil 150, and then apply electricity to the planar heating element 160 to harden the bonding site.

As described above, the reinforcement method of the concrete structure according to the present invention is a reinforcement method for reinforcing the lower portion of the telegraph pole 110 embedded in the soil 150, that is, the reinforcement target portion of the telegraph pole 110, the soil 150 Reinforcement material (fiber-reinforced plastic 'FRP') which is ground by grinding the surface of concrete pole 110 embedded in the concrete and including thermosetting resin such as aromatic polyamide fiber and epoxy resin, polyester resin, vinyl ester, etc. By using the 140, not only the construction period can be shortened, but also by using the reinforcement material 140, which has already been molded, foreign substances such as water or sand can be mixed during construction, thereby preventing the possibility of contamination.

In addition, as another embodiment (200, 300) of the present invention, by wrapping the outer circumferential surface of the reinforcing material 140 with the planar heating element 160 and applying electricity to generate heat, it is possible to further shorten the time for curing the epoxy putty 130 If necessary, the outer circumferential surface of the reinforcing material 140 may be wrapped with the planar heating element 160, and then immediately covered with electricity, and then the electricity may be applied to cure the epoxy putty 130.

Here, using the tubular branch pipe of diameter 32cm, thickness 0.7cm, height 120cm instead of the concrete pole, the work was performed by the reinforcement method and the conventional reinforcement method of the present invention and compared the results.

First, the conventional reinforcing method is to start to cure in 20 minutes at 45 ℃ by mixing the main material and the curing agent 2: 1 at 50cm, 25 ℃ at a lower temperature of one branch of the same size pipe at a temperature of 25 ℃ Made of a material) and dried, and the adhesive resin for adhering the reinforcing sheet is not more than 1mm, and the base is coated with a primer using a material that starts to cure in 20 minutes at 20 ° C by mixing the main material and the curing agent 2: 1. The adhesive resin was overlaid immediately after the coating and the reinforcing material was impregnated and adhered to the branch pipe. As a reinforcing material, a carbon fiber sheet product of 0.2 mm or less was used. Thus, the construction time of the conventional method took about 2 days as a time for curing the reinforcing material and the adhesive resin except for the primer application and drying time.

Subsequently, the reinforcing method according to the present invention, after applying the same primer to the two of the same branch pipe and dried, the mixture of the putty putty applied to the surface of the branch pipe and wrapped the preformed reinforcing material (fiber-reinforced plastic) according to the present invention After fixing with a tape, one was cured by using a planar heating element, it took about 24 hours, and when it was cured wrapped around the planar heating element took about 6 hours. (At this time, the planar heating element was cut to 50cm in length and the temperature of the planar heating element was set to 45 ° C. at 220V.)

In addition, as a result of comparing the curing time of the epoxy putty used to bond the reinforcement, as a result of the conventional method took about 48 hours at 25 ℃, using the completed reinforcement takes 6 hours to reinforce concrete pole pole construction It was confirmed that the time can be very short.

As mentioned above, although the reinforcing method of the concrete structure of the present invention has been described with reference to the preferred embodiment of the present invention, it will be apparent to those skilled in the art that modifications, changes, and various modifications can be made without departing from the spirit of the present invention.

Reinforcement method of the concrete structure according to the present invention configured and acted as described above, when it is necessary to perform repair and reinforcement of a concrete structure embedded in the soil part of the aromatic polyamide fiber and epoxy resin, poly By using a reinforcing material (fiber-reinforced plastic 'FRP') pre-molded with a thermosetting resin such as ester and vinyl ester, the curing time and construction time can be shortened and economical reinforcing work can be performed.

Further, by using a preformed reinforcing material, it is possible to prevent the reinforcing material from being contaminated by foreign matter such as water or sand during construction.

Claims (8)

In the method of reinforcing concrete structures partially embedded, (a) exposing and polishing the reinforcement part of the embedded structure; (b) applying an epoxy putty by performing cross-sectional repair by removing step defects and defective sections of the reinforcement object; (c) providing at least one of thermosetting resins such as epoxy resins, polyester resins, vinyl esters, and the like, and reinforcing materials in the form of sheets preformed with polyamide fibers or the like; (d) wrapping and reinforcing the reinforcement object with the reinforcing material before the epoxy putty is cured; And (e) burying the reinforcement to which the reinforcing material is bonded after curing the epoxy putty; Reinforcement method of the concrete structure, comprising a. According to claim 1, Between (a) and (b), (f) reinforcing the concrete structure, characterized in that it further comprises the step of applying a primer material on the reinforcement object. The method of claim 1, wherein, between steps (d) and (e), (g) reinforcing the concrete structure, characterized in that it further comprises the step of providing a planar heating element in close contact with the outer surface of the reinforcing material. The method of claim 3, wherein between steps (g) and (e), (h) reinforcing the concrete structure, further comprising hardening the epoxy putty by applying electricity to the planar heating element. The method of claim 4, wherein, between the steps (h) and (e), (i) reinforcing the concrete structure, further comprising the step of removing the planar heating element. The method of claim 3, wherein after the step (g) immediately buried the reinforcement to be wrapped with the planar heating element, and applying electricity to the planar heating element further comprises the step of curing the epoxy putty of the concrete structure Reinforcement method. According to claim 3, wherein the planar heating element is made of a heat generating paper mixed with carbon fiber and pulp, the connection terminal is provided at both ends of the heat generating paper to receive power, and an insulating film provided on the outer surface of the heat generating paper. Reinforcement method of concrete structure. The method of claim 1, wherein the reinforcement material is fiber reinforced plastics.

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