JP2003321941A - Section repairing panel for prevention of deterioration of reinforced concrete structure and method for prevention of deterioration of reinforced concrete structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To repair a section of a part where a reinforced concrete structure is removed, and install electrodes for electrolytic corrosion protection at the same time, while solving a problem of such inefficiency in a conventional method of electrolytic corrosion protection that it takes much labor to install an anode and that there are many places requiring connection of the anode. <P>SOLUTION: A section repairing panel, having linear grooves formed on a surface of a panel plate at appropriate intervals and electrodes for electrolytic corrosion protection fixed to the linear grooves to project from the surface, is installed in a state that the electrodes face the part where the reinforced concrete structure is removed. Filler material is injected between the section repairing panel and the structure to repair the section, and then power is applied to the electrodes. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for preventing deterioration of a reinforced concrete structure by repairing or reinforcing the reinforced concrete structure and performing galvanic protection on a steel material such as a reinforcing bar embedded in the concrete.

[0002]

2. Description of the Related Art Reinforced concrete structures have been considered to be permanently immortal for some time, but in recent years, concrete for reinforced concrete structures has various reasons such as cold joints, neutralization, salt damage or poor construction. As a result, peeling and falling of concrete pieces and water leakage due to cracks have become a social problem.

Particularly, in a reinforced concrete structure in a salt damage area, salt adheres to the concrete surface. When the outside air dries with the salt content permeating inside the concrete, the water content evaporates, leaving only the salt content inside, and by repeating this process, the salt concentration is gradually concentrated. Thus, in a reinforced concrete structure, the reinforcing bars inside the concrete may rust over time, and the original usability and functionality of the structure may be lost. In addition, the reinforcing bar expands and peels off as concrete pieces, causing a third party injury.

As a countermeasure, the concrete standard specification (maintenance management edition) issued by the Japan Society of Civil Engineers indicates the standard construction method according to the appearance grade of the structure.

Table 1 shows the appearance grade of the structure and the state of deterioration.

[0006]

[Table 1]

Table 2 shows the appearance grade of the structure and countermeasures.

[0008]

[Table 2] ◎: Standard measures ○: Possible measures (○): Preventive measures

Table 3 shows the appearance grade and typical performance degradation of the structure.

[0010]

[Table 3]

[0011]

[0012]

Generally, in a salt-damaged area, when a reinforced concrete structure such as a bridge slab has insufficient load-carrying capacity due to an increase in wheel load due to salt damage, a reinforcing material such as a steel plate or FRP is used to maintain the functionality and usability. There is a method of adhering to. For girders and balustrades, in order to prevent peeling and peeling due to corrosion of reinforcing bars and cracks caused by materials, laminated glass fiber and synthetic fibers such as vinylon are laminated on site and repaired. As a material, there is a repair or reinforcement method that adheres to the concrete surface.

As a device for preventing corrosion of steel materials such as reinforcing bars in concrete due to salt, there is electrocorrosion.

As the cathodic protection method, the cathodic protection method using a linear anode and the cathodic protection method using a panel anode are well known.

As shown in FIG. 9, the method of cathodic protection using the linear anode is as follows: (a) the damaged portion of the reinforced concrete structure 11 is removed by chipping, and (b) the formwork 13 is installed in the removed portion 12, After injecting the injection material 14 to repair the cross section, (c)
The mold 13 is removed, grooves are formed on the surface at appropriate intervals, and the linear anode 3, which is an electrode for cathodic protection, is installed in this groove.

The method of cathodic protection by the panel anode is shown in FIG.
As shown in FIG. 5, a plurality of surface electrodes 23 in which the anode material 22 is integrated with the four sides of the panel material 21 are removed, the damaged portion is removed, and the sections are connected to a wide area on the surface of the reinforced concrete structure after the cross-section restoration and installed. This is what you do.

[0018]

However, the above-mentioned cathodic protection method has the following problems.

In the cathodic protection method using a linear anode, after repairing the cross section, the grooves 14 are formed at appropriate intervals at the locations, and the linear anodes are installed in the grooves 14, so that the working time as a whole is long. Moreover, since the anode part is exposed to the outside, the durability is poor.

In the case of cathodic protection using panel anodes, the workability is poor because there are many places where the anodes are connected between panels.

On the other hand, if the above-mentioned cathodic protection and the method of preventing deterioration of the concrete surface with a steel plate, a fiber molding plate or the like are used together, the following problems occur.

That is, if a concrete surface made of steel, glass fiber, or synthetic fiber such as vinylon is cross-bonded and covered with the concrete surface, even if the voltage of the electrode is increased, chlorine gas, etc. When the gas is generated, a gas blocking phenomenon occurs, and it becomes difficult for the current to flow from the electrode, and it may be impossible to supply an appropriate anticorrosion current to the steel material such as the reinforcing steel of concrete.

[0023]

Means for Solving the Problems As a result of intensive studies, the present inventor has solved the above-mentioned problems in a reinforced concrete structure, repaired a section of a removed part of the reinforced concrete structure, and installed an electrode for cathodic protection. The present invention has invented a cross-section restoration panel used in a method for preventing deterioration of a reinforced concrete structure that can be simultaneously constructed, and a degradation prevention method for a reinforced concrete structure using this cross-section restoration panel.

That is, the present invention is to prevent deterioration of a reinforced concrete structure in which a groove is formed on one surface of a panel plate at an appropriate interval, and an electrode for anticorrosion is projected and fixed to the groove in the groove. By providing a cross-section restoration panel for use, it was possible to simultaneously perform cross-section restoration of the removed part of the reinforced concrete structure and an electrode for cathodic protection.

Furthermore, by forming the panel plate of the cross-section restoration panel for deterioration prevention with a mortar plate containing cement as a main component, the gas blocking phenomenon due to the generation of chlorine gas and the like can be reduced.

Next, according to the present invention, on the reinforced concrete structure from which the damaged portion is removed, grooves are formed on one side of the panel plate at appropriate intervals, and electrodes for cathodic protection are formed on the grooves on the surface. Cross-section restoration panels that are projected and fixed are installed with a certain interval and the fixed surface for cathodic protection faces the structure, and injection material is injected between the structure and the cross-section restoration panel. By providing a method for preventing deterioration of a reinforced concrete structure in which the cross-section is repaired, and electric current is applied to the cathodic protection electrode after the cross-section is repaired, the drawbacks of cathodic protection by a linear anode and cathodic protection by a panel anode are eliminated and reinforced concrete is provided. It enabled the restoration of the cross section of the removed part of the structure and the simultaneous installation of electrodes for cathodic protection.

Furthermore, the cross-section restoration panel used in the method for preventing deterioration of a reinforced concrete structure is formed of a mortar plate containing cement as a main component to reduce the gas blocking phenomenon associated with the generation of chlorine gas and the like. Made possible.

By mixing a conductive material into the cross-section repairing injection material, the electrical function could be improved.

[0029]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described with reference to the drawings.

First, a cross-section restoration panel for preventing deterioration of a reinforced concrete structure according to the present invention will be described with reference to FIGS. 1 to 3.

The cross-section restoration panel 10 is provided with the groove 2 formed on one surface of the panel plate 1 at regular intervals, and the linear anode 3 which is an electrode for anticorrosion is fixed to the groove 2. The linear anode 3 is inserted along the groove 2, and the upper part thereof is projected above the surface,
A part is embedded and fixed by the filler 4 and the like. The end 3a of the linear anode 3 is for connecting a plurality of cross-section restoration panels 10. Reference numeral 5 is an anchor hole when the cross-section restoration panel 10 is attached to a reinforced concrete structure for preventing deterioration.

The panel plate 1 of the cross-section restoration panel 10 is
It is preferable to use a material that does not easily cause a gas blocking phenomenon, and in this embodiment, a mortar plate containing cement as a main component was used. Since this mortar version is porous,
Gas blocking phenomenon is less likely to occur. In addition, although the drawings are exaggerated to show the main parts and the dimensions are not expressed accurately, the dimensions of the cross-section restoration panel 10 in this embodiment are, by the way, 1800 mm in length, 900 mm in width, and 1 in thickness.
It is 5 mm, the groove center interval is 150 mm, and the groove width is 3 mm.

In this way, a cross-section restoration panel for preventing deterioration of the reinforced concrete structure is formed as a whole.

Next, a method for preventing deterioration of a reinforced concrete structure using this cross-section restoration panel will be described with reference to FIGS. 4 to 8.

First, as shown in FIGS. 4 (a) and 5,
The damaged portion of the reinforced concrete structure 11 to be subjected to the deterioration prevention method is removed by scraping. Reference numeral 12 is a removed portion, and 15 is a buried reinforcing bar.

Next, as shown in FIGS. 4 (b) and 6, the cross-section restoration panel 10 is kept in the removal part 12 at a constant distance from the structure 11, and the linear anode 3 is closer to the structure 11. The anchor 6 is attached through the anchor hole 5 so as to face, and the side-face formwork 13 is installed on all four sides by a known method. Here, the anchor 6 includes a male screw 6a, a female screw 6b, a nut 6c, and an outer cylinder 6d.
Is formed of an insulating material. After this, the injection hole 16
The injection material 14 is injected. The injection material 14 is preferably cement mortar mixed with a conductive material, for example, non-shrink mortar, polymer cement mortar, or conductive mortar.

When a plurality of cross-section restoration panels 10 are installed in the longitudinal direction, the end portions 3a of the linear anodes 3 are faced to each other and connected by spot welding 3b or the like as shown in FIG.

After the injection material 14 is cured, as shown in FIGS. 4 (c) and 7, the side frame 13 is removed, the female screw 6b and the nut 6c of the anchor 6 are removed if necessary, and the plastic bolt 6e is attached. . After that, the linear anode 3 is energized.

In this way, the method for preventing deterioration of the reinforced concrete structure is constructed as a whole. Of course, the present invention is not limited to the aspect described above.

[Title of Invention] Since the present invention is configured as described above, it has the following effects.

In any one of claims 1 to 5, a groove is formed after the cross section is repaired after removal of a damaged portion such as cathodic protection in a linear anode, and an electrode for electrocorrosion is embedded in the groove, or a panel is formed. Since it is possible to save the trouble of connecting the four anodes to each other as in the case of cathodic protection by anodes, and the cross-section restoration panel can be manufactured in the factory, the work efficiency in the field is extremely good.

In the first to fifth aspects, since the cross-section restoration panel also serves as the form, it is possible to restore the cross-section after removing the damaged portion and simultaneously install the electrode for cathodic protection.

In the first to fifth aspects, the durability is improved because the electrodes are not exposed to the outside.

In claim 2 and claim 4, since the panel plate is formed by the mortar plate containing cement as a main component, the panel plate becomes porous, so that the gas blocking phenomenon due to the generation of chlorine gas and the like can be reduced. .

In the fifth aspect, the electrical function can be improved by mixing a conductive material in the injection material.

[Brief description of drawings]

FIG. 1 is a plan view of a panel plate having a groove.

FIG. 2 is a plan view of a cross-section restoration panel.

3 is a cross-sectional view taken along the line AA of FIG.

FIG. 4 is a schematic cross-sectional view showing the procedure of a method for preventing deterioration of a reinforced concrete structure.

FIG. 5 is a partially enlarged schematic cross-sectional view showing a procedure of a method for preventing deterioration of a reinforced concrete structure.

FIG. 6 is a partially enlarged schematic cross-sectional view showing the procedure of a method for preventing deterioration of a reinforced concrete structure.

FIG. 7 is a partially enlarged schematic cross-sectional view showing the procedure of a method for preventing deterioration of a reinforced concrete structure.

FIG. 8 is a plan view showing an example of joining cross-section restoration panels.

FIG. 9 is a schematic cross-sectional view showing a procedure of a conventional method for preventing deterioration of a reinforced concrete structure.

FIG. 10 is a plan view showing a conventional panel anode.

[Explanation of symbols]

1 panel version 2 groove 3 Electrolytic electrodes 4 Filling material 5 anchor holes 6 anchor 10 Section restoration panel 11 Reinforced concrete structures 12 Removal Department 13 Formwork 14 Injection material 15 Rebar 16 injection holes

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[Procedure amendment]

[Submission date] July 15, 2002 (2002.7.1)
5)

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0040

[Correction method] Change

[Correction content]

[0040]

As described above, the present invention has the following effects.

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Claims (5)

[Claims] 1. Deterioration of a reinforced concrete structure characterized in that a groove is formed on one surface of a panel plate at an appropriate interval, and an electrode for anticorrosion is fixed to the groove by projecting from the groove to the surface. Preventive cross-section restoration panel. 2. The cross-section restoration panel for preventing deterioration of a reinforced concrete structure according to claim 1, wherein the panel slab is a mortar slab containing cement as a main component. 3. A reinforced concrete structure from which damaged portions have been removed, and grooves are formed on one side of a panel plate at appropriate intervals,
A cross-section restoration panel, in which an electrode for electrocorrosion is projected and fixed on the groove from the groove, is provided with a constant interval, and the electrode-fixing surface for cathodic protection faces the structure. The method for preventing deterioration of a reinforced concrete structure, comprising: injecting an injecting material between the structure and the cross-section restoration panel to restore the cross-section, and energizing the electrode for electrical protection after cross-section restoration. 4. The method for preventing deterioration of a reinforced concrete structure according to claim 3, wherein the panel plate is a mortar plate containing cement as a main component. 5. The method for preventing deterioration of a reinforced concrete structure according to claim 3, wherein the injection material is cement mortar mixed with a conductive material.