JP6393601B2 - Simple repair method and simple repair structure of reinforced concrete structure without sacrificial section repair using sacrificial anode material - Google Patents

Description

  The present invention uses a sacrificial anode material for a deteriorated portion caused by corrosion of a reinforcing bar or the like of a reinforced concrete structure, and a sacrificial anode material that can prevent rebar corrosion of a concrete structure for a long period of time by simple repair without repairing a cross section. The present invention relates to a simple repair method and a simple repair structure of a reinforced concrete structure that does not involve cross-sectional repair.

  In the maintenance management of reinforced concrete structures, mainly road outer walls, bridges, tunnels, etc., corrosion of reinforcing steel in concrete due to salt damage and neutralization due to flying salt content and anti-freezing agents in coastal areas has become a problem. The exfoliation caused by the expanded rebar destroying the concrete may lead to personal injury and is a serious problem.

  For this reason, repair methods for concrete structures due to corrosion of reinforcing steel bars have been proposed, but for damaged parts where cross-sectional defects have occurred, rust preventive materials are applied and left to stand or large-scale using mortar or concrete. It is normal to perform cross-section repair work. The cross-section repair method is a method for restoring the cross-section of the concrete structure to the original cross-sectional dimension after forming the concrete removal portion and treating the corrosion of the reinforcing bars.

  However, when only the rust preventive material is used, the durability is short, corrosion of the reinforcing bar progresses, deterioration of the structure progresses, and repair costs increase as a result. In addition, it takes a lot of time and money to perform the cross-section repair work, which has a great impact on society, such as road closures.

  In addition, macrocell corrosion occurs at the boundary between the existing concrete and the new concrete or mortar in the repaired part that can be repaired by cross-section, but there is a sacrificial anode method as a method to prevent corrosion of reinforced concrete structures and repaired parts of reinforcing steel over a long period of time. .

  Some products on the market consist of a pack-type anode body covered with special mortar and a wire for rebar binding, and the mortar used in the pack material is compatible with concrete and sustains the activity of the anode. It retains the electrolyte, is embedded in the concrete of the repaired part, is connected to the reinforcing bar in a metallic manner, and at the same time, the cross-section is repaired with concrete or mortar, enabling ion exchange between the sacrificial anode material and the concrete to prevent the reinforcing bar corrosion. As a repair method that can be prevented, the cross-sectional repair structure of Patent Document 1 is known.

  Also proposed is a method of preventing corrosion of reinforcing bars by spraying metal, which has a higher ionization tendency than iron, on the concrete surface, or by installing sheet-like or panel-like anode materials and making metallic connections to the reinforcing bars inside the concrete. Has been.

  However, in the repair method described above, repairing the cross section with mortar or concrete is an essential condition of the sacrificial anode method, large equipment for metal spraying, uniform flat surface, and a certain large area. Even if it is a condition of installation, it is a large-scale repair work such as adjustment of the foundation concrete and the installation process using anchor bolts and rivets, even if a deteriorated part is investigated as part of the maintenance and a cross-sectional defect due to rebar corrosion is found It cannot be repaired easily on the spot. For this reason, investigations and repairs of defective parts are sometimes carried out by another administrator or another organization, which causes an increase in repair costs and an expansion of deteriorated parts.

Japanese Patent No. 3099830 JP 2008-291485 A JP 2009-150222 A Special Table 2002-536544 JP2011-38131A

  In view of the above-mentioned conventional drawbacks, the present invention easily extends the life of a reinforced concrete structure on the spot without maintenance by a person in charge of maintenance or inspection without performing large-scale repair such as cross-sectional repair. It is an object of the present invention to provide a simple repair method and a simple repair structure of a reinforced concrete structure that does not involve cross-sectional repair using a sacrificial anode material that can be used.

The above and other objects and novel features of the present invention will become more fully apparent when the following description is read in conjunction with the accompanying drawings.
However, the drawings are for explanation only and do not limit the technical scope of the present invention.

  In order to achieve the above object, the present invention metallicly connects a sacrificial anode material to a reinforcing bar exposed in a concrete removing portion, and also attaches the sacrificial anode material to the concrete removing portion or the existing concrete portion by an ion-exchangeable conductive material. A sacrificial anode material installation step for fixing and a cross-section repair using the sacrificial anode material without a sacrificial anode material covering step with the waterproof material so that the reinforcing bar and the sacrificial anode material are in the same environment after the sacrificial anode material installation step is not involved. It constitutes a simple repair method for reinforced concrete structures.

  Further, the present invention provides a concrete removal portion formed by removing surface concrete in a deteriorated portion due to corrosion of a reinforcing bar in a reinforced concrete structure or formed by peeling off surface concrete naturally due to corrosion of a reinforcing bar in a reinforced concrete structure, and the concrete. Reinforcing bars exposed in the removal section, a sacrificial anode material that is metallically connected to the reinforcing bars and fixed to the concrete removal section or the existing concrete section by an ion-exchangeable conductive material, and the reinforcing bars and the sacrificial anode material A simple repair structure of a reinforced concrete structure without a cross-sectional repair using a sacrificial anode material is constructed with a waterproof material that can be covered so as to be in the same environment.

As is clear from the above description, the present invention has the following effects.
(1) In the invention of claim 1, since it is not necessary to repair the concrete removal portion with mortar or the like, the cross-section is repaired as in other construction methods in which only the cross-section repair is performed or the sacrificial anode material is embedded to perform the cross-section repair. Since it is not necessary to make many roads and roads for restoration, it is possible to obtain a simple and sufficient rebar corrosion inhibition effect without requiring much time and cost.
(2) Since the person in charge who conducts maintenance and investigation can perform repairs within the scope of the activity, the performance of the concrete structure can be easily maintained.
(3) Significant reduction in materials used, without the need for large-scale repairs, easily and simply using reinforced concrete structures on the spot, without the use of heavy machinery and special construction equipment, and transporting many materials, Environmentally friendly repairs such as waste reduction can be performed, and the performance of concrete structures can be easily maintained without labor and costs such as blocking roads.
(4) In the invention of claim 2 as well, the same effects as in the above (1) to (3) can be obtained, and in addition, it is easy to remove a part of concern in the future, such as concrete floating, or to construct a concrete removal part. Can be formed.
(5) In the invention of claim 3 as well, the same effects as in the above (1) to (4) can be obtained, and the corroded reinforcing bar and the sacrificial anode material are not in direct contact with each other. It is possible to prevent a current from flowing.
Therefore, the entire rebar can be efficiently protected over a wide area.
(6) In the invention of claim 4, the same effects as in the above (1) to (4) can be obtained.
(7) In the invention of claim 5, the same effects as in the above (1) to (5) can be obtained.

The process drawing of the 1st form for carrying out the present invention. Explanatory drawing of the surface concrete removal process of the 1st form for implementing this invention. Explanatory drawing of the sacrificial anode material installation process of the 1st form for implementing this invention. FIG. 4 is a sectional view taken along line 4-4 of FIG. The outline explanatory view of the sacrificial anode material of the 1st form for carrying out the present invention. Explanatory drawing of the simple waterproofing process of the 1st form for implementing this invention. Explanatory drawing which shows the simple repair structure of the 1st form for implementing this invention. Process drawing of the 2nd form for implementing this invention. Explanatory drawing of the sacrificial anode material installation process of the 2nd form for implementing this invention. FIG. 10 is a sectional view taken along line 10-10 in FIG. 9; Explanatory drawing which shows the simple repair structure of the 2nd form for implementing this invention. Process drawing of the 3rd form for implementing this invention. Explanatory drawing of the surface layer concrete of the 3rd form for implementing this invention. Explanatory drawing which shows the simple repair structure of the 3rd form for implementing invention.

  Hereinafter, the present invention will be described in detail with reference to the embodiments shown in the drawings.

  In the first embodiment for carrying out the present invention shown in FIG. 1 to FIG. 7, 1 is a maintenance person or an inspector who can easily perform on-site without carrying out large-scale repair such as cross-sectional repair. This is a simple repair method for reinforced concrete structures without sacrificial cross-section repair using a sacrificial anode material that can prolong the life of the reinforced concrete structure 2 in a simple manner. The repair method 1 is a surface concrete removal step 7 for removing the surface concrete 5 of the deteriorated portion 4 such as cracks, floats, and peeling caused by corrosion of the reinforcing bars 3 of the reinforced concrete structure 2 to form a concrete removal portion 6; A pack-type sacrificial anode material 8 covered with special mortar is metallically connected to the reinforcing bar 3 exposed to the concrete removal portion 6 with an iron wire or a conductive wire 9. In addition, the sacrificial anode material installation step 11 in which the sacrificial anode material 8 is installed and fixed to the concrete removing portion 6 by the ion-exchangeable conductive material 10 and the sacrificial anode material 8 so that the rebar 3 and the sacrificial anode material 8 are in the same environment. After the anode material installation step 11, the concrete removal portion 6 is constituted by a waterproofing step 13 that covers the waterproofing material 12.

  Further, by using the simplified repair method 1 for a reinforced concrete structure without cross-sectional repair using the sacrificial anode material, a deteriorated portion 4 such as a crack, a float or a peeling caused in the concrete due to the corrosion of the reinforcing bar 3 of the reinforced concrete structure 2 The concrete removal portion 6 formed by removing the surface concrete 5 of the above, the rebar 3 exposed to the concrete removal portion 6, and the metal reinforcement connected to the rebar 3 by an iron wire or a conductive wire 9 and capable of ion exchange A reinforced concrete structure without a cross-sectional repair using the sacrificial anode material is composed of a pack-type sacrificial anode material 8 installed and fixed to the concrete removing portion 6 with a conductive material 10 and a waterproof material 12 covering the concrete removing portion 6. A simple repair structure 14 is configured.

The surface concrete removing step 7 is performed by removing the surface concrete 5 of the deteriorated portion 4 generated in the concrete due to the corrosion of the reinforcing bars 3 of the reinforced concrete structure 2 with a hand-held tool such as a hammer to expose the corroded reinforcing bars 3. This is a step of forming the removal portion 6.
In addition, when there is a factor that should be removed in advance, such as floating or peeling, on the surface concrete of the rebar deterioration part, the surface concrete removal process is performed to form the concrete removal part, but this is not an essential process of the present invention, and the rebar deterioration part If some of the reinforcing bars are exposed due to the natural peeling of the surface concrete, or if only the surface concrete removal process has already been performed, the exposed part will be the concrete removal part, and the surface concrete removal process will not be performed. Also good.

  In the sacrificial anode material installation step 11, a pack-type sacrificial anode material 8 is metallically connected to the reinforcing bar 3 by an iron wire or a conductive wire 9, and the sacrificial anode material 8 is attached to the concrete removing portion 6 by an ion-exchangeable conductive material 10. This is a process for allowing an anticorrosive current to flow from the sacrificial anode material 8 to the reinforcing bar 3 through the ion-exchangeable conductive material 10 and concrete by fixing the installation.

  As shown in FIG. 5, the pack-type sacrificial anode material 8 of the present embodiment includes an anode core 15, an iron wire or conductive wire 9 embedded or connected to the anode core 15, an electrolyte covering the anode core 15, and an oxidation It is composed of a special mortar containing a stabilizer 16 (activator). This special mortar also has an effect of absorbing expansion when the metal used for the anode core 15 corrodes.

  The anode core 15 is preferably zinc, a zinc alloy, or the like, but a metal material having a higher ionization tendency than a reinforcing bar can be used under normal conditions such as aluminum, aluminum alloy, cadmium, cadmium alloy, magnesium, and magnesium alloy.

  The oxidation stabilizer 16 is used to prevent the anode core 15 from being passivated. When the anode core is zinc, the oxidation stabilizer 16 has a pH of 13.3 or more, preferably a pH of 13.5 to more than 14. Sodium hydroxide, potassium hydroxide, lithium hydroxide or the like is used. A halogen compound such as chloride or bromide such as sodium chloride may be used.

  The ion-exchangeable conductive material 10 capable of ion exchange is a gel-like conductive sheet so that the pack-type sacrificial anode material 8 and the concrete surface 6a of the concrete removing portion 6 can be easily bonded. Although it is preferable to use a conductive gel, it can be fixed by using an epoxy resin or the like together.

  When making a metallic connection between the sacrificial anode material 8 and the reinforcing bar 3, an iron wire or a conductive wire 9 is directly bound to the reinforcing bar 3. Usually, an iron wire or a conductive wire 9 is wound around the reinforcing bar 3, but mechanical connection using soldering, welding, or other clips is also possible.

  The location of the sacrificial anode material 8 is preferably the concrete surface 6a near the reinforcing bar rather than on the reinforcing bar. This is to prevent the anticorrosion current generated in the sacrificial anode material 8 from flowing directly only to the adjacent reinforcing bars 3.

  The waterproofing step 13 covers the repaired portion including the sacrificial anode material 8 and the concrete surface 6a of the concrete removing portion 6 with the ion exchangeable conductive material 10 and the reinforcing bars 3 and the sacrificial anode material 8 installed with the waterproof material 12. As a result, the reinforcing bar 3 and the sacrificial anode material 8 are placed in the same environment, that is, in an environment in which the exchange of the concrete and ions can be performed through the conductive material without being affected by the outside air. Corrosion-proof current flows stably from the steel to the reinforcing bar 3, and corrosion of the reinforcing bar and macrocell in the rust-proof range of the repaired part and the sacrificial anode material 8 can be suppressed.

  The waterproofing material 12 used in the waterproofing step 13 can be any material that has waterproof properties such as acrylic, polyurethane, epoxy, polyurea resin, but is a material that cures quickly for the purpose of simple repair in conjunction with maintenance. Is preferred. If the rebar 3 and the sacrificial anode material 8 can be held in the same environment, the liquid waterproofing material 12 may be applied with a brush, roller, spray, etc. and cured to cover the concrete removing portion 5 in a film form. What is necessary is just to have elasticity.

  Further, if the waterproof material 12 is transparent, the repaired portion can be visually inspected, and maintenance can be further facilitated. In addition, it is suitable for the waterproof material used to consider a weather resistance according to a design life.

[Different forms for carrying out the invention]
Next, different modes for carrying out the present invention shown in FIGS. 8 to 13 will be described. In the description of the different embodiments for carrying out the present invention, the same components as those in the first embodiment for carrying out the present invention are denoted by the same reference numerals, and redundant description is omitted.

  The second embodiment for carrying out the present invention shown in FIGS. 8 to 11 is mainly different from the first embodiment for carrying out the present invention in that the reinforcing bar 3 corrodes the pack-type sacrificial anode material 8. A simple method for repairing reinforced concrete 1A and a sacrificial anode material without cross-sectional repair using such a sacrificial anode material in that it is a sacrificial anode material installation step 11A that is directly fixed via a conductive material 10 that can be ion-exchanged. The same effect as that of the first embodiment for carrying out the present invention can be obtained also as the simple repair structure 14A for reinforced concrete that does not involve cross-section repair. When the sacrificial anode material 8 is installed in this way, the sacrificial anode material 8 itself contacts the rebar 3 via the ion-exchangeable conductive material 10, so the effect of the sacrificial anode is concentrated in a limited range. can do.

  The third embodiment for carrying out the present invention shown in FIGS. 12 and 13 is mainly different from the first embodiment for carrying out the present invention in that the surface layer is naturally formed by the corrosion of the reinforcing bars of the reinforced concrete structure. The part from which the concrete is peeled off is designated as a concrete removal part 6A, and the simple method of repairing reinforced concrete 1B and the sacrificial anode material without using the repair of the cross section using such a sacrificial anode material is used in that the surface concrete removal process is not performed. The same effect as the first embodiment for carrying out the present invention can also be obtained as the simple repair structure 14B of reinforced concrete without cross-sectional repair.

  In the embodiment of the present invention, an ion-exchangeable conductive material that can be easily used in the field such as a gel-like conductive sheet, a conductive gel, and an epoxy resin is assumed. In principle, mortar that requires work is excluded, but it can be carried for a certain period of time, such as premixed mortar that can be easily kneaded by adding water in small portions and mortar filled in a caulking gun, and on site. Any mortar or cement-based material that can be easily used may be used as the conductive material of the present invention. Moreover, when the said mortar and cement-type material have sufficient waterproofness, it can be used also as a waterproofing material.

  However, care must be taken because ion exchange may be hindered depending on the electrical resistance value of the cementitious material used and the type of polymer. Generally, a cement-based material having an electric resistance value of 15000 Ω · cm or less is used, and when a polymer is used, a conformance test is performed in advance. In addition, even if it is a case where an electrical resistance value is 15000 ohm * cm or more, it can be used, but there exists an influence which a rust prevention range becomes small.

  Further, in the embodiment of the present invention, a pack-type sacrificial anode material 8 is installed and fixed to the concrete removing portion 6, and the concrete removing portion is covered with the waterproof material 12 so that the reinforcing bar 3 and the sacrificial anode material 8 are in the same environment. 6 has been described, the same rust-preventing effect can be expected by using a metal capable of obtaining a sacrificial anode effect even if it is not a pack-type sacrificial anode material, and the rebar 3 and the sacrificial anode material 8 can be expected. If it becomes the same environment, the concrete removal part 6 whole does not need to be covered with the waterproofing material 12.

  Further, the sacrificial anode material 8 is installed and fixed on the surface concrete 5 instead of the concrete removing portion 6, and the surface layer concrete 5 on which the concrete removing portion 6 and the sacrificial anode material 8 are installed and fixed is covered with the waterproof material 12, thereby sacrificing anode material 8. Since the rebar 3 is in the same environment, such a configuration may be used.

  The present invention is used in industries that inspect and repair reinforced concrete structures.

1, 1A, 1B: Simplified repair method for reinforced concrete structures without sacrificial section repair using sacrificial anode material,
2: Reinforced concrete structure, 3: Reinforcing bar,
4: Deterioration part, 5: Surface concrete,
6, 6A: Concrete removal part, 7: Surface concrete removal process,
8: Sacrificial anode material, 9: Conductive wire,
10: Conductive material 11, 11A: Sacrificial anode material installation step,
12: waterproof material, 13: waterproofing process,
14, 14A, 14B: Simplified repair structure of reinforced concrete structure without cross-sectional repair using sacrificial anode material,
15: Anode core, 16: Oxidation stabilizer.

Claims (5)

A sacrificial anode material installation step of metallicly connecting the sacrificial anode material to the rebar exposed in the concrete removal portion, and installing and fixing the sacrificial anode material to the concrete removal portion or the existing concrete portion by an ion-exchangeable conductive material; A reinforced concrete structure without sacrificial cross-section using a sacrificial anode material, comprising: a waterproofing step of covering the reinforcing bar and the sacrificial anode material with a waterproof material so that the sacrificial anode material and sacrificial anode material are in the same environment after the sacrificial anode material installation step Simple repair method. The surface concrete in the deteriorated part due to corrosion of the reinforcing steel in the reinforced concrete structure is removed, and the surface concrete removal process to form the concrete removed part, and the sacrificial anode material is metallically connected to the reinforcing bar exposed in the concrete removed part, and the ion The sacrificial anode material installation process in which the sacrificial anode material is installed and fixed to the concrete removal part or the existing concrete part with a replaceable conductive material, and the reinforcing bar and the sacrificial anode material are in the same environment after the sacrificial anode material installation process. A simple repair method for a reinforced concrete structure without a cross-section repair using a sacrificial anode material, characterized by comprising a waterproofing process covered with a waterproofing material. The sacrificial anode material installation step is characterized in that the sacrificial anode material is fixed to the concrete removal portion in the vicinity of the reinforcing bar by a conductive material capable of ion exchange so that the sacrificial anode material does not directly contact the reinforcing bar. Item 3. A simple repair method for a reinforced concrete structure using a sacrificial anode material according to item 1 or 2 without cross-sectional repair. A concrete removal part formed by removing surface concrete in a deteriorated part of a reinforced concrete structure due to corrosion of a reinforcing bar, or formed by peeling off surface concrete naturally due to corrosion of a reinforcing bar in a reinforced concrete structure, and exposed to the concrete removal part A rebar, and a sacrificial anode material that is metallically connected to the rebar and that is installed and fixed to the concrete removal portion or the existing concrete portion by an ion-exchangeable conductive material, and the rebar and the sacrificial anode material are in the same environment. A simple repair structure of a reinforced concrete structure without a cross-sectional repair using a sacrificial anode material characterized by comprising a waterproof material that can be covered as is.   5. The sacrificial anode material is installed and fixed by an ion-exchangeable conductive material at a concrete removal portion in the vicinity of the reinforcing bar so as not to directly contact the reinforcing bar exposed at the concrete removing portion. Simplified repair structure for reinforced concrete structures without sacrificial cross-section using sacrificial anode material.

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