JP6031274B2 - Installation method of anode material for cathodic protection - Google Patents

Description

  The present invention relates to an installation method for an anode material for cathodic protection, in which an anode material for cathodic protection is installed in a concrete structure.

  A metal material such as a reinforcing bar embedded in a concrete structure is originally protected from corrosion because a passive film is formed on the surface. However, in coastal areas and areas where anti-freezing agents are frequently used, chlorine components dissolved in moisture pass through cracks formed by deterioration of concrete structures over time and gaps in concrete structures. May penetrate into the concrete structure. In such a case, there is a possibility that the passive film of the metal material is destroyed by the intruding chlorine component, and the metal material is corroded (oxidized).

  At this time, on the surface of the corroded metal material, an oxidation reaction (anode reaction) and a reduction reaction (cathode reaction) proceed simultaneously at the corroded portion and the uncorroded portion. As a result, a potential difference is generated between the anode part and the cathode part generated on the surface of the metal material, and a corrosion current flows in the concrete structure from the anode part to the cathode part. And this corrosion current becomes a factor which further advances the corrosion of a metal material.

  As a method of preventing the progress of such corrosion, an anode material formed using a material such as titanium is installed in a concrete structure, and a current (anticorrosion current) is continuously applied between the anode material and the metal material. There has been known an anticorrosion method that eliminates a potential difference on the surface of a metal material and prevents the occurrence of a corrosion current by flowing it through the metal.

As a method of installing the anode material in an existing concrete structure, a deleted portion is formed on the surface of the concrete structure, and after the anode material is installed in the deleted portion, a filler such as mortar is filled in the deleted portion. The method of filling is done. In this case, in order to continuously flow the anticorrosion current, it is necessary to install the anode material so that the anode material and the metal material do not come into contact with each other. Therefore, the depth of the deleted portion is set so that the metal material is not exposed. Must be set.
However, it is complicated to accurately form a deletion portion having a predetermined depth so that the anode material does not come into contact with the metal material, and in particular, a small amount of work is performed near the surface of the concrete structure where the anode material is installed. When there is only space, for example, in the case of installing the anode material on the surface of the end of the bridge girder facing the gap with the adjacent bridge girder in the bridge girder laid on the pier, the work is very difficult. .

On the other hand, as a method of installing the anode material without forming the deleted portion on the surface of the concrete structure, for example, a method described in Patent Document 1 can be cited.
In Patent Document 1, concrete is obtained by attaching an anticorrosion electrode holding member to a concrete structure surface, storing an electrode (anode material) inside the holding member, and filling a filler such as cement mortar. A method for installing an anode material on a structure is described.
In such a method, since it is not necessary to form a deletion part, there is no possibility that the metal material inside the concrete structure and the anode material come into contact with each other.
However, the method of Patent Document 1 requires a space for attaching the holding member to the surface of the concrete structure, and the operation is complicated in a narrow place such as between the bridge girders.

Japanese Patent Laid-Open No. 2002-20886

  Therefore, in view of the conventional problems as described above, the present invention easily removes the surface of a concrete structure without setting an accurate depth regardless of the location, It is an object of the present invention to provide a method for installing an anode material for cathodic protection that can be easily installed on an existing concrete structure without being in contact with the material.

The method for installing the anode material for cathodic protection according to the present invention includes a deleted portion forming step of forming a deleted portion in which at least a part of the metal material is exposed by deleting the bridge girder end surface in which the metal material is installed,
After confirming the position of the metal material in the deletion portion, a filling step of filling the deletion portion with a curable filler so that the metal material is buried;
The filling unit in which the filling material is filled, and a positive electrode material placing step of placing an anode material for sacrificial so as not to contact with the metallic material.

According to the present invention, by carrying out a deleted portion forming step of forming a deleted portion such that at least a part of the metal material is exposed by deleting the surface of a concrete structure in which a metal material is installed. The deletion part for installing the anode material on the concrete structure can be formed without setting an accurate depth. Further, after confirming the position of the metal material in the deletion portion, a filling step of filling the deletion portion with a curable filler so that the metal material is buried, and a filling portion filled with the filler The anode material can be easily installed so as not to come into contact with the metal material by performing the anode material installation step of placing the anode material for cathodic protection so as not to come into contact with the metal material. Furthermore, since it is not necessary to use a holding member or the like on the surface of the concrete structure, the anode material can be installed regardless of the location. Even when the surface of the concrete structure is an end face of a bridge girder, the anode material can be easily installed according to the method for installing an anode material for cathodic protection of the present invention.

As one aspect of the present invention, before the filling step and after the deletion portion forming step, a mold frame is installed on the bridge girder end surface , and the space surrounded by the mold frame and the inner surface of the deletion portion You may further provide the mold installation process which forms.

  By performing the mold installation step, it is possible to easily fill the deletion portion so that the metal material is buried without causing the filler to flow out.

As one aspect of the present invention, a filler curing step for curing the filler may be further provided after the anode material installation step, and the mold may be left as it is after the filler curing step .

  As another embodiment of the present invention, the filler may include an elastic material.

  In the case where the filler includes an elastic material, the filler has elasticity even after the filler is cured, so that occurrence of cracks and the like at the filling portion can be suppressed.

  As another aspect of the present invention, a reinforcing material may be attached to the anode material.

  When a reinforcing material is attached to the anode material, the anode material can be easily inserted without being deformed when the anode material is inserted into the filler in the anode material installation step.

  According to the present invention, the surface of a concrete structure can be easily deleted without setting an accurate depth, and the electrode for cathodic protection is easily installed on an existing concrete structure without contacting the metal material. be able to.

(A) (b) is a schematic front view which shows the concrete structure of this embodiment. (A)-(e) is a partial cross section figure which shows the outline of the installation method of the anode material for cathodic protection of one Embodiment of this invention. The partial cross section figure which shows the outline of the anode material of this embodiment.

Hereinafter, an embodiment of a method of installing an anode material for cathodic protection according to the present invention will be described with reference to FIGS.
The installation method of the anode material for cathodic protection of this embodiment is:
A deletion part forming step of forming a deletion part such that at least a part of the metal material is exposed by deleting the surface of the concrete structure in which the metal material is installed;
After confirming the position of the metal material in the deletion portion, a filling step of filling the deletion portion with a curable filler so that the metal material is buried;
This is a method of performing an anode material installation step in which an anode material for cathodic protection is installed in a filling portion filled with the filler so as not to contact the metal material.

The concrete structure in which the cathodic protection anode is installed in the present embodiment is not particularly limited as long as it is a concrete structure in which a metal material is embedded.
In particular, in the bridge girder arranged in parallel on the bridge pier 2 as shown in FIG. 1 (a), the end face 1′a of the bridge girder 1 ′ positioned between the adjacent bridge girders 1, 1 ′, FIG. Concrete facing a narrow space such as the end face 1 ″ a of the bridge girder 1 ″ positioned between the upper surface of the bridge pier 2 ′ and the bridge girder 1 ″ as shown in FIG. When installing the anode material for cathodic protection on the surface of the structure, it is suitable to employ the method for installing the cathodic anode material of this embodiment.
This embodiment demonstrates the case where an anode material is installed in the bridge girder end surface as shown to FIG. 1 (a) (b), ie, the surface of the side surface of a concrete structure.

[Deleted part formation process]
First, as shown in FIG. 2 (a), a deletion portion forming step of forming a deletion portion 4 so that at least a part of the metal material 3 is exposed on the surface of the concrete structure 1 is performed.
The deletion unit 4 may be deep enough to expose at least a part of the metal material 3 and confirm its position. The metal material 3 is exposed without particularly setting the depth. It can be easily formed by removing the surface of the concrete structure.
Further, the size of the deletion portion 4 can be set according to the length of the anode material to be installed.
The said deletion part can form the concrete structure 1 surface using a concrete cutter, an excavation machine, etc. FIG.

[Formwork installation process]
In the present embodiment, if necessary, before the filling step and after the deletion portion forming step, a mold is installed on the concrete structure, and the inner surface of the mold and the deletion portion. You may implement the mold installation process which forms the space enclosed with.

The mold 5 is a mold made of a plate material made of wood or resin, a flexible sheet material, or the like, and can prevent the filler from flowing out when filling a filler to be described later. Any frame may be used.
The mold 5 forms a space surrounded by the mold 5 and the inner surface of the deletion unit 4. For example, as shown in FIG. 2 (b), a member 5 a disposed at a position separated from the metal material 3 is provided, and an anode material can be installed between the member 5 a and the metal material 3. It is preferable that it is a formwork which can form a space. The member 5a may be arranged outside the surface of the concrete structure 1 or may be arranged inside (in the deletion part) than the surface of the concrete structure 1.

The mold 5 is configured so that the filler does not flow out when a space described later is filled in a space surrounded by the inner surface of the deletion portion 4 and the mold 5.
Specifically, for example, as shown in FIG. 2 (b), the member 5 a is installed at a position facing the surface of the concrete structure 1, and another position corresponding to an extension line on the lower surface of the concrete structure 1 is provided. By installing the member 5b and further installing another member (not shown) at a position parallel to the side surface of the concrete structure 1 as necessary, in one direction, in this case above the concrete structure 1 With the opening remaining, the other portions can be surrounded by the inner surfaces of the mold 5 and the deletion portion 4 to form a space from which the filler does not flow out.
In addition, the installation method of the said mold 5 is not specifically limited, For example, the mold which has a predetermined shape previously may be inserted into a predetermined position from a gap | interval etc., or each separate board | plate material is each predetermined position. You may form and install a formwork by installing in.
When the plate material is installed, the size of the space may be adjusted as appropriate while fixing the plate material using, for example, a spacer for adjusting the height and width.

[Filling process]
Next, as shown in FIG. 2 (c), after confirming the installation position of the metal material 3 in the deletion unit 4, the deletion unit 4 is filled with a curable filler so that the metal material 3 is buried. Perform the filling process.

The curable filler has a certain degree of fluidity when filled, and can be used without particular limitation as long as it is a filler that hardens after insertion of the anode material, but a hydraulic material such as cement mortar should be used. Can be preferably used because of its good adhesion to concrete structures.
The cement mortar is preferably a cement-based non-shrink mortar, and examples thereof include “Filcon-R” (manufactured by Sumitomo Osaka Cement Co., Ltd.).

It is particularly preferable to use a filler containing an elastic material as the filler of this embodiment.
By including the elastic material, the filler has elasticity even after curing.
The merits of the filler having elasticity are as follows.
For example, when the position where the filler is filled is a gap between a bridge girder and a bridge girder of a bridge as shown in FIG. The width of the gap may change due to vibrations caused by traffic on the top. In this case, even if the bridge girder or the pier is vibrated and the gap width changes due to the filling with the elastic filler, the filler can follow the change in the gap width, and the filler is cracked. It is difficult to cause damage such as, and the strength reduction of the filler portion can be suppressed.

The elastic material is not particularly limited as long as it is a material that can improve the elasticity of the filler by mixing with the filler. For example, the elastic coefficient is 15 kN / mm ² or less. An elastic material or the like is preferable.
Examples of the elastic material include urethane rubber, synthetic rubber such as SBR, NBR, CR, EPM, EPDM, and FPM, natural rubber, acrylic emulsion, and a mixture of two or more thereof.
The shape of the elastic material is preferably a particulate shape from the viewpoint of mixing properties.
The mixing amount of the elastic material is preferably about 0.1 to 10.0 parts by weight with respect to 100 parts by weight of cement mortar, for example.

  As a method of filling the space with the filler, a known filling method such as a method of pouring directly from the opening of the deleted portion from a container or the like mixed with a filler, or a method of using an injector for mortar injection Can be adopted.

[Anode material installation process]
Next, an anode material installation step is performed in which an anode material for cathodic protection is installed in the filling portion 6 filled with the filler so as not to contact the metal material 3.
As the anode material for cathodic protection used in the present embodiment, for example, one formed in a strip shape, a dot shape, or a linear shape can be used, but a linear anode material is preferable from the viewpoint of easy insertion. Among the linear anode materials, it is preferable to use a mesh-like material.
The material for forming the anode material is not particularly limited, and titanium,
It can employ | adopt suitably from the materials used as general anode materials for cathodic protection, such as platinum.

When the anode material of the present embodiment has a shape that is relatively easily bent, such as the titanium mesh, a reinforcing material may be attached.
The material of the reinforcing material is not particularly limited as long as it has a strength that can prevent the anode material from being deformed, and examples thereof include metal, resin, and wood. Especially, it is preferable that it is metal from a viewpoint of high intensity | strength, and especially the metal rod, metal plate, etc. of the same material as anode materials, such as titanium, are preferable.
The method for attaching the anode material and the reinforcing material is not particularly limited. For example, as shown in FIG. 3, the anode material 7 is formed into a cylindrical body having a bottom portion, and the cylinder is formed. For example, the reinforcing member 8 such as a rod may be inserted into a space formed inside the body.
By attaching the reinforcing material 8 to the anode material 7, it is possible to prevent the anode material 7 from being deformed when inserted into the filler 6 and coming into contact with the metal material 3.

The anode material 7 is inserted into the filling portion 6 filled with the filler before the filler is completely cured. At this time, since the position of the metal material 3 is confirmed in the deletion portion forming step, it is possible to easily insert the anode material 7 at a position where the metal material 3 is not in contact.
After the anode material 7 is inserted, the filler can be hardened so that the anode material can be fixed and installed in the concrete structure 1.

  The mold 5 may be removed after the filler is cured, or may be left as it is.

  In the above-described embodiment, the method of installing the anode material on the surface of the side surface of the concrete structure such as the end face of the bridge girder has been described. Also good. Even in this case, for example, by adopting the method for installing an anode for cathodic protection according to the present invention at a position where another structure is present and difficult to work, the anode material can be easily contacted with a metal material. Can be installed.

  In addition, regarding the method of installing the anode material for cathodic protection according to this embodiment, the embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

1: Concrete structure, 3: Metal material, 4: Deletion part, 5: Formwork, 6: Filling part, 7: Anode material for cathodic protection (anode material).

Claims (5)

A deletion part forming step of forming a deletion part such that at least a part of the metal material is exposed by deleting a bridge girder end face in which a metal material is installed;
After confirming the position of the metal material in the deletion portion, a filling step of filling the deletion portion with a curable filler so that the metal material is buried;
A method of installing an anode material for cathodic protection comprising an anode material installing step of installing an anode material for cathodic protection in a filling portion filled with the filler so as not to contact the metal material. Before the filling step and after the deletion portion forming step, a mold frame is installed on the bridge girder end surface to form a space surrounded by the mold frame and the inner surface of the deletion portion. The installation method of the anode material for cathodic protection of Claim 1 further equipped with a process. After the anode material installation step, further comprising a filler curing step of curing the filler,
The installation method of the anode material for cathodic protection according to claim 2, wherein the mold is left as it is after the filler curing step.   The said filler is an installation method of the anode material for cathodic protection as described in any one of Claims 1 thru | or 3 containing an elastic material. The method for installing an anode material for cathodic protection according to any one of claims 1 to 4, wherein a reinforcing material is attached to the anode material.

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