JP2014194046A - Electric anticorrosion method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electric anticorrosion method which allows easy check of the condition of a connection between an electrification terminal and a conductor wire and repair.SOLUTION: An electric anticorrosion method is provided with an electrification terminal which is arranged on the surface of a structure embedded with a metal material and is connected electrically to the metal material within the structure through a conductor wire and an anode layer which covers at least a part of the electrification terminal and the surface of the side of the structure where the electrification terminal is arranged. The electrification terminal includes a terminal body covered at least partially by the anode layer and a terminal exposure part exposed from the anode layer, and the conductor wire is connected to the terminal exposure part.

Description

  The present invention relates to an anticorrosion method comprising an anode layer for anticorrosion formed on the surface of a structure in which a metal material is embedded.

  A steel material embedded in a structure made of concrete or the like is originally protected from corrosion because a passive film is formed on the surface. However, in environments where there is a large amount of chlorine components, such as coastal areas and areas where anti-freezing agents are frequently used, the chlorine components penetrate into the structure and partially pass the passive film on the steel surface. May be destroyed. And since a ferrous ion elutes from the part by which the passive film was destroyed, steel materials will corrode (oxidize). Thereby, a crack may arise in a structure when the volume of a corrosion part expands.

  As described above, when partial corrosion occurs in the steel material, a corroded region (anode portion) and a non-corroded region (cathode portion) are formed in the steel material. There is a potential difference between the anode part and the cathode part. Electrons flow from the anode part to the cathode part to generate a corrosion current, further elution (corrosion) of iron ions from the anode part. It becomes a factor to make progress.

  As a method for preventing the progress of such corrosion, an anti-corrosion method in which an anode layer composed of a metal having a higher ionization tendency than iron in the steel material is provided on the surface of the structure and electrically connected to the steel material in the structure. The construction method is known. For example, a current-carrying terminal that is electrically connected to a steel material in a structure via a conductor is installed on the surface of the structure, and a metal that serves as an anode is sprayed onto the surface of the structure so as to cover the surface of the structure and the current-carrying terminal. A method of forming an anode layer is known (see Patent Document 1). In such a construction method, since the anode layer corrodes before the steel material, it is possible to prevent a corrosion current from being generated in the steel material in the structure. For this reason, it is possible to prevent the corrosion of the steel material from being accelerated by the corrosion current.

JP 2008-156671 A

  However, in the above construction method, since the entire energizing terminal is covered with the anode layer, the connection portion between the energizing terminal and the conductive wire is covered with the anode layer. For this reason, when the connection part of an electricity supply terminal and a conducting wire is damaged, or an electrical connection state is no longer maintained, it becomes difficult to repair such a connection part.

  Then, this invention makes it a subject to provide the cathodic protection method which can confirm easily and repair the connection state of an electricity supply terminal and a conducting wire.

  The cathodic protection method according to the present invention includes an energization terminal that is installed on the surface of a structure in which a metal material is embedded and is electrically connected to the metal material in the structure via a conductor, and at least one of the energization terminals. And an anode layer that covers the surface of the structure where the current-carrying terminals are installed, and the current-carrying terminals are at least partially covered by the anode layer, and the anode A terminal exposed portion exposed from the layer, and the conductor is connected to the terminal exposed portion.

  According to such a configuration, since the conducting wire is connected to the terminal exposed portion, the connection portion between the energizing terminal and the conducting wire is exposed from the anode layer. For this reason, while being able to confirm the connection state of an electricity supply terminal and conducting wire easily, repair of such a part can be performed easily.

  Moreover, since the connection part of an electricity supply terminal and conducting wire is exposed from an anode layer, the thickness of an anode layer can be made thinner than the case where such a connection part is covered with an anode layer. Here, as the anode layer becomes thicker, cracks are more likely to occur and the anode layer is more easily peeled off from the surface of the structure. Therefore, as described above, since the connection portion between the energizing terminal and the conductive wire is exposed from the anode layer, it is possible to reduce the thickness of the anode layer, and thus it is possible to suppress the occurrence of cracks in the anode layer. The anode layer can be prevented from peeling off from the structure surface.

  The anode layer covers a base anode layer formed between the surface of the structure and the current-carrying terminal, a surface of the ground anode layer on the side where the current-carrying terminal is disposed, and covers a portion other than the terminal exposed portion of the current-carrying terminal. It is preferable that it is comprised from the covering anode layer formed in this way.

  According to such a configuration, the energization terminal is sandwiched between the covering anode layer and the base anode layer. For this reason, the adhesion between the coated anode layer and the underlying anode layer and the current-carrying terminal is improved, and the anticorrosive action can be exhibited stably.

  It is preferable that the energizing terminal includes a terminal projecting portion projecting from the terminal main body portion, and the terminal projecting portion is configured to be inserted into a recessed portion formed in a structure and to be fitted to the recessed portion.

  According to such a configuration, the energizing terminal can be fixed to the structure by fitting the terminal projecting portion with the recess formed in the structure. Thereby, the operation | work which covers an electricity supply terminal with an anode layer can be performed easily.

  It is preferable that the terminal exposed portion of the energization terminal is formed so as to protrude from the anode layer, and is electrically connected to the conductor at a position away from the anode layer.

  According to such a configuration, the terminal exposed portion protrudes from the anode layer and is electrically connected to the conductive wire at a position away from the anode layer, so that the connection portion between the terminal exposed portion and the conductive wire is separated from the structure surface. It is formed at a spaced position. Thereby, when connecting a terminal exposure part and conducting wire, or repairing a connection part, it can prevent that a worker's hand and tool interfere with a structure, and workability worsens.

  It is preferable to further include an accommodating member that accommodates at least the terminal exposed portion.

  According to such a configuration, since the terminal exposed portion is isolated from the external space by including the housing member, the connection portion between the terminal exposed portion and the conductor is influenced by the external environment (contact with rain, the sun, etc. It is possible to prevent deterioration or damage due to irradiation of light from the light source.

  As described above, according to the present invention, the connection state between the energizing terminal and the conductive wire can be easily confirmed and repaired.

The schematic sectional drawing which showed the whole structure of the cathodic protection method which concerns on 1st embodiment. The perspective view which showed the electricity supply terminal used with the cathodic protection method which concerns on the same embodiment. The schematic sectional drawing which showed the whole structure of the cathodic protection method which concerns on 2nd embodiment. (A) is the perspective view which showed the energization terminal used with the cathodic protection method which concerns on other embodiment, (b) is the perspective view which showed the energization terminal used with the cathodic protection method which concerns on another embodiment. . (A) is the schematic sectional drawing which showed the vicinity of the energization terminal of the cathodic protection method which concerns on other embodiment, (b) showed the energization terminal used with the cathodic protection method which concerns on another embodiment. Side view.

  Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. 1 and 2. In the following drawings, the same or corresponding parts are denoted by the same reference numerals, and description thereof will not be repeated.

  As shown in FIG. 1, the cathodic protection method according to the present embodiment (hereinafter also referred to as the first cathodic protection method) is in a structure X (for example, a material in which concrete, cement, or the like is kneaded with water and hardened) X. This prevents corrosion (rusting) of the metal material A (for example, steel material) A to be buried. Specifically, the first cathodic protection method is configured by electrically connecting the anode layer Y formed on the surface of the structure X and the metal material A in the structure X. More specifically, the first cathodic protection method includes a current-carrying terminal C that is installed on the surface of the structure X and is in contact with the anode layer Y, and the current-carrying terminal C is electrically connected to the metal material A via the conductor B. It is composed by being done. That is, the first cathodic protection method is configured by electrically connecting the anode layer Y and the metal material A via the energizing terminal C and the conducting wire B.

  The energizing terminal C is at least partially covered with the anode layer Y. Specifically, the energizing terminal C includes a terminal body C1 that is at least partially covered by the anode layer Y and a terminal exposed portion C2 that is exposed from the anode layer Y, and the conductor B is connected to the terminal exposed portion C2. Configured to be. The energizing terminal C includes a fixing means C3 that fixes the lead wire B to the terminal exposed portion C2. The terminal body C1 is disposed inside the anode layer Y (specifically, between a base anode layer Y1 and a covered anode layer Y2 described later). On the other hand, the terminal exposed portion C2 is formed so as to protrude from the anode layer Y (specifically, a coated anode layer Y2 described later).

  Here, the energizing terminal C will be described. As shown in FIG. 2, the energizing terminal C is composed of a plate-like member. The plate-like terminal body C1 and the plate-like terminal exposed portion C2 are arranged so as to intersect (specifically, orthogonally) to form the energization terminal C. The length of the terminal body C1 (the length in the direction in which the terminal body C1 extends from the terminal exposed part C2) L1 of the energizing terminal C is longer than the length of the terminal exposed part C2 (terminal exposed from the terminal body C1). It is formed to be longer than the length L2 in the direction in which the portion C2 extends.

  Further, the fixing means C3 for fixing the conducting wire B is configured to fix the conducting wire B at a position away from the structure X. Specifically, the fixing means C3 includes a fixing hole C3a formed at an end of the terminal exposed portion C2 on the side away from the terminal body C1, a bolt member C3b that can be inserted into the fixing hole C3a, and the bolt. A nut member C3c that can be screwed into the member C3b. Then, the bolt exposed member C3b is inserted into the fixing hole C3a from one surface side of the terminal exposed portion C2, and the nut member C3c is screwed into the bolt member C3b from the other surface side of the terminal exposed portion C2, so that the terminal exposed portion. The end portion of the conducting wire B is sandwiched between C2 and the end portion of the bolt member C3b.

  Returning to FIG. 1, the anode layer Y includes a base anode layer Y <b> 1 formed between the surface of the structure X and the current-carrying terminal C, a surface on the side where the current-carrying terminal C is disposed in the ground anode layer Y <b> 1, and current flow. It is comprised from covering anode layer Y2 formed so that terminal exposure part C2 of terminal C may be covered (specifically, terminal main-body part C1). The thickness of the base anode layer Y1 and the covering anode layer Y2 is preferably 50 μm or more and 300 μm or less. Specifically, the thickness of the base anode layer Y1 is preferably 50 μm or more and 150 μm or less. On the other hand, the thickness of the coated anode layer Y2 is preferably 100 μm or more and 200 μm or less.

  Examples of the method for forming the base anode layer Y1 and the coated anode layer Y2 include a method in which a metal component constituting the anode layer Y is sprayed on the surface of the structure X. Examples of the thermal spraying method include a gas spraying method, a gas spraying method, an arc spraying method, and a plasma spraying method, and it is preferable to use a room temperature arc spraying method. The room temperature arc type thermal spraying apparatus injects low-temperature air or inert gas at a high speed, melts the metal wire in a decompression section generated by the injected air flow, and injects the molten metal with a high-speed jet air stream. Is. As a result, the injected molten metal is rapidly supercooled and atomized, and adheres to the surface of the structure X and the underlying anode layer Y1. The film thickness that can be sprayed at one time is usually about 70 μm, and the film thickness can be increased by spraying a plurality of times.

  As the metal component constituting the anode layer Y, a metal component having a higher ionization tendency than the metal material A (specifically, a single metal, an alloy or a pseudo alloy) is used. The metal component constituting the anode layer Y is not particularly limited, and examples thereof include zinc, zinc alloy, aluminum, aluminum alloy, indium, copper, and copper alloy. A zinc alloy refers to an alloy composed mainly of Zn and containing at least one metal selected from Al, Cu, Mg, Fe, In and the like. An aluminum alloy refers to an alloy containing Al as a main component and containing at least one metal selected from Zn, Mg, Cr, Si, In, and the like. The copper alloy refers to a copper alloy containing Cu as a main component and containing at least one metal selected from Ni, Zn, Sn, Al, In and the like.

  As the metal component constituting the anode layer Y, it is preferable to use a zinc-aluminum pseudoalloy having a weight ratio of Zn: Al of 90:10 to 50:50. By using such a metal component, the anode layer Y is excellent in anticorrosive property, has a large cohesive fracture force, is dense, and does not easily generate blisters. Zinc-aluminum pseudo-alloy does not form an alloy structure between zinc and aluminum, and it appears that zinc fine particles and aluminum fine particles are irregularly overlapped to form a zinc-aluminum alloy. Say things.

  When the first cathodic protection method having the above-described configuration is performed, first, the base anode layer Y1 is formed on the surface of the structure X by spraying a metal component constituting the base anode layer Y1. Next, the energizing terminal C is disposed on the surface of the base anode layer Y1. At this time, it is preferable to fix the energizing terminal C to the base anode layer Y1 using an adhesive, an adhesive tape, or the like. And the metal component which comprises the covering anode layer Y2 is sprayed so that the surface of the base anode layer Y1 and the terminal main-body part C1 of the energization terminal C may be covered, and the covering anode layer Y2 is formed. At this time, it is preferable to cover the terminal exposed portion C2 of the energizing terminal C with a masking tape or the like to prevent the terminal exposed portion C2 from being covered with the metal component to be sprayed.

  And the edge part of the conducting wire B electrically connected to the metal material A in the structure X is fixed to the energizing terminal C (specifically, the terminal exposed part C2) using the fixing means C3. Thereby, the metal material A in the structure X and the anode layer Y (specifically, the base anode layer Y1 and the covering anode layer Y2) are electrically connected via the energizing terminal C and the conductor B. And the accommodation member D which accommodates so that at least terminal exposure part C2 (specifically, the whole electricity supply terminal C) may be installed is installed. The housing member D includes a side wall D1 formed in a cylindrical shape and a lid D2 that closes one opening of the side wall D1, and the other opening of the side wall D1 is on the structure X side. Fixed to. And the accommodation member D is comprised so that visual recognition of the connection state of the electricity supply terminal C and the conducting wire B is possible by removing the cover part D2.

  As described above, according to the cathodic protection method according to the present invention, the connection state between the energizing terminal and the conductive wire can be easily confirmed and repaired.

  That is, in the first cathodic protection method, since the lead wire B is connected to the terminal exposed portion C2, the connection portion between the energizing terminal C and the lead wire B is exposed from the anode layer Y. For this reason, while being able to confirm the connection state of the electricity supply terminal C and the conducting wire B easily, the repair of such a part can be performed easily.

  Further, since the connection portion between the energizing terminal C and the conductive wire B is exposed from the anode layer Y, the thickness of the anode layer Y can be made thinner than when such a connection portion is covered with the anode layer Y. Here, as the anode layer Y becomes thicker, cracks are more likely to occur, and the anode layer Y is more easily peeled off from the surface of the structure X. Therefore, as described above, since the connection portion between the energizing terminal C and the conductive wire B is exposed from the anode layer Y, the thickness of the anode layer Y can be reduced. It can suppress that the layer Y peels off from the structure X surface.

  In addition, since the energizing terminal C is sandwiched between the base anode layer Y1 and the coated anode layer Y2, the adhesion between the coated anode layer Y2 and the base anode layer Y1 and the energized terminal C is improved and stabilized. Anti-corrosion action.

  The terminal exposed portion C2 protrudes from the anode layer Y and is electrically connected to the conductor B at a position spaced from the anode layer Y, so that the connection portion between the terminal exposed portion C2 and the conductor B is the surface of the structure X. It is formed at a position separated from. Thereby, when connecting the terminal exposure part C2 and the conducting wire B or repairing the connection part, it is possible to prevent the operator's hand or tool from interfering with the structure X to deteriorate workability. .

  In addition, since the terminal exposed portion C2 is isolated from the external space by including the housing member D, the connection portion between the terminal exposed portion C2 and the conductor B is influenced by the external environment (from contact with rain, the sun, etc.). It is possible to prevent deterioration or damage due to irradiation of light.

<Second embodiment>
Next, a second embodiment of the present invention will be described with reference to FIG. Compared with the first cathodic protection method, the cathodic protection method according to the second embodiment (hereinafter also referred to as the second cathodic protection method) mainly differs in the configuration of the energizing terminals E. Therefore, below, it demonstrates centering on a different point from 1st embodiment, and abbreviate | omits description by attaching | subjecting the same code | symbol to the same structure.

  The energizing terminal E includes a terminal body E1 having a flat plate shape and a terminal protrusion E2 protruding from the terminal body E1. The terminal body E1 is configured such that the outer peripheral portion (specifically, the region other than the substantially central portion) is covered with the anode layer Y (specifically, the coated anode layer Y2). That is, the terminal body E1 has a region (specifically, substantially central portion) that is not covered by the anode layer Y (specifically, the coated anode layer Y2) as the anode layer Y (specifically, the coated anode layer). Y2) is exposed to be a terminal exposed portion E3.

  The terminal protruding portion E2 is configured to fit into the recess X1 formed in the structure X. Specifically, the terminal protruding portion E2 is formed by a fixing means E4 that fixes the conductive wire B to the terminal exposed portion E3 protruding from the terminal main body portion E1. The fixing means E4 includes a protruding member E5 that is inserted through a fixing hole E1a formed in the terminal body E1 and protrudes from the terminal body E1, and a bolt member E6 that is screwed into the protruding member E5.

  The protruding member E5 is disposed so as to protrude to one surface side of the terminal body E1 while being inserted through the fixing hole E1a. Thereby, the terminal protrusion E2 is formed. The terminal protrusion E2 penetrates through the base anode layer Y1 and is fitted into the recess X1 of the structure X. Then, the energizing terminal E (specifically, the terminal main body E1) is fixed to the structure X by screwing the bolt member E6 to the protruding member E5 from the surface of the terminal main body E1 in the other direction. The end portion of the conducting wire B is sandwiched between the terminal body portion E1 (specifically, the terminal exposed portion E3) and the end portion of the bolt member E6. In addition, although it does not specifically limit as a raw material which comprises the protrusion member E5, It is preferable to use the raw material which does not have electroconductivity, for example, it is preferable to use a synthetic resin.

  According to such a configuration, the terminal C E can be fixed to the structure X by fitting the terminal protrusion E2 with the recess X1 formed in the structure X. Thereby, the operation | work which covers the electricity supply terminal C with the anode layer Y can be performed easily.

  In addition, the cathodic protection method according to the present invention is not limited to the above embodiment, and various modifications can be made without departing from the gist of the present invention. Further, the configurations and methods of the plurality of embodiments described above may be arbitrarily adopted and combined (even if the configurations and methods according to one embodiment are applied to the configurations and methods according to other embodiments). Of course, it is of course possible to arbitrarily select configurations, methods, and the like according to various modifications described below and employ them in the configurations, methods, and the like according to the above-described embodiments.

  For example, in the above embodiment, the terminal main body portions C1 and E1 of the energization terminals C and E are formed in a rectangular shape, but the present invention is not limited to this, and for example, the terminal main body portion is formed in a circular shape. Also good.

  Moreover, as shown to Fig.4 (a), the energization terminal F may be comprised from the circular terminal main-body part F1, and the through-hole F1a may be formed in the center part of the terminal main-body part F1. Moreover, as shown in FIG.4 (b), the electricity supply terminal C by which the several through-hole C1a was formed in the terminal main-body part C1 may be sufficient. Thus, when the through holes C1a and F1a are formed in the terminal main body portions C1 and F1, when the coated anode layer Y2 is formed, a part of the coated anode layer Y2 enters the through holes C1a and F1a. Since it is in contact with the base anode layer Y1, the bondability between the base anode layer Y1 and the coated anode layer Y2 becomes good. Further, when the through holes C1a and F1a are not formed, air is unintentionally interposed between the terminal body portions C1 and F1 and the base anode layer Y1, and the energization terminals C and F and the base anode layer Y1 There is a possibility that the adhesion of the resin may be lowered. However, by forming the through holes C1a and F1a, it is possible to prevent air from interposing between the energization terminals C and F and the base anode layer Y1.

  Moreover, in the said embodiment, although the terminal protrusion part E2 is comprised by the fixing means E4, it is not limited to this, For example, as shown to Fig.5 (a), it supplies with electricity in the 1st cathodic protection method In the terminal C, a terminal protrusion E2 may be formed as a part different from the fixing means C3. In such a case, the region where the terminal protrusion E2 is formed may be covered with the covering anode layer Y2.

  In the first cathodic protection method, an L-shaped energizing terminal C formed so that the terminal main body C1 extends from one end of the terminal exposed portion C2 in one direction toward one surface side is used. However, the present invention is not limited to this. For example, as shown in FIG. 5B, the terminal main body C1 that extends from one end portion in one direction toward the one surface side of the terminal exposed portion C2. Further, a Z-shaped energizing terminal G formed from the other end portion in one direction in the terminal exposed portion C2 and the terminal extending portion C4 extending toward the other surface may be used. In such a case, the fixing means C3 may be configured to be attached to the terminal extension C4.

  Moreover, in the said embodiment, although the electricity supply terminals C, F, and G are connected with the conducting wire B by the fixing means C3, it is not limited to this, For example, each electricity supply terminal and the edge part of the conducting wire B have it. You may connect by welding.

  Moreover, in the said embodiment, although the anode layer Y was comprised from the base anode layer Y1 and the covering anode layer Y2, it is not limited to this, For example, without providing the base anode layer Y1, a covering anode The layer Y2 may be formed.

  A ... Metal material, B ... Conductor, C ... Current terminal, C, E, F, G ... Current terminal, C1, E1, F1 ... Terminal body, C1a, F1a ... Through hole, C2, E3 ... Terminal exposed part, C3, E4 ... fixing means, C3a, E1a ... fixing hole, C3b ... bolt member, C3c ... nut member, C4 ... terminal extension part, D ... housing member, D1 ... side wall part, D2 ... lid part, E2 ... terminal protrusion Part, E5 ... projecting member, E6 ... bolt member, X ... structure, X1 ... recess, Y ... anode layer, Y1 ... base anode layer, Y2 ... coated anode layer

Claims (5)

An energizing terminal installed on the surface of the structure in which the metal material is embedded and electrically connected to the metal material in the structure via a conductor, and an energizing terminal in the structure that covers at least a part of the energizing terminal A cathodic protection method comprising an anode layer covering the surface on the side where
The current-carrying terminal comprises a terminal main body part at least partially covered with an anode layer, and a terminal exposed part exposed from the anode layer, and the conductive wire is connected to the terminal exposed part. .   The anode layer covers a base anode layer formed between the surface of the structure and the current-carrying terminal, a surface of the ground anode layer on the side where the current-carrying terminal is disposed, and covers a portion other than the terminal exposed portion of the current-carrying terminal. The cathodic protection method according to claim 1, comprising: a coated anode layer formed as described above.   The energizing terminal includes a terminal projecting portion projecting from the terminal main body, and the terminal projecting portion is configured to be inserted into a recessed portion formed in a structure so as to be fitted to the recessed portion. The cathodic protection method according to claim 1 or 2.   The terminal exposed portion of the energization terminal is formed so as to protrude from the anode layer, and is electrically connected to the conductor at a position spaced from the anode layer. The cathodic protection method described.   The cathodic protection method according to any one of claims 1 to 4, further comprising a housing member for housing at least the terminal exposed portion.

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