JP5603696B2 - Inspection and confirmation method of construction of silicate surface impregnated concrete protective material and inspection device used therefor - Google Patents

Description

  The present invention relates to a concrete reforming technique, and more specifically, whether or not the construction of a concrete protective material (also referred to as a concrete reforming material) to be constructed in order to improve the durability of a concrete structure is properly performed. The present invention relates to a method and an apparatus for inspecting and confirming using a general means.

  Concrete has a high compressive strength, can support a large load, can be shaped arbitrarily, has excellent fire resistance, heat resistance, durability, etc., and is relatively inexpensive. It is used in various fields such as civil engineering and buildings.

  However, in concrete, fine voids are generated in the process of curing after placement, and cracks are generated in the concrete due to various factors such as deterioration. The concrete frame has a large number of these pores and voids, and such pores and cracks continue from the surface of the concrete block to another surface as continuous voids. That is, as shown in FIG. 7, the gap 4 generated in the concrete 2 is connected.

  Accordingly, acid rain, chlorine, and the like gradually enter the concrete 2 through the gaps 4, and the concrete 2 is deteriorated by neutralization, salt damage, freeze-thawing, alkali aggregate reaction, and the like. Corrosion of rebars will be caused, resulting in reduced durability and poor appearance.

  For this reason, it is necessary to protect and modify the concrete itself by waterproofing the concrete 2 or applying an effective protective material to the concrete surface or infiltrating the concrete.

  As a prior example of a protective material such as a silicate-based surface-impregnated concrete protective material used for the purpose of protecting and improving the durability of concrete, for example, there is one described in Japanese Patent No. 2937309. This prior-art modifier is applied or infiltrated with an inorganic permeable protective material mainly composed of sodium silicate at the protective site or repair site, and after drying, the water is sprayed several times to put the protective material in the concrete. It is impregnated to form a protective layer.

  Moreover, the permeable concrete modifier described in Japanese Patent No. 4472266 (Japanese Patent Laid-Open No. 2004-323333) is formed by mixing at least two kinds of alkali metal compounds. That is, it is a concrete protective material in which at least two or more kinds of alkali metal compounds selected from sodium silicate, potassium silicate and lithium silicate are mixed as an alkali metal compound.

  When these protective materials are applied or spread on the surface of a concrete structure, they penetrate into the concrete and react with calcium hydroxide, calcium carbonate, calcium hydrogen carbonate, etc., which are concrete components, to form inorganic crystals. This plugs the continuous pores in the concrete, prevents harmful substances such as acid rain, salinity, and carbon dioxide from entering and diffusing into the concrete, thereby suppressing deterioration of the concrete.

Japanese Patent No. 2937309 JP 2004-323333 A

  However, since the silicate surface impregnated concrete protective material is a colorless and transparent liquid and penetrates into the concrete at the construction site, it is visually determined whether or not the silicate surface impregnated concrete protective material has been constructed. It was difficult to confirm. That is, there is no method for inspecting and confirming whether or not it has been reliably applied, and there is a problem that it is difficult to confirm that the silicate-based surface-impregnated concrete protective material has been constructed and to manage the construction. In addition, there is a problem that it is difficult to prove that the silicate-based surface-impregnated concrete protective material is properly applied to the orderer, the client, and the like.

  The present invention has been proposed in view of the above, and its object is to easily, reliably and objectively construct a silicate surface impregnated concrete protective material on a concrete frame using electrical means. It is to provide a method and apparatus that can be inspected and confirmed.

In the first aspect of the present invention, after a silicate-based surface-impregnated concrete protective material is applied to a concrete frame, a voltage is applied to the concrete of the concrete frame to measure a volume resistivity after the operation, Inspecting and confirming that the silicate-based surface-impregnated concrete protective material has been constructed based on the rate, this is a method for inspecting and confirming the construction of the silicate-based surface-impregnated concrete protective material.
The invention of claim 2 is the method of inspection and confirmation of construction of the silicate surface impregnated concrete protective material according to claim 1, wherein the measurement of the volume resistivity after construction is the protection of the silicate surface impregnated concrete. A pair of current electrodes connected to the voltage applying means and a pair of potential difference electrodes positioned between the current electrodes are provided at appropriate positions of the concrete frame where the material is applied, and the pair of current electrodes are interposed through the pair of current electrodes. A voltage is applied to the concrete, the current is measured with an ammeter inserted between the pair of current electrodes, the potential difference is measured with a potential difference measuring means connected to the pair of potential difference electrodes, and the obtained current and potential difference are measured. This is a method for inspecting and confirming the construction of a silicate-based surface-impregnated concrete protective material, wherein the post-construction volume resistivity is calculated using a value.
A third aspect of the present invention is the inspection and confirmation method for the construction of the silicate surface impregnated concrete protective material according to the second aspect, wherein the pair of current electrodes and the pair of potential difference electrodes are provided on the concrete surface of the concrete frame. This is a method for inspecting and confirming the construction of a silicate-based surface-impregnated concrete protective material.
According to a fourth aspect of the present invention, in the inspection and confirmation method for the construction of the silicate-based surface-impregnated concrete protective material according to the second aspect, each portion of the concrete frame where the pair of current electrodes is installed has a predetermined depth. A method for inspecting and confirming the construction of a silicate-based surface-impregnated concrete protective material, characterized in that the holes are drilled and each of the pair of current electrodes is inserted and installed in the obtained holes, and the inspection is performed. .
The invention according to claim 5 is the method of inspection and confirmation of construction of the silicate surface impregnated concrete protective material according to claim 2, wherein the concrete is located between the pair of current electrodes. This is an inspection and confirmation method for the construction of the system surface impregnated concrete protective material.
The invention of claim 6 is the method for inspecting and confirming the construction of the silicate surface impregnated concrete protective material according to any one of claims 1 to 4, before the construction of the silicate surface impregnated concrete protective material. In addition, the volume resistivity before construction is measured in the same manner as that performed after the construction, and the volume resistivity after construction and the volume resistivity before construction are compared, and the silicate surface impregnated concrete This is a method for inspecting and confirming the construction of a silicate-based surface-impregnated concrete protective material characterized by inspecting and confirming that the protective material has been constructed.
The invention of claim 7 is characterized in that the voltage to be applied is a DC voltage or an AC voltage, and inspection of construction of the silicate surface impregnated concrete protective material according to any one of claims 1 to 6, This is a confirmation method.
The invention of claim 8 is an inspection apparatus for silicate surface impregnated concrete protective material construction for inspecting whether or not a silicate surface impregnated concrete protective material is applied to concrete, and applies a voltage for inspection. Power supply means, a first current electrode connected to one end of the power supply means and detachable from the concrete, and a second current electrode connected to the other end of the power supply means and also detachable from the concrete. An electrode and detachable with respect to the concrete, and connected between the first and second potential difference electrodes disposed inside the first and second current electrodes, and the first and second potential difference electrodes And a potential difference measuring means for measuring a potential difference of a surface layer portion of the concrete to which the voltage is applied via the power source means and the first and second current electrodes. An inspection apparatus for impregnating concrete protective material construction.
The invention of claim 9 is the inspection apparatus for construction of silicate surface impregnated concrete protective material according to claim 8, wherein the first and second current electrodes and the first and second potential difference electrodes are the concrete. It is provided on the surface of the silicate-based surface impregnated concrete protective material construction inspection device.
The invention of claim 10 is the inspection apparatus for construction of silicate surface impregnated concrete protective material according to claim 8, wherein the concrete is located between the first and second current electrodes, and the first and second The second potential difference electrode is provided on the surface of the concrete, and is an inspection device for silicate surface impregnated concrete protective material construction.
The invention of claim 11 is the inspection apparatus for construction of silicate-based surface-impregnated concrete protective material according to claim 8, wherein the voltage applied by the power supply means is an AC voltage or a DC voltage. .

  According to the present invention, it is possible to very easily, surely and objectively inspect, confirm and prove that a silicate surface-impregnated concrete protective material has been applied to a concrete structure. It also facilitates the management of the construction of the silicate surface impregnated concrete protective material.

  Moreover, according to invention of Claim 3, 5 and 9, the said test | inspection can be easily performed at a construction site without a destruction.

It is a figure explaining the structure and circuit of an apparatus which measure the volume resistivity of concrete of Example 1 of this invention. It is a figure explaining the inspection and confirmation method of construction of the silicate system surface impregnation concrete protective material by this invention. It is a bar graph which shows the result of having actually measured volume resistivity using the method and apparatus of this invention. It is a figure explaining the structure and circuit of the apparatus which measure the volume resistivity of concrete of Example 2 of this invention. It is a figure explaining the structure and circuit of the apparatus which measure the volume resistivity of concrete of Example 3 of this invention. It is a figure explaining the structure and circuit of the apparatus which measure the volume resistivity of concrete of Example 4 of this invention. It is a section explanatory view showing the state where pores and voids exist in concrete.

  Hereinafter, a method and apparatus for inspection and confirmation of construction of a silicate surface impregnated concrete protective material according to the present invention will be described with reference to the accompanying drawings.

  FIG. 1 is an explanatory diagram showing a state in which measurement is performed using an apparatus for measuring the volume resistivity of concrete in Example 1 of the present invention.

  In FIG. 1, 1 a is the concrete surface of the concrete frame 1. As shown in FIG. 7, the concrete housing 1 has continuous pores and voids. Therefore, as described above, harmful substances enter the interior, thereby degrading the concrete itself or corroding the internal reinforcing bars, leading to a decrease in the strength of the concrete structure.

  Outer four electrodes 4a among four electrodes arranged at equal intervals in FIG. 1 are current electrodes for applying a voltage to the concrete in order to measure volume resistivity. The current electrode 4a is a rod-shaped electrode made of a conductor such as stainless steel, titanium, copper, or platinum, and a contact portion with the concrete surface is preferably formed in a spherical shape or a needle shape. Further, an AC constant voltage power supply 8, an energization switch 12, and an ammeter 16 are inserted and connected in series between the pair of current electrodes 4a and 4a.

  In addition, two inner electrodes 6 of the four electrodes in the figure are potential difference electrodes for measuring a potential difference in order to obtain volume resistivity. This potential difference electrode 6 is a rod-like electrode made of a conductor such as stainless steel, titanium, copper, platinum or the like, like the current electrode 4 a, and its tip is preferably formed in a spherical shape or a needle shape and is connected to the potentiometer 20. Has been. The volume resistivity will be described later.

The potentiometer 20 is installed to measure the potential difference between the two potential difference electrodes 6 installed, and preferably has an input resistance of 1 × 10 ⁸ Ω or more. This is because proper measurement is difficult below that. However, it is not limited to this.

  These four electrodes 4a and 6 are installed on the concrete surface 1a, preferably at an equal interval with an interval L of about 10 to 50 mm, and substantially in a straight line. The reason why these electrodes are arranged on a substantially straight line is that the direction of the straight line connecting the tips of the potential difference electrodes and the direction of the current flowing through the concrete must be matched for accurate measurement.

  In addition, the volume resistivity from the concrete surface 1a to a shallow part is measured, so that the space | interval L between these electrodes 4a and 6 is small, and the volume resistivity from the concrete surface 1a to a deep part is measured, so that the space | interval L becomes large. . The interval L is set between about 10 to 50 mm because if it is smaller than 10 mm, only a small portion up to the surface layer portion close to the concrete surface 1a can be measured, and conversely, it is set to 50 mm or less. This is preferable because it is not necessary to make the apparatus larger than that and measure the depth of the concrete.

  The distance L between the electrodes 4a and 6 is preferably set to be larger than the maximum dimension of the aggregate contained in the concrete and smaller than about 1/3 of the cover.

  The current electrode 4a and the potential difference electrode 6 are held perpendicular to the concrete surface 1a by an electrode support member 24 preferably made of an insulating material such as vinyl chloride resin or acrylic resin. The electrode support member 24 is a member for supporting the electrodes 4a and 6 and for preventing the electrodes 4a and 6 from being short-circuited. An electrode is inserted and supported there. This is convenient for carrying around. The electrode support member 24 may not be provided.

  Also, water or gel electrolyte is impregnated between the concrete surface 1a and each electrode so that the connection between the tips of the four electrodes 4a, 6 and the concrete surface 1a is stabilized and the contact resistance is lowered. A water absorbing material 40 such as a porous material is interposed. This is because if the contact resistance of the contact portion between the electrodes 4a, 6 and the concrete surface 1a is larger than the volume resistance of concrete, accurate measurement cannot be performed. The water absorbing material 40 such as a porous material may be installed at the same time as the electrodes 4a and 6 are installed, or may be fixed to the electrodes 4a and 6 in advance.

  As an example of the gel electrolyte used here, there is one prepared by mixing tap water, sodium carboxymethylcellulose, and sodium chloride in a weight ratio of 94: 3: 3 while boiling. Further, water may be used in place of the gel electrolyte. Moreover, as a porous material used as the water absorption material 40, it is good to use sponge, gauze, etc. about 1-2 mm in thickness, for example.

  In this state, when the energizing switch 12 is turned on and an AC voltage is applied from the AC constant voltage power source 8 through the pair of electrodes 4a and the water absorbing material 40 to the concrete surface layer portion 1b of the concrete frame 1, the concrete between the current electrodes 4a. AC current flows through The applied voltage is preferably 30 V, for example. In view of the stability of the measurement result, the safety of the measurement, etc., it is desirable that the applied voltage does not exceed 30V. The AC constant voltage power source is preferably one that can continuously apply a constant AC constant voltage within a variation of ± 0.1V. The frequency is preferably in the range of 60 to 100 Hz, for example.

  In FIG. 1, a broken line indicates a current line 28 a that flows between the pair of electrodes 4 a and 4 a and flows in the concrete frame 1, and a one-dot chain line indicates an equipotential line 32.

  In this energized state, the current flowing through the concrete surface layer portion 1b is measured by an ammeter 16 connected in series with the current electrode 4a and the AC constant voltage power supply 8.

  In this energized state, the potential difference between the two potential difference electrodes 6 is measured by a potentiometer 20 connected to the potential difference electrode 6.

  Volume resistivity is the value obtained by dividing the gradient of the potential difference in the parallel direction (potential difference per unit length) by the current density and the current flowing through the inside of the object to which the voltage is applied. It is.

  The volume resistivity ρ of the concrete surface layer portion 1b is obtained by the following equation. In this equation, ρ is the volume resistivity (Ω · m), L is the distance (m) between the electrodes, V is the potential difference (V) between the pair of potential difference electrodes 6 and 6, and I is the current flowing through the concrete surface layer 1b. (A).

  Using the volume resistivity thus determined, it is inspected and confirmed whether or not the silicate-based surface-impregnated concrete protective material has been properly constructed.

  Next, the procedure for carrying out the inspection and confirmation method of the silicate surface impregnated concrete protective material construction according to the present invention will be described with reference to FIG.

  First, before construction of the silicate-based surface-impregnated concrete protective material, the volume resistivity of the concrete surface layer portion 1b before construction is measured using the above-described apparatus.

  Therefore, first, as shown in S1 of FIG. 2, the installation positions of the electrodes 4a and 6 are determined. The electrodes 4a and 6 are installed at equal intervals and in a straight line as described above, but a location without cracking or floating is selected as a measurement location. In addition, the current and voltage distribution is uneven in the vicinity of the reinforcing bars, and appropriate measurement results cannot be obtained.Check the position of the reinforcing bars using a reinforcing bar probe in advance and measure the position as far away from the reinforcing bars as possible. Select as Also, the line segments connecting the electrode positions should not overlap or intersect with the reinforcing bars.

  Next, in S2 in the figure, as a pretreatment of the measurement location, if the concrete surface 1a is contaminated with dust or oil, accurate measurement will be hindered. Therefore, before the measurement, the electrodes 4a and 6 on the concrete surface 1a are installed. Clean the area to be cleaned and remove dust and oil stains. Furthermore, since an accurate value cannot be measured even when the measurement position is extremely dry, the electrode is placed with the measurement location wet using clean water such as tap water. However, in order to affect the measurement result, excessive watering is avoided and the surface 1a is installed without floating water. That is, the electrodes 4a, 6 and the like are installed after confirming that the measurement location is in a state where it is moderately wet but water is not raised (S3).

  Between the electrodes 4a, 6 and the concrete surface 1a, as described above, a water-absorbing material 40 such as a porous material impregnated with a gel electrolyte or water is interposed, and the tips of the electrodes 4a, 6 are inserted. Are in close contact with the concrete surface 1a. Further, as described above, the AC constant voltage power supply 8, the ammeter 16, the potentiometer 20, and the like are connected.

  In this state, a voltage is applied as described above, it is confirmed that a detection value that is unstable at first is stable, and a potential difference between the potential difference electrodes 6 is measured by a potentiometer 20 connected to the potential difference electrode. At the same time, the current is measured by the ammeter 16 connected to the current electrode 4a. And the volume resistivity of the concrete surface layer part 1b is calculated using the above-mentioned numerical formula 1 (S4 in FIG. 2).

  Moreover, it is also possible to perform steel material corrosivity evaluation using the value of the obtained volume resistivity as needed. Steel corrosion evaluation using volume resistivity estimates the possibility of corrosion of steel materials such as reinforcing bars from the resistivity of concrete. The lower the resistivity, the higher the risk of steel corrosion.

  The steel material corrosive evaluation can be performed by comparing the volume resistivity value before construction with a known, for example, the following table.

  This steel material corrosion evaluation may be omitted if there is no necessity.

  Next, the measuring device is once removed, and a silicate surface-impregnated concrete protective material is applied by a known method (S5 in FIG. 2). That is, a silicate-based surface-impregnated concrete protective material is applied or sprayed on the concrete surface 1a, and then water is sprayed to permeate the protective material into the concrete surface layer portion 1b.

  Specifically, the silicate-based surface-impregnated concrete protective material to be used is preferably the one described in the aforementioned Japanese Patent No. 4472266. This protective material reacts slowly with calcium in the concrete and slowly gels, so that it penetrates deeply into the concrete.

  However, the protective material is not limited thereto, and other silicate-based surface-impregnated concrete protective materials may be used. In addition, the method for constructing the silicate-based surface-impregnated concrete protective material may be constructed by other methods as long as it is a method suitable for the protective material used.

  When the silicate-based surface-impregnated concrete protective material is properly applied, the protective material penetrates into the pores and voids of the concrete surface layer 1b, and reacts with calcium in the concrete to form a protective layer. To do. Thereby, the concrete surface layer portion 1b is densified. In addition, the code | symbol d in FIG. 1 shows the depth by which the silicate type | system | group surface impregnation concrete protective material was impregnated.

  After the construction and curing of the silicate surface impregnated concrete protective material, the volume resistivity of the concrete surface layer portion 1b is measured again using the above-described apparatus and method (S6 in FIG. 2). At this time, the voltage height, frequency, and the like applied to the concrete surface layer portion 1b are the same as those measured before construction.

  After the measurement is completed, the volume resistivity value after construction is compared with the volume resistivity value before construction (S7 in FIG. 2).

  In order to perform more accurate inspection, when measuring the volume resistivity before and after the construction of the silicate-based surface-impregnated concrete protective material, the positions of the electrodes 4a and 6 are changed little by little for each measurement. It is better to perform inspection and confirmation by measuring multiple times, calculating the volume resistivity of each, and taking the average value. Alternatively, the positions of the electrodes 4a and 6 may be changed little by little, and measurement may be performed at a plurality of positions, and the volume resistivity at each position may be compared by comparing the value before construction and the value after construction. By doing so, even if an error occurs in the measurement result due to a large aggregate or the like present at the measurement location, the influence of the error can be reduced.

  For example, in one measurement, the positions of the electrodes 4a and 6 are shifted by 1 cm, preferably at 5 to 9 points, respectively, and the average volume resistivity obtained from the measurement is taken before and after the construction. It is better to compare and check the later values, or compare the values before and after the construction at each position, respectively, for inspection and confirmation.

  If the silicate-based surface-impregnated concrete protective material is properly constructed, the volume resistivity value after construction is greater than the value before construction. This is because the concrete surface layer portion 1b is densified and it is difficult for current to flow. By densifying the concrete surface layer portion 1b, the corrosion reaction rate of the steel material in the concrete is slowed, leading to a long life of the concrete structure.

FIG. 3 shows the results of actual measurements on the highway beam columns using the method and apparatus.
In this measurement, six measurement positions were determined in one bridge, and the volume resistivity of the concrete at each measurement position was measured before and 28 days after the construction of the silicate surface impregnated concrete protective material. . Further, in order to perform more accurate determination, the measurement was performed five times by shifting the positions of the electrodes 4a and 6 by 1 cm at each measurement position.

  In the graph of Fig. 3 which is a set of two, the white bars on the left side of each group indicate the volume resistivity before construction of the silicate surface impregnated concrete protective material, and the black bars on the right side are construction. The volume resistivity measured similarly at the same position on the 28th day is shown.

  In the figure, although there are variations in numerical values between the measurement positions, the volume resistivity value after construction is larger than the volume resistivity value before construction at all positions. Thereby, it can be inspected and confirmed that the construction of the silicate surface impregnated concrete protective material has been carried out reliably. In addition, the measured value of the volume resistivity after construction differs slightly depending on the part to be measured, for example, because the state of voids in the concrete is different and the penetration state of the silicate surface impregnated concrete protective material is different.

  By measuring and comparing the volume resistivity as described above, the volume resistivity value was larger than before construction, so that the silicate surface impregnated concrete protective material was properly constructed, It can be confirmed in a non-destructive manner that the concrete has been modified.

  In addition, the volume resistivity of concrete can be obtained various values depending on the types and dimensions of aggregates and steel materials, and the measurement results may differ greatly depending on the measurement apparatus and method. Since the volume resistivity before construction and the volume resistivity after construction are measured and compared in the same method in the same concrete frame, the silicate surface is surely confirmed from the change in volume resistivity. The construction of the impregnated concrete protective material can be confirmed and inspected.

  In the volume resistivity measurement as described above, the moisture content of the concrete surface layer portion 1b affects the measurement result to some extent. Therefore, in order to inspect more accurately, the concrete surface layer portion 1b is measured by using a high-frequency moisture meter, a current-type moisture meter, etc. at the time of measuring the volume resistivity before and after the construction of the silicate surface impregnated concrete protective material. It is better to measure the moisture content of the water and match the moisture content before and after construction to some extent.

  In this process, the volume resistivity of the concrete was measured before and after the construction of the silicate-based surface-impregnated concrete protective material. In the case where the volume resistivity can be predicted when it is reliably constructed, for example, when available, the volume resistivity measurement before construction can be omitted.

  FIG. 4 is a diagram for explaining a device and a circuit for measuring volume resistivity in Example 2 of the present invention.

  The difference between Example 1 and Example 2 is obtained by drilling the concrete surface layer part 1b to a predetermined depth in Example 2 at the tip of the current electrode 4a provided on the concrete surface 1a in Example 1. The current electrode 4b is provided in a state of being inserted into the hole 36.

  In the first embodiment described above, the current line 28a of the current flowing in the concrete surface layer portion 1b has a reverse arch shape, but in this second embodiment, the current line 28b is formed between the concrete surface 1a and each potential difference electrode 6. It is almost parallel to the line connecting the two contacts, and the volume resistivity can be measured more accurately.

  In Example 1, because of the measurement method and apparatus in which the current electrode 4a is installed on the surface 1a, when the impregnation is deep, it may not be possible to measure how far the impregnation is performed.

  However, in the second embodiment, the concrete casing 1 can be measured by drilling from the surface 1a to a portion where the protective material is supposed to be impregnated and inserting the electrode 4b therethrough. It can be known from the value whether the impregnation is performed to a desired depth.

  The depth d 'of the drilling hole is desirably about 2 cm from the concrete surface 1a. However, it is not limited to this depth, and is determined in consideration of the penetration depth d of the silicate surface impregnated concrete protective material. Preferably, the depth d 'of the hole 36 is deeper than the penetration depth d of the silicate-based surface-impregnated concrete protective material. When inspecting whether or not the silicate-based surface-impregnated concrete protective material has penetrated deeply, the drilling hole may be 2 cm or more.

  A porous water-absorbing material 40 such as sponge or gauze impregnated with gel electrolyte or water is inserted into the drilled hole together with the current electrode 4b, and interposed between the peripheral wall of the hole and the current electrode 4b. Let The water absorbing material 40 may be fixed to the current electrode 4b in advance.

In the case of this embodiment, the volume resistivity can be obtained using the following equation. In this equation, ρ is the volume resistivity (Ω · m), V is the potential difference (V) between the potential difference electrodes, A is the connection area (m ² ) of one current electrode 4b with the concrete 2, and I is the concrete 2 The flowing current (A) and L are the distance (m) between the two potential difference electrodes 6.

  Since the other configuration and the inspection method of the second embodiment are the same as those of the first embodiment, the description thereof is omitted.

  FIG. 5 is a diagram for explaining an apparatus for measuring volume resistivity in Example 3 of the present invention.

  In Example 3, the bar-shaped current electrodes 4a and 4b in Example 1 and Example 2 were used as plate-shaped current electrodes 4c, and the concrete 2 was sandwiched between them. Such an electrode installation method can be implemented when the electrodes can be installed on three surfaces of the concrete 2 such as an external corridor of a building, a veranda, and an upper part of a concrete wall. Moreover, also when measuring using the test body core-collected from the concrete housing 1, it can test | inspect with the measuring method of this Example 3. FIG.

  When the current electrode 4c is installed with the concrete 2 interposed therebetween, the current electrode 4c is brought into close contact so that the contact between the holding surface and the concrete 2 is uniform. In order to stabilize the connection between the current electrode 4 c and the concrete 2, a water absorbing material 40 such as a porous material impregnated with a gel electrolyte or water is preferably interposed between the current electrode 4 c and the concrete 2. The current electrode 4c may be installed using a current electrode support (not shown) made of an insulator, for example, sandwiching the current electrode 4c, the water absorbing material 40 and the concrete 2.

  In this embodiment, two potential difference electrodes 6 supported by a potential difference electrode support material 44 made of an insulator are provided on the concrete surface 1a. The interval between the potential difference electrodes 6 is set to 1/4 to 1/2 of the interval between the two current electrodes 4c. Further, the potential difference electrode 6 has a straight line connecting the tips thereof parallel to the current flowing through the concrete 2 and the center between the two potential difference electrodes 6 coincides with the center between the two current electrodes 4c. It is desirable to install it. Also, a porous material impregnated with a gel electrolyte or water is preferably interposed between the potential difference electrode 6 and the concrete 2.

  The AC constant voltage power supply 8 and the ammeter 16 are connected to the current electrode 4c thus installed in the same manner as in the first and second embodiments. Further, the potentiometric electrode 6 installed on the concrete surface 1 a is connected to the potentiometer 20. And like Example 1, 2, a voltage is applied using the alternating current constant voltage power supply 8, a potential difference between an electric current and a potential difference electrode is measured, and volume resistivity is measured. Also in the present embodiment, the volume resistivity can be obtained by the formula [Equation 2] given in the second embodiment.

  Since the other configuration and the inspection method of the third embodiment are the same as those of the first embodiment, the description thereof is omitted.

  FIG. 6 is a diagram for explaining an apparatus for measuring volume resistivity in Example 4 of the present invention.

  The fourth embodiment uses a DC power supply 48 instead of the AC constant voltage power supply 8 of the first embodiment, applies a DC voltage to the concrete surface layer portion 1b, and measures the volume resistivity of the concrete surface layer portion 1b. is there.

  Similarly in Example 4, the construction of the silicate-based surface-impregnated concrete protective material can be inspected and confirmed by comparing the value before construction with the value after construction.

  In this case, the ammeter 52 and the potentiometer 56 are also used for DC.

  Since the other configuration and the inspection method of the fourth embodiment are the same as those of the first embodiment, the description thereof is omitted.

  Note that Example 2 and Example 3 can also be implemented using a direct current instead of an alternating current.

  In each of the above embodiments, the potential difference is measured using a potentiometer. However, a voltmeter may be used instead of the potentiometer.

DESCRIPTION OF SYMBOLS 1 Concrete frame 1a Concrete surface 1b Concrete surface layer 2 Concrete 4a, 4b, 4c Current electrode 6 Potential difference electrode 8 AC constant voltage power supply 12 Current switch 16, 52 Ammeter 20, 56 Potentiometer 24 Electrode support materials 28a, 28b, 28c Current Line 32 Equipotential line 36 Hole 40 Water absorbing material 44 Potential difference electrode support material 48 DC power supply

Claims (11)

  After constructing the silicate surface impregnated concrete protective material on the concrete frame, applying a voltage to the concrete of the concrete frame to measure the volume resistivity after the construction, from the volume resistivity after the construction, the silicate system Inspection and confirmation method of construction of silicate surface impregnated concrete protective material, characterized by inspecting and confirming that surface impregnated concrete protective material has been constructed.   In the inspection and confirmation method of the construction of the silicate surface impregnated concrete protective material according to claim 1, the measurement of the volume resistivity after the construction is performed by applying the silicate surface impregnated concrete protective material. In a suitable position of the concrete frame, a pair of current electrodes connected to the voltage application means and a pair of potential difference electrodes positioned between the current electrodes are provided, and a voltage is applied to the concrete via the pair of current electrodes, Measure the current with an ammeter inserted between the pair of current electrodes, measure the potential difference with a potential difference measuring means connected to the pair of potential difference electrodes, and use the obtained current and potential difference values after the construction A method for inspecting and confirming the construction of a silicate-based surface-impregnated concrete protective material, characterized by calculating a volume resistivity.   3. The inspection and confirmation method of construction of a silicate surface impregnated concrete protective material according to claim 2, wherein the pair of current electrodes and the pair of potential difference electrodes are provided on the concrete surface of the concrete frame. Inspection and confirmation methods for the construction of acid-based surface-impregnated concrete protective materials.   In the inspection and confirmation method for the construction of the silicate-based surface-impregnated concrete protective material according to claim 2, each portion of the concrete frame where the pair of current electrodes is installed is drilled to a predetermined depth, and obtained. A method for inspecting and confirming construction of a silicate-based surface-impregnated concrete protective material, wherein each of the pair of current electrodes is inserted into a hole and installed, and the inspection is performed.   In the inspection and confirmation method of construction of the silicate surface impregnated concrete protective material according to claim 2, the silicate surface impregnated concrete protective material is characterized in that the concrete is located between the pair of current electrodes. Construction inspection and confirmation method.   In the inspection and confirmation method for the construction of the silicate-based surface-impregnated concrete protective material according to any one of claims 1 to 4, the silicate-based surface-impregnated concrete protective material is performed before the construction and after the construction. The volume resistivity before construction was measured by the same method as above, and the volume resistivity after construction and the volume resistivity before construction were compared, and the silicate surface-impregnated concrete protective material was constructed. Inspection and confirmation of construction of silicate surface impregnated concrete protective material characterized by inspection and confirmation.   The said voltage to apply is a direct-current voltage or an alternating voltage, The inspection and confirmation method of construction of the silicate type | system | group surface impregnation concrete protective material in any one of Claims 1-6 characterized by the above-mentioned. An inspection device for silicate surface impregnated concrete protective material construction for inspecting whether or not a silicate surface impregnated concrete protective material is applied to concrete,
Power supply means for applying a voltage for inspection;
A first current electrode connected to one end of the power supply means and detachable from the concrete; a second electrode connected to the other end of the power supply means and also detachable from the concrete;
First and second potential difference electrodes that are detachable from the concrete and are arranged inside the first and second current electrodes;
A potential difference measuring means connected between the first and second potential difference electrodes and measuring a potential difference of a surface layer portion of the concrete to which the voltage is applied via the power source means and the first and second current electrodes; A silicate-based surface-impregnated concrete protective material inspection apparatus characterized by comprising.   9. The inspection apparatus for construction of a silicate surface impregnated concrete protective material according to claim 8, wherein the first and second current electrodes and the first and second potential difference electrodes are provided on the surface of the concrete. Inspection device for construction of protective material for silicate surface impregnated concrete.   9. The inspection apparatus for constructing a silicate-based surface-impregnated concrete protective material according to claim 8, wherein the concrete is positioned between the first and second current electrodes, and the first and second potential difference electrodes are the concrete. A silicate-based surface-impregnated concrete protective material construction inspection device characterized by being provided on the surface of 9. The inspection apparatus for silicate surface-impregnated concrete protective material construction according to claim 8, wherein the voltage applied by the power source means is an alternating voltage or a direct voltage.

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