JP4250745B2 - Seal for confirming construction of permeable inorganic concrete modifier and method for confirming construction of permeable inorganic concrete modifier using the seal - Google Patents

Description

The present invention relates to a concrete reforming technique, and more specifically, to detect and confirm that a concrete modifier (including what is called a concrete protective agent , the same applies hereinafter) is applied to a concrete structure. The present invention relates to a sealing material and a method for detecting construction of a concrete modifier using the sealing material.

By applying or spraying on the surface of concrete structures, it penetrates deeply into the concrete and reacts with concrete components such as calcium hydroxide, calcium carbonate, calcium bicarbonate to form inorganic crystals, and continuous pores in the concrete. In recent years, concrete modifiers that prevent the entry of harmful substances such as acid rain, salt, and carbon dioxide gas by densifying, suppress concrete deterioration, and extend the durability of concrete have attracted attention in recent years. Yes. Such concrete modifiers are disclosed in the following patent documents.
Japanese Patent No. 2937309 JP 2004-131316 A JP 2004-323333 A

However, since such a concrete modifier is a colorless and transparent liquid mainly composed of alkali silicate or the like, it is difficult to visually confirm that this has been applied. For this reason, construction is currently under the orderer's presence, but with the expansion of demand, the construction of a quality certification and on-site management system is urgently needed.

Accordingly, an object of the present invention is to provide a novel method capable of easily, surely and objectively confirming that an appropriate amount of concrete modifier has been applied to the surface of a concrete structure. .

In order to solve this problem, the present invention according to claim 1 is a sealing material for detecting that an alkaline concrete modifier is applied to the surface of a concrete structure, and is included in the concrete modifier. Reaction layer that quantitatively reacts with the alkali generated and discolors, the adhesive layer, and the alkali component eluted from the concrete structure when it is attached to the concrete structure by the adhesive layer reaches the back side of the reaction layer and reacts A concrete modifier construction confirmation seal comprising a blocking layer provided between a reaction layer and an adhesive layer in order to prevent discoloration of the layer.

According to a second aspect of the present invention, in the seal for confirming the concrete modifier construction according to the first aspect, the reaction layer is formed by impregnating the base material with an acid and an indicator and then drying, and sprayed onto the concrete structure. When the alkali contained in the concrete modifier penetrated into the water-absorbing base material of the reaction layer and neutralized with the acid, the indicator showed a color reaction, so that an appropriate amount of concrete modifier was applied. It is characterized by confirming that.

  The present invention according to claim 3 is the concrete modifier construction confirmation seal according to claim 2, wherein the acid contained in the reaction layer is a liquid or solid acidic substance at room temperature, and the indicator is between pH 3 and pH 11. It is a pH indicator that changes color.

The present invention according to claim 4 uses the concrete modifier construction confirmation seal according to any one of claims 1 to 3, and the concrete modifier is to be constructed through the adhesive layer on the back surface. was attached to the dotted state at an appropriate interval on the surface of the object, sprayed concrete modifier on the surface of the concrete modifier construction confirmation seal is pasted concrete structure, after a predetermined time has elapsed, wherein the appropriate amount of concrete modifier verify that it is the construction by observing visually color change of the concrete modifiers construction confirmation seal of the reaction layer, a concrete modifier construction confirmation method.

The present invention according to claim 5 is the concrete modifier construction confirmation method according to claim 4, wherein the concrete modifier is sprayed on the surface of the concrete structure and then the concrete modifier construction confirmation seal is covered on the surface. The reaction layer is covered by sticking a sheet.

According to a concrete modifier construction confirmation seal and concrete modifier construction confirmation method using the sealing of the present invention, the visually that the appropriate amount of concrete modifier is sprayed and construction to the surface of the concrete structure Can be confirmed easily, reliably and objectively.

FIG. 1 is a cross-sectional view showing a state in which a concrete modifier construction confirmation seal 1 according to an embodiment of the present invention is attached to the surface of a concrete structure 6.

This concrete modifier construction confirmation seal 1 is a laminate having a reaction layer 2 on the front surface side, an adhesive layer 3 on the back surface side, and a blocking layer 4 between them. It is formed in a circular shape having a certain diameter.

The reaction layer 2 is formed by dropping an acid and an indicator onto a substrate and drying them, and uniformly impregnating them all over the substrate. As the water-absorbing substrate, for example, filter paper, woven fabric, knit, non-woven fabric, and sponge can be used. The present invention applies the principle of neutralization titration to contain an alkali (strong alkali, silica, etc.) and an equivalent acid contained in the reaction layer 2 when a specified amount of concrete modifier is sprayed. In addition, a rapid change in pH value when these are neutralized is detected by the color reaction of the indicator.

  The acid can be any liquid or solid acidic substance (mineral acid, organic acid), for example ascorbic acid, formic acid, citric acid, succinic acid, salicylic acid, propionic acid, malic acid, valeric acid, tartaric acid, acetic acid. Organic acids such as lactic acid, butyric acid, oxalic acid, pyrophosphoric acid, hydrofluoric acid, borohydrofluoric acid, boric acid, polyphosphoric acid, iodic acid, phosphoric acid, phosphorous acid, sulfurous acid, hydrochloric acid, chloric acid, periodic acid, perbromine An inorganic acid such as acid, bromic acid, nitric acid or sulfuric acid, or an arbitrary mixture thereof can be used. However, hydrochloric acid volatilizes in a short time and is not preferable for the use of the present invention. From the results, it is considered that phosphoric acid, citric acid, and boric acid can be particularly preferably used.

  Indicators include p-nitrophenol, alizarin yellow R (AZY), cresol red, chlorophenol red, congo red, thymolphthalein, thymol blue, tetrabromophenol blue, tropeoline 000, neutral red, phenolphthalein, phenol red , Bromocresol green, bromocresol purple, bromothymol blue (BTB), bromophenol blue, bromophenol red, methyl yellow, methyl orange, methyl red, or a mixture thereof can be used. Phthalene is considered suitable.

The adhesive layer 3, the concrete modifier construction confirmation seal 1, since it is intended for sticking to the surface of the concrete structure 6 to be applying a concrete modifier, its surface of the concrete structure 6 to In addition to being required to exhibit sufficient adhesive strength, it also exhibits sufficient adhesive strength to the barrier layer 4 laminated on the surface side thereof, and the surface temperature of the concrete structure 6 is 50 in the summer. Because it can reach -60 ° C, it must have heat resistance that can maintain the adhesive force even under such temperature conditions. Is required.

  The blocking layer 4 is interposed between the reaction layer 2 and the adhesive layer 3 to prevent alkali components eluted from the concrete structure 6 from reaching the back side of the reaction layer 2 and discoloring the reaction layer 2. To play a role. In addition to being able to sufficiently adhere to the adhesive layer 3 as described above, the material of the blocking layer 4 has durability that is not affected by the acid contained in the reaction layer 2, and is deformed even under the above temperature conditions. From these viewpoints, plastics such as polyethylene, polypropylene, and polystyrene are suitable as the constituent material of the blocking layer 4.

Although not shown, since a large amount of water is used for the construction of the concrete modifier , a water absorbing layer is provided on the front side and / or the back side of the reaction layer 2 in order to eliminate the influence of this water. You may comprise the concrete modifier construction confirmation seal | sticker 1 of this invention.

The concrete modifier construction confirmation seal 1 configured as described above is used by being affixed to the surface of a concrete structure 6 on which the concrete modifier is to be applied in a dotted state at a predetermined interval. After that, as a work to improve and improve the concrete (long life or high durability), the concrete modifier 6 is adhered to the surface of the concrete structure 6 on which the concrete modifier construction confirmation seal 1 is attached in a scattered state. Spray the material with a spray. Spray concrete modifier is carried along the installation instructions provided by the manufacturing vendor of the concrete modifier. Since the concrete modifier sprayed in the specified amount contains a predetermined amount of alkali, it is neutralized with an equivalent amount of acid contained in the reaction layer 2 of the concrete modifier construction confirmation seal 1. The indicator contained in the reaction layer 2 also exhibits a color reaction due to a sudden pH change, so that it is easy, surely and objectively confirmed that a specified amount of concrete modifier has been applied. .

After the concrete modifiers construction confirmation seal 1 was sprayed concrete modifier on the surface of the concrete structure 6 affixed to scattered state, the cover promptly, concrete modifiers construction confirmation seal first surface It is preferable to cover the reaction layer 2 by sticking the sheet 5. Thereby, the preservability of the discolored seal can be improved. Moreover, it prevents that the alkaline component eluted from the concrete structure 6 reaches the surface side of the reaction layer 2 through the surface of the concrete structure 6 and changes the color of the reaction layer 2. The cover sheet 5 can be formed of, for example, stainless steel, a plastic film, or cardboard.

<Test example>
As described above, the present invention applies the principle of neutralization titration to the acid (equivalent to alkali (strong alkali, silica, etc.)) contained in a specified amount of sprayed concrete modifier, and An indicator that exhibits a color reaction due to a rapid pH change that occurs when a neutralization reaction occurs is included in the reaction layer 2, so that it is possible to confirm a suitable acid and indicator to be included in the reaction layer 2. A test was conducted.

A commercially available thin quantitative filter paper (ADVANTEC (registered trademark, Toyo Filter Paper) 5A) having a diameter of 110 mm is cut into 1/4 (about 24.2 cm ² ), and then an appropriate amount is dropped so that the indicator soaks into the entire cut filter paper. Then, it was dried indoors (about 20 ° C.), and further 0.6 ml of the reagent acid was dropped with a measuring pipette so as to soak into the entire cut filter paper and dried indoors (about 20 ° C.). The acid amount per cm ² is about 0.012 meq. The edge part of this cut filter paper was cut about 2 mm, and the test body of 2 cm x 2 cm was created. Use 4 types of solutions of phenolphthalein, methyl orange, BTB, and alizarin yellow as indicators, and use 6 types of acids as hydrochloric acid, sulfuric acid, phosphoric acid, boric acid, acetic acid, citric acid, and combine them. Thus, a total of 24 types of test bodies were prepared. These specimens correspond to the reaction layer 2 in the concrete modifier construction confirmation seal 1 of the present invention.

As the concrete modifier , commercial products of lithium silicate system and sodium silicate system were used, and the stock solution of the commercial product was diluted with water 3 times, 10 times and 100 times with 33% diluted solution, 10% diluted solution and 1 % Dilutions were prepared. When these pH values were measured, they were 11.41, 11.31 and 10.68, respectively. In addition, according to the instruction manual of the commercial product, it should be sprayed at a spray amount of 0.05 L / m ² (= 0.005 ml / cm ² ) per time as a 33% diluted solution. The amount of alkali per unit is about 0.012 meq / cm ² .

Each test specimen was placed on a paper towel, and each dilution sample of the concrete modifier was sprayed downward from 5 cm above. The spray amount of the diluted sample was about 0.15 g≈0.15 ml, and the spray amount per cm ² was about 0.012 ml because it was sprayed on a circular area of 4 cm in diameter including the test specimen. Therefore, since the amount of acid that is supposed to be present in the test body cm ² by one spray is 0.004 meq, the experiment was performed with the number of sprays being 3 times based on the concentration of 33.3%.

In the 33% diluted solution, the amount of alkali by one spraying was 0.004 meq per 1 cm ² of cut filter paper of the test specimen. Since the amount of the acid soaked in the test body in advance is about 0.012 meq per 1 cm ² of the test body, when the 33% dilution liquid is used as a standard, the acid of the test body is moderated by spraying the dilution liquid three times. Will be summed. Based on the above, the experiment was performed with the number of sprays set to three.

  As can be seen from the test results shown in FIGS. 2 to 6, a clear color reaction was confirmed when the 33.3% dilution sample was sprayed, and compared with the 10% dilution sample and the 1% dilution sample. Even so, it was confirmed that there was a big difference in the color reaction.

  However, there were some test specimens in which the filter paper deteriorated easily due to acid and indicator, and test specimens in which the indicator deteriorated and discolored. Therefore, the residual acid condition after drying, the deterioration condition of the filter paper, Each of the items of indicator deterioration state and clarity of indicator color reaction was evaluated for each acid and indicator. This result is shown in FIG. 7. Acids that are considered particularly suitable are phosphoric acid, citric acid, hydrochloric acid, and boric acid. However, hydrochloric acid has a property of easily evaporating, and is not suitable for the use of the present invention. It is believed that there is. Indicators that are considered to be particularly suitable are AZY and phenolphthalein, but methyl orange also has a relatively stable color reaction with few spots, so it can be used suitably depending on the type of acid to be combined. It is thought to get.

It is sectional drawing which shows the state which affixed the concrete modifier construction confirmation seal | sticker by one Embodiment of this invention on the surface of a concrete structure. It is a graph which shows the color reaction condition of the test body which used the phenolphthalein solution as an indicator. It is a chart which shows the color reaction condition of the test body which used the methyl orange solution as an indicator. It is a chart which shows the color reaction condition of the test body which used the BTB solution as an indicator. It is a graph which shows the color reaction condition of the test body which used the AZY solution as an indicator. It is an evaluation table for predicting the acid and indicator suitably used for a reaction layer.

Explanation of symbols

1 Seal for confirming concrete modifier construction 2 Reaction layer 3 Adhesive layer 4 Barrier layer 5 Cover sheet 6 Concrete structure

Claims (5)

A sealing member for detecting the alkaline concrete modifier is construction on the surface of the concrete structure, and a reaction layer which changes color quantitatively reacted to alkali contained in concrete modifier, adhesive In order to prevent the alkali component eluted from the concrete structure from reaching the back side of the reaction layer and causing the reaction layer to discolor when it is attached to the concrete structure by the layer and the adhesive layer. And a barrier layer provided between the layers, and a concrete modifier construction confirmation seal. The reaction layer is formed by impregnating the base material with acid and indicator and then drying, and the alkali contained in the concrete modifier sprayed on the concrete structure penetrates into the water-absorbing base material of the reaction layer and causes acid and medium. 2. The concrete modifier construction confirmation seal according to claim 1, wherein when the sum reaction is carried out, the indicator shows a color reaction to confirm that an appropriate amount of the concrete modifier has been applied. 3. The concrete modifier for construction confirmation according to claim 2, wherein the acid contained in the reaction layer is a liquid or solid acidic substance at room temperature, and the indicator is a pH indicator that changes color between pH 3 and pH 11. sticker. The concrete modifier construction confirmation seal according to any one of claims 1 to 3, wherein the seal is placed at an appropriate interval on the surface of the concrete structure where the concrete modifier is to be constructed through an adhesive layer on the back surface. was attached to the scattered state, sprayed concrete modifier on the surface of the concrete modifier construction confirmation seal is pasted concrete structure, after a predetermined time has elapsed, the concrete modifiers construction confirmation seal an appropriate amount of concrete modifier by visually observing the color change of the reaction layer is characterized to confirm that it has been construction, concrete modifiers construction confirmation method. After the concrete modifier was sprayed onto the surface of the concrete structure, characterized by covering the reaction layer by adhering the cover sheet to the concrete modifiers construction confirmation seal surface, the concrete of claim 4, wherein Confirmation method of modifier installation.

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