JP2017101401A - Acid resistant floor, construction method of the same and repairing method of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an acid resistant floor in which a surface of concrete can be protected from etching by acid liquid and durability is high, and provide a construction method of the acid resistant floor and a repairing method of the acid resistant floor.SOLUTION: A construction method of an acid resistant floor 1 is provided in which an acid resistant layer 5 is formed on the surface of a concrete foundation 2. A coating agent assuming an epoxy resin as a raw material is applied on a surface 2a of the concrete foundation 2, after a moisture content of the placed concrete foundation 2 becomes 8% or less. The acid resistant layer 5 having high adhesiveness to the concrete foundation 2 can be formed, and therefore decrease in physical strength of the acid resistant layer 5 due to peeling can be made hard to occur.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an acid resistant floor, an acid resistant floor construction method, and an acid resistant floor repair method. More specifically, the present invention relates to an acid resistant floor constructed in a place where a highly corrosive liquid such as sulfuric acid or hydrochloric acid is used, and a construction method for constructing the acid resistant floor.

  Conventionally, in places and buildings where highly corrosive liquids and chemicals are used, if the floor made of concrete is used as is, the concrete floor will be corroded by the liquid and chemicals, resulting in severe damage to the floor. . For this reason, in such a building, a coating having corrosion resistance, chemical resistance and the like is applied to the surface of the concrete floor. For example, in the electrolytic smelting process in copper electrolytic smelting, a strongly acidic electrolytic solution is used. Therefore, in a building where an electrolytic cell is installed, a floor material having acid resistance is used for the floor.

  As a method for coating the surface of such a concrete floor, there is a technique described in Patent Document 1. In the technique of this Patent Document 1, construction is performed by the following method.

First, as a first primer, a polyurethane polymer containing cement is applied to the base concrete by glazing or brushing, and then a second primer not containing cement is brushed on the surface of the first primer.
Next, a fiber glass, a curing agent, and vinyl ester or a copolymer resin of vinyl ester and polyester are kneaded and coated on the surface of the second primer. Then, an undercoat layer is formed.
Then, using ceramic as an aggregate, a paste obtained by kneading the ceramic, a curing agent, and a vinyl ester or a copolymer resin of vinyl ester and polyester is applied to form an intermediate coating layer.
Finally, if a vinyl ester containing ceramic or a copolymer resin of vinyl ester and polyester and a hardener are kneaded into a paste, thinly coated for finishing and forming a topcoat layer, The coating is complete.

And in the technique of this patent document 1, there exists description that corrosion resistance and crack resistance can be ensured by forming the undercoat layer containing fiber glass.
In addition, there is a description that the curing time of the undercoat layer and the intermediate coat layer is accelerated, the curing time until opening after construction is shortened, and the floor construction method is suitable for repair and repair.

Japanese Patent No. 2900024

  However, in the technique of Patent Document 1, the corrosion resistance and the like are ensured by the undercoat layer including fiberglass. However, when fiberglass is inserted, the management of the moisture content becomes strict during construction. Moreover, after construction, the coating layer is easily peeled off due to insufficient adhesive force, and the problem arises that the coating layer peels off at the surface when peeling off.

  Further, when the coating layer is formed on the surface of the ground concrete, a gap may be formed between the coating layer and the ground if the adhesion between the coating layer and the ground concrete is poor. If such a gap is formed, the coating layer is easily lifted from the base. If the coating layer is lifted, the coating layer is easily cracked or cracked when an impact is applied to that portion. If cracks, cracks, and the like are formed, liquid or the like enters from the portion, and the underlying concrete is corroded by the liquid or the like. However, in the technique of Patent Document 1, although there is a description that the surface of the concrete base itself can be prevented by providing the coating layer, there is no mention of the adhesion between the coating layer and the base concrete. .

  In view of the above circumstances, the present invention provides an acid-resistant floor, an acid-resistant floor construction method, and an acid-resistant floor repair method that can protect the surface of concrete from corrosion by acidic liquid and have high durability. Objective.

(Construction method of acid-resistant floor)
The acid-resistant floor construction method of the first invention is an acid-resistant floor construction method in which an acid-resistant layer is formed on the surface of the concrete base, and the moisture content of the cast concrete base becomes 8% or less. A coating agent made of an epoxy resin is applied to the surface of the concrete base.
The construction method of the acid-resistant floor according to the second aspect of the present invention is the method according to the first aspect, wherein the water content of the cast concrete base is 6.5% or less, and the surface of the concrete base is coated with an epoxy resin material. It is characterized by applying.
The construction method of the acid-resistant floor of the third invention is characterized in that, in the first or second invention, the surface of the concrete base is rubbed before the coating agent is applied.
The construction method of the acid resistant floor of the fourth invention is characterized in that, in the third invention, the surface of the concrete base is rubbed with a force capable of removing the latency existing on the surface of the concrete base.
The construction method of the acid resistant floor of the fifth invention is characterized in that, in the fourth invention, the surface of the concrete base is polished.
The construction method of the acid-resistant floor of the sixth invention is characterized in that, in the first, second, third, fourth or fifth invention, the concrete base is formed by using a fast-hardening cement.
The construction method of the acid resistant floor of the seventh invention is characterized in that, in the sixth invention, the fast-hardening cement is non-shrinkage or low shrinkage cement mortar.
(Acid-resistant floor)
The acid resistant floor of the eighth invention is a floor in which an acid resistant layer is formed on the surface of a concrete floor,
It is characterized by comprising a concrete base and an acid-resistant layer formed by applying a coating agent made of an epoxy resin in a state where the moisture content of the concrete base is 8% or less to the surface of the concrete base. .
The acid-resistant floor of the ninth invention is characterized in that, in the eighth invention, the acid-resistant layer is formed by applying the concrete base with a moisture content of 6.5% or less.
The acid-resistant floor of the tenth invention is characterized in that, in the eighth or ninth invention, the peel strength of the acid-resistant layer is 1.5 N / mm ² or more.
The acid-resistant floor according to the eleventh aspect of the invention is characterized in that, in the eighth, ninth, or tenth aspect, the acid-resistant floor is formed by any one of the first to seventh aspects.
(How to repair acid-resistant floors)
An acid-resistant floor repair method according to a twelfth aspect of the invention is an acid-resistant floor repair method in which an acid-resistant layer is formed on the surface of a concrete floor, wherein the acid-resistant layer at the repair site and the surface portion of the concrete floor at the repair site A spacer is disposed at the boundary between the removal step formed by removing the acid-resistant layer and the surface portion of the concrete floor by the removal step and the existing portion of the acid-resistant floor; Placing a concrete to form a repair concrete foundation, and forming an acid-resistant layer that forms a repair floor by forming a repair acid-resistant layer on the surface of the repair concrete foundation placed in the placement process And after the repair acid-resistant layer is formed by the step and the acid-resistant layer forming step, the spacer is removed, and the space formed by removing the spacer is filled with an elastic sealant. To.
An acid-resistant floor repair method according to a thirteenth aspect of the invention is characterized in that, in the twelfth invention, the repair floor portion is formed by any one of the first to seventh inventions.

(Construction method of acid-resistant floor)
According to the first invention, an acid-resistant layer having high adhesion to the concrete base can be formed, and therefore it is possible to make it difficult for the physical strength of the acid-resistant layer to decrease due to peeling.
According to the 2nd invention, the adhesiveness with respect to a concrete foundation can be made higher.
According to the 3rd and 4th invention, since a weak part is removed in the surface of a concrete foundation, an acid-resistant layer becomes difficult to peel from a concrete foundation.
According to the 5th invention, since the adhesiveness of the acid-resistant layer with respect to a concrete foundation can further be improved, the physical strength of the acid-resistant layer caused by peeling can be made less likely to occur.
According to the sixth and seventh inventions, since the adhesion between the acid-resistant layer and the concrete base is high, it is possible to make it difficult for the physical strength to decrease due to the peeling of the acid-resistant layer. In addition, since the time until the acid-resistant layer is constructed can be shortened, the construction period can be shortened.
(Acid-resistant floor)
According to the eighth invention, since the adhesion between the acid-resistant layer and the concrete base is high, the physical strength of the acid-resistant layer is hardly lowered due to peeling. Then, even if a mechanical impact is applied, the acid resistant layer is less likely to be damaged, so that the acid resistance is easily maintained.
According to the 9th invention, the adhesiveness with respect to a concrete foundation can be made higher.
According to the tenth aspect, since the peel strength of the acid resistant layer is high, the physical strength of the acid resistant layer is hardly lowered due to the peel.
According to the eleventh aspect, a floor having high adhesion between the acid-resistant layer and the concrete base can be formed.
(How to repair acid-resistant floors)
According to the twelfth aspect, since the space formed by removing the spacer is filled with the elastic sealant, even if the repair floor shrinks, the existing part and the repair floor by the sealant. It is possible to prevent a gap or a crack from being generated between the two.
According to the thirteenth invention, it is possible to form a repair floor portion having high adhesion between the acid-resistant layer and the concrete base.

(A) is schematic explanatory drawing of the acid resistant floor 1 of this invention, (B) is schematic explanatory drawing of the acid resistant floor 1 in which the repair floor part 10 was formed. FIG. 3 is a schematic explanatory diagram of an operation for forming the repair floor portion 10. It is the table | surface and graph which showed the experimental result. It is the figure which showed the experimental result.

  The acid-resistant floor construction method of the present invention is a method of forming an acid-resistant layer on the surface of a floor formed of concrete, and has a feature that durability against an impact such as dropping of an object is increased. Yes.

  The place where an acid-resistant floor is formed by the method for constructing an acid-resistant floor according to the present invention is a place where a highly corrosive acidic liquid is used, and the place is not particularly limited. For example, a floor where an electrolytic bath for copper electrolytic smelting is installed, an indoor / outdoor scene where an acidic liquid flows out, a breakwater, and the like can be given.

  The acid-resistant floor formed by the acid-resistant floor construction method of the present invention has alkali resistance as long as the material of the acid-resistant layer has resistance (alkali resistance) to an alkaline liquid. In other words, when a material having resistance to both acidic liquid and alkaline liquid is used as the material of the acid-resistant layer, a floor having both acid resistance and alkali resistance can be obtained by the acid-resistant floor construction method of the present invention. Can be formed.

(Construction method of acid-resistant floor of the present invention)
Hereinafter, although the construction method of the acid resistant floor of this invention is demonstrated, first, the structure of the acid resistant floor 1 (namely, acid resistant floor 1 of this invention) formed by the acid resistant floor construction method of this invention is simplified. explain.

  As shown in FIG. 1 (A), the acid-resistant floor 1 of the present invention comprises a concrete base 2 and an acid-resistant layer 5 formed on the surface 2a of the concrete base 2.

(Concrete substrate 2)
The concrete base 2 is a portion formed of concrete made of cement. In this specification, concrete includes all cement paste mixed with cement, water, mortar mixed with cement, water and fine aggregate, and concrete mixed with cement, water, fine aggregate and coarse aggregate. Yes. That is, the concrete base 2 may be formed using any one of cement paste, mortar, and concrete according to the use of the floor to be formed and the required properties. Moreover, cement paste, mortar, and concrete may contain substances other than the above materials (for example, copper slag, green sand, fly ash, blast furnace slag, etc.).

  The cement used for this concrete base 2 can also use the cement marketed normally. For example, general Portland cement, early-strength cement, fast-hardening cement, or the like can be used. In particular, those having low shrinkage or non-shrinkage are preferred when cured. If the concrete base 2 is formed using such cement as a material, the adhesion between the acid-resistant layer 5 and the concrete base 2 is increased. In addition, deformation of the acid-resistant layer 5 due to shrinkage of the concrete base is less likely to occur. Therefore, it is possible to make it difficult for the physical strength of the acid-resistant floor 1 to decrease due to the peeling of the acid-resistant layer 5.

  In addition, if the concrete base 2 is formed using fast-strength cement or fast-hardening cement as the material, the time required to construct the acid-resistant layer 5 on the surface 2a of the concrete base 2 can be shortened, so the construction period can be shortened. For example, as will be described later, when the acid-resistant layer 5 is constructed after the moisture content of the concrete base 2 is 8% or less, the time until the moisture content is reached can be shortened. Can do.

(Acid resistant layer 5)
As shown in FIG. 1A, the acid resistant layer 5 is formed on the surface 2 a of the concrete base 2. The acid resistant layer 5 is formed so that the primer layer 6, the resin mortar layer 7, and the top coat layer 8 are arranged in this order from the surface 2 a of the concrete base 2.

(Primer layer 6)
The primer layer 6 is a layer formed on the surface 2 a of the concrete foundation 2 and has a function of bonding the surface 2 a of the concrete foundation 2 and the resin mortar layer 7. This primer layer 6 is formed of a material substantially equivalent to the resin mortar layer 7.
Since the primer layer 6 has the above functions as its main function, the primer layer 6 is formed to be thinner than the resin mortar layer 7 (for example, 10% or less of the acid resistant layer 5).

(Resin mortar layer 7)
The resin mortar layer 7 is formed on the surface of the primer layer 6. The resin mortar layer 7 is a layer that mainly exhibits acid resistance in the acid resistant layer 5. In the acid-resistant floor 1 of the present invention, the resin mortar layer 7 is formed of a resin mortar whose main material is an epoxy resin. As this resin mortar, for example, one formed by mixing an epoxy resin, benzyl alcohol and propylene glycol monomethyl ether can be used.

  As this resin mortar, the product name: Arrow Resin R-115N by Arrow Chemical Co., Ltd. can be mentioned. The resin mortar layer 7 can be formed by applying the resin mortar as a main agent and a mixture of the main agent and a curing agent to the surface of the primer layer 6. Hereinafter, what mixed the hardening | curing agent with the main ingredient is only called resin mortar material. A material used for forming the primer layer 6 by mixing a curing agent with the main agent is simply referred to as a primer material.

  In addition, the hardening | curing agent mixed with this main ingredient is not specifically limited. For example, a curing agent made of tritetraamine (for example, product name: Arrow Resin H-110N manufactured by Arrow Chemical Co., Ltd.) or a modified aromatic polyamine (for example, product name: ML-2 manufactured by Kyodo Chemical Co., Ltd.) is used. can do.

(Topcoat layer 8)
The top coat layer 8 is a layer formed on the surface of the resin mortar layer 7. The top coat layer 8 is also formed of a material substantially equivalent to the resin mortar layer 7, similarly to the primer layer 6. The top coat layer 8 is provided to protect the resin mortar layer 7 and improve the appearance of the acid resistant layer 5. That is, the top coat layer 8 is provided in order to provide the acid resistant layer 5 with functions other than the essential function (acid resistance) of the acid resistant layer 5 required for the resin mortar layer 7. This topcoat layer 8 may be a single layer or two or more layers. A material used for forming the topcoat layer 8 by mixing a curing agent with the main component of the resin mortar layer 7 is simply referred to as a topcoat material.

  In the acid resistant floor 1 having the above structure, the acid resistant layer 5 and the surface 2a of the concrete base 2 have high adhesiveness, so that the acid resistant layer 5 is difficult to peel off from the surface 2a of the concrete base 2. . When peeling occurs, a gap (space) is formed between the acid-resistant layer 5 and the surface 2a of the concrete foundation 2, so that when a mechanical shock is applied to the acid-resistant floor 1, the acid-resistant layer The layer 5 is easily cracked or cracked. However, with the acid-resistant floor 1 as described above, since the adhesion between the acid-resistant layer 5 and the surface 2a of the concrete base 2 is high, the physical strength of the acid-resistant layer 5 is hardly reduced due to peeling. . Then, even if a mechanical impact is applied, the acid resistant layer 5 is not easily damaged, so that the acid resistance of the acid resistant floor 1 can be easily maintained.

(Peel strength)
For such acid-resistant floor 1, the peel strength of the acid resistant layer 5 is preferably 1.5 N / mm ² or more, more preferably it is desirable to form so that the 2.0 N / mm ² or more. With such peel strength, it is possible to prevent the acid-resistant layer 5 from peeling from the concrete base 2 for a long time in the acid-resistant floor 1.

  In the above example, the primer layer 6, the resin mortar layer 7, and the topcoat layer 8 are provided. However, the above three layers are not necessarily provided. That is, as long as a predetermined function (acid resistance) can be exhibited, only one layer or only two layers may be provided. For example, only the resin mortar layer 7 may be provided, the primer layer 6 and the resin mortar layer 7 may be two layers, or the resin mortar layer 7 and the topcoat layer 8 may be two layers.

(Construction method for acid-resistant floor 1)
The acid-resistant floor 1 mentioned above can be constructed by various methods. An example of the construction method is shown below. When constructed by the method shown below, the acid-resistant floor 1 having high adhesion between the acid-resistant layer 5 and the concrete base 2 can be formed.

  First, the concrete base 2 of the acid resistant floor 1 is formed. The concrete base 2 is formed by placing concrete or the like made of cement as described above.

  The cast concrete base 2 is cured only for a predetermined period, and then an acid-resistant layer 5 is formed on the surface thereof. The predetermined curing period is appropriately adjusted depending on the cement used for the concrete. Specifically, curing is performed until the moisture content of the concrete base 2 becomes 8% or less. The period until this state changes depends on factors such as weather and seasons. For example, the moisture content of the concrete base 2 is 8% or less in about 48 hours for normal ordinary Portland cement, about 36 hours for fast-hard cement, and about 3 to 4 hours for fast-hard cement.

  In addition, when placing the concrete foundation 2, the work generally performed when placing concrete is naturally performed. For example, wrinkle control or the like is performed at the time of placing and / or during the curing period.

  When the moisture content of the concrete base 2 is 8% or less, an operation of rubbing the surface 2a of the concrete base 2 is performed. By performing this work, if there is a latency on the surface 2a of the concrete foundation 2, the latency is removed. As a method of rubbing the surface 2a of the concrete base 2, for example, a wire brush, an electric polishing machine, or the like can be used.

  When the operation of rubbing the surface 2a of the concrete base 2 is completed, the concrete powder generated by rubbing is removed from the surface 2a of the concrete base 2, and the primer material is applied to the surface 2a of the concrete base 2.

  After the primer material is applied, when the primer material is cured to some extent and the primer layer 6 is formed, the resin mortar material is applied.

  When the resin mortar layer 7 is formed before the resin mortar material is completely cured after the resin mortar material is applied, the top coat layer 8 material is applied.

  And if all the layers which comprise the acid resistant layer 5 dry and solidify, construction of the acid resistant floor 1 will be completed.

  In addition, if the work of rubbing the surface 2a of the concrete base 2, that is, the work of forming the acid-resistant layer 5 on the surface 2a of the concrete base 2, is performed after the moisture content of the concrete base 2 becomes 8% or less, peeling Strength can be increased. In particular, if the acid-resistant layer 5 is formed after the moisture content is 6.5% or less, the peel strength can be easily increased.

  Moreover, the operation | work which rubs the surface 2a of the concrete base 2 does not necessarily need to be performed. For example, if the adhesive with the resin mortar that is the main ingredient of the acid-resistant layer 5 (such as high peel strength), such as concrete using fast-hardening cement, without rubbing work, The acid resistant layer 5 may be formed on the surface 2 a of the concrete base 2. However, if the concrete base 2 is formed of concrete using ordinary Portland cement, the peel strength can be brought close to that of fast-hardening cement by performing a rubbing operation.

  In particular, regardless of the type of cement, if the surface 2a of the concrete substrate 2 is polished, the adhesion between the surface 2a of the concrete substrate 2 and the acid-resistant layer 5 is improved, and the peel strength can be further increased. For example, it is assumed that the acid-resistant layer 5 is peeled off from the surface 2a of the concrete base 2 when the peel test is performed. Even in such a case, if the surface 2a of the concrete base 2 is polished, the adhesion between the surface 2a of the concrete base 2 and the acid-resistant layer 5 can be strengthened.

  For example, if the surface 2a of the concrete base 2 is polished, the concrete base 2 can be strengthened to a state where peeling occurs due to the destruction of the concrete base 2. If it is in such a state, even if time passes after construction, it will become difficult to be in the state where the acid-resistant layer 5 floated from the surface 2a of the concrete foundation 2. Then, even when an impact is applied to the acid-resistant floor 1, the acid-resistant layer 5 is hardly damaged, so that the concrete base 2 of the acid-resistant floor 1 can be prevented from being damaged. That is, the durability of the acid resistant floor 1 can be increased.

  In addition, the method of grind | polishing the surface 2a of the concrete base 2 is not specifically limited. Polishing may be performed using a polishing apparatus (for example, K-30 series, K-60 series, Ultra Thunder (handy type) manufactured by LINAX Corporation) to clean or clean the surface. Further, after polishing using an abrasive, surface finishing (for example, polishing with sandpaper) may be performed.

(Repair method for acid-resistant floor 1)
Although the construction method of the acid-resistant floor mentioned above is employ | adopted when constructing a new floor, the same method is employable also when repairing the damaged acid-resistant floor. Then, since the peeling of the acid resistant layer 5 at the repaired portion can be prevented, durability can be enhanced.

In particular, when repairing a damaged acid-resistant floor, construction is performed so that the sealing agent 30 made of resin mortar is arranged at the boundary between the existing part and the repaired floor part (hereinafter referred to as the repair floor part 10). It is desirable to do. Then, even if the repair floor 10 contracts due to the effect of drying or solidification, it is possible to prevent a gap or a crack from being generated between the existing part A and the repair floor 10 by the sealing agent.
Hereinafter, although the repair method of the acid-resistant floor 1 is demonstrated based on FIG. 1 (B) and FIG. 2, the part which becomes substantially equivalent to the construction method of the acid-resistant floor 1 mentioned above is omitted suitably.

  First, in the acid-resistant floor 1, check the part where dents etc. occur when a load is applied (the part damaged by corrosion of the concrete foundation 2), and the acid-resistant layer 5 and the concrete foundation in this place (repair part) 2 surface portion is removed (removal step). The surface portion of the concrete base 2 here means a portion where the concrete base 2 is corroded by an acid or the like. Therefore, in the removing step, the concrete foundation 2 is removed until a portion of the concrete foundation 2 where corrosion has not occurred is exposed. Then, a depression (removal portion 1h) that is recessed from the surface is formed in the existing acid-resistant floor 1 (FIG. 2A).

  Next, concrete is placed in the removed portion 1h. At this time, the spacer S is installed at the boundary between the existing part of the acid-resistant floor 1 and the removed part 1h. Then, concrete is cast in the removed portion 1h, and the repair concrete base 12 on which the spacer S is arranged is formed (placement step) (FIG. 2B).

The spacer S is removed after the repair concrete base 12 is hardened, so that the spacer S is made of a material that is not combined with concrete.
The spacer S is disposed so that at least the upper surface thereof is flush with the surface 1 a of the existing acid-resistant floor 1 or protrudes from the surface of the acid-resistant floor 1.

  When the repair concrete base 12 is cured for a predetermined period, a repair acid resistant layer 15 is formed on the surface of the repair concrete base 12 (acid resistant layer forming step). The repaired acid-resistant layer 15 has a structure substantially equivalent to the above-described new acid-resistant floor 1. That is, the primer material, the resin mortar material, and the topcoat material are applied in this order on the surface of the repair concrete base 12, and the repair acid-resistant layer 15 is formed.

  When the repair acid-resistant layer 15 is formed by the acid-resistant layer forming step, the spacer S is removed. Then, a space 10 h is formed in the portion where the spacer S is disposed between the repair concrete foundation 12 and the repair acid-resistant layer 15 and between the acid-resistant layer 5 of the acid-resistant floor 1 and the concrete foundation 2. This space is filled with a sealant 30 having elasticity. And when this sealing agent hardens | cures, construction of the repair floor part 10, ie, the repair of the acid-resistant floor 1, is completed (FIG. 1 (B)).

  And when the repair floor part 10 is formed by the above methods, the sealing agent 30 which has a stretching property is filled in the space formed by removing the spacer S. For this reason, even if the repair floor 10 contracts or the like, it is possible to prevent a gap or a crack from being generated between the existing part and the repair floor 30 by the sealing agent 30.

  The sealant 30 to be used is not particularly limited as long as it has good adhesion to concrete and has a certain degree of stretchability. An epoxy resin-based sealant (for example, product name: Tough Seal CE-520 manufactured by Albert Kogyo Co., Ltd.) can be used.

The peel strength of the acid-resistant floor of the present invention was confirmed.
In the experiment, the concrete base was formed from concrete (cement paste) using a plurality of cements, an acid-resistant layer was formed on the surface, and the peel strength was measured.

  The acid resistant layer was formed by curing the concrete for a certain period, and then forming an acid resistant layer on the concrete surface. In addition, before the acid-resistant layer is formed, no special treatment is performed on the concrete surface.

  The peel strength was carried out based on a peel test (NNK-005) certified by the Japan Coating Floor Association. The peel strength in the peel test was measured using a tensile tester (manufactured by Rex Corporation, model number: Techno Tester R-10000ND).

  The moisture content of the concrete was measured using a concrete mortar moisture meter (model number: HI-520-2 manufactured by Kett Science Laboratory Co., Ltd.). This moisture meter measures the amount of moisture in contact with the concrete surface. In addition, the measured value of the moisture content in a present Example is an average moisture content from the surface of concrete to the depth of about 10-40 mm in general.

The cement used is the following cement.

Ordinary Portland cement (Sumitomo Osaka Cement)
Early strong Portland cement (manufactured by Sumitomo Osaka Cement)
Super early polymer cement (BASF Master Emmaco S123)
Fast-hardening cement (Master Top 561, BASF Corporation)
Fast-hardening cement (no shrinkage) (Hi-Pretuscon TYPE-H manufactured by Denki Kagaku Kogyo Co., Ltd.)

Each layer of the acid resistant layer was formed of the following materials.
In addition, the topcoat layer formed two layers with the same material.

(Primer layer)
Main agent: Epoxy resin (available from Arrow Chemical Co., Ltd., product name: Arrow Resin H-110N)
Curing agent: Modified aromatic polyamine (Kyodo Pharmaceutical Co., Ltd. product name: ML-2)
Mixing ratio (weight ratio): Main agent 10: Curing agent 1

(Resin mortar layer)
Main agent: Epoxy resin (available from Arrow Chemical Co., Ltd., product name: Arrow Resin H-110N)
Curing agent: Tritetraamine (Product name: Arrow Resin H-110N, manufactured by Arrow Chemical Co., Ltd.)
Silica sand mixing ratio (weight ratio): Main agent 10: Hardener 1: Silica sand 50

(Topcoat layer)
Main agent: Epoxy resin (available from Arrow Chemical Co., Ltd., product name: Arrow Resin H-110N)
Curing agent: Tritetraamine (Product name: Arrow Resin H-110N, manufactured by Arrow Chemical Co., Ltd.)
Glass powder colored powder: Fujimi Incorporated blending ratio (weight ratio): Main agent 10: Curing agent 1: Glass powder 0.8: Color powder 0.6

The results are shown in FIG.
As shown in FIG. 3, when the acid-resistant layer is formed in a state where the moisture content of the concrete base is 8% or more, the peel strength is lower than 1.0 N / mm ² in all cases. On the other hand, when the acid-resistant layer was formed with a moisture content of 8% or less, the peel strength was 1.0 N / mm ² or more except for 4 cases out of 18 cases. When the acid-resistant layer is formed with a moisture content of 6.5% or less, the peel strength is 1.0 N / mm ² or more except for 3 cases out of 16 cases, and the peel strength is 1 except for 6 cases. 0.5 N / mm ² or more. In particular, when the moisture content is 6.5% or less, the fast-curing cement has a peel strength of 1.0 N / mm ² or more except for one case out of 10 cases, and a peel strength of 1.5 N except for 2 cases. / Mm ² or more. In the case of rapid-cement-free shrinkage, all cases in peel strength becomes 1.5 N / mm ² or more, except for one case, the peel strength became 2.0 N / mm ² or more.

  From the above results, it was confirmed that the peel strength can be increased to a level that does not cause a practical problem by setting the moisture content of the concrete base to 8% or less, particularly 6.5% or less. And it was confirmed that the non-shrinkage and low-shrinkage fast-hardening cement tends to increase the peel strength.

(Influence of surface treatment)
In the above experiment, by the water content of 8% or less, peel strength becomes 1.0 N / mm ² or more, by 6.5% or less, the peel strength is 1.5 N / mm ² or more Was confirmed.

  On the other hand, when the moisture content was 8% or less, it was confirmed that there was a difference in peel strength even with the same cement and moisture content. In the above experiment, since the surface of the ground concrete was not specially treated, it was considered that the surface properties may have affected the peel strength.

  Therefore, before the acid-resistant layer was formed, the surface of the concrete base was treated, and the effect of the treatment on the peel strength was confirmed.

  The concrete base was formed of ordinary Portland cement and early-strength Portland cement, which had low strength in the above examples, and was subjected to surface treatment after the water content became 5% or less.

The surface treatment was performed by the following four methods.
(1) Wiping with a wet cloth (2) Cleaning with a vacuum cleaner (3) Cleaning with a wire brush
(4) Polishing with a polishing device + Finishing treatment with sandpaper + Sweep cleaning (using wire brush)
For polishing, a polishing apparatus manufactured by LINAX Corporation was used.
Also, sandpaper # 30 (manufactured by Sumitomo 3M) was used.

The results are shown in FIG.
In addition, in FIG. 4, what is surrounded by a circle | round | yen is a thing whose peel strength is 1.5 N / mm < ² > or less. Of those having a peel strength of 1.5 N / mm ² or more, those surrounded by a square are those that have undergone interfacial peeling, and others that have undergone ground breaking.

As shown in FIG. 4, in (1) wiping with a wet cloth, the peel strength could be 1.0 N / mm ² or more, but in most cases the peel strength was 1.0 N / mm ² or less. It was. On the other hand, in other processes, except for one case, the peel strength is 1.5 N / mm ² or more.

  When cleaning with a wet cloth, the frictional force applied to the concrete surface is small, but with other treatments, a certain amount of frictional force (for example, a frictional force that can remove weak unevenness and latency on the concrete ground surface) is applied to the concrete ground. It is thought that it has joined the surface.

  Therefore, it was confirmed that the peel strength can be increased by rubbing the surface of the concrete base so that a frictional force of a certain level or more is generated, or by scraping or polishing the surface. In other words, it was confirmed that the peel strength can be increased by performing the above-described treatment on the surface even if the concrete base has a low peel strength when nothing is treated.

  The method for constructing an acid-resistant floor according to the present invention is suitable as a method for imparting acid resistance to a floor where an electrolytic bath for copper electrolytic smelting is installed, indoor / outdoor scenes where an acidic liquid flows out, a breakwater, and the like.

DESCRIPTION OF SYMBOLS 1 Acid-resistant floor 2 Concrete base 2a Concrete base surface 5 Acid-resistant layer 6 Primer layer 7 Resin mortar layer 8 Topcoat layer 10 Repair floor part 30 Sealing agent

Claims (13)

An acid-resistant floor construction method in which an acid-resistant layer is formed on the surface of a concrete base,
A method for constructing an acid-resistant floor, characterized in that a coating agent made of epoxy resin is applied to the surface of a concrete foundation after the moisture content of the placed concrete foundation is 8% or less. The construction of an acid-resistant floor according to claim 1, wherein a coating agent made of an epoxy resin is applied to the surface of the concrete base after the moisture content of the placed concrete base becomes 6.5% or less. Method. The method for constructing an acid-resistant floor according to claim 1 or 2, wherein the surface of the concrete base is rubbed before applying the coating agent. 4. The method for constructing an acid resistant floor according to claim 3, wherein the surface of the concrete base is rubbed with a force capable of removing the latency existing on the surface of the concrete base. The method for constructing an acid-resistant floor according to claim 4, wherein the surface of the concrete base is polished. 6. The method for constructing an acid-resistant floor according to claim 1, wherein the concrete base is made of a fast-hardening cement. The method for constructing an acid-resistant floor according to claim 6, wherein the fast-hardening cement is non-shrinkage or low-shrinkage cement mortar. A floor in which an acid-resistant layer is formed on the surface of a concrete floor,
Concrete foundation,
An acid-resistant floor comprising an acid-resistant layer formed on the surface of the concrete base by applying a coating agent made of an epoxy resin in a state where the moisture content of the concrete base is 8% or less. The acid resistant layer is
9. The acid-resistant floor according to claim 8, wherein the concrete-coated floor is formed by coating with a moisture content of 6.5% or less. The acid-resistant floor according to claim 8 or 9, wherein a peel strength of the acid-resistant layer is 1.5 N / mm ² or more. The acid-resistant floor according to claim 8, 9 or 10, which is formed by the method according to any one of claims 1 to 7. A method for repairing an acid-resistant floor in which an acid-resistant layer is formed on the surface of a concrete floor,
A removal step of removing the acid-resistant layer at the repair site and the surface portion of the concrete floor at the repair site;
A spacer is arranged at the boundary between the removed portion formed by removing the acid-resistant layer and the surface portion of the concrete floor by the removal step and the existing portion of the acid-resistant floor, and concrete is placed in the removed portion for repair. A placing process for forming a concrete base;
An acid resistant layer forming step of forming a repaired acid resistant layer on the surface of the repaired concrete foundation cast in the casting step to form a repair floor portion;
After the repair acid-resistant layer is formed by the acid-resistant layer forming step, the spacer is removed, and the space formed by removing the spacer is filled with a sealant having elasticity. How to repair sexual floors. The method for repairing an acid-resistant floor according to claim 12, wherein the repair floor is formed by the method according to any one of claims 1 to 7.

Images