KR102000102B1 - A permeable high-strength smart concrete composition, preparation method thereof and high-strength smart articles prepared with the same - Google Patents

Abstract

The present invention relates to a permeable concrete composition having not only excellent permeability but significantly improved strength such as compression strength, bending strength or the like and having smart functions such as rapid repairing and reinforcement, collection of data, heating or the like, to a preparation method thereof, and to a permeable concrete article prepared thereby. The permeable concrete composition comprises aggregate and a binder containing cement, blast furnace slag, silica fume, silica powder, water and a water reducing agent.

Description

TECHNICAL FIELD [0001] The present invention relates to a high strength smart permeable concrete composition, a method of manufacturing the same, and a high strength smart permeable concrete product manufactured from the same. BACKGROUND OF THE INVENTION 1. Field of the Invention [0001]

The present invention relates to a high strength smart permeable concrete composition, a method for producing the same, and a high strength smart permeable concrete product manufactured therefrom. More particularly, the present invention relates to a high-strength smart permeable concrete composition having a strength such as excellent permeability and remarkably improved compressive strength and bending strength, and further imparting smart functions such as rapid maintenance and data collection, And a high strength smart pitching concrete product manufactured therefrom.

Concrete, which is a mixture of aggregate, cement and water, is mainly used for flooring such as roads. Concrete is formed by hardening or solidifying, and has a more robust structure over time. This prevents the infiltration of water and air, and causes water to condense on the concrete surface, which requires a separate drainage means.

Thus, a permeable concrete having a plurality of voids formed therein so as to be permeable to water or air is used.

The permeable concrete enables the permeation of water and air by forming a gap between the aggregate and the aggregate. Rainwater or water passes through concrete and permeates into the ground, preventing water from reaching the roads and sidewalks.

However, there is a problem that strength of the concrete such as compressive strength and bending strength is lowered by the internal void. Further, when the moisture in the inner cavity is frozen, cracks or surface peeling due to the expansion pressure may occur, and the durability may be greatly reduced.

Therefore, there is a demand for a technique of permeable concrete having excellent strength such as compressive strength and bending strength while securing permeability.

Concrete, on the other hand, aging and deteriorating performance after a certain period of time after casting or molding, requires maintenance such as repair or reinforcement. Particularly, it is important to control cracks because cracks in concrete can facilitate penetration of harmful substances into the inside of the concrete, thereby accelerating the deterioration of performance. A technique for self-healing concrete has been proposed in this way.

Self-healing concrete technology uses components such as swelling agent, expanding agent or carbonating agent to swell by the reaction with water, to restore crack through expansion, or to make carbon dioxide penetrate carbonation reaction with carbonating agent more tightly . This is because it restores and heals the cracked concrete itself, so there is no need to repair it further, and maintenance cost can be saved by extending the use period of concrete. However, the swelling agent and swelling agent applied to the self-healing concrete technique are expensive and uneconomical, and there is a problem that the initial strength of the concrete is lowered at the early stage of the casting.

Korean Patent No. 10-1214596 (December 14, 2012) Korean Patent No. 10-1303622 (Aug. 29, 2013)

It is an object of the present invention to provide a high strength smart permeable concrete composition capable of shortening a curing time and stably maintaining strength after an initial curing for a long period of time.

It is another object of the present invention to provide a high strength smart permeable concrete composition having excellent water permeability and remarkably improved strength.

Another object of the present invention is to provide a high-strength smart permeable concrete composition having excellent compression-freezing resistance.

It is another object of the present invention to provide a concrete structure which can detect a deformation or damage of a structural member and can quickly repair and reinforce it, and can prevent accelerating degradation due to cracking, Strength concrete pervious concrete product that can collect and respond to data.

It is another object of the present invention to provide a high-strength smart permeable concrete product capable of generating an electromotive force by using a change in electric resistance to store energy, and further enabling heat generation by itself.

In order to accomplish the above object, one aspect of the present invention is an aggregate comprising: an aggregate (A); And a binder (B) containing cement, blast furnace slag, silica fume, silica powder, water and a water reducing agent, wherein the weight ratio of the aggregate (A) and the binder (B) is from 1.5: 1 to 3.0: And to provide a smart permeable concrete composition.

In the high strength smart permeable concrete composition according to one embodiment of the present invention, the binder (B) is a mixture of 10 to 40 parts by weight of silica fume, 10 to 40 parts by weight of silica powder, 10 to 30 parts by weight of water and 1 to 10 parts by weight of a water reducing agent.

In the high strength smart permeable concrete composition according to an embodiment of the present invention, the mixture of cement and blast furnace slag may be 65 to 95 wt% of cement and 5 to 35 wt% of blast furnace slag.

In the high-strength smart permeable concrete composition according to an embodiment of the present invention, the aggregate (A) may include a fine aggregate having a particle size of 2.5 to 6.0 mm.

In the high-strength smart permeable concrete composition according to an embodiment of the present invention, the silica fume may have an average particle diameter of 0.01 to 1.0 탆.

In the high-strength smart permeable concrete composition according to an embodiment of the present invention, the silica powder may have an average particle size of 1.2 to 2.5 占 퐉.

In the high-strength smart permeable concrete composition according to an embodiment of the present invention, the water reducing agent may be any one or more high-performance water reducing agents selected from the group consisting of a polycarboxylic acid compound, a naphthalene compound and a lignin compound.

In the high-strength smart permeable concrete composition according to an embodiment of the present invention, the binder may further include a carbon-based conductive filler.

In the high-strength smart permeable concrete composition according to an embodiment of the present invention, the carbon-based conductive filler may include at least one selected from carbon black, carbon fiber, carbon nanowire, and mixtures thereof.

Another aspect of the present invention relates to a method of manufacturing an aggregate; And a binder containing cement, blast furnace slag, silica fume, silica powder, water, a water reducing agent and a carbon-based conductive filler, wherein the weight ratio of the aggregate and the binder is 1.5: 1 to 3.0: 1. To provide a smart permeable concrete product.

The smart permeable concrete product according to an embodiment of the present invention is characterized in that the smart permeable concrete product satisfies the following formula 1 in Fractional Change in Resistivity (FCR) measured according to ASTM-G57 .

[Formula 1]

(In the above equation 1, ρ ₀ is an initial electrical resistivity value not under load, and ρ _x is an electrical resistivity value with respect to a maximum tensile load measured when a load is applied.)

The high strength smart permeable concrete product according to an embodiment of the present invention may have a sensing application for sensing external force.

The high strength smart permeable concrete product according to an embodiment of the present invention may have self-heating purpose.

Still another aspect of the present invention is a method for producing a composite material, comprising the steps of: a) preparing a binder containing cement, blast furnace slag, silica fume, silica powder, water reducing agent and water, and b) mixing an aggregate containing the binder and the fine aggregate And mixing the aggregates at a weight ratio of 1.5 to 3.0 based on the weight of the binder to provide a method of manufacturing a high strength smart permeable concrete composition.

In the method of manufacturing a high-strength smart permeable concrete composition according to an embodiment of the present invention, the binder may further include a carbon-based conductive filler.

In the method of manufacturing a high-strength smart permeable concrete composition according to an embodiment of the present invention, the carbon-based conductive filler may be dispersed by mixing the carbon-based conductive filler with water, And mixing with other components.

In the method of manufacturing a high strength smart permeable concrete composition according to an embodiment of the present invention, the binder may include 10 to 40 parts by weight of silica fume, 10 to 40 parts by weight of silica powder, 10 to 30 parts by weight of water and 1 to 10 parts by weight of a water reducing agent.

In the method of manufacturing a high strength smart permeable concrete composition according to an embodiment of the present invention, the mixture of cement and blast furnace slag may be composed of 70 to 90% by weight of cement and 10 to 30% by weight of blast furnace slag.

The present invention has an advantage that early strength can be ensured despite shortened curing time, and excellent strength can be maintained for a long time even after curing. It is possible to provide a high strength smart permeable concrete composition capable of realizing significantly improved compressive strength and bending strength at the same time as permeability.

Further, the present invention has an advantage of excellent compression-freezing resistance.

Furthermore, the present invention has the advantage of providing a high-strength smart permeable concrete product that can detect rapid deformation or damage of the structural member, thereby enabling quick repair and reinforcement, and preventing acceleration of performance deterioration due to cracks.

In addition, the present invention can detect a situation occurring through the concrete and collect data according to the detected situation. Also, it is possible to store energy by generating an electromotive force by using a change in electric resistance, and it has an advantage that heat can be generated by utilizing it.

Hereinafter, a high strength smart permeable concrete composition of the present invention, a method for producing the same, and a high strength smart permeable concrete product manufactured therefrom will be described in detail. The present invention can be better understood by the following embodiments. The following aspects are for the purpose of illustrating the present invention and are not intended to limit the scope of protection defined by the appended claims. The technical terms and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the art to which the present invention belongs, unless otherwise defined.

The terms used in the description of the present invention are merely for the purpose of effectively describing certain embodiments. It is also to be understood that the singular forms as used in the specification and the appended claims are intended to include the plural forms as well, unless the context clearly indicates otherwise.

The inventors of the present invention have intensified their studies on permeability concrete compositions having improved permeability and strength such as compressive strength and bending strength and found that the combination of components including cement, blast furnace slag, silica fume and silica particles, combinations of these components And a carbon-based conductive filler to be added to the binder to ensure the initial strength of the permeable concrete, as well as to realize a high permeability coefficient and remarkably improved compressive strength and bending strength, It was confirmed that it has a melting resistance. Further, it is possible to collect and respond to data by sensing rapid repair and reinforcement and load by sensing the deformation of the structural member, storing the energy by using the rate of change of electric resistance generated, and as a self- Performance can be realized, and the present invention has been completed.

Hereinafter, the high-strength smart permeable concrete composition according to the present invention will be described in detail.

One aspect of the present invention relates to an aggregate (A); And a binder (B) containing cement, blast furnace slag, silica fume, silica powder, water and a water reducing agent.

The weight ratio of the aggregate (A) and the binder (B) is 1.5: 1 to 3.0: 1. The mixing weight ratio of the aggregate (A) and the binder (B) may be specifically 1.7 to 2.8, more specifically 1.5 to 2.5. It is possible to secure high water permeability and strength at the same time, shortening the curing time and securing long-term property stability in the above-mentioned range, but this is a non-limiting example and is not limited to the above numerical range.

According to one aspect of the present invention, the aggregate may be conventional aggregates used in the art, and the kind thereof is not particularly limited, but specifically includes fine aggregates.

The fine aggregate may have a particle size of 2.5 to 6.0 mm, specifically 3.0 to 5.5 mm, more specifically 3.5 to 5.0 mm. As a concrete example, it may be fine aggregate such as sand passing through a sieve having a size of 6.0 mm. Further, the unit weight may be 2.0 to 3.0 g / cm3, specifically 2.2 to 2.8 g / cm3, but is not limited thereto. In the above range, it is effective in combination with other components in the composition in terms of excellent water permeability and simultaneously strength improvement such as compressive strength and bending strength, but this is only a non-limiting example and is not limited to the above numerical range.

The aggregate may include a coarse aggregate at the same time as the fine aggregate. The ratio of the fine aggregate to the coarse aggregate may be 80:20 to 95: 5, specifically 85:15 to 90:10, but is not limited thereto. The use of the combination of the fine aggregate and the coarse aggregate may be more effective in securing high water permeability and improving freeze-thaw resistance.

The coarse aggregate has a relatively large particle size as compared with fine aggregate, and is an aggregate that can not pass through a sieve having a size of 6 mm. The maximum size of the coarse aggregate is preferably 25 mm.

The permeable concrete composition according to an embodiment of the present invention includes a binder having a combination of specific components simultaneously with the aggregate. The binder is characterized by containing cement, blast furnace slag, silica fume, silica powder, water and a water reducing agent.

The cement is a mixture of the calcareous raw material and the clay raw material, and includes Portland cement. Specifically, the Portland cement may be, but is not necessarily limited to, meeting the type I criteria set forth in ASTM C150.

The above-mentioned ground granulated blast furnace slag (GGBS) is a by-product obtained in the manufacture of pig iron in a blast furnace, and is used to partially replace the cement in terms of environment and economy.

Although the mixing weight ratio of the cement and the blast furnace slag is not particularly limited, the cement may be 65 to 95% by weight, specifically 70 to 90% by weight, more specifically 72 to 88% by weight in terms of improving the compressive strength and the bending strength , The blast furnace slag may be 5 to 35% by weight, specifically 10 to 30% by weight, more specifically 12 to 28% by weight, but not always limited thereto.

The silica fume can enhance the compressive strength and the bending strength according to the pore filling effect from the initial stage of hydration by pozzolanic reaction.

The average particle diameter of the silica fume is not particularly limited, but may be 0.01 to 1.0 탆, specifically 0.1 to 0.8 탆. In the above range, excellent effects are obtained in combination with other components in the composition in terms of enhanced strength, shortening of curing time and securing initial strength, but this is a non-limiting example and is not limited to the above numerical range.

The silica fume may be contained in an amount of 10 to 40 parts by weight, specifically 15 to 35 parts by weight, more specifically 20 to 30 parts by weight, based on 100 parts by weight of the mixture, based on the content of the mixture of the cement and the blast furnace slag, But is not limited thereto.

In addition, the silica fume is more effective in that it can be uniformly dispersed in the composition in combination with a carbon-based conductive filler, particularly a carbon fiber having a high aspect ratio, among the additive components described later. Specifically, the combination of the constituent components improves the sensing performance of the smart concrete product by further increasing the rate of change of electrical resistance through securing of the conductive network, and is more effective in terms of energy storage and self-heating performance due to variation of electrical resistance.

The silica fume is used in combination with silica powder. This is more effective in achieving the intended properties of the present invention. Concretely, by using with other components in the composition at the same time, it has an effect of not only ensuring initial strength but also remarkably improving strength such as compressive strength and flexural strength.

The average particle diameter of the silica powder is not particularly limited, but may be 1.2 to 2.5 占 퐉, specifically, 1.5 to 2.0 占 퐉, but the present invention is not limited thereto.

The silica powder may include 10 to 40 parts by weight, specifically 15 to 35 parts by weight, more specifically 20 to 30 parts by weight, based on 100 parts by weight of the mixture of the cement and the blast furnace slag, but is not limited thereto.

The water reducing agent may be any one or more high performance water reducing agents selected from the group consisting of polycarboxylic acid compounds, naphthalene compounds and lignin compounds, but is not limited thereto. Specifically, it may be a polycarboxylic acid-based compound. The polycarboxylic acid-based compound is more effective in terms of ensuring high water permeability, and in view of achieving excellent conductivity expressed in combination with a carbon-based conductive filler contained in the production of a smart water permeable concrete product described later.

The water reducing agent may include 1 to 10 parts by weight, specifically 2 to 8 parts by weight, more specifically 3 to 5 parts by weight, based on 100 parts by weight of the mixture of cement and blast furnace slag, but is not limited thereto.

The water content is not particularly limited, but may be 10 to 30 parts by weight, specifically 15 to 25 parts by weight based on 100 parts by weight of the mixture of cement and blast furnace slag. The above range is effective in facilitating the incorporation of components in the composition and realizing uniform property and strength improvement of the produced concrete product, but this is a non-limiting example and is not limited to the above numerical range.

According to one aspect of the present invention, the binder may further include a carbon-based conductive filler. This makes it possible to form a conductive network structure inside the concrete. In addition, such a conductive network can realize a synergistic effect of lowering the water content and increasing the permeability due to the hydrophobicity of the surface. Further, it is possible to detect various changes such as compression, tensile, flexure, and load generated in the concrete structure by making it possible to detect a change in electrical resistance. Structural deformation and load detection are more effective in preventing acceleration of degradation due to cracking, enabling quick repair and reinforcement, and collecting various data.

The carbon-based conductive filler can be used without limitation as long as it can form an efficient conductive network in a concrete structure. But is not limited to, any one or more selected from carbon black, carbon fiber, carbon nanowire, and mixtures thereof. At this time, the carbon nanowires may include carbon nanotubes.

The carbon-based conductive filler may have a high aspect ratio, but is not necessarily limited thereto. Specifically, the carbon fiber may have an aspect ratio of 100 to 50,000, specifically 500 to 40,000. Further, the length may be 0.01 to 1,000 탆, specifically 0.1 to 900 탆. The effect of imparting a high conductivity at a low content in the above range is only a non-limiting example and is not limited to the above range of values.

The carbon black may have a BET surface area of 100 to 150 (m < 2 > / g) and an average particle diameter of 20 to 100 mu m, specifically 30 to 80 mu m.

The carbon-based conductive filler may more preferably comprise a combination of carbon black and carbon fibers or carbon black and carbon nanowires. This is more effective in terms of achieving a synergistic effect of compressive strength and bending strength at the same time as conductivity. At this time, it is more effective that the content of the carbon fibers or carbon nanowires mixed with the carbon black is 1 to 4 times, more preferably 1.5 to 3.0 times as much as the carbon black.

The carbon-based conductive filler may be added in an amount of 0.1 to 10 parts by weight, specifically 0.5 to 8 parts by weight, more preferably 1 to 6 parts by weight, based on 100 parts by weight of the mixture of cement and blast furnace slag. In this range, excellent conductivity and strength can be maintained while excellent conductivity can be imparted, but this is a non-limiting example and is not limited to the above numerical range.

The carbon-based conductive filler is more effective in preventing deterioration of physical properties such as cracking and durability of concrete due to corrosion compared to metal fibers, and is particularly superior in water permeability and compression strength increasing effect.

The binder may include an elastomer at the same time as the carbon-based conductive filler. By including such a combination of components, it is possible to further improve the detection performance of deformation, load change, etc. in the concrete structure. By giving elasticity specifically, it has an excellent effect in terms of facilitating compression deformation and maximizing change in electric resistance.

The elastomer can be used without limitation as long as the conductive network structure formed by the carbon-based conductive filler in the composition is not inhibited and has excellent elasticity within a range in which the strength is not weakened so that the structure is excellent in deformation and recovery. Specific examples include styrene-butylene-styrene (SBS) block copolymers, styrene-isoprene-styrene (SIS) block copolymers, and styrene-ethylene-butylene-styrene However, the present invention is not limited thereto.

The content of the elastomer is not particularly limited so far as it does not impair the object of the present invention, but may be 2 to 30 parts by weight, specifically 5 to 20 parts by weight, based on 100 parts by weight of the mixture of cement and blast furnace slag .

If the binder comprises a carbon-based conductive filler, it may simultaneously contain a surfactant. The surfactant can be used without limitation as long as it can increase the dispersibility in the concrete structure of the carbon-based conductive filler. As a non-limiting example, surfactants such as nonionic surfactants, anionic surfactants, cationic surfactants and amphoteric surfactants can be used. As one specific example, it may include, but is not limited to, polyvinyl alcohol, polyvinyl pyrrolidone, carboxymethyl cellulose, polyethylene oxide, and the like.

The content of the surfactant is not particularly limited so far as it does not impair the object of the present invention, but may be 2 to 15 parts by weight, specifically 5 to 10 parts by weight, based on 100 parts by weight of the mixture of cement and blast furnace slag.

It will be appreciated that the binder may in other embodiments comprise a combination of a carbon-based conductive filler, an elastomer, and a surfactant.

Another aspect of the present invention relates to a method of manufacturing an aggregate; And a binder containing cement, blast furnace slag, silica fume, silica powder, water, a water reducing agent and a carbon-based conductive filler.

The smart pitcher concrete product is characterized in that the weight ratio of the aggregate and the binder is in the range of 1.5: 1 to 3.0: 1, specifically 1.7 to 2.8, more specifically 1.5 to 2.5. It has the characteristics of excellent strength such as compressive strength and bending strength at the same time as permeability.

The smart permeable concrete product according to an embodiment of the present invention preferably has a fractional change in resistivity (FCR) of the following formula (1).

[Formula 1]

(In the above formula 1, rho 0 is an initial electric resistivity value not under load, and rx is an electric resistivity value measured when a load is applied.)

Generally, the electrical resistance of the concrete material is measured in Ohm, but the concept of electrical resistivity is used to take into account the influence of the measured area and distance. The electrical resistivity is closely related to the microstructure of the concrete as shown in Equation (1), and it is generally known that the concrete having a smaller void content has a higher electrical resistance.

In addition, cementitious materials through electrical resistance must include conductive materials in order to have self-sensing ability, and conductive elements serve as an electrical connection in the structure, so that when the damage or deformation is applied in the structure, the electrical resistivity Change. Generally, it is known that the damage detection ability of cementitious composite materials including carbon-based materials is excellent.

In particular, the smart permeable concrete product can cause a change in electrical resistance due to compressive cyclic loading. It detects deformations or cracks, and allows the user to collect data on the source of external forces applied to the product or damage to the product. That is, the detected information is grasped through a separate collecting device, so that follow-up measures can be taken.

In a specific embodiment, the smart permeable concrete product has a sensing purpose of collecting data through measurement of the rate of change of electrical resistance from an external force applied, for example, compression, tensile, flexure, load, In a more specific and non-limiting example, the smart pitcher concrete product is a smart sidewalk block in which a rate of change in electrical resistance is measured as the load is transmitted, and the vehicle is parked on the block via a separate sensing device associated with the sidewalk block And the like. This makes it possible to utilize the data such as securing the parking data of the vehicle and confirming illegal parking. It is possible to grasp the passage of pedestrians as well as the vehicle, and it has an advantage that it can be applied to various fields applied to prevent the entry of the power means in addition to the bicycle on the bicycle road.

Further, by providing a control device associated with such a sidewalk block, it is possible to operate an illumination device such as an LED when a walk is detected. This is effective for energy saving.

Another aspect of the smart permeable concrete product is that it has a self heating application. If the electric resistance is changed by the load applied to the upper part of the concrete, electricity can be flowed so that the heat can be generated. These self-heating smart permeable concrete products can effectively prevent concrete structure from being damaged due to freezing of the surface of the concrete or cooling of the infiltrated water during the winter season.

In addition, the electromotive force can be generated by the temperature difference of the electrical resistance of the concrete, and thus it can be stored as electric energy. The stored electrical energy can be supplied to the concrete to be reheated itself.

The smart water permeable concrete product may be applied to various fields other than the above-mentioned aspects.

Another aspect of the present invention includes a process for producing a binder containing a) a cement, a blast furnace slag, a silica fume, a silica powder, a water reducing agent and water, and b) mixing an aggregate containing the binder and the fine aggregate The present invention relates to a method for producing a water permeable concrete composition.

At this time, the aggregate is mixed at a ratio of 1.5 to 3.0 weight ratio of the binder.

The binder may further include a carbon-based conductive filler.

When the binder further comprises a carbon-based conductive filler, the carbon-based conductive filler is mixed with water and dispersed in an aqueous dispersion in which the carbon-based conductive filler is dispersed through a high-speed stirring means such as a homogenizer And then mixed with silica fume, followed by mixing with other components in the composition. This is more effective in terms of excellent dispersibility and uniformity of physical properties of the concrete product.

When the binder further comprises an elastomer in addition to the carbon-based conductive filler, an aqueous dispersion in which the carbon-based conductive filler is dispersed is mixed with the mixture of the elastomer and silica fume, mixed with other components in the composition, .

Further, the binder may further comprise a surfactant at the same time as the carbon-based conductive filler. In this case, it is more effective in achieving the desired physical properties of the invention to mix the silica fume with the aqueous dispersion in which the carbon-based conductive filler is dispersed, then add the surfactant, and then mix it with other components in the composition.

The binder may, in another embodiment, simultaneously contain a carbon-based conductive filler, an elastomer, and a surfactant. In this case, a mixture of an elastomer and silica fume is put into an aqueous dispersion in which the carbon-based conductive filler is dispersed, May be mixed with other components in the composition, but the present invention is not limited thereto.

According to one embodiment of the present invention, the binder is a mixture of 10 to 40 parts by weight of silica fume, 10 to 40 parts by weight of silica powder, 10 to 30 parts by weight of water and 1 to 10 parts by weight of water reducing agent per 100 parts by weight of the mixture of cement and blast- Parts by weight.

In addition, the mixture of the cement and the blast furnace slag may be 70 to 90% by weight of cement and 10 to 30% by weight of blast furnace slag.

Hereinafter, an example of a permeable concrete composition according to the present invention and a smart permeable concrete product manufactured from the permeable concrete composition will be described. The following examples are illustrative of the present invention and are not intended to limit the scope of the present invention.

(Example 1)

The water permeable concrete composition was prepared according to the composition of the following Table 1 (content: parts by weight).

Specifically, with respect to 100 parts by weight of a mixture consisting of 80% by weight of type I Portland cement (C3A 5 wt%, 3930 cm2 / g Blaine value) and 20% by weight of blast furnace slag (CGBS) specified in ASTM C150, silica fume , 25 parts by weight of silica particles (average particle diameter 1.7 mu m), 22 parts by weight of water (H ₂ O) and 25 parts by weight of polycarboxylate ether (FLOWMIX 3000 U, Southeast Enterprise) were mixed to produce a binder.

The weight ratio of the prepared binder to fine aggregate (4.5 to 5.5 mm, yield ratio of 61.2%, porosity of 38.8%) was 1: 2.5 and mixed to prepare a water permeable concrete composition. The mixing was carried out in the following manner. First, a mix of concrete was used in a 20 liter Horbart type mixer. The order of mixing was cement, blast furnace slag, silica fume, and silica powder, and dried for 90 seconds. Half of the weighed water was added and mixed for 60 seconds, then the remaining water was added and stirring was continued for 60 seconds. In the case of carbon materials, when the water is put, the carbon material is put into water so that the material can be loosened well and then put together. After the addition of water reducing agent, if the mortar showed sufficient fluidity, add the aggregate and mix for 180 seconds. Then, after pouring into the mold, the specimen was covered with vinyl and stored at room temperature. After 24 hours, the specimen was desolvated in a completely hardened state, and the experiment was conducted after curing.

(Example 2)

A water permeable concrete composition was prepared in the same manner as in Example 1, except that the content of cement and blast furnace slag was changed to 95 parts by weight and 5 parts by weight, respectively, in Example 1.

(Example 3)

A permeable concrete composition was prepared in the same manner as in Example 1, except that the content of cement and blast furnace slag was changed to 70 parts by weight and 30 parts by weight, respectively, in Example 1.

(Example 4)

The carbon black (Carbon Black, CB, Ketjenblack EC300J, specific surface area 800 m2 / g) was mixed with the blend 100 of cement blast furnace slag in the same manner as in Example 1 except that the content of cement and blast furnace slag was changed to 76.8 parts by weight and 20 parts by weight, A water permeable concrete composition was prepared in the same manner as in Example 1, except that 3.2 parts by weight was further added.

(Example 5)

(Carbon fiber, GNF-100 (herringbon type), carbon nanotec) were changed to 74.4 parts by weight and 20 parts by weight, respectively, in the cement and blast furnace slag in Example 1, Was further added in an amount of 5.6 parts by weight based on 100 parts by weight of the cement blast furnace slag mixture to prepare a water permeable concrete composition.

(Example 6)

In Example 1, the content of cement and blast furnace slag was changed to 75 parts by weight and 20 parts by weight, respectively, and 2.0 parts by weight and 3.0 parts by weight of carbon black and carbon fiber were added to 100 parts by weight of the mixture of cement blast furnace slag The procedure of Example 1 was repeated to prepare a water permeable concrete composition.

(Example 7)

Same as Example 6 except that the content of cement was changed from 75 parts by weight to 74 parts by weight in Example 6 and 1.0 part by weight of carboxymethylcellulose (CMC) was added based on 100 parts by weight of the mixture of cement blast furnace slag To prepare a water permeable concrete composition.

(Comparative Example 1)

In Example 1, a water permeable concrete composition was prepared in the same manner as in Example 1, except that silica particles were not included.

(Comparative Example 2)

In Example 1, a permeable concrete composition was prepared in the same manner as in Example 1, except that silica fume was not included.

(Comparative Example 3)

A permeable concrete composition was prepared in the same manner as in Example 1, except that the weight ratio of aggregate and binder in Example 1 was changed from 2.5 to 1.4.

[Table 1]

(evaluation)

(1) Compressive Strength (MPa): The compressive strength was measured according to KS F 2405 for the specimens of the waterproof concrete compositions of Examples and Comparative Examples, and the results are shown in Table 2 below.

(2) Flexural Strength (MPa): The specimens of the permeable concrete compositions of Examples and Comparative Examples were measured for bending strength according to KS F 2408, and the results are shown in Table 2 below.

(3) Permeability Coefficient: The permeability coefficient was measured according to KS F 4419 for the specimens of the permeable concrete compositions of Examples and Comparative Examples, and the results are shown in Table 2 below.

(4) Freeze-thaw resistance: Freeze-thaw resistance was evaluated according to the resistance test method of concrete against rapid freezing and thawing of KS F 2456 in the test pieces of the permeable concrete compositions of Examples and Comparative Examples. The results are shown in Table 1. The results are shown in Table 1. The results are shown in Table 1. The results are shown in Table 1. The results are shown in Table 1. The results are shown in Table 1. [ If the percentage is less than 40%, the symbol is marked with " DELTA "

(5) Resistance change rate: Electrical resistance was measured according to ASTM G57 (Wenner 4 electrode method), and the equipment used was a 4-probe method using a multimeter (Keysight 3458A Multimeter, Keysight Technologies, USA) . As a result, the FCR (Fractional Change in Resistivity) value was shown.

Specifically, a dumbbell-type test piece having a width of 50 mm and a thickness of 50 mm was used as a test sample for the direct tensile test to measure the electrical resistance. In order to measure the elongation of the specimen, the displacement measurement range was limited to 50mm. To prevent damage and cracking outside the measuring range, the steel wire mesh was reinforced at both ends of the tensile test specimen. All the specimens were wet cured at 24 ° for 14 days. The electrical resistance was measured by a 4-probe resistivity method using a multimeter. Copper tape was used for the inner and outer electrodes, and silver paste was applied to the surface of the test piece, and a copper tape was attached thereon. The distance between the two external electrodes flowing the direct current of the input current (5 μA) is 110 mm, and the two internal electrodes measuring the voltage are located 30 mm inward from the external electrode for current.

The static tensile test was carried out using a universal testing machine (UTM) with a maximum load capacity of 5 tons. The displacement was measured at a speed of 1 mm / min by installing two LVDTs on both sides of the specimen. The results are shown in Table 2 below.

[Table 2]

As shown in Table 2, the examples exhibited excellent strength such as compressive strength and bending strength, high water permeability coefficient and excellent freeze-thaw resistance throughout the physical properties. Further, Examples 4 to 7 showed that the resistance to freezing and thawing was drastically improved, and the rate of change in electrical resistance was very high, and it was confirmed that the applicability to various fields as a smart permeable concrete product could be expected.

On the other hand, the strengths of the comparative examples were lower than those of the examples. In particular, the flexural strength was lowered much more and the characteristics of freeze-thaw resistance were significantly lower than those of the examples. In addition, from the comparative examples, it is impossible to measure the change of electric resistance as in Examples 4 to 7, and the use thereof can not be expected at all.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, Various modifications and variations are possible in light of the above teachings.

Accordingly, the spirit of the present invention should not be construed as being limited to the embodiments described, and all of the equivalents or equivalents of the claims, as well as the following claims, belong to the scope of the present invention .

Claims (18)

Aggregate (A); And
(B) containing cement, blast furnace slag, silica fume, silica powder, water and a water reducing agent,
The cement and blast furnace slag are mixed in proportions of 72 to 88 wt.% And 12 to 28 wt.% Respectively,
Wherein the binder is a mixture of 10 to 40 parts by weight of silica fume, 10 to 40 parts by weight of silica powder, 10 to 30 parts by weight of water, a mixture of carbon black and carbon fiber or carbon nanowires, based on 100 parts by weight of the mixture of cement and blast furnace slag 1 to 6 parts by weight of a carbon-based conductive filler, a styrene-butylene-styrene (SBS) block copolymer, a styrene-isoprene-styrene (SIS) block copolymer, a styrene- 5 to 20 parts by weight of any one of the elastomers selected from the group consisting of polyvinyl alcohol, polyvinyl pyrrolidone, carboxymethyl cellulose and polyethylene oxide, 5 to 10 parts by weight of a surfactant selected from the group consisting of water reducers 1 to 10 By weight,
Wherein a mixing weight ratio of the aggregate (A) and the binder (B) is 1.5: 1 to 3.0: 1.
delete delete The method according to claim 1,
Wherein the aggregate (A) comprises a fine aggregate having a particle size of 2.5 to 6.0 mm.
The method according to claim 1,
Wherein the silica fume has an average particle size of 0.01 to 1.0 占 퐉.
The method according to claim 1,
Wherein the silica powder has an average particle size of 1.2 to 2.5 占 퐉.
The method according to claim 1,
Wherein the water reducing agent is at least one selected from the group consisting of a polycarboxylic acid compound, a naphthalene compound and a lignin compound.
delete delete aggregate; And
A binder containing cement, blast furnace slag, silica fume, silica powder, water, a water reducing agent and a carbon-based conductive filler,
The cement and blast furnace slag are mixed in proportions of 72 to 88 wt.% And 12 to 28 wt.% Respectively,
Wherein the binder is a mixture of 10 to 40 parts by weight of silica fume, 10 to 40 parts by weight of silica powder, 10 to 30 parts by weight of water, a mixture of carbon black and carbon fiber or carbon nanowires, based on 100 parts by weight of the mixture of cement and blast furnace slag 1 to 6 parts by weight of a carbon-based conductive filler, a styrene-butylene-styrene (SBS) block copolymer, a styrene-isoprene-styrene (SIS) block copolymer, a styrene- 5 to 20 parts by weight of any one of the elastomers selected from the group consisting of polyvinyl alcohol, polyvinyl pyrrolidone, carboxymethyl cellulose and polyethylene oxide, 5 to 10 parts by weight of a surfactant selected from the group consisting of water reducers 1 to 10 By weight,
Wherein the weight ratio of the aggregate and the binder is in the range of 1.5: 1 to 3.0: 1.
11. The method of claim 10,
Wherein the smart permeable concrete product has a Fractional Change in Resistivity (FCR) measured according to ASTM-G57 satisfying the following formula (1).
[Formula 1]

(In the above equation 1, ρ ₀ is an initial electrical resistivity value not under load, and ρ _x is an electrical resistivity value with respect to a maximum tensile load measured when a load is applied.)
11. The method of claim 10,
The product is a smart pitching concrete product having a sensing purpose for sensing external force.
11. The method of claim 10,
The product is a smart pitching concrete product having self heating application.
a) 10 to 40 parts by weight of silica fume, 10 to 40 parts by weight of silica powder, 10 to 30 parts by weight of water, 1 to 6 parts by weight of a carbon-based conductive filler which is a mixture of carbon black and a carbon fiber or carbon nanowire, a styrene-butylene-styrene (SBS) block copolymer, a styrene-isoprene-styrene (SIS) 5 to 20 parts by weight of any one of ethylene-butylene-styrene (SEBS) based block copolymers, and any one selected from polyvinyl alcohol, polyvinylpyrrolidone, carboxymethylcellulose, and polyethylene oxide 5 to 10 parts by weight of a surfactant and 1 to 10 parts by weight of a water reducing agent; and
b) mixing the prepared binder with an aggregate containing fine aggregate,
Wherein the aggregates are mixed at a weight ratio of 1.5 to 3.0 relative to the binder.
delete 15. The method of claim 14,
Wherein the step a) comprises mixing the carbon-based conductive filler with water, dispersing the carbon-based conductive filler through a high-speed agitating means, and then mixing the carbon-based conductive filler with other components in the binder.
delete delete