KR20230077293A - Composite concrete structures that can capture carbon dioxide - Google Patents

Abstract

Disclosed is a composite concrete structure for capturing carbon dioxide. The composite concrete structure for capturing carbon dioxide according to the present invention comprises: core concrete prepared by using a carbonation curing method that captures carbon dioxide to form the center; coated concrete formed to a predetermined thickness around the core concrete by general curing methods; a reinforcement portion formed by arranging reinforcing bars around the coated concrete; and an external concrete formed to a predetermined thickness around the coated concrete by a general curing method such that the reinforcement portion is buried inside to form the outer appearance. According to the present invention, since contact between the core concrete and the reinforcing bars can be completely blocked, rapid corrosion of reinforcing bars, which is a problem with carbonation curing methods can be fundamentally prevented. Weakening of the durability of concrete caused by freezing and thawing due to water infiltration, acidification due to salt, and neutralization by water and carbon dioxide gas can be reduced. Capturing, utilizing, and storing carbon dioxide, which helps alleviate global warming is also possible at construction sites. In addition, It can be widely used without any special restrictions in conventional precast or construction sites. Accordingly, the composite concrete structure can be widely used without any special restrictions in conventional precast or construction sites.

Description

Carbon dioxide capture type composite concrete structure {COMPOSITE CONCRETE STRUCTURES THAT CAN CAPTURE CARBON DIOXIDE}

The present invention relates to a carbon dioxide capture type composite concrete structure, and more particularly, to a composite concrete structure with improved stiffness and durability by structurally utilizing concrete produced by a carbonation curing method for capturing, utilizing or storing existing carbon dioxide. It is about.

Greenhouse gases such as carbon dioxide and industrial by-products, such as carbon dioxide, are gradually accumulated worldwide due to the continuous production of steel and cement and the continuous operation of fossil power generation, which has a great impact on global warming.

Most of these industrial by-products are disposed of in landfills, but as they face problems such as the enormous cost of landfill disposal and limitations on landfill sites, industrial by-products are recycled or recycled in an eco-friendly way, or generated carbon dioxide (CO ₂ ) is captured. However, carbon capture & storage (CCS) is emerging as a new solution.

In particular, among the CCS technologies related to carbon dioxide, which is recognized as the main culprit of global warming, technologies such as Korean Patent Registration No. 10-1863671 (registration date: May 28, 2018) related to the present invention are accelerated mineral carbonation As a carbon capture technology using a reaction process, in addition to the existing hydration reaction, it is a technology that promotes the reaction of cement components and carbon dioxide under a specific pressure to cure concrete.

As an example, concrete produced through carbonation curing in which carbon dioxide is injected for 2 hours under conditions of about 23 ° C, pressure of 0.1 bar, and humidity of about 50% to 70% forms a dense structure by a chemical reaction that reduces voids, It has been reported that durability is improved by increasing resistance to surface permeability, freeze-thaw, and sulfate penetration, while mechanical stiffness close to that of concrete cured in wet conditions for 28 days has been realized.

Due to the technical advantages of capturing (reducing) carbon dioxide in concrete along with the improvement of physical properties of such concrete structures, various technologies for performing or using carbonation curing by injecting carbon dioxide have recently been proposed.

However, since the pH of concrete produced by the carbonation curing method is rapidly lower (approximately pH: 9 to 10) than that of concrete cured by the general curing method (approximately pH: 12), when reinforcing bars are used as reinforcing materials for carbonation curing concrete, rapid corrosion of the reinforcing bars occurs. There is a problem that causes this.

Therefore, the conventional technology of reinforcing carbonation curing concrete using reinforcing bars has not yet been widely applied to precast or pouring sites due to the above problems, and carbonation is performed on plain concrete products such as bricks, blocks, and facades. Curing methods are being used on a limited basis.

Therefore, it will be necessary to research and develop various methods that can specifically solve the problems or limitations that occur when carbonation curing is applied to reinforced concrete structures.

Republic of Korea Patent Registration No. 10-1863671 (registration date: May 28, 2018)

An object of the present invention is to contribute to the resolution of global warming by collecting, utilizing or storing carbon dioxide in concrete, and to configure it to be able to reinforce concrete using a carbonation curing method that improves the physical properties of concrete, so that it can be used for precast or construction sites, etc. It is to provide a carbon dioxide capture type composite concrete structure that can be widely applied.

The above object is produced by a carbonation curing method for capturing carbon dioxide and constituting the core concrete; Coating concrete formed to a predetermined thickness around the core concrete by a general curing method; Reinforcing part formed by reinforcing bars around the circumference of the coated concrete; And it is achieved by a carbon dioxide capture type composite concrete structure including an outer concrete formed to a predetermined thickness around the coated concrete by a general curing method so that the reinforcing part is buried inside to form an exterior.

A surface of the core concrete may be provided with a plurality of first grooves spaced apart along the circumferential direction of the core concrete and formed concavely in the longitudinal direction of the core concrete to increase a contact area with the coating concrete.

A plurality of second grooves spaced apart from each other along the longitudinal direction of the core concrete and concavely formed in the circumferential direction of the core concrete to cross the first groove may be further provided on the surface of the core concrete.

The carbon dioxide capturing composite concrete structure may further include protective concrete formed to a predetermined thickness around the outer concrete by a carbonation curing method for capturing carbon dioxide to prevent penetration by external foreign substances.

A phase change material may be filled in some of the first groove and the second groove to increase the temperature resistance of the carbon dioxide capturing composite concrete structure.

According to the present invention, the coating concrete of the general curing method is formed to a predetermined thickness around the core concrete produced by the carbonation curing method for capturing carbon dioxide and constituting the center, and the reinforcement part reinforced with reinforcing bars is placed around it, so that the core Contact between concrete and reinforcing bars can be completely blocked, so rapid corrosion of reinforcing bars, which is a problem in the carbonation curing method, can be fundamentally prevented, freezing and thawing due to water penetration, acidification due to salt, neutralization by water and carbon dioxide gas, etc. It can reduce the durability of concrete caused by this, and there is an effect that the capture, utilization or storage of carbon dioxide that helps to solve global warming can be done in the construction field.

In addition, as the outer concrete by the general curing method is poured to a predetermined thickness around the coated concrete so that the above-mentioned reinforcing part is buried inside to form a general structure of composite concrete, the present invention can be used in precast or construction sites as in the prior art. There is an effect that can be widely used without special restrictions.

1 is a perspective view of a carbon dioxide capture type composite concrete structure according to an embodiment of the present invention.
Figure 2 is a process chart showing the manufacturing process of the core concrete of Figure 1 step by step.
Figure 3 is a process chart showing the manufacturing process of the coated concrete of Figure 1 step by step.
4 is a process chart showing the manufacturing process of the reinforcement part and the outer concrete of FIG. 1 step by step.
5 is a perspective view of a carbon dioxide capture type composite concrete structure according to a modified example of the present invention.
6 is a process chart showing the manufacturing process of the protective concrete of FIG. 5 step by step.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, in describing the present invention, descriptions of already known functions or configurations will be omitted to clarify the gist of the present invention.

1 is a perspective view of a carbon dioxide capturing composite concrete structure according to an embodiment of the present invention, FIG. 2 is a process diagram showing the manufacturing process of the core concrete of FIG. 1 step by step, and FIG. 3 is the manufacturing process of the coated concrete of FIG. It is a process chart showing step by step, Figure 4 is a process chart showing the manufacturing process of the reinforcement part and the outer concrete step by step in Figure 1, Figure 5 is a perspective view of a carbon dioxide capture type composite concrete structure according to a modified example of the present invention, Figure 6 is It is a process chart showing the manufacturing process of the protective concrete of FIG. 5 step by step.

Top (top), bottom (bottom), left and right (side or side), front (front, front), back (back, back), etc., which refer to directions in the description and claims of the invention, etc., are not intended to limit the use of rights. For convenience of description, the relative position between the drawings and configurations is determined as a standard, and the three axes may be rotated and changed to correspond to each other, and this is followed unless otherwise specifically defined.

The carbon dioxide capturing composite concrete structure 100 according to the present invention, while taking advantages such as strengthening concrete durability and rigidity, fundamentally prevents rapid corrosion of reinforcing bars, which is a problem in carbonation curing, so that reinforcement of concrete using reinforcing bars, etc. It is an invention devised to achieve the same.

In order to specifically implement the above-described actions or functions, the carbon dioxide capture type composite concrete structure 100 according to the present invention, as shown in FIG. 130 and outer concrete 140, etc., and as shown in FIG. 5, it can be composed of a modified example further including protective concrete 150 and phase change material (PM) in the configuration of the embodiment. there is.

Here, the composite concrete structure 100 may be any one of the structural elements of a building or civil engineering structure 100, such as a slab constituting a floor or a roof, a beam for supporting a slab, and a column or wall supporting between upper and lower slabs. there is.

However, in the present invention, for convenience of description, each of the above-described components is described based on a rectangular parallelepiped beam as shown in FIG. It can be dedicated and understood.

The core concrete 110 is a component provided to enhance the durability and mechanical rigidity of the composite concrete structure 100 based on the center according to the present invention, and improves durability and mechanical rigidity by capturing carbon dioxide rather than a general curing method. It is characterized by a technical feature that is produced by the carbonation curing method.

In the specific manufacturing process (S100) of the core concrete 110, first, a mixture obtained by mixing aggregates such as sand and gravel, cement paste, various admixtures, and carbonation-accelerating additives in a certain ratio is prepared in FIG. 2 (a) A process of pouring into the formwork 10 shown in and placing in a rectangular parallelepiped shape is performed.

Next, as shown in FIG. 2 (b), after placing the core concrete 110 in a state in which the shape is maintained in the carbonation curing chamber 30 of a closed structure equipped with a spacer 12, etc., the core concrete A process of curing (110) with a carbonation curing method for a predetermined time is performed.

At this time, the carbonation curing to hardening process performed on the core concrete 110 in the carbonation curing chamber 30 maintains the concentration of carbon dioxide in the carbonation curing chamber 30 constant at 5% to 10%, and 7 to 14 can be done over the course of a day.

The carbonation cured core concrete 110 through the above series of processes can be chemically stabilized by densifying the surface layer, that is, forming a high-density microstructure through a chemical reaction that fills the voids inside the compound.

As a result, the weakening of concrete caused by freezing and thawing due to water infiltration, acidification due to salt, and neutralization due to water and carbon dioxide is effectively reduced, thereby increasing durability as well as carbonic acid, a reaction product of carbon dioxide capture. Formation of calcium or the like can improve mechanical rigidity.

On the other hand, on the surface of the core concrete 110, as shown in FIGS. 1 and 5, a plurality of first grooves 112 and second grooves 114 may be formed, which is a coating concrete 120 to be described later. This is to increase the contact area with the coated concrete 120 and improve the bonding force.

Here, the first groove 112 is a component spaced apart along the circumferential direction of the core concrete 110 and formed concavely in the longitudinal direction of the core concrete 110, as shown in FIG.

As shown in (c) of FIG. 2, the first groove 112 may be formed through the cutting process of the cutting cutter 20 on the core concrete 110 where carbonation curing is completed.

In addition, as shown in FIG. 5, the second grooves 114 are spaced apart along the longitudinal direction of the core concrete 110 and are concave in the circumferential direction of the core concrete 110 to intersect with the above-described first groove 112. As a component formed to be, although not specifically shown, it may be formed through the cutting process of the cutting cutter 20, like the first groove 112.

At this time, the first groove 112, as shown, has a width and a depth of 10 mm to 15 mm, and is shown as being formed in two on the surface, but the first groove 112 and the second groove 114 Of course, the number of grooves, the width and depth of the grooves, and the interval between formations can be appropriately increased or decreased in consideration of the combination of the core concrete 110, the length and surface area of the core concrete 110, and the like.

The coating concrete 120 is a component provided to allow the above-described core concrete 110, which causes rapid corrosion of reinforcing bars due to low pH, and reinforcement by reinforcing bars, etc. to be applied together. It is technically characterized by being formed to a predetermined thickness around the core concrete 110 by a different general curing method.

In the specific manufacturing process (S200) of the coated concrete 120, first, as shown in (a) of FIG. , Aggregates such as sand and gravel, cement paste, various admixtures, etc. are mixed at a certain ratio into the formwork 10 to form a coating layer with a thickness of about 10 mm to 20 mm on the outer surface of the core concrete 110. process will be carried out.

At this time, the mixture forming the coating concrete 120 is viscous self-filling that can be uniformly filled in the above-described first groove 112 and second groove 114 without gaps only with its own weight without separate compaction work during pouring. It can be castle concrete.

Next, the coated concrete 120, which is cast as above and maintained in shape, is placed in the water-filled curing tank 40 as shown in FIG. 3 (b), followed by a general curing method for about 7 days. (Water curing) to perform a hardening process.

At this time, the reason why water curing, which is a type of wet curing among general curing methods, is selected is to promote the formation of additional hydration products through the continuous hydration process of concrete itself.

The high pH coating concrete 120 formed by the above general curing method has a predetermined thickness on the core concrete 110 so that the low pH core concrete 110 as described above and the reinforcement part 130 to be described later do not come into contact with each other. As the coating layer is formed, corrosion of reinforcing bars, etc. constituting the reinforcing portion 130 can be fundamentally prevented, and reinforcement by reinforcing bars and application of the core concrete 110 can be performed together.

The reinforcing part 130 is a component formed by reinforcement (S300) with reinforcing bars around the high pH coated concrete 120 as described above in order to compensate for the insufficient tensile strength, which is a disadvantage of concrete, and the main reinforcing bars 132 ) and costal muscle 134.

Here, the main reinforcing bars 132, as shown in FIGS. 1 and 4 (a), in order to resist the tensile and compressive forces applied to the beam, which is a rectangular parallelepiped structural element, are arranged in plurality above and below the beam. It is a rebar that is installed.

In addition, the costal muscles 134 (or stirrups) are spaced apart along the longitudinal direction of the beam to resist the shear force applied to the beam while fixing the above-described main reinforcing bars 132, and bent L-shaped, U-shaped, or rectangular main reinforcing bars It is a reinforcing bar installed to surround (132).

As described above, the arrangement interval, number, thickness, etc. of the main reinforcing bars 132 and ribs 134 that are placed in contact with the circumference of the coated concrete 120 depend on the size or shape of the composite concrete structure 100 according to the present invention, the combination of concrete, etc. Of course, it can be appropriately increased or decreased or changed in consideration of the above.

The outer concrete 140 is a component that forms the appearance of the composite concrete structure 100 according to the present invention, and is coated around the coated concrete 120 by a general curing method so that the above-described reinforcing part 130 is buried inside. It may be formed to a predetermined thickness.

In the specific manufacturing process (S400) of the outer concrete 140, first, as shown in (b) of FIG. A process of seating the formed mold 10 is performed.

In addition, a process of pouring a mixture of aggregates such as sand and gravel, cement paste, various admixtures, etc. at a certain ratio into the formwork 10 to form the outer concrete 140 on the outer surface of the coating concrete 120 will perform

The mixture at this time may be the same composition as the above-described mixture of the coated concrete 120, and may be a mixture of a composition changed according to the installation environment of the composite concrete structure 100 according to the present invention, and without separate compaction work during casting. It may be viscous self-filling concrete that can be uniformly filled between the reinforcing parts 130 described above with only its own weight.

On the other hand, before pouring the mixture, a thin epoxy layer may be applied to the surface of the coated concrete 120, which is a barrier between the outer concrete 140 to be poured and the coated concrete 120 reinforced by the reinforcing part 130. This is to ensure that the bonding force is firmly and densely formed.

Next, after being poured as above, the outer concrete 140, which has been cured for about 24 hours and maintained in shape, is seated in the water-filled curing tank 40 as shown in FIG. 4 (c), A curing process is performed according to a general curing method (underwater curing) for about 24 to 28 days.

At this time, the reason why water curing, which is a type of wet curing among general curing methods, is selected is to promote the formation of additional hydration products through the continuous hydration process of concrete itself.

Due to the formation of the high pH outer concrete 140 by the above general curing method, the composite concrete according to the present invention can be structurally strengthened through the reinforcement part 130 such as a reinforcing bar in the same way as in the prior art, and functions as a core material. Through the low pH core concrete 110, it is possible to promote superior durability and mechanical rigidity from the inside compared to the prior art.

As shown in FIG. 5, the carbon dioxide capturing composite concrete structure 100 according to a modified example of the present invention includes a protective concrete 150 and a phase change material (PM) in addition to the configuration in the above-described embodiment. may be further included.

Here, the protective concrete 150 is a component that is disposed on the outermost periphery of the composite concrete according to the present invention to prevent the penetration of external foreign substances, and a predetermined amount is placed around the outer concrete 140 described above by a carbonation curing method for collecting carbon dioxide. It is formed with a thickness.

In the specific manufacturing process (S500) of the protective concrete 150, first, as shown in FIG. 110 is seated on the formwork 10 equipped with the spacer 12 and the like is performed.

In addition, a mixture obtained by mixing aggregates such as sand and gravel, cement paste, various admixtures and carbonation-accelerating additives at a certain ratio is injected into the formwork 10, and the protective concrete 150 is formed on the outer surface of the outer concrete 140. The pouring process is performed to form.

The mixture at this time may be the same composition as the above-mentioned mixture of the core concrete 110, may be a mixture of a composition changed according to the installation environment of the composite concrete structure 100 according to the present invention, and can be filled uniformly without gaps. It can be a viscous self-filling concrete.

On the other hand, before pouring the above-described mixture, a thin epoxy layer may be applied to the surface of the coated concrete 120, which forms a strong and dense bonding force between the poured protective concrete 150 and the outer concrete 140. is to make it

Next, as shown in FIG. 6 (b), the protective concrete 150 is hardened to the extent that the shape is maintained in the carbonation curing chamber 30 of a closed structure equipped with a spacer 12, etc. After that, a process of hardening the protective concrete 150 by a carbonation curing method for a predetermined time is performed.

At this time, the carbonation curing to hardening process performed on the protective concrete 150 in the carbonation curing chamber 30 maintains the concentration of carbon dioxide in the carbonation curing chamber 30 constant at 5% to 10%, and 20 to 25 can be done over the course of a day.

Since the low pH protective concrete 150 is formed on the outermost surface by the above carbonation curing method, the composite concrete according to the present invention can be structurally strengthened through the reinforcement part 130 such as a reinforcing bar as in the prior art, as well as And, through the low pH core concrete 110 serving as the core material and the outermost low pH protective concrete 150, it is possible to exhibit excellent durability and mechanical rigidity compared to the prior art on the inside and outside, respectively.

Meanwhile, in some of the first groove 112 and the second groove 114, a phase change material (PM) may be filled in order to increase the temperature resistance of the carbon dioxide capturing composite concrete structure 100.

Here, the phase change material (PM) is a temperature control material that changes state from solid to liquid or from liquid to solid based on a specific temperature range and stores heat (endothermic) or emits heat (heat dissipation), respectively. Alternatively, it may be manufactured to be phase-changed in an intended arbitrary temperature range using various vegetable substances that can be obtained from nature.

Among the phase change materials (PM) prepared as described above, the phase change material filled in the first groove 112 or the second groove 114 according to the modified example of the present invention is installed in the composite concrete structure 100 according to the present invention. Depending on the environment (cold zone, temperate zone, tropical region, etc.), the phase change temperature range may be set to -6 ° C to 6 ° C, 15 ° C to 20 ° C, or 30 ° C to 35 ° C.

When the phase change material (PM) in this temperature range is partially filled in at least one of the first groove 112 and the second groove 114 and the coated concrete 120 is formed, the area around the composite concrete structure 100 Even if the temperature changes, as the temperature change applied to the structure 100 is buffered at a constant level, fatigue applied to the structure 100 from the external environment can be reduced.

In the foregoing, although specific embodiments of the present invention have been described and shown, the present invention is not limited to the described embodiments, and it is common knowledge in the art that various modifications and variations can be made without departing from the spirit and scope of the present invention. It is self-evident to those who have Therefore, such modifications or variations should not be individually understood from the technical spirit or viewpoint of the present invention, and modified embodiments should fall within the scope of the claims of the present invention.

10: formwork
12: Spacer
20: cutting cutter
30: carbonation curing chamber
40: curing tank
100: carbon dioxide reduction composite concrete structure
110: core concrete
112: first groove
114: second groove
120: coated concrete
130: reinforcement part
132: main bar
134: intercostal muscles
140: outer concrete
150: protective concrete
PM: phase change material

Claims (5)

Core concrete constituting the center produced by the carbonation curing method for capturing carbon dioxide;
Coating concrete formed to a predetermined thickness around the core concrete by a general curing method;
Reinforcing part formed by reinforcing bars around the circumference of the coated concrete; and
A carbon dioxide capture type composite concrete structure comprising an outer concrete formed to a predetermined thickness around the coated concrete by a general curing method so that the reinforcing part is buried inside to form an appearance. According to claim 1,
On the surface of the core concrete,
Carbon dioxide trapping composite concrete structure, characterized in that provided with a plurality of first grooves spaced apart along the circumferential direction of the core concrete and formed concavely in the longitudinal direction of the core concrete to increase the contact area with the coating concrete. According to claim 2,
On the surface of the core concrete,
A plurality of second grooves spaced apart along the longitudinal direction of the core concrete and formed concavely in the circumferential direction of the core concrete to intersect with the first groove carbon dioxide capturing composite concrete structure, characterized in that further provided. According to claim 2,
The carbon dioxide capturing composite concrete structure,
A carbon dioxide capturing composite concrete structure, characterized in that it further comprises protective concrete formed to a predetermined thickness around the outer concrete by a carbonation curing method for capturing carbon dioxide to prevent penetration by external foreign substances. According to claim 3,
In some of the first groove and the second groove,
In order to increase the temperature resistance of the carbon dioxide capturing composite concrete structure, the carbon dioxide capturing composite concrete structure, characterized in that the phase change material is filled.

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