JP5957283B2 - Manufacturing method of concrete products - Google Patents

Description

  The present invention relates to a method for manufacturing a concrete product, and more particularly to a method for manufacturing an environmentally friendly concrete product in which carbon dioxide is absorbed.

  In recent years, so-called environmentally friendly concrete products in which carbon dioxide is absorbed into concrete have been studied as a measure for reducing carbon dioxide (carbon dioxide) emissions. As a technique in such a field, for example, as described in Patent Document 1 below, a hardened cement body is accommodated in a shielded space shielded from an external atmospheric environment, and carbon dioxide gas is supplied into the shielded space. A technique for absorbing carbon dioxide in a hardened cement body is known. Performing concrete curing while absorbing carbon dioxide in this way is called carbonation curing. In the method described in Patent Document 1, after placing a mortar kneaded material on a mold, curing, demolding, and taking about 5 days while exposing the surface of the obtained cement hardened body to carbon dioxide gas. Carbonated and cured.

  Further, as described in Patent Document 2 below, an air passage is formed inside the concrete molded body, and carbon dioxide gas is also fed into the concrete molded body through this air passage, so that the carbon dioxide gas absorption capacity in the concrete molded body A technology that increases the speed is known.

JP 2009-149456 A JP 2008-8025 A

  However, in the technique described in Patent Document 1, since the surface of the hardened cement body is exposed to carbon dioxide gas, carbon dioxide gas can be absorbed at a certain depth from the surface. For example, the thickness of the hardened body is large. Then, it was difficult to absorb the carbon dioxide gas to the deep part inside. Further, in the technique described in Patent Document 2, although a ventilation path is formed, carbon dioxide gas can be absorbed only in a limited area around the ventilation path. It was insufficient.

  An object of this invention is to provide the manufacturing method of the concrete product which can increase the absorption amount of a carbon dioxide gas.

A method for producing a concrete product that solves the above-mentioned problem is to open at least one material of porous concrete, recycled aggregate, concrete lump, and solidified material mainly composed of industrial byproducts including blast furnace slag or fly ash. Filling a mold having a carbon dioxide, supplying a carbon dioxide-containing gas into the mold through a supply pipe inserted from the opening, and carbonating at least one kind of material, and filling at least one kind of material. Filling a solidified material containing cement into the voids in the formed region, and solidifying the solidified material.

  According to this concrete manufacturing method, the mold is filled with at least one material of porous concrete, recycled aggregate, concrete block, and solidified material containing industrial by-products as main components, and the filled At least one material is carbonated. Porous concrete is porous, and solidified material mainly composed of recycled aggregate, concrete block, or industrial by-product forms voids, so that carbon dioxide-containing gas tends to spread throughout the carbonization. That is, the thickness of each member to be carbonated is reduced. Therefore, carbon dioxide gas can be absorbed even inside the material such as porous concrete and recycled aggregate, and the amount of carbon dioxide gas absorbed can be increased. Here, carbonation is performed by supplying carbon dioxide-containing gas into the mold through a supply pipe inserted from the opening of the mold. Therefore, the mold itself becomes a shield that shields from the external atmospheric environment during carbonation, and there is no need to provide a curing tank as in the conventional carbonation curing. Since the voids in the region filled with the at least one kind of material are filled with the solidifying material and solidified, for example, the voids remain, so that the overall specific gravity is reduced and used in the water area. It is possible to prevent buoyancy from occurring and water from entering the inside, and the quality equivalent to that of a normal dense concrete product is realized.

  Further, in the above concrete product manufacturing method, the mold is an assembly of a plurality of parts, and before the carbonation step, a sealing member for enhancing the airtightness in the mold is provided between the parts. A step of disposing. In particular, when the concrete product is large or has a complicated shape, it is common to use a mold that can be divided into a plurality of parts. In this manufacturing method, the mold itself is a shield against the atmospheric environment, but sealing members are disposed between a plurality of parts to improve the airtightness in the mold, so that porous concrete, recycled aggregate, etc. The absorption efficiency of carbon dioxide with respect to the material can be ensured. Moreover, the pressure in a formwork can also be raised and the period required for carbonation can be shortened.

  In the concrete product manufacturing method, in the step of filling and solidifying the solidifying material, the solidifying material is injected using a supply pipe. In this case, by using the supply pipe used for supplying the carbon dioxide-containing gas also for the injection of the solidified material, the solidified material can be reliably and easily filled into the region filled with at least one kind of material. it can.

  The method for producing a concrete product may further include a step of inserting a discharge pipe and a supply pipe for discharging exhaust gas from the formwork through the opening before the carbonation step. The length of the tube in the mold is made longer than the length of the discharge tube in the mold. In this case, since the supply pipe is inserted deeply into the mold, it is possible to reliably distribute the carbon dioxide-containing gas throughout the mold.

  Further, in the above concrete product manufacturing method, the mold has a plurality of openings, and in the carbonation step, carbon dioxide is contained in a plurality of locations in the mold through supply pipes inserted into the plurality of openings. Supply gas. In this case, since the carbon dioxide-containing gas is supplied to a plurality of locations in the mold, the carbon dioxide-containing gas can be reliably distributed throughout the mold.

  In the method for producing a concrete product, in the step of filling at least one kind of material, heavy aggregate is used as an aggregate of porous concrete or as a recycled aggregate. In this case, the specific gravity as a concrete product increases, and stability against external force can be enhanced. For example, when a concrete product is applied to a wave-dissipating block, a high wave-dissipating effect can be obtained.

  According to the present invention, the amount of carbon dioxide absorbed can be increased.

(A)-(c) is a perspective view which shows the manufacturing procedure which concerns on 1st Embodiment. (A) And (b) is a perspective view which shows the manufacturing procedure following FIG. It is a perspective view which shows the end cover for closing opening of a formwork. (A)-(c) is a perspective view which shows the manufacture procedure which concerns on 2nd Embodiment. (A)-(c) is a perspective view which shows the manufacturing procedure following FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and redundant descriptions are omitted.

  As shown in FIGS. 1 and 2, the wave-dissipating block (concrete product) 12 is an environmentally friendly concrete secondary product that absorbs carbon dioxide gas. In this embodiment, the wave-dissipating block 12 and the manufacturing method thereof will be described as an example. However, the wave-dissipating block 12 is not limited to the wave-dissipating block. For example, various types such as pedestrian boundary blocks, land boundary blocks, fence foundation blocks, gutter blocks, fishing reef blocks, etc. Concrete blocks can also be manufactured. In the present embodiment, a four-leg type wave-dissipating block 12 will be described as an example, but the number and shape of the legs are not limited thereto. Even in the case of a concrete block other than the wave-dissipating block, it can have any shape such as a quadrangular pyramid shape, a rectangular parallelepiped shape, a columnar shape, a truncated cone shape, and the like. Any shape can be used as long as it is a concrete block manufactured by using a mold having an opening in a part and the other part being closed.

  The wave-dissipating block 12 is mainly made of porous concrete 3 that has absorbed carbon dioxide gas. Carbon dioxide gas is absorbed in this porous concrete 3 by the manufacturing method mentioned later. Cement milk 11 is filled in the voids of the porous concrete 3. The wave-dissipating block 12 has a smooth surface state and has no voids inside. Therefore, the appearance of the wave-dissipating block 12 is not changed from that of a normal solid wave-dissipating block.

  Then, the manufacturing method of the wave-dissipating block 12 is demonstrated. In the manufacturing method of the present embodiment, the size of the wave-dissipating block 12 is not limited, but the following manufacturing method is particularly suitable for manufacturing the medium-sized (several tons) to large-sized (several tens of tons) wave-dissipating blocks 12. Yes.

  First, as shown in FIG. 1A, a mold 1 is prepared. This formwork 1 is an assembly of a plurality of iron parts 2. The plurality of parts 2 include, for example, a mold called a shell that forms the side surface of the wave-dissipating block 12 and a mold called an end plate that forms the distal end surface of the leg of the wave-dissipating block 12. A circular opening 1a is formed at the upper end portion (the portion corresponding to the end portion of one of the four legs) of the mold 1 in a state where a plurality of parts 2 are assembled. Between each part 2, the sealing member 9 for improving the airtightness in the mold 1 is disposed. More specifically, a seal member 9 made of hard rubber, for example, is interposed over substantially the entire seam between the parts 2. By this sealing member 9, the inside of the mold 1 can be kept in a carbon dioxide gas atmosphere during carbonation, and the porous concrete 3 filled in the mold 1 can be suitably carbonated. The mold 1 is placed on a steel mount 4.

  In FIGS. 1B, 1C, and 2A, the part 2 that should be illustrated on the front side of the paper surface is excluded for easy explanation.

  Next, as shown in FIG. 1B, a supply pipe 6 for supplying a carbon dioxide-containing gas into the mold 1 and a discharge pipe 7 for discharging exhaust gas from the mold 1 are provided. Attach to formwork 1. More specifically, the supply pipe 6 and the discharge pipe 7 made of a steel pipe are inserted from the opening 1a and fixed to the mold 1 at predetermined positions. Here, the supply pipe 6 is arranged so that the end of the supply pipe 6 inserted into the mold 1, that is, the outlet end of carbon dioxide reaches the back side of the center position (center of gravity) of the mold 1. On the other hand, the discharge pipe 7 is disposed so that the end portion (exhaust gas inlet end portion) of the discharge pipe 7 inserted into the mold 1 is located on the near side of the center position (center of gravity) of the mold 1. That is, the length of the supply pipe 6 in the mold 1 is made longer than the length of the discharge pipe 7 in the mold 1. In this manner, by separating the end of the supply pipe 6 and the end of the discharge pipe 7 by a certain distance, the carbon dioxide-containing gas can be distributed throughout the porous concrete 3 in the mold 1 during carbonation. it can.

  Here, a plurality of holes may or may not be provided in a portion of the supply pipe 6 in the mold 1. When a plurality of holes are provided, carbon dioxide diffuses horizontally in the mold 1 through the holes during carbonation. When no hole is provided, carbon dioxide gas is released from the outlet end and diffuses.

Next, the porous concrete 3 is filled in the mold 1 until the position of the opening 1a is reached. The porous concrete 3 preferably contains a dicalcium silicate γ phase (γ-C ₂ S) excellent in CO ₂ absorption performance, but may not contain a dicalcium silicate γ phase. The maximum particle size and particle size distribution of the porous concrete 3 are appropriately set in consideration of spreading the cement milk 11 (see FIG. 2 (a)) injected last. The porosity of the porous concrete 3 is preferably 10 to 30% or more.

  More specifically, ordinary Portland cement can be used as the cement of the porous concrete 3, and blast furnace cement B type can also be used. Tables 1 and 2 show examples of materials used for porous concrete and examples of blending, respectively.

  Gaps are formed in the entire area of the mold 1 filled with the porous concrete 3. Note that it is not necessary to fill the porous concrete 3 until the position of the opening 1a is reached, and the porous concrete 3 may not reach the opening 1a. The filling accuracy of the porous concrete 3 may be low. For example, even if a region where the porous concrete 3 is not filled is formed in the lower part of the mold 1, there is no particular problem because the cement milk 11 is filled later.

  Next, an end cover (lid) 10 shown in FIG. 3 is fitted into the opening 1 a and fixed to the mold 1. The end cover 10 is a disk-shaped member, and the supply pipe 6 and the discharge pipe 7 pass through, and the outer portion of the supply pipe 6 and the discharge pipe 7 in the opening 1a is sealed. A seal member may be provided between the end cover 10 and the supply pipe 6 and the discharge pipe 7. Further, the present invention is not limited to the case where the supply pipe 6 and the discharge pipe 7 are passed through the end cover 10, and two short pipes constituting a part of the supply pipe 6 and the discharge pipe 7 are provided integrally with the end cover 10 in advance. Alternatively, the supply pipe 6 and the discharge pipe 7 may be connected to both ends (both ends inside and outside the mold 1) of these short tubes.

  After the initial curing of the porous concrete 3, as shown in FIG. 1C, the supply pipe 6 and the discharge pipe 7 are connected to the curing system 8, and the carbon dioxide-containing gas is sealed in the mold 1. Carbonation curing is performed while keeping the inside of the mold 1 in a carbon dioxide gas atmosphere. The initial curing period until the carbonation curing is performed is, for example, about 1 to 4 days. Carbonation curing is performed at a carbon dioxide gas concentration of 5 to 100%, a temperature of 20 to 80 ° C., a humidity of 30 to 70% RH, for example, over about two weeks. Thereby, the carbonized body 13 (refer FIG. 2A) which absorbed the carbon dioxide gas inside is formed. In addition, the carbonation curing period can be shortened to about 3 days by making the inside of the mold 1 into a high-pressure atmosphere. The mold 1 and the curing system 8 may be adjacent to a carbon dioxide generating site such as a thermal power plant, and the exhaust gas containing carbon dioxide may be introduced into the mold 1. Thus, in this embodiment, the curing tank (shielding body which forms shielding space) conventionally required is made unnecessary.

  Next, as shown in FIG. 2 (a), the discharge side of the concrete pump A is connected to the supply pipe 6, and the cement milk 11 as a solidifying material in the voids in the carbonized body 13 using the supply pipe 6. Inject and solidify. In addition, you may use a mortar and a paste as a solidification material. The supply pipe 6 and the discharge pipe 7 may be pulled out after the cement milk 11 is filled, or may be left as it is to cut the protruding portion.

  Then, after curing for a certain period, demolding is performed, and the concrete block 12 shown in FIG. 2B is completed. By filling the solidified material in the voids in the carbonated body 13 and solidifying in this way, strength and weight as a concrete block can be secured, and after installation, water and soil can be prevented from entering the interior. it can. Moreover, the surface 12a of the wave-dissipating block 12 becomes smooth, and the appearance as a concrete product is maintained.

  According to the manufacturing method of the wave-dissipating block 12 described above, since the porous concrete 3 filled in the mold 1 is porous, the carbon dioxide-containing gas tends to spread throughout the carbonation. Therefore, carbon dioxide is absorbed to the inside of the porous concrete 3, and the amount of carbon dioxide absorbed can be increased. Here, since carbonation is performed by supplying carbon dioxide-containing gas into the mold 1 through the supply pipe 6 inserted from the opening 1a of the mold 1, the mold 1 itself becomes a shield, There is no need to provide a curing tank as in the case of carbonation curing. In the case of the large wave-dissipating block 12, there is no need to prepare a large curing tank for housing it, so that it is particularly effective. Since the cement milk 11 is filled in the voids in the carbonated body 13 made of the porous concrete 3 and solidified, for example, the voids remain, so that the overall specific gravity is reduced and used in water. It is possible to prevent buoyancy from occurring and water from entering the inside, and the quality equivalent to that of a normal dense concrete product is realized. Furthermore, according to the carbonized wave-dissipating block 12, the effect that the wave-dissipating effect is higher than that of a normal concrete block is also exhibited.

  When the concrete product is large or has a complicated shape, it is common to use a mold that can be divided into a plurality of parts. In the present embodiment, the mold 1 itself becomes a shield against the atmospheric environment, but the sealing member 9 is disposed between the plurality of parts 2 to improve the airtightness in the mold 1, thereby preventing the porous concrete 3. Carbon dioxide absorption efficiency is ensured. Moreover, the pressure in the mold 1 can be increased, and the period required for carbonation can be shortened.

  Further, by using the supply pipe 6 used for supplying the carbon dioxide-containing gas also for injecting the cement milk 11, the cement milk 11 can be reliably and easily filled into the carbonized body 13 made of the porous concrete 3. it can.

  Further, by making the length of the supply pipe 6 in the mold 1 longer than the length of the discharge pipe 7 in the mold 1, the supply pipe 6 is inserted deeply into the mold 1 and the carbon dioxide-containing gas is injected into the mold. The entire frame 1 can be reliably distributed. This is particularly effective in the case of the large wave-dissipating block 12.

  4 and 5 are perspective views showing a manufacturing procedure of the wave-dissipating block 12 according to the second embodiment. The manufacturing method of the present embodiment is different from the manufacturing method of the first embodiment in that instead of the mold 1, circular openings 1b and 1c are provided in portions corresponding to the end portions of the legs in addition to the openings 1a. A point using the mold 1A, a point using a supply pipe 6A having a plurality of supply pipes 6a, 6b, 6c corresponding to the openings 1a, 1b, 1c instead of the supply pipe 6, and the openings 1a, 1b, The point is that the carbon dioxide-containing gas is supplied through the supply pipes 6a, 6b, and 6c inserted into the respective 1c. In this case, the tips of the supply pipes 6 a, 6 b, 6 c have entered the vicinity of the center position (center of gravity) of the mold 1, and supply carbon dioxide-containing gas to four locations in the mold 1. The openings 1b and 1c are sealed by the end cover 10 as in the first embodiment. Further, when the cement milk 11 is injected, the lower supply pipes 6b and 6c are removed, and the openings 1b and 1c are closed by the end plate. 4 and 5, the opening on the back side of the drawing and the supply pipe are not shown.

  Also by such a manufacturing method, the same effect as 1st Embodiment can be acquired. Moreover, since the carbon dioxide-containing gas is supplied to a plurality of locations in the mold 1A, the carbon dioxide-containing gas can be reliably distributed throughout the mold 1A. This is particularly effective in the case of the large wave-dissipating block 12.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to the said embodiment. For example, instead of porous concrete 3, recycled aggregate may be filled into the mold 1. According to such a manufacturing method, since recycled aggregate is used, a concrete product that is effective for recycling and more environmentally friendly can be realized. Furthermore, it is not limited to recycled aggregates, and the mold 1 may be filled with a concrete lump obtained at the time of demolition of a concrete structure or a solidified material containing industrial by-products as main components. In this case, the demolished concrete block can be thrown in with a relatively large diameter of 40 mm or more. Examples of solidified products containing industrial by-products as main components include blast furnace slag and fly ash that have been consolidated to a relatively large diameter. Even in these cases, the filling accuracy of the solidified material containing the recycled aggregate, the concrete block, or the industrial by-product in the mold 1 as a main component may be low. Further, any two or more kinds of materials among porous concrete 3, recycled aggregate, concrete lump, and solidified material containing industrial by-products as main components may be filled in the mold 1 together. For example, recycled aggregate may be used as the aggregate of the porous concrete 3.

  Further, a heavy aggregate may be used as the aggregate of the porous concrete 3 or as a recycled aggregate. In this case, the specific gravity as a concrete product increases, and stability against external force can be enhanced. For example, when applied to a wave-dissipating block, a high wave-dissipating effect can be obtained.

  The formwork 1 may not be divided into a plurality of parts 2. Further, the seal member 9 is not limited to the time when the mold 1 is assembled. For example, the seal member 9 may be disposed after the filling of the porous concrete 3 and before the carbonation. The supply pipe 6 and the discharge pipe 7 may be inserted during or after the filling of the porous concrete 3. The supply pipe 6 and the discharge pipe 7 are not limited to steel pipes, and may be PVC pipes. Further, when injecting the solidified material, the discharge pipe 7 may be used in addition to the supply pipe 6. Only the discharge pipe 7 may be used for injecting the solidifying material.

Next, to confirm the effect of absorbing CO ₂ in the concrete block with recycled aggregate obtained by carbonation. Specifically, a block type test body of 1 m × 1 m × 1 m was made of concrete, and the CO ₂ emission amount at the time of manufacturing the block was estimated. The trial calculation cases are the three cases shown in Table 3. Case 1 is a case where normal concrete is cured under standard water. Case 2 is a case in which ordinary concrete is carbonized and cured for 7 days in an environment of temperature 50 ° C., humidity 50%, and CO ₂ concentration 20%. Case 3 uses the blast furnace cement type B as the cement of the concrete blend used in Case 1, and changes the aggregate from ordinary aggregate to carbonized recycled aggregate. After molding as concrete, the same as Case 2 This is a case of carbonation curing for 7 days in the environment.

  Tables 4 and 5 show the composition of materials used and ordinary concrete, respectively.

The CO ₂ emission amount of each concrete in cases 1 to 3 was estimated. For the trial calculation of the CO ₂ emission amount, the CO ₂ emission basic unit (source: Japan Society of Civil Engineers Concrete Library 125) shown in Table 6 was used.

As for the concrete and aggregate has absorbed CO ₂ by carbonation curing, minus the CO ₂ absorption by them, was calculated CO ₂ emissions by the following equation.
CO ₂ emissions from concrete (kg / m ³ )
= (Total amount of CO ₂ emission of used materials kg / m ³ ) − (CO ₂ amount absorbed by concrete or aggregate kg / m ³ )

Based on the above, CO ₂ emissions in Case 1 are shown in Tables 5 and 6.
291 x 0.7666 + 788 x 0.0037 + 1065 x 0.0029
= Is estimated to 229.1kg / ^{m 3.}

Next, in calculating the CO ₂ emission amount in case 2, it is necessary to calculate the amount of CO ₂ absorbed by the concrete by the carbonation curing. Here, the area where the concrete absorbed CO ₂ by carbonation by carbonation curing for 7 days is 10 cm from the surface, and the volume of the part that absorbed CO ₂ is 27.1% in the entire carbonation part. Existence (volume of carbonized region: (1 m × 1 m × 1 m) − (0.9 m × 0.9 m × 0.9 m) = 0.271 m ³ ), CO ₂ absorption was 134.8 kg / m ³ It was. From this, the CO ₂ absorption amount in the block is 135 kg / m 3 × 27.1% = 36.5 kg / m ³ .

Based on the above, CO ₂ emissions in Case 2 are
It is estimated that 229.1-36.5 = 192.6 kg / m ³ .

The calculation of CO ₂ emissions in Case 3 takes into account the CO ₂ emissions in the concrete mix using blast furnace cement type B and the CO ₂ amount absorbed by the regenerated aggregate through carbonation curing, and further, the carbon dioxide after molding. It is necessary to calculate the amount of CO ₂ absorbed by the concrete due to chemical curing.

From Tables 5 and 6, the total amount of CO ₂ emissions of materials used in the concrete composition of Case 3 is
291 x 0.4587 + 707 x 0.0037 + 965 x 0.0029
= 138.9 kg / m ³ .

Here, as shown in Table 7, the amount of CO ₂ absorbed by the regenerated aggregate by carbonation curing is aggregate weight × 7.8% in the case of RS, and aggregate weight × 8.5% in the case of RG. there were. From this, the amount of CO ₂ absorbed by the aggregate in case 3 is shown in Tables 5 and 7.
707 × 7.8% + 965 × 8.5% = 137.2 kg / m ³

Further, in the carbonation curing for 7 days performed after the concrete molding in Case 3, the area where the concrete absorbed CO ₂ by carbonation was 10 cm from the surface as in Case 2. From this, the amount of CO ₂ absorbed in the block is
135kg / ^{m 3} × 27.1% = the 36.5 kg / ^{m 3.}

Based on the above, CO ₂ emissions in Case 3 are
It is estimated that 138.9−36.5−137.2 = −34.8 kg / m ³ .

Table 8 shows the results of the trial calculation of CO ₂ emissions in cases 1 to 3. According to the present invention, it is possible to make the CO ₂ emission amount negative.

  DESCRIPTION OF SYMBOLS 1,1A ... Formwork, 1a, 1b, 1c ... Opening, 2 ... Parts, 3 ... Porous concrete, 6, 6A, 6a, 6b, 6c ... Supply pipe, 7 ... Discharge pipe, 9 ... Seal member, 11 ... Cement Milk (solidification material), 12 ... wave-dissipating block (concrete product).

Claims (6)

Filling at least one material of porous concrete, recycled aggregate, concrete block, and solidified material mainly composed of industrial by-products including blast furnace slag or fly ash into a mold having an opening;
Supplying carbon dioxide-containing gas into the mold through a supply pipe inserted from the opening to carbonate the at least one material;
Filling the voids in the region filled with the at least one material with a solidifying material containing cement and solidifying the voids. The mold is an assembly of a plurality of parts,
The method for producing a concrete product according to claim 1, further comprising a step of disposing a sealing member for enhancing airtightness in the formwork between the parts before the carbonating step. .   The method for producing a concrete product according to claim 1 or 2, wherein in the step of filling and solidifying the solidifying material, the solidifying material is injected using the supply pipe. Before the carbonating step, the method includes a step of inserting a discharge pipe for discharging exhaust gas from the mold and the supply pipe through the opening.
In this step, the length of the supply pipe in the mold is longer than the length of the discharge pipe in the mold. The concrete product according to any one of claims 1 to 3, Production method. The mold has a plurality of the openings,
5. The carbon dioxide-containing gas is supplied to a plurality of locations in the mold through the supply pipes inserted into the plurality of openings in the carbonation step. A method for producing a concrete product according to one item.   The heavy metal aggregate is used as the aggregate of the porous concrete or as the recycled aggregate in the step of filling the at least one kind of material. A method for manufacturing concrete products.

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