Concrete raw material and method for producing the concrete raw material

Abstract

To provide concrete raw material transportable in a usable state on site and free from the need of measuring an additive on site, and a method for producing concrete raw material.SOLUTION: Concrete raw material comprises: a bag body in which an opening part is formed at the upper part and an exhaust port is formed at the bottom part; opening-closing means capable of opening and closing the exhaust port; a hanging rope fitted to the back body in a state in which the exhaust port is located at the lower part and pulled up without clogging the exhaust port; a concrete aggregate stored in the lower part of the bag body and at least comprising granules and particulates; cement stored in the bag body so as not to come in direct contact with the concrete aggregate at the upper part of the aggregate via a water dissolution member; and an additive stored in the bag body so as not to come in direct contact with the concrete aggregate.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a concrete mix that can be transported to facilitate the production of ready mixed concrete on site, and to a method for producing the concrete mix. [Background technology]

[0002] Conventionally, ready mixed concrete used at construction sites is produced at a ready mixed concrete plant and then transported to the construction site. This has the drawback that the quality of the ready mixed concrete deteriorates over the transportation time. In addition, since the ready mixed concrete contains added water, it is heavy and the transportation efficiency is poor.

[0003] In order to eliminate this drawback, the present inventor has invented "a concrete raw material comprising a concrete aggregate storage bag having an opening at the top and a discharge outlet at the center of the bottom, opening and closing means for opening and closing the discharge outlet of the concrete aggregate storage bag, a hanging rope attached to the concrete aggregate storage bag so that the concrete aggregate storage bag can be hoisted with the discharge outlet located at the bottom and without blocking the discharge outlet, a predetermined amount of concrete aggregate stored in the concrete aggregate storage bag, and a predetermined amount of cement stored in a water-soluble member that dissolves in water and is large enough to be discharged from the discharge outlet within the concrete aggregate storage bag in which the concrete aggregate is stored" (Patent Document 1).

[0004] However, although such concrete materials can be used as is on-site, when additives such as coal ash are added to the ready mixed concrete being produced, the additives must be measured and added to the concrete material being mixed on-site, which is time-consuming. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2015-98121 A Summary of the Invention [Problem to be solved by the invention]

[0006] In view of the above-mentioned conventional drawbacks, the present invention has an object to provide a concrete raw material and a method for manufacturing a concrete raw material that can be transported in a state that can be used on site and does not require measuring additives on site.

[0007] The above and other objects and novel features of the present invention will become more fully apparent from the following description taken in conjunction with the accompanying drawings. However, the drawings are for illustrative purposes only and are not intended to limit the technical scope of the present invention. [Means for solving the problem]

[0008] In order to achieve the above object, the concrete raw material of the present invention comprises a bag body having an opening formed at the top and a discharge outlet formed at the bottom, an opening / closing means for opening and closing the discharge outlet, a hanging rope attached to the bag body so that the bag body can be hoisted with the discharge outlet located at the bottom and without blocking the discharge outlet, concrete aggregate that is stored in the lower part of the bag body and contains at least powdery or granular matter, cement that is stored in the bag body above the concrete aggregate via a water-soluble member so as not to come into direct contact with the aggregate, and an additive that is stored in the bag body so as not to come into direct contact with the concrete aggregate. The concrete aggregate is characterized in that it comprises fine aggregate having a small particle size stored in the lower part of the bag body, and coarse aggregate having a larger particle size than the fine aggregate stored above the fine aggregate. In the above configuration, the water-soluble member is formed in a bag shape, and at least one water-soluble member is stored above the concrete aggregate with the cement and the additives filled inside. The weight of the additives stored in the bag body is preferably 0.1% to 20% of the weight of the cement.

[0009] The method for producing concrete raw materials of the present invention includes an aggregate storing step of storing concrete aggregate including powder or granules in the lower part of the storing part of the bag body, a cement storing step of storing cement on the aggregate via a water-soluble member so as not to come into direct contact with the concrete aggregate, and an additive storing step of storing additives on the concrete aggregate via the water-soluble member so as not to come into direct contact with the concrete aggregate. the aggregate storing step includes a fine aggregate storing step of storing a predetermined amount of fine aggregate in the lowermost part of the storing portion of the bag body, and a coarse aggregate storing step of storing a predetermined amount of coarse aggregate on the upper part of the fine aggregate stored in the fine aggregate storing step. .

[0010] In the above configuration, the water-soluble member is formed in a bag shape, and at least one of the water-soluble members is stored on the upper part of the concrete aggregate with the cement and the additives filled therein.Furthermore, the weight of the additives stored in the bag body in the additive storing step is 0.1% to 20% of the weight of the cement.Note that the following dependent claim can be based on the preceding dependent claim as it is. Effect of the Invention

[0011] As is clear from the above description, the present invention provides the following effects. (1) Independent claims (claims 1 and Claim 4 In each of the inventions described in (1), not only cement as a powdered material but also additives including powdered or granular materials are stored in the bag body (concrete aggregate storage bag), so there is no need to measure and add additives on-site, and ready-mix concrete according to the purpose can be easily produced. (2) In addition, the powdered cement and additives containing powdered or granular materials are stored through a water-soluble material such as a water-soluble film so as not to come into direct contact with the aggregate, so that contact with moisture during storage and transportation can be reliably prevented, and therefore unintentional reaction between cement and water can be prevented. (3) Since the fine aggregate and the coarse aggregate are stored in the concrete aggregate storage bag so as to overlap from below, contact between the water-soluble material containing cement and the fine aggregate can be reliably prevented. Therefore, it is possible to prevent direct contact between the fine aggregate, which has a high water retention capacity and is likely to contain moisture, and the water-soluble component. (4) Claims 2 and 5 The inventions described in (1) to ( 4 ) and also makes it easy to store cement and additives. (5) Furthermore, by storing a unit amount of cement in the water-soluble components in advance, it is only necessary to adjust the number of water-soluble components storing cement according to the amount of aggregate, making the work easier. (6) When a plurality of bag-shaped water-soluble members are used, the size of each water-soluble member is small, so that the water-soluble members can be discharged smoothly without getting caught in the discharge port. (7)Furthermore, Claims 3 and 6 Each of the inventions described above can obtain the same effects as those of the above (1) to (6), and can also produce ready mixed concrete appropriately depending on the purpose. [Brief description of the drawings]

[0012] 1 to 7 are explanatory diagrams showing a first embodiment of the present invention. 8 to 10 are explanatory diagrams showing a second embodiment of the present invention. 11 to 13 are explanatory diagrams showing a third embodiment of the present invention. 14 to 16 are explanatory diagrams showing a fourth embodiment of the present invention. [Figure 1] FIG. 2 is a front view of the concrete raw material showing the first embodiment. [Diagram 2] 1A and 1B are longitudinal sectional views of a concrete raw material showing a first embodiment (including enlarged schematic sectional views of a state in which the bottom of a bag body is closed and a state in which the bottom is opened). [Diagram 3] An explanatory diagram of a concrete aggregate storage bag. [Figure 4] FIG. 2 is a process diagram of a method for producing a concrete raw material according to the first embodiment. [Diagram 5] An explanatory diagram of the aggregate storage process. [Figure 6] FIG. 2 is an explanatory diagram of the cement storage process and the additive storage process. [Figure 7] FIG. 13 is an explanatory diagram of the state of discharging into a hopper. [Figure 8]FIG. 6 is a longitudinal sectional view of a concrete raw material showing a second embodiment. [Figure 9] FIG. 4 is a process diagram of a method for producing a concrete raw material according to a second embodiment. [Figure 10] FIG. 2 is an explanatory diagram of the cement storage process and the additive storage process. [Figure 11] FIG. 11 is a longitudinal sectional view of a concrete raw material showing a third embodiment. [Figure 12] FIG. 11 is a process diagram showing a method for producing a concrete raw material according to a third embodiment. [Figure 13] FIG. 2 is an explanatory diagram of the cement storage process and the additive storage process. [Figure 14] FIG. 13 is a longitudinal sectional view of a concrete raw material showing a fourth embodiment. [Figure 15] FIG. 11 is a process diagram showing a method for producing a concrete raw material according to a fourth embodiment. [Figure 16] FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the embodiments shown in the drawings. In a first embodiment for carrying out the present invention shown in Figs. 1 to 7, reference numeral 1 denotes a concrete raw material of the present invention which is transported by truck or the like from a concrete aggregate factory to a construction site where ready-mix concrete is to be used.

[0014] As shown in Figs. 1 and 2, the concrete raw material 1 is composed of a bag body (concrete aggregate storage bag) 5 having an opening 2 formed at the top and a discharge section 4 serving as a discharge outlet 3 formed at the center of the bottom, a rope 6 having both ends 6a, a part 6b of the middle part 6b excluding 6a sewn and fixed to the outer periphery of the discharge section 4 as an opening / closing means 6 for opening and closing the discharge outlet 3 of the concrete aggregate storage bag 5, a plurality of hanging ropes 7 having looped upper parts attached by sewing or the like to both sides of the concrete aggregate storage bag 5 in a U-shape so that the concrete aggregate storage bag 5 can be lifted with the discharge outlet 3 of the concrete aggregate storage bag 5 located at the bottom and without blocking the discharge outlet 3, aggregate 9 including powdery or granular material stored in the lower part of a storage section 8 inside the concrete aggregate storage bag 5, a predetermined amount of cement 11 as a powdery material stored above the aggregate 9 via a water-soluble member 10 so as not to come into direct contact with the aggregate 9, and a predetermined amount of additive 12 stored so as not to come into direct contact with the aggregate 9.

[0015] In this embodiment, the water-soluble member 10 is formed in a bag shape having a size that allows it to be discharged from the discharge port 3, and the bag-shaped water-soluble member 10 is filled with the cement 11 and the additive 12 in a sealed state.

[0016] As shown in Figure 3, the concrete aggregate storage bag 5 is a bag-shaped member with a storage section 8 inside, and is made of a material that is strong enough to be transported while containing concrete aggregate, etc.

[0017] A discharge outlet 3 is formed in the approximate center of the bottom of the concrete aggregate storage bag 5, and a cylindrical discharge part 4 is provided so as to communicate with this discharge outlet 3. This cylindrical discharge part 4 is fixed to the concrete aggregate storage bag 5 by gluing or the like so that its upper end part communicates with the approximate center of the bottom of the concrete aggregate storage bag 5, and concrete aggregate 9 and bag-shaped water-soluble member 10 containing cement 11 and additives 12 are discharged from the other open end part through the discharge outlet 3 at the lower end part into a ready-mix concrete manufacturing device or the like.

[0018] In its normal state (when concrete aggregate 9, etc. are stored), the cylindrical discharge section 4 is kept in a folded state and closed by the opening / closing means 6, and when in use, the folded state is released by undoing the rope 6 which constitutes the opening / closing means 6, and the concrete aggregate 9, etc. are discharged from the discharge section 4 (see, for example, Figures 2 and 7).

[0019] After the concrete aggregate 9, cement 11, and additives 12 have been stored in the opening 2, the opening 2 is closed with a rope or the like.

[0020] In this embodiment, the concrete aggregate 9 is composed of fine aggregate 13 having a small particle size and coarse aggregate 14 stored above the fine aggregate and having a larger particle size than the fine aggregate. The fine aggregate 13 is stored at the bottom of the storage section 8 inside the concrete aggregate storage bag 5, and the coarse aggregate 14 is stored so as to be piled up on top of the fine aggregate 13.

[0021] The fine aggregate 13 is a small particle size aggregate such as sand or artificial fine aggregate, which passes through a 10 mm sieve and contains 85% or more by weight of particles of 5 mm or less.

[0022] On the other hand, the coarse aggregate 14 is mainly gravel or artificial coarse aggregate with a relatively large particle size, and 85% or more by weight of aggregates with a particle size of 5 mm or more are used. This coarse aggregate 14 is stored in the concrete aggregate storage bag 5 so as to be layered on top of the fine aggregate 13.

[0023] This coarse aggregate 14 may contain up to 15% particles of the same size as the fine aggregate 13, but since the proportion of aggregate with a small particle size is small, the water retention capacity is low. Also, since the particle size of the coarse aggregate 14 is relatively large, the particles of the same size as the fine aggregate 13 fall downward through the gaps between the coarse aggregates 14 and do not come into contact with the water-soluble material 10 containing the cement 11 and additives 12 stored on top of the coarse aggregate 14.

[0024] In addition, since the cement 11 and the additives 12 are stored using the water-soluble member 10 so as not to come into direct contact with the coarse aggregate 14, the cement 11 and the additives 12 do not fall through gaps in the coarse aggregate 14 and do not come into contact with the fine aggregate 13. This makes it possible to more reliably prevent the cement 11 and the additives 12 from reacting with moisture and causing chemical reactions such as solidification.

[0025] The water-soluble member 10 is made of a material that dissolves in water, for example, a water-soluble film, such as Hi-Selon (trade name of Nippon Gosei Kagaku Co., Ltd.) S type, which is resistant to alkali, and is formed in a bag shape in this embodiment.

[0026] When a predetermined amount of cement 11 and additive 12 are stored in this bag-shaped water-soluble member 10 and made to be in a sealed state, it may be possible to seal it with a string 15 made of the same material (such as water-soluble resin), or by fusing or welding, etc.

[0027] The additives 12 are admixtures (admixtures or additives) added for the purpose of increasing the strength of concrete, accelerating the solidification rate, etc., and examples of such additives include inorganic substances such as silica fume, coal ash, nitrates, sulfates, carbonates, alumina, limestone, rice husk ash, etc. Appropriate additives 12 are selected in consideration of the specifications of the ready-mix concrete to be manufactured.

[0028] The weight of the additive 12 to be added is 0.1% to 20% by weight of the cement, preferably 0.1% to 2% by weight, and more preferably about 1% by weight. In this embodiment, the additive 12 is stored in a bag-shaped water-soluble member 10 together with the cement 11 .

[0029] As shown in FIG. 4, the method 16 for producing concrete raw materials of the present invention is composed of an aggregate storing step 17 for storing a predetermined amount of aggregate 9 containing powder or granular material in the lower part of the storage section 8 of the concrete aggregate storage bag 5, a cement storing step 18 for storing a predetermined amount of cement 11 on top of the aggregate 9 stored in the aggregate storing step 17 via a water-soluble member 10 so as not to come into direct contact with the aggregate 9, and an additive storing step 19 for storing a predetermined amount of additive 12 on top of the aggregate 9 stored in the aggregate storing step 17 via the water-soluble member 10 so as not to come into direct contact with the aggregate 9.

[0030] In this embodiment, the aggregate storing step 17 is composed of a fine aggregate storing step 20 and a coarse aggregate storing step 21, and the fine aggregate storing step 20 is performed first, followed by the coarse aggregate storing step 21.

[0031] In the fine aggregate storage process 20, as shown in Figure 4, a predetermined amount of fine aggregate 13 is weighed out and stored in the lowermost part of the storage section 8 inside the concrete aggregate storage bag 5, with the bottom discharge outlet 3 blocked by an opening and closing means, and the fine aggregate 13 is filled (stored) so that it covers the bottom side of the storage section 8 of the concrete aggregate storage bag 5.

[0032] The coarse aggregate storage process 21, as shown in Figure 6, is a process of storing a predetermined amount of the coarse aggregate 14 in a layered manner on top of the fine aggregate 13. By storing the coarse aggregate 14 in this manner so as to cover the top of the fine aggregate 13, the fine aggregate 13, which is relatively difficult to dry, is prevented from coming into direct contact with the bag-shaped water-soluble material 10 containing the cement 11 and additives 12.

[0033] 7, in the cement storing step 18, a predetermined amount of cement is filled (stored) in the bag-shaped water-soluble member 10, which is then sealed, and a predetermined number of bag-shaped water-soluble members 10 containing cement 11 are placed and stored on the top surface of the coarse aggregate 14; in this embodiment, one bag-shaped water-soluble member 10. The bag-shaped water-soluble member 10 is formed to a size that allows it to pass through the discharge port 3 and discharge portion 4 while containing the cement 11.

[0034] In this embodiment, the additive 12 is also stored in the concrete aggregate storage bag 5 together with the cement 11 in a sealed state in the bag-shaped water-soluble member 10. Therefore, the cement storing step 18 and the additive storing step 19 are performed in parallel, and when a predetermined amount of cement 11 is filled (stored) in the bag-shaped water-soluble member 10, a predetermined amount of the additive is also stored, and then the water-soluble member 10 is sealed.

[0035] The water-soluble member 10 containing the cement 11 and additives 12 is placed on the top surface of the coarse aggregate 14, and the cement containing step 18 and additives containing step 19 are completed. After the cement storing step 18 and the additive storing step 19 are completed, the opening 2 of the concrete aggregate storing bag 5 is appropriately closed.

[0036] When using the concrete raw material 1 configured in this manner, as shown in FIG. 7, the concrete aggregate storage bag 5 is hung by the hanging rope 7 attached to the hook 23 of the crane 22, the discharge section 4 is positioned above the hopper 25 of the concrete mixer 24, and the rope 6 serving as the opening / closing means 6 is released to open the discharge outlet 3, whereby the fine aggregate 13, coarse aggregate 14, and the cement 11 and additives 12 sealed in the bag-shaped water-soluble material 10 in the concrete aggregate storage bag 5 are dropped and supplied into the hopper 25 from the discharge outlet 3 of the discharge section 4.

[0037] Thereafter, a measured amount of water is added to the fine aggregate 13, coarse aggregate 14, and the cement 11 and additives 12 sealed in the bag-shaped water-soluble members 10 supplied into the concrete mixer 24, and they are mixed; the water-soluble members 10 are dissolved by the added water, and the fine aggregate 13, coarse aggregate 14, and the cement 11 and additives 12 sealed in the bag-shaped water-soluble members 10 are mixed together, and ready-mix concrete according to the purpose is produced.

[0038] [Different modes for carrying out the invention] Next, different embodiments for carrying out the present invention will be described with reference to Figures 8 to 15. In describing these different embodiments for carrying out the present invention, the same components as those in the first embodiment for carrying out the present invention will be designated by the same reference numerals, and duplicated descriptions will be omitted.

[0039] The second embodiment for carrying out the present invention shown in Figures 8 to 10 mainly differs from the first embodiment for carrying out the present invention in that small bag-shaped water-soluble members 10A containing unit weights of cement 11 and additives 12 are used, and a plurality of these bag-shaped water-soluble members 10A are stored in a concrete aggregate storage bag 5. Even with such concrete raw material 1A and a concrete raw material manufacturing method 16A which carries out a cement storage step 18A and an additive storage step 19A in which such bag-shaped water-soluble members 10A are stored, the same effects as those of the first embodiment for carrying out the present invention can be obtained.

[0040] In this embodiment, the cement 11 and the additive 12 are mixed in the water-soluble material 10A, but for example, a water-soluble material 10A containing only the cement 11 and a water-soluble material 10A containing only the additive 12 may be prepared separately and each may be stored in the concrete aggregate storage bag 5.

[0041] The third embodiment for carrying out the present invention shown in Figures 11 to 13 mainly differs from the first embodiment for carrying out the present invention in that the cement 11 and additives 12 are stored on top of the coarse aggregate 14 via a sheet-like water-soluble member 11B. Even if a concrete raw material manufacturing method 16B is used in which the cement storing step 18B and the additives storing step 19B are performed using such concrete raw material 1B and such water-soluble member 10B so that the coarse aggregate 14 does not come into contact with the cement 11 and additives 12, the same effects as those of the first embodiment for carrying out the present invention can be obtained.

[0042] The fourth embodiment for carrying out the present invention shown in Figures 14 and 15 mainly differs from the second embodiment for carrying out the present invention in that a bag-shaped waterproof storage member 26 formed of a waterproof sheet is used that can store one or more water-soluble members 10A each containing a predetermined amount of cement 11, and the water-soluble members 10A each containing cement 11 and additives 12 are stored in this waterproof storage member 26, and concrete aggregate 9A in which fine aggregate 13 and coarse aggregate 14 are used. Even if such concrete raw material 1C or concrete aggregate 9A is stored in concrete aggregate storage bag 5, and a cement storage step 18C and an additive storage step 19C are performed to store cement 11 and additives in waterproof storage member 26, the same effects as those of the first embodiment for carrying out the present invention can be obtained.

[0043] This waterproof storage member 26 is fixed to the upper inner wall surface of the concrete aggregate storage bag 5 by sewing or its upper part is tied with a string, which is fixed to the rope 6 that fastens the upper part of the concrete aggregate storage bag 5, so that the waterproof storage member 26 will not be discharged from the concrete aggregate storage bag 5 when the concrete aggregate 9A is discharged from the discharge opening 3 of the concrete aggregate storage bag 5. The lower part of the waterproof storage member 26 is formed with an open supply section 27, and this lower part is normally folded up to be in a closed state.

[0044] When the concrete aggregate 9A is discharged from the discharge outlet 3, the lower part of the waterproof storage member 26, which is normally folded, straightens out, opening the supply section 27, and the water-soluble member 10A containing the cement 11 and the additives 12 are supplied to the concrete aggregate storage bag 5 and then discharged from the discharge outlet 3 to a hopper 25, etc.

[0045] In this embodiment, the additive 12 is stored as is in the waterproof storage member 26, but it may also be stored in the waterproof storage member 26 together with the cement 11 or separately from the cement 11 in a water-soluble member 10A.

[0046] In addition, in this embodiment, the cement and additives 12 stored in the water-soluble member 10A are stored in the waterproof storage member 26, but the cement 11 and the like stored in the small water-soluble member 10A may also be stored in a large bag-shaped water-soluble member having a similar shape to the waterproof storage member 26. [Industrial Applicability]

[0047] The present invention is utilized in industries such as those producing concrete raw materials. [Explanation of symbols]

[0048] 1, 1A, 1B, 1C: Concrete raw materials, 2: Opening, 3: Outlet, 4: Discharge part, 5: Bag body (concrete aggregate storage bag), 6: opening and closing means; 7: hanging rope; 8: Storage section, 9, 9A: Concrete aggregate 10, 10A, 10B: water-soluble material, 11: cement, 12: Additives, 13: Fine aggregate, 14: coarse aggregate, 15: string, 16, 16A, 16B, 16C: Method for producing concrete raw materials; 17, 17A: Aggregate storage process; 18, 18A, 18B, 18C: Cement storage process; 19, 19A, 19B, 19C: Additive storage process, 20: Fine aggregate storage process; 21: Coarse aggregate storage process; 22: Crane, 23: Hook, 24: Concrete mixer, 25: Hopper, 26: waterproof storage member; 27: supply section.

Claims

1. a bag body having an opening at the top and a discharge outlet at the bottom; an opening / closing means for opening and closing the discharge outlet; a hanging rope attached to the bag body so that the bag body can be hoisted with the discharge outlet located at the bottom and without blocking the discharge outlet; concrete aggregate stored in the lower part of the bag body and including at least powdery or granular material; cement stored in the bag body above the concrete aggregate via a water-soluble member so as not to come into direct contact with the concrete aggregate; and additives stored in the bag body so as not to come into direct contact with the concrete aggregate, the concrete aggregate comprising fine aggregate having a small particle size stored in the lower part of the bag body and coarse aggregate stored above the fine aggregate and having a larger particle size than the fine aggregate.

2. The concrete raw material according to claim 1, characterized in that the water-soluble member is formed in a bag shape, and at least one water-soluble member is stored on top of the concrete aggregate with the cement and the additives filled inside.

3. 3. The concrete raw material according to claim 1, wherein the weight of the additive contained in the bag body is 0.1% to 20% of the weight of the cement.

4. The method for producing concrete raw materials includes an aggregate storing step of storing concrete aggregate including powder or granules in the lower part of a storing section of a bag body, a cement storing step of storing cement on top of the concrete aggregate via a water-soluble member so as not to come into direct contact with the concrete aggregate, and an additive storing step of storing additives on top of the concrete aggregate via the water-soluble member so as not to come into direct contact with the concrete aggregate, the aggregate storing step comprising a fine aggregate storing step of storing a predetermined amount of fine aggregate in the lowermost part of the storing section of the bag body, and a coarse aggregate storing step of storing a predetermined amount of coarse aggregate on top of the fine aggregate stored in the fine aggregate storing step.

5. 5. The method for producing a concrete raw material according to claim 4, wherein the water-soluble member is formed in a bag shape, and at least one of the water-soluble members is stored on top of the concrete aggregate with the cement and the additives filled therein.

6. 6. The method for manufacturing a concrete raw material according to claim 4, wherein the weight of the additive contained in the bag body in the additive containing step is 0.1% to 20% of the weight of the cement.

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