CN113896469A - Large-volume high-strength concrete - Google Patents
Large-volume high-strength concrete Download PDFInfo
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- CN113896469A CN113896469A CN202111360218.4A CN202111360218A CN113896469A CN 113896469 A CN113896469 A CN 113896469A CN 202111360218 A CN202111360218 A CN 202111360218A CN 113896469 A CN113896469 A CN 113896469A
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- concrete
- raw materials
- mixing
- strength concrete
- strength
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- 239000011372 high-strength concrete Substances 0.000 title claims abstract description 23
- 239000002994 raw material Substances 0.000 claims abstract description 35
- 239000004568 cement Substances 0.000 claims abstract description 20
- 239000004576 sand Substances 0.000 claims abstract description 13
- 239000000843 powder Substances 0.000 claims abstract description 11
- 239000010881 fly ash Substances 0.000 claims abstract description 10
- 229910052500 inorganic mineral Inorganic materials 0.000 claims abstract description 8
- 239000011707 mineral Substances 0.000 claims abstract description 8
- 239000004575 stone Substances 0.000 claims abstract description 8
- 239000004567 concrete Substances 0.000 claims description 54
- 238000002156 mixing Methods 0.000 claims description 40
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 35
- 239000003638 chemical reducing agent Substances 0.000 claims description 14
- 239000000654 additive Substances 0.000 claims description 10
- 230000000996 additive effect Effects 0.000 claims description 10
- 239000000203 mixture Substances 0.000 claims description 8
- 238000000034 method Methods 0.000 claims description 7
- 238000005096 rolling process Methods 0.000 claims description 7
- 238000012423 maintenance Methods 0.000 claims description 6
- 238000002360 preparation method Methods 0.000 claims description 6
- 238000010276 construction Methods 0.000 claims description 5
- 230000008569 process Effects 0.000 claims description 2
- 239000004566 building material Substances 0.000 abstract description 2
- 230000035939 shock Effects 0.000 abstract description 2
- 239000000463 material Substances 0.000 description 9
- 230000036571 hydration Effects 0.000 description 4
- 238000006703 hydration reaction Methods 0.000 description 4
- 229910000831 Steel Inorganic materials 0.000 description 2
- 238000005260 corrosion Methods 0.000 description 2
- 238000001514 detection method Methods 0.000 description 2
- 230000001603 reducing effect Effects 0.000 description 2
- 239000010959 steel Substances 0.000 description 2
- 230000009471 action Effects 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 230000003487 anti-permeability effect Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 230000001276 controlling effect Effects 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000003111 delayed effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000003292 glue Substances 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 239000003973 paint Substances 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B28/00—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B28—WORKING CEMENT, CLAY, OR STONE
- B28B—SHAPING CLAY OR OTHER CERAMIC COMPOSITIONS; SHAPING SLAG; SHAPING MIXTURES CONTAINING CEMENTITIOUS MATERIAL, e.g. PLASTER
- B28B11/00—Apparatus or processes for treating or working the shaped or preshaped articles
- B28B11/24—Apparatus or processes for treating or working the shaped or preshaped articles for curing, setting or hardening
- B28B11/245—Curing concrete articles
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B28—WORKING CEMENT, CLAY, OR STONE
- B28C—PREPARING CLAY; PRODUCING MIXTURES CONTAINING CLAY OR CEMENTITIOUS MATERIAL, e.g. PLASTER
- B28C5/00—Apparatus or methods for producing mixtures of cement with other substances, e.g. slurries, mortars, porous or fibrous compositions
- B28C5/003—Methods for mixing
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2201/00—Mortars, concrete or artificial stone characterised by specific physical values
- C04B2201/50—Mortars, concrete or artificial stone characterised by specific physical values for the mechanical strength
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Ceramic Engineering (AREA)
- Structural Engineering (AREA)
- Mechanical Engineering (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Inorganic Chemistry (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- Curing Cements, Concrete, And Artificial Stone (AREA)
Abstract
The invention discloses a large-volume high-strength concrete, and belongs to the technical field of building materials. The large-volume high-strength concrete comprises the following raw materials in parts by weight: 400-450 kg/m cement3620-660 kg/m of sand31000-1050 kg/m stone365-70 kg/m mineral powder354-58 kg/m of fly ash3. The invention has high strength, excellent impermeability and excellent shock resistance.
Description
Technical Field
The invention relates to the technical field of building materials, in particular to large-volume high-strength concrete.
Background
In the prior art, concrete is prepared by mixing cement, sand, stones, water and a water reducing agent. The concrete has the advantages of high compressive strength, easily obtained materials, easy molding and low price, and can be combined with steel materials to prepare various bearing members; however, the fatal defects of the alloy are low tensile strength, large brittleness, easy cracking and poor toughness; therefore, the bearing capacity of the concrete structure is reduced, the service life is shortened, and the hidden danger of various disasters and accidents is formed. In particular, the material has poor impact resistance and is easy to brittle fracture and fall off under the action of impact load.
Disclosure of Invention
The invention aims to provide large-volume high-strength concrete which has excellent impact resistance and can meet the requirements of structures such as bridges, roads, dams, tunnels and the like with large impact load; the problem of among the prior art, bearing capacity, the impact property of concrete are poor is solved.
In order to achieve the purpose, the invention adopts the following technical scheme:
the large-volume high-strength concrete comprises the following raw materials in parts by weight:
400-450 kg/m cement3620-660 kg/m of sand31000-1050 kg/m stone365-70 kg/m mineral powder354-58 kg/m of fly ash3。
In some embodiments, the composition comprises the following raw materials by weight:
cement 434kg/m3645kg/m of sand31022kg/m of pebbles367kg/m of mineral powder356kg/m of fly ash3。
In some embodiments, the concrete uses a C60P8 mix ratio.
In some embodiments, the composition further comprises the following raw materials in parts by weight:
8.800-9.000 kg/m of additive3。
In some embodiments, the admixture comprises, by weight: 8.912kg/m3。
In some embodiments, the admixture is a high performance water reducer.
In some embodiments, the water-to-cement ratio of the concrete is 0.28 to 0.32.
A preparation method of large-volume high-strength concrete comprises the following steps:
s1, calculating the mixing ratio:
checking the water content of the raw materials, and calculating the construction mix proportion matched with the current water content according to the water content of the raw materials;
s2, mixing raw materials:
the raw materials are sent into a mixing station, and the mixing station mixes the raw materials according to the proportion.
In some embodiments, in step S2 raw material blending, mixing is performed in the following order:
firstly, mixing cement, sand, pebbles, water, mineral powder and fly ash, and then adding a water reducing agent for mixing.
In some embodiments, the mixing temperature in the step S2 of mixing the raw materials is 20 to 30 ℃.
In some embodiments, the method further comprises the steps of:
s3, sample comparison:
every 100m3Concrete, three groups of samples are taken;
one group is subjected to the same curing (curing under the same condition as the on-site concrete), and the other group is subjected to standard curing (sent into a standard curing room);
s4, checking the result:
conveying the cured concrete into a laboratory for rolling, wherein the rolling result is greater than 60MPA, and the concrete is qualified;
one group of standard maintenance test blocks is subjected to a 3-day impermeability test, and if the impermeability grade is achieved and the strength is qualified, the standard maintenance test blocks are qualified.
Compared with the prior art, the invention provides a large-volume high-strength concrete which has the following beneficial effects:
1. according to the invention, the concrete has excellent impact resistance, and compared with common concrete, the concrete has higher strength and can bear higher pressure; and the water-based paint has excellent impermeability, and is very suitable for construction in places such as pressure-bearing reservoirs, underground tunnel reservoirs and the like.
2. In the preparation process, the mixing sequence and the mixing temperature are controlled so as to further ensure and improve the performance of the concrete.
The parts not involved in the device are the same as or can be realized by the prior art, and the concrete has excellent impact resistance, high strength and excellent impermeability.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments.
The first embodiment is as follows:
the large-volume high-strength concrete comprises the following raw materials in parts by weight:
400-450 kg/m cement3620-660 kg/m of sand31000-1050 kg/m stone365-70 kg/m mineral powder354-58 kg/m of fly ash3。
Mineral powder and fly ash are added on the basis of cement, sand, stones and water to reduce hydration heat, improve later strength and improve the anti-permeability and anti-corrosion capability of the cement, sand, stones and water; and the workability of concrete mixture can be improved, the pumpability is enhanced, the creep is reduced, the hydration speed of the cementing material is delayed, and the setting time of the concrete is prolonged.
Meanwhile, the proportion of each raw material is accurately regulated and controlled, so that the functions and the interaction of the raw materials are fully exerted, and the excellent performance of the concrete is ensured.
Further, the feed also comprises the following raw materials in parts by weight:
8.800-9.000 kg/m of additive3。
Wherein the additive is a high-performance water reducing agent.
The water reducing agent can improve the workability of concrete, prolong the setting time and slow down the hydration and heat release speed of cement; meanwhile, the strength, the deformability and the impermeability of the concrete can be improved, the freeze-thaw resistance of the concrete can be improved, and the corrosion of steel bars in the concrete can be slowed down; thereby, the impact resistance of the concrete is further enhanced.
The concrete is prepared by using C60P8 mixing ratio; so as to ensure the compressive strength grade and the impermeability grade.
Furthermore, the water-cement ratio of the concrete is 0.28-0.32.
Different slump and compressive strength can be obtained by setting different water-cement ratios to adjust and match the requirements of actual engineering.
Example two:
the large-volume high-strength concrete comprises the following raw materials in parts by weight:
cement 434kg/m3645kg/m of sand31022kg/m of pebbles367kg/m of mineral powder356kg/m of fly ash3。
Further, the feed also comprises the following raw materials in parts by weight:
the admixture is 8.912kg/m3。
A preparation method of large-volume high-strength concrete comprises the following steps:
s1, calculating the mixing ratio:
and checking the water content of the raw materials, and calculating the construction mix proportion matched with the current water content according to the water content of the raw materials.
Therefore, high standardization and refinement are kept, and the product performance is fully ensured.
S2, mixing raw materials:
the raw materials are sent into a mixing station, and the mixing station mixes the raw materials according to the proportion.
Wherein, in the raw material mixing, the mixing is carried out according to the following sequence:
firstly, mixing cement, sand, pebbles, water, mineral powder and fly ash, and then adding a water reducing agent for mixing.
The mixing time can be reduced and the working efficiency can be improved by adopting a water reducing agent post-mixing method; meanwhile, the problem of poor adaptability of cement and a water reducing agent caused by frequent addition of new cement due to a small material bin of a mixing station can be avoided; the effect of the water reducing agent is improved, so that the concrete has higher strength, better impermeability and lower hydration heat.
Further, controlling the mixing temperature to be 20-30 ℃; when the temperature is too low, the water reducing agent is easy to crystallize and precipitate, and when the temperature is high, the water reducing agent is easy to deteriorate; the temperature range is controlled, and the water reducing agent can fully play a role so as to further improve the shock resistance of the concrete.
Wherein, still include the following step:
s3, sample comparison: every 100m3Concrete, three groups of samples are taken;
one group is subjected to cocultivation (curing under the same condition as that of on-site concrete), and the other group is subjected to standard curing (conveyed into a standard curing room).
S4, checking the result:
conveying the cured concrete into a laboratory for rolling, wherein the rolling result is greater than 60MPA, and the concrete is qualified;
one group of standard maintenance test blocks is subjected to a 3-day impermeability test, and if the impermeability grade is achieved and the strength is qualified, the standard maintenance test blocks are qualified.
According to the mass high-strength concrete and the preparation method thereof, an experimental group is arranged; the specific implementation process comprises the following steps:
1) firstly, various raw materials are respectively subjected to raw material detection tests so as to ensure that all the materials meet the requirements of specifications and proportions.
2) And measuring and determining the water content of the detected material so as to calculate the addition amount of water.
3) Adding other materials except the additive into a machine according to a ratio, or uniformly mixing the materials in a manual mixing mode; after being mixed uniformly, the admixture is added; wherein, the content of the additive is accurately controlled.
4) After the additive is added, continuously stirring uniformly; and pouring part of the concrete into a mould, and preparing a test mould according to the standard requirement.
5) And the test mold is removed after one day, and the test mold is placed in a curing room for curing.
6) And on the 7 th day and the 28 th day after the concrete mixing, respectively carrying out crushing and rolling tests, and observing whether the strength rise meets the requirements.
Three groups of water-glue ratio comparison groups are arranged, and the experimental results are as follows:
1) and under the condition that the water-gel ratio is 0.28:
the slump of the concrete is 185mm, and the compressive strength of the concrete after 7 days is detected to be 64.7 MPa; the compressive strength at 28 days was found to be 74.1 MPa.
2) And when the water-gel ratio is 0.30:
the slump of the concrete is 180mm, and the concrete is detected to be 59.9MPa in 7-day compressive strength; the compressive strength at 28 days was found to be 69.6 MPa.
3) And when the water-gel ratio is 0.32:
the slump of the concrete is 170mm, and the concrete is 55.0MPa after 7-day compressive strength detection; the compressive strength at 28 days was found to be 64.7 MPa.
Two groups of additive dosage comparison groups are arranged:
1) other components are unchanged, and the dosage of the admixture is less than 8.912kg/m3;
2) Other components are unchanged, and the dosage of the admixture is more than 8.912kg/m3。
The test results are as follows:
the first group, when the content of the additive is reduced, the water reducing effect is insufficient, so that the concrete lacks water and the reaction is insufficient; the strength of the mixed concrete is reduced and is expressed as dry, crisp and surface.
And in the second group, when the content of the additive is increased, the water reducing effect is too high, so that the concrete is over-hydrated and does not react sufficiently, and the strength of the mixed concrete is reduced, namely, the concrete is wet, soft and crisp.
According to the invention, the concrete has excellent impact resistance; compared with common concrete, the concrete has higher strength, can bear higher pressure and has excellent impermeability; the method is very suitable for construction in the positions with large impact load, such as a pressure-bearing reservoir, an underground tunnel reservoir and the like; in the preparation process, the mixing sequence and the temperature are controlled, so that the performance of the concrete is further ensured and improved.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and the inventive concepts thereof according to the present invention should be equivalent or changed within the scope of the present invention.
Claims (10)
1. The large-volume high-strength concrete is characterized by comprising the following raw materials in parts by weight:
400-450 kg/m cement3620-660 kg/m of sand31000-1050 kg/m stone365-70 kg/m mineral powder354-58 k of fly ashg/m3。
2. The mass high-strength concrete according to claim 1, which comprises the following raw materials in parts by weight:
cement 434kg/m3645kg/m of sand31022kg/m of pebbles367kg/m of mineral powder356kg/m of fly ash3。
3. A mass high strength concrete according to claim 1, wherein said concrete uses a C60P8 mix ratio.
4. The mass high-strength concrete according to claim 1, further comprising the following raw materials in parts by weight:
8.800-9.000 kg/m of additive3。
5. The mass high-strength concrete according to claim 4, wherein the admixture comprises the following components in parts by weight: 8.912kg/m3。
6. The mass high-strength concrete according to claim 4, wherein the admixture is a high-performance water reducing agent.
7. The mass high-strength concrete according to claim 1, wherein the water-to-cement ratio of the concrete is 0.28 to 0.32.
8. A preparation method of large-volume high-strength concrete according to any one of claims 1 to 7, characterized by comprising the following steps:
s1, calculating the mixing ratio:
checking the water content of the raw materials, and calculating the construction mix proportion matched with the current water content according to the water content of the raw materials;
s2, mixing raw materials:
the raw materials are sent into a mixing station, and the mixing station mixes the raw materials according to the proportion.
9. A method for preparing a mass high strength concrete according to claim 8, wherein in the step of mixing raw materials S2, the mixing is performed in the following order:
firstly, mixing cement, sand, stones, water, mineral powder and fly ash, and then adding a water reducing agent for mixing;
the mixing temperature of the raw materials is 20-30 ℃ in the mixing process.
10. A method of preparing a high-strength concrete of large volume according to claim 8, further comprising the steps of:
s3, sample comparison:
every 100m3Concrete, three groups of samples are taken;
one group is subjected to the same curing (curing under the same condition as the on-site concrete), and the other group is subjected to standard curing (sent into a standard curing room);
s4, checking the result:
conveying the cured concrete into a laboratory for rolling, wherein the rolling result is greater than 60MPA, and the concrete is qualified;
one group of standard maintenance test blocks is subjected to a 3-day impermeability test, and if the impermeability grade is achieved and the strength is qualified, the standard maintenance test blocks are qualified.
Priority Applications (1)
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CN202111360218.4A CN113896469A (en) | 2021-11-17 | 2021-11-17 | Large-volume high-strength concrete |
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CN202111360218.4A CN113896469A (en) | 2021-11-17 | 2021-11-17 | Large-volume high-strength concrete |
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Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN101549976A (en) * | 2009-05-18 | 2009-10-07 | 中铁隧道集团有限公司 | Concrete mixing proportion for deposition tube tunneltron segment |
CN103787628A (en) * | 2013-12-18 | 2014-05-14 | 中铁五局(集团)有限公司 | Preparation method of low-temperature early strength concrete for high cold permafrost region tunnel |
CN111548094A (en) * | 2020-05-28 | 2020-08-18 | 中交路桥建设有限公司 | Impervious concrete and proportioning method thereof |
CN112062521A (en) * | 2020-09-08 | 2020-12-11 | 天津市堃淏混凝土有限公司 | Large-volume concrete and preparation method thereof |
CN112266218A (en) * | 2020-11-06 | 2021-01-26 | 北京众和聚源混凝土有限公司 | High-strength concrete and preparation method thereof |
WO2021012937A1 (en) * | 2019-07-24 | 2021-01-28 | 桂林理工大学 | High-strength coral concrete and preparation method therefor |
-
2021
- 2021-11-17 CN CN202111360218.4A patent/CN113896469A/en active Pending
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN101549976A (en) * | 2009-05-18 | 2009-10-07 | 中铁隧道集团有限公司 | Concrete mixing proportion for deposition tube tunneltron segment |
CN103787628A (en) * | 2013-12-18 | 2014-05-14 | 中铁五局(集团)有限公司 | Preparation method of low-temperature early strength concrete for high cold permafrost region tunnel |
WO2021012937A1 (en) * | 2019-07-24 | 2021-01-28 | 桂林理工大学 | High-strength coral concrete and preparation method therefor |
CN111548094A (en) * | 2020-05-28 | 2020-08-18 | 中交路桥建设有限公司 | Impervious concrete and proportioning method thereof |
CN112062521A (en) * | 2020-09-08 | 2020-12-11 | 天津市堃淏混凝土有限公司 | Large-volume concrete and preparation method thereof |
CN112266218A (en) * | 2020-11-06 | 2021-01-26 | 北京众和聚源混凝土有限公司 | High-strength concrete and preparation method thereof |
Non-Patent Citations (1)
Title |
---|
严克凡等: "高强抗渗混凝土施工质量控制措施研究", 《居业》 * |
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Application publication date: 20220107 |