CN113149549A - Mass concrete and production method thereof - Google Patents
Mass concrete and production method thereof Download PDFInfo
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- CN113149549A CN113149549A CN202110350905.1A CN202110350905A CN113149549A CN 113149549 A CN113149549 A CN 113149549A CN 202110350905 A CN202110350905 A CN 202110350905A CN 113149549 A CN113149549 A CN 113149549A
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- 239000004567 concrete Substances 0.000 title claims abstract description 57
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 17
- 239000010881 fly ash Substances 0.000 claims abstract description 26
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 19
- 239000011398 Portland cement Substances 0.000 claims abstract description 17
- 239000004575 stone Substances 0.000 claims abstract description 17
- 239000004576 sand Substances 0.000 claims abstract description 15
- 239000002994 raw material Substances 0.000 claims abstract description 11
- 239000000654 additive Substances 0.000 claims abstract description 8
- 230000000996 additive effect Effects 0.000 claims abstract description 8
- 239000004568 cement Substances 0.000 claims description 23
- 238000006703 hydration reaction Methods 0.000 claims description 23
- 230000036571 hydration Effects 0.000 claims description 22
- 239000003638 chemical reducing agent Substances 0.000 claims description 13
- 239000002253 acid Substances 0.000 claims description 10
- HOOWDPSAHIOHCC-UHFFFAOYSA-N dialuminum tricalcium oxygen(2-) Chemical compound [O--].[O--].[O--].[O--].[O--].[O--].[Al+3].[Al+3].[Ca++].[Ca++].[Ca++] HOOWDPSAHIOHCC-UHFFFAOYSA-N 0.000 claims description 6
- 238000000034 method Methods 0.000 claims description 6
- 239000003795 chemical substances by application Substances 0.000 claims description 5
- 239000007798 antifreeze agent Substances 0.000 claims description 3
- DGVVJWXRCWCCOD-UHFFFAOYSA-N naphthalene;hydrate Chemical compound O.C1=CC=CC2=CC=CC=C21 DGVVJWXRCWCCOD-UHFFFAOYSA-N 0.000 claims description 3
- 239000004566 building material Substances 0.000 abstract description 3
- 239000000843 powder Substances 0.000 description 11
- 238000010276 construction Methods 0.000 description 8
- 229910000831 Steel Inorganic materials 0.000 description 6
- 239000010959 steel Substances 0.000 description 6
- 238000005336 cracking Methods 0.000 description 5
- 229910052500 inorganic mineral Inorganic materials 0.000 description 5
- 239000011707 mineral Substances 0.000 description 5
- 238000001816 cooling Methods 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 238000003756 stirring Methods 0.000 description 3
- 239000010754 BS 2869 Class F Substances 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 2
- 230000006835 compression Effects 0.000 description 2
- 238000007906 compression Methods 0.000 description 2
- 239000000498 cooling water Substances 0.000 description 2
- 238000012423 maintenance Methods 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- 238000005303 weighing Methods 0.000 description 2
- 230000001680 brushing effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000005457 optimization Methods 0.000 description 1
- 239000004482 other powder Substances 0.000 description 1
- 238000004806 packaging method and process Methods 0.000 description 1
- 238000011056 performance test Methods 0.000 description 1
- 238000004321 preservation Methods 0.000 description 1
- 230000002265 prevention Effects 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 230000003014 reinforcing effect Effects 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000010998 test method 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
- C04B28/02—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 containing hydraulic cements other than calcium sulfates
- C04B28/04—Portland cements
-
- 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
- C04B2111/00—Mortars, concrete or artificial stone or mixtures to prepare them, characterised by specific function, property or use
- C04B2111/20—Resistance against chemical, physical or biological attack
-
- 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
-
- 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
- C04B2201/52—High compression strength concretes, i.e. with a compression strength higher than about 55 N/mm2, e.g. reactive powder concrete [RPC]
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Ceramic Engineering (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Inorganic Chemistry (AREA)
- Materials Engineering (AREA)
- Structural Engineering (AREA)
- Organic Chemistry (AREA)
- Curing Cements, Concrete, And Artificial Stone (AREA)
Abstract
The invention belongs to the field of building materials, and particularly relates to mass concrete and a production method thereof. The invention aims to solve the technical problem of providing a mass concrete which comprises the following raw materials in parts by weight: 240-400 parts of ordinary portland cement, 80-160 parts of fly ash, 700-1000 parts of machine-made sand, 800-1200 parts of broken stone, 5-20 parts of an additive and 150-175 parts of clear water. The concrete obtained by the invention has higher early strength.
Description
Technical Field
The invention belongs to the field of building materials, and particularly relates to mass concrete and a production method thereof.
Background
In the field of building engineering, high-strength mass concrete is more and more widely applied, and the prevention of cracking is the primary problem to be faced by mass concrete. The measures for preventing cracking are mainly comprehensive application in various aspects such as concrete material selection and proportioning, concrete curing, construction method and the like.
The cost of mass concrete of the same grade is generally higher than that of ordinary concrete because of the higher requirements on raw materials and equipment for producing mass concrete.
In the aspects of concrete material selection and proportioning optimization, methods such as low-heat cement, double-doped fly ash, mineral powder and large-doped fly ash are mainly adopted, the principle is that the hydration heat is reduced or the hydration reaction is prolonged to reduce the peak value of the hydration heat, and meanwhile, necessary internal cooling measures and external heat preservation measures are assisted to prevent cracking caused by overlarge temperature difference between the interior and the surface of the concrete.
The low-heat cement has low hydration heat value, belongs to special cement, is usually much higher than common Portland cement in selling price, and has limited purchasing channel source. And in order to prevent different types of cement mixing, a common mixing plant needs to vacate a special line to produce mass concrete, so that the equipment utilization rate is reduced, and the production cost is further increased.
The adoption of the mode of double doping of mineral powder and fly ash is beneficial to reducing the cost of raw materials, but increases the construction cost. The cement, fly ash or mineral powder and other powder which are newly pumped into the powder tank body cannot be directly used due to overhigh temperature, and can be used for production after natural cooling. Therefore, at least two powder tanks are arranged for each type of powder on one production line of the concrete mixing plant. The addition of an admixture needs to increase the cost of infrastructure, tank and accessory equipment purchase, stirring main building packaging and the like for the added powder tank. And 4 powder tank bodies are arranged on one production line of a plurality of old mixing stations, and the double-mixing production condition is not met. In addition, the large-volume concrete produced by adopting the double-doped mineral powder and the fly ash has low early strength, long maintenance period and no adaptability to construction with fast pace, has higher requirements on infrastructure of the mixing plant, and is not beneficial to popularization and production of all mixing plants.
The large-volume concrete produced by adopting the large-volume fly ash has low early strength and long maintenance period, and cannot meet the construction requirement of fast pace.
Disclosure of Invention
Aiming at the defects of the mass concrete prepared by the existing method, the invention provides the mass concrete which comprises the following components in parts by weight: 240-400 parts of ordinary portland cement, 80-160 parts of fly ash, 700-1000 parts of machine-made sand, 800-1200 parts of broken stone, 5-20 parts of an additive and 150-175 parts of clear water; wherein the ordinary portland cement is P.O42.5R cement, the content of tricalcium aluminate in the cement is less than or equal to 7 percent, the heat of hydration in 3 days is less than or equal to 250kJ/kg, and the heat of hydration in 7 days is less than or equal to 300 kJ/kg.
In the mass concrete, the fly ash is class F I fly ash or class F II fly ash.
In the large-volume concrete, the broken stones are graded broken stones of 5-31 mm, and the mud content is less than or equal to 1%. Preferably 5-26.5 mm continuous graded broken stone.
In the mass concrete, the machine-made sand is high-quality medium sand with the fineness modulus of 2.4-3.0, and the mud content is less than or equal to 3%.
In the mass concrete, the additive is at least one of a polycarboxylic acid water reducing agent, a naphthalene water reducing agent, an antifreeze agent and an air entraining agent. Preferably a polycarboxylic acid water reducing agent.
The invention also provides a production method of the large-volume concrete. The production method comprises the following steps: mixing the raw materials uniformly, pouring into a mold, and curing at normal temperature to obtain the product.
The invention adopts the ordinary Portland cement with special properties and the mass concrete produced by adopting the mode of singly mixing the fly ash, has high early strength and is suitable for the engineering with higher construction speed requirement and needing early form removal. The cost of the bulk concrete raw material is consistent with that of the common concrete raw material with the same grade, and is lower than the production cost of the traditional common bulk concrete, and the equipment required by production is the same as that of the common concrete, so that the additional powder tank is not required. The large-volume concrete provided by the invention has a lower hydration heat peak value, can be cooled by cooling water without adopting a cooling pipeline arranged inside, and can be used for simply making temperature control measures in the curing period without cracking. The mass concrete of the invention has the advantages of no cracking, high early strength, rapid form removal, simple production control, low cost compared with the high-strength mass concrete prepared by low-heat cement, and wide application in mass structural parts such as bridges, tunnels, hydropower stations and the like.
Detailed Description
The invention relates to a mass concrete which comprises the following raw materials in parts by weight: 240-400 parts of ordinary portland cement, 80-160 parts of fly ash, 700-1000 parts of machine-made sand, 800-1200 parts of broken stone, 5-20 parts of an additive and 150-175 parts of clear water; wherein the ordinary portland cement is P.O42.5R cement, the content of tricalcium aluminate in the cement is less than or equal to 7 percent, the heat of hydration in 3 days is less than or equal to 250kJ/kg, and the heat of hydration in 7 days is less than or equal to 300 kJ/kg.
Further, the mass concrete of the invention comprises the following concrete components in each cubic meter: 240-400 kg of ordinary portland cement, 80-160 kg of fly ash, 700-1000 kg of machine-made sand, 800-1200 kg of broken stone, 5-20 kg of additive and 150-175 kg of clear water; wherein the ordinary portland cement is P.O42.5R cement, the content of tricalcium aluminate in the cement is less than or equal to 7 percent, the heat of hydration in 3 days is less than or equal to 250kJ/kg, and the heat of hydration in 7 days is less than or equal to 300 kJ/kg.
The raw material cement adopted by the invention needs to be early strength type ordinary portland cement with 42.5Mpa strength grade and P.O42.5R code, wherein the active mixed material is mineral powder, the tricalcium aluminate content in the cement is less than or equal to 7%, the 3-day hydration heat is less than or equal to 240kJ/kg, and the 7-day hydration heat is less than or equal to 280 kJ/kg. If the content of tricalcium aluminate in the cement is more than or equal to 8 percent, the cement is not suitable for being applied to the invention. The cement hydration heat is measured according to the measuring method of the cement hydration heat of GB/T12959-2008.
The fly ash is F class I fly ash or F class II fly ash.
The crushed stone is 5-31 mm graded crushed stone, and the mud content is less than or equal to 1%. Preferably 5-26.5 mm continuous graded broken stone.
The machine-made sand is high-quality medium sand with the fineness modulus of 2.4-3.0, and the mud content is less than or equal to 3%.
The additive is at least one of a polycarboxylic acid water reducing agent, a naphthalene water reducing agent, an antifreeze agent and an air entraining agent. Preferably a polycarboxylic acid water reducing agent.
In the present invention, the content is not particularly specified, and all the contents refer to mass%.
Example 1
The size of a bearing platform of a super bridge mainly has the following specifications: 2 20.5m 17m 4m, 4 10m 17m 4m, 16 5.2m 2m, 94 2.5m 6.25m 2.5m, etc., which belong to the construction of large-volume concrete.
The method comprises the steps of arranging a large assembled steel mould on a flat and solid cement ground, binding steel bars according to standard specifications, arranging cooling water pipes and temperature measuring holes side by side, brushing a release agent on the inner surface of the mould, and reinforcing and supporting the periphery by using flat steel and a groove cover.
Accurately weighing various components in parts by weight, wherein each cubic concrete comprises the following components in parts by weight: 300kg of ordinary portland cement (cement indexes: C3A 7%, three-day hydration heat 223kJ/kg, 7-day hydration heat 266kJ/kg), 80kg of fly ash, 1020kg of broken stone, 840kg of machine-made sand, 5.5kg of polycarboxylic acid high-performance water reducing agent and 165kg of clear water.
Mixing and stirring ordinary portland cement, fly ash, machine-made sand, broken stone, a polycarboxylic acid high-performance water reducing agent and clean water for 80 s; pouring into a mold in layers according to the height of 30cm, covering a film on the surface after pouring, keeping the temperature, removing the mold after 24h, and watering and curing.
Example 2
The sizes of the pier columns of the extra-large bridge are all larger, wherein the sizes of the middle piers and the side piers of the main bridges 46# and 47# are 14m × 12m × 17m, and the sizes of the bottom surfaces of the side piers are 14m × 7m × 17m, and the extra-large bridge belongs to large-volume concrete construction.
And arranging a large block assembled steel mould on the top surface of the bearing platform, and binding the steel bars according to standard specifications. The inner surface of the template is brushed with a release agent, and the periphery is reinforced and supported by flat steel and a groove cover.
Accurately weighing various components in parts by weight, wherein each cubic concrete comprises the following components in parts by weight: 340kg of ordinary portland cement (cement index: C3A 7%, three-day hydration heat 223kJ/kg, 7-day hydration heat 266kJ/kg), 80kg of fly ash, 990kg of gravel, 830kg of machine-made sand, 6.3kg of polycarboxylic acid high-performance water reducing agent and 165kg of water.
Mixing and stirring ordinary portland cement, fly ash, machine-made sand, broken stone, a polycarboxylic acid high-performance water reducing agent and clean water for 80 s; pouring into a mold in layers according to the height of 30cm, covering a film on the surface after pouring, keeping the temperature, removing the mold after 24h, and watering and curing.
The slump and the expansion are measured according to the GB/T50080-2016 common concrete mixture performance test method standard. The surface state was visually observed. The compressive strength is determined by adopting the GB/T50081-2019 common concrete mechanical property test method standard, and the result is evaluated by adopting the GB/T50107-2010 concrete strength test evaluation standard. The name of the compression strength detection instrument is as follows: DYE-3000 compression testing machine, manufacturer: Waitai-Sn-free building materials instruments ltd. The average value of the performance indexes of the bulk concrete obtained in example 1 is shown in table 1 below, and the average value of the performance indexes of the bulk concrete obtained in example 2 is shown in table 1 below.
TABLE 1 Mass concrete Properties
The results show that the mass concrete produced by preferentially selecting the ordinary portland cement with lower hydration heat and adopting the single-doped fly ash mode has high early strength and can be suitable for projects with higher construction speed requirements and requiring early form removal; the raw material cost and the equipment cost required by the production of the mass concrete are comprehensively low; the large-volume concrete provided by the invention has a low hydration heat peak value, and a temperature control measure in a curing period is simply made, so that the concrete does not crack.
Claims (6)
1. Bulky concrete, its characterized in that: the raw materials comprise the following components in parts by weight: 240-400 parts of ordinary portland cement, 80-160 parts of fly ash, 700-1000 parts of machine-made sand, 800-1200 parts of broken stone, 5-20 parts of an additive and 150-175 parts of clear water; wherein the ordinary portland cement is P.O42.5R cement, the content of tricalcium aluminate in the cement is less than or equal to 7 percent, the heat of hydration in 3 days is less than or equal to 250kJ/kg, and the heat of hydration in 7 days is less than or equal to 300 kJ/kg.
2. The bulk concrete according to claim 1, wherein: the fly ash is F class I fly ash or F class II fly ash.
3. The mass concrete according to claim 1 or 2, wherein: the crushed stone is 5-31 mm graded crushed stone, and the mud content is less than or equal to 1%; preferably 5-26.5 mm continuous graded broken stone.
4. A bulk concrete according to any one of claims 1 to 3, wherein: the machine-made sand is high-quality medium sand with the fineness modulus of 2.4-3.0, and the mud content is less than or equal to 3%.
5. A bulk concrete according to any one of claims 1 to 4, wherein: the additive is at least one of a polycarboxylic acid water reducing agent, a naphthalene water reducing agent, an antifreeze agent and an air entraining agent; preferably a polycarboxylic acid water reducing agent.
6. The method for producing mass concrete according to any one of claims 1 to 5, wherein: the method comprises the following steps: mixing the raw materials uniformly, pouring into a mold, and curing at normal temperature to obtain the product.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110350905.1A CN113149549A (en) | 2021-03-31 | 2021-03-31 | Mass concrete and production method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110350905.1A CN113149549A (en) | 2021-03-31 | 2021-03-31 | Mass concrete and production method thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN113149549A true CN113149549A (en) | 2021-07-23 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110350905.1A Pending CN113149549A (en) | 2021-03-31 | 2021-03-31 | Mass concrete and production method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113149549A (en) |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2013052952A2 (en) * | 2011-10-06 | 2013-04-11 | Cement Innovations, Llc | Cement additives and related methods of use |
| CN105948619A (en) * | 2016-04-28 | 2016-09-21 | 十九冶成都建设有限公司 | Anti-crack mass concrete prepared by utilizing fly ash and mineral powder double-mixing technology |
| CN107445552A (en) * | 2017-08-28 | 2017-12-08 | 北京铁建永泰新型建材有限公司 | Cracking resistance enhancing large volume super-long structural concrete and preparation method thereof |
| CN109369097A (en) * | 2018-11-08 | 2019-02-22 | 中国核工业华兴建设有限公司 | A kind of low cracking resistance mass concrete of high performance of creeping of lower shrinkage |
-
2021
- 2021-03-31 CN CN202110350905.1A patent/CN113149549A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2013052952A2 (en) * | 2011-10-06 | 2013-04-11 | Cement Innovations, Llc | Cement additives and related methods of use |
| CN105948619A (en) * | 2016-04-28 | 2016-09-21 | 十九冶成都建设有限公司 | Anti-crack mass concrete prepared by utilizing fly ash and mineral powder double-mixing technology |
| CN107445552A (en) * | 2017-08-28 | 2017-12-08 | 北京铁建永泰新型建材有限公司 | Cracking resistance enhancing large volume super-long structural concrete and preparation method thereof |
| CN109369097A (en) * | 2018-11-08 | 2019-02-22 | 中国核工业华兴建设有限公司 | A kind of low cracking resistance mass concrete of high performance of creeping of lower shrinkage |
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Application publication date: 20210723 |