CN116477890A - Ultra-high performance concrete and preparation method thereof - Google Patents
Ultra-high performance concrete and preparation method thereof Download PDFInfo
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- CN116477890A CN116477890A CN202210050462.9A CN202210050462A CN116477890A CN 116477890 A CN116477890 A CN 116477890A CN 202210050462 A CN202210050462 A CN 202210050462A CN 116477890 A CN116477890 A CN 116477890A
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- quartz sand
- ultra
- high performance
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- 239000011374 ultra-high-performance concrete Substances 0.000 title claims abstract description 46
- 238000002360 preparation method Methods 0.000 title claims abstract description 16
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 45
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims abstract description 44
- 239000006004 Quartz sand Substances 0.000 claims abstract description 42
- 239000004568 cement Substances 0.000 claims abstract description 26
- 239000003638 chemical reducing agent Substances 0.000 claims abstract description 23
- 229910021487 silica fume Inorganic materials 0.000 claims abstract description 19
- 229910000831 Steel Inorganic materials 0.000 claims abstract description 16
- 239000000835 fiber Substances 0.000 claims abstract description 16
- 239000010959 steel Substances 0.000 claims abstract description 16
- 238000003756 stirring Methods 0.000 claims description 27
- 239000011325 microbead Substances 0.000 claims description 13
- 239000002245 particle Substances 0.000 claims description 9
- 239000004570 mortar (masonry) Substances 0.000 claims description 5
- 239000010881 fly ash Substances 0.000 claims description 4
- 239000007787 solid Substances 0.000 claims description 3
- 238000005303 weighing Methods 0.000 claims description 3
- 229920005646 polycarboxylate Polymers 0.000 claims 2
- 239000008030 superplasticizer Substances 0.000 claims 2
- 239000011398 Portland cement Substances 0.000 claims 1
- 238000004519 manufacturing process Methods 0.000 abstract description 7
- 239000004567 concrete Substances 0.000 description 7
- 239000002253 acid Substances 0.000 description 4
- 238000005056 compaction Methods 0.000 description 4
- 238000000034 method Methods 0.000 description 4
- 230000009286 beneficial effect Effects 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 239000004576 sand Substances 0.000 description 2
- 238000007790 scraping Methods 0.000 description 2
- 239000003469 silicate cement Substances 0.000 description 2
- 238000009435 building construction Methods 0.000 description 1
- 239000011083 cement mortar Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000007676 flexural strength test Methods 0.000 description 1
- 230000036571 hydration Effects 0.000 description 1
- 238000006703 hydration reaction 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
- 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
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W30/00—Technologies for solid waste management
- Y02W30/50—Reuse, recycling or recovery technologies
- Y02W30/91—Use of waste materials as fillers for mortars or concrete
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 discloses ultra-high performance concrete and a preparation method thereof, comprising the following steps: 690-850 parts by mass of cement, 200 parts by mass of silica fume, 226-348 parts by mass of 40-70 mesh quartz sand, 464-556 parts by mass of 26-40 mesh quartz sand, 340-348 parts by mass of 16-26 mesh quartz sand, 158-200 parts by mass of steel fiber, 22.22-34.65 parts by mass of water reducer and 168-182 parts by mass of water. The invention solves the problems of high production cost and complex production process of the ultra-high performance concrete.
Description
Technical Field
The invention relates to the technical field of building construction, in particular to ultra-high performance concrete and a preparation method thereof.
Background
Ultra-high performance concrete (UHPC for short) is a novel cement-based material with high strength, high toughness and high durability. Compared with the traditional concrete, the UHPC has the characteristics of high compressive strength, good toughness, reliable structure, high durability, excellent wear resistance and the like, and the structural dead weight is about 1/3 or 1/2 of that of the traditional concrete structure, so that the dead load is obviously reduced, the UHPC is beneficial to manufacturing a more slender building structure, and the materials and the cost are saved. Based on the advantages, the ultra-high performance concrete has important significance in engineering applications such as bridges, subways, dams, stairways, balconies and the like.
However, UHPC also has some drawbacks such as excessively high hydration heat, large volume shrinkage, high production cost, complicated production process, large viscosity, large slump loss, and the like.
Disclosure of Invention
In order to overcome the defects existing in the prior art, the ultra-high performance concrete and the preparation method thereof are provided, so that the problems of high production cost and complex production process of the ultra-high performance concrete are solved.
To achieve the above object, there is provided an ultra-high performance concrete comprising:
comprising the following steps: 690-850 parts by mass of cement, 200 parts by mass of silica fume, 226-348 parts by mass of 40-70 mesh quartz sand, 464-556 parts by mass of 26-40 mesh quartz sand, 340-348 parts by mass of 16-26 mesh quartz sand, 158-200 parts by mass of steel fiber, 22.22-34.65 parts by mass of water reducer and 168-182 parts by mass of water.
Further, the method comprises the steps of: 850 parts by mass of cement, 200 parts by mass of silica fume, 226 parts by mass of 40-70 mesh quartz sand, 556 parts by mass of 26-40 mesh quartz sand, 340 parts by mass of 16-26 mesh quartz sand, 168 parts by mass of water, 200 parts by mass of steel fiber and 34.65 parts by mass of water reducer.
Further, the method comprises the steps of: 690 parts by mass of cement, 200 parts by mass of silica fume, 120 parts by mass of microbeads, 348 parts by mass of 40-70 mesh quartz sand, 464 parts by mass of 26-40 mesh quartz sand, 348 parts by mass of 16-26 mesh quartz sand, 158 parts by mass of steel fiber, 22.22 parts by mass of water reducer and 182 parts by mass of water.
Further, the water reducer is a polycarboxylic acid high-efficiency water reducer.
Further, the water reducing rate of the polycarboxylic acid high-efficiency water reducing agent is 34%, and the solid content is 24.2%.
Further, the cement is P.II 52.5 silicate cement, the compressive strength of the 28d mortar of the cement is not lower than 58.2MPa, and the water consumption of the standard consistency of the cement is less than 29.6wt%.
Further, siO in the silica fume 2 The content is 92% or more, siO 2 The particle size of the particles is 325 to 1250 meshes.
Further, the microbeads are fly ash microbeads, and the particle size of the fly ash microbeads is 380 mu m.
The invention provides a preparation method of ultra-high performance concrete, which comprises the following steps:
respectively weighing 690-850 parts by mass of cement, 200 parts by mass of silica fume, 226-348 parts by mass of 40-70 mesh quartz sand, 464-556 parts by mass of 26-40 mesh quartz sand, 340-348 parts by mass of 16-26 mesh quartz sand, 158-200 parts by mass of steel fiber, 22.22-34.65 parts by mass of water reducer and 168-182 parts by mass of water;
adding water and a water reducing agent into a stirrer;
adding cement, silica fume and microbeads, and stirring at a low speed for a stirring period of 30s;
adding quartz sand and steel fibers at the beginning of the second stirring period, and stopping stirring for 90 seconds;
and after stopping the stirring for 90 seconds, stirring at a high speed for two stirring periods to obtain the ultra-high performance concrete.
The invention has the beneficial effects that the ultra-high performance concrete can be produced by adopting a common process. The components and the proportion of the ultra-high performance concrete of the invention ensure the strength requirement of UHPC, improve the workability of the concrete and improve the flexural strength.
Detailed Description
The present application is described in further detail below with reference to examples. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting of the invention.
It should be noted that, in the case of no conflict, the embodiments and features in the embodiments may be combined with each other. The present application will be described in detail with reference to examples.
The invention provides ultra-high performance concrete, comprising: 690-850 parts by mass of cement, 200 parts by mass of silica fume, 226-348 parts by mass of 40-70 mesh quartz sand, 464-556 parts by mass of 26-40 mesh quartz sand, 340-348 parts by mass of 16-26 mesh quartz sand, 158-200 parts by mass of steel fiber, 22.22-34.65 parts by mass of water reducer and 168-182 parts by mass of water.
As a preferred embodiment, the water reducing agent is a polycarboxylic acid high efficiency water reducing agent.
In this example, the polycarboxylic acid high-efficiency water reducing agent had a water reducing rate of 34% and a solid content of 24.2%.
As a preferred embodiment, the cement is P.II 52.5 silicate cement, the compressive strength of the 28d mortar of the cement is not lower than 58.2MPa, and the water consumption of the standard consistency of the cement is less than 29.6wt%.
As a preferred embodiment, siO in the silica fume 2 The content is 92% or more, siO 2 The particle size of the particles is 325 to 1250 meshes.
As a preferred embodiment, the microbeads are fly ash microbeads having a particle size of 380 μm.
The invention provides a preparation method of ultra-high performance concrete, which comprises the following steps:
s1: respectively weighing 690-850 parts by mass of cement, 200 parts by mass of silica fume, 226-348 parts by mass of 40-70 mesh quartz sand, 464-556 parts by mass of 26-40 mesh quartz sand, 340-348 parts by mass of 16-26 mesh quartz sand, 158-200 parts by mass of steel fiber, 22.22-34.65 parts by mass of water reducer and 168-182 parts by mass of water.
S2: the water and the water reducing agent are added into a stirrer. The mixer is a JJ-5 cement mortar mixer.
S3: cement, silica fume and microbeads were added and stirred at low speed for a stirring period of 30s.
S4: at the beginning of the second stirring cycle, quartz sand and steel fibers were added, after which stirring was stopped for 90s.
In the preparation of the ultra-high performance concrete of the present invention, stirring was carried out at a low speed for 2 stirring cycles of 30s each.
In the invention, the rotating speed of the low-speed stirring of the stirrer is 140+/-5 revolutions per minute; the stirring speed of the stirrer at high speed was 285.+ -.10 rpm.
S5: and after stopping the stirring for 90 seconds, stirring at a high speed for two stirring periods to obtain the ultra-high performance concrete.
In the preparation of the ultra-high performance concrete of the present invention, after stopping stirring for 90 seconds, stirring was further performed at a high speed for 2 stirring cycles of 30 seconds each.
Example 1
The invention provides ultra-high performance concrete, comprising: 850 parts by mass of cement, 200 parts by mass of silica fume, 226 parts by mass of 40-70 mesh quartz sand, 556 parts by mass of 26-40 mesh quartz sand, 340 parts by mass of 16-26 mesh quartz sand, 168 parts by mass of water, 200 parts by mass of steel fiber and 34.65 parts by mass of water reducer.
The preparation of the ultra-high performance concrete is carried out by adopting the preparation method of the ultra-high performance concrete.
After the preparation of the ultra-high performance concrete of the invention, the mixed concrete mortar is poured into a triple mold with the thickness of 40mm multiplied by 160mm twice and is put on a vibrating table for compaction, and the compaction is carried out under 60 times each time. And (5) scraping redundant rubber sand in the die, and trowelling the surface. And (3) after curing for 24 hours in a fog room, demolding, curing in a curing box, and performing related mechanical property test after curing to a specified age.
Example two
The invention provides ultra-high performance concrete, comprising: 690 parts by mass of cement, 200 parts by mass of silica fume, 120 parts by mass of microbeads, 348 parts by mass of 40-70 mesh quartz sand, 464 parts by mass of 26-40 mesh quartz sand, 348 parts by mass of 16-26 mesh quartz sand, 158 parts by mass of steel fiber, 22.22 parts by mass of water reducer and 182 parts by mass of water.
The preparation of the ultra-high performance concrete is carried out by adopting the preparation method of the ultra-high performance concrete.
After the preparation of the ultra-high performance concrete of the invention, the mixed concrete mortar is poured into a triple mold with the thickness of 40mm multiplied by 160mm twice and is put on a vibrating table for compaction, and the compaction is carried out under 60 times each time. And (5) scraping redundant rubber sand in the die, and trowelling the surface. And (3) after curing for 24 hours in a fog room, demolding, curing in a curing box, and performing related mechanical property test after curing to a specified age.
The concrete test blocks prepared in the first and second examples were subjected to compressive strength and flexural strength tests for 3 days, 7 days and 28 days by using a WYA-300B full-automatic flexural and compressive tester, and the obtained ultra-high performance concrete test blocks were subjected to the performance data results shown in Table 1 below.
TABLE 1 compressive and flexural Strength of test pieces 3d, 7d and 28d
The ultra-high performance concrete can be produced by adopting a common process. The components and the proportion of the ultra-high performance concrete of the invention ensure the strength requirement of UHPC, improve the workability of the concrete and improve the flexural strength.
The foregoing description is only of the preferred embodiments of the present application and is presented as a description of the principles of the technology being utilized. It will be appreciated by persons skilled in the art that the scope of the invention referred to in this application is not limited to the specific combinations of features described above, but it is intended to cover other embodiments in which any combination of features described above or equivalents thereof is possible without departing from the spirit of the invention. Such as the above-described features and technical features having similar functions (but not limited to) disclosed in the present application are replaced with each other.
Claims (9)
1. An ultra-high performance concrete comprising: 690-850 parts by mass of cement, 200 parts by mass of silica fume, 226-348 parts by mass of 40-70 mesh quartz sand, 464-556 parts by mass of 26-40 mesh quartz sand, 340-348 parts by mass of 16-26 mesh quartz sand, 158-200 parts by mass of steel fiber, 22.22-34.65 parts by mass of water reducer and 168-182 parts by mass of water.
2. The ultra-high performance concrete of claim 1, comprising: 850 parts by mass of cement, 200 parts by mass of silica fume, 226 parts by mass of 40-70 mesh quartz sand, 556 parts by mass of 26-40 mesh quartz sand, 340 parts by mass of 16-26 mesh quartz sand, 168 parts by mass of water, 200 parts by mass of steel fiber and 34.65 parts by mass of water reducer.
3. The ultra-high performance concrete of claim 1, comprising: 690 parts by mass of cement, 200 parts by mass of silica fume, 120 parts by mass of microbeads, 348 parts by mass of 40-70 mesh quartz sand, 464 parts by mass of 26-40 mesh quartz sand, 348 parts by mass of 16-26 mesh quartz sand, 158 parts by mass of steel fiber, 22.22 parts by mass of water reducer and 182 parts by mass of water.
4. The ultra-high performance concrete of claim 1, wherein the water reducer is a polycarboxylate superplasticizer.
5. The ultra-high performance concrete of claim 4, wherein the polycarboxylate superplasticizer has a water reduction rate of 34% and a solids content of 24.2%.
6. The ultra-high performance concrete of claim 1, wherein the cement is p.ii 52.5 portland cement, the 28d mortar compressive strength of the cement is not less than 58.2MPa, and the water usage of the standard consistency of the cement is less than 29.6wt%.
7. The ultra-high performance concrete of claim 1, wherein the SiO in the silica fume 2 The content is 92% or more, siO 2 The particle size of the particles is 325 to 1250 meshes.
8. The ultra-high performance concrete of claim 1, wherein the microbeads are fly ash microbeads having a particle size of 380 μm.
9. The preparation method of the ultra-high performance concrete is characterized by comprising the following steps of:
respectively weighing 690-850 parts by mass of cement, 200 parts by mass of silica fume, 226-348 parts by mass of 40-70 mesh quartz sand, 464-556 parts by mass of 26-40 mesh quartz sand, 340-348 parts by mass of 16-26 mesh quartz sand, 158-200 parts by mass of steel fiber, 22.22-34.65 parts by mass of water reducer and 168-182 parts by mass of water;
adding water and a water reducing agent into a stirrer;
adding cement, silica fume and microbeads, and stirring at a low speed for a stirring period of 30s;
adding quartz sand and steel fibers at the beginning of the second stirring period, and stopping stirring for 90 seconds;
and after stopping the stirring for 90 seconds, stirring at a high speed for two stirring periods to obtain the ultra-high performance concrete.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210050462.9A CN116477890A (en) | 2022-01-17 | 2022-01-17 | Ultra-high performance concrete and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210050462.9A CN116477890A (en) | 2022-01-17 | 2022-01-17 | Ultra-high performance concrete and preparation method thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN116477890A true CN116477890A (en) | 2023-07-25 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210050462.9A Pending CN116477890A (en) | 2022-01-17 | 2022-01-17 | Ultra-high performance concrete and preparation method thereof |
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103274652A (en) * | 2013-06-20 | 2013-09-04 | 中建三局建设工程股份有限公司 | Reactive powder concrete for reinforcing buildings as well as preparation method and construction method thereof |
| KR20160144058A (en) * | 2015-06-08 | 2016-12-16 | 한국건설기술연구원 | Ultra-high performance concrete for mixing micro basalt fiber and macro steel fiber, and manufacturing method for the same |
| CN107265983A (en) * | 2017-08-08 | 2017-10-20 | 天津城建大学 | A kind of 180MPa ultra-high performance concretes and preparation method thereof |
| CN112456920A (en) * | 2020-12-18 | 2021-03-09 | 成都宏基建材股份有限公司 | High flow state ultra-high performance concrete |
| CN112456902A (en) * | 2020-11-27 | 2021-03-09 | 苏州三佳交通工程有限公司 | Ultrahigh-performance concrete and preparation method thereof |
-
2022
- 2022-01-17 CN CN202210050462.9A patent/CN116477890A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103274652A (en) * | 2013-06-20 | 2013-09-04 | 中建三局建设工程股份有限公司 | Reactive powder concrete for reinforcing buildings as well as preparation method and construction method thereof |
| KR20160144058A (en) * | 2015-06-08 | 2016-12-16 | 한국건설기술연구원 | Ultra-high performance concrete for mixing micro basalt fiber and macro steel fiber, and manufacturing method for the same |
| CN107265983A (en) * | 2017-08-08 | 2017-10-20 | 天津城建大学 | A kind of 180MPa ultra-high performance concretes and preparation method thereof |
| CN112456902A (en) * | 2020-11-27 | 2021-03-09 | 苏州三佳交通工程有限公司 | Ultrahigh-performance concrete and preparation method thereof |
| CN112456920A (en) * | 2020-12-18 | 2021-03-09 | 成都宏基建材股份有限公司 | High flow state ultra-high performance concrete |
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