CN111792857A - Composite ultrafine powder for ultrahigh-strength concrete, ultrahigh-strength concrete and preparation method thereof - Google Patents
Composite ultrafine powder for ultrahigh-strength concrete, ultrahigh-strength concrete and preparation method thereof Download PDFInfo
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
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- C04B7/00—Hydraulic cements
- C04B7/24—Cements from oil shales, residues or waste other than slag
- C04B7/26—Cements from oil shales, residues or waste other than slag from raw materials containing flue dust, i.e. fly ash
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- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
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- 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
- C04B28/08—Slag cements
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- C04B40/00—Processes, in general, for influencing or modifying the properties of mortars, concrete or artificial stone compositions, e.g. their setting or hardening ability
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- C04B40/0039—Premixtures of ingredients
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- 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
- C04B2111/00017—Aspects relating to the protection of the environment
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- 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
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- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P40/00—Technologies relating to the processing of minerals
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- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
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Abstract
The invention relates to the technical field of building materials, in particular to composite ultrafine powder for ultrahigh-strength concrete, ultrahigh-strength high-performance concrete and a preparation method thereof, wherein the use amounts of fly ash microbeads, mineral powder and silica fume are controlled, so that the proportioning is reasonable, the microcosmic continuous grading of each powder material is realized, and the micro-aggregate effect of the powder material is exerted, so that after the concrete is added, the compactness of the concrete is improved, the strength and durability of the concrete are enhanced, the viscosity of a concrete mixture is reduced, the workability is improved, the use amount of the cement is reduced, and the production cost is reduced; the composite ultrafine powder prepared under a proper mixing proportion is added into concrete preparation, so that the compressive strength of the concrete can reach more than 120 MPa.
Description
Technical Field
The invention relates to the technical field of building materials, in particular to composite ultrafine powder for ultrahigh-strength concrete, ultrahigh-strength concrete and a preparation method thereof.
Background
With the continuous progress of building technology and special requirements of building structures in China, various super high-rise buildings and large-span structures are greatly increased, higher requirements are put forward on concrete, the traditional concrete technology cannot meet the requirement of the engineering construction which is changing day by day, and the development of super high-strength high-performance concrete is urgently needed. The process of improving the strength of the concrete is the process of continuously reducing the internal defects of the concrete and continuously improving the compactness. The ultrahigh-strength high-performance concrete not only has ultrahigh strength, but also has the advantages of high compactness, strong deformation resistance, low porosity and the like, so that the ultrahigh-strength high-performance concrete has excellent durability and even ultrahigh durability. The ultrahigh-strength high-performance concrete has excellent performance in the processes of impermeability test, chloride ion penetration resistance test, sulfate corrosion resistance test, frost resistance test and carbonization resistance test. The strength of the ultra-high strength concrete is generally defined between 100-140MPa, such as the concrete classification viewpoint proposed in the book "ultra-high strength and high performance concrete" by the professor of Puxincheng Chengcheng university.
The ultra-high-strength concrete requires lower water-cement ratio, large cement consumption and large cement hydration heat, so that the problems of slump loss blocks, shrinkage cracks and the like are easily caused, and the performances such as durability and the like of the ultra-high-strength concrete are poor; based on this, in order to improve the technical defect in the prior art, in the process of preparing the ultra-high-strength concrete raw material, the admixture and/or the additive is added to replace part of cement, so that the cement dosage is greatly reduced on the premise of enhancing the concrete strength and not reducing the comprehensive performance, thereby solving the problems of large hydration heat release, large shrinkage, quick slump loss and the like caused by excessive cement dosage.
For example: a CTF concrete synergist for Yangyang and Yangqing leather is used in high-strength concrete, and its test research [ J ]. practical technique 2016(2):134-137 describes the selection of four factors of water-cement ratio, flyash mixing amount, mineral powder mixing amount and sand rate to prepare concrete, and determines the concrete slump, compressive strength and other performances, and analyzes the improvement of high-strength concrete performance by the composite mixing of flyash and mineral powder, and analyzes the difference of admixture ratio and its influence on the performance of ultrahigh-strength concrete.
Study on properties of high-strength pump concrete prepared from low-water-cement-ratio fly ash composite mineral powder [ J ]. report on water resource and water engineering 2014 (4): 156-160 describes the performance influence test of the fly ash composite mineral powder on the high-performance concrete under the water-cement ratio of 0.20, and the following results are obtained: the fly ash concrete has low early strength and high later strength, the early strength of the slag micro-powder concrete develops rapidly, the complementation of the two on the concrete strength is obvious, the fly ash and the mineral powder are compounded according to the proportion of 1:1, the mixing ratio is 30 percent or 40 percent, the water-cement ratio is 0.20, the compressive strength is better, and the compressive strength reaches 91.5MPa in 90 days.
Wangming, etc. the influence of mineral powder and fly ash on the compressive strength of ultra-high-strength concrete [ J ] northern construction, 2017(4):57-61, it introduces the double blending of mineral powder or fly ash with water-cement ratio of 0.21, 10%, 20%, 30%, 40%, 50% and silica fume of 10% and the blending of the three, which shows that the effect is best when the three are blended, and the compressive strength of 56d reaches 110.5 MPa.
Weifengting, and the like, research on compression strength of different mineral admixture ultrahigh-strength concrete [ J ] low-temperature building technology, 2018 (1): in the text 28-31, the tests of mineral powder and fly ash with different mixing amounts and 10% silica fume double-mixing or complex-mixing are respectively adopted, and the test process is as follows: the water-gel ratio is controlled to be 0.21, 0.24 and 0.27, and the water-gel ratio is 0.24, 20% of mineral powder, 20% of fly ash and 10% of silica fume are mixed, so that the influence on the compressive strength of the concrete is the largest; under the same water-gel ratio, when the mixing amount of the silica fume is fixed, the mixing amount of the mineral powder and the fly ash is less than 40 percent, and after the mineral powder and the silica fume with the same mixing amount are mixed together, the influence degree of the early strength is greater than the double mixing of the fly ash and the silica fume and the compound mixing of the fly ash and the silica fume; along with the increase of the maintenance time, the increase speed of the compressive strength of 28d and 56d of different mineral powder and fly ash is gradually reduced, the influence difference of the early strength is gradually reduced, and the increase amplitude of the fly ash in the later period is higher than that of the mineral powder; when the mixing amount reaches 50%, the early strength is low, and when the mixing amount reaches 56d, the increase amplitude of the fly ash is slightly larger than that of the mineral powder; under the same water-gel ratio, the early strength shows the trend of increasing first and then alkali along with the increase of the doping amount of the mineral admixture, the development speed is higher than that of the middle and later stages, and the strength reaches about 70-80% at 28 d; when the water-to-gel ratio is 0.21, 0.24 and 0.27 respectively, the mineral powder and the fly ash with different doping amounts are respectively double-doped with 10% of silica fume or the mixture of the mineral powder and the fly ash, and the strength of the concrete is firstly increased and then reduced along with the continuous increase of the contents of the mineral powder and the fly ash.
In summary, after a large amount of single doping, double doping or complex doping of fly ash, mineral powder, silica fume and the like to prepare concrete is carried out in the prior art, the compressive strength and other comprehensive properties of the concrete are measured, and the influence of different doping materials on the change rule of the concrete performance is obtained; moreover, the composite ratio of the fly ash, the mineral powder and the silica fume is also researched, and the conclusion that the strength performance of the concrete is improved by the composite doping of the fly ash, the mineral powder and the silica fume is obtained, however, the compressive strength of the concrete obtained by the composite doping in the prior art is still low and is maintained within 130MPa, and the high-strength development of the concrete is greatly influenced; the reason for this is that: when the raw materials are compounded and blended, the mixture ratio of the raw material components is improper, so that the comprehensive performance of the concrete is improved poorly after the obtained compound blend is blended.
Disclosure of Invention
In order to solve the technical problems in the prior art, the invention provides composite ultrafine powder for ultrahigh-strength concrete, ultrahigh-strength concrete and a preparation method thereof.
The method is realized by the following technical scheme:
the invention aims to provide composite ultrafine powder for ultra-high strength concrete, which comprises the following raw materials, by weight, 50-60 parts of fly ash microbeads, 25-30 parts of mineral powder and 15-20 parts of silica fume. Through controlling the amount of the raw material components, the proportioning is reasonable, the microcosmic continuous grading of each powder material is realized, the micro aggregate effect of the powder material is exerted, the compactness of the concrete is improved after the concrete is added, the strength and the durability of the concrete are enhanced, the viscosity of a concrete mixture is reduced, the workability is improved, the cement amount is reduced, and the production cost is reduced.
The quality of the fly ash micro-beads adopted by the invention meets the I-grade ash requirement of GB/T1596 fly ash for cement and concrete; the quality of the mineral powder meets the requirement of S105 level mineral powder of GB/T18046 granulated blast furnace slag powder used in cement and concrete; the quality of the silica fume meets the requirements of GB/T27690 silica fume for mortar and concrete.
Preferably, the raw material components comprise 55 parts of fly ash microbeads, 25 parts of mineral powder and 20 parts of silica fume by weight. The composite superfine powder prepared under the mixing proportion is added into concrete preparation, so that the compressive strength of the concrete can reach 149.5 MPa.
The invention creates the compound ultra-fine powder for the ultra-high strength concrete, which comprises the following steps in the application process: mixing and stirring the fly ash micro-beads, the mineral powder and the silica fume uniformly to obtain composite superfine powder for the ultra-high strength concrete; preparing the composite ultrafine powder for the ultrahigh-strength concrete and cement into a cementing material; the composite ultrafine powder for the ultra-high strength concrete accounts for 30-40% of the total mass of the cementing material; and mixing and stirring the cementing material, machine-made sand, water and a surfactant uniformly. Pouring, vibrating and naturally curing the uniformly stirred materials for 28 days to obtain the ultrahigh-strength high-performance concrete, wherein the strength of the concrete reaches 120-149.6MPa, and the electric flux is less than or equal to 800 cc; the adopted cement is ordinary portland cement, and the quality of the cement meets the requirement of 52.5-grade ordinary portland cement of GB175 general portland cement; the quality of the surfactant meets the standard requirements of JG/T223 polycarboxylic acid high-performance water reducing agent, namely the polycarboxylic acid high-performance water reducing agent is adopted as the surfactant.
The invention also aims to provide a cementing material for ultra-high strength concrete, which is formed by compounding the composite ultrafine powder for ultra-high strength concrete and cement, wherein the composite ultrafine powder for ultra-high strength concrete accounts for 30-40% of the total mass of the cementing material; the cement is 52.5-grade ordinary portland cement. The cement consumption is fully replaced, the cement consumption is reduced by 30-40%, the generation of cement hydration heat is greatly reduced, the shrinkage is reduced, the cost is reduced, and the strength of the concrete can reach more than 128MPa after the concrete is added into the concrete and naturally cured for 28 days, and the electric flux is less than or equal to 800 cc.
Preferably, the composite ultrafine powder for the ultra-high strength concrete accounts for 35% of the total mass of the cementing material. Under the addition, the dosage of the cement is reduced, the cement cost is reduced, the defects caused by cement hydration heat are weakened, the strength of the concrete after natural curing for 28d reaches 132MPa, and meanwhile, the electric flux is less than or equal to 750 cc.
The invention also aims to provide the ultrahigh-strength high-performance concrete which consists of a cementing material, machine-made broken stones, water and a surfactant, wherein the dosage of the cementing material is 700-800kg/m3The sand rate is 30-32%, and the assumed volume weight of the ultrahigh-strength high-performance concrete is 2500-2600 kg/m3Designing, wherein the dosage of the surfactant accounts for 1.2-1.5% of the mass of the cementing material, and the water-gel ratio is 0.17-0.18; the cementing material is formed by compounding the composite ultrafine powder for the ultrahigh-strength concrete and cement, wherein the composite ultrafine powder for the ultrahigh-strength concrete accounts for 30-40% of the total mass of the cementing material; the cement is 52.5-grade ordinary portland cement. After natural curing for 28 days, the compressive strength reaches 128-149.6MPa, and the electric flux is less than or equal to 800 cc. The machine-made broken stone is formed by compounding 70-80% of broken stone and 20-30% of rice stone in percentage by mass; wherein: the granularity of the broken stone is 10-25mm, and the granularity of the rice stone is 5-10 mm. The quality of the crushed stone meets the I-type standard requirements of GB/T14685-2011 construction pebbles and crushed stones, and the maximum grain diameter is less than or equal to 25 mm; the quality of the sand meets the requirement of the I-type mechanism sand quality of the GB/T14684-2011 construction sand standard.
The invention also aims to provide a preparation method of the ultrahigh-strength high-performance concrete, which comprises the following steps:
(1) preparing composite superfine powder: mixing and stirring the fly ash micro-beads, the mineral powder and the silica fume uniformly;
(2) preparing a cementing material: the composite ultrafine powder is compounded with cement;
(3) preparing concrete: mixing the machine-made macadam, the cementing material, the surfactant and the water, uniformly stirring, pouring, vibrating and naturally curing to obtain the concrete.
When the composite ultrafine powder obtained by the invention is added into concrete for application, the water-cement ratio during concrete preparation is preferably less than or equal to 0.18. The water-cement ratio is not suitable to be too high, otherwise, the strength of the concrete is greatly influenced, and the strength of the concrete is lower than 120 MPa. Meanwhile, the addition amount of the raw materials in the composite ultrafine powder is reasonably controlled, and through experimental study, when the consumption of the silica fume is constant, the strength of the concrete during natural curing for 28 days is low due to the overhigh consumption of the fly ash, the strength is enhanced more than 40 days when the natural curing is required, and the composite ultrafine powder has obvious later-stage reinforcement; when the using amount of the fly ash is too low, the early strength of the concrete is better, but the electric flux is higher and reaches more than 1000cc, and the durability of the concrete is poorer.
Compared with the prior art, the invention has the technical effects that:
the use amounts of the fly ash microbeads, the mineral powder and the silica fume are controlled, so that the proportioning is reasonable, the microcosmic continuous gradation of each powder material is realized, the micro aggregate effect of the powder material is exerted, the compactness of the concrete is improved after the concrete is added, the strength and the durability of the concrete are enhanced, the viscosity of a concrete mixture is reduced, the workability is improved, the use amount of the cement is reduced, and the production cost is reduced; the composite ultrafine powder prepared under a proper mixing proportion is added into concrete preparation, so that the compressive strength of the concrete can reach more than 120 MPa.
In the using process, the ultrafine composite fine powder and cement are adopted to prepare the cementing material, the addition amount of the ultrafine composite fine powder accounts for 30-40% of the total mass of the cementing material, the use amount of the cement is greatly replaced, the use amount of the cement is reduced, the cost is reduced, and the cement hydration heat generation and the concrete cracking risk are weakened.
When the superfine composite fine powder created by the invention is used for preparing concrete, the water-cement ratio is properly controlled to be 0.17-0.18, and the preparation with the too high water-cement ratio is not suitable, otherwise, the comprehensive performance of the prepared concrete is influenced.
The fly ash micro-beads adopted in the invention are purchased in the market and extracted according to the prior art.
Drawings
FIG. 1 is a graph showing the relationship between compressive strength and curing cycle of concrete with added composite ultrafine powder.
FIG. 2 is a graph showing the relationship between compressive strength and water-cement ratio of concrete with the added composite superfine powder.
Detailed Description
The technical solution of the present invention is further defined below with reference to the specific embodiments, but the scope of the claims is not limited to the description.
Test 1: research on influence of composite ultrafine powder mixing materials with different mixing ratios on concrete performance
Preparation of concrete samples: mixing and stirring the cementing material, machine-made macadam, water and surfactant uniformly, pouring, vibrating and naturally curing for 28 days to obtain a concrete sample; wherein the dosage of the cementing material is 700kg/m3The sand rate is 30 percent, and the assumed volume weight of the concrete is 2500kg/m3Designing, wherein the dosage of the surfactant accounts for 1.2 percent of the mass of the cementing material, and the water-gel ratio is 0.17; the machine-made broken stone is formed by compounding 70% of broken stone and 30% of rice stone in percentage by mass, the granularity of the broken stone is 10-25mm, and the granularity of the rice stone is 5-10 mm; the adopted surfactant is a polycarboxylic acid high-performance water reducing agent (such as Kojie Point-SS polycarboxylic acid high-performance water reducing agent); the cementing material is formed by uniformly mixing and stirring composite ultrafine powder for the ultrahigh-strength concrete and 52.5-grade ordinary portland cement, wherein the composite ultrafine powder for the ultrahigh-strength concrete accounts for 30% of the mass of the cementing material.
The composite superfine powder for the ultrahigh-strength concrete is obtained by mixing and stirring fly ash microbeads, mineral powder and silica fume uniformly; wherein the fly ash micro-beads are super-fine fly ash micro-beads of Yingrun brand purchased from the market, the mineral powder is granulated blast furnace slag powder purchased from the market, and the silica fume is silicon dioxide super-fine powder purchased from the market.
During the preparation process, the fly ash micro-beads, the mineral powder and the silica fume are prepared according to the following proportion in the table 1:
TABLE 1
The concrete prepared in the table 1 is prepared into a concrete sample by using the composite ultrafine powder, the concrete sample is marked according to the marking mode in the table 1, the electric flux of the sample is measured according to GB/T50082-2009 test method for long-term performance and durability of common concrete, the compression strength and slump of the obtained concrete are tested according to the prior art, and the results are shown in the following table 2:
TABLE 2
The test data in tables 1 and 2 show that the proper mixing proportion of the fly ash micro-beads, the mineral powder and the silica fume is beneficial to improving the comprehensive performance of the concrete; when the using amount of the silica fume is less than 15 percent and the using amount of the fly ash microbeads is more than 60 percent, the compressive strength of the concrete during natural curing for 28 days is lower than 120MPa, the slump reaches more than 24cm, the electric flux is more than 880cc, namely the durability is poor, but the effects of reducing the viscosity of the concrete and improving the workability of the concrete are obvious; when the using amount of the mineral powder is less than 25 percent, the compressive strength, the slump constant and the electric flux of the concrete are not ideal; when the usage amount of the fly ash micro-beads is 50-60%, the mineral powder is 25-30% and the silica fume is 15-20%, the compressive strength of the concrete is high and reaches above 128MPa, the electric flux is less than 800cc, the slump reaches about 22cm, and the comprehensive performance of the concrete is greatly improved.
Test 2: study of Cement replacement test
On the basis of the test 1, replacing cement in the cementing material with 42.5-grade ordinary portland cement or 32.5-grade ordinary portland cement, preparing a concrete sample, and testing the electric flux, the compressive strength and the slump of the concrete sample according to the test method of the test 1, wherein the results are shown in the following tables 3 and 4:
TABLE 342.5-grade ordinary portland cement
Ordinary portland cement of grade 432.5
As shown by the data in tables 2, 3 and 4, it is most appropriate to use a grade 52.5 Portland cement for the cement used in the cement, and it is also verified that: the composite ultrafine powder for the ultra-high-strength concrete is suitable for being combined with 52.5-grade common silicate, can enhance the comprehensive performance of the concrete, is not suitable for being combined with other grades of common silicate, and otherwise, the strength grade of the concrete is influenced, so that the strength of the concrete is poorer, and the performances such as electric flux and the like are influenced, so that the comprehensive quality of a concrete product is poorer; but the proper proportion of the superfine composite powder raw materials is beneficial to improving the strength of the concrete to more than 120MPa, simultaneously ensuring that the electric flux is lower than 900cc, and greatly improving the comprehensive performance of the concrete.
Test 3: research on compressive strength test under different curing times
On the basis of the test 1, the concrete samples of the test 1 were subjected to natural curing for 7d, 28d, 56d and 84d, respectively, and the compression strength (MPa) test was performed, and the results are shown in the following table 5:
TABLE 5
As shown in the test data of FIG. 1, Table 2 and Table 5, after the composite ultrafine powder created by the present invention is added into the cementitious material to prepare concrete, the compressive strength of the concrete is higher when the concrete is naturally cured for 28 days, and the strength of the concrete is increased with the longer curing period in the later period, but gradually becomes slower; meanwhile, under partial mixing proportion, the concrete block with higher compressive strength can be obtained in a short time, and the comprehensive performance of the concrete is greatly improved.
Test 4: research on compression strength change test under different water-gel ratios
On the basis of the test 1, the water-cement ratio in the preparation process is adjusted to prepare a concrete sample, and the concrete compressive strength (MPa) is tested according to the compressive strength test method of the test 1, and the results are shown in the following table 6:
TABLE 6
As shown in the test data of fig. 2 and table 6, when the composite ultrafine powder created by the present invention is added into concrete as a cementing material, the water-cement ratio needs to be controlled within a proper range, otherwise, the strength of the concrete is greatly affected, and the comprehensive performance of the concrete is poor; experimental study shows that: when the composite ultrafine powder created by the invention is added to prepare concrete, the water-cement ratio is properly controlled to be lower than 0.18, and most preferably controlled to be between 0.17 and 0.18, so that the strength of the concrete can be greatly improved, the comprehensive performance of the concrete is improved, and the strength of the concrete reaches about 149 MPa.
Production examples of products：
Example 1
Mixing and stirring the cementing material, machine-made macadam, water and surfactant uniformly, pouring, vibrating and naturally curing for 28 days to obtain concrete; wherein the dosage of the cementing material is 600kg/m3The sand rate was 32%, and the assumed volume weight of the concrete was 2600kg/m3Designing, wherein the dosage of the surfactant accounts for 1.2 percent of the mass of the cementing material, and the water-gel ratio is 0.18; the machine-made broken stone is formed by compounding 65% of broken stone and 35% of rice stone in percentage by mass, the granularity of the broken stone is 10-25mm, and the granularity of the rice stone is 5-10 mm; the adopted surfactant is a polycarboxylic acid high-performance water reducing agent (such as Kojie Point-SS polycarboxylic acid high-performance water reducing agent); the cementing material is composite superfine powder and 52.5 grade for ultra-high strength concreteMixing and uniformly stirring common Portland cement, wherein the composite ultrafine powder for the ultra-high strength concrete accounts for 30 percent of the mass of the cementing material; the mineral powder is 105-grade granulated blast furnace slag powder.
Example 2
Mixing and stirring the cementing material, machine-made macadam, water and surfactant uniformly, pouring, vibrating and naturally curing for 28 days to obtain concrete; wherein the dosage of the cementing material is 700kg/m3The sand rate is 30 percent, and the assumed volume weight of the concrete is 2550kg/m3Designing, wherein the dosage of the surfactant accounts for 1.5 percent of the mass of the cementing material, and the water-gel ratio is 0.18; the machine-made broken stone is formed by compounding 80% of broken stone and 20% of rice stone in percentage by mass, the granularity of the broken stone is 10-25mm, and the granularity of the rice stone is 5-10 mm; the adopted surfactant is a polycarboxylic acid high-performance water reducing agent (such as Kojie Point-SS polycarboxylic acid high-performance water reducing agent); the cementing material is formed by uniformly mixing and stirring composite ultrafine powder for the ultrahigh-strength concrete and 52.5-grade ordinary portland cement, wherein the composite ultrafine powder for the ultrahigh-strength concrete accounts for 40% of the mass of the cementing material; the mineral powder is 105-grade granulated blast furnace slag powder.
Example 3
Mixing and stirring the cementing material, machine-made macadam, water and surfactant uniformly, pouring, vibrating and naturally curing for 28 days to obtain concrete; wherein the dosage of the cementing material is 750kg/m3The sand rate is 30 percent, and the assumed volume weight of the concrete is 2550kg/m3Designing, wherein the dosage of the surfactant accounts for 1.3 percent of the mass of the cementing material, and the water-gel ratio is 0.17; the machine-made broken stone is formed by compounding 75% of broken stone and 25% of rice stone in percentage by mass, the granularity of the broken stone is 10-25mm, and the granularity of the rice stone is 5-10 mm; the adopted surfactant is a polycarboxylic acid high-performance water reducing agent (such as Kojie Point-SS polycarboxylic acid high-performance water reducing agent); the cementing material is formed by uniformly mixing and stirring composite ultrafine powder for the ultrahigh-strength concrete and 52.5-grade ordinary portland cement, wherein the composite ultrafine powder for the ultrahigh-strength concrete accounts for 35% of the mass of the cementing material; the mineral powder is 105-grade granulated blast furnace slag powder.
Example 4
Mixing and stirring the cementing material, machine-made macadam, water and surfactant uniformly, pouring, vibrating and naturally curing for 28 days to obtain concrete; wherein the dosage of the cementing material is 800kg/m3The sand rate was 32%, and the assumed volume weight of the concrete was 2500kg/m3Designing, wherein the dosage of the surfactant accounts for 1.4 percent of the mass of the cementing material, and the water-gel ratio is 0.18; the machine-made broken stone is formed by compounding 75% of broken stone and 25% of rice stone in percentage by mass, the granularity of the broken stone is 10-25mm, and the granularity of the rice stone is 5-10 mm; the adopted surfactant is a polycarboxylic acid high-performance water reducing agent (such as Kojie Point-SS polycarboxylic acid high-performance water reducing agent); the cementing material is formed by uniformly mixing and stirring composite ultrafine powder for the ultrahigh-strength concrete and 52.5-grade ordinary portland cement, wherein the composite ultrafine powder for the ultrahigh-strength concrete accounts for 35% of the mass of the cementing material; the mineral powder is 105-grade granulated blast furnace slag powder.
Example 5
Mixing and stirring the cementing material, machine-made macadam, water and surfactant uniformly, pouring, vibrating and naturally curing for 28 days to obtain concrete; wherein the dosage of the cementing material is 900kg/m3The sand rate was 32%, and the assumed volume weight of the concrete was 2500kg/m3Designing, wherein the dosage of the surfactant accounts for 1.4 percent of the mass of the cementing material, and the water-gel ratio is 0.18; the machine-made broken stone is formed by compounding 85% of broken stone and 15% of rice stone in percentage by mass, the granularity of the broken stone is 10-25mm, and the granularity of the rice stone is 5-10 mm; the adopted surfactant is a polycarboxylic acid high-performance water reducing agent (such as Kojie Point-SS polycarboxylic acid high-performance water reducing agent); the cementing material is formed by uniformly mixing and stirring composite ultrafine powder for the ultrahigh-strength concrete and 52.5-grade ordinary portland cement, wherein the composite ultrafine powder for the ultrahigh-strength concrete accounts for 35% of the mass of the cementing material; the mineral powder is 105-grade granulated blast furnace slag powder.
The products prepared in the above examples 1 to 5 were subjected to volume weight, slump, natural curing 28d compressive strength and electric flux tests, and the results are shown in the following table 7:
TABLE 7
The test data in Table 7 show that the addition amount of the cementing material in the concrete and the quality of the machine-made sand can greatly influence the comprehensive performance of the concrete; the dosage of the cementing material is less than 700kg/m3When the total sand ratio (sand rate) of the machine-made sand to the sand is lower than 32%, the concrete slump constant and the electric flux performance are excellent, but the compressive strength of the concrete reaches 110.9 MPa; and higher than 800kg/m for cementitious materials3When the sand rate is 32%, the concrete slump is higher, the electric flux reaches more than 780cc, and the compressive strength reaches 110.8MPa, so that the comprehensive performance of the concrete is influenced, and the application cost of the cementing material is increased; the dosage of the cementing material is 700-800kg/m3The machine-made broken stone is formed by compounding 70-80% of broken stone and 20-30% of rice stone, so that the slump constant of the concrete is higher than 22.4cm, the electric flux is lower than 770cc, the compressive strength is higher than 128MPa, and the comprehensive performance of the concrete is greatly improved.
The present invention may be practiced in other ways without departing from the spirit and scope of the present invention, which should be determined from the contents of the conventional technical means, common general knowledge and prior art documents in the art.
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 (9)
1. The composite superfine powder for ultrahigh-strength concrete is characterized by comprising the following raw materials, by weight, 50-60 parts of fly ash microbeads, 25-30 parts of mineral powder and 15-20 parts of silica fume.
2. The composite ultrafine powder for ultra-high strength concrete according to claim 1, wherein the raw material components comprise 55 parts by weight of fly ash microbeads, 25 parts by weight of mineral powder and 20 parts by weight of silica fume.
3. The use of composite ultrafine powder for ultra-high strength concrete according to claims 1 and 2, wherein the fly ash microbeads, mineral powder and silica fume are mixed and stirred uniformly to obtain the composite ultrafine powder for ultra-high strength concrete; preparing the composite ultrafine powder for the ultrahigh-strength concrete and cement into a cementing material; the composite ultrafine powder for the ultra-high strength concrete accounts for 30-40% of the total mass of the cementing material; and mixing and stirring the cementing material, machine-made sand, water and a surfactant uniformly.
4. A cementitious material for ultra-high strength concrete, which is characterized by being formed by compounding the composite micropowder for ultra-high strength concrete according to claim 1 or 2 and cement, wherein the composite micropowder for ultra-high strength concrete accounts for 30-40% of the total mass of the cementitious material; the cement is 52.5-grade ordinary portland cement.
5. The cementitious material for ultra-high strength concrete according to claim 4, wherein the composite ultra-fine powder for ultra-high strength concrete accounts for 35% of the total mass of the cementitious material.
6. The ultra-high-strength concrete is characterized by comprising a cementing material, machine-made broken stone, water and a surfactant, wherein the dosage of the cementing material is 700-800kg/m3The sand rate is 30-32%, the dosage of the surfactant accounts for 1.2-1.5% of the mass of the cementing material, and the water-gel ratio is 0.17-0.18; the cementing material is formed by compounding the composite ultrafine powder for the ultra-high strength concrete and cement according to claim 1 or 2, wherein the composite ultrafine powder for the ultra-high strength concrete accounts for 30-40% of the total mass of the cementing material; the cement is 52.5-grade ordinary portland cement.
7. The ultra-high strength concrete as claimed in claim 6, wherein said machine-made crushed stone is composed of 70-80% by mass of crushed stone and 20-30% by mass of rice stone; wherein: the granularity of the broken stone is 10-25mm, and the granularity of the rice stone is 5-10 mm.
8. The ultra-high-strength concrete according to claim 6 or 7, wherein after natural curing for 28d, the compressive strength of the ultra-high-strength concrete reaches 128-149.6MPa, and the electric flux is less than or equal to 800 cc.
9. The method for preparing ultra-high-strength concrete according to any one of claims 6 to 8, comprising the steps of:
(1) preparing composite superfine powder: mixing and stirring the fly ash micro-beads, the mineral powder and the silica fume uniformly;
(2) preparing a cementing material: the composite ultrafine powder is compounded with cement;
(3) preparing the ultra-high strength concrete: mixing the machine-made macadam, the cementing material, the surfactant and the water, uniformly stirring, pouring, vibrating and naturally curing to obtain the concrete.
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113968703A (en) * | 2021-10-28 | 2022-01-25 | 明阳智慧能源集团股份公司 | Offshore wind power floating type foundation C115-C140 ultrahigh-performance self-compacting concrete |
| CN113998960A (en) * | 2021-12-13 | 2022-02-01 | 青岛伟力环保建材有限公司 | Modified micro-nano composite superfine admixture high-durability anti-crack concrete and preparation method thereof |
| CN114276073A (en) * | 2021-05-25 | 2022-04-05 | 山西黄河前沿新材料研究院有限公司 | Light high-performance concrete for fabricated building and preparation method thereof |
| CN116239328A (en) * | 2023-02-21 | 2023-06-09 | 北京科宁丰外加剂有限公司 | High-durability mixture special for airport pavement cement concrete and preparation method thereof |
| CN118005352A (en) * | 2024-02-03 | 2024-05-10 | 广州兴业混凝土搅拌有限公司 | Composite cementing material for low-viscosity ultra-high-strength concrete and preparation method thereof |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0696558B1 (en) * | 1994-08-12 | 1998-11-25 | Dyckerhoff Aktiengesellschaft | Superfine cement binder mixture, process for its preparation and device for carrying out the process |
| CN105294006A (en) * | 2015-10-23 | 2016-02-03 | 上海建工集团股份有限公司 | C100-C120 graded ultrahigh-strength concrete having high workability |
| CN105819718A (en) * | 2015-01-05 | 2016-08-03 | 中国建筑材料科学研究总院 | Concrete high-strength admixture, cement mixture and non-autoclaved ultra-high strength concrete product |
| CN107651890A (en) * | 2017-09-13 | 2018-02-02 | 无锡市交通工程有限公司 | A kind of concrete formulation and concrete road laying method |
-
2020
- 2020-01-08 CN CN202010018763.4A patent/CN111792857A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0696558B1 (en) * | 1994-08-12 | 1998-11-25 | Dyckerhoff Aktiengesellschaft | Superfine cement binder mixture, process for its preparation and device for carrying out the process |
| CN105819718A (en) * | 2015-01-05 | 2016-08-03 | 中国建筑材料科学研究总院 | Concrete high-strength admixture, cement mixture and non-autoclaved ultra-high strength concrete product |
| CN105294006A (en) * | 2015-10-23 | 2016-02-03 | 上海建工集团股份有限公司 | C100-C120 graded ultrahigh-strength concrete having high workability |
| CN107651890A (en) * | 2017-09-13 | 2018-02-02 | 无锡市交通工程有限公司 | A kind of concrete formulation and concrete road laying method |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114276073A (en) * | 2021-05-25 | 2022-04-05 | 山西黄河前沿新材料研究院有限公司 | Light high-performance concrete for fabricated building and preparation method thereof |
| CN113968703A (en) * | 2021-10-28 | 2022-01-25 | 明阳智慧能源集团股份公司 | Offshore wind power floating type foundation C115-C140 ultrahigh-performance self-compacting concrete |
| CN113998960A (en) * | 2021-12-13 | 2022-02-01 | 青岛伟力环保建材有限公司 | Modified micro-nano composite superfine admixture high-durability anti-crack concrete and preparation method thereof |
| CN116239328A (en) * | 2023-02-21 | 2023-06-09 | 北京科宁丰外加剂有限公司 | High-durability mixture special for airport pavement cement concrete and preparation method thereof |
| CN118005352A (en) * | 2024-02-03 | 2024-05-10 | 广州兴业混凝土搅拌有限公司 | Composite cementing material for low-viscosity ultra-high-strength concrete and preparation method thereof |
| CN118005352B (en) * | 2024-02-03 | 2024-08-16 | 广州兴业混凝土搅拌有限公司 | Composite cementing material for low-viscosity ultra-high-strength concrete and preparation method thereof |
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