CN114573291A - Limestone powder high-strength concrete and preparation method thereof - Google Patents
Limestone powder high-strength concrete and preparation method thereof Download PDFInfo
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- CN114573291A CN114573291A CN202210179955.2A CN202210179955A CN114573291A CN 114573291 A CN114573291 A CN 114573291A CN 202210179955 A CN202210179955 A CN 202210179955A CN 114573291 A CN114573291 A CN 114573291A
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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
- 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
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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
- 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
- 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
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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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- 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
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- 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 application relates to limestone powder high-strength concrete and a preparation method thereof, relating to the technical field of building materials. The feed is prepared from the following raw materials in parts by weight: 500 parts of ordinary portland cement, 520 parts of fine aggregate, 460 parts of coarse aggregate, 1300 parts of ultrafine limestone powder, 190 parts of water, 4-8 parts of a water reducing agent and 30-50 parts of modified silica fume, wherein the modified silica fume is prepared from raw materials comprising a water repellent agent, a dispersing agent, triethylene tetramine, silica fume and water by processes of heating, cooling, drying and the like. This application has the effect that promotes concrete frost resistance.
Description
Technical Field
The application relates to the technical field of building materials, in particular to limestone powder high-strength concrete and a preparation method thereof.
Background
As the slag and the fly ash are increasingly used in the concrete industry, the demand of the slag and the fly ash is increasingly large, the slag and the fly ash both belong to nonrenewable resources, and the fly ash and the slag resources are not uniformly distributed in China, so that the phenomenon of off-sale even occurs in partial areas. Therefore, it is important to find suitable materials to replace the mineral admixtures commonly used at present in concrete.
Limestone resources in China are widely distributed, the limestone resources are low in price and easy to grind and convenient to transport, and limestone powder serving as a mineral admixture to replace cement is applied to concrete, so that an effective way is provided for solving the situation of short supply of the existing mineral admixture and reducing the production cost of the concrete.
However, the limestone powder added into the concrete belongs to inactive components and does not react with water chemically, and after the limestone powder is added into the concrete, the frost resistance of the concrete can be influenced, and the frost resistance of the concrete can be negatively influenced.
Disclosure of Invention
In order to improve the frost resistance of concrete, the application provides limestone powder high-strength concrete and a preparation method thereof.
In a first aspect, the limestone powder high-strength concrete provided by the application adopts the following technical scheme:
the limestone powder high-strength concrete is prepared from the following raw materials in parts by weight: 500 parts of ordinary portland cement, 520 parts of fine aggregate, 460 parts of coarse aggregate, 1300 parts of ultrafine limestone powder, 190 parts of water, 4-8 parts of a water reducing agent and 30-50 parts of modified silica fume, wherein the modified silica fume is prepared from raw materials comprising a water repellent agent, a dispersing agent, triethylene tetramine, silica fume and water by processes of heating, cooling, drying and the like.
By adopting the technical scheme, in the application, the superfine limestone powder and the modified silica fume are used for replacing part of cement. Limestone powder can be used as a nucleation matrix of hydrated calcium silicate, so that nucleation barrier is reduced, and early cement hydration rate is accelerated; but also because the activity of the limestone powder is extremely low, the total porosity, coarse capillary pores and porosity of pores of the concrete are increased, and a hardened concrete structure partially densely filled by physics is easy to be damaged under the environmental influence of freeze-thaw cycles, so that the frost resistance of the concrete is deteriorated.
The silica fume has high pozzolan activity and can be used as a crystal nucleus required by cement hydration in the cement hydration process so as to accelerate the cement hydration, and the main component of silica fume in the silica fume can react with calcium hydroxide in a cement hydration product to cause the cement to undergo a secondary hydration reaction, wherein the secondary hydration reaction generates hydrated calcium silicate gel which is more gelatinous than the calcium hydroxide, consumes the silicon hydroxide, generates low-alkalinity hydrated calcium silicate with higher strength and higher stability, and enhances the binding power of a cement stone and an aggregate interface; meanwhile, the silica fume reduces the number of coarse pores and capillary pores in the concrete structure, increases the number of superfine pores, and has a large adsorption effect on water, so that the freezing point of water is lowered, the freeze thawing process is delayed, the negative influence of destructive stress on the concrete is reduced, and the frost resistance of the concrete is improved.
However, the silica fume is easy to agglomerate in a concrete system due to large specific surface area, and cannot be uniformly dispersed in concrete together with limestone powder, so that the negative influence of the limestone powder on the frost resistance of the concrete is improved.
In conclusion, the frost resistance of the limestone powder high-strength concrete prepared by the formula is improved.
Optionally, with the modified silica fume as a reference, the modified silica fume is prepared from the following raw materials in parts by weight:
10-25 parts of a water repellent agent;
10-20 parts of triethylene tetramine;
50-70 parts of silica fume;
3-5 parts of a dispersing agent;
and a proper amount of water.
In the present application, "a proper amount of water" means a degree that the above raw materials can be stirred uniformly.
By adopting the technical scheme, the silica fume is uniformly dispersed in the system by the acrylic acid and the maleic anhydride, the secondary alcohol polyoxyethylene ether and the methacryloxypropyltrimethoxysilane coupling agent are promoted by the triethylene tetramine to form a film on the surface of the silica fume, and finally a hydrophobic film is formed on the surface of the silica fume, so that the dispersion uniformity of the modified silica fume in a concrete system is improved, the raw materials are easily obtained, and the preparation is convenient.
Optionally, the hydrophobic agent is selected from any one or two of secondary alcohol polyoxyethylene ether and methacryloxypropyltrimethoxy silane coupling agent, and the dispersing agent is selected from any one or two of acrylic acid and maleic anhydride.
By adopting the technical scheme, various hydrophobing agents and various dispersing agents are adopted for dispersing, so that various properties of the prepared modified silica fume are improved.
Optionally, the modified silica fume is prepared by a method comprising the following steps: adding acrylic acid, maleic anhydride, secondary alcohol polyoxyethylene ether and methacryloxypropyl trimethoxy silane coupling agent into heated water to obtain a liquid mixture, adding triethylene tetramine and silica fume into the liquid mixture to obtain a solid-liquid mixture, stirring, cooling, drying and crushing after stirring.
By adopting the technical scheme, the acrylic acid, the maleic anhydride, the secondary alcohol polyoxyethylene ether and the methacryloxypropyl trimethoxy silane coupling agent are added into continuously heated water, the silica fume and the triethylene tetramine are added, the acrylic acid and the maleic anhydride disperse the silica fume in a system, so that the silica fume is fully wrapped by the hydrophobic agent secondary alcohol polyoxyethylene ether and the methacryloxypropyl trimethoxy silane coupling agent, and a hydrophobic film is formed on the surface of the silica fume under the action of the curing agent triethylene tetramine after cooling, so that the modified silica fume is obtained.
Optionally, in the preparation process of the modified silica fume, the heating temperature is 60-100 ℃, the stirring time is 5-15min, the drying temperature is 40-60 ℃, and the drying time is 100-200 min.
By adopting the technical scheme, the combination of the hydrophobic membrane and the surface of the silica fume is more stable.
Optionally, the specific surface area of the silica fume is 20000-25000m2/kg。
By adopting the technical scheme, the silica fume has small particle size, and can fill relatively large pores of cement particles, reduce the volume of the pores and improve the frost resistance of concrete; the silica fume has large specific surface area, promotes the capability of the silica fume and the cement hydration product calcium hydroxide to react to generate hydrated calcium silicate, and improves the strength and the stability of the concrete.
Optionally, the raw materials for preparing the limestone powder high-strength concrete further comprise 5-15 parts of carboxymethyl cellulose and 2-10 parts of microcrystalline cellulose.
By adopting the technical scheme, the limestone powder can be uniformly dispersed in the concrete system by using the microcrystalline cellulose, so that the dispersion uniformity of the limestone powder and the modified silica fume in the concrete system is improved, the binding capacity of the modified silica fume and the limestone powder is further promoted, the negative influence of the limestone powder on the performance of the concrete is reduced, and the frost resistance of the concrete is improved.
Optionally, the limestone powder is ultrafine limestone powder, and the specific surface of the ultrafine limestone powderThe area is 1000-2/kg。
By adopting the technical scheme, the superfine limestone powder has large specific surface area, and the fine capillary porosity of the concrete can be reduced to a great extent.
In a second aspect, the application provides a method for preparing limestone powder high-strength concrete, comprising the following steps:
s1: mixing and stirring water and a water reducing agent uniformly to obtain a first mixture;
s2: mixing and stirring the Portland cement, the superfine limestone powder and the modified silica fume uniformly to obtain a second mixture;
s3: uniformly mixing the first mixture and the second mixture, and stirring to obtain a third mixture;
s4: and mixing and stirring the fine aggregate, the coarse aggregate and the third mixture to prepare the limestone powder high-strength concrete.
By adopting the technical scheme, the raw materials are mixed in batches, so that the raw materials are fully mixed, the raw materials are fully exerted, and are matched for use together to prepare the limestone powder high-strength concrete.
Optionally, in step S1, a step of mixing 5 to 15 parts of carboxymethyl cellulose with water and a water reducing agent is further included, and in step S2, a step of mixing 2 to 10 parts of microcrystalline cellulose with portland cement, ultrafine limestone powder, and modified silica fume is further included.
By adopting the technical scheme, the carboxymethyl cellulose and the microcrystalline cellulose act together to improve the dispersion uniformity of the ultrafine limestone powder in the concrete.
In summary, the present application has the following beneficial effects:
1. by adding the modified silica fume into the limestone powder high-strength concrete, the dispersion effect of the silica fume in a concrete system is improved, the negative influence of the limestone powder on the frost resistance of the concrete is reduced by the modified silica fume, the frost resistance of the concrete is improved, in addition, the silica fume belongs to industrial waste, the silica fume is matched with the limestone powder to replace fly ash and slag, the concrete cost is further reduced, and the concrete manufacturing process is more environment-friendly.
2. By adding microcrystalline cellulose and carboxymethyl cellulose into the concrete, the dispersion uniformity of the limestone powder in the concrete is improved, and the negative influence of the modified silica fume on the frost resistance of the concrete is better improved.
Detailed Description
The present application will be described in further detail with reference to examples.
Examples of production of modified silica fume
Preparation example 1
A modified silica fume is prepared by taking 18kg of secondary alcohol polyoxyethylene ether, 4kg of maleic anhydride and 80-100kg of water, adding the water to completely dissolve the above substances, adding the hot water to dissolve the secondary alcohol polyoxyethylene ether and the maleic anhydride to obtain a liquid mixture, adding 60kg of silica fume and 16kg of triethylene tetramine into the liquid mixture, continuously stirring, keeping the heating temperature at 80 ℃ in the whole process, stirring for 10min to obtain a solid-liquid mixture, then cooling at room temperature, drying at 50 ℃ for 120min, crushing and grinding to obtain the modified silica fume.
Preparation example 2
A modified silica fume is prepared by taking 9kg of secondary alcohol polyoxyethylene ether, 9kg of methacryloxypropyl trimethoxy silane coupling agent, 4kg of maleic anhydride and 80-100kg of water, adding water to completely dissolve the above substances, adding 60kg of silica fume and 16kg of triethylene tetramine into a liquid mixture obtained by heating water to dissolve the secondary alcohol polyoxyethylene ether, the methacryloxypropyl trimethoxy silane coupling agent and the maleic anhydride, continuously stirring, keeping the heating temperature at 80 ℃ in the whole process, stirring for 10min to obtain a solid-liquid mixture, cooling at room temperature, drying at 50 ℃ for 120min, crushing and grinding to obtain the modified silica fume.
Preparation example 3
A modified silica fume is prepared by taking 18kg of secondary alcohol polyoxyethylene ether, 2kg of acrylic acid, 2kg of maleic anhydride and 80-100kg of water, adding the water to completely dissolve the above substances, adding hot water to dissolve the secondary alcohol polyoxyethylene ether, the acrylic acid and the maleic anhydride to obtain a liquid mixture, adding 60kg of silica fume and 16kg of triethylene tetramine into the liquid mixture, continuously stirring, keeping the heating temperature at 80 ℃ in the whole process, stirring for 10min to obtain a solid-liquid mixture, then cooling at room temperature, drying at 50 ℃, drying for 120min, crushing and grinding to obtain the modified silica fume.
Preparation example 4
A modified silica fume is prepared by taking 9kg of secondary alcohol polyoxyethylene ether, 9kg of methacryloxypropyl trimethoxy silane coupling agent, 2kg of acrylic acid, 2kg of maleic anhydride and 80-100kg of water, adding water to completely dissolve the above substances, adding 60kg of silica fume and 16kg of triethylene tetramine into a liquid mixture, continuously stirring, keeping the heating temperature at 80 ℃ in the whole process, stirring for 10min to obtain a solid-liquid mixture, cooling at room temperature, drying at 50 ℃ for 120min, crushing and grinding to obtain the modified silica fume.
Preparation example 5
A modified silica fume is prepared by taking 18g of methacryloxypropyl trimethoxy silane coupling agent, 4kg of maleic anhydride and 80-100kg of water, adding the water to completely dissolve the materials, adding hot water to dissolve secondary alcohol polyoxyethylene ether, methacryloxypropyl trimethoxy silane coupling agent, acrylic acid and maleic anhydride to obtain a liquid mixture, adding 60kg of silica fume and 16kg of triethylene tetramine into the liquid mixture, continuously stirring, keeping the heating temperature at 80 ℃ in the whole process, stirring for 10min to obtain a solid-liquid mixture, cooling at room temperature, drying at 50 ℃, drying for 120min, crushing and grinding to obtain the modified silica fume.
Preparation example 6
A modified silica fume is prepared by taking 18kg of secondary alcohol polyoxyethylene ether, 4kg of acrylic acid and 80-100kg of water, adding the water to completely dissolve the above substances, adding the hot water to dissolve the secondary alcohol polyoxyethylene ether and the acrylic acid to obtain a liquid mixture, adding 60kg of silica fume and 16kg of triethylene tetramine into the liquid mixture, continuously stirring, keeping the heating temperature at 80 ℃ in the whole process, stirring for 10min to obtain a solid-liquid mixture, then cooling at room temperature, drying at 50 ℃ for 120min, crushing and grinding to obtain the modified silica fume.
Preparation example 7
A modified silica fume is prepared by taking 10kg of secondary alcohol polyoxyethylene ether, 3kg of maleic anhydride and 80-100kg of water, adding the water to completely dissolve the above substances, adding the hot water to dissolve the secondary alcohol polyoxyethylene ether and the maleic anhydride to obtain a liquid mixture, adding 50kg of silica fume and 10kg of triethylene tetramine into the liquid mixture, continuously stirring, keeping the heating temperature at 80 ℃ in the whole process, stirring for 10min to obtain a solid-liquid mixture, then cooling at room temperature, drying at 50 ℃ for 120min, crushing and grinding to obtain the modified silica fume.
Preparation example 8
A modified silica fume is prepared by taking 25kg of secondary alcohol polyoxyethylene ether, 5kg of maleic anhydride and 80-100kg of water, adding the water to completely dissolve the above substances, adding the hot water to dissolve the secondary alcohol polyoxyethylene ether and the maleic anhydride to obtain a liquid mixture, adding 70kg of silica fume and 20kg of triethylene tetramine into the liquid mixture, continuously stirring, keeping the heating temperature at 80 ℃ in the whole process, stirring for 10min to obtain a solid-liquid mixture, then cooling at room temperature, drying at 50 ℃ for 120min, crushing and grinding to obtain the modified silica fume.
Preparation example 9
A modified silica fume was different from that of production example 1 in that in the heating step, heating was carried out to 60 ℃ to obtain a modified silica fume.
Preparation example 10
A modified silica fume was different from that of production example 1 in that, in the heating step, the heating temperature was maintained at 100 ℃ to obtain a modified silica fume.
Examples
Example 1
The limestone powder high-strength concrete is prepared from the following raw materials in parts by weight: 450kg of ordinary portland cement, 500kg of fine aggregate, 1200kg of coarse aggregate, 60kg of superfine limestone powder, 170kg of water, 6kg of water reducing agent and 40kg of modified silica fume, wherein the modified silica fume is prepared from preparation example 1, the fine aggregate is machine-made sand, the coarse aggregate is commercially available coarse aggregate with the particle size of 5-25mm, and the cement is trumpet shell brand P.0.42.5.
The preparation method of the limestone powder high-strength concrete comprises the following steps:
s1: mixing and stirring water and a water reducing agent uniformly to obtain a first mixture;
s2: mixing and stirring the Portland cement, the limestone powder and the modified silica fume uniformly to obtain a second mixture;
s3: uniformly mixing the first mixture and the second mixture, and stirring to obtain a third mixture;
s4: and mixing and stirring the fine aggregate, the coarse aggregate and the third mixture to prepare the limestone powder high-strength concrete.
Examples 2 to 10
The limestone powder high-strength concrete is different from the concrete in the embodiment 1 in that the modified silica fume prepared in the preparation examples 2-10 is adopted in sequence.
Example 11
The limestone powder high-strength concrete is different from the concrete in the embodiment 1 in that the limestone powder high-strength concrete is prepared from the following raw materials in parts by weight: 400kg of ordinary portland cement, 460kg of fine aggregate, 1000kg of coarse aggregate, 50kg of superfine limestone powder, 150kg of water, 4kg of water reducing agent and 30kg of modified silica fume.
Example 12
The limestone powder high-strength concrete is different from the concrete in the embodiment 1 in that the limestone powder high-strength concrete is prepared from the following raw materials in parts by weight: 500kg of ordinary portland cement, 520kg of fine aggregate, 1300kg of coarse aggregate, 70kg of superfine limestone powder, 190kg of water, 8kg of water reducing agent and 50kg of modified silica fume.
Example 13
The difference between limestone powder high-strength concrete and the embodiment 1 is that 10kg of carboxymethyl cellulose is used in the step S1.
Example 14
The difference between limestone powder high-strength concrete and the embodiment 1 is that 6kg of microcrystalline cellulose is used in the step S2.
Example 15
A limestone powder high-strength concrete is different from that of example 1 in that 5kg of carboxymethyl cellulose and water are used in the step S1, and 3kg of microcrystalline cellulose is used in the step S2.
Comparative example
Comparative example 1
The limestone powder high-strength concrete is different from the concrete in example 1 in that modified silica fume is not added.
Comparative example 2
The limestone powder high-strength concrete is different from the concrete in the embodiment 1 in that modified silica fume is replaced by equal-quality silica fume.
Comparative example 3
The difference between the limestone powder high-strength concrete and the concrete in the embodiment 1 is that the mass of the modified silica fume is 10 kg.
Comparative example 4
The difference between the limestone powder high-strength concrete and the concrete in the embodiment 1 is that the mass of the modified silica fume is 70 kg.
Performance test
Detection method
1. Concrete strength detection
The concrete prepared in examples 1-15 and comparative examples 1-4 was subjected to a 28d compressive strength test according to GB/T50081-2002 Standard test methods for mechanical Properties of general concrete. Continuously and uniformly loading in the test process, wherein when the strength grade of concrete is less than C30, the loading speed is 0.3-0.5 MPa per second; when the strength grade of the concrete is more than or equal to C30 and less than C60, 0.5-0.8 MPa per second is adopted; when the strength grade of the concrete is more than or equal to C60, 0.8-1.0 MPa per second is taken. When the test piece begins to deform sharply near failure, adjustment of the tester throttle should be stopped until failure, and the failure load recorded in table 1.
2. Detection of concrete frost resistance
The concrete produced in examples 1 to 15 and comparative examples 1 to 4 were subjected to a freezing resistance test. The test method is carried out according to a slow freezing method in GB/T50082-2009 test method standards for long-term performance and durability of common concrete, and when the melting cycle of a freezing surface occurs in one of the following three conditions, the test can be stopped: firstly, reaching specified cycle times; secondly, the loss rate of the compressive strength of the test piece reaches 25 percent; and the mass loss rate of the test piece reaches 5 percent.
Table 1 shows the results of tests on the compressive strength and the frost resistance of the recycled concrete obtained in examples 1 to 15 and comparative examples 1 to 4
Combining example 1, comparative examples 1-2 and table 1, it can be seen that the concrete 28d without the modified silica fume in comparative example 1 has the lowest strength, and the highest mass loss rate and highest compressive strength loss rate after 300 freeze-thaw cycles; after the common silica fume with the same quality as that in the comparative example 1 is added in the comparative example 2, compared with the comparative example 1, the strength of the concrete 28d is improved, and the quality loss rate and the compressive strength loss rate after 300 times of freeze-thaw cycles are reduced; the strength of the concrete 28d added with the modified silica fume in the embodiment 1 is the highest among the three, and the mass loss rate and the compressive gas strength loss rate after 300 times of freeze-thaw cycle are the lowest among the three; the modified silica fume can be compounded with the limestone powder, so that the influence of the limestone powder on the mechanical property of the concrete is reduced, and the frost resistance of the concrete is improved, probably because the modified silica fume is more uniformly dispersed in the concrete and has stronger compatibility with the concrete, the modified silica fume is preferably selected.
It can be seen from the combination of example 1, comparative examples 3-4 and table 1 that when too much modified silica fume and too little modified silica fume are added, the 28d compressive strength of the concrete is reduced, and the mass loss rate and the compressive strength loss rate after 300 freeze-thaw cycles are increased, which indicates that the concrete is negatively affected by a small amount or an excessive amount of the modified silica fume, this is probably because when the modified silica fume is small in amount, the modified silica fume cannot compensate for the negative effect of the limestone powder on the concrete, and when an excessive amount of the modified silica fume is added, because the specific surface area of the modified silica fume is far larger than that of the limestone powder, excessive modified silica fume is added into concrete to adsorb concrete mixing water, the water participating in hydration is reduced, the concrete is insufficiently hydrated, cracks are easily generated, and the mechanical property and the frost resistance of the concrete are further influenced, so that the mixing amount of the modified silica fume is preferably 40 kg.
It can be seen from the combination of examples 1-8, 11-12 and table 1 that the concrete 28d of example 4 has the highest compressive strength, and the mass loss rate and the loss rate of the compressive gas strength after 300 freeze-thaw cycles are the lowest, which indicates that acrylic acid and maleic anhydride can effectively improve the dispersion effect of silica fume in the preparation system, and the secondary alcohol polyoxyethylene ether and methacryloxypropyltrimethoxysilane coupling agent can form a hydrophobic film on the surface of silica fume to a great extent by compounding, so as to improve the dispersion uniformity of silica fume in the concrete, so that the modified silica fume compensates the negative effects of the limestone powder on the strength and the frost resistance of the concrete, and therefore, the acrylic acid and maleic anhydride are preferably added for matching, and the secondary alcohol polyoxyethylene ether and the methacryloxypropyltrimethoxysilane coupling agent for matching are preferably added for matching and are applied to the preparation process of the modified silica fume.
It can be seen from the combination of examples 1, 9-10 and table 1 that when the preparation temperature of the modified silica fume is too high or too low, the 28d compressive strength of the concrete is reduced, and the mass loss rate and the loss rate of the compressive strength after 300 times of freeze-thaw cycles are increased, which may be because when the temperature is too high or too low, the secondary alcohol polyoxyethylene ether and the methacryloxypropyltrimethoxysilane coupling agent are not favorable for forming a hydrophobic film on the surface of the silica fume, so that the dispersion uniformity of the modified silica fume in the concrete is influenced, and the modified silica fume is further influenced to improve the negative influence of the limestone powder on the concrete, therefore, the preparation temperature of the modified silica fume is preferably 80 ℃.
It can be seen by combining examples 1, 13-15 and table 1 that after adding carboxymethylcellulose and microcrystalline cellulose in the concrete preparation process, the 28d compressive strength of the concrete is increased, and the mass loss rate and the compressive air strength loss rate after 300 times of freeze-thaw cycles are reduced, because by using carboxymethylcellulose and microcrystalline cellulose, the limestone powder can be uniformly dispersed in the concrete system, the dispersion uniformity of the limestone powder and modified silica fume in the concrete system is improved, the binding capacity of the modified silica fume and limestone powder is further promoted, the negative influence of the limestone powder on the concrete performance is reduced, and thus the frost resistance of the concrete is improved, and therefore, the carboxymethylcellulose and microcrystalline cellulose are preferably added in the concrete preparation process.
The present embodiment is only for explaining the present application, and it is not limited to the present application, and those skilled in the art can make modifications of the present embodiment without inventive contribution as needed after reading the present specification, but all of them are protected by patent law within the scope of the claims of the present application.
Claims (10)
1. The limestone powder high-strength concrete is characterized by being prepared from the following raw materials in parts by weight: 400-500 parts of ordinary portland cement, 460-520 parts of fine aggregate, 1000-1300 parts of coarse aggregate, 50-70 parts of ultrafine limestone powder, 190 parts of water, 4-8 parts of a water reducing agent and 30-50 parts of modified silica fume, wherein the modified silica fume is prepared from raw materials comprising a hydrophobing agent, a dispersing agent, triethylene tetramine, silica fume and water by processes of heating, cooling, drying and the like.
2. The limestone powder high-strength concrete as claimed in claim 1, wherein the modified silica fume is prepared from the following raw materials in parts by weight, with reference to the modified silica fume:
10-25 parts of a water repellent agent;
10-20 parts of triethylene tetramine;
50-70 parts of silica fume;
3-5 parts of a dispersing agent;
and a proper amount of water.
3. The limestone powder high-strength concrete as claimed in claim 2, which is characterized in that: the hydrophobic agent is selected from any one or two of secondary alcohol polyoxyethylene ether and methacryloxypropyltrimethoxy silane coupling agent, and the dispersing agent is selected from any one or two of acrylic acid and maleic anhydride.
4. The limestone powder high-strength concrete as claimed in claim 2, wherein the modified silica fume is prepared by a method comprising the following steps: adding acrylic acid, maleic anhydride, secondary alcohol polyoxyethylene ether and methacryloxypropyltrimethoxysilane coupling agent into heated water to obtain a liquid mixture, adding triethylene tetramine and silica fume into the liquid mixture to obtain a solid-liquid mixture, stirring, cooling, drying and crushing.
5. The limestone powder high-strength concrete as claimed in claim 4, which is characterized in that: in the preparation process of the modified silica fume, the heating temperature is 60-100 ℃, the stirring time is 5-15min, the drying temperature is 40-60 ℃, and the drying time is 100-200 min.
6. The limestone powder high-strength concrete as claimed in claim 2, which is characterized in that: the specific surface area of the silica fume is 20000-25000m 2/kg.
7. The limestone powder high-strength concrete as claimed in claim 1, which is characterized in that: the preparation raw materials of the limestone powder high-strength concrete also comprise 5-15 parts of carboxymethyl cellulose and 2-10 parts of microcrystalline cellulose.
8. The limestone powder high-strength concrete as claimed in claim 1, which is characterized in that: the limestone powder is ultrafine limestone powder, and the specific surface area of the ultrafine limestone powder is 1000-2500m 2/kg.
9. The method for preparing limestone powder high-strength concrete according to any one of claims 1 to 5 and 7 to 8, which is characterized by comprising the following steps:
s1: mixing and stirring water and a water reducing agent uniformly to obtain a first mixture;
s2: mixing and stirring the Portland cement, the limestone powder and the modified silica fume uniformly to obtain a second mixture;
s3: uniformly mixing the first mixture and the second mixture, and stirring to obtain a third mixture;
s4: and mixing and stirring the fine aggregate, the coarse aggregate and the third mixture to prepare the limestone powder high-strength concrete.
10. The method for preparing limestone powder high-strength concrete according to claim 9, characterized in that: in step S1, the method further comprises a step of mixing 5-15 parts of carboxymethyl cellulose with water and a water reducing agent, and in step S2, the method further comprises a step of mixing 2-10 parts of microcrystalline cellulose with portland cement, ultrafine limestone powder and modified silica fume.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114988740A (en) * | 2022-07-06 | 2022-09-02 | 重庆国浩永固新型建材有限公司 | Anti-mud admixture and preparation method and application thereof |
| CN115231849A (en) * | 2022-06-14 | 2022-10-25 | 北京金隅水泥节能科技有限公司 | Additive for decorative concrete, preparation method thereof and decorative concrete |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR101608018B1 (en) * | 2015-12-11 | 2016-03-31 | 우성안전 주식회사 | Method of repairing and protecting surface of concrete structure |
| CN108249849A (en) * | 2018-01-16 | 2018-07-06 | 云南交投集团公路建设有限公司 | A kind of high agstone volume green concrete |
| CN112939499A (en) * | 2021-01-29 | 2021-06-11 | 南京工业大学 | Preparation method and application of modified silica fume material |
-
2022
- 2022-02-25 CN CN202210179955.2A patent/CN114573291A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR101608018B1 (en) * | 2015-12-11 | 2016-03-31 | 우성안전 주식회사 | Method of repairing and protecting surface of concrete structure |
| CN108249849A (en) * | 2018-01-16 | 2018-07-06 | 云南交投集团公路建设有限公司 | A kind of high agstone volume green concrete |
| CN112939499A (en) * | 2021-01-29 | 2021-06-11 | 南京工业大学 | Preparation method and application of modified silica fume material |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115231849A (en) * | 2022-06-14 | 2022-10-25 | 北京金隅水泥节能科技有限公司 | Additive for decorative concrete, preparation method thereof and decorative concrete |
| CN114988740A (en) * | 2022-07-06 | 2022-09-02 | 重庆国浩永固新型建材有限公司 | Anti-mud admixture and preparation method and application thereof |
| CN114988740B (en) * | 2022-07-06 | 2023-08-22 | 重庆国浩永固新型建材有限公司 | Mud-resistant admixture and preparation method and application thereof |
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