CN115417642A - Low-carbon concrete and preparation method thereof - Google Patents
Low-carbon concrete and preparation method thereof Download PDFInfo
- Publication number
- CN115417642A CN115417642A CN202211148726.0A CN202211148726A CN115417642A CN 115417642 A CN115417642 A CN 115417642A CN 202211148726 A CN202211148726 A CN 202211148726A CN 115417642 A CN115417642 A CN 115417642A
- Authority
- CN
- China
- Prior art keywords
- parts
- concrete
- low
- fine aggregate
- micro powder
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
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
- C04B14/00—Use of inorganic materials as fillers, e.g. pigments, for mortars, concrete or artificial stone; Treatment of inorganic materials specially adapted to enhance their filling properties in mortars, concrete or artificial stone
- C04B14/02—Granular materials, e.g. microballoons
- C04B14/04—Silica-rich materials; Silicates
- C04B14/10—Clay
- C04B14/106—Kaolin
-
- 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
- C04B18/00—Use of agglomerated or waste materials or refuse as fillers for mortars, concrete or artificial stone; Treatment of agglomerated or waste materials or refuse, specially adapted to enhance their filling properties in mortars, concrete or artificial stone
- C04B18/04—Waste materials; Refuse
- C04B18/06—Combustion residues, e.g. purification products of smoke, fumes or exhaust gases
- C04B18/08—Flue dust, i.e. fly ash
-
- 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
- C04B18/00—Use of agglomerated or waste materials or refuse as fillers for mortars, concrete or artificial stone; Treatment of agglomerated or waste materials or refuse, specially adapted to enhance their filling properties in mortars, concrete or artificial stone
- C04B18/04—Waste materials; Refuse
- C04B18/14—Waste materials; Refuse from metallurgical processes
- C04B18/146—Silica fume
-
- 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
- C04B18/00—Use of agglomerated or waste materials or refuse as fillers for mortars, concrete or artificial stone; Treatment of agglomerated or waste materials or refuse, specially adapted to enhance their filling properties in mortars, concrete or artificial stone
- C04B18/04—Waste materials; Refuse
- C04B18/16—Waste materials; Refuse from building or ceramic industry
-
- 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
- C04B18/00—Use of agglomerated or waste materials or refuse as fillers for mortars, concrete or artificial stone; Treatment of agglomerated or waste materials or refuse, specially adapted to enhance their filling properties in mortars, concrete or artificial stone
- C04B18/04—Waste materials; Refuse
- C04B18/18—Waste materials; Refuse organic
- C04B18/20—Waste materials; Refuse organic from macromolecular compounds
- C04B18/22—Rubber, e.g. ground waste tires
-
- 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
- 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
- C04B40/0028—Aspects relating to the mixing step of the mortar preparation
- C04B40/0039—Premixtures of ingredients
- C04B40/0046—Premixtures of ingredients characterised by their processing, e.g. sequence of mixing the ingredients when preparing the premixtures
-
- 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
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Ceramic Engineering (AREA)
- Structural Engineering (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- Civil Engineering (AREA)
- Environmental & Geological Engineering (AREA)
- Inorganic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Combustion & Propulsion (AREA)
- Dispersion Chemistry (AREA)
- Curing Cements, Concrete, And Artificial Stone (AREA)
Abstract
The application relates to the field of low-carbon production of concrete, and particularly discloses low-carbon concrete and a preparation method thereof. The low-carbon concrete comprises the following raw materials in parts by weight: the modified fine aggregate is prepared by alkali-exciting regenerated micro powder, treating the activated regenerated micro powder by gamma-PGA polyglutamic acid and a silane coupling agent, and mixing the treated regenerated micro powder with natural sand stone, waste rubber particles and slag powder; the preparation method comprises the following steps: s1, weighing water, cement, recycled coarse aggregate and recycled fine aggregate according to the mass parts, and uniformly stirring; s2, adding silicon powder, metakaolin and fly ash into the stirred mixture, adding water and stirring uniformly; and S3, adding the glass fiber and the modified fine aggregate to obtain the low-carbon concrete. The low-carbon concrete can be used for reducing the using amount of cement and improving the compressive strength of the concrete; in addition, the preparation method has the advantages of simplicity and easiness in operation.
Description
Technical Field
The application relates to the field of low-carbon production of concrete, in particular to low-carbon concrete and a preparation method thereof.
Background
The low-carbon concrete technology refers to the related concrete technology capable of directly or indirectly reducing the gas emission of a greenhouse in the production and use processes of concrete. The method specifically comprises the following steps: the technology pursues the green high-performance concrete with long service life and high durability of the cement concrete on the premise of reducing the using amount of the cement in the concrete; reducing the carbon emissions in concrete applications has the most immediate effect of reducing the amount of cement used in the concrete.
Therefore, the selection of the composite cementitious material system with low cement dosage and large mineral admixture content in the concrete production process is an important technical principle. However, it is a subject of research in the art to obtain concrete with higher compressive strength while reducing the amount of cement used.
Disclosure of Invention
In order to reduce the using amount of cement and improve the compressive strength of concrete, the application provides the low-carbon concrete and the preparation method thereof.
In a first aspect, the present application provides a low carbon concrete, which adopts the following technical scheme:
the low-carbon concrete comprises the following raw materials in parts by weight: 150-200 parts of cement, 50-150 parts of recycled coarse aggregate, 115-150 parts of recycled fine aggregate, 421-569 parts of water, 45-55 parts of silica powder, 51-68 parts of metakaolin, 106-210 parts of fly ash, 50-85 parts of glass fiber and 155-245 parts of modified fine aggregate; the modified fine aggregate is prepared by treating the regenerated micro powder with gamma-PGA polyglutamic acid and a silane coupling agent after alkali excitation, and mixing the treated regenerated micro powder with natural sandstone, waste rubber particles and slag powder.
By adopting the technical scheme, the recycled aggregate is prepared by crushing, cleaning and grading waste concrete blocks, mixing the crushed, cleaned and graded concrete blocks with grading according to a certain proportion, partially or completely replacing natural aggregates such as sand stones and the like, replacing coarse aggregate in concrete with the recycled coarse aggregate, increasing the dynamic compressive property of the recycled aggregate compared with untreated recycled aggregate after the recycled aggregate is subjected to slurry coating treatment by cement slurry, improving the substitution rate, reducing the addition amount of cement, replacing the cement with the recycled coarse aggregate and the recycled fine aggregate, improving the water-cement ratio of the concrete, further reducing the cost of the concrete, recycling building waste, solving the problem of building waste, reducing the requirement on natural sand, mainly having pores of 3.5-4nm in the recycled concrete, reducing the total pore volume of the recycled concrete due to the addition of metakaolin, and improving the structural compactness of the recycled concrete due to the refinement of internal pores. The metakaolin is doped to improve the strength of the recycled concrete with different substitution rates, the metakaolin can be used for filling micropores and microcracks of the recycled aggregate, improving the contact surface of new and old mortar, and can also be used for filling micropores inside the new mortar, so that the compressive strength of the recycled concrete exceeds that of common concrete, and because the silica powder has the physical and chemical characteristics of small particle size, large specific area, high purity of active SiO2, high activity of strong-fire mountain ash and the like, the silica powder is used as an admixture and added into the concrete to improve the performance of the concrete in various aspects, and the glass fiber can improve the high-temperature performance of the concrete, because: the glass fiber has good heat resistance, the melting point of the glass fiber is high, the glass fiber can still keep the original shape after being subjected to high temperature of 600 ℃, the thermal expansion coefficient is low, the glass fiber is doped into the glass fiber, the generation of cracks in concrete at high temperature can be reduced to a certain extent, and the compressive strength of the concrete is improved.
Preferably, the feed comprises the following raw materials in parts by weight: the feed comprises the following raw materials in parts by weight: 145 parts of cement, 128 parts of recycled coarse aggregate, 123 parts of recycled fine aggregate, 489 parts of water, 49 parts of silica powder, 62 parts of metakaolin, 187 parts of fly ash, 68 parts of glass fiber and 198 parts of modified fine aggregate.
By adopting the technical scheme, the proportion of cement in concrete is reduced, the fly ash is used as a substitute material of the cement, the fly ash is used for substituting the cement to be added into the concrete, the fly ash is cheap and low in cost, the workability, the flowability and the durability of the concrete can be improved, the fly ash can be used as a waste resource, the effects of protecting the environment and saving energy and reducing emission are achieved, metakaolin is a metastable amorphous silicon-aluminum compound, and the silicon-aluminum compound is depolymerized to repolymerized under the alkali excitation of sodium hydroxide to form an aluminosilicate network structure. When the metakaolin is doped into concrete, the active alumina and the silicon oxide thereof quickly react with calcium hydroxide generated by cement hydration to promote the cement hydration reaction, thereby improving the compressive strength of the concrete. The modified fine aggregate is mainly used for improving the water-cement ratio in concrete, and is doped with admixture such as fly ash, metakaolin, silica powder and the like to pretreat recycled aggregate, fill pores to enhance compactness and improve the properties of recycled concrete.
Preferably, the modified fine aggregate comprises the following substances in parts by weight: 50-86 parts of natural sand, 24-36 parts of silane coupling agent, 84-125 parts of alkali-activated regenerated micro powder, 102-145 parts of waste rubber particles, 15-32 parts of gamma-PGA polyglutamic acid, 20-55 parts of sodium hydroxide and 64-95 parts of slag powder.
By adopting the technical scheme, the rubber has the characteristics of better toughness and the like, the rubber particles are doped into the concrete to fill the concrete gaps, the anti-cracking and pressure-resistant performance of the concrete can be improved, the waste rubber can be recycled, the pollution of the waste rubber to the environment is reduced, the rubber substitution rate is improved, the slump expansion of a concrete mixture is reduced compared with the reference mixing ratio, the compression strength of the concrete is improved, the regenerated micro powder refers to fine particles with the particle size of less than 0.16mm generated in the crushing process when the waste concrete is recycled and reformed, the regenerated micro powder has a promoting effect on the strength of the concrete under the condition of low water-cement ratio and shows certain activity, and the regenerated micro powder can form high polymer molecules after the alkali-excited regenerated fly ash is treated by the silane coupling agent and the gamma-PGA polyglutamic acid, the high polymer molecules have certain viscosity, so that the compression strength of the fine aggregate is improved, and the later strength development of the concrete can also have advantages.
Preferably, the step of modifying the modified fine aggregate comprises:
(1) Pretreating waste rubber particles, namely soaking the waste rubber particles for 12 hours by using a 25% sodium hydroxide solution to obtain pretreated high-performance rubber particles;
(2) Uniformly mixing and grinding the alkali-excited regenerated micro powder, wherein the alkali-excited regenerated micro powder comprises calcium hydroxide and sodium silicate, and the alkali-excited regenerated micro powder is prepared by taking 64-96 parts of regenerated micro powder as a raw material and 9-13 parts of alkali-excited agent for 20 min;
(3) Adding a silane coupling agent into the alkali-activated regenerated micro powder, uniformly stirring, adding gamma-PGA polyglutamic acid, and continuously stirring to prepare pretreated regenerated micro powder;
(4) Mixing natural sandstone, pretreated recycled micropowder, high-performance rubber and slag powder, and uniformly mixing to obtain the modified fine aggregate.
Through adopting above-mentioned technical scheme, carry out modification treatment to rubber with 25% concentration's sodium hydroxide solution, the rubber particle surface after the processing becomes more crude, and a large amount of little holes appear, can adsorb little fine aggregate granule in these little holes for whole more stable, and then improved the compressive strength of concrete, the compressive strength reduction range of the concrete of rubber particle diameter relatively great is less than the concrete that rubber particle diameter is less. The regenerated micropowder is excited by using an alkaline activator calcium hydroxide and sodium silicate, and the excitation mechanism of the alkaline activator is mainly to increase the OH-concentration of slurry. Under the action of alkaline environment, free unsaturated active bonds are more easily formed on the surfaces of the building rubbish powder particles. The reaction reduces the polymerization degree of network polymers formed by the alumina and the silicon oxide on the surface of the construction waste, and the network polymers are easier to react with active components in a system liquid phase, so that the generation amounts of gelling products, hydrated calcium silicate, hydrated aluminum silicate and the like are increased, and the effect of activating the gelling activity of construction waste powder is finally achieved. The silane coupling agent and the gamma-PGA polyglutamic acid are added into the alkali-activated regenerated micro powder, so that the regenerated micro powder and the gamma-PGA polyglutamic acid are combined together through the silane coupling agent to form a macromolecular polymer, the viscosity of fine aggregate is enhanced, the gamma-PGA polyglutamic acid is a main component forming natto viscous colloid and has the effect of promoting mineral substance absorption, the carboxyl group of the gamma-PGA polyglutamic acid can be combined with the silane coupling agent, the gamma-PGA polyglutamic acid and the regenerated micro powder can be combined through the silane coupling agent to form a high polymer with the adsorption performance, and the compressive strength of concrete is further improved.
Preferably, the particle size of the regenerated micro powder is 5-160um.
By adopting the technical scheme, the physical excitation of the regenerated micro powder is controlled by controlling the particle size, the larger the fineness of the regenerated micro powder is, the larger the potential activity of the regenerated micro powder is, the effect of exciting the activity of the regenerated micro powder is achieved, the breaking strength of the concrete is improved, and the compressive strength is further improved.
Preferably, the particle size of the waste rubber particles is 0.8-2.2mm.
By adopting the technical scheme, the rubber particles have the characteristics of hydrophobicity and the like, can block the water seepage channel in the concrete, the compressive strength of the concrete with the relatively larger rubber particle size is reduced by a range smaller than that of the concrete with the smaller rubber particle size, and the smaller the rubber particles are, the more obviously the compressive strength of the concrete is improved by the rubber mixed in the concrete.
Preferably, the concrete raw material also comprises 25-48 parts by weight of an additive, and the additive is a shrinkage reducing agent.
By adopting the technical scheme, the addition of the shrinkage reducing agent improves the later-period mechanical property and creep property of the recycled aggregate concrete. Compared with the reference concrete prepared from natural coarse aggregate, the concrete prepared from the shrinkage reducing agent and the concrete prepared from high-quality regenerated coarse aggregate have higher compressive strength, elastic modulus and lower creep, and the compressive strength of the concrete is improved.
In a second aspect, the present application provides a method for preparing a low-carbon concrete, which adopts the following technical scheme:
the preparation method of the low-carbon concrete comprises the following steps:
s1, weighing water, cement, recycled coarse aggregate and recycled fine aggregate according to the mass parts, mixing and stirring, and stirring uniformly;
s2, adding silicon powder, metakaolin and fly ash into the stirred mixture, continuously stirring, adding water and uniformly stirring;
and S3, adding the glass fiber and the modified fine aggregate, and continuously stirring to obtain the low-carbon concrete.
By adopting the technical scheme, the recycled coarse aggregate is obtained after the concrete is crushed and screened, the coarse aggregate is used for completely replacing the coarse aggregate in the cement stabilized macadam, and researches show that the concrete prepared by using the recycled coarse aggregate is firstly mixed with the cement, the recycled coarse aggregate and the recycled fine aggregate along with the increase of the water-cement ratio, so that the proper amount of the recycled coarse aggregate is doped to have a certain reinforcing effect on the compressive strength of the concrete. Along with the increase of the substitution rate of the recycled coarse aggregate, the change of the compressive strength of the concrete shows a rule of increasing firstly and then reducing. The overall performance of the relative compressive strength of the recycled concrete after high temperature is better than that of the common concrete, and then silicon powder, metakaolin and fly ash are added, so that the concrete can be regarded as a continuous graded particle accumulation system, gaps of coarse aggregates are filled by fine aggregates, gaps of fine aggregates are filled by cement particles, and gaps among the cement particles are filled by finer particles. Finely ground metakaolin can act as such fine particles in concrete. On the other hand, the hydration reaction generates hydrated calcium silicate and hydrated calcium sulfoaluminate with filling effect, optimizes the internal pore structure of the concrete, reduces the porosity and the pore diameter, and leads the concrete to form a compact filling structure and a self-compact stacking system with microscopic layers, thereby effectively improving the mechanical property and the durability of the concrete. The glass fiber is added, so that the concrete is improved to a certain extent, and the compressive strength of the concrete is improved.
Preferably, the concrete also comprises 25-48 parts by weight of shrinkage reducing agent, and the shrinkage reducing agent is added into the S3 and uniformly stirred to prepare the low-carbon concrete.
By adopting the technical scheme, the shrinkage-reducing agent is an additive capable of reducing the early shrinkage of concrete. The main action mechanism is to reduce the surface tension of pore water to reduce the shrinkage stress generated when capillary pores are dehydrated, on the other hand, the viscosity of the pore water in concrete is increased, the adsorption of water in concrete colloid is enhanced to reduce the shrinkage value of the concrete, the mixing of the shrinkage reducing agent reduces the surface tension of the solution and also reduces the evaporation rate of the solution, the action mechanism of the shrinkage reducing agent not only reduces the surface tension of the pore solution, but also can reduce the shrinkage of a cement-based material by reducing the evaporation of the pore solution, and further improves the compressive strength of the concrete.
In summary, the present application has the following beneficial effects:
1. as the fly ash is used as a substitute material of cement, the metakaolin is doped into the concrete, the active alumina and the silicon oxide rapidly react with the calcium hydroxide generated by cement hydration to promote the hydration reaction of the cement, so that the compressive strength of the concrete is improved, the admixture such as the fly ash, the metakaolin, the silicon powder and the like is doped to carry out pretreatment on the recycled aggregate, the filling pores are filled to enhance the compactness, and the properties of the recycled concrete can be improved.
2. The preferred adoption alkali arouses regeneration miropowder and abandonment rubber granule modified fine aggregate among this application for it has the effect of filling the concrete space to mix the rubber granule in the concrete, can improve the anti-crack and the compressive strength performance of concrete, regeneration miropowder has the promotion effect to the intensity of concrete, show certain activity, regeneration miropowder passes through silane coupling agent and gamma-PGA polyglutamic acid, form macromolecular polymer, make the viscidity reinforcing of fine aggregate, also can have the advantage to the intensity development in concrete later stage.
3. According to the method, cement, the recycled coarse aggregate and the recycled fine aggregate are mixed firstly, then a proper amount of recycled coarse aggregate is doped to achieve a certain reinforcing effect on the compressive strength of concrete, then silicon powder, metakaolin and fly ash are added, the concrete can be regarded as a continuous graded particle accumulation system, gaps of the coarse aggregate are filled with the fine aggregate, gaps of the fine aggregate are filled with cement particles, gaps among the cement particles are filled with finer particles, the glass fiber is doped to achieve a certain improvement effect on the concrete, and the compressive strength of the concrete is improved.
Detailed Description
The following examples, which are specifically illustrated below, further illustrate the present invention: the following examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer, and the starting materials used in the following examples are available from ordinary commercial sources unless otherwise specified.
The cement is PI42.5 type cement; the shrinkage reducing agent is SBT-SRA, yellow liquid and alkyl polyether as main component; the silane coupling agent is 211519-85-6 silane coupling agent.
Examples of preparation of starting materials and/or intermediates
Preparation example 1
The modified fine aggregate comprises the following substances in parts by mass: 50kg of natural sandstone, 24kg of silane coupling agent, 84kg of alkali-activated regenerated micro powder, 102kg of waste rubber particles, 15kg of gamma-PGA polyglutamic acid, 20kg of sodium hydroxide and 64kg of slag powder.
The modification step of the modified fine aggregate comprises the following steps:
(1) Pretreating waste rubber particles, namely soaking the waste rubber particles in a 25% sodium hydroxide solution for 12 hours to obtain pretreated rubber particles;
(2) The alkali-activated regenerated micro powder is prepared by uniformly mixing 64kg of regenerated micro powder as a raw material with 9kg of alkali activator, putting the mixture into a centrifugal pulverizer, and grinding the mixture for 20min, wherein the alkali activator comprises calcium hydroxide and sodium silicate, the mass ratio of the calcium hydroxide to the sodium silicate is 0.7;
(3) Adding a silane coupling agent into the alkali-activated regenerated micro powder, uniformly stirring, adding gamma-PGA polyglutamic acid, and continuously stirring to prepare pretreated regenerated micro powder;
(4) Mixing the natural sand and stone, the pretreated recycled micro powder, the high-performance rubber and the slag powder, and uniformly mixing to prepare the modified fine aggregate.
Preparation example 2
The modified fine aggregate comprises the following substances in parts by mass: 65kg of natural sandstone, 29kg of silane coupling agent, 108kg of alkali-activated regenerated micro powder, 128kg of waste rubber particles, 21kg of gamma-PGA polyglutamic acid, 35kg of sodium hydroxide and 88kg of slag powder.
The modification step of the modified fine aggregate comprises the following steps:
(1) Pretreating waste rubber particles, namely soaking the waste rubber particles in a 25% sodium hydroxide solution for 12 hours to obtain pretreated rubber particles;
(2) The method comprises the following steps of (1) carrying out alkali excitation on regenerated micro powder, wherein an alkali activator comprises calcium hydroxide and sodium silicate, the mass ratio of the calcium hydroxide to the sodium silicate is 0.7, uniformly mixing 85kg of the regenerated micro powder with 11kg of the alkali activator, putting the mixture into a centrifugal pulverizer, and grinding the mixture for 20min to obtain the alkali-excited regenerated micro powder;
(3) Adding a silane coupling agent into the alkali-activated regenerated micro powder, uniformly stirring, adding gamma-PGA polyglutamic acid, and continuously stirring to prepare pretreated regenerated micro powder;
(4) Mixing natural sandstone, pretreated recycled micropowder, high-performance rubber and slag powder, and uniformly mixing to obtain the modified fine aggregate.
Preparation example 3
The modified fine aggregate comprises the following substances in parts by mass: 86kg of natural sand, 29kg of silane coupling agent, 125kg of alkali-activated regenerated micro powder, 145kg of waste rubber particles, 32kg of gamma-PGA polyglutamic acid, 55kg of sodium hydroxide and 95kg of slag powder.
The modification step of the modified fine aggregate comprises the following steps:
(1) Pretreating waste rubber particles, namely soaking the waste rubber particles in a 25% sodium hydroxide solution for 12 hours to obtain pretreated rubber particles;
(2) The method comprises the following steps of (1) carrying out alkali excitation on regenerated micro powder, wherein an alkali activator comprises calcium hydroxide and sodium silicate, the mass ratio of the calcium hydroxide to the sodium silicate is 0.7, uniformly mixing 96kg of the regenerated micro powder with 13kg of the alkali activator, putting the mixture into a centrifugal pulverizer, and grinding the mixture for 20min to obtain the alkali-excited regenerated micro powder;
(3) Adding a silane coupling agent into the alkali-activated regenerated micro powder, uniformly stirring, adding gamma-PGA polyglutamic acid, and continuously stirring to prepare pretreated regenerated micro powder;
(4) Mixing natural sandstone, pretreated recycled micropowder, high-performance rubber and slag powder, and uniformly mixing to obtain the modified fine aggregate.
Examples
Example 1
The preparation method of the low-carbon concrete comprises the following steps:
s1, 421kg of water, 150kg of cement, 50kg of recycled coarse aggregate and 115kg of recycled fine aggregate are weighed according to the mass parts, mixed and stirred, and uniformly stirred;
s2, adding 45kg of silicon powder, 51kg of metakaolin and 106kg of fly ash into the stirred mixture, continuously stirring, adding water and uniformly stirring;
s3, respectively adding 50kg of glass fiber and 155kg of the modified fine aggregate prepared in the preparation example 3, and continuously stirring to obtain the low-carbon concrete.
Example 2
The preparation method of the low-carbon concrete comprises the following steps:
s1, weighing 485kg of water, 170kg of cement, 88kg of recycled coarse aggregate and 128kg of recycled fine aggregate according to parts by mass, mixing and stirring uniformly;
s2, adding 45kg of silicon powder, 55kg of metakaolin and 156kg of fly ash into the stirred mixture, continuously stirring, adding water and uniformly stirring;
s3, respectively adding 68kg of glass fiber and 179kg of the modified fine aggregate prepared in the preparation example 3, and continuously stirring to obtain the low-carbon concrete.
Example 3
A preparation method of low-carbon concrete comprises the following steps:
s1, weighing 569kg of water, 200kg of cement, 150kg of recycled coarse aggregate and 150kg of recycled fine aggregate according to the mass parts, mixing and stirring uniformly;
s2, adding 55kg of silicon powder, 68kg of metakaolin and 210kg of fly ash into the stirred mixture, continuously stirring, adding water and uniformly stirring;
s3, adding 85kg of glass fiber and 245kg of the modified fine aggregate prepared in the preparation example 3 respectively, and continuously stirring to obtain the low-carbon concrete.
Example 4
The preparation method of the low-carbon concrete comprises the steps of adding a shrinkage reducing agent into S3, adding 48kg of the shrinkage reducing agent, and uniformly stirring to obtain the low-carbon concrete.
Comparative example
Comparative example 1
The low-carbon concrete is different from the low-carbon concrete in example 4 in that: the low-carbon concrete is not added with modified fine aggregate.
Comparative example 2
The low-carbon concrete is different from the low-carbon concrete in example 4 in that: the modified fine aggregate in the low-carbon concrete is replaced by the fine aggregate.
Comparative example 3
The low-carbon concrete is different from the low-carbon concrete in example 4 in that: the low-carbon concrete is not added with glass fiber.
Comparative example 4
The low-carbon concrete is different from the low-carbon concrete in example 4 in that: the glass fiber in the low-carbon concrete is replaced by steel fiber.
Comparative example 5
The low-carbon concrete is different from the low-carbon concrete in example 4 in that: metakaolin is not added into the low-carbon concrete.
Comparative example 6
The low-carbon concrete is different from the low-carbon concrete in example 4 in that: the addition amount of the cement in the low-carbon concrete is 360kg.
Comparative example 7
The low-carbon concrete is different from the low-carbon concrete in example 4 in that: fly ash is not added into the low-carbon concrete.
Comparative example 8
The low-carbon concrete is different from the low-carbon concrete in example 4 in that: the recycled coarse aggregate in the low-carbon concrete is replaced by coarse aggregate.
Performance test
The low carbon concretes prepared in examples 1 to 4 and comparative examples 1 to 8 were subjected to performance tests.
The detection standard is GB/T50082-2009 Standard test methods for the long-term performance and the durability of common concrete; GB/T50081-2019 Standard of concrete physical and mechanical property test method.
Detection method/test method
TABLE 1
As can be seen from table 1, the invention.
It can be seen from the combination of examples 1 to 4 and comparative examples 1 to 8 and the combination of table 1 that the 3d flexural strength, the 3d compressive strength, the 7d flexural strength, the 7d compressive strength, the 28d flexural strength and the 28d compressive strength of example 4 are all higher, which indicates that the silica powder, the metakaolin, the fly ash, the glass fiber and the modified fine aggregate in the concrete can simultaneously improve the compressive strength and the flexural strength of the concrete, wherein the addition of the modified fine aggregate improves the water-cement ratio of the concrete, further achieves the effect of activating the gelling activity of the construction waste powder, and further improves the compressive strength and the flexural strength of the concrete.
The detection results of the comparative example 1 and the comparative example 2 are combined, so that the compressive strength and the flexural strength of the concrete are affected by adding no modified fine aggregate or adding common fine aggregate, and the water-cement ratio of the modified fine aggregate is improved, so that the polymerization degree of a network polymer formed in the concrete is reduced, and the network polymer is easier to react with an active component in a system liquid phase, a cementitious product is improved, and the compressive strength and the flexural strength are improved.
By combining the detection results of the comparative examples 3 and 4, it can be seen that the addition of the glass fiber into the concrete can reduce the generation of cracks in the concrete at high temperature to a certain extent when the glass fiber is doped, delay the heat conduction of the concrete and further improve the compressive strength of the concrete.
According to the detection results of the comparative example 5 and the comparative example 6, the metakaolin is not added into the concrete, the content of the cement is increased, the compressive strength of the concrete cannot be improved, the total pore volume of the recycled concrete is reduced due to the metakaolin, the structural compactness of the recycled concrete is improved due to the refinement of internal pores, the concrete carbonization speed is influenced due to the increase of the cement content, and the durability of the concrete is reduced.
Combining the detection results of comparative example 5 and comparative example 6, it can be seen that the compressive strength of the concrete cannot be improved because no fly ash is added to the concrete or the recycled coarse aggregate is replaced by the common coarse aggregate, and the fly ash can improve the workability, fluidity and durability of the concrete.
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 (9)
1. The low-carbon concrete is characterized by comprising the following raw materials in parts by weight: 150-200 parts of cement, 50-150 parts of recycled coarse aggregate, 115-150 parts of recycled fine aggregate, 421-569 parts of water, 45-55 parts of silica powder, 51-68 parts of metakaolin, 106-210 parts of fly ash, 50-85 parts of glass fiber and 155-245 parts of modified fine aggregate; the modified fine aggregate is prepared by treating the regenerated micro powder with gamma-PGA polyglutamic acid and a silane coupling agent after alkali excitation, and mixing the treated product with natural sandstone, waste rubber particles and slag powder.
2. The low carbon concrete of claim 1, wherein: the feed comprises the following raw materials in parts by weight: 145 parts of cement, 128 parts of recycled coarse aggregate, 123 parts of recycled fine aggregate, 489 parts of water, 49 parts of silica powder, 62 parts of metakaolin, 187 parts of fly ash, 68 parts of glass fiber and 198 parts of modified fine aggregate.
3. The low carbon concrete of claim 1, wherein: the modified fine aggregate comprises the following substances in parts by weight: 50-86 parts of natural sand, 24-36 parts of silane coupling agent, 84-125 parts of alkali-activated regenerated micro powder, 102-145 parts of waste rubber particles, 15-32 parts of gamma-PGA polyglutamic acid, 20-55 parts of sodium hydroxide and 64-95 parts of slag powder.
4. The low carbon concrete of claim 3, wherein: the modification step of the modified fine aggregate comprises the following steps:
(1) Pretreating the waste rubber particles, soaking the waste rubber particles in a 25% sodium hydroxide solution for 12 hours to obtain pretreated high-performance rubber particles;
(2) Uniformly mixing and grinding the alkali-excited regenerated micro powder, wherein the alkali-excited regenerated micro powder comprises calcium hydroxide and sodium silicate, and the alkali-excited regenerated micro powder is prepared by taking 64-96 parts of regenerated micro powder as a raw material and 9-13 parts of alkali-excited agent for 20 min;
(3) Adding a silane coupling agent into the alkali-activated regenerated micro powder, uniformly stirring, adding gamma-PGA polyglutamic acid, and continuously stirring to prepare pretreated regenerated micro powder;
(4) Mixing natural sandstone, pretreated recycled micropowder, high-performance rubber and slag powder, and uniformly mixing to obtain the modified fine aggregate.
5. The low carbon concrete of claim 3, wherein: the particle size of the regenerated micro powder is 5-160um.
6. The low carbon concrete of claim 3, wherein: the particle size of the waste rubber particles is 0.8-2.2mm.
7. The low-carbon concrete according to claim 1, wherein: the concrete also comprises 25-48 parts by weight of an additive which is a shrinkage reducing agent.
8. The method for preparing the low-carbon concrete according to claim 1, wherein the method comprises the following steps: the method comprises the following steps:
s1, weighing water, cement, recycled coarse aggregate and recycled fine aggregate according to the mass parts, mixing and stirring, and stirring uniformly;
s2, adding silicon powder, metakaolin and fly ash into the stirred mixture, continuously stirring, adding water and uniformly stirring;
and S3, adding the glass fiber and the modified fine aggregate, and continuously stirring to obtain the low-carbon concrete.
9. The preparation method of the low-carbon concrete according to claim 8, characterized by comprising the following steps: the concrete also comprises 25-48 parts by weight of shrinkage reducing agent, wherein the shrinkage reducing agent is added into the S3 and is uniformly stirred to prepare the low-carbon concrete.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211148726.0A CN115417642B (en) | 2022-09-21 | 2022-09-21 | Low-carbon concrete and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211148726.0A CN115417642B (en) | 2022-09-21 | 2022-09-21 | Low-carbon concrete and preparation method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN115417642A true CN115417642A (en) | 2022-12-02 |
| CN115417642B CN115417642B (en) | 2023-06-30 |
Family
ID=84203513
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202211148726.0A Active CN115417642B (en) | 2022-09-21 | 2022-09-21 | Low-carbon concrete and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115417642B (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116496050A (en) * | 2023-05-13 | 2023-07-28 | 广州市建筑集团混凝土有限公司 | High-strength recycled concrete for bearing mechanism and preparation method thereof |
| CN116535168A (en) * | 2023-05-24 | 2023-08-04 | 中建西部建设北方有限公司 | Low-carbon concrete and preparation method thereof |
| CN116947531A (en) * | 2023-07-13 | 2023-10-27 | 广西建宏水泥制品有限公司 | High-strength corrosion-resistant light foam concrete for backfilling of submerged toilet |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20080029059A (en) * | 2006-09-28 | 2008-04-03 | 한국화학연구원 | High-strength calcium phosphate cements |
| CN104788054A (en) * | 2015-04-10 | 2015-07-22 | 浙江大学宁波理工学院 | Eco-friendly self-compacting concrete prepared through complete recycling of waste concrete |
| CN110550914A (en) * | 2019-10-14 | 2019-12-10 | 上海浦盈混凝土有限公司 | high-strength concrete and preparation method thereof |
| CN111170697A (en) * | 2020-01-20 | 2020-05-19 | 中建商品混凝土有限公司 | Modified rubber particle light-weight ultrahigh-performance concrete and preparation method thereof |
| CN112851250A (en) * | 2021-01-29 | 2021-05-28 | 西安工业大学 | High-strength recycled concrete and preparation method and application thereof |
-
2022
- 2022-09-21 CN CN202211148726.0A patent/CN115417642B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20080029059A (en) * | 2006-09-28 | 2008-04-03 | 한국화학연구원 | High-strength calcium phosphate cements |
| CN104788054A (en) * | 2015-04-10 | 2015-07-22 | 浙江大学宁波理工学院 | Eco-friendly self-compacting concrete prepared through complete recycling of waste concrete |
| CN110550914A (en) * | 2019-10-14 | 2019-12-10 | 上海浦盈混凝土有限公司 | high-strength concrete and preparation method thereof |
| CN111170697A (en) * | 2020-01-20 | 2020-05-19 | 中建商品混凝土有限公司 | Modified rubber particle light-weight ultrahigh-performance concrete and preparation method thereof |
| CN112851250A (en) * | 2021-01-29 | 2021-05-28 | 西安工业大学 | High-strength recycled concrete and preparation method and application thereof |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116496050A (en) * | 2023-05-13 | 2023-07-28 | 广州市建筑集团混凝土有限公司 | High-strength recycled concrete for bearing mechanism and preparation method thereof |
| CN116535168A (en) * | 2023-05-24 | 2023-08-04 | 中建西部建设北方有限公司 | Low-carbon concrete and preparation method thereof |
| CN116535168B (en) * | 2023-05-24 | 2024-05-10 | 中建西部建设北方有限公司 | Low-carbon concrete and preparation method thereof |
| CN116947531A (en) * | 2023-07-13 | 2023-10-27 | 广西建宏水泥制品有限公司 | High-strength corrosion-resistant light foam concrete for backfilling of submerged toilet |
Also Published As
| Publication number | Publication date |
|---|---|
| CN115417642B (en) | 2023-06-30 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN115417642B (en) | Low-carbon concrete and preparation method thereof | |
| Tahwia et al. | Enhancing sustainability of ultra-high performance concrete utilizing high-volume waste glass powder | |
| RU2599742C2 (en) | Geopolymer composite for ultra-high quality concrete | |
| CN112125584B (en) | Preparation method of low-hydration-heat green self-leveling concrete | |
| CN109336456B (en) | Red mud-based asphalt mixture warm-mixing agent and preparation method thereof | |
| KR101410056B1 (en) | A Concrete Using Non-sintering Binder Having Bottom Ash | |
| Dheyaaldin et al. | The effects of nanomaterials on the characteristics of aluminosilicate-based geopolymer composites: a critical review | |
| CN111875300B (en) | Novel fine concrete based on green geopolymer and dredged sand and preparation method thereof | |
| CN113277790A (en) | Slag-based highway grouting material and preparation method thereof | |
| CN115124317B (en) | Composite activated regenerated micro-powder concrete based on slurry wrapping process and preparation method thereof | |
| Guo et al. | Sodium-based activators in alkali-activated materials: Classification and comparison | |
| Tammam et al. | Effect of waste filler materials and recycled waste aggregates on the production of geopolymer composites | |
| CN111253130A (en) | High-strength heat-resistant self-repairing concrete and preparation method thereof | |
| Yu et al. | Microstructure and mechanical performance of alkali-activated tuff-based binders | |
| KR101018009B1 (en) | Manufacturing method of cement zero concrete using mixed waste glass powder and fly ash as binder | |
| CN104386954A (en) | Silicon carbide waste reinforced wear-resistant floor mortar and its preparation method | |
| CN113501691A (en) | High-strength nano silicon dioxide recycled concrete and preparation method thereof | |
| Xie et al. | Effects of pretreated recycled fine aggregates on the mechanical properties and microstructure of alkali-activated mortar | |
| Li et al. | Properties and microstructure development of alkali-activated coal bottom ash and titanium-extraction tailing slag binder | |
| CN116161929B (en) | Recycled concrete and preparation method thereof | |
| CN112408875A (en) | Regenerated geopolymer mortar and preparation method and application thereof | |
| CN111978963A (en) | Soil solidifying composition, preparation method and application thereof | |
| Alok et al. | Strength studies on geopolymer concrete produced by recycled coarse aggregate and quarry stone dust as fine aggregate | |
| Yang et al. | Carbonation mechanism and cementation properties of recycled cement paste based on CO2 injection time and pressure | |
| CN113248191B (en) | Inert concrete waste slurry solidified material and preparation method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |