CN112408926A - Anti-cracking recycled concrete and preparation method thereof - Google Patents

Anti-cracking recycled concrete and preparation method thereof Download PDF

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CN112408926A
CN112408926A CN202011347797.4A CN202011347797A CN112408926A CN 112408926 A CN112408926 A CN 112408926A CN 202011347797 A CN202011347797 A CN 202011347797A CN 112408926 A CN112408926 A CN 112408926A
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parts
deionized water
stirring
preparation
concrete
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彭材大
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Guangzhou Zhicheng Building Materials Technology Co ltd
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Guangzhou Zhicheng Building Materials Technology Co ltd
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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
    • C04B28/08—Slag 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
    • C04B14/36—Inorganic materials not provided for in groups C04B14/022 and C04B14/04 - C04B14/34
    • 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
    • C04B20/00—Use of materials as fillers for mortars, concrete or artificial stone according to more than one of groups C04B14/00 - C04B18/00 and characterised by shape or grain distribution; Treatment of materials according to more than one of the groups C04B14/00 - C04B18/00 specially adapted to enhance their filling properties in mortars, concrete or artificial stone; Expanding or defibrillating materials
    • C04B20/02—Treatment
    • C04B20/023—Chemical treatment
    • 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
    • C04B7/00—Hydraulic cements
    • C04B7/12—Natural pozzuolanas; Natural pozzuolana cements; Artificial pozzuolanas or artificial pozzuolana cements other than those obtained from waste or combustion residues, e.g. burned clay; Treating inorganic materials to improve their pozzuolanic characteristics
    • C04B7/13—Mixtures thereof with inorganic cementitious materials, e.g. 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
    • C04B7/00—Hydraulic cements
    • C04B7/14—Cements containing slag
    • C04B7/147—Metallurgical slag
    • C04B7/153—Mixtures thereof with other inorganic cementitious materials or other activators
    • C04B7/17—Mixtures thereof with other inorganic cementitious materials or other activators with calcium oxide containing activators
    • C04B7/19—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
    • C04B7/00—Hydraulic cements
    • C04B7/36—Manufacture of hydraulic cements in general
    • 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
    • C04B2111/2038—Resistance against physical degradation
    • 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
    • C04B2111/34—Non-shrinking or non-cracking materials
    • C04B2111/343—Crack resistant materials
    • 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
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P40/00—Technologies relating to the processing of minerals
    • Y02P40/10—Production of cement, e.g. improving or optimising the production methods; Cement grinding

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Ceramic Engineering (AREA)
  • Materials Engineering (AREA)
  • Structural Engineering (AREA)
  • Organic Chemistry (AREA)
  • Inorganic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Civil Engineering (AREA)
  • Curing Cements, Concrete, And Artificial Stone (AREA)

Abstract

The invention belongs to the technical field of concrete, and particularly relates to anti-cracking recycled concrete and a preparation method thereof; according to the invention, the metakaolin is subjected to intercalation modification by adopting the hydrophobic silica aerogel, the micromolecular hydrophobic silica aerogel is inserted between the layered structures of the metakaolin, the interlayer spacing of the metakaolin is increased, the modified metakaolin is prepared by utilizing the light, porous and low heat-conducting properties of the silica aerogel and combining the high volcanic ash effect of the metakaolin, and the properties of compression resistance, bending resistance, crack resistance and the like of a concrete structure can be obviously improved by adding the modified metakaolin into concrete.

Description

Anti-cracking recycled concrete and preparation method thereof
Technical Field
The invention belongs to the technical field of concrete, and particularly relates to anti-cracking recycled concrete and a preparation method thereof.
Background
Because infrastructure construction is in a high-speed development stage, a great deal of concrete is used in dams in water conservancy and hydropower construction, roads, railways, bridges, wharfs, tunnels in traffic construction and civil construction projects. The concrete has shrinkage and cracking caused by shrinkage to different degrees, and the phenomenon of water seepage occurs, so that the corrosion of the surface and the inside of the concrete and the corrosion of reinforcing steel bars inside the concrete are caused, the durability of the concrete is influenced, and the service life of a concrete project is shortened. With the production of High Performance Concrete (HPC) and High Strength Concrete (HSC), the amount of cement in the concrete increases, the amount of water used decreases, and the amount of active admixtures increases, increasing the above-mentioned cracking levels.
At present, the expansion agent is generally used in the market as a shrinkage compensation material to improve the performance of concrete antibody volume deformation, but the concrete still has the phenomena of high hydration heat, large shrinkage deformation, cracking, leakage and the like after being used, and the strength is greatly reduced. Most of the concrete reinforcing shrinkage materials are subjected to high-temperature treatment by pure raw materials, so that huge energy consumption is caused, influence on the environment is brought to different degrees, and the product is high in production cost and high in market selling price. Therefore, for concrete construction, especially for bulky concrete, high strength concrete, look for a novel reinforcement shrink material, solve the problem of concrete deformation under the prerequisite that can guarantee the concrete strength, prevent the fracture and the seepage of concrete.
Disclosure of Invention
The invention aims to provide anti-cracking recycled concrete and a preparation method thereof.
The technical problems to be solved by the invention are as follows:
in the prior art, a swelling agent is generally used as a shrinkage compensation material to improve the performance of concrete antibody volume deformation, but the concrete still has the phenomena of high hydration heat, large shrinkage deformation, cracking, leakage and the like after being used, and the strength is greatly reduced. Most of the concrete reinforcing shrinkage materials are subjected to high-temperature treatment by pure raw materials, so that huge energy consumption is caused, influence on the environment is brought to different degrees, and the product is high in production cost and high in market selling price.
The purpose of the invention can be realized by the following technical scheme: the preparation method of the anti-cracking recycled concrete comprises the following steps:
firstly, preparing the following raw materials in parts by weight:
15-30 parts of composite volcanic ash portland cement, 10-15 parts of sea sand, 30-50 parts of pebbles, 30-50 parts of deionized water, 20-30 parts of hydrotalcite, 30-50 parts of modified metakaolin, 20-40 parts of fly ash, 10-15 parts of phosphogypsum, 2-5 parts of aluminum hydrogen phosphate, 2-4 parts of aluminum potassium sulfate, alpha-Al2O32-3 parts of nano powder, 0.1-1 part of sodium polyacrylate, 5-10 parts of basalt fiber, 1.5-2 parts of water reducing agent, 1.5-2 parts of CM-DPS deep penetration crystallization sealing waterproof agent, 10.5-14 parts of rubber emulsion and 3-4 parts of silane coupling agent;
secondly, hydrotalcite, modified metakaolin, fly ash, phosphogypsum, aluminium phosphate dibasic, aluminium potassium sulfate, sodium polyacrylate and alpha-Al2O3Adding the nano powder and the basalt fiber into a ball mill, and performing ball milling for 45-50min to prepare the concrete anti-cracking additive;
thirdly, mixing and stirring the composite pozzolan portland cement, the sea sand, the stones and the deionized water, and gradually adding 3 parts of CM-DPS deep penetration crystallization sealing waterproof agent, rubber emulsion and silane coupling agent in the stirring process; and mixing for 15-20min, adding the prepared concrete anti-cracking additive and the water reducing agent, and mixing for 20-25min to obtain the anti-cracking recycled concrete.
Preferably, the composite pozzolan portland cement is made by:
step A1, adding 10 parts of portland cement clinker, 2 parts of granulated blast furnace slag, 5 parts of limestone and 2 parts of pozzolan into a stirring barrel, stirring and mixing for 7-12min under the condition of the rotating speed of 75-110r/min, then adding 2 parts of deionized water into the stirring barrel under the condition of reducing the rotating speed to 40-55r/min, and stirring and mixing for 3-5min to obtain crude pozzolan portland cement;
and A2, adding 3mol/L sodium hydroxide into the pozzolan portland cement obtained in the step A1, adjusting the pH value to 7.5-8, continuously adding 1 part of deionized water, and stirring and mixing for 3-5min to obtain the composite pozzolan portland cement.
Preferably, the modified metakaolin is prepared by the following steps:
step S1, adding water glass and deionized water into a beaker according to the mass ratio of 1:4, stirring for 10-15min under the condition that the rotating speed is 150-;
s2, dropwise adding 1mol/L ammonia water solution into the silicic acid solution obtained in the step S1, stirring for 5min under the condition that the rotation speed is 100 plus 150r/min, sealing by a preservative film, aging for 24h at normal temperature to obtain water glass gel, filling the water glass gel into a sealing bag, grinding, transferring into a beaker, adding absolute ethyl alcohol, trimethylchlorosilane and n-hexane into the beaker, stirring for 30-60min under the condition that the rotation speed is 200 plus 300r/min, filtering, washing a filter cake for 3-5 times by deionized water, and finally drying for 4h at 40 ℃, 60 ℃, 80 ℃, 100 ℃ and 120 ℃ respectively under normal pressure to obtain hydrophobic silica aerogel;
step S3, adding hydrophobic silica aerogel, metakaolin and absolute ethyl alcohol into a beaker, ultrasonically dispersing for 20-40min under the condition of frequency of 30-50kHz, then aging for 22-24h under the condition of water bath at 40-50 ℃, then filtering, washing a filter cake for 3-5 times by using deionized water, and finally drying in an oven at 100-105 ℃ to constant weight to prepare the modified metakaolin.
Preferably, the volume ratio of the silicic acid solution, the 1mol/L ammonia water solution, the anhydrous ethanol, the trimethylchlorosilane and the n-hexane in the step S2 is 8:0.1-0.3:15:0.3-0.5: 0.3-0.5.
Preferably, the amount ratio of the hydrophobic silica aerogel, the metakaolin and the absolute ethyl alcohol in the step S3 is 1 g: 2-4 g: 5-10 mL.
One key technical point of the invention is that the specially modified metakaolin is added, firstly, a water glass solution is used as a raw material, modifier trimethylchlorosilane and normal hexane are added to prepare hydrophobic silica aerogel, then the hydrophobic silica aerogel is combined with the metakaolin, so that micromolecular hydrophobic silica aerogel is inserted between the layered structures of the metakaolin, the interlayer spacing of the metakaolin is increased, and the compression resistance, bending resistance, crack resistance and other properties of a concrete structure are obviously improved when the concrete additive is used by utilizing the light, porous and low heat conduction performance of the silica aerogel and combining the high volcanic ash effect of the metakaolin.
Preferably, the preparation method of the hydrotalcite comprises the following steps:
step a, adding Mg (NO)3)2·6H2O、Zn(NO3)2·3H2O and Al (NO)3)3·9H2Adding O and deionized water into a beaker respectively, and stirring for 10-20min at the rotating speed of 60-100r/min to obtain a magnesium nitrate solution, a zinc nitrate solution and an aluminum nitrate solution respectively;
step b, mixing urea and 60-75% ethanol solution according to the ratio of 20-25 g:100mL of the mixture is mixed to obtain a dispersion liquid a, the dispersion liquid a and deionized water are mixed according to the volume ratio of 1:0.75-0.85 to obtain a mixed liquid b, the mixed liquid b is transferred to a three-neck flask, the magnesium nitrate solution, the zinc nitrate solution and the aluminum nitrate solution prepared in the step a are added into the three-neck flask, and the mixture is stirred for 20-30min at the temperature of 50-60 ℃ and the rotation speed of 200-300r/min to obtain a mixture c;
and step c, transferring the mixture c into a reaction kettle, placing the reaction kettle into an oven, crystallizing at the constant temperature of 150-160 ℃ for 12-15h, cooling to room temperature, filtering, washing the filter cake for three times by using absolute ethyl alcohol and deionized water in sequence, and finally drying in an oven at the temperature of 100-105 ℃ for 5-8h to obtain the hydrotalcite.
Preferably, said Mg (NO) in step a3)2·6H2The dosage ratio of O to deionized water is 6-7 g:100 mL; al (NO)3)3·9H2The dosage ratio of O to deionized water is 3-4g:100 mL; zn (NO)3)2·3H2The dosage ratio of O to deionized water is 6-7 g:100 mL.
Preferably, the volume ratio of the mixed solution b, the zinc nitrate solution, the magnesium nitrate solution and the aluminum nitrate solution in the step b is 1:1:1: 1.
The present invention utilizes Mg (NO)3)2·6H2O、Zn(NO3)2·3H2O and Al (NO)3)3·9H2The preparation method comprises the steps of preparing ternary hydrotalcite containing Mg, Zn and Al elements by using an O as a raw material through a hydrothermal synthesis method, adding ethylene glycol, the ethylene glycol and deionized water into a hydrothermal reaction to form a microemulsion, wherein the ethylene glycol can form rod-shaped micelles in the emulsion, hydrotalcite particles grow in a water-phase cavity, and the shape of the water-phase cavity determines the form of synthetic ions.
Preferably, the sources of phosphogypsum are: the preparation method comprises the steps of treating phosphorite by sulfuric acid to prepare phosphoric acid, collecting solid waste residues generated in the preparation process, and calcining the solid waste residues at the temperature of 800-1000 ℃ to prepare the phosphogypsum.
Preferably, the content of needle and flaky particles in the stones is less than 25%, and the content of mud is less than 3%.
The fly ash is spherical, has small particle size and smooth surface, is commonly called as 'micro-beads', is mixed into cement like a ball, can improve the fluidity, cohesiveness and water retention of concrete and reduce water consumption, and the main chemical component of the fly ash is SiO2、Al2O3、Fe2O3The fly ash can play a role of micro aggregate in concrete due to small particles, can be filled into tiny gaps, can be physically filled and hydrated with reaction products, and has a simple mechanical filling effect compared with an inert micro aggregateBetter, can make the cement concrete more compact, improve its impervious performance, reduce the bleeding rate.
The phosphogypsum is added in the invention, and contains higher content of CaO and SO3The sodium polyacrylate can react with the components in the fly ash and the hydrotalcite to generate high-strength active substances, such as calcium silicate hydrate, calcium aluminate hydrate and calcium sulfate hydrate, the active substances can be filled in gaps of concrete to improve the compactness and the impermeability of the concrete, the aluminum ions in the aluminum phosphate and the aluminum potassium sulfate can react with hydration products in the concrete to generate crystals which are insoluble in water and are filled in capillary gaps to form a waterproof layer, the aluminum ions in the aluminum phosphate and the aluminum potassium sulfate can also form a complex network structure with calcium ions and methyl silicate ions in the concrete to improve the crack resistance and the fracture resistance of the concrete all day, the sodium polyacrylate can form insoluble salts with the calcium ions in the concrete to cause molecular crosslinking to gelate and precipitate, the thickness of a gel waterproof layer is improved, the durability of the concrete is improved, and the sodium polyacrylate can also serve as an auxiliary film agent, The action of the dispersant and the water-retaining agent can promote the fluidity of the waterproof agent mixture to be enhanced, thereby accelerating the uniform speed and the penetration speed of the mixture.
alpha-Al in the invention2O3The nanometer powder can fill the pores in the concrete structure, so that the concrete is more compact, the porosity is reduced, and simultaneously the interface bonding state between the aggregate and the cement paste, namely alpha-Al, is improved2O3The nano powder has high reaction activity, can quickly react with cement hydration products, and can adjust the proportion of the hydration products in a concrete structure, namely alpha-Al2O3The nanometer powder has nanometer particle size and uniform dispersion, and the nanometer particle and the production of hydration product form crystal nucleus effect to make Ca (OH)2Crystal grain refinement, alpha-Al2O3The surface of the nano powder has a plurality of unsaturated bonds which can be bonded with hydration products. The nano powder is used as a crystal nucleus, a calcium silicate hydrate gel phase is formed on the surface of the particle, and the loose calcium silicate hydrate gel is changed into a net structure taking the nano powder as a core, so that the concrete structure is more uniform and dense.
The invention has the beneficial effects that:
according to the invention, the self-made hydrotalcite and the metakaolin modified by a special method are added into the concrete, wherein the metakaolin is subjected to intercalation modification by adopting the hydrophobic silica aerogel, the micromolecular hydrophobic silica aerogel is inserted between the layered structures of the metakaolin, so that the interlamellar spacing of the metakaolin is increased, and the properties of compression resistance, bending resistance, crack resistance and the like of a concrete structure are obviously improved by utilizing the light, porous and low heat-conducting properties of the silica aerogel and combining the high volcanic ash effect of the metakaolin.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example 1 anti-cracking recycled concrete and preparation method thereof
Firstly, preparing the following raw materials in parts by weight:
25 parts of composite volcanic ash portland cement, 8 parts of sea sand, 42 parts of stones, 36 parts of deionized water, 27 parts of hydrotalcite, 42 parts of modified metakaolin, 33 parts of fly ash, 14 parts of phosphogypsum, 2 parts of aluminum hydrogen phosphate, 3 parts of potassium aluminum sulfate, and alpha-Al2O32 parts of nano powder, 0.8 part of sodium polyacrylate, 6 parts of basalt fiber, 2 parts of a water reducing agent, 1.8 parts of a CM-DPS deep penetration crystallization sealing waterproof agent, 13 parts of rubber emulsion and 3.5 parts of a silane coupling agent;
secondly, hydrotalcite, modified metakaolin, fly ash, phosphogypsum, aluminium phosphate dibasic, aluminium potassium sulfate, sodium polyacrylate and alpha-Al2O3Adding the nano powder and the basalt fiber into a ball mill, and performing ball milling for 45-50min to prepare the concrete anti-cracking additive;
thirdly, mixing and stirring the composite pozzolan portland cement, the sea sand, the stones and the deionized water, and gradually adding the CM-DPS deep penetration crystallization sealing waterproof agent, the rubber emulsion and the silane coupling agent in the stirring process; mixing for 15-20min, adding the prepared concrete anti-cracking additive and water reducing agent, and mixing for 20-25min to obtain anti-cracking recycled concrete;
the composite pozzolan portland cement is prepared by the following steps:
step A1, adding 10 parts of portland cement clinker, 2 parts of granulated blast furnace slag, 5 parts of limestone and 2 parts of pozzolan into a stirring barrel, stirring and mixing for 10min under the condition of 100r/min of rotation speed, then adding 2 parts of deionized water into the stirring barrel under the condition of reducing the rotation speed to 45r/min, stirring and mixing for 5min, and obtaining crude pozzolan portland cement;
step A2, adding sodium hydroxide with the concentration of 3mol/L into the pozzolan portland cement obtained in step A1, adjusting the pH value to 7.5, continuously adding 1 part of deionized water, and stirring and mixing for 5min to obtain composite pozzolan portland cement;
the sources of the phosphogypsum are as follows: the preparation method comprises the steps of treating phosphorite with sulfuric acid to prepare phosphoric acid, collecting solid waste residues generated in the preparation process, and calcining the solid waste residues at a high temperature of 800 ℃ to prepare the phosphogypsum.
The modified metakaolin is prepared by the following steps:
step S1, adding water glass and deionized water into a beaker according to the mass ratio of 1:4, stirring for 10min under the condition of the rotating speed of 150r/min, keeping the rotating speed unchanged, dropwise adding a hydrochloric acid solution with the concentration of 6mol/L into the beaker while stirring, adjusting the pH value to 1.5, and continuously stirring for 20min to obtain a silicic acid solution;
s2, dropwise adding an ammonia water solution with the concentration of 1mol/L into the silicic acid solution obtained in the step S1, stirring for 5min at the rotation speed of 100r/min, sealing with a preservative film, aging for 24h at normal temperature to obtain water glass gel, filling the water glass gel into a sealing bag, grinding, transferring into a beaker, adding absolute ethyl alcohol, trimethylchlorosilane and n-hexane into the beaker, stirring for 30min at the rotation speed of 200r/min, filtering, washing a filter cake with deionized water for 3 times, and finally drying the filter cake for 4h at the temperature of 40 ℃, 60 ℃, 80 ℃, 100 ℃ and 120 ℃ respectively at normal pressure to obtain hydrophobic silica aerogel;
and step S3, adding the hydrophobic silica aerogel, the metakaolin and the absolute ethyl alcohol into a beaker, ultrasonically dispersing for 20min under the condition of frequency of 30kHz, then aging for 22h under the condition of water bath at 40-50 ℃, then filtering, washing a filter cake for 3 times by using deionized water, and finally drying in an oven at 100 ℃ to constant weight to obtain the modified metakaolin.
In the step S2, the volume ratio of the silicic acid solution to the 1mol/L ammonia water solution to the absolute ethyl alcohol to the trimethylchlorosilane to the normal hexane is 8:0.1:15:0.3: 0.3; in the step S3, the ratio of the hydrophobic silica aerogel to the metakaolin to the absolute ethyl alcohol is 1 g: 2 g: 5 mL.
The preparation method of the hydrotalcite comprises the following steps:
step a, adding Mg (NO)3)2·6H2O、Zn(NO3)2·3H2O and Al (NO)3)3·9H2Adding O and deionized water into a beaker respectively, and stirring for 10min under the condition that the rotating speed is 60r/min to obtain a magnesium nitrate solution, a zinc nitrate solution and an aluminum nitrate solution respectively;
step b, mixing urea and ethanol solution with volume fraction of 65% according to the dosage ratio of 20 g:100mL of the dispersion liquid is mixed to obtain dispersion liquid a, and then the dispersion liquid a and deionized water are mixed according to the volume ratio of 1:0.75 to obtain mixed liquid b; transferring the mixed solution b into a three-neck flask, adding the magnesium nitrate solution, the zinc nitrate solution and the aluminum nitrate solution prepared in the step a into the three-neck flask, and stirring for 20min at the temperature of 50 ℃ and the rotating speed of 200r/min to obtain a mixture c;
and c, transferring the mixture c into a reaction kettle, placing the reaction kettle into an oven, crystallizing at the constant temperature of 150 ℃ for 12 hours, cooling to room temperature, filtering, washing the filter cake with absolute ethyl alcohol and deionized water for three times in sequence, and finally drying in the oven at the temperature of 100 ℃ for 5 hours to obtain the hydrotalcite.
Wherein, the Mg (NO) in the step a3)2·6H2The dosage ratio of O to deionized water is 6 g:100 mL; al (NO)3)3·9H2The dosage ratio of O to deionized water is 3g to 100 mL; zn (NO)3)2·3H2Of O and deionised waterThe dosage ratio is 6 g:100 mL; and c, in the step b, the volume ratio of the mixed solution b to the zinc nitrate solution to the magnesium nitrate solution to the aluminum nitrate solution is 1:1:1: 1.
Example 2 anti-cracking recycled concrete and preparation method thereof
Firstly, preparing the following raw materials in parts by weight:
30 parts of composite volcanic ash portland cement, 15 parts of sea sand, 50 parts of stones and 45 parts of deionized water; 30 parts of hydrotalcite, 50 parts of modified metakaolin, 40 parts of fly ash, 15 parts of phosphogypsum, 5 parts of aluminium hydrogen phosphate, 4 parts of potassium aluminium sulfate and alpha-Al2O33 parts of nano powder, 1 part of sodium polyacrylate, 10 parts of basalt fiber, 1.5 parts of a water reducing agent, 2 parts of a CM-DPS deep penetration crystallization sealing waterproof agent, 14 parts of rubber emulsion and 4 parts of a silane coupling agent;
secondly, hydrotalcite, modified metakaolin, fly ash, phosphogypsum, aluminium phosphate dibasic, aluminium potassium sulfate, sodium polyacrylate and alpha-Al2O3Adding the nano powder and the basalt fiber into a ball mill, and performing ball milling for 45-50min to prepare the concrete anti-cracking additive;
thirdly, mixing and stirring the composite pozzolan portland cement, the sea sand, the stones and the deionized water, and gradually adding the CM-DPS deep penetration crystallization sealing waterproof agent, the rubber emulsion and the silane coupling agent in the stirring process; mixing for 20min, adding the prepared concrete anti-cracking additive and water reducing agent, and mixing for 25min to obtain anti-cracking recycled concrete;
the composite pozzolan portland cement is prepared by the following steps:
step A1, adding 10 parts of portland cement clinker, 2 parts of granulated blast furnace slag, 5 parts of limestone and 2 parts of pozzolan into a stirring barrel, stirring and mixing for 10min under the condition of 100r/min of rotation speed, then adding 2 parts of deionized water into the stirring barrel under the condition of reducing the rotation speed to 45r/min, stirring and mixing for 5min, and obtaining crude pozzolan portland cement;
step A2, adding sodium hydroxide with the concentration of 3mol/L into the pozzolan portland cement obtained in step A1, adjusting the pH value to 8.0, continuously adding 1 part of deionized water, and stirring and mixing for 5min to obtain composite pozzolan portland cement;
the sources of the phosphogypsum are as follows: the preparation method comprises the steps of treating phosphorite with sulfuric acid to prepare phosphoric acid, collecting solid waste residues generated in the preparation process, and calcining the solid waste residues at a high temperature of 800 ℃ to prepare the phosphogypsum.
The modified metakaolin is prepared by the following steps:
step S1, adding water glass and deionized water into a beaker according to the mass ratio of 1:4, stirring for 10min under the condition of the rotating speed of 150r/min, keeping the rotating speed unchanged, dropwise adding a hydrochloric acid solution with the concentration of 6mol/L into the beaker while stirring, adjusting the pH value to 1.5, and continuously stirring for 20min to obtain a silicic acid solution;
s2, dropwise adding an ammonia water solution with the concentration of 1mol/L into the silicic acid solution obtained in the step S1, stirring for 5min at the rotation speed of 100r/min, sealing with a preservative film, aging for 24h at normal temperature to obtain water glass gel, filling the water glass gel into a sealing bag, grinding, transferring into a beaker, adding absolute ethyl alcohol, trimethylchlorosilane and n-hexane into the beaker, stirring for 30min at the rotation speed of 200r/min, filtering, washing a filter cake with deionized water for 3 times, and finally drying the filter cake for 4h at the temperature of 40 ℃, 60 ℃, 80 ℃, 100 ℃ and 120 ℃ respectively at normal pressure to obtain hydrophobic silica aerogel;
and step S3, adding the hydrophobic silica aerogel, the metakaolin and the absolute ethyl alcohol into a beaker, ultrasonically dispersing for 20min under the condition of frequency of 30kHz, then aging for 22h under the condition of water bath at 40-50 ℃, then filtering, washing a filter cake for 3 times by using deionized water, and finally drying in an oven at 100 ℃ to constant weight to obtain the modified metakaolin.
In the step S2, the volume ratio of the silicic acid solution to the 1mol/L ammonia water solution to the absolute ethyl alcohol to the trimethylchlorosilane to the normal hexane is 8:0.1:15:0.3: 0.3; in the step S3, the ratio of the hydrophobic silica aerogel to the metakaolin to the absolute ethyl alcohol is 1 g: 2 g: 5 mL.
The preparation method of the hydrotalcite comprises the following steps:
step a, adding Mg (NO)3)2·6H2O、Zn(NO3)2·3H2O and Al (NO)3)3·9H2Adding O and deionized water into a beaker respectively, and stirring for 10min under the condition that the rotating speed is 60r/min to obtain a magnesium nitrate solution, a zinc nitrate solution and an aluminum nitrate solution respectively;
step b, mixing urea and ethanol solution with volume fraction of 65% according to the dosage ratio of 20 g:100mL of the dispersion liquid is mixed to obtain dispersion liquid a, and then the dispersion liquid a and deionized water are mixed according to the volume ratio of 1:0.75 to obtain mixed liquid b; transferring the mixed solution b into a three-neck flask, adding the magnesium nitrate solution, the zinc nitrate solution and the aluminum nitrate solution prepared in the step a into the three-neck flask, and stirring for 20min at the temperature of 50 ℃ and the rotating speed of 200r/min to obtain a mixture c;
and c, transferring the mixture c into a reaction kettle, placing the reaction kettle into an oven, crystallizing at the constant temperature of 150 ℃ for 12 hours, cooling to room temperature, filtering, washing the filter cake with absolute ethyl alcohol and deionized water for three times in sequence, and finally drying in the oven at the temperature of 100 ℃ for 5 hours to obtain the hydrotalcite.
Wherein, the Mg (NO) in the step a3)2·6H2The dosage ratio of O to deionized water is 6 g:100 mL; al (NO)3)3·9H2The dosage ratio of O to deionized water is 3g to 100 mL; zn (NO)3)2·3H2The dosage ratio of O to deionized water is 6 g:100 mL; and c, in the step b, the volume ratio of the mixed solution b to the zinc nitrate solution to the magnesium nitrate solution to the aluminum nitrate solution is 1:1:1: 1.
Example 3
Firstly, preparing the following raw materials in parts by weight:
18 parts of composite volcanic ash portland cement, 10 parts of sea sand, 30 parts of stones and 30 parts of deionized water; 20 parts of hydrotalcite, 30 parts of modified metakaolin, 22 parts of fly ash, 11 parts of phosphogypsum, 2 parts of aluminium hydrogen phosphate, 2 parts of aluminium potassium sulfate and alpha-Al2O32 parts of nano powder, 0.5 part of sodium polyacrylate, 6 parts of basalt fiber, 1.5 parts of a water reducing agent, 1.5 parts of a CM-DPS deep penetration crystallization sealing waterproof agent, 12 parts of rubber emulsion and 3 parts of a silane coupling agent;
secondly, hydrotalcite, modified metakaolin, fly ash, phosphogypsum,Aluminium hydrogen phosphate, aluminium potassium sulfate, sodium polyacrylate, alpha-Al2O3Adding the nano powder and the basalt fiber into a ball mill, and performing ball milling for 45-50min to prepare the concrete anti-cracking additive;
thirdly, mixing and stirring the composite pozzolan portland cement, the sea sand, the stones and the deionized water, and gradually adding the CM-DPS deep penetration crystallization sealing waterproof agent, the rubber emulsion and the silane coupling agent in the stirring process; mixing for 20min, adding the prepared concrete anti-cracking additive and water reducing agent, and mixing for 25min to obtain anti-cracking recycled concrete;
the composite pozzolan portland cement is prepared by the following steps:
step A1, adding 10 parts of portland cement clinker, 2 parts of granulated blast furnace slag, 5 parts of limestone and 2 parts of pozzolan into a stirring barrel, stirring and mixing for 10min under the condition of 100r/min of rotation speed, then adding 2 parts of deionized water into the stirring barrel under the condition of reducing the rotation speed to 45r/min, stirring and mixing for 5min, and obtaining crude pozzolan portland cement;
step A2, adding sodium hydroxide with the concentration of 3mol/L into the pozzolan portland cement obtained in step A1, adjusting the pH value to 8.0, continuously adding 1 part of deionized water, and stirring and mixing for 5min to obtain composite pozzolan portland cement;
the sources of the phosphogypsum are as follows: the preparation method comprises the steps of treating phosphorite with sulfuric acid to prepare phosphoric acid, collecting solid waste residues generated in the preparation process, and calcining the solid waste residues at a high temperature of 800 ℃ to prepare the phosphogypsum.
The modified metakaolin is prepared by the following steps:
step S1, adding water glass and deionized water into a beaker according to the mass ratio of 1:4, stirring for 10min under the condition of the rotating speed of 150r/min, keeping the rotating speed unchanged, dropwise adding a hydrochloric acid solution with the concentration of 6mol/L into the beaker while stirring, adjusting the pH value to 1.5, and continuously stirring for 20min to obtain a silicic acid solution;
s2, dropwise adding an ammonia water solution with the concentration of 1mol/L into the silicic acid solution obtained in the step S1, stirring for 5min at the rotation speed of 100r/min, sealing with a preservative film, aging for 24h at normal temperature to obtain water glass gel, filling the water glass gel into a sealing bag, grinding, transferring into a beaker, adding absolute ethyl alcohol, trimethylchlorosilane and n-hexane into the beaker, stirring for 30min at the rotation speed of 200r/min, filtering, washing a filter cake with deionized water for 3 times, and finally drying the filter cake for 4h at the temperature of 40 ℃, 60 ℃, 80 ℃, 100 ℃ and 120 ℃ respectively at normal pressure to obtain hydrophobic silica aerogel;
and step S3, adding the hydrophobic silica aerogel, the metakaolin and the absolute ethyl alcohol into a beaker, ultrasonically dispersing for 20min under the condition of frequency of 30kHz, then aging for 22h under the condition of water bath at 40-50 ℃, then filtering, washing a filter cake for 3 times by using deionized water, and finally drying in an oven at 100 ℃ to constant weight to obtain the modified metakaolin.
In the step S2, the volume ratio of the silicic acid solution to the 1mol/L ammonia water solution to the absolute ethyl alcohol to the trimethylchlorosilane to the normal hexane is 8:0.1:15:0.3: 0.3; in the step S3, the ratio of the hydrophobic silica aerogel to the metakaolin to the absolute ethyl alcohol is 1 g: 2 g: 5 mL.
The preparation method of the hydrotalcite comprises the following steps:
step a, adding Mg (NO)3)2·6H2O、Zn(NO3)2·3H2O and Al (NO)3)3·9H2Adding O and deionized water into a beaker respectively, and stirring for 10min under the condition that the rotating speed is 60r/min to obtain a magnesium nitrate solution, a zinc nitrate solution and an aluminum nitrate solution respectively;
step b, mixing urea and ethanol solution with volume fraction of 65% according to the dosage ratio of 20 g:100mL of the dispersion liquid is mixed to obtain dispersion liquid a, and then the dispersion liquid a and deionized water are mixed according to the volume ratio of 1:0.75 to obtain mixed liquid b; transferring the mixed solution b into a three-neck flask, adding the magnesium nitrate solution, the zinc nitrate solution and the aluminum nitrate solution prepared in the step a into the three-neck flask, and stirring for 20min at the temperature of 50 ℃ and the rotating speed of 200r/min to obtain a mixture c;
and c, transferring the mixture c into a reaction kettle, placing the reaction kettle into an oven, crystallizing at the constant temperature of 150 ℃ for 12 hours, cooling to room temperature, filtering, washing the filter cake with absolute ethyl alcohol and deionized water for three times in sequence, and finally drying in the oven at the temperature of 100 ℃ for 5 hours to obtain the hydrotalcite.
Wherein, the Mg (NO) in the step a3)2·6H2The dosage ratio of O to deionized water is 6 g:100 mL; al (NO)3)3·9H2The dosage ratio of O to deionized water is 3g to 100 mL; zn (NO)3)2·3H2The dosage ratio of O to deionized water is 6 g:100 mL; and c, in the step b, the volume ratio of the mixed solution b to the zinc nitrate solution to the magnesium nitrate solution to the aluminum nitrate solution is 1:1:1: 1.
Comparative example 1, which is different from example 1 in that,
the modified metakaolin described in example 1 was replaced with unmodified metakaolin, and the remaining raw materials and preparation were unchanged.
Comparative example 2, which is different from example 1,
the hydrotalcite from example 1 was removed and the remaining raw materials and preparation were unchanged.
Comparative example 3, which is different from example 1,
hydrophobic silica aerogel modified montmorillonite is adopted to replace the modified higher-level soil in example 1, and other raw materials and the preparation process are not changed.
The preparation method of the hydrophobic silica aerogel modified montmorillonite is similar to that of the modified higher territorial earth in the embodiment 1 of the invention, and the difference is only that the montmorillonite is adopted to replace the higher territorial earth.
Test one, working Performance test
The workability of the anti-cracking recycled concrete obtained in the examples 1-3 and the comparative examples 1-3 was tested according to GB/T50080-.
TABLE 1 test results
Figure BDA0002800372890000121
Test II, crack resistance test
The concrete porous cracking resistance prepared in examples 1-3 and comparative examples 1-3 was tested by the ring-type constrained cracking method, which specifically comprises the following steps: after pouring, compacting and leveling, each group of concrete slab test pieces are moved into a constant temperature and humidity drying chamber and placed for 72 hours in the environment with the wind speed (5 +/-0.5) m/s, the temperature (20 +/-2) DEG C and the relative humidity (60 +/-5%). The number of cracks is recorded every 4h, the width and the length of each crack are measured, the measurement result of 24h after the concrete sample is stirred and added with water is taken as the concrete crack resistance index, and the detection result is shown in the following table 2.
TABLE 2 results of crack resistance test
Figure BDA0002800372890000122
Figure BDA0002800372890000131
From the table, the concrete prepared in the embodiments 1 to 3 of the present invention has good crack resistance, and meanwhile, the other comparative examples are analyzed, so that if the modified metakaolin is not added, the crack resistance of the concrete is significantly reduced.
The foregoing is merely exemplary and illustrative of the principles of the present invention and various modifications, additions and substitutions of the specific embodiments described herein may be made by those skilled in the art without departing from the principles of the present invention or exceeding the scope of the claims set forth herein.

Claims (10)

1. The anti-cracking recycled concrete and the preparation method thereof are characterized by comprising the following steps:
firstly, preparing the following raw materials in parts by weight:
15-30 parts of composite volcanic ash portland cement, 10-15 parts of sea sand, 30-50 parts of pebbles, 30-50 parts of deionized water, 20-30 parts of hydrotalcite, 30-50 parts of modified metakaolin, 20-40 parts of fly ash, 10-15 parts of phosphogypsum, 2-5 parts of aluminum hydrogen phosphate, 2-4 parts of aluminum potassium sulfate, alpha-Al2O32-3 parts of nano powder, 0.1-1 part of sodium polyacrylate, 5-10 parts of basalt fiber, 1.5-2 parts of water reducing agent, 1.5-2 parts of CM-DPS deep penetration crystallization sealing waterproof agent, 10.5-14 parts of rubber emulsion and 3-4 parts of silane coupling agent;
secondly, hydrotalcite, modified metakaolin, fly ash, phosphogypsum, aluminium phosphate dibasic, aluminium potassium sulfate, sodium polyacrylate and alpha-Al2O3Adding the nano powder and the basalt fiber into a ball mill, and performing ball milling for 45-50min to prepare the concrete anti-cracking additive;
thirdly, mixing and stirring the composite pozzolan portland cement, the sea sand, the stones and the deionized water, and gradually adding 3 parts of CM-DPS deep penetration crystallization sealing waterproof agent, rubber emulsion and silane coupling agent in the stirring process; and mixing for 15-20min, adding the prepared concrete anti-cracking additive and the water reducing agent, and mixing for 20-25min to obtain the anti-cracking recycled concrete.
2. The crack-resistant recycled concrete and the preparation method thereof according to claim 1, wherein the composite pozzolan portland cement is prepared by the following steps:
step A1, adding 10 parts of portland cement clinker, 2 parts of granulated blast furnace slag, 5 parts of limestone and 2 parts of pozzolan into a stirring barrel, stirring and mixing for 7-12min under the condition of the rotating speed of 75-110r/min, then adding 2 parts of deionized water into the stirring barrel under the condition of reducing the rotating speed to 40-55r/min, and stirring and mixing for 3-5min to obtain crude pozzolan portland cement;
and A2, adding 3mol/L sodium hydroxide into the pozzolan portland cement obtained in the step A1, adjusting the pH value to 7.5-8, continuously adding 1 part of deionized water, and stirring and mixing for 3-5min to obtain the composite pozzolan portland cement.
3. The crack-resistant recycled concrete and the preparation method thereof according to claim 1, wherein the modified metakaolin is prepared by the following steps:
step S1, adding water glass and deionized water into a beaker according to the mass ratio of 1:4, stirring for 10-15min under the condition that the rotating speed is 150-;
s2, dropwise adding 1mol/L ammonia water solution into the silicic acid solution obtained in the step S1, stirring for 5min under the condition that the rotation speed is 100 plus 150r/min, sealing by a preservative film, aging for 24h at normal temperature to obtain water glass gel, filling the water glass gel into a sealing bag, grinding, transferring into a beaker, adding absolute ethyl alcohol, trimethylchlorosilane and n-hexane into the beaker, stirring for 30-60min under the condition that the rotation speed is 200 plus 300r/min, filtering, washing a filter cake for 3-5 times by deionized water, and finally drying for 4h at 40 ℃, 60 ℃, 80 ℃, 100 ℃ and 120 ℃ respectively under normal pressure to obtain hydrophobic silica aerogel;
step S3, adding hydrophobic silica aerogel, metakaolin and absolute ethyl alcohol into a beaker, ultrasonically dispersing for 20-40min under the condition of frequency of 30-50kHz, then aging for 22-24h under the condition of water bath at 40-50 ℃, then filtering, washing a filter cake for 3-5 times by using deionized water, and finally drying in an oven at 100-105 ℃ to constant weight to prepare the modified metakaolin.
4. The crack-resistant recycled concrete and the preparation method thereof as claimed in claim 3, wherein the volume ratio of the silicic acid solution, 1mol/L ammonia water solution, absolute ethyl alcohol, trimethylchlorosilane and n-hexane in step S2 is 8:0.1-0.3:15:0.3-0.5: 0.3-0.5.
5. The crack-resistant recycled concrete and the preparation method thereof as claimed in claim 3 or 4, wherein the amount ratio of the hydrophobic silica aerogel, the metakaolin and the absolute ethyl alcohol in the step S3 is 1 g: 2-4 g: 5-10 mL.
6. The crack-resistant recycled concrete and the preparation method thereof according to claim 1, wherein the preparation method of the hydrotalcite comprises the following steps:
step a, adding Mg (NO)3)2·6H2O、Zn(NO3)2·3H2O and Al (NO)3)3·9H2Adding O and deionized water into a beaker respectively, and stirring for 10-20min at the rotating speed of 60-100r/min to obtain a magnesium nitrate solution, a zinc nitrate solution and an aluminum nitrate solution respectively;
step b, mixing urea and 60-75% ethanol solution according to the ratio of 20-25 g:100mL of the mixture is mixed to obtain a dispersion liquid a, the dispersion liquid a and deionized water are mixed according to the volume ratio of 1:0.75-0.85 to obtain a mixed liquid b, the mixed liquid b is transferred to a three-neck flask, the magnesium nitrate solution, the zinc nitrate solution and the aluminum nitrate solution prepared in the step a are added into the three-neck flask, and the mixture is stirred for 20-30min at the temperature of 50-60 ℃ and the rotation speed of 200-300r/min to obtain a mixture c;
and step c, transferring the mixture c into a reaction kettle, placing the reaction kettle into an oven, crystallizing at the constant temperature of 150-160 ℃ for 12-15h, cooling to room temperature, filtering, washing the filter cake for three times by using absolute ethyl alcohol and deionized water in sequence, and finally drying in an oven at the temperature of 100-105 ℃ for 5-8h to obtain the hydrotalcite.
7. The crack-resistant recycled concrete and the preparation method thereof as claimed in claim 5, wherein said Mg (NO) in step a3)2·6H2The dosage ratio of O to deionized water is 6-7 g:100 mL; al (NO)3)3·9H2The dosage ratio of O to deionized water is 3-4g:100 mL; zn (NO)3)2·3H2The dosage ratio of O to deionized water is 6-7 g:100 mL.
8. The crack-resistant recycled concrete and the preparation method thereof as claimed in claim 5, wherein the volume ratio of the mixed solution b, the zinc nitrate solution, the magnesium nitrate solution and the aluminum nitrate solution in the step b is 1:1:1: 1.
9. The crack-resistant recycled concrete and the preparation method thereof according to claim 1, wherein the sources of the phosphogypsum are as follows: the preparation method comprises the steps of treating phosphorite by sulfuric acid to prepare phosphoric acid, collecting solid waste residues generated in the preparation process, and calcining the solid waste residues at the temperature of 800-1000 ℃ to prepare the phosphogypsum.
10. The crack-resistant recycled concrete and the preparation method thereof as claimed in claim 1, wherein the content of needle and flake particles in the stones is less than 25%, and the content of mud is less than 3%.
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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113651337A (en) * 2021-09-27 2021-11-16 浙江加州国际纳米技术研究院台州分院 Preparation method of intercalation modified C-S-H gel nano dispersion liquid
CN114956733A (en) * 2022-06-10 2022-08-30 日照海工研新材料有限公司 High-strength anti-erosion marine concrete and preparation method thereof
CN115140740A (en) * 2022-06-29 2022-10-04 中南大学 Preparation method of layered double hydroxide hydrophobic silica composite aerogel

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113651337A (en) * 2021-09-27 2021-11-16 浙江加州国际纳米技术研究院台州分院 Preparation method of intercalation modified C-S-H gel nano dispersion liquid
CN114956733A (en) * 2022-06-10 2022-08-30 日照海工研新材料有限公司 High-strength anti-erosion marine concrete and preparation method thereof
CN115140740A (en) * 2022-06-29 2022-10-04 中南大学 Preparation method of layered double hydroxide hydrophobic silica composite aerogel
CN115140740B (en) * 2022-06-29 2023-06-16 中南大学 Preparation method of layered double hydroxide hydrophobic silica composite aerogel

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