CN107352913A - A kind of super high strength high performance fiber concrete of C180 strength grades and preparation method thereof - Google Patents
A kind of super high strength high performance fiber concrete of C180 strength grades and preparation method thereof Download PDFInfo
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- CN107352913A CN107352913A CN201710703018.1A CN201710703018A CN107352913A CN 107352913 A CN107352913 A CN 107352913A CN 201710703018 A CN201710703018 A CN 201710703018A CN 107352913 A CN107352913 A CN 107352913A
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B28/00—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements
- C04B28/02—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements containing hydraulic cements other than calcium sulfates
- C04B28/04—Portland cements
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- 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
-
- 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
- C04B14/022—Carbon
- C04B14/026—Carbon of particular shape, e.g. nanotubes
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2201/00—Mortars, concrete or artificial stone characterised by specific physical values
- C04B2201/50—Mortars, concrete or artificial stone characterised by specific physical values for the mechanical strength
-
- 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
- C04B2201/52—High compression strength concretes, i.e. with a compression strength higher than about 55 N/mm2, e.g. reactive powder concrete [RPC]
-
- 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
Abstract
The invention discloses a kind of super high strength high performance fiber concrete of C180 strength grades and preparation method thereof, the mass parts composition of the concrete is as follows：505 parts of cement, 70 parts of water, 1000 parts of rubble, 770 parts of fine aggregate, 70 parts of flyash, 78 parts of rice hull ash, 118 parts of silicon ash, 15 parts of water reducer, 10 parts of exciting agent, 1.7 parts of cellulose fibre, 43 parts of hydroxyl modification carbon nano tube dispersion liquid, 45 parts of graphene oxide dispersion, 2.7 parts of defoamer.The concrete of preparation has higher toughness and excellent endurance quality, there is higher adhesion strength between shaped steel, compression strength reaches 188.63MPa, rupture strength reaches 36.44MPa, split tensile strength reaches 15.38MPa, adhesion strength between shaped steel reaches 7.68MPa, and chloride ion resistance grade reaches VI grade.For in reinforced concrete composite structure, can effectively play the cooperative work performance between shaped steel and concrete, make up bond between steel and concrete poor performance, the deficiency of the two respective mechanical property can not be given full play to.
Description
Technical field
The invention belongs to New Building Materials field, is that one kind mixes rice hull ash, cellulose fibre, modified carbon nano-tube and oxygen
High intensity, high tenacity and the high durability concrete of graphite alkene, and in particular to a kind of C180 strength grades with high tenacity
Super high strength high performance fiber concrete and preparation method thereof.
Background technology
The tensile strength of normal concrete and cement-based material is low, poor toughness, in hardening process or under external loads effect
A large amount of microcracks can be produced, make Cl-、SO4 2-Deng harmful ion and CO2Inside concrete is invaded Deng pernicious gas, accelerates concrete
The erosion of structure, the durability of concrete or cement-base composite material structure is had a strong impact on, reduce structure service life.
CNT is a kind of one dimension fibre material with Nano grade diameter and micron level length, and its draw ratio is high
Up to 100-1000, modulus of elasticity (can reach 1TPa or so) is about 5 times of steel and density is the 1/6 of steel；Carbon is received
The tensile strength of mitron then can reach 60-150GPa, and compressive strength 100-170GPa, breaking strain is in 30-50% scopes.Cause
Its excellent Physical and mechanical properties, CNT is set to turn into preferable composite reinforcing fiber.But due to CNT
Surface is completely smooth, defect is few, lacks active group, and the relative solubility in water and various solution or composite is relatively low,
In addition larger Van der Waals force between CNT be present, very big surface free energy at surface be present, thus CNT it
Between spontaneous reunion or winding easily occurs, have a strong impact on that CNT is dispersed in some polymer.The present invention makes
Multi-walled carbon nanotube is disperseed and is ultrasonically treated with surfactant, CNT is not being cut off and is not destroying its surface knot
On the basis of structure, obtain can in water stable dispersion modified multiwalled carbon nanotube dispersion liquid so that it can be used in mixing
In solidifying soil, its microfibre toughening effect is given full play to.
And graphene is also intensity and hardness highest crystal structure in current material, tensile strength and modulus of elasticity difference
It can reach 125GPa and 1.1TPa.Single-layer graphene thickness is only about 0.35nm, is most thin by two in the nature having now been found that
Material is tieed up, there is higher specific surface area, can be combined well with polymer.But due to being sp2 hydridization knots in graphene face
Structure, cause mutual absorption in the presence of very strong molecular attraction between nano-particle, cause graphene to reunite together, it is impossible to stable dispersion
In the polymer and its effect is played, or even intrinsic silicon can be caused defect occur.And the graphene monolithic Jing Guo oxidation processes
Surface introduces the oxygen-containing functional groups such as many hydroxyls, carboxyl, can be dispersed in water, but graphene oxide is in alkali
Property under the conditions of easily flocculate, it is unfavorable that this disperses in cement for graphene oxide, or even can cause the intensity of concrete
Loss.The present invention by add dispersant be prepared for can in cement stable dispersion graphene oxide dispersion, can
It is enough in concrete, improves the combination property of concrete.
In order to overcome the fragility of normal concrete and high performance concrete and existing fiber concrete and cement base compound
The shortcomings that material, using the cellulose fibre with water storage function and toughening effect and the rice hull ash with ultrafine micropore structure
(rice hull ash with loose structure can absorb moisture), " the interior maintenance action " of two kinds of materials can promote the aquation of binder materials
Process；In addition, by adding modified carbon nano-tube and graphene oxide both components in concrete, to improve concrete
Toughness, and make binder materials in hydration process aquation more fully, improve the crystal shape or even concrete of hydrated product
The compactness extent of internal structure, the intensity and endurance quality for improving concrete are finally reached, and lift its toughness, plasticity and tension
The target of intensity.
The content of the invention
It is an object of the invention to provide a kind of super high strength high performance fiber concrete of C180 strength grades and its preparation side
Method, novelty of the invention tie up in concrete and are mixed with the cellulose fibre with toughness reinforcing and interior maintenance action, supported with interior
A kind of carbon-free rice hull ash of novel active mineral admixture of shield effect, and the more walls of modification with toughness reinforcing and nano-filled effect
CNT and graphene oxide.Synergy between each component can promote binder materials aquation more abundant, improve mixed
Microcosmic composition inside solidifying soil, reduces detrimental voids quantity, makes concrete inner structure more closely knit, finally prepares with super
High intensity, high tenacity, high-durability, the novel high-performance fiber concrete material of high volume stability.
To achieve the above object, technical scheme disclosed by the invention is：
A kind of super high strength high performance fiber concrete of C180 strength grades, include the raw material of following mass fractions：
505 parts of cement, 70 parts of water, 1000 parts of rubble, 770 parts of fine aggregate, 70 parts of flyash, 78 parts of rice hull ash, silicon ash 118
Part, 15 parts of water reducer, 10 parts of exciting agent, 1.7 parts of cellulose fibre, 43 parts of hydroxyl modification carbon nano tube dispersion liquid, graphite oxide
45 parts of alkene dispersion liquid, 2.7 parts of defoamer.
The cement is the 62.5R portland cements of P I, and it is good with poly carboxylic acid series water reducer compatibility.
The fine aggregate uses mass ratio as 8:The good high grade quartz sand of 2 scleroid river sand and grading, river sand
Modulus of fineness is 2.8-3.2, and dioxide-containing silica is not less than 98% in quartz sand, particle diameter 0.3-0.6mm, density 2.62g/
cm3。
The rubble selection grading is good, hard, the shaggy basaltic broken stone of densification, by the 5- of continuous size fraction
10mm, 10-16mm rubble are according to 7:3 mass ratio is used in mixed way, and parent rock strength is not less than 250MPa, and maximum particle diameter is not
More than 16mm.
The flyash uses the high-quality I grade of special fine powdered coal of power plant, and water demand ratio is not more than 95%, and specific surface area should be greater than
600m2/kg。
The mass percent of silica is not less than 93% in the silicon ash, and pozzolanic activity index is more than 95%, averagely
0.1 μm -0.3 μm of particle diameter, specific surface area are more than 15m2/g。
The water reducer is polycarboxylate high performance water-reducing agent, and solid content 20%, pH value 7-8, water-reducing rate is 30%
More than, 7d, 28d compressive strength rate are not less than 180%；
The defoamer uses U.S.'s Hexion AXILAT DF6352DD defoamers.
The rice hull ash is to be passed through to burn, using ball mill grinding 30-40min at a temperature of 650-800 DEG C by rice husk
Obtained grey purple powder, its dioxide-containing silica are 93.6%, and particle diameter is 5-25 μm, and specific surface area is more than 70m2/g。
The exciting agent is Organic-inorganic composite exciting agent, is formed according to the raw material compounding of following mass percent meters：
98% waterglass, 2% triethanolamine；
The modulus of the water glass solution is 1.2, is molten for 3.4 waterglass by industrial sodium hydroxide and commercially available modulus
What liquid was formulated.
The cellulose fibre is UF500 cellulose fibres, length 2-3mm, a diameter of 15-20 μm, tensile strength >=
900MPa, modulus of elasticity >=8.5GPa, fracture elongation reach 10%, proportion 1.1g/cm3, there is good hydrophily, compared with
High bond stress and acid-proof alkaline.
The carbon nano tube dispersion liquid is hydroxyl modification carbon nano tube dispersion liquid, is to pass through alkali successively by multi-walled carbon nanotube
Hydro-thermal reaction under the conditions of property obtains hydroxyl modification multi-wall carbon nano-tube pipe powder, then with surfactant and auxiliary agent in deionization
Obtained in water after decentralized processing.
The preparation method of the hydroxyl modification carbon nano tube dispersion liquid is as follows：
1) compound concentration is the 2.0M NaOH aqueous solution, weighs the NaOH water that 2 parts of multi-walled carbon nanotubes add 100 parts of preparations
In solution, 5min is ultrasonically treated；Carbon nano tube dispersion liquid is poured into autoclave, 180 DEG C of reaction 120min after sealing；It is cold afterwards
But to room temperature, centrifuge, add deionized water and dilute and wash, remove clear liquid；Ultrasonic 10min again, stirring, vinylidene chloride filter
Membrane filtration, gained solid product are washed to filtrate as neutrality；12h is dried at 40 DEG C, obtains the oxygen-containing functional groups such as surface hydroxyl
Modified multiwalled carbon nanotube；
2) modified multiwalled carbon nanotube, the surface-active of the oxygen-containing functional groups such as the surface hydroxyl prepared in step 1) are weighed
98 parts of 0.5 part of agent, 0.1 part of defoamer and deionized water, surfactant, defoamer and modified carbon nano-tube are distributed to successively
In deionized water, stirring, CNT is set to be soaked completely by aqueous surfactant solution；It is ultrasonically treated 30min；Afterwards to scattered
Liquid carries out centrifugal sedimentation；
3) supernatant liquid is crossed into 300 mesh filter clothes, obtains carbon nano tube dispersion liquid 1；The CNT that bottom precipitation is reunited
Ultrasonic 60min is carried out again according to step 2), obtains carbon nano tube dispersion liquid 2, hydroxyl modification in carbon nano tube dispersion liquid 1 and 2
Multi-walled carbon nanotube uniform and stable can disperse in water.
The average caliber of the multi-walled carbon nanotube is 40-50nm, and length is 10-20 μm, purity >=98%.
The surfactant is Triton X-100, pH=7.0,63 DEG C of cloud point, is a kind of nonionic table
Face activating agent；The defoamer is U.S.'s Hexion AXILAT DF6352DD defoamers.
The graphene oxide dispersion is obtained by following methods：
(1) 100 parts of deionized waters are added in 1 part of graphene oxide powder, using ultrasonic machine ultrasonic disperse 30min, are obtained
To finely dispersed graphene oxide dispersion；
(2) 0.1 part of water reducer is added in 50 parts of deionized waters, stirred, then add oxygen prepared by step (1)
Graphite alkene dispersion liquid, using special-purpose stirring machine stir 90s, finally give can be dispersed in cement graphene oxide
Dispersion liquid.
The graphene oxide is powdered, purity >=98%, and 10 μm -20 μm of diameter, its surface has substantial amounts of oxygen-containing
Group, there is higher decentralization in water；
The water reducer is polycarboxylate high performance water-reducing agent, solid content 20%, pH value 7.
The invention also discloses a kind of preparation method of the super high strength high performance fiber concrete of C180 strength grades, including
Following steps：
1) 10 parts of exciting agents of mass fraction and 2.7 parts of defoamers are dissolved in 25% water of total Water, is designated as the aqueous solution
1,15 parts of water reducers, 43 parts of hydroxyl modification carbon nano tube dispersion liquids and 45 parts of graphene oxide dispersions are added to 50% water
In solution, the aqueous solution 2 is designated as；
2) it is 8 in mass ratio to weigh 770 parts:River sand and quartz sand, the 1000 parts of rubbles and 1.7 parts of cellulose fibers of 2 configurations
Dimension is added sequentially in mixer, uniform stirring 2-3min；
3) 505 parts of cement, 70 parts of flyash, 78 parts of rice hull ash, 118 parts of silicon ashes then, are sequentially added, then by step 1)
The aqueous solution 1 of preparation is added in mixer, uniform stirring 2-3min；
4) then to the aqueous solution 2 added in mixer in step 1), uniform stirring 3-4min；
5) mobility of mixture is finally observed, continuously adds the water of total Water remaining 25%, uniform stirring 3-5min,
Discharging, that is, obtain prepared concrete mix；And it is molded, conserves.
Concrete uses steam curing in described preparation method, and its shaping is as follows with maintenance process：
Concrete batching system is poured into cast iron die shaping, jolt ramming, temperature be 20 DEG C ± 2 DEG C, relative humidity >=
1d is stood in 95% standard curing room, form removal, concrete is moved in High Temperature Curing equipment, (programming rate is for heating heating
10 DEG C per hour) to 90 DEG C, thermostatic curing 2d, after cooling (cooling rate is 10 DEG C per hour) to room temperature, in standard curing room
Pond (being saturated limewater solution in pond, solution temperature is 20 DEG C ± 2 DEG C) in maintenance to required age.
The present invention first using cellulose fibre, rice hull ash, modified carbon nano-tube, graphene oxide, cement, flyash,
Quartz sand, river sand, rubble, chemical admixture (including water reducer, exciting agent, defoamer), water, which are prepared for one kind, has high volume
Stability, high tenacity, high-durability C180 strength grades super high strength high performance fiber concrete, overcome normal concrete
The deficiencies of fragility is big, easy to crack, poor durability.
The beneficial effects of the invention are as follows：
1) cellulose fibre used in the present invention has natural hydrophily and high-elastic model point, can effectively suppress mixed
The formation and development of the microcracks caused by factor such as solidifying native plastic shrinkage, drying shrinkage, temperature change；Cellulose fiber surface has very
Strong bond stress, there is good cementitiousness with cement matrix, prevent spike protein gene in concrete cracking, prevent crack
Further development, and the fracture of fiber can increase the energy dissipation capacity of concrete；In addition, cellulose fibre has unique fiber
Cavity structure and huge specific surface area, its cavity structure can store partial moisture, play " interior maintenance action ", promote coagulation
The heat evolution velocity of soil.Therefore, it is resistance to can to improve mechanical property and cracking resistance, the impervious and freeze thawing resistance of concrete etc. for cellulose fibre
Long performance.
2) rice hull ash obtained in the present invention by combusting rice hull, grinding contains more than 90% silica, has higher
Pozzolanic activity, the particle of rice hull ash is tiny (particle is 5-25 μm), concrete dynamic modulus and net road structure inside rice hull ash particle
Huge specific surface area is made it have, 70m can be reached2/ more than g.Therefore, incorporation rice hull ash can make gelling material particles more
Uniformly, grading is good, can play filling role, increases the cohesiveness of concrete；It is secondly as substantial amounts of inside rice hull ash
Microcellular structure can water storage, play " interior maintenance action "；Further, since rice hull ash has the pozzolanic activity similar to silicon ash,
The Ca (OH) in partially or completely silicon ash, with concrete system can be replaced2The fine and close hard aquation sulphur aluminic acid of reaction generation
Calcium, improve concrete flexural strength, compression strength, tensile splitting strength, endurance quality；Finally, rice hull ash is as agricultural residue,
Construction material replacing partial cement is used as after being processed to, can be reduced because rice husk burns and the CO in cement production process2Row
High-volume, and then concrete cost is reduced, realizes the recycling of agricultural wastes, reach the purpose of energy-conserving and environment-protective.
3) present invention is disperseed and is ultrasonically treated to multi-walled carbon nanotube using surfactant, is not cutting off carbon nanometer
Pipe and do not destroy on the basis of its surface texture, obtain can in water stable dispersion modified multiwalled carbon nanotube dispersion liquid.
Due to the nanometer size effect and skin effect of CNT, bridge linking effect is played as nano-scale fiber, control nanoscale splits
The appearance and development of seam, add intensity of concrete base material etc.；In addition, the micro-packing effect of CNT, can be filled
Most of detrimental voids of inside concrete, increase the compactness of concrete, improve each side such as toughness of concrete, endurance quality
Performance.
4) present invention by add dispersant be prepared for can in cement stable dispersion graphene oxide dispersion.Oxygen
On the one hand graphite alkene plays nano-filled effect, on the other hand the oxygen-containing functional group on its surface can be with hydrolysis product of cement hydrogen
Calcium oxide, entringite, hydrated calcium silicate etc. further react, and change the shape of hydrated cementitious crystalline product, strengthen cement matrix
Toughness, make concrete structure that there is higher anti-folding and compression strength etc., and strengthen the caking property between concrete and shaped steel
Energy.
By adding the rice hull ash with volcano ash effect, physics filing effect and " interior maintenance action ", there is toughness reinforcing to make
With the cellulose fibre with " interior maintenance action ", and modified carbon nano-tube and the oxidation of microfibre filled toughening effect can be played
Graphene etc., collaboration improvement concrete performance between each component, it is configured to a kind of resistance to high intensity, high volume stability, height
The super high strength high performance fiber concrete of the C180 strength grades of long property and higher toughness.
Above-mentioned measure can effectively improve the compression strength of concrete, toughness, deformability, endurance quality etc., and strengthen
Adhesion strength and cooperative transformation ability between concrete and shaped steel.The C180 intensity being prepared by the method for the invention
The superhigh intensity high performance concrete of grade, 28d age cubic compressive strengths reach 188.63MPa, and rupture strength reaches
36.44MPa, split tensile strength reach 15.38MPa, and the adhesion strength between shaped steel reaches 7.68MPa, chloride ion resistance grade
Reach VI grade of (28d unstable state chloride ion transport coefficients DRCM＜ 10 × 10-14m2/s).The present invention has prepared strong with superelevation
Degree, high volume stability, the high-performance fiber concrete of high-durability and high tenacity, its raw material is easy to get, preparation technology is simple,
Meet sustainable development and the application of Modern Green construction material and the requirement promoted, be that a kind of green novel high-performance is fine
Tie up concrete material.
Embodiment
With reference to embodiment, the present invention is described in further detail using embodiment, so that the advantage of the present invention is more easy to
In being readily appreciated by one skilled in the art, but the protection domain being not intended to limit the invention.
The preparation method of the super high strength high performance fiber concrete of C180 strength grades of the present invention, comprises the following steps：
1) 10 parts of exciting agents of mass fraction and 2.7 parts of defoamers are dissolved in 25% water of total Water, is designated as the aqueous solution
1,15 parts of water reducers, 43 parts of hydroxyl modification carbon nano tube dispersion liquids and 45 parts of graphene oxide dispersions are added to 50% water
In solution, the aqueous solution 2 is designated as；
2) it is 8 in mass ratio to weigh 770 parts:River sand and quartz sand, the 1000 parts of rubbles and 1.7 parts of cellulose fibers of 2 configurations
Dimension is added sequentially in mixer, uniform stirring 2-3min；
3) 505 parts of cement, 70 parts of flyash, 78 parts of rice hull ash, 118 parts of silicon ashes then, are sequentially added, then by step 1)
The aqueous solution 1 of preparation is added in mixer, uniform stirring 2-3min；
4) then to the aqueous solution 2 added in mixer in step 1), uniform stirring 3-4min；
5) mobility of mixture is finally observed, continuously adds the water of total Water remaining 25%, uniform stirring 3-5min,
Discharging, that is, obtain prepared concrete mix；And it is molded, conserves.
Concrete uses steam curing in preparation method used, and its shaping is as follows with maintenance process：
Concrete batching system is poured into cast iron die shaping, jolt ramming, temperature be 20 ± 2 DEG C, relative humidity >=
1d is stood in 95% standard curing room, form removal, concrete is moved in High Temperature Curing equipment, (programming rate is for heating heating
10 DEG C per hour) to 90 DEG C, thermostatic curing 2d, after cooling (cooling rate is 10 DEG C per hour) to room temperature, in standard curing room
Pond (being saturated limewater solution in pond, solution temperature is 20 ± 2 DEG C) in maintenance to required age.
Cement used is the 62.5R portland cements of P I, and it is good with poly carboxylic acid series water reducer compatibility.
Fine aggregate used uses mass ratio as 8:The good high grade quartz sand of 2 scleroid river sand and grading, river sand
Modulus of fineness is 2.8-3.2, and dioxide-containing silica is not less than 98% in quartz sand, particle diameter 0.3mm-0.6mm, and density is
2.62g/cm3。
Rubble selection grading used is good, hard, the shaggy basaltic broken stone of densification, by the 5- of continuous size fraction
10mm, 10-16mm rubble are according to 7:3 mass ratio is used in mixed way, and parent rock strength is not less than 250MPa, and maximum particle diameter is not
More than 16mm.
Flyash used uses the high-quality I grade of special fine powdered coal of power plant, and water demand ratio is not more than 95%, and specific surface area should be greater than
600m2/kg。
The mass percent of silica is not less than 93% in silicon ash used, and pozzolanic activity index is more than 95%, averagely
0.1 μm -0.3 μm of particle diameter, specific surface area are more than 15m2/g。
Water reducer used is polycarboxylate high performance water-reducing agent, and solid content 20%, pH value 7-8, water-reducing rate is 30%
More than, 7d, 28d compressive strength rate are not less than 180%.
The defoamer uses U.S.'s Hexion AXILAT DF6352DD defoamers.
Rice hull ash used is to be passed through to burn, using ball mill grinding 30-40min at a temperature of 650-800 DEG C by rice husk
Obtained grey purple powder, its dioxide-containing silica are 93.6%, and particle diameter is 5-25 μm, and specific surface area is more than 70m2/g。
Exciting agent used is Organic-inorganic composite exciting agent, is formed according to the raw material compounding of following mass percent meters：
98% waterglass, 2% triethanolamine；
Wherein, the modulus of water glass solution is 1.2, is by waterglass that industrial sodium hydroxide and commercially available modulus are 3.4
Solution is formulated.
The UF500 cellulose fibres that cellulose fibre used is researched and developed for Burkeye companies of the U.S., length 2-3mm, diameter
For 15-20 μm, tensile strength >=900MPa, modulus of elasticity >=8.5GPa, fracture elongation reaches 10%, proportion 1.1g/
cm3, there is good hydrophily, higher bond stress and acid-proof alkaline.
Hydroxyl modification carbon nano tube dispersion liquid used is by made from following methods：
1) compound concentration is 2.0M sodium hydrate aqueous solution, weighs the hydrogen that 2 parts of multi-walled carbon nanotubes add 100 parts of preparations
In aqueous solution of sodium oxide, 5min is ultrasonically treated；It is high that carbon nano tube dispersion liquid is poured into the stainless steel with politef liner
Reactor is pressed, 180 DEG C of reaction 120min after sealing；Room temperature is cooled to after end (centrifugation rate 2000r/ is centrifuged
Min, centrifugation time 30min), then add deionized water and dilute and wash, removing clear liquid, 2 times repeatedly；It is then ultrasonic again
10min, cleaned after stirring by a diameter of 0.2 μm of vinylidene chloride membrane filtration, gained solid product with deionized water to filter
Liquid pH=7；12h is dried at 40 DEG C in vacuum drying oven, obtains the modification multi-wall carbon nano-tube of the oxygen-containing functional groups such as surface hydroxyl
Pipe.
2) modified multiwalled carbon nanotube, the surface-active of the oxygen-containing functional groups such as the surface hydroxyl prepared in step 1) are weighed
98 parts of 0.5 part of agent, 0.1 part of defoamer and deionized water, surfactant, defoamer and modified carbon nano-tube are distributed to successively
In deionized water, stirring, CNT is set to be soaked completely by aqueous surfactant solution；It is ultrasonically treated 30min；Afterwards to scattered
Liquid carries out centrifugal sedimentation (centrifugation rate 2000r/min, centrifugation time 30min).
3) after centrifugation terminates, supernatant liquid is crossed into 300 mesh filter clothes, obtains carbon nano tube dispersion liquid 1；By bottom precipitation (i.e.
The CNT of reunion) according to step 2) supersound process 60min is carried out again, obtain carbon nano tube dispersion liquid 2, CNT point
Hydroxyl modification multi-walled carbon nanotube uniform and stable can disperse in water in dispersion liquid 1 and 2.
Wherein, the average caliber of multi-walled carbon nanotube is 40-50nm, and length is 10-20 μm, purity >=98%；Surface-active
Agent is Triton X-100, pH=7.0,63 DEG C of cloud point；Defoamer defoams for U.S. Hexion AXILAT DF6352DD
Agent.
Graphene oxide dispersion used is obtained by following methods：
(1) 100 parts of deionized waters are added in 1 part of graphene oxide powder, using ultrasonic machine ultrasonic disperse 30min, are obtained
To finely dispersed graphene oxide dispersion；
(2) 0.1 part of water reducer is added in 50 parts of deionized waters, stirred, then add oxygen prepared by step (1)
Graphite alkene dispersion liquid, using special-purpose stirring machine stir 90s, finally give can be dispersed in cement graphene oxide
Dispersion liquid.
Wherein, graphene oxide used is powdered, purity >=98%, and 10 μm -20 μm of diameter, its surface has substantial amounts of
Oxy radical, there is higher decentralization in water；Water reducer used is polycarboxylate high performance water-reducing agent, and solid content is
20%, pH value 7.
Specific embodiment is given below to further illustrate preparation method of the present invention.
The match ratio of the super high strength high performance fiber concrete of C180 strength grades described in the present embodiment (presses each component quality
Number meter) it is as follows：
505 parts of cement, 70 parts of water, 1000 parts of rubble, 770 parts of fine aggregate, 70 parts of flyash, 78 parts of rice hull ash, silicon ash 118
Part, 15 parts of water reducer, 10 parts of exciting agent, 1.7 parts of cellulose fibre, 43 parts of hydroxyl modification carbon nano tube dispersion liquid, graphite oxide
45 parts of alkene dispersion liquid, 2.7 parts of defoamer.
The performance test results of the super high strength high performance fiber concrete of C180 strength grades described in the present embodiment such as institute of table 2
Show.
The super high strength high performance fiber concrete basic performance of the C180 strength grades of table 1
As can be seen from the above Table 1, the super high strength high performance fiber concrete of C180 strength grades of the present invention is a kind of property
The good concrete of energy, can be used as Modern Green construction material application.
Embodiments of the invention are the foregoing is only, are to combine specific optimal enforcement mode to the further detailed of the present invention
Describe in detail bright, it is impossible to therefore limit the scope of the invention, those skill in the art related utilize present disclosure
With method, or on the premise of not departing from present inventive concept, simple change or replacement are made, should be all considered as the present invention's
In protection domain.The protection domain that protection scope of the present invention should be defined by disclosed claim is defined.
Claims (10)
1. a kind of super high strength high performance fiber concrete of C180 strength grades, it is characterised in that fiber concrete includes following
The raw material of mass fraction：
505 parts of cement, 70 parts of water, 1000 parts of rubble, 770 parts of fine aggregate, 70 parts of flyash, 78 parts of rice hull ash, 118 parts of silicon ash,
15 parts of water reducer, 10 parts of exciting agent, 1.7 parts of cellulose fibre, 43 parts of hydroxyl modification carbon nano tube dispersion liquid, graphene oxide point
45 parts of dispersion liquid, 2.7 parts of defoamer.
2. the super high strength high performance fiber concrete of C180 strength grades according to claim 1, it is characterised in that described
Cement is the 62.5R portland cements of P I, and it is good with poly carboxylic acid series water reducer compatibility；
The fine aggregate uses mass ratio as 8:The good high grade quartz sand of 2 scleroid river sand and grading, river sand fineness
Modulus is 2.8-3.2, and dioxide-containing silica is not less than 98% in quartz sand, particle diameter 0.3-0.6mm, density 2.62g/cm3；
The rubble selection grading is good, hard, the shaggy basaltic broken stone of densification, by 5-10mm, 10- of continuous size fraction
16mm rubble is according to 7:3 mass ratio is used in mixed way, and parent rock strength is not less than 250MPa, and maximum particle diameter is no more than
16mm；
The flyash uses the high-quality I grade of special fine powdered coal of power plant, and water demand ratio is not more than 95%, and specific surface area should be greater than
600m2/kg；
The mass percent of silica is not less than 93% in the silicon ash, and pozzolanic activity index is more than 95%, average grain diameter
0.1-0.3 μm, specific surface area is more than 15m2/g；
The water reducer is polycarboxylate high performance water-reducing agent, solid content 20%, pH value 7-8, water-reducing rate more than 30%,
7d, 28d compressive strength rate are not less than 180%；
The defoamer uses U.S.'s Hexion AXILAT DF6352DD defoamers.
3. the super high strength high performance fiber concrete of C180 strength grades according to claim 1, it is characterised in that described
Rice hull ash be as rice husk at a temperature of 650-800 DEG C by burning, using ball mill grinding 30-40min made from grey pink colour
Powder, its dioxide-containing silica are 93.6%, and particle diameter is 5-25 μm, and specific surface area is more than 70m2/g。
4. the super high strength high performance fiber concrete of C180 strength grades according to claim 1, it is characterised in that described
Exciting agent is Organic-inorganic composite exciting agent, is formed according to the raw material compounding of following mass percent meters：
98% waterglass, 2% triethanolamine；
The modulus of the water glass solution is 1.2, is to be matched somebody with somebody by industrial sodium hydroxide and commercially available modulus for 3.4 water glass solution
System forms.
5. the super high strength high performance fiber concrete of C180 strength grades according to claim 1, it is characterised in that described
Cellulose fibre is UF500 cellulose fibres, length 2-3mm, a diameter of 15-20 μm, tensile strength >=900MPa, springform
Amount >=8.5GPa, fracture elongation reach 10%, proportion 1.1g/cm3。
6. the super high strength high performance fiber concrete of C180 strength grades according to claim 1, it is characterised in that described
Hydroxyl modification carbon nano tube dispersion liquid is by made from following methods：
1) compound concentration is the 2.0M NaOH aqueous solution, weighs the NaOH aqueous solution that 2 parts of multi-walled carbon nanotubes add 100 parts of preparations
In, it is ultrasonically treated 5min；Carbon nano tube dispersion liquid is poured into autoclave, 180 DEG C of reaction 120min after sealing；After be cooled to
Room temperature, centrifuge, add deionized water and dilute and wash, remove clear liquid；Ultrasonic 10min again, stirring, vinylidene chloride filter membrane mistake
Filter, gained solid product are washed to filtrate as neutrality；12h is dried at 40 DEG C, obtains the modification of surface hydroxyl oxygen-containing functional group
Multi-walled carbon nanotube；
2) modified multiwalled carbon nanotube, the surfactant 0.5 of the surface hydroxyl oxygen-containing functional group prepared in step 1) are weighed
Part, 98 parts of 0.1 part of defoamer and deionized water, by surfactant, defoamer and modified carbon nano-tube be distributed to successively from
In sub- water, stirring, CNT is set to be soaked completely by aqueous surfactant solution；It is ultrasonically treated 30min；Dispersion liquid is entered afterwards
Row centrifugal sedimentation；
3) supernatant liquid is crossed into 300 mesh filter clothes, obtains carbon nano tube dispersion liquid 1；By bottom precipitation reunite CNT according to
Step 2) carries out ultrasonic 60min again, obtains carbon nano tube dispersion liquid 2, the more walls of hydroxyl modification in carbon nano tube dispersion liquid 1 and 2
CNT uniform and stable can disperse in water.
7. the super high strength high performance fiber concrete of C180 strength grades according to claim 6, it is characterised in that described
The average caliber of multi-walled carbon nanotube is 40-50nm, and length is 10-20 μm, purity >=98%；
The surfactant is Triton X-100, pH=7.0,63 DEG C of cloud point；
The defoamer is U.S.'s Hexion AXILAT DF6352DD defoamers.
8. the super high strength high performance fiber concrete of C180 strength grades according to claim 1, it is characterised in that described
Graphene oxide dispersion is obtained by following methods：
(1) 100 parts of deionized waters are added in 1 part of graphene oxide powder, using ultrasonic machine ultrasonic disperse 30min, are divided
Dissipate uniform graphene oxide dispersion；
(2) 0.1 part of water reducer is added in 50 parts of deionized waters, stirred, then add oxidation stone prepared by step (1)
Black alkene dispersion liquid, 90s is stirred, obtains graphene oxide dispersion；
The graphene oxide is powdered, purity >=98%, and 10 μm -20 μm of diameter, its surface has substantial amounts of oxy radical,
There is higher decentralization in water；
The water reducer is polycarboxylate high performance water-reducing agent, solid content 20%, pH value 7.
9. a kind of preparation method of the super high strength high performance fiber concrete of C180 strength grades, it is characterised in that including as follows
Step：
1) 10 parts of exciting agents of mass fraction and 2.7 parts of defoamers are dissolved in 25% water of total Water, is designated as the aqueous solution 1, will
15 parts of water reducers, 43 parts of hydroxyl modification carbon nano tube dispersion liquids and 45 parts of graphene oxide dispersions are added to 50% aqueous solution
In, it is designated as the aqueous solution 2；
2) it is 8 in mass ratio to weigh 770 parts:2 configuration river sand and quartz sands, 1000 parts of rubbles and 1.7 parts of cellulose fibres according to
It is secondary to be added in mixer, uniform stirring 2-3min；
3) 505 parts of cement, 70 parts of flyash, 78 parts of rice hull ash, 118 parts of silicon ashes then, are sequentially added, then will be prepared in step 1)
The aqueous solution 1 be added in mixer, uniform stirring 2-3min；
4) then to the aqueous solution 2 added in mixer in step 1), uniform stirring 3-4min；
5) mobility of mixture is finally observed, the water of total Water remaining 25% is continuously added, uniform stirring 3-5min, goes out
Material, that is, obtain prepared concrete mix；And it is molded, conserves.
A kind of 10. blanks and moulding and conserving method of the super high strength high performance fiber concrete of C180 strength grades, it is characterised in that use
Steam curing method, comprises the steps：
Concrete batching system is poured into cast iron die shaping, jolt ramming, temperature be 20 ± 2 DEG C, relative humidity >=95%
1d is stood in standard curing room, form removal, concrete is moved in High Temperature Curing equipment, is heated to 10 DEG C of programming rates per hour
It is 90 DEG C, thermostatic curing 2d, molten in the saturated limewater of standard curing room after being cooled to room temperature with programming rate same speed
Liquid, solution temperature are to be conserved in 20 ± 2 DEG C of ponds to required age.
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP3744699A1 (en) * | 2019-05-28 | 2020-12-02 | Sika Technology Ag | Strength enhancer for concretes based on functionalized nanomaterials |
| CN112521043A (en) * | 2020-12-15 | 2021-03-19 | 温州鼎玛建筑技术有限公司 | Concrete modified water reducing agent and preparation method thereof |
| CN113233832A (en) * | 2020-09-23 | 2021-08-10 | 西安建筑科技大学 | High-toughness high-cohesiveness C180-strength ultrahigh-strength fiber concrete and preparation method thereof |
| CN113636811A (en) * | 2021-08-10 | 2021-11-12 | 成都精准混凝土有限公司 | Concrete for 3D printing and preparation method thereof |
| CN115448663A (en) * | 2022-09-14 | 2022-12-09 | 广州大学 | Graphene oxide and silica fume composite modified concrete and preparation method thereof |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1843904A (en) * | 2006-03-30 | 2006-10-11 | 复旦大学 | Method for conducting modification of surface hydroxy group of carbon nanotube |
| CN104030634A (en) * | 2014-06-12 | 2014-09-10 | 杭州固华复合材料科技有限公司 | High-strength and high-toughness reactive powder concrete of carbon doped nano-tube and preparation method of high-strength and high-toughness reactive powder concrete |
| CN106396555A (en) * | 2016-09-08 | 2017-02-15 | 东南大学 | Cellulose fiber internal curing-based ultra-high-performance cement-based composite material and preparation method thereof |
| CN106431137A (en) * | 2016-09-21 | 2017-02-22 | 太原理工大学 | Grapheme concrete and preparation method thereof |
-
2017
- 2017-08-16 CN CN201710703018.1A patent/CN107352913B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1843904A (en) * | 2006-03-30 | 2006-10-11 | 复旦大学 | Method for conducting modification of surface hydroxy group of carbon nanotube |
| CN104030634A (en) * | 2014-06-12 | 2014-09-10 | 杭州固华复合材料科技有限公司 | High-strength and high-toughness reactive powder concrete of carbon doped nano-tube and preparation method of high-strength and high-toughness reactive powder concrete |
| CN106396555A (en) * | 2016-09-08 | 2017-02-15 | 东南大学 | Cellulose fiber internal curing-based ultra-high-performance cement-based composite material and preparation method thereof |
| CN106431137A (en) * | 2016-09-21 | 2017-02-22 | 太原理工大学 | Grapheme concrete and preparation method thereof |
Non-Patent Citations (1)
| Title |
|---|
| 中华人民共和国***: "《中华人民共和国国家标准-普通混凝土力学性能试验方法标准GB/T50081-2002》", 30 April 2003, 中国建筑工业出版社 * |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP3744699A1 (en) * | 2019-05-28 | 2020-12-02 | Sika Technology Ag | Strength enhancer for concretes based on functionalized nanomaterials |
| WO2020239919A1 (en) * | 2019-05-28 | 2020-12-03 | Sika Technology Ag | Strength enhancer for concretes based on functionalized nanomaterials |
| US11884601B2 (en) | 2019-05-28 | 2024-01-30 | Sika Technology Ag | Strength enhancer for concretes based on functionalized nanomaterials |
| CN113233832A (en) * | 2020-09-23 | 2021-08-10 | 西安建筑科技大学 | High-toughness high-cohesiveness C180-strength ultrahigh-strength fiber concrete and preparation method thereof |
| CN112521043A (en) * | 2020-12-15 | 2021-03-19 | 温州鼎玛建筑技术有限公司 | Concrete modified water reducing agent and preparation method thereof |
| CN112521043B (en) * | 2020-12-15 | 2022-04-19 | 金昌市润为化建有限责任公司 | Concrete modified water reducing agent and preparation method thereof |
| CN113636811A (en) * | 2021-08-10 | 2021-11-12 | 成都精准混凝土有限公司 | Concrete for 3D printing and preparation method thereof |
| CN115448663A (en) * | 2022-09-14 | 2022-12-09 | 广州大学 | Graphene oxide and silica fume composite modified concrete and preparation method thereof |
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