CN112079600A - Self-compacting concrete for pumping - Google Patents
Self-compacting concrete for pumping Download PDFInfo
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- CN112079600A CN112079600A CN201910508489.6A CN201910508489A CN112079600A CN 112079600 A CN112079600 A CN 112079600A CN 201910508489 A CN201910508489 A CN 201910508489A CN 112079600 A CN112079600 A CN 112079600A
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B28/00—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements
- C04B28/02—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements containing hydraulic cements other than calcium sulfates
- C04B28/04—Portland cements
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2111/00—Mortars, concrete or artificial stone or mixtures to prepare them, characterised by specific function, property or use
- C04B2111/00034—Physico-chemical characteristics of the mixtures
- C04B2111/00146—Sprayable or pumpable mixtures
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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
- C04B2201/52—High compression strength concretes, i.e. with a compression strength higher than about 55 N/mm2, e.g. reactive powder concrete [RPC]
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Abstract
The invention discloses self-compacting concrete for pumping, which comprises pumping base concrete components and mineral admixture mixed with the pumping base concrete, wherein the mineral admixture accounts for 3-10% of the total weight, the mineral admixture comprises a mixture of oxides and inorganic acid salts at least containing Si, Al, Fe, Ca and S, and the admixture accounts for not more than 0.5% of the total weight. According to the invention, different oxides or inorganic acid salts are combined by mineral admixtures, so that the self-compacting concrete has different activities, surface effects, filling effects or volcanic ash effects, and when the mineral admixtures are doped into the self-compacting concrete, the slump, workability, cohesiveness, segregation resistance and later strength of the self-compacting concrete can be improved, so that the concrete has better fluidity, compactness and homogeneity, and the production requirement of the solid square pile is met; the curing speed and the strength increasing speed of the concrete are promoted, the curing time of the concrete is shortened, and the effect of quick curing in the non-autoclaved process is achieved.
Description
Technical Field
The invention relates to the field of buildings, in particular to self-compacting concrete for pumping.
Background
The self-compacting concrete is a concrete with high fluidity, uniformity and stability and proper viscosity, is not easy to separate, can fill any gap in a template through reinforcing steel bars, is self-compacting under the action of gravity, belongs to a high-performance concrete, and has the outstanding characteristics that a mixture has good working performance, can be uniformly compacted and filled and formed only by dead weight without vibration even under the conditions of intensive reinforcing steel bars and complex shapes, brings great convenience for construction operation, simultaneously has the technologies of improving the quality of the concrete, improving the construction environment, accelerating the construction progress, improving the labor productivity, reducing the engineering cost and the like and has economic effect, and is called as the most revolutionary development of the concrete technology in the last decades.
The operation of the concrete in the production process of the solid square pile is generally manual operation, including stirring, feeding and vibrating of the concrete, which easily causes large errors and ensures the quality. In order to solve the problem, self-compacting concrete can be pumped into the solid square pile die, the traditional manual stirring and feeding work of the concrete is changed into computer control and mechanical pumping operation, the vibrating process is omitted, the construction of the concrete in the solid square pile is controlled in a purely mechanical mode, and the quality superiority and stability of the self-formed pile are guaranteed. Therefore, a self-compacting concrete formula material suitable for producing solid square piles is needed.
Disclosure of Invention
In order to solve the technical problems, the invention provides self-compacting concrete for pumping, which is characterized in that the properties and the self-compacting fluidity of the self-compacting concrete are adjusted by adding a proper mineral admixture, and the strength of the self-compacting concrete achieves the aim of preparing a solid square pile.
The invention provides self-compacting concrete for pumping, which comprises components of pumping base concrete and mineral admixture mixed with the pumping base concrete, wherein the mineral admixture accounts for 3-10% of the total weight, and the mineral admixture comprises a mixture of oxides containing at least Si, Al, Fe and Ca and inorganic acid salt.
The invention provides self-compacting concrete for pumping, which comprises pumping base concrete and mineral admixture, wherein the mineral admixture for adjusting the concrete comprises a mixture containing at least oxides of Si, Al, Fe, Ca and S and inorganic acid salt. The mineral admixtures are combined into different oxides (such as SiO2, Al2O3, FeO, Fe2O3, CaO and the like) or inorganic acid salts (such as silicate, aluminosilicate, sulfate, carbonate and the like) to have different activities, surface effects, filling effects or pozzolana effects, when the mineral admixtures are mixed into the self-compacting concrete, the slump, workability, cohesiveness, segregation resistance and later strength of the self-compacting concrete can be improved, the concrete has better fluidity, compactness and homogeneity, and the production requirement of the solid square piles is met. The mineral admixtures can promote the curing speed and strength growth speed of concrete through mixing synergistic effect, reduce the curing time of the concrete and achieve the effect of quick curing in a non-autoclaved process.
Further, the pumping base concrete comprises the following components in parts by weight: 350 parts of cement, 750 parts of fine aggregate, 850 parts of coarse aggregate, 1300 parts of coarse aggregate, 150 parts of water and 5-10 parts of water reducing agent.
Further, the water reducing agent is one or more of a naphthalene sulfonate water reducing agent, a sulfonated melamine water reducing agent, an aminosulfonate water reducing agent or a polycarboxylic acid water reducing agent; the cement is PII52.5 cement; the fine aggregate is sand with fineness modulus of 2.2-3.7 and mud content of not more than 1%; the coarse aggregate is continuous graded stones with the maximum grain size not larger than 1/3 of the inner diameter of the pumping pipe and the mud content not larger than 1%.
In order to improve the property of the self-compacting concrete, the high-efficiency water reducing agent is adopted, so that the high-efficiency water reducing agent has a strong dispersing effect on one hand, the yield shear stress of a concrete mixture is reduced, and the rheological property of the concrete mixture is improved; on the other hand, the water-cement ratio is effectively reduced, and the mechanical property and durability of the hardened concrete are ensured.
Further, the mineral admixture is a mixture formed by several materials including but not limited to fly ash, slag powder, gypsum powder, steel slag powder, glass beads, metakaolin, zeolite powder, silica fume and limestone powder.
The fly ash is an active gray artificial pozzolanic material discharged after the coal powder of a thermal power plant is combusted in a boiler, and has a surface effect, a filling effect and a pozzolanic activity effect. The surface effect means that the surface of the fly ash can absorb certain ions in the slurry, is beneficial to certain harmful ions in the fly ash solidified concrete and can be used as a crystal nucleus to form hydration products; the filling effect means that the difference of the particle sizes of the fly ash and the cement particles can be filled in the pores of the cement and the aggregate, so that the porosity of the concrete can be reduced, and the compactness of the concrete can be improved; the pozzolanic activity effect means that active Si-O in the fly ash reacts with cement hydration products C-H for the second time to generate C-S-H gel to fill pores of an aggregate-cement slurry interface layer, improve a concrete interface structure and improve strength and durability. The activity of the fly ash is greatly lower than that of cement, so that the slump loss of concrete can be reduced and the impermeability can be improved by replacing the cement. The density of the fly ash is less than that of cement, and after the fly ash replaces the cement in an equivalent manner, the slurry amount in the concrete is increased, the cohesiveness of the concrete is improved, the segregation resistance is improved, and water bleeding is reduced, so that the working performance of the concrete is improved, and the concrete has better fluidity, compactness and uniformity.
The slag powder is a powder material of water-quenched granulated blast furnace slag which is ground to reach the specified fineness, contains more CaO, is mostly amorphous, has a vitreous structure, contains high crystalline energy and has good activity. After the slag powder is mixed into the concrete, the hydration heat of the cement is reduced, the occurrence of a heat peak is delayed, and the early plastic cracks of large-area concrete and the temperature cracks of large-area concrete are greatly reduced. When the slag powder is mixed with the fly ash into concrete, the slump of the concrete is increased due to the superposition effect, the workability is good, the cohesiveness is good, the bleeding is improved, the later strength is increased faster than that of the concrete mixed with the fly ash, and the cost is also obviously reduced.
The gypsum powder comprises natural gypsum powder and desulfurized gypsum powder, and is characterized in that the natural gypsum powder is in continuous gradation, and the desulfurized gypsum powder has narrow particle distribution and is concentrated at 30-60 mu m. In the production process of the concrete, the desulfurized gypsum powder can replace natural gypsum powder and be properly mixed into the concrete, so that the strength, the compactness and the durability of the concrete are improved. The gypsum powder is doped into the concrete, so that alkali excitation and sulfate excitation in the concrete exist simultaneously, the formation of hydrated calcium silicate and hydrated calcium aluminate is promoted, and the hydrated products are filled in the pores, so that the compactness of the concrete structure is increased, the pore structure is optimized, the strength development of the concrete is facilitated, and the durability of the concrete is improved.
The steel slag powder is waste slag produced in the production process of the steel industry, and mainly comes from smelting solvents such as dolomite, iron ore, limestone and the like added in the steel-making process, and impurities separated from two liquid-phase furnace charges which are melted at high temperature and do not melt with each other. The proper amount of the steel slag powder is mixed into the concrete, so that the hydration of the cement can be delayed, the hydration time can be prolonged, and the compressive strength and the crack resistance of the concrete can be improved. The early strength of the concrete doped with the steel slag powder is reduced, and the later strength is improved. The binary complex of the steel slag powder and the fly ash is doped into the concrete, so that the mechanical property and the durability of the concrete can be obviously improved.
The glass beads are spherical glass bodies extracted from the fly ash, and are formed naturally after inorganic minerals are melted and naturally contracted into liquid drops under the action of surface tension of the pulverized coal in the combustion process of a pulverized coal furnace and cooled by high-speed flowing gas, and the pulverized coal has continuous particle size distribution. The glass beads play a role in lubricating balls and bearings in concrete, reduce the friction force among particles and further improve the workability of the concrete. The hydration activity of the glass beads is greater than that of silica fume, the high-activity auxiliary cementing material can promote the hydration heat release process of cement in an early stage, a large amount of C-H is consumed, the polymerization degree of hydration product C-S-H gel silica tetrahedron is increased, and the hardened structure of concrete is more compact and the strength is higher.
Metakaolin is amorphous aluminum silicate formed by low-temperature calcination of superfine kaolin, and has high pozzolanic activity. The metakaolin contains water-aluminium silicate as active component, which reacts with calcium hydroxide precipitated by hydration of cement to produce hydrated calcium-aluminium melilite and secondary C-S-H gel with gel property, and these hydrated products not only enhance the compression resistance, bending resistance and splitting tensile strength of concrete, but also increase the bending resistance toughness of fibre concrete. The late strength of these products, which are formed by the hydration of metakaolin, is still increasing, even comparable to the reinforcing effect of silica fume. The addition of metakaolin does not affect the workability and the fluidity of concrete, and under the condition of the same addition amount and the same slump, the concrete added with metakaolin has smaller viscosity than that added with silica fume, the surface is easy to be smoothed, and the high-efficiency water reducing agent can be saved by 25 percent compared with the latter. Meanwhile, the fluidity of the concrete doped with the metakaolin and the fly ash is obviously increased compared with that of the concrete doped with the metakaolin and the fly ash singly. When the metakaolin mixing amount reaches 20% of the cement amount, the alkali-aggregate reaction can be effectively inhibited.
The zeolite powder is a volcanic ash material formed by grinding natural zeolite rocks, contains a large amount of active SiO2 and Al2O3, and can react with Ca (OH)2 separated out by cement hydration for secondary hydration reaction under the excitation of alkaline condition to generate hydrated calcium silicate gel, such as hydrated calcium silicate gel and hydrated calcium aluminate gel, so as to promote the cement hydration reaction; on the other hand, because the zeolite has a grid structure, the interior of the zeolite is filled with uniformly-sized cavities and channels, and the zeolite has large openness, is ground to have a large specific surface area, can adsorb a large amount of water molecules and gases in a natural state, and is in equilibrium with the relative humidity of the atmosphere. When the additive is mixed into concrete, the excessive mixing water in the concrete can be absorbed, the bleeding property of the concrete is overcome, the stored gas is released into the concrete mixture, the concrete viscosity and the slurry wrapping amount of aggregate are improved, the cohesiveness of the concrete mixture is improved, and the overall workability is improved. The zeolite powder can replace part of fly ash, and the strength of the concrete is improved.
The silicon ash, also called as silica fume, is produced by using iron alloy to smelt ferrosilicon and industrial silicon (metal silicon) and by using a large amount of highly volatile SiO2 and Si gas produced in an ore-smelting electric furnace, and the gas is discharged and then quickly oxidized, condensed and precipitated with air. The silica fume is doped into the concrete, so that the compression resistance, the bending resistance, the permeability resistance, the corrosion resistance, the impact resistance and the wear resistance of the concrete can be obviously improved; the concrete has the functions of retaining water, preventing segregation and bleeding and greatly reducing the pumping resistance of the concrete; the service life of the concrete is obviously prolonged, and the durability of the concrete can be improved by one time or even several times especially under severe environments of chloride pollution corrosion, sulfate corrosion, high humidity and the like. The silica fume has about 5 times of the efficacy of cement, the cost can be reduced, and the durability can be improved; effectively preventing the concrete alkali aggregate reaction. The silica fume has extremely strong volcanic ash effect, and can perform secondary hydration reaction with cement hydration products Ca (OH)2 when being mixed with concrete to form a gelled product, fill a cement stone structure, improve the microstructure of slurry and improve the mechanical property and durability of a hardened body; the silica fume is an amorphous spherical particle, and can improve the rheological property of the concrete. The average particle size of the silica fume is smaller, so that the silica fume has good filling effect, can be filled in gaps among cement particles, and improves the strength and durability of concrete.
The main component of the limestone powder is CaCO3 with small fineness, which can not only fill concrete to supplement fine particles, but also increase the ratio of the specific surface area of solid to the volume of water, thereby reducing bleeding and segregation. The limestone powder has certain activity, can replace part of cement and fly ash in concrete, and forms soft slurry with the cement and water, so that the slurry amount of the concrete is increased, and the workability and the rheological property of the concrete are improved. The limestone powder has a crystal nucleus effect, promotes the hydration reaction of C3S, C3A and C4AF to generate the carbonate aluminate, and is beneficial to the development of the early strength of the concrete; and the composite can also be used as a nucleation matrix of hydrated calcium silicate C-S-H, so that nucleation barrier is reduced, and cement hydration is accelerated.
Further, the mineral admixture comprises the following components in parts by weight: 45-80 parts of fly ash, 22-40 parts of slag powder and 2-15 parts of gypsum powder.
The fly ash, the slag powder and the gypsum powder are mixed into the basic concrete, and the fly ash and the slag powder are used in a matching way, so that the stacking effect is achieved, the slump and the workability of the concrete are improved, the self-compacting concrete has better cohesiveness and good self-compacting effect, and the later strength is increased faster than that of the basic concrete. And then gypsum powder is doped, and the fly ash and the slag powder are matched to ensure that alkali excitation and sulfate excitation in the concrete exist simultaneously, so that the formation of hydrated calcium silicate and hydrated calcium aluminate is promoted, and the hydrated products are filled in the pores, so that the compactness of the concrete structure is increased, the pore structure is optimized, the strength development of the concrete is facilitated, and the durability of the concrete is improved. The addition of the fly ash, the slag powder and the gypsum powder promotes the curing speed and the strength increasing speed of the concrete, reduces the curing time of the concrete and achieves the effect of quick curing without an autoclave process.
Further, the mineral admixture also comprises one or more of 12-45 parts of limestone powder, 8-20 parts of silica fume, 2-8 parts of metakaolin and 20-45 parts of glass beads.
In addition, limestone powder is doped into the concrete, the workability and rheological property of the concrete are improved under the synergistic effect of the limestone powder and the fly ash, and the limestone powder is used in combination with the gypsum powder to improve the early strength of the concrete, improve the later strength increasing speed of the gypsum powder and jointly improve the overall strength of the concrete. The silica fume is doped into the concrete, so that the compression resistance, wear resistance, corrosion resistance and other properties of the concrete are improved, the mechanical property and durability of the hardened concrete are improved under the synergistic effect of the silica fume and the fly ash, and the rheological property is improved. The synergistic effect of metakaolin and fly ash can improve the early-stage fluidity and the later-stage strength of the concrete. The glass beads are doped into the concrete to play a role in lubricating balls and bearings, so that the friction force among particles is reduced, and the workability of the concrete is improved; the method promotes the hydration heat release process of cement in an early stage, consumes a large amount of C-H, increases the polymerization degree of hydration products C-S-H gel silicon-oxygen tetrahedrons, and ensures that a concrete hardened structure is more compact and has higher strength.
Further, the mineral admixture comprises, by weight, 35-60 parts of fly ash, 15-30 parts of slag powder, 5-20 parts of steel slag powder, 1-5 parts of metakaolin and 3-15 parts of zeolite powder.
Further, the mineral admixture comprises, by weight, 35-55 parts of fly ash, 15-35 parts of slag powder, 12-25 parts of glass beads, 2-8 parts of metakaolin and 3-15 parts of zeolite powder.
Further, the mineral admixture comprises, by weight, 35-63 parts of fly ash, 18-45 parts of slag powder, 2-15 parts of gypsum powder, 12-20 parts of glass beads, 1-5 parts of metakaolin and 3-15 parts of zeolite powder.
The self-compacting concrete for pumping provided by the invention adjusts the property and the self-compacting fluidity of the self-compacting concrete by doping mineral admixtures with different materials and different contents, enhances the rheological property of the concrete admixture, greatly reduces the hydration heat of the admixture, reduces the temperature rise of the concrete, and reduces the cracking caused by temperature stress, so as to adapt to the production of different raw materials and different environments and the requirement of square pile strength of different underground environments.
Further, the concrete admixture further comprises an additive accounting for not more than 0.5 percent of the total weight, wherein the additive adopts one or more of but not limited to an early strength agent, a retarder, an air entraining agent, a shrinkage reducing agent, a thickening agent, an expanding agent, a collapse preventing agent and a defoaming agent.
The self-compacting concrete for pumping provided by the invention needs to be added with additives in order to adjust proper initial state, initial strength, later strength and the like. If the early strength agent is added, the hydration speed of the cement is promoted, and the early strength of the concrete is improved; adding a retarder to ensure the actual construction time; adding an air entraining agent to improve the rheological property and frost resistance of the mixture; a shrinkage reducing agent is added to improve the volume stability of the concrete in the hardening process; adding a thickening agent to improve the segregation resistance of the concrete mixture; the expansion agent is added to compensate the shrinkage of the concrete, so that the possibility of cracking of the concrete is reduced; the collapse preventing agent is added to delay cement hydration and coagulation, maintain concrete slump, and the defoaming agent is added to control the generation of foam in the concrete system and improve the compactness and the attractiveness of the concrete. The combination and the multifunctional superposition of multiple components can improve the comprehensive properties of the self-compacting concrete.
Detailed Description
The technical solutions of the present invention will be described clearly and completely with reference to the following embodiments of the present invention, and it should be understood that the described embodiments are only a part of the embodiments of the present invention, and not all of the 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
The embodiment provides self-compacting concrete for pumping, which comprises components of pumping base concrete, mineral admixture mixed with the pumping base concrete and additive, wherein the volume of 1 cubic meter is 2550 kg.
The pumping foundation concrete comprises the following components in parts by weight: 305 parts of PII52.5 cement, 797 parts of fine aggregate, 1202 parts of coarse aggregate, 125 parts of water and 8.5 parts of naphthalene sulfonate water reducing agent, wherein the fine aggregate is sand with fineness modulus of 2.2-3.7 and mud content of not more than 1%; the coarse aggregate is continuous graded stone with maximum particle size not greater than 1/3 of the inner diameter of the pumping pipe and mud content not greater than 1%.
The mineral admixture accounts for 3-5% of the total weight, and comprises a mixture at least containing oxides of Si, Al, Fe and Ca and inorganic acid salt, and concretely comprises 55 parts of fly ash, 30 parts of slag powder and 12 parts of gypsum powder in parts by weight.
The admixture accounts for 0.4 percent of the total weight and comprises 2 parts of an early strength agent, 2 parts of a retarder, 2 parts of an air entraining agent, 1 part of a thickening agent, 1 part of an expanding agent and 2 parts of a defoaming agent.
Example 2
The embodiment provides self-compacting concrete for pumping, which comprises components of pumping base concrete, mineral admixture mixed with the pumping base concrete and additive, wherein the volume of 1 cubic meter is 2580 kg.
The pumping foundation concrete comprises the following components in parts by weight: 275 parts of PII52.5 cement, 818 parts of fine aggregate, 1165 parts of coarse aggregate, 132 parts of water and 7.2 parts of naphthalene sulfonate water reducing agent, wherein the fine aggregate is sand with fineness modulus of 2.5-3.5 and mud content not more than 1%; the coarse aggregate is continuous graded stone with particle size of 1-2cm and mud content not greater than 1%.
The mineral admixture accounts for 3-5% of the total weight, and comprises a mixture at least containing oxides of Si, Al, Fe and Ca and inorganic acid salt, and concretely comprises, by weight, 50 parts of fly ash, 28 parts of slag powder, 5 parts of gypsum powder, 14 parts of limestone powder, 11 parts of silica fume, 5 parts of metakaolin and 23 parts of glass beads.
The admixture accounts for 0.3 percent of the total weight and comprises 2 parts of an early strength agent, 1.5 parts of a retarder, 1 part of an air entraining agent, 1 part of a collapse preventing agent and 2 parts of a defoaming agent by weight.
Example 3
The embodiment provides self-compacting concrete for pumping, which comprises components of pumping base concrete, mineral admixture mixed with the pumping base concrete and additive, wherein the volume of 1 cubic meter is 2530 kg.
The pumping foundation concrete comprises the following components in parts by weight: the mortar comprises, by weight, 328 parts of PII52.5 cement, 835 parts of fine aggregate, 1235 parts of coarse aggregate, 142 parts of water and 5.6 parts of naphthalene sulfonate water reducing agent, wherein the fine aggregate is sand with fineness modulus of 2.8-3.2 and mud content of not more than 1%; the coarse aggregate is stone with particle size of 1-2cm and mud content not more than 1%.
The mineral admixture accounts for 5-10% of the total weight, and comprises a mixture at least containing oxides of Si, Al, Fe and Ca and inorganic acid salt, and concretely comprises, by weight, 51 parts of fly ash, 20 parts of slag, 13 parts of steel slag powder, 4 parts of metakaolin and 5 parts of zeolite powder.
The additive accounts for 0.3 percent of the total weight and comprises 2 parts of air entraining agent, 1 part of shrinkage reducing agent, 2 parts of thickening agent, 1 part of collapse preventing agent and 2 parts of defoaming agent.
Example 4
The embodiment provides self-compacting concrete for pumping, which comprises components of pumping base concrete, mineral admixture mixed with the pumping base concrete and additive, wherein the volume of 1 cubic meter is 2560 kg.
The pumping foundation concrete comprises the following components in parts by weight: 262 parts of PII52.5 cement, 762 parts of fine aggregate, 1245 parts of coarse aggregate, 112 parts of water and 9.3 parts of naphthalene sulfonate water reducing agent, wherein the fine aggregate is sand with fineness modulus of 2.7-3.0 and mud content of not more than 1%; the coarse aggregate is continuous graded stone with maximum particle size not greater than 1/3 of the inner diameter of the pumping pipe and mud content not greater than 1%.
The mineral admixture accounts for 3-5% of the total weight, and comprises a mixture at least containing oxides of Si, Al, Fe and Ca and inorganic acid salt, and concretely comprises 43 parts of fly ash, 28 parts of slag powder, 19 parts of glass beads, 6 parts of metakaolin and 11 parts of zeolite powder by weight.
The admixture accounts for 0.2 percent of the total weight and comprises 1 part of retarder, 2 parts of shrinkage reducing agent, 1 part of air entraining agent and 1 part of defoaming agent in parts by weight.
Example 5
The embodiment provides self-compacting concrete for pumping, which comprises components of pumping base concrete, mineral admixture mixed with the pumping base concrete and additive, wherein the volume of 1 cubic meter is 2550 kg.
The pumping foundation concrete comprises the following components in parts by weight: 52.5 parts of PII cement 343 parts, 781 parts of fine aggregate, 1281 parts of coarse aggregate, 106 parts of water and 6.3 parts of naphthalene sulfonate water reducing agent, wherein the fine aggregate is sand with fineness modulus of 2.3-3.6 and mud content of not more than 1%; the coarse aggregate is continuous graded stone with maximum particle size not greater than 1/3 of the inner diameter of the pumping pipe and mud content not greater than 1%.
The mineral admixture accounts for 3-5% of the total weight, and comprises a mixture at least containing oxides of Si, Al, Fe and Ca and inorganic acid salt, and concretely comprises, by weight, 52 parts of fly ash, 37 parts of slag powder, 9 parts of gypsum powder, 18 parts of glass microspheres, 3 parts of metakaolin and 10 parts of zeolite powder.
The additive accounts for 0.3 percent of the total weight and comprises 1 part of retarder, 1 part of air entraining agent, 2 parts of shrinkage reducing agent, 1 part of thickening agent, 1 part of collapse preventing agent and 2 parts of defoaming agent.
The self-compacting concrete of each example was tested according to the slump flow test method, the V-funnel test method and the L-box test method, and the data in the following table were obtained.
TABLE 1 working Performance Table of self-compacting concrete
Table 2 shows the mechanical properties of the self-compacting concrete
| Mechanical properties | Example 1 | Example 2 | Example 3 | Example 4 | Example 5 |
| 7d compressive Strength (MPa) | 45.1 | 46.2 | 48.0 | 47.6 | 48.8 |
| 28d compressive Strength (MPa) | 58.4 | 59.2 | 60.1 | 60.6 | 61.0 |
| Modulus of elasticity (MPa) of 28d | 4.6×104 | 4.8×104 | 4.6×104 | 4.7×104 | 4.9×104 |
| 14d limiting expansion ratio | 3.1×10-4 | 3.0×10-4 | 3.1×10-4 | 3.0×10-4 | 3.0×10-4 |
From the data in tables 1 and 2 above, the self-compacting concrete of the present invention has the following characteristics:
1. the method can ensure sufficient compensation shrinkage on the premise of meeting the normal working performance, and achieves the purpose of synthesizing the component without steam pressure;
2. the pouring is easy, the construction efficiency is high, the production efficiency is improved, and the cost is reduced;
3. the construction environment is improved, and the noise pollution is reduced;
4. the solid square pile manufactured by pumping has high strength and strong compressive resistance.
Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment includes only a single embodiment, and such description is for clarity only, and all embodiments may be combined with each other, or some embodiments may be combined with existing conventional techniques to form other embodiments as will be apparent to those skilled in the art without inventive faculty.
Claims (10)
1. A self-compacting concrete for pumping, characterized in that: the concrete comprises pumping base concrete components and mineral admixture mixed with the pumping base concrete, wherein the mineral admixture accounts for 3-10% of the total weight, the mineral admixture comprises a mixture of oxides and inorganic acid salts at least containing Si, Al, Fe, Ca and S, and the mineral admixture also comprises an additive accounting for not more than 0.5% of the total weight.
2. Self-compacting concrete for pumping according to claim 1, characterized in that: the pumping foundation concrete comprises the following components in parts by weight: 350 parts of cement, 750 parts of fine aggregate, 850 parts of coarse aggregate, 1300 parts of coarse aggregate, 150 parts of water and 5-10 parts of water reducing agent.
3. Self-compacting concrete for pumping according to claim 2, characterized in that: the water reducing agent is one or more of a naphthalene sulfonate water reducing agent, a sulfonated melamine water reducing agent, an aminosulfonate water reducing agent or a polycarboxylic acid water reducing agent; the cement is PII52.5 cement; the fine aggregate is sand with fineness modulus of 2.2-3.7 and mud content of not more than 1%; the coarse aggregate is continuous graded stones with the maximum grain size not larger than 1/3 of the inner diameter of the pumping pipe and the mud content not larger than 1%.
4. Self-compacting concrete for pumping according to claim 1, characterized in that: the mineral admixture is a mixture formed by a plurality of materials including but not limited to fly ash, slag powder, gypsum powder, steel slag powder, glass microspheres, metakaolin, zeolite powder, silica fume and limestone powder.
5. Self-compacting concrete for pumping according to claim 4, characterized in that: the mineral admixture comprises the following components in parts by weight: 45-80 parts of fly ash, 22-40 parts of slag powder and 2-15 parts of gypsum powder.
6. Self-compacting concrete for pumping according to claim 5, characterized in that: the mineral admixture also comprises one or more of 12-45 parts of limestone powder, 8-20 parts of silica fume, 2-8 parts of metakaolin and 20-45 parts of glass beads.
7. Self-compacting concrete for pumping according to claim 4, characterized in that: the mineral admixture comprises, by weight, 35-60 parts of fly ash, 15-30 parts of slag powder, 5-20 parts of steel slag powder, 1-5 parts of metakaolin and 3-15 parts of zeolite powder.
8. Self-compacting concrete for pumping according to claim 4, characterized in that: the mineral admixture comprises, by weight, 35-55 parts of fly ash, 15-35 parts of slag powder, 12-25 parts of glass beads, 2-8 parts of metakaolin and 3-15 parts of zeolite powder.
9. Self-compacting concrete for pumping according to claim 4, characterized in that: the mineral admixture comprises, by weight, 35-63 parts of fly ash, 18-45 parts of slag powder, 2-15 parts of gypsum powder, 12-20 parts of glass beads, 1-5 parts of metakaolin and 3-15 parts of zeolite powder.
10. Self-compacting concrete for pumping according to claim 1, characterized in that: the admixture adopts one or more of but not limited to an early strength agent, a retarder, an air entraining agent, a shrinkage reducing agent, a thickening agent, an expanding agent, a collapse preventing agent and a defoaming agent.
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113929386A (en) * | 2021-10-20 | 2022-01-14 | 厦门智欣建工科技有限公司 | Formula and preparation method of steam-curing-free self-compacting concrete for prefabricated part |
| CN114455892A (en) * | 2022-01-26 | 2022-05-10 | 江苏中砼新材料科技有限公司 | Light self-compacting high-performance concrete and preparation process thereof |
| CN114751670A (en) * | 2022-04-27 | 2022-07-15 | 湖南高翔新材料有限公司 | High-performance concrete admixture and preparation method thereof |
| CN115947566A (en) * | 2023-03-11 | 2023-04-11 | 石家庄市长安育才建材有限公司 | Additive for steam curing-free precast concrete and preparation method thereof |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102060482A (en) * | 2010-11-15 | 2011-05-18 | 北京新奥混凝土集团有限公司 | Self-compacting concrete |
-
2019
- 2019-06-13 CN CN201910508489.6A patent/CN112079600A/en active Pending
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102060482A (en) * | 2010-11-15 | 2011-05-18 | 北京新奥混凝土集团有限公司 | Self-compacting concrete |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113929386A (en) * | 2021-10-20 | 2022-01-14 | 厦门智欣建工科技有限公司 | Formula and preparation method of steam-curing-free self-compacting concrete for prefabricated part |
| CN114455892A (en) * | 2022-01-26 | 2022-05-10 | 江苏中砼新材料科技有限公司 | Light self-compacting high-performance concrete and preparation process thereof |
| CN114751670A (en) * | 2022-04-27 | 2022-07-15 | 湖南高翔新材料有限公司 | High-performance concrete admixture and preparation method thereof |
| CN115947566A (en) * | 2023-03-11 | 2023-04-11 | 石家庄市长安育才建材有限公司 | Additive for steam curing-free precast concrete and preparation method thereof |
| CN115947566B (en) * | 2023-03-11 | 2023-08-08 | 石家庄市长安育才建材有限公司 | Additive for steam curing-free precast concrete and preparation method thereof |
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