Self-compacting concrete viscosity reducer and preparation method, use method and application thereof

Abstract

The present invention provides a self-compacting concrete viscosity reducer and a preparation method, a use method, and an application thereof, which relates to the technical field of concrete admixtures, and includes material A and material B; wherein material A includes the following components: saponin powder, glass microspheres, ultrafine limestone powder, and calcium stearate; material B includes the following components: sodium tripolyphosphate, sodium thiosulfate, a rheological agent, and water. The present invention solves the technical problem that self-compacting concrete of strength grade C100 and above cannot be pumped for construction due to high viscosity, and achieves the technical effect that the slump retention performance, homogeneity, and mechanical properties of the self-compacting concrete are simultaneously improved by the coordinated cooperation of the various components.

Description

Technical Field

[0001] The present invention relates to the technical field of concrete admixtures, and in particular to a self-compacting concrete viscosity reducer and a preparation method, a use method and an application thereof. Background Art

[0002] With the continuous improvement of construction technology, ordinary concrete can no longer meet the needs of high-rise, super-high-rise, super-large span, irregular structure and complex engineering. In order to achieve the functional requirements of the structure under specific environment, high-strength self-compacting concrete is increasingly widely used. Therefore, high-strength and ultra-high-strength concrete has become one of the current development trends of concrete technology.

[0003] At present, in order to achieve high or ultra-high strength, a large amount of cementitious materials and a lower water consumption are often used. The water-cement ratio is greatly reduced, resulting in a high slurry consistency and high concrete viscosity, causing problems such as slow concrete flow and difficulty in pumping, and even causing dangerous accidents such as pipe blockage and pipe burst, seriously affecting construction safety.

[0004] There is currently no effective method for reducing the viscosity of ultra-high-strength concrete. The viscosity-reducing polycarboxylic acid water-reducing agent, the addition of mineral admixtures, and the reasonable selection of sand ratio proposed in the prior art do not have a significant viscosity-reducing effect. Therefore, how to effectively solve the viscosity reduction problem of ultra-high-strength concrete is still one of the construction problems.

[0005] In view of this, the present invention is proposed. Summary of the invention

[0006] One of the purposes of the present invention is to provide a self-compacting concrete viscosity reducer, which is suitable for self-compacting concrete with a strength grade of C100 and above, can significantly reduce the viscosity of the self-compacting concrete, can improve the rheological properties of the self-compacting concrete, and can effectively improve the homogeneity and mechanical properties of the self-compacting concrete.

[0007] The second object of the present invention is to provide a method for preparing a self-compacting concrete viscosity reducer, which has a simple process, high efficiency and is suitable for factory production.

[0008] The third object of the present invention is to provide a method for using a self-compacting concrete viscosity reducer, which can significantly reduce the viscosity of self-compacting concrete with strength grades of C100 and above, and can effectively improve the construction performance of self-compacting concrete with strength grades of C100 and above.

[0009] The fourth object of the present invention is to provide an application of a self-compacting concrete viscosity reducer, which has good concrete construction effect and quality and achieves outstanding application effect.

[0010] In order to achieve the above-mentioned purpose of the present invention, the following technical solutions are particularly adopted:

[0011] In a first aspect, a self-compacting concrete viscosity reducer includes material A and material B;

[0012] The A material comprises the following components:

[0013] Gleditsia sinensis powder, glass microspheres, ultrafine limestone powder, and calcium stearate;

[0014] The B material includes the following components:

[0015] Sodium tripolyphosphate, sodium thiosulfate, rheological agent, and water.

[0016] Furthermore, the material A includes the following components by mass:

[0017] 20-30 parts of saponin powder, 40-50 parts of glass microspheres, 10-15 parts of ultrafine limestone powder, and 15-20 parts of calcium stearate.

[0018] Furthermore, the specific surface area of ​​the soapberry powder is 350 m 2 / kg or more;

[0019] The density of the glass microspheres is 2.2 g / cm 3 , with a specific surface area of ​​3250~3400m 2 / kg;

[0020] The specific surface area of ​​the ultrafine limestone powder is 400-450m 2 / kg.

[0021] Furthermore, the B material includes the following components by mass:

[0022] 10-20 parts of sodium tripolyphosphate, 10-15 parts of sodium thiosulfate, 20-30 parts of rheological agent, and 44-54 parts of water.

[0023] Furthermore, the material A includes the following components by mass:

[0024] 25-30 parts of sapodilla powder, 40-50 parts of glass microspheres, 10-13 parts of ultrafine limestone powder, and 16-19 parts of calcium stearate;

[0025] The B material includes the following components by mass:

[0026] 15-20 parts of sodium tripolyphosphate, 10-13 parts of sodium thiosulfate, 25-30 parts of rheological agent, and 44-50 parts of water.

[0027] In a second aspect, a method for preparing the self-compacting concrete viscosity reducer as described in any one of the above items comprises the following steps:

[0028] The components are mixed to obtain material A;

[0029] The components are mixed to obtain material B.

[0030] In a third aspect, a method for using the self-compacting concrete viscosity reducer as described in any one of the above items comprises the following steps:

[0031] When mixing self-compacting concrete, first add material A and mix, then add material B and other admixtures and mix.

[0032] Furthermore, the self-compacting concrete includes self-compacting concrete with a strength grade of C100 and above.

[0033] Furthermore, the amount of material A added is 4-6% of the mass of cement;

[0034] The added amount of the B material is 0.8-1.4% of the cement mass.

[0035] A fourth aspect is a use of the self-compacting concrete viscosity reducer described in any one of the above items in concrete construction.

[0036] Compared with the prior art, the present invention has at least the following beneficial effects:

[0037] The self-compacting concrete viscosity reducer provided by the present invention is suitable for self-compacting concrete with a strength grade of C100 or above. Specifically, the saponin powder in material A contains a large amount of natural tea saponin, which contains a large amount of surfactant, and can introduce uniform and tiny bubbles into the self-compacting concrete with a strength grade of C100 or above, thereby reducing the apparent tension of the cement paste, improving the dispersibility, increasing the paste volume, reducing the viscosity of the concrete mixture, and improving the flowability of the self-compacting concrete with a strength grade of C100 or above. The glass microspheres in material A are a new type of natural tea saponin extracted from fly ash. As a building material, the particles are spherical and can play a "ball" lubrication role. They have a strong morphological effect. In addition, their low water demand ratio can reduce water. In cement paste, they can effectively reduce viscosity and increase fluidity. The ultrafine limestone powder in material A has low surface energy and low water demand. In self-compacting concrete with strength grade C100 and above, it can reduce the viscosity of concrete. The calcium stearate in material A mainly plays the role of a foam stabilizer. The tiny bubbles produced by saponin powder play a great role in reducing viscosity. Calcium stearate is adsorbed on the surface of cement particles, and some cement particles become As hydrophobic particles, they are adsorbed on the gas-liquid surface of bubbles to prevent them from further growing and merging, and can stabilize the bubbles for a long time. Therefore, saponin powder and calcium stearate work synergistically to entrain and stabilize air. At the same time, glass microspheres and ultrafine limestone powder have a micro-powder effect, which fills the gaps between cement particles, can reduce the porosity of the cementitious system, and improve the strength of concrete. In addition, in material B, sodium tripolyphosphate forms a complex with the calcium ions of ordinary Portland cement, thereby delaying cement hydration, reducing hydration heat, and prolonging the setting time, so that the newly mixed high-strength concrete can be maintained for a longer time. The plasticity between the two can reduce the early viscosity of high-strength concrete; sodium thiosulfate can make up for the insufficient early strength of concrete caused by air entraining agent and retarder, sodium thiosulfate can be quickly dissolved in water, increase the sulfate content in cement clinker, and can react with the hydration product of cement clinker tricalcium aluminate to form calcium sulfonate, reduce early segregation and water bleeding, and can synergize with saponin powder to increase the slurry amount of slurry, and can achieve better wrapping of sandstone aggregate; rheological agent is a polyether polymer, which can improve the rheological properties of ultra-high-strength self-compacting concrete, reduce viscosity, and reduce segregation and water bleeding. In short, the viscosity reducer of the present invention not only achieves the purpose of reducing the viscosity of self-compacting concrete with strength grade C100 and above through the coordinated cooperation of each component, but also achieves the technical effects of good homogeneity, non-stratified segregation and high strength of self-compacting concrete.

[0038] The method for preparing the self-compacting concrete viscosity reducer provided by the invention has simple process, high efficiency and is suitable for factory production.

[0039] The method for using the self-compacting concrete viscosity reducer provided by the present invention can significantly reduce the viscosity of self-compacting concrete of strength grade C100 and above, and can effectively improve the construction performance of self-compacting concrete of strength grade C100 and above, which not only solves the technical problem that concrete is difficult to construct due to its high viscosity, but also enables the concrete to have the advantages of good homogeneity, no stratification and segregation, and high strength.

[0040] The application of the self-compacting concrete viscosity reducer provided by the invention has good concrete construction effect and quality, and has achieved outstanding application effect. DETAILED DESCRIPTION

[0041] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0042] According to a first aspect of the present invention, there is provided a self-compacting concrete viscosity reducer, comprising material A and material B;

[0043] Among them, material A includes the following components:

[0044] Gleditsia sinensis powder, glass microspheres, ultrafine limestone powder, and calcium stearate;

[0045] Among them, material B includes the following components:

[0046] Sodium tripolyphosphate, sodium thiosulfate, rheological agent, and water.

[0047] The self-compacting concrete viscosity reducer provided by the present invention is suitable for self-compacting concrete with a strength grade of C100 or above. Specifically, the saponin powder in material A contains a large amount of natural tea saponin, which contains a large amount of surfactant, and can introduce uniform and tiny bubbles into the self-compacting concrete with a strength grade of C100 or above, thereby reducing the apparent tension of the cement paste, improving the dispersibility, increasing the paste volume, reducing the viscosity of the concrete mixture, and improving the flowability of the self-compacting concrete with a strength grade of C100 or above. The glass microspheres in material A are a new type of natural tea saponin extracted from fly ash. As a building material, the particles are spherical and can play a "ball" lubrication role. They have a strong morphological effect. In addition, their low water demand ratio can reduce water. In cement paste, they can effectively reduce viscosity and increase fluidity. The ultrafine limestone powder in material A has low surface energy and low water demand. In self-compacting concrete with strength grade C100 and above, it can reduce the viscosity of concrete. The calcium stearate in material A mainly plays the role of a foam stabilizer. The tiny bubbles produced by saponin powder play a great role in reducing viscosity. Calcium stearate is adsorbed on the surface of cement particles, and some cement particles become As hydrophobic particles, they are adsorbed on the gas-liquid surface of bubbles to prevent them from further growing and merging, and can stabilize the bubbles for a long time. Therefore, saponin powder and calcium stearate work synergistically to entrain and stabilize air. At the same time, glass microspheres and ultrafine limestone powder have a micro-powder effect, which fills the gaps between cement particles, can reduce the porosity of the cementitious system, and improve the strength of concrete. In addition, in material B, sodium tripolyphosphate forms a complex with the calcium ions of ordinary Portland cement, thereby delaying cement hydration, reducing hydration heat, and prolonging the setting time, so that the newly mixed high-strength concrete can be maintained for a longer time. The plasticity between the two materials can reduce the early viscosity of high-strength concrete; sodium thiosulfate can make up for the insufficient early strength of concrete caused by air-entraining agents and retarders. Sodium thiosulfate can be quickly dissolved in water, increase the sulfate content in cement clinker, and react with the hydration product of tricalcium aluminate in cement clinker to form calcium aluminate, reducing early segregation and bleeding. At the same time, it can synergize with saponin powder to increase the slurry volume and achieve better wrapping of sand and gravel aggregates; the rheological agent is a polyether macromolecular polymer that can improve the rheological properties of ultra-high-strength self-compacting concrete, reduce viscosity, and reduce segregation and bleeding.

[0048] In summary, the viscosity reducer of the present invention not only achieves the purpose of reducing the viscosity of self-compacting concrete with strength grade C100 and above through the coordinated cooperation of various components, but also realizes the technical effects of good homogeneity, no stratification and segregation, and high strength of the self-compacting concrete.

[0049] In a preferred embodiment, material A comprises the following components in parts by mass:

[0050] 20-30 parts of saponin powder, 40-50 parts of glass microspheres, 10-15 parts of ultrafine limestone powder, and 15-20 parts of calcium stearate.

[0051] In the present invention, typical but non-limiting mass fractions of soapnut powder can be, for example, 20 parts, 22 parts, 24 parts, 26 parts, 28 parts, and 30 parts; typical but non-limiting mass fractions of glass microspheres can be, for example, 40 parts, 42 parts, 44 parts, 46 parts, 48 ​​parts, and 50 parts; typical but non-limiting mass fractions of ultrafine limestone powder can be, for example, 10 parts, 11 parts, 12 parts, 13 parts, 14 parts, and 15 parts; typical but non-limiting mass fractions of calcium stearate can be, for example, 15 parts, 16 parts, 17 parts, 18 parts, 19 parts, and 20 parts.

[0052] In a preferred embodiment, the specific surface area of ​​the saponin powder can be 350 m 2 / kg or more.

[0053] In the present invention, the soapberry powder is a fine powder obtained by drying natural soapberry and grinding it into powder, with a specific surface area of ​​350m 2 / kg. Gleditsia powder contains a large amount of natural tea saponin, which contains a large amount of surfactants, which can introduce uniform tiny bubbles into self-compacting concrete with strength grade C100 and above, thereby reducing the performance tension of cement paste, improving dispersibility, increasing paste volume, and reducing the viscosity of concrete mixture, which can effectively improve the flowability of self-compacting concrete with strength grade C100 and above.

[0054] In a preferred embodiment, the density of the glass microspheres can be 2.2 g / cm 3 , its specific surface area can be between 3250 and 3400 m 2 / kg, for example, 3250m 2 / kg、3300m 2 / kg、3350m 2 / kg、3400m 2 / kg, but not limited to.

[0055] In the present invention, glass microspheres are building materials extracted from fly ash, which are ultrafine spherical fly ash extracts, and their main components are active SiO2 and active Al2O3. Because their particles are spherical, they can play a "ball" lubrication role and have a strong morphological effect; coupled with their lower water demand ratio, they can play a water-reducing role, and can effectively reduce viscosity and increase fluidity in cement paste.

[0056] In a preferred embodiment, the specific surface area of ​​the ultrafine limestone powder can be selected to be 400-450 m 2 / kg, with a typical but non-limiting specific surface area of, for example, 400 m 2 / kg, 410m 2 / kg, 420m2 / kg, 430m 2 / kg, 440m 2 / kg, 450m 2 / kg.

[0057] In the present invention, the main component of the ultrafine limestone powder is calcium carbonate, and its specific surface area is 400-450m 2 / kg, ultrafine limestone powder has lower surface energy and small water demand. It can reduce the viscosity of self-compacting concrete with strength grade C100 and above, and at the same time play a filling role and reduce porosity.

[0058] In the present invention, calcium stearate is a white powder with a molecular formula of C 36 H 70 CaO4 mainly plays the role of foam stabilizer. The tiny bubbles produced by soapnut powder play a great role in reducing viscosity. Calcium stearate is adsorbed on the surface of cement particles. Some cement particles become hydrophobic particles and adsorb on the gas-liquid surface of the bubbles, preventing the bubbles from further growing and merging. The bubbles can be stabilized for a longer period of time. The synergistic effect of soapnut powder and calcium stearate plays the role of entraining and stabilizing air.

[0059] In a preferred embodiment, material B comprises the following components in parts by mass:

[0060] 10-20 parts of sodium tripolyphosphate, 10-15 parts of sodium thiosulfate, 20-30 parts of rheological agent, and 44-54 parts of water.

[0061] In the present invention, typical but non-limiting mass fractions of sodium tripolyphosphate can be, for example, 10 parts, 12 parts, 14 parts, 16 parts, 18 parts, and 20 parts; typical but non-limiting mass fractions of sodium thiosulfate can be, for example, 10 parts, 11 parts, 12 parts, 13 parts, 14 parts, and 15 parts; typical but non-limiting mass fractions of rheological agent can be, for example, 20 parts, 22 parts, 24 parts, 26 parts, 28 parts, and 30 parts; typical but non-limiting mass fractions of water can be, for example, 44 parts, 46 parts, 48 ​​parts, 50 parts, 52 parts, and 54 parts.

[0062] In the present invention, sodium tripolyphosphate is an inorganic compound with the chemical formula Na5P3O 10 , density is 2.52g / cm 3 Sodium tripolyphosphate forms a complex with calcium ions of ordinary Portland cement, thereby delaying cement hydration, reducing hydration heat, and prolonging setting time. It can keep the plasticity of fresh high-strength concrete for a long time and reduce the early viscosity of high-strength concrete. Sodium thiosulfate is a white powder with the chemical formula Na2S2O3 and a density of 2.52g / cm 3Sodium thiosulfate can be quickly dissolved in water, increase the sulfate content in cement clinker, react with the hydration product of tricalcium aluminate in cement clinker to form calcium sulfonate, reduce early segregation and bleeding, and can synergize with saponin powder to increase the slurry volume, so as to achieve better wrapping of sandstone aggregate; the rheological agent is a polyether polymer, a light-colored liquid, with a solid content of 20% and a density of 1.02-1.03 g / cm 3 The rheological properties of ultra-high strength self-compacting concrete can be improved, viscosity can be reduced, and segregation and bleeding can be reduced; the water can be ordinary tap water, but is not limited to this.

[0063] In a preferred embodiment, material A comprises the following components in parts by mass:

[0064] 25-30 parts of sapodilla powder, 40-50 parts of glass microspheres, 10-13 parts of ultrafine limestone powder, and 16-19 parts of calcium stearate;

[0065] Material B includes the following components by mass:

[0066] 15-20 parts of sodium tripolyphosphate, 10-13 parts of sodium thiosulfate, 25-30 parts of rheological agent, and 44-50 parts of water.

[0067] The self-compacting concrete viscosity reducer provided by the present invention, through the coordinated coordination of various components and their mass ratios, not only achieves the purpose of effectively reducing the viscosity of self-compacting concrete of strength grade C100 and above, but also realizes the technical effects of good homogeneity, no stratification and segregation, and high strength of the self-compacting concrete, thereby effectively solving the problem that ultra-high-strength concrete is difficult to construct due to its high viscosity, and also improves its homogeneity and mechanical properties.

[0068] According to a second aspect of the present invention, there is provided a method for preparing the self-compacting concrete viscosity reducer as described in any one of the above, comprising the following steps:

[0069] The components are mixed to obtain material A;

[0070] The components are mixed to obtain material B.

[0071] In the present invention, the components in the A material are mixed in proportion to obtain the A material.

[0072] In the present invention, sodium tripolyphosphate and sodium thiosulfate in material B are added to water in sequence, stirred evenly, and then the rheological agent solution is added, and then stirred evenly to obtain material B.

[0073] The method for preparing the self-compacting concrete viscosity reducer provided by the invention has simple process, high efficiency and is suitable for factory production.

[0074] According to a third aspect of the present invention, there is provided a method for using the self-compacting concrete viscosity reducer as described in any one of the above, comprising the following steps:

[0075] When mixing self-compacting concrete, first add material A and mix, then add material B and other admixtures and mix.

[0076] In the mixing process of self-compacting concrete with strength grade C100 or above, the material A is first added and mixed before other admixtures are added, and then the material B is added into the concrete together with other admixtures and mixed.

[0077] The method for using the self-compacting concrete viscosity reducer provided by the present invention can significantly reduce the viscosity of self-compacting concrete of strength grade C100 and above, and can effectively improve the construction performance of self-compacting concrete of strength grade C100 and above, which not only solves the technical problem that concrete is difficult to construct due to its high viscosity, but also enables the concrete to have the advantages of good homogeneity, no stratification and segregation, and high strength.

[0078] In a preferred embodiment, the addition amount of material A of the present invention can be 4-6% of the mass of cement, for example, 4%, 5%, 6%, but not limited to this, which is more conducive to making the self-compacting concrete of strength grade C100 and above have the advantages of good homogeneity, no stratification and segregation, and high strength.

[0079] In a preferred embodiment, the addition amount of material B of the present invention can be 0.8-1.4% of the mass of cement, for example, it can be 0.8%, 0.9%, 1.0%, 1.1%, 1.2%, 1.3%, 1.4%, but not limited to this, which is more conducive to making self-compacting concrete of strength grade C100 and above have the advantages of suitable viscosity, no stratification and segregation, and high strength.

[0080] According to a fourth aspect of the present invention, there is provided a use of the self-compacting concrete viscosity reducer described in any one of the above items in concrete construction.

[0081] The application of the self-compacting concrete viscosity reducer provided by the invention has good concrete construction effect and quality, and has achieved outstanding application effect.

[0082] The present invention is further described below by way of examples. Unless otherwise specified, the materials in the examples are prepared according to existing methods or directly purchased from the market.

[0083] Examples 1-5

[0084] Example 1-5 provides a self-compacting concrete viscosity reducer, including material A and material B, and the components and their mass ratios are shown in Table 1;

[0085] Among them, the specific surface area of ​​​​the A material component, saponin powder, is 350m 2 / kg; the main components of glass microspheres are active SiO2 and active Al2O3, and the density of glass microspheres is 2.2g / cm 3 , with a specific surface area of ​​3250~3400m 2 / kg; The main component of ultrafine limestone powder is calcium carbonate, and the specific surface area of ​​ultrafine limestone powder is 400~450m 2 / kg;

[0086] Material B components: sodium tripolyphosphate, industrial grade, content greater than 99%; sodium thiosulfate, industrial grade, content greater than 99.5%; rheological agent is polyether high molecular polymer, solid content is 20%; water is ordinary tap water.

[0087] Table 1

[0088]

[0089] Example 6

[0090] This embodiment is a method for preparing the self-compacting concrete viscosity reducer of Embodiments 1-5, comprising the following steps:

[0091] Mix the components in material A evenly according to the proportion to obtain material A.

[0092] Add the sodium tripolyphosphate and sodium thiosulfate in material B into water in proportion, stir evenly, then add the rheological agent solution, and then stir evenly to obtain material B.

[0093] Comparative Example 1

[0094] The difference between this comparative example and Example 3 is that the material A of this comparative example does not contain saponin powder;

[0095] The remaining components and their mass ratios in material A are the same as those in Example 3; material B is the same as that in Example 3;

[0096] The preparation method refers to Example 6 to obtain a self-compacting concrete viscosity reducer.

[0097] Compared with Example 3, the viscosity reducer provided in this comparative example lacks saponin powder, so it is impossible to introduce uniformly dispersed microbubbles, and the viscosity reducing effect of the viscosity reducer is greatly adversely affected.

[0098] Comparative Example 2

[0099] The difference between this comparative example and Example 3 is that the soapberry powder is replaced with glass microbeads in an equal amount in the material A of this comparative example;

[0100] The remaining components and their mass ratios in material A are the same as those in Example 3; material B is the same as that in Example 3;

[0101] The preparation method refers to Example 6 to obtain a self-compacting concrete viscosity reducer.

[0102] Compared with Example 3, the viscosity reducer provided in this comparative example cannot introduce evenly distributed bubbles due to the lack of soapnut powder. Although the glass microspheres can play a certain rolling role, they cannot replace the air-entraining function of soapnut powder.

[0103] Comparative Example 3

[0104] The difference between this comparative example and Example 3 is that the material A of this comparative example does not contain glass microspheres;

[0105] The remaining components and their mass ratios in material A are the same as those in Example 3; material B is the same as that in Example 3;

[0106] The preparation method refers to Example 6 to obtain a self-compacting concrete viscosity reducer.

[0107] Compared with Example 3, the viscosity reducer provided in this comparative example has the defects of lacking the lubrication and rolling effect of the glass microspheres, which adversely affects the viscosity reduction effect, and lacking the filling and active effect of the glass microspheres, which also adversely affects the strength.

[0108] Comparative Example 4

[0109] The difference between this comparative example and Example 3 is that the material A of this comparative example does not contain ultrafine limestone powder;

[0110] The remaining components and their mass ratios in material A are the same as those in Example 3; material B is the same as that in Example 3;

[0111] The preparation method refers to Example 6 to obtain a self-compacting concrete viscosity reducer.

[0112] Compared with Example 3, the viscosity reducer provided in this comparative example lacks ultrafine limestone powder, so the water reduction, viscosity reduction and filling effects are weakened, resulting in adverse effects on the construction performance and mechanical properties of the concrete.

[0113] Comparative Example 5

[0114] The difference between this comparative example and Example 3 is that the material A of this comparative example does not contain calcium stearate;

[0115] The remaining components and their mass ratios in material A are the same as those in Example 3; material B is the same as that in Example 3;

[0116] The preparation method refers to Example 6 to obtain a self-compacting concrete viscosity reducer.

[0117] Compared with Example 3, the viscosity reducer provided in this comparative example is unable to stabilize the tiny uniform bubbles generated by the saponin powder due to the lack of calcium stearate, which results in the inability to reduce the viscosity and the inability to maintain the workability of the ultra-high-strength concrete for a period of time.

[0118] Comparative Example 6

[0119] The difference between this comparative example and Example 3 is that in the material A of this comparative example, calcium stearate is replaced by an equal amount of saponin powder;

[0120] The remaining components and their mass ratios in material A are the same as those in Example 3; material B is the same as that in Example 3;

[0121] The preparation method refers to Example 6 to obtain a self-compacting concrete viscosity reducer.

[0122] Compared with Example 3, the viscosity reducer provided in this comparative example can introduce more uniformly distributed tiny bubbles, but cannot stabilize these bubbles, and the bubble content is too high, which will reduce the strength of the concrete.

[0123] Comparative Example 7

[0124] The difference between this comparative example and Example 3 is that the material B of this comparative example does not contain sodium tripolyphosphate;

[0125] Material A is the same as that in Example 3; the remaining components and their mass ratios in Material B are the same as those in Example 3;

[0126] The preparation method refers to Example 6 to obtain a self-compacting concrete viscosity reducer.

[0127] Compared with Example 3, the viscosity reducer provided in this comparative example lacks sodium tripolyphosphate and therefore cannot play a retarding role, resulting in a decrease in the collapse retention capacity of the ultra-high-strength concrete, which is not conducive to the construction of the concrete.

[0128] Comparative Example 8

[0129] The difference between this comparative example and Example 3 is that the material B of this comparative example does not contain sodium thiosulfate;

[0130] Material A is the same as that in Example 3; the remaining components and their mass ratios in Material B are the same as those in Example 3;

[0131] The preparation method refers to Example 6 to obtain a self-compacting concrete viscosity reducer.

[0132] Compared with Example 3, the viscosity reducer provided in this comparative example lacks sodium thiosulfate and therefore cannot make up for the problem of insufficient early strength of ultra-high-strength concrete caused by air entrainment and slow setting.

[0133] Comparative Example 9

[0134] The difference between this comparative example and Example 3 is that sodium thiosulfate is replaced by an equal amount of sodium tripolyphosphate in material B of this comparative example;

[0135] Material A is the same as that in Example 3; the remaining components and their mass ratios in Material B are the same as those in Example 3;

[0136] The preparation method refers to Example 6 to obtain a self-compacting concrete viscosity reducer.

[0137] Compared with Example 3, the defect of the viscosity reducer provided in this comparative example is that the retarding time of the concrete is too long, resulting in insufficient early strength of the concrete.

[0138] Test example

[0139] The viscosity reducers of Examples 1-5 and Comparative Examples 1-9 were respectively added to C100 strength grade self-compacting concrete and mixed, and the performance of the corresponding groups of concrete was tested, which were respectively recorded as test group 1, test group 2, test group 3, test group 4, test group 5, comparison group 1, comparison group 2, comparison group 3, comparison group 4, comparison group 5, comparison group 6, comparison group 7, comparison group 8 and comparison group 9. The test results are shown in Table 2.

[0140] Specific method: During the concrete mixing process, material A is added before other admixtures are added for mixing, and then material B and other admixtures are added to the concrete for mixing to obtain reduced viscosity concrete;

[0141] The amount of material A added is 5% of the cement mass, and the amount of material B added is 1.1% of the cement mass;

[0142] The mix ratio of cement paste is: cement, silica fume, fly ash, water and admixture is 420:100:180:126:5.6;

[0143] The mix ratio of concrete is: cement, silica fume, fly ash, sand, stone, water and admixture is 420:100:180:630:944:126:7.

[0144] The expansion test is based on GB / T50080-2002 "Standard Test Method for Performance of Ordinary Concrete Mixtures", the 3d and 28d compressive strength test of concrete is based on GB / T50081-2002 "Standard Test Method for Mechanical Properties of Ordinary Concrete", and the viscosity of cement paste is measured according to the method in TB / T 3275-2018 "Railway Concrete".

[0145] Table 2

[0146]

[0147] It can be seen from the data in Table 2 that the self-compacting concrete viscosity reducer provided by the present invention, with the coordinated cooperation of each component and its mass ratio, is suitable for self-compacting concrete of strength grade C100 and above, and can not only effectively reduce the viscosity of ultra-high-strength concrete and improve its construction performance, but also can improve the homogeneity of concrete, and improve the mechanical properties of self-compacting concrete of strength grade C100 and above.

[0148] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A self-compacting concrete viscosity reducer, characterized in that: Including A material and B material; The A material comprises the following components: Gleditsia sinensis powder, glass microspheres, ultrafine limestone powder, and calcium stearate; The B material includes the following components: Sodium tripolyphosphate, sodium thiosulfate, a rheological agent, and water; The A material includes the following components by mass: 20-30 parts of sapodilla powder, 40-50 parts of glass microspheres, 10-15 parts of ultrafine limestone powder, and 15-20 parts of calcium stearate; The B material includes the following components by mass: 10-20 parts of sodium tripolyphosphate, 10-15 parts of sodium thiosulfate, 20-30 parts of rheological agent, and 44-54 parts of water.

2. The self-compacting concrete viscosity reducer according to claim 1, characterized in that: The specific surface area of ​​the saponin powder is 350 m 2 / kg or more; The density of the glass microspheres is 2.2 g / cm 3 , with a specific surface area of ​​3250~3400 m 2 / kg; The specific surface area of ​​the ultrafine limestone powder is 400-450 m 2 / kg.

3. The self-compacting concrete viscosity reducer according to claim 1, characterized in that: The A material includes the following components by mass: 25-30 parts of sapodilla powder, 40-50 parts of glass microspheres, 10-13 parts of ultrafine limestone powder, and 16-19 parts of calcium stearate; The B material includes the following components by mass: 15-20 parts of sodium tripolyphosphate, 10-13 parts of sodium thiosulfate, 25-30 parts of rheological agent, and 44-50 parts of water.

4. A method for preparing the self-compacting concrete viscosity reducer according to any one of claims 1 to 3, characterized in that: The following steps are involved: The components are mixed to obtain material A; The components are mixed to obtain material B.

5. A method for using the self-compacting concrete viscosity reducer according to any one of claims 1 to 3, characterized in that: The following steps are involved: When mixing self-compacting concrete, first add material A and mix, then add material B and other admixtures and mix.

6. The method of use according to claim 5, characterized in that: The self-compacting concrete includes self-compacting concrete with strength grade of C100 and above.

7. The method of use according to claim 5, characterized in that: The amount of material A added is 4-6% of the cement mass; The added amount of the B material is 0.8-1.4% of the cement mass.

8. Use of the self-compacting concrete viscosity reducer according to any one of claims 1 to 3 in concrete construction.

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