Concrete admixture for inhibiting negative effects of flocculants, and preparation method and application thereof

Abstract

The application relates to the technical field of concrete admixtures, and particularly discloses a concrete admixture for inhibiting negative effects of flocculants and a preparation method and application thereof. The concrete admixture for inhibiting negative effects of flocculants comprises the following components in mass fractions: 1-2 parts of a water reducing agent, 1-1.5 parts of hydroxyethylidene diphosphonic acid, 0.1-0.5 parts of sodium monofluorophosphate, 0.1-0.5 parts of glucomannan and 0.05-0.1 parts of turpentine. The concrete admixture for inhibiting negative effects of flocculants can effectively neutralize or weaken the adverse effects of flocculants on the performance of concrete, while keeping good workability and mechanical properties of the concrete, so that the long-term durability of the concrete is comprehensively improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of concrete admixtures, in particular to a concrete admixture for inhibiting the negative effects of flocculants and a preparation method and application thereof. BACKGROUND

[0002] Mechanical sand, which is artificially produced by mechanically crushing and screening natural rocks, mine tailings or industrial waste residues, inevitably contains fine particles and dust during the production process. In order to improve the classification efficiency and reduce water consumption during the production of mechanical sand, flocculants such as polyacrylamide, polydimethyl diallyl ammonium chloride and its derivatives are usually added in the wet production process. These flocculants can gather fine particles suspended in water into larger flocs through charge neutralization and bridging action, facilitating sedimentation and separation.

[0003] However, when these mechanical sands with flocculant residues are used as concrete aggregates, they may cause negative effects in concrete. First, the presence of flocculants can enhance the interfacial adhesion between cement paste and aggregates, significantly reducing the fluidity of concrete mixture and increasing the difficulty of construction. Second, the flocculants affect the dispersibility of cement particles, leading to uneven distribution of water in the concrete, aggravating bleeding and affecting the surface quality of the concrete. In addition, the flocculants may interfere with the normal hydration process of cement, resulting in slow development of early strength of concrete, even insufficient late strength, and may cause deterioration of concrete pore structure, increase permeability, reduce impermeability and frost resistance, and seriously affect the long-term durability of concrete.

[0004] Therefore, it is crucial to solve the negative effects caused by flocculants, which not only can improve the quality of concrete and ensure good workability and mechanical properties of concrete, but also can effectively utilize mechanical sand as building aggregate, helping to reduce the dependence on natural river sand, alleviate resource shortages and promote sustainable development of the construction industry. SUMMARY

[0005] To solve the negative effects caused by flocculants, the present application provides a concrete admixture for inhibiting the negative effects of flocculants and a preparation method and application thereof. The concrete admixture for inhibiting the negative effects of flocculants provided by the present application can effectively neutralize or weaken the adverse effects of flocculants on the performance of concrete, while maintaining good workability and mechanical properties of concrete, thereby comprehensively improving the long-term durability of concrete.

[0006] In a first aspect, the present application provides a concrete admixture for inhibiting the negative effects of flocculants, which adopts the following technical solution:

[0007] The application discloses a concrete admixture for inhibiting negative effects of flocculants, which comprises the following components in mass fractions: 1-2 parts of a water reducing agent, 1-1.5 parts of hydroxyethylidene diphosphonic acid, 0.1-0.5 parts of sodium monofluorophosphate, 0.1-0.5 parts of glucomannan and 0.05-0.1 parts of turpentine.

[0008] In the technical solution, the hydroxyethylidene diphosphonic acid, the sodium monofluorophosphate, the glucomannan and the turpentine are synergistically combined, and are cooperated with the water reducing agent, so that the negative effects of the residual flocculants in the machine-made sand on the concrete are obviously inhibited. Specifically, the hydroxyethylidene diphosphonic acid prevents the precipitation of calcium ions and other metal ions by complexing the calcium ions and the other metal ions, and reduces the cement particle agglomeration phenomenon; the sodium monofluorophosphate forms a protective film in the concrete to prevent the erosion of chloride ions; the combination of the two not only reduces the cement particle aggregation caused by the flocculants, but also enhances the durability and corrosion resistance of the concrete; meanwhile, the glucomannan, as a natural polysaccharide, can form a protective film in the concrete to reduce water loss and improve the workability; and the turpentine, as a surfactant, reduces the surface tension of water to promote the uniform dispersion of cement particles and reduce the agglomeration phenomenon, so that the bleeding phenomenon caused by the flocculants is effectively inhibited and good fluidity is maintained. When the four components of the hydroxyethylidene diphosphonic acid, the sodium monofluorophosphate, the glucomannan and the turpentine are cooperated with the water reducing agent, the bleeding rate of the concrete can be effectively reduced, and the fluidity of the concrete can be improved, so that the good workability and mechanical properties of the concrete are ensured.

[0009] Preferably, 2-5 parts of basalt fibers are further included.

[0010] In the technical solution, the basalt fibers are added to further improve the strength and durability of the concrete and further reduce the negative effects of the flocculants on the concrete. The basalt fibers can form a three-dimensional network structure in the concrete to effectively prevent the formation and development of micro-cracks in the concrete and improve the crack resistance of the concrete. Meanwhile, the basalt fibers can also chemically react with other components in the concrete to form chemical bonds, so that the strength and durability of the concrete are further enhanced.

[0011] Preferably, the basalt fibers have a length of 6mm to 12mm and a diameter of 8um to 15um.

[0012] In the technical solution, the basalt fibers having a length of 6mm to 12mm and a diameter of 8um to 15um are selected, so that the network structure formed by the basalt fibers in the concrete is more compact, the mechanical properties and durability of the concrete are further improved, and the negative effects of the flocculants are better inhibited.

[0013] Preferably, the water reducing agent is a polycarboxylate-based high-efficiency water reducing agent.

[0014] In the technical solution, the polycarboxylate superplasticizer is selected as the water reducing agent component of the application, so that the synergistic effect of each component can be better played, the negative effect of the flocculating agent can be further inhibited, and the comprehensive performance of the concrete can be improved. The polycarboxylate superplasticizer has excellent dispersion performance and water reducing effect, can effectively reduce the water-cement ratio of the concrete, and improve the strength and durability of the concrete. Meanwhile, the functional groups such as carboxyl groups in the molecular structure of the polycarboxylate superplasticizer can be complexed with metal ions such as calcium ions in the concrete, further reducing the agglomeration of cement particles, and being beneficial to the uniform dispersion of the concrete and the maintenance of good workability.

[0015] In a second aspect, the application provides a preparation method of the concrete admixture for inhibiting the negative effect of the flocculating agent, which adopts the following technical solution:

[0016] The preparation method of the concrete admixture for inhibiting the negative effect of the flocculating agent comprises the following steps: adding the water reducing agent into 10 times of water, stirring and dissolving, then sequentially adding hydroxyethylidene diphosphonic acid, sodium monofluorophosphate, glucomannan and turpentine oil, mixing uniformly to obtain a mixed solution, drying the mixed solution, and grinding to obtain the concrete admixture for inhibiting the negative effect of the flocculating agent.

[0017] In the technical solution, the water reducing agent is first added into 10 times of water for stirring and dissolving, which ensures that the water reducing agent can be uniformly dispersed in the water, and provides a good dispersion basis for the subsequent addition of other components. Then, the hydroxyethylidene diphosphonic acid, sodium monofluorophosphate, glucomannan and turpentine oil are sequentially added and mixed uniformly, and the mixed solution is dried and ground to obtain the concrete admixture for inhibiting the negative effect of the flocculating agent. The preparation method is simple and easy to implement, is suitable for industrial production, and can meet the demand of large-scale application.

[0018] Preferably, the water reducing agent is added into 10 times of water, stirred and dissolved, then hydroxyethylidene diphosphonic acid, sodium monofluorophosphate, glucomannan and turpentine oil are sequentially added and mixed uniformly, and the stirring is continued to obtain a mixed solution. The mixed solution is dried and ground, and basalt fibers are added and stirred uniformly to obtain the concrete admixture for inhibiting the negative effect of the flocculating agent.

[0019] In the technical solution, the basalt fibers are added during the preparation process, which further improves the use effect of the admixture, and the admixture can more effectively inhibit the negative effect of the flocculating agent.

[0020] In a third aspect, the application provides the application of the concrete admixture for inhibiting the negative effect of the flocculating agent, which adopts the following technical solution:

[0021] The application relates to an application of a concrete admixture for inhibiting the negative effect of a flocculating agent, and the concrete admixture for inhibiting the negative effect of the flocculating agent is added into concrete.

[0022] Preferably, the concrete admixture for inhibiting the negative effect of the flocculating agent is added into the concrete in an amount of 0.1% to 5% of the total mass of the concrete.

[0023] In the technical scheme, the concrete admixture for inhibiting the negative effect of the flocculating agent is added into the concrete in an amount of 0.1% to 5% of the total mass of the concrete, so that the negative influence of the residual flocculating agent in the manufactured sand on the performance of the concrete can be effectively neutralized or weakened, the fluidity of the concrete is remarkably improved, the bleeding rate is reduced, and thus the work performance of the concrete is improved. Meanwhile, the admixture can also enhance the durability and corrosion resistance of the concrete, improve the strength and crack resistance of the concrete, and ensure that the concrete has good mechanical properties.

[0024] In conclusion, the application has at least one of the following beneficial technical effects:

[0025] 1. The concrete admixture for inhibiting the negative effect of the flocculating agent provided by the application not only remarkably improves the fluidity and work performance of the concrete, reduces the bleeding rate, but also remarkably enhances the durability and corrosion resistance of the concrete, and improves the strength and crack resistance of the concrete.

[0026] 2. The preparation method is simple and easy to operate, is suitable for industrial production, and can meet the demand of large-scale application. DETAILED DESCRIPTION

[0027] In order to better illustrate the purpose, technical scheme and advantages of the application, the application will be further described in combination with specific examples.

[0028] Example 1

[0029] The concrete admixture for inhibiting the negative effect of the flocculating agent comprises 1 kg of a water reducing agent, 1 kg of hydroxyethylidene diphosphonic acid, 0.1 kg of sodium monofluorophosphate, 0.1 kg of glucomannan and 0.05 kg of turpentine.

[0030] The hydroxyethylidene diphosphonic acid is purchased from Shandong Longhui Chemical Co., Ltd.

[0031] The sodium monofluorophosphate is purchased from Shandong Jinshengtai Chemical Co., Ltd.

[0032] The glucomannan is purchased from Shaanxi Shengqi Biological Technology Co., Ltd.

[0033] The turpentine is purchased from Jinan Yingshun Chemical Co., Ltd.

[0034] The water reducing agent is a polycarboxylic acid high-efficiency water reducing agent, which is purchased from Shanghai Hengchuang Chemical Co., Ltd. and has a model number of PC-1055.

[0035] The preparation method of the concrete admixture for inhibiting the negative effect of the flocculating agent comprises the following steps: the water reducing agent is added into 10 times of water, and after stirring and dissolving, hydroxyethylidene diphosphonic acid, sodium monofluorophosphate, glucomannan and turpentine are sequentially added and uniformly mixed to obtain a mixed solution, the mixed solution is subjected to drying treatment, and grinding is performed to obtain the concrete admixture for inhibiting the negative effect of the flocculating agent.

[0036] Example 2

[0037] The concrete admixture for inhibiting the negative effect of the flocculating agent is different from that in Example 1, and comprises 2 kg of the water reducing agent, 1.5 kg of the hydroxyethylidene diphosphonic acid, 0.5 kg of the sodium monofluorophosphate, 0.5 kg of the glucomannan and 0.1 kg of the turpentine.

[0038] The preparation method of the concrete admixture for inhibiting the negative effect of the flocculating agent comprises the following steps: the water reducing agent is added into 10 times of water, and after stirring and dissolving, hydroxyethylidene diphosphonic acid, sodium monofluorophosphate, glucomannan and turpentine are sequentially added and uniformly mixed to obtain a mixed solution, the mixed solution is subjected to drying treatment, and grinding is performed to obtain the concrete admixture for inhibiting the negative effect of the flocculating agent.

[0039] Example 3

[0040] The concrete admixture for inhibiting the negative effect of the flocculating agent is different from that in Example 1, and comprises 1.5 kg of the water reducing agent, 1.2 kg of the hydroxyethylidene diphosphonic acid, 0.3 kg of the sodium monofluorophosphate, 0.3 kg of the glucomannan and 0.08 kg of the turpentine.

[0041] The preparation method of the concrete admixture for inhibiting the negative effect of the flocculating agent comprises the following steps: the water reducing agent is added into 10 times of water, and after stirring and dissolving, hydroxyethylidene diphosphonic acid, sodium monofluorophosphate, glucomannan and turpentine are sequentially added and uniformly mixed to obtain a mixed solution, the mixed solution is subjected to drying treatment, and grinding is performed to obtain the concrete admixture for inhibiting the negative effect of the flocculating agent.

[0042] Example 4

[0043] The concrete admixture for inhibiting the negative effect of the flocculating agent is different from that in Example 1, and further comprises 2 kg of basalt fibers.

[0044] The basalt fibers have a length of 6 mm to 12 mm and a diameter of 8 μm to 15 μm.

[0045] The preparation method of the concrete admixture for inhibiting the negative effect of flocculants comprises the following steps: adding a water reducing agent into 10 times amount of water, stirring and dissolving, then adding hydroxyethylidene diphosphonic acid, sodium monofluorophosphate, glucomannan and turpentine oil in sequence, mixing uniformly, continuously stirring uniformly to obtain a mixed solution, drying the mixed solution, grinding, then adding basalt fibers, stirring uniformly to obtain the concrete admixture for inhibiting the negative effect of flocculants.

[0046] Example 5

[0047] The concrete admixture for inhibiting the negative effect of flocculants is different from that in Example 1 in that it further comprises 5 kg of basalt fibers.

[0048] The basalt fibers have a length of 6 mm to 12 mm and a diameter of 8 μm to 15 μm.

[0049] The preparation method of the concrete admixture for inhibiting the negative effect of flocculants comprises the following steps: adding a water reducing agent into 10 times amount of water, stirring and dissolving, then adding hydroxyethylidene diphosphonic acid, sodium monofluorophosphate, glucomannan and turpentine oil in sequence, mixing uniformly, continuously stirring uniformly to obtain a mixed solution, drying the mixed solution, grinding, then adding basalt fibers, stirring uniformly to obtain the concrete admixture for inhibiting the negative effect of flocculants.

[0050] Comparative Example 1

[0051] The concrete admixture for inhibiting the negative effect of flocculants is different from that in Example 1 in that it does not contain hydroxyethylidene diphosphonic acid.

[0052] Comparative Example 2

[0053] The concrete admixture for inhibiting the negative effect of flocculants is different from that in Example 1 in that it does not contain sodium monofluorophosphate.

[0054] Comparative Example 3

[0055] The concrete admixture for inhibiting the negative effect of flocculants is different from that in Example 1 in that it does not contain glucomannan.

[0056] Comparative Example 4

[0057] The concrete admixture for inhibiting the negative effect of flocculants is different from that in Example 1 in that it does not contain turpentine oil.

[0058] Performance detection

[0059] The detection sample is the concrete admixture for inhibiting the negative effect of flocculants in each of the above examples and comparative examples.

[0060] Preparation of C30 concrete: 210 kg of cement, 60 kg of slag, 80 kg of fly ash, 790 kg of machine-made sand, 1030 kg of gravel, 170 kg of water, and the test sample dosage is 4%, and the flocculating agent content in the machine-made sand is 0.03%.

[0061] Test method: According to GB / T 50080-2016 "Standard Test Methods for Properties of Fresh Ordinary Concrete", the slump and spread of the concrete mixture are detected, and according to GB / T 50081-2019 "Standard Test Methods for Physical and Mechanical Properties of Concrete", the compressive strength of the concrete is detected.

[0062] The above detection is performed on three sets of parallel tests for each sample, and the average value is taken as the result, as shown in Table 1.

[0063] Table 1:

[0064]

[0065] In combination with the analysis of the concrete admixture for inhibiting the negative effects of the flocculating agent in the above embodiments and comparative examples, it can be seen that the concrete admixture for inhibiting the negative effects of the flocculating agent provided in the present application, on the basis of containing hydroxy ethylene diphosphonic acid, sodium monofluorophosphate, glucomannan and turpentine, can significantly improve the workability and mechanical properties of the concrete through the synergistic effect of the components.

[0066] In combination with the analysis of Example 1 and Comparative Examples 1-4, it can be seen that Comparative Examples 1-4 lack any one of hydroxy ethylene diphosphonic acid, sodium monofluorophosphate, glucomannan and turpentine compared with Example 1, and the slump, spread and compressive strength of the concrete of Example 1 perform well, which further verifies the necessity of simultaneously adding hydroxy ethylene diphosphonic acid, sodium monofluorophosphate, glucomannan and turpentine in the concrete admixture for inhibiting the negative effects of the flocculating agent.

[0067] The specific embodiments are merely an explanation of the present application, and are not a limitation of the present application, and those skilled in the art can make modifications to the embodiments without creative contribution after reading the present specification, but as long as the modifications are within the scope of the claims of the present application, they are protected by the patent law.

Claims

1. A concrete admixture that inhibits the negative effects of flocculants, characterized by, The components include the following quality parts: 1~2 parts of water reducing agent, 1~1.5 parts of hydroxy ethylene diphosphonic acid, 0.1~0.5 parts of sodium monofluorophosphate, 0.1~0.5 parts of glucomannan, 0.05~0.1 parts of turpentine oil.

2. A concrete admixture according to claim 1, characterized in that, It also includes 2~5 parts of basalt fiber.

3. A concrete admixture according to claim 2, wherein The basalt fiber has a length of 6mm to 12mm and a diameter of 8μm to 15μm.

4. The concrete admixture of claim 1, wherein the concrete admixture is characterized by, The water reducing agent is a polycarboxylic acid high efficiency water reducing agent.

5. A method of preparing a concrete admixture for inhibiting the negative effect of flocculants as claimed in claim 1 or 4, characterized in that, The method comprises the following steps: adding water reducing agent into 10 times amount of water, stirring and dissolving, then adding hydroxy ethylene diphosphonic acid, sodium monofluorophosphate, glucomannan and turpentine oil in sequence, mixing uniformly, obtaining a mixed solution, drying the mixed solution, grinding, and obtaining the concrete admixture for inhibiting the negative effect of flocculating agent.

6. A method of preparing a concrete admixture that suppresses the negative effects of flocculants according to claim 2 or 3, characterized in that, The method comprises the following steps: adding water reducing agent into 10 times amount of water, stirring and dissolving, then adding hydroxy ethylene diphosphonic acid, sodium monofluorophosphate, glucomannan and turpentine oil in sequence, mixing uniformly, continuing to stir uniformly, obtaining a mixed solution, drying the mixed solution, grinding, adding basalt fiber, stirring uniformly, and obtaining the concrete admixture for inhibiting the negative effect of flocculating agent.

7. Use of a concrete admixture according to any one of claims 1 to 4 for inhibiting the negative effects of flocculants, characterized in that The concrete admixture for inhibiting the negative effect of flocculating agent is added into concrete.

8. Use of a concrete admixture according to claim 7, characterized in that, The adding amount of the concrete admixture for inhibiting the negative effect of flocculating agent in concrete is 0.1%~5% of the total mass of concrete.

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