A concrete additive and concrete

Abstract

The present invention discloses a concrete additive and concrete. The concrete additive comprises the following components: silica fume, inorganic nanoparticles, hyperbranched polyamide modified by a silane coupling agent, and sodium alginate. The concrete additive prepared by the present invention effectively improves the impermeability and corrosion resistance of concrete through the reasonable combination of hyperbranched polyamide modified by a silane coupling agent with silica fume, inorganic nanoparticles, and sodium alginate, with a specific synergistic effect.

Description

Technical Field

[0001] The present invention belongs to the field of building concrete, and particularly relates to a concrete additive and concrete. Background Art

[0002] In recent years, with the continuous advancement of urban construction, the problems brought about by urban construction have become increasingly apparent. Among them, engineering quality problems caused by the performance of concrete also occur from time to time. Concrete generally refers to a building material obtained by mixing cement as a gelling material, sand and stone as aggregates, and water in a certain proportion.

[0003] In the practical application of concrete in engineering, the crack resistance and impermeability of concrete are the main factors restricting the durability of underground engineering. At the same time, concrete is often exposed to various relatively harsh environments, such as the intrusion of corrosive media around the environment, the change of environmental temperature and humidity, etc. These external conditions will seriously affect the service life of concrete. Therefore, it is necessary to add a protective agent to the concrete for protection. Existing concrete additives have a single function. Using various different additives can achieve different effects. However, when used in combination, if the interaction, selection, proportioning or addition method of various additives is incorrect, it will seriously affect the engineering quality of concrete. Therefore, there is an urgent need for a concrete additive that can improve the impermeability and corrosion resistance of concrete at the same time. Summary of the Invention

[0004] The present invention aims to solve at least one of the technical problems existing in the above prior art. For this purpose, the present invention provides a concrete additive that can improve the impermeability and corrosion resistance of concrete.

[0005] The present invention also provides a preparation method of the above concrete additive.

[0006] The present invention also provides an application of the above concrete additive.

[0007] The present invention also provides a concrete containing the above concrete additive.

[0008] The present invention also provides an application of the above concrete.

[0009] According to one aspect of the present invention, there is provided a concrete additive, which comprises the following components: silica fume, inorganic nanoparticles, hyperbranched polyamide modified by a silane coupling agent, and sodium alginate.

[0010] In some embodiments of the present invention, the concrete additive comprises the following components in parts by mass: 30-50 parts of silica fume, 5-20 parts of inorganic nanoparticles, 15-25 parts of hyperbranched polyamide modified by a silane coupling agent, and 8-15 parts of sodium alginate.

[0011] In some embodiments of the present invention, the concrete additive comprises components in the following parts by mass: 35 - 45 parts of silica fume, 10 - 15 parts of inorganic nanoparticles, 15 - 22 parts of hyperbranched polyamide modified with a silane coupling agent, and 8 - 12 parts of sodium alginate.

[0012] In some embodiments of the present invention, the inorganic nanoparticles include but are not limited to one of nano - silicon dioxide, nano - zirconium oxide, and nano - titanium dioxide.

[0013] In some embodiments of the present invention, the inorganic nanoparticles are nano - silicon dioxide.

[0014] In some embodiments of the present invention, the particle size of the inorganic nanoparticles is 5 - 30 nm.

[0015] In some embodiments of the present invention, the preparation method of the hyperbranched polyamide modified with a silane coupling agent comprises the following steps:

[0016] (1) Dispersing the hyperbranched polyamide in a solvent to obtain a hyperbranched polyamide suspension;

[0017] (2) Adding the silane coupling agent to the hyperbranched polyamide suspension and performing ultrasonic dispersion to obtain a dispersed product;

[0018] (3) Filtering and drying the dispersed product to obtain the product.

[0019] In some embodiments of the present invention, the silane coupling agent includes but is not limited to methyltrimethoxysilane.

[0020] In some embodiments of the present invention, the mass ratio of the added silane coupling agent to the hyperbranched polyamide is 1:(5 - 15).

[0021] In some embodiments of the present invention, the mass ratio of the added silane coupling agent to the hyperbranched polyamide is 1:(8 - 12).

[0022] According to the second aspect of the present invention, a preparation method of the above - mentioned concrete additive is provided. The method comprises the following step: mixing the above - mentioned components to obtain the product.

[0023] According to the third aspect of the present invention, an application of the above - mentioned concrete additive is provided. The application is the application in the preparation of crack - resistant and seepage - proof concrete.

[0024] In some embodiments of the present invention, the application is the application in the preparation of corrosion - resistant concrete.

[0025] In some embodiments of the present invention, the application is the application in the preparation of high - compressive - strength concrete.

[0026] In some embodiments of the present invention, the application is the application in the preparation of high flexural strength concrete.

[0027] According to the fourth aspect of the present invention, a concrete is provided, which contains the above concrete additive, and the concrete has at least one property of high compressive strength, high flexural strength, crack resistance, impermeability and corrosion resistance.

[0028] According to some embodiments of the present invention, it has at least the following beneficial effects: The concrete additive prepared by the solution of the present invention contains silica fume, inorganic nanoparticles, hyperbranched polyamide modified by silane coupling agent and sodium alginate; wherein, the hyperbranched polyamide modified by silane coupling agent can improve its compatibility and adhesion with the concrete matrix, effectively enhance the mechanical properties of the concrete, improve the compressive strength, and improve the impermeability; it can also fill the micropores and cracks in the concrete and reduce the permeability of the concrete; silica fume can improve the compactness and durability of the concrete; the addition of inorganic nanoparticles can further enhance the mechanical properties and compactness of the concrete and improve its impermeability; sodium alginate can be used synergistically with the hyperbranched polyamide modified by silane coupling agent to improve the durability and corrosion resistance of the concrete. The solution of the present invention effectively improves the impermeability and corrosion resistance of the concrete through the reasonable combination of the hyperbranched polyamide modified by silane coupling agent with silica fume, inorganic nanoparticles and sodium alginate and their specific synergistic effect. Specific embodiments

[0029] The concept and technical effects of the present invention will be clearly and completely described below in conjunction with the embodiments to fully understand the purpose, features and effects of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative efforts shall fall within the scope of protection of the present invention.

[0030] In the examples and comparative examples:

[0031] The silica fume was purchased from Shandong Yinfeng New Nano Materials Co., Ltd., and the particle size was 50 - 100 nm.

[0032] Preparation of hyperbranched polyamide: Under a nitrogen atmosphere, methanol and diethylenetriamine, which is 0.2 times the mass of methanol, were added to a three-necked flask at room temperature. After mixing evenly, methyl acrylate, which is 0.15 times the mass of methanol, was added dropwise at a rate of 3 mL / min. After reacting for 5 h, the temperature was raised to 50 °C and the vacuum was pumped. After reacting for 20 min, the temperature was raised to 115 °C again and reacted for 4 h. Then the temperature was raised to 140 °C again and reacted for 3 h to obtain a crude product. The crude product was dispersed in methanol, which is 5 times the mass of the crude product, stirred until dissolved, precipitated and washed with ether, and finally dried in a vacuum drying oven at 60 °C to constant weight to prepare hyperbranched polyamide.

[0033] Example 1

[0034] In this example, an impermeable and corrosion-resistant concrete additive was prepared, which was composed of the following raw materials in parts by mass: 40 parts of silica fume, 10 parts of inorganic nanoparticles (SiO2 nanoparticles were used in this example with a particle size of 5 - 30 nm), 20 parts of hyperbranched polyamide modified with a silane coupling agent, and 10 parts of sodium alginate.

[0035] The preparation method of the hyperbranched polyamide modified with a silane coupling agent includes the following steps:

[0036] (1) Slowly disperse the hyperbranched polyamide in deionized water, which is 20 times its weight, and stir evenly to form a hyperbranched polyamide suspension;

[0037] (2) Add the silane coupling agent (methyltrimethoxysilane) to the hyperbranched polyamide suspension (the mass ratio of the silane coupling agent to the hyperbranched polyamide is 1:10), and set the solution temperature at 40 °C;

[0038] (3) Ultrasonically disperse the above mixed solution sufficiently for 8 min;

[0039] (4) Filter and dry the dispersed product to obtain the hyperbranched polyamide modified with a silane coupling agent.

[0040] Preparation method of the impermeable and corrosion-resistant concrete additive: Mix the above silica fume, inorganic nanoparticles, hyperbranched polyamide modified with a silane coupling agent, and sodium alginate evenly according to the ratio to obtain it.

[0041] Example 2

[0042] In this example, an impermeable and corrosion-resistant concrete additive was prepared, which was composed of the following raw materials in parts by mass: 35 parts of silica fume, 12 parts of inorganic nanoparticles (SiO2 nanoparticles were used in this example with a particle size of 5 - 30 nm), 22 parts of hyperbranched polyamide modified with a silane coupling agent, and 8 parts of sodium alginate.

[0043] The specific preparation method is the same as that of Example 1.

[0044] Example 3

[0045] In this example, an anti-seepage and corrosion-resistant concrete additive was prepared, which was composed of the following raw materials in parts by mass: 45 parts of silica fume, 15 parts of inorganic nanoparticles (SiO2 nanoparticles were used in this example with a particle size of 5 - 30 nm), 15 parts of hyperbranched polyamide modified with silane coupling agent, and 10 parts of sodium alginate.

[0046] The specific preparation method was the same as that in Example 1.

[0047] Example 4

[0048] In this example, an anti-seepage and corrosion-resistant concrete additive was prepared, which was composed of the following raw materials in parts by mass: 40 parts of silica fume, 12 parts of inorganic nanoparticles (SiO2 nanoparticles were used in this example with a particle size of 5 - 30 nm), 16 parts of hyperbranched polyamide modified with silane coupling agent, and 12 parts of sodium alginate.

[0049] The specific preparation method was the same as that in Example 1.

[0050] Comparative Example 1

[0051] In this comparative example, an anti-seepage and corrosion-resistant concrete additive was prepared, which was only different from that in Example 1 in that it did not contain inorganic nanoparticles.

[0052] The specific preparation method was the same as that in Example 1.

[0053] Comparative Example 2

[0054] In this comparative example, an anti-seepage and corrosion-resistant concrete additive was prepared, which was only different from that in Example 1 in that it did not contain modified hyperbranched polyamide.

[0055] The specific preparation method was the same as that in Example 1.

[0056] Comparative Example 3

[0057] In this comparative example, an anti-seepage and corrosion-resistant concrete additive was prepared, which was only different from that in Example 1 in that the hyperbranched polyamide modified with silane coupling agent was replaced with an equal amount of unmodified hyperbranched polyamide in structure.

[0058] The specific preparation method was the same as that in Example 1.

[0059] Test Example

[0060] In this test example, the properties of the anti-seepage and corrosion-resistant concrete additives prepared in Examples 1 - 4 and Comparative Examples 1 - 3 were tested.

[0061] Detection of anti-seepage and corrosion-resistant performance

[0062] The anti-seepage and corrosion-resistant concrete additives in Examples 1-4 and Comparative Examples 1-3 of the present invention were added to concrete, and the addition amount in the concrete was 5% of the cement content in the concrete, and anti-seepage and corrosion-resistant concrete was prepared.

[0063] According to GB / T 50081-2019 "Standard Test Method for Mechanical Properties of Ordinary Concrete"; GB / T 50082-2009 "Standard Test Method for Long-Term Performance and Durability of Ordinary Concrete", relevant performance tests were carried out on the anti-seepage and corrosion-resistant concrete prepared in each example and comparative example. In addition, the concrete prepared without adding additives was used as a blank control group, and the measurement results are shown in Table 1. The experiment was repeated 3 times and the average value was taken.

[0064] Table 1

[0065]

[0066] The results are shown in Table 1. It can be seen from Table 1 that the concrete containing the anti-seepage and corrosion-resistant concrete additive of the present invention has stronger compressive ability, higher flexural strength, stronger anti-seepage water pressure ability, higher corrosion resistance coefficient and lower expansion coefficient compared with the blank control group of ordinary concrete without adding anti-seepage and corrosion-resistant concrete additives; the results show that the components of the present invention can play a good synergistic effect and improve the anti-seepage and corrosion-resistant performance of concrete.

[0067] The above has made a detailed description of the embodiments of the present invention. However, the present invention is not limited to the above embodiments, and various changes can be made without departing from the purpose of the present invention within the knowledge scope of those of ordinary skill in the art. In addition, without conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other.

Claims

1. A concrete additive, characterized in that, The concrete additive comprises the following components in parts by mass: 30-50 parts of silica fume, 5-20 parts of inorganic nanoparticles, 15-25 parts of hyperbranched polyamide modified with a silane coupling agent, and 8-15 parts of sodium alginate.

2. The concrete additive according to claim 1, characterized in that, The inorganic nanoparticles include one of nano-silica, nano-zirconia, and nano-titanium dioxide.

3. The concrete additive according to claim 1, wherein, The particle size of the inorganic nanoparticles is 5-30 nm.

4. The concrete additive according to claim 1, characterized in that, The preparation method of the hyperbranched polyamide modified with a silane coupling agent comprises the following steps: (1) Dispersing the hyperbranched polyamide in a solvent to obtain a hyperbranched polyamide suspension; (2) Adding the silane coupling agent to the hyperbranched polyamide suspension and performing ultrasonic dispersion to obtain a dispersed product; (3) Filtering and drying the dispersed product to obtain the product.

5. The concrete additive according to claim 4, characterized in that, The silane coupling agent includes methyltrimethoxysilane.

6. The concrete additive according to claim 4, characterized in that, The mass ratio of the silane coupling agent to the hyperbranched polyamide added is 1:(5-15).

7. A method for preparing a concrete additive according to any one of claims 1-6, characterized in that, The method comprises the following step: mixing the components to obtain the product.

8. Use of the concrete additive according to any one of claims 1-6 in any one of the following: (1) Preparing crack-resistant and impermeable concrete; (2) Preparing corrosion-resistant concrete; (3) Preparing high-compressive-strength concrete; (4) Preparing high-flexural-strength concrete.

9. A kind of concrete, characterized in that, Containing the concrete additive according to any one of claims 1-6.

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