Concrete anti-cracking and anti-seepage agent and preparation method thereof

Abstract

The present application relates to the technical field of anti-permeation agent, in particular to a concrete anti-cracking anti-permeation agent and a preparation method thereof, which comprises the following steps: mixing sodium gluconate, ethylenediaminetetraacetic acid tetrasodium salt, L-aspartic acid, sodium sulfate, sodium silicate and coated rock wool fiber to prepare an inner anti-permeation material; mixing organosilane, emulsifier and deionized water to prepare an organic silicon emulsion, and adding nano-silicon dioxide into the organic silicon emulsion to prepare an outer anti-permeation material. The concrete anti-cracking anti-permeation agent is composed of the inner anti-permeation material and the outer anti-permeation material. The inner anti-permeation material is directly added into the concrete base material, and insoluble crystals are generated in the cracks and pores during hydration, so that the compactness of the concrete is improved, and the compression resistance and the impermeability are improved. Meanwhile, the outer anti-permeation material forms a continuous hydrophobic film layer on the surface of the concrete, and the pores on the surface layer are filled, so that the compression resistance and the impermeability of the concrete are further improved.

Description

Technical Field

[0001] This invention relates to the field of anti-seepage agent technology, specifically to a concrete crack-resistant and anti-seepage agent and its preparation method. Background Technology

[0002] Building leaks have long been a serious problem that severely disrupts people's lives and work. The main cause of leaks in concrete structures is cracks within the concrete. Concrete components with cracks, under prolonged water seepage, not only affect the normal use of the building but can also severely compromise structural safety and durability, reducing the building's lifespan. Cement-based penetrating crystalline waterproofing materials are typically added directly to the concrete matrix. Upon contact with water, they crystallize, effectively sealing micro-cracks in the concrete and are one of the important methods for solving concrete structure leaks.

[0003] However, due to the heat of hydration, excess water evaporation in concrete creates voids. When these voids become unbalanced with external pressure, they stretch and crack, especially on the surface, where numerous cracks and pores typically form. This provides pathways for corrosive media from the external environment to penetrate the concrete, further accelerating its deterioration. Based on this, a concrete crack-resistant and seepage-proof agent and its preparation method are proposed. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a concrete crack-resistant and seepage-proof agent and its preparation method, which improves the compressive strength and seepage resistance of concrete through the combined action of internal and external seepage-proof materials.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a concrete crack-resistant and seepage-proof agent, comprising an internal seepage-proof material and an external seepage-proof material. By mass percentage, the internal seepage-proof material comprises the following raw materials: 5-10% sodium gluconate, 15-25% L-aspartic acid, 30-35% sodium sulfate, 15-20% sodium silicate, 10-15% coated rock wool fiber, with the balance being tetrasodium ethylenediaminetetraacetate; the external seepage-proof material comprises the following raw materials: 30-40% organosilane, 5-8% emulsifier, 10-20% nano-silica, with the balance being deionized water.

[0006] Preferably, the preparation method of the coated rock wool fiber is as follows: rock wool fiber is added to calcium hydroxide solution and ultrasonically dispersed; then carbon dioxide is introduced until the solution pH is neutral; and then the coated rock wool fiber is obtained by separation and drying.

[0007] Preferably, the concentration of the calcium hydroxide solution is 1-1.5 g / L.

[0008] Preferably, the organosilane is selected from n-octyltriethoxysilane and methyltriethoxysilane; the emulsifier is selected from Span-80 and Tween-80.

[0009] Preferably, the nano-silica is composed of large-particle-size nano-silica and small-particle-size nano-silica in a mass ratio of 1:1; wherein the particle size of the large-particle-size nano-silica is 300-400nm and the particle size of the small-particle-size nano-silica is 50-100nm.

[0010] This invention provides a method for preparing a concrete crack-resistant and seepage-proof agent, comprising the following steps:

[0011] (1) Sodium gluconate, tetrasodium ethylenediaminetetraacetate, L-aspartic acid, sodium sulfate, sodium silicate and coated rock wool fiber are stirred and mixed to prepare an internal seepage-proof material;

[0012] (2) The organosilane, emulsifier and deionized water are stirred and emulsified. Nano-silica is added to the resulting organosilicone emulsion and stirred evenly to obtain an external waterproofing material.

[0013] Preferably, in step (2), the temperature of stirring and emulsifying is 60-70℃, the stirring and emulsifying rate is 800-1200r / min, and the stirring and emulsifying time is 40-60min.

[0014] This invention also provides an application of a concrete crack-resistant and seepage-proof agent, comprising the following steps:

[0015] S1. Mix the internal waterproofing material and concrete base material, pour the mixture, and cure it to obtain concrete blocks.

[0016] S2. Apply an external waterproofing material evenly to the surface of the concrete block, and after natural drying, obtain crack-resistant and waterproof concrete blocks.

[0017] Preferably, in step S1, the curing temperature is 18-22℃ and the curing time is 28 days.

[0018] Preferably, in steps S1 and S2, the dosage of the internal waterproofing material accounts for 0.8-1.2% of the total mass of the concrete matrix; the coating amount of the external waterproofing material is 0.5-0.8 kg / m³. 2 .

[0019] This invention provides a concrete crack-resistant and seepage-proof agent and its preparation method, which has the following advantages compared with the prior art:

[0020] The concrete crack-resistant and seepage-proof agent of this invention is composed of an internal seepage-proof material and an external seepage-proof material. The internal seepage-proof material is directly added to the concrete matrix. During hydration, it generates water-insoluble crystals in cracks and pores, improving the density of the concrete and enhancing its compressive strength and impermeability. At the same time, the external seepage-proof material forms a continuous hydrophobic film layer on the concrete surface and fills the pores formed on the surface, further improving the compressive strength and impermeability of the concrete.

[0021] In this invention, the internal seepage-proof material, in addition to using sodium gluconate and tetrasodium ethylenediaminetetraacetate, also incorporates coated rock wool fibers. By depositing nano-calcium carbonate on the surface of the rock wool fibers, a network structure centered on nano-calcium carbonate is formed during concrete hydration. Furthermore, the rock wool fibers enhance the connection strength of the network structure, which has a positive effect on improving concrete quality.

[0022] The external waterproofing material of this invention contains nano-silica with two particle sizes. On the one hand, with the help of organosilicon emulsion, the nano-silica fills the pores or gaps in the concrete surface and continues to hydrate to produce CSH gel to improve the surface density of the concrete. On the other hand, the use of nano-silica with two particle sizes can form a micro-rough structure on the surface of the organosilicon film, thereby improving the hydrophobic properties. Attached Figure Description

[0023] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:

[0024] Figure 1 These are appearance diagrams of the crack-resistant and seepage-proof concrete blocks in Embodiment 5 and Comparative Example 1 of the present invention;

[0025] Figure 2 These are microscopic images of the coated rock wool fibers in Examples 1 and 2 of the present invention. Detailed Implementation

[0026] The following embodiments are provided to illustrate the implementation of this application in detail, so that the process of how this application uses technical means to solve technical problems and achieve technical effects can be fully understood and implemented accordingly.

[0027] The specific composition of the concrete base material used in the following embodiments is shown in Table 1:

[0028] Table 1 Concrete Base Material

[0029]

[0030] Example 1

[0031] The preparation method of coated rock wool fiber is as follows: rock wool fiber is added to a 1 g / L calcium hydroxide solution and ultrasonically dispersed; then carbon dioxide is bubbled through until the solution pH is neutral; after separation and drying, coated rock wool fiber is obtained, and its microstructure is shown in the figure. Figure 2 As shown on the left, this is rock wool fiber coated with nano-calcium carbonate.

[0032] Example 2

[0033] The preparation method of coated rock wool fiber is as follows: rock wool fiber is added to a 1.5 g / L calcium hydroxide solution and ultrasonically dispersed; then carbon dioxide is bubbled through until the solution pH is neutral; after separation and drying, coated rock wool fiber is obtained, and its microstructure is shown in the figure. Figure 2 As shown on the right, this is rock wool fiber coated with nano-calcium carbonate.

[0034] Example 3

[0035] A concrete crack-resistant and seepage-proof agent, comprising an internal seepage-proof material and an external seepage-proof material, by weight percentage,

[0036] The internal seepage prevention material includes the following raw materials: 10% sodium gluconate, 15% L-aspartic acid, 35% sodium sulfate, 15% sodium silicate, 15% coated rock wool fiber, and the balance is tetrasodium ethylenediaminetetraacetate;

[0037] The external waterproofing material comprises the following raw materials: 40% organosilane (methyltriethoxysilane), 5% emulsifier (Span-80), 20% nano-silica, and the balance being deionized water. The nano-silica is composed of large-particle-size nano-silica (300-400nm) and small-particle-size nano-silica (50-100nm) in a 1:1 mass ratio.

[0038] The preparation method of the above-mentioned concrete crack-resistant and seepage-proof agent includes the following steps:

[0039] (1) Sodium gluconate, tetrasodium ethylenediaminetetraacetate, L-aspartic acid, sodium sulfate, sodium silicate and coated rock wool fiber are stirred and mixed to prepare an internal seepage-proof material;

[0040] (2) The organosilane, emulsifier and deionized water are stirred and emulsified at 60°C at a rate of 1200 r / min for 40 min. Nano silica is added to the obtained organosilicone emulsion and stirred evenly to obtain an external waterproofing material.

[0041] The application of the above-mentioned concrete crack-resistant and seepage-proof agent includes the following steps:

[0042] S1. The internal waterproofing material and concrete base material are mixed and poured, and cured at 22℃ for 28 days to obtain concrete blocks; the content of the internal waterproofing material accounts for 0.8% of the total mass of the concrete base material.

[0043] S2. Apply an external waterproofing material evenly to the surface of the concrete blocks, with a coating amount of 0.8 kg / m². 2 After natural drying, crack-resistant and impermeable concrete blocks are produced.

[0044] In this embodiment, the coated rock wool fiber from Example 1 is used.

[0045] Example 4

[0046] A concrete crack-resistant and seepage-proof agent, comprising an internal seepage-proof material and an external seepage-proof material, by weight percentage,

[0047] The internal seepage prevention material includes the following raw materials: 5% sodium gluconate, 25% L-aspartic acid, 30% sodium sulfate, 20% sodium silicate, 10% coated rock wool fiber, and the balance is tetrasodium ethylenediaminetetraacetate;

[0048] The external waterproofing material comprises the following raw materials: 30% organosilane (n-octyltriethoxysilane), 8% emulsifier (Tween-80), 10% nano-silica, and the balance being deionized water. The nano-silica is composed of large-particle-size nano-silica (300-400nm) and small-particle-size nano-silica (50-100nm) in a 1:1 mass ratio.

[0049] The preparation method of the above-mentioned concrete crack-resistant and seepage-proof agent includes the following steps:

[0050] (1) Sodium gluconate, tetrasodium ethylenediaminetetraacetate, L-aspartic acid, sodium sulfate, sodium silicate and coated rock wool fiber are stirred and mixed to prepare an internal seepage-proof material;

[0051] (2) The organosilane, emulsifier and deionized water are stirred and emulsified at 70°C and at a rate of 800 r / min for 60 min. Nano silica is added to the obtained organosilicone emulsion and stirred evenly to obtain an external waterproofing material.

[0052] The application of the above-mentioned concrete crack-resistant and seepage-proof agent includes the following steps:

[0053] S1. After mixing the internal waterproofing material and the concrete base material, pour the mixture and cure it at 18℃ for 28 days to obtain concrete blocks; the internal waterproofing material accounts for 1.2% of the total mass of the concrete base material.

[0054] S2. Apply an external waterproofing material evenly to the surface of the concrete blocks, with a coating amount of 0.5 kg / m². 2 After natural drying, crack-resistant and impermeable concrete blocks are produced.

[0055] In this embodiment, the coated rock wool fiber from Example 2 is used.

[0056] Example 5

[0057] A concrete crack-resistant and seepage-proof agent, comprising an internal seepage-proof material and an external seepage-proof material, by weight percentage,

[0058] The internal seepage prevention material includes the following raw materials: 8% sodium gluconate, 20% L-aspartic acid, 30% sodium sulfate, 15% sodium silicate, 12% coated rock wool fiber, and the balance is tetrasodium ethylenediaminetetraacetate;

[0059] The external waterproofing material comprises the following raw materials: 35% organosilane (n-octyltriethoxysilane), 6% emulsifier (Tween-80), 15% nano-silica, and the balance being deionized water. The nano-silica is composed of large-particle-size nano-silica (300-400nm) and small-particle-size nano-silica (50-100nm) in a 1:1 mass ratio.

[0060] The preparation method of the above-mentioned concrete crack-resistant and seepage-proof agent includes the following steps:

[0061] (1) Sodium gluconate, tetrasodium ethylenediaminetetraacetate, L-aspartic acid, sodium sulfate, sodium silicate and coated rock wool fiber are stirred and mixed to prepare an internal seepage-proof material;

[0062] (2) The organosilane, emulsifier and deionized water are stirred and emulsified at 65°C at a rate of 1000 r / min for 50 min. Nano silica is added to the obtained organosilicone emulsion and stirred evenly to obtain an external waterproofing material.

[0063] The application of the above-mentioned concrete crack-resistant and seepage-proof agent includes the following steps:

[0064] S1. After mixing the internal waterproofing material and the concrete base material, pour the mixture and cure it at 20℃ for 28 days to obtain concrete blocks; the internal waterproofing material accounts for 1% of the total mass of the concrete base material.

[0065] S2. Apply an external waterproofing material evenly to the surface of the concrete blocks, with a coating amount of 0.6 kg / m². 2 After natural drying, crack-resistant and impermeable concrete blocks are produced, as shown in the following image. Figure 1 As shown on the right, the surface is smooth and flat.

[0066] In this embodiment, the coated rock wool fiber from Example 2 is used.

[0067] Comparative Example 1

[0068] A concrete crack-resistant and seepage-proof agent is composed of an internal seepage-proof material. By mass percentage, the internal seepage-proof material includes the following raw materials: sodium gluconate 8%, L-aspartic acid 20%, sodium sulfate 30%, sodium silicate 15%, coated rock wool fiber 12%, and the balance is tetrasodium ethylenediaminetetraacetate.

[0069] The above-mentioned concrete crack-resistant and seepage-proof agent is prepared by mixing sodium gluconate, tetrasodium ethylenediaminetetraacetate, L-aspartic acid, sodium sulfate, sodium silicate and coated rock wool fiber to obtain an internal seepage-proof material, which is the concrete crack-resistant and seepage-proof agent.

[0070] The application of the above-mentioned concrete crack-resistant and seepage-proof agent includes the following steps: mixing the internal seepage-proof material and the concrete base material, pouring the mixture, and curing it at 20℃ for 28 days to obtain crack-resistant and seepage-proof concrete blocks, the appearance of which is shown in the figure. Figure 1 As shown on the left, cracks and pores can be seen; the amount of internal impermeable material accounts for 1% of the total mass of the concrete base material.

[0071] In this comparative example, the coated rock wool fiber from Example 2 was used.

[0072] Comparative Example 2

[0073] A concrete crack-resistant and seepage-proof agent, comprising an internal seepage-proof material and an external seepage-proof material, by weight percentage,

[0074] The internal seepage prevention material includes the following raw materials: sodium gluconate 8%, L-aspartic acid 20%, sodium sulfate 30%, sodium silicate 15%, rock wool fiber 12%, and the balance is tetrasodium ethylenediaminetetraacetate;

[0075] The external waterproofing material comprises the following raw materials: 35% organosilane (n-octyltriethoxysilane), 6% emulsifier (Tween-80), 15% nano-silica, and the balance being deionized water. The nano-silica is composed of large-particle-size nano-silica (300-400nm) and small-particle-size nano-silica (50-100nm) in a 1:1 mass ratio.

[0076] The preparation method of the above-mentioned concrete crack-resistant and seepage-proof agent is the same as the method in Example 5.

[0077] For the application of the above-mentioned concrete crack-resistant and seepage-proof agent, refer to the corresponding method in Example 5.

[0078] Comparative Example 3

[0079] A concrete crack-resistant and seepage-proof agent, comprising an internal seepage-proof material and an external seepage-proof material, by weight percentage,

[0080] The internal seepage prevention material includes the following raw materials: 8% sodium gluconate, 20% L-aspartic acid, 30% sodium sulfate, 15% sodium silicate, 12% coated rock wool fiber, and the balance is tetrasodium ethylenediaminetetraacetate;

[0081] The external waterproofing material includes the following raw materials: 35% organosilane (n-octyltriethoxysilane), 6% emulsifier (Tween-80), 15% small-particle-size nano silica (50-100nm), and the balance being deionized water.

[0082] The preparation method of the above-mentioned concrete crack-resistant and seepage-proof agent is the same as the method in Example 5.

[0083] For the application of the above-mentioned concrete crack-resistant and seepage-proof agent, refer to the corresponding method in Example 5.

[0084] In this comparative example, the coated rock wool fiber from Example 2 was used.

[0085] Comparative Example 4

[0086] A concrete crack-resistant and seepage-proof agent, comprising an internal seepage-proof material and an external seepage-proof material, by weight percentage,

[0087] The internal seepage-proof material includes the following raw materials: 20% L-aspartic acid, 30% sodium sulfate, 15% sodium silicate, 12% coated rock wool fiber, and the balance is tetrasodium ethylenediaminetetraacetate;

[0088] The external waterproofing material comprises the following raw materials: 35% organosilane (n-octyltriethoxysilane), 6% emulsifier (Tween-80), 15% nano-silica, and the balance being deionized water. The nano-silica is composed of large-particle-size nano-silica (300-400nm) and small-particle-size nano-silica (50-100nm) in a 1:1 mass ratio.

[0089] The preparation method of the above-mentioned concrete crack-resistant and seepage-proof agent is the same as the method in Example 5.

[0090] For the application of the above-mentioned concrete crack-resistant and seepage-proof agent, refer to the corresponding method in Example 5.

[0091] In this comparative example, the coated rock wool fiber from Example 2 was used.

[0092] Comparative Example 5

[0093] A concrete crack-resistant and seepage-proof agent, the same as in Example 5.

[0094] The preparation method of the above concrete crack-resistant and seepage-proof agent is the same as that in Example 5.

[0095] The application of the aforementioned concrete crack-resistant and seepage-proof agent includes the following steps: mixing the internal seepage-proof material, the external seepage-proof material, and the concrete base material, then pouring the mixture and curing it at 20℃ for 28 days to obtain crack-resistant and seepage-proof concrete blocks; wherein the dosage of the internal seepage-proof material accounts for 1% of the total mass of the concrete base material; based on the surface area of ​​the crack-resistant and seepage-proof concrete block, the dosage of the external seepage-proof material is 0.6 kg / m². 2 .

[0096] Quality Inspection

[0097] 1. Using the crack-resistant and impermeable concrete blocks from Examples 3-5 and Comparative Examples 1-5 as test samples, the impermeability strength of the samples was tested according to the standard GB / T18885-2020; the compressive strength of the samples was tested using a pressure tester (YAW 2000), with the pressurization speed set to 0.1 MPa / s; the sample size was controlled to be 70 mm × 80 mm × 60 mm. The specific test results are shown in Table 2.

[0098] Table 2 Compressive strength and impermeability

[0099]

[0100] As shown in Table 2:

[0101] (1) Compared with Example 5, the sample in Comparative Example 1 did not use external impermeable material, and its compressive strength and impermeability strength were significantly reduced;

[0102] (2) Compared with Example 5, the rock wool fiber was not coated in the sample of Comparative Example 2, and its compressive strength and impermeability were significantly reduced.

[0103] (3) Compared with Example 5, the sample in Comparative Example 4 did not have sodium gluconate added, and its compressive strength and impermeability were slightly reduced, which also shows that the addition of sodium gluconate has a positive effect on improving quality.

[0104] (4) The external seepage prevention material in Comparative Example 5 was added by direct mixing, which can also improve the quality of the sample, but the overall effect is not as good as that in Example 5.

[0105] 2. Using the crack-resistant and impermeable concrete blocks from Examples 3-5, Comparative Examples 1, 3, and 5 as test samples, the surface hydrophobicity was tested using a contact angle measuring instrument. The specific test results are shown in Table 3.

[0106] Table 3 Hydrophobicity

[0107]

[0108] As shown in Table 3:

[0109] (1) Compared with Example 5, the sample surface in Comparative Example 1 was not coated with an external waterproofing material, while the sample in Comparative Example 5 was added with an external waterproofing material by direct mixing, resulting in poor hydrophobic effect on the sample surface, which is not conducive to rapid drainage and rainwater can easily penetrate into the sample surface.

[0110] (2) Compared with Example 5, the samples in Comparative Example 3 were uniformly made of small-particle-size nano-silica, which made it difficult to form a micro-rough structure on the surface, and the hydrophobic effect was reduced.

[0111] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A concrete crack-resistant and seepage-proof agent, characterized in that, Includes internal and external waterproofing materials, expressed as a percentage by weight. The internal seepage-proof material includes the following raw materials: 5-10% sodium gluconate, 15-25% L-aspartic acid, 30-35% sodium sulfate, 15-20% sodium silicate, 10-15% coated rock wool fiber, and the balance being tetrasodium ethylenediaminetetraacetate. The external waterproofing material comprises the following raw materials: 30-40% organosilane, 5-8% emulsifier, 10-20% nano-silica, and the balance being deionized water; The preparation method of the coated rock wool fiber is as follows: rock wool fiber is added to calcium hydroxide solution and ultrasonically dispersed; then carbon dioxide is introduced until the solution pH is neutral; and then the coated rock wool fiber is obtained by separation and drying. The nano-silica is composed of large-particle-size nano-silica and small-particle-size nano-silica in a mass ratio of 1:1; wherein the particle size of the large-particle-size nano-silica is 300-400nm and the particle size of the small-particle-size nano-silica is 50-100nm.

2. The concrete crack-resistant and seepage-proof agent according to claim 1, characterized in that, The concentration of the calcium hydroxide solution is 1-1.5 g / L.

3. The concrete crack-resistant and seepage-proof agent according to claim 1, characterized in that, The organosilane is selected from n-octyltriethoxysilane and methyltriethoxysilane; the emulsifier is selected from Span-80 and Tween-80.

4. The method for preparing the concrete crack-resistant and seepage-proof agent according to any one of claims 1-3, characterized in that, Includes the following steps: (1) Sodium gluconate, tetrasodium ethylenediaminetetraacetate, L-aspartic acid, sodium sulfate, sodium silicate and coated rock wool fiber are stirred and mixed to prepare an internal seepage-proof material; (2) The organosilane, emulsifier and deionized water are stirred and emulsified. Nano-silica is added to the resulting organosilicone emulsion and stirred evenly to obtain an external waterproofing material.

5. The method for preparing the concrete crack-resistant and seepage-proof agent according to claim 4, characterized in that, In step (2), the temperature of stirring and emulsifying is 60-70℃, the stirring and emulsifying rate is 800-1200r / min, and the stirring and emulsifying time is 40-60min.

6. The application of a concrete crack-resistant and seepage-proof agent as described in any one of claims 1-3, characterized in that, Includes the following steps: S1. Mix the internal waterproofing material and concrete base material, pour the mixture, and cure it to obtain concrete blocks. S2. Apply an external waterproofing material evenly to the surface of the concrete block, and after natural drying, obtain crack-resistant and waterproof concrete blocks.

7. The application of the concrete crack-resistant and seepage-proof agent according to claim 6, characterized in that, In step S1, the curing temperature is 18-22℃ and the curing time is 28 days.

8. The application of the concrete crack-resistant and seepage-proof agent according to claim 6, characterized in that, In steps S1 and S2, the dosage of the internal waterproofing material accounts for 0.8-1.2% of the total mass of the concrete base material; the coating amount of the external waterproofing material is 0.5-0.8 kg / m³. 2 .

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