Highly viscous modified emulsified asphalt concrete and method for preparing the same

Abstract

The application relates to a high-viscosity modified emulsified asphalt concrete and a preparation method thereof, the high-viscosity modified emulsified asphalt concrete comprising the following raw materials in mass fractions: fine aggregate 200-400 parts, coarse aggregate 300-400 parts and modified emulsified asphalt 300-350 parts; the preparation method of the modified emulsified asphalt comprises the following steps: ethylene-vinyl acetate copolymer is added into water to prepare ethylene-vinyl acetate copolymer emulsion; the emulsified asphalt is added into the ethylene-vinyl acetate copolymer emulsion, mixed and stirred to prepare modified emulsified asphalt; and the high-viscosity modified emulsified asphalt concrete prepared by the application has good water resistance.

Description

Technical Field

[0001] The present application relates to the field of emulsified asphalt concrete, and in particular to a high-viscosity modified emulsified asphalt concrete and a preparation method thereof. Background Art

[0002] Emulsified asphalt is a liquid asphalt that is produced by the action of asphalt and emulsifiers under certain processes. It is an oil-in-water or oil-in-water liquid asphalt. Emulsified asphalt is usually made by diffusing high-temperature road asphalt into water through mechanical mixing and chemical stabilization, thereby liquefying it into a road construction material with very low viscosity and good fluidity at room temperature. It can be used at room temperature or with cold, wet stones. High-permeability emulsified asphalt concrete is made through mixing and stirring.

[0003] Due to the heavy rainfall in some parts of my country, the emulsified asphalt concrete surface layer is relatively thin, and there are gaps between coarse and fine aggregates, which easily leads to rainwater filling in the gaps. With the continuous erosion of rainwater, the bonding force between coarse and fine aggregates decreases, causing the gaps between coarse and fine aggregates to expand, resulting in the emulsified asphalt concrete becoming loose and pitted, and then causing water damage to the emulsified asphalt concrete. Summary of the Invention

[0004] In order to reduce the occurrence of water damage to emulsified asphalt concrete, the present application provides a high-viscosity modified emulsified asphalt concrete with high water resistance.

[0005] In the first aspect, the present application provides a high-viscosity modified emulsified asphalt concrete, which adopts the following technical solution:

[0006] A high-viscosity modified emulsified asphalt concrete comprises the following raw materials in parts by weight: 200-400 parts of fine aggregate, 300-400 parts of coarse aggregate, and 300-350 parts of modified emulsified asphalt. The preparation method of the modified emulsified asphalt comprises the following steps:

[0007] Ethylene-vinyl acetate copolymer is added into water to prepare ethylene-vinyl acetate copolymer emulsion; emulsified asphalt is added into the ethylene-vinyl acetate copolymer emulsion, mixed and stirred to prepare modified emulsified asphalt.

[0008] By adopting the above technical solution, first, the ethylene-vinyl acetate copolymer is in the form of tiny particles. When the ethylene-vinyl acetate copolymer is evenly distributed in the emulsified asphalt, the cross-linked structure formed by the two improves the bonding effect between coarse and fine aggregates and the emulsified asphalt, so that sufficient bonding strength can be generated between the emulsified asphalt and the coarse and fine aggregates, thereby improving the density between the emulsified asphalt and the coarse and fine aggregates, reducing water siltation and erosion, and further improving the water damage resistance and toughness of the concrete.

[0009] In addition, the ethylene-vinyl acetate copolymer structure contains more polar groups, which can better improve the bonding strength between emulsified asphalt and coarse and fine aggregates, and further enhance the concrete's resistance to water damage and toughness.

[0010] Preferably, in the preparation of the modified emulsified asphalt, the mass ratio of emulsified asphalt to ethylene-vinyl acetate copolymer is 1:(0.2-0.4).

[0011] By adopting the above technical solution, the mass ratio of emulsified asphalt and ethylene-vinyl acetate copolymer in the modified preparation of emulsified asphalt is controlled within the above range, which can effectively improve the bonding effect of emulsified asphalt and ethylene-vinyl acetate copolymer, thereby improving the concrete's resistance to water damage.

[0012] Preferably, the high-viscosity modified emulsified asphalt concrete further comprises 8-12 parts of polypropylene fibers.

[0013] By adopting the above technical solution, since there will be a large amount of free asphalt in the emulsified asphalt, the presence of free asphalt will reduce the bonding force between the emulsified asphalt and coarse and fine aggregates; therefore, the addition of polypropylene fiber will absorb the free asphalt in the emulsified asphalt, allowing the free asphalt to connect to the structural asphalt, thereby increasing the proportion of structural asphalt in the emulsified asphalt, allowing the emulsified asphalt to combine more effectively with the coarse and fine aggregates, enhancing the bonding force between the emulsified asphalt and the coarse and fine aggregates, and thus improving the water damage resistance and toughness of the concrete.

[0014] In addition, polypropylene fibers are evenly distributed in the emulsified asphalt concrete. The emulsified asphalt effectively combines the coarse and fine aggregates with the polypropylene fibers, playing a role of "reinforcement" and "bridging", thereby improving the toughness of the concrete.

[0015] Preferably, the polypropylene fiber in the high-viscosity modified emulsified asphalt concrete is prepared by modification, and the modification preparation method of the polypropylene fiber comprises the following steps:

[0016] Nano-silicon dioxide is dissolved in ethanol and stirred evenly to prepare a nano-silicon dioxide solution. Polypropylene fiber is added into the nano-silicon dioxide solution, heated for reaction, and filtered to prepare modified polypropylene fiber.

[0017] By adopting the above technical solution, since polypropylene fibers absorb and accumulate water, thereby destroying the bonding between emulsified asphalt and coarse and fine aggregates, the polypropylene fibers are modified and prepared, and nano-silicon dioxide is attached to the surface of the polypropylene fibers. Nano-silicon dioxide is hydrophobic, making the polypropylene fibers also highly hydrophobic, which can effectively reduce water damage to the structure of concrete, thereby enhancing the concrete's resistance to water damage.

[0018] In addition, nano-silica can effectively fill the gaps between emulsified asphalt and aggregate, improve the density of concrete, and thus enhance the concrete's resistance to water damage and toughness.

[0019] Preferably, in the modified preparation of the polypropylene fiber, the mass ratio of the polypropylene fiber to the nano-silicon dioxide is 1:(0.1-0.3).

[0020] By adopting the above technical solution, the mass ratio of polypropylene fiber and nano-silicon dioxide in the modified preparation of polypropylene fiber is controlled within the above range, which effectively enhances the water damage resistance and toughness of concrete.

[0021] Preferably, the nano-silicon dioxide is prepared by modification, and the modification preparation method of the nano-silicon dioxide comprises the following steps:

[0022] Alkyl polyglycoside is added into water to prepare an alkyl polyglycoside aqueous solution, nano silicon dioxide is added into the alkyl polyglycoside aqueous solution, stirred evenly, and then dried and filtered to prepare modified nano silicon dioxide.

[0023] By adopting the above technical solution, nano-silica is modified and prepared. After modification, the -CH3 group on the alkyl glycoside is introduced into the nano-silica, which enhances the hydrophobicity of the nano-silica, thereby enhancing the water damage resistance of the concrete; and the modified nano-silica side chains and polypropylene fiber molecular chains present a three-dimensional network structure, which enhances the adhesion between the emulsified asphalt and the coarse and fine aggregates, thereby improving the density of the concrete, and enhancing the water damage resistance and toughness of the concrete.

[0024] Preferably, the mass ratio of the nano-silica to the alkyl glycoside is 1:(0.8-1.2).

[0025] By adopting the above technical solution and controlling the mass ratio of nano-silica to alkyl glycoside within the above range, the -CH3 group on the alkyl glycoside can be better introduced into the nano-silica, thereby not only enhancing the water damage resistance of concrete, but also enhancing the toughness of concrete.

[0026] Preferably, the high-viscosity modified emulsified asphalt concrete further comprises 1-2 parts of a dispersant.

[0027] By adopting the above technical solution, dispersants are added to emulsified asphalt concrete, which improves the mixing uniformity of structural asphalt and coarse and fine aggregates in the emulsified asphalt and reduces the agglomeration of structural asphalt. At the same time, the smaller particle size of the dispersant can effectively fill the gaps between the emulsified asphalt and coarse and fine aggregates, thereby improving the density of the concrete, thereby not only enhancing the concrete's resistance to water damage, but also enhancing the toughness of the concrete.

[0028] Preferably, the dispersant is hydroxymethyl cellulose.

[0029] By adopting the above technical solution, hydroxymethyl cellulose improves the mixing uniformity of emulsified asphalt and aggregate, and hydroxymethyl cellulose has viscosity, which can effectively fill the gaps between emulsified asphalt and coarse and fine aggregates, and improve the density of concrete, thereby not only enhancing the concrete's resistance to water damage, but also enhancing the toughness of concrete.

[0030] In a second aspect, a method for preparing the high-viscosity modified emulsified asphalt concrete as described in the first aspect comprises the following steps:

[0031] The fine aggregate, coarse aggregate and emulsified asphalt are mixed and stirred evenly to prepare high-viscosity modified emulsified asphalt concrete.

[0032] In summary, this application includes at least one of the following beneficial technical effects:

[0033] 1. Ethylene-vinyl acetate copolymer is in the form of tiny particles, evenly distributed in the emulsified asphalt. The cross-linked structure formed by the two improves the bonding between coarse and fine aggregates and the emulsified asphalt, creating sufficient bond strength between the emulsified asphalt and the coarse and fine aggregates, thereby improving the concrete's water resistance and toughness. The ethylene-vinyl acetate copolymer structure contains a large number of polar groups, which can enhance the bonding between the emulsified asphalt and the coarse and fine aggregates, improve the stability and density of the concrete, and further enhance the concrete's water resistance and toughness.

[0034] 2. The addition of polypropylene fibers absorbs the free asphalt in the emulsified asphalt, allowing the free asphalt to connect to the structural asphalt, increasing the proportion of structural asphalt in the emulsified asphalt. This allows the emulsified asphalt to more effectively combine with coarse and fine aggregates, strengthening the bonding between the emulsified asphalt and the coarse and fine aggregates, thereby improving the concrete's resistance to water damage and toughness. In addition, the polypropylene fibers are evenly distributed in the emulsified asphalt concrete, effectively combining the coarse and fine aggregates with the polypropylene fibers through the emulsified asphalt, playing a "reinforcement" and "bridging" role, thereby improving the toughness of the concrete.

[0035] 3. Nano-silica has been modified to introduce -CH3 groups on alkyl glycosides, which enhances the hydrophobicity of nano-silica and thus strengthens the water damage resistance of concrete; and the modified nano-silica side chains and polypropylene fiber molecular chains present a three-dimensional network structure, which enhances the bonding force between emulsified asphalt and coarse and fine aggregates, thereby enhancing the water damage resistance and toughness of concrete. DETAILED DESCRIPTION

[0036] The embodiments of the present application disclose a high-viscosity modified emulsified asphalt concrete. The present application is further described in detail below in combination with the embodiments and comparative examples. The raw materials involved in the present application can be obtained commercially, among which ethylene-vinyl acetate copolymer is provided by Wuhan Jiyesheng Chemical Co., Ltd.

[0037] Example 1

[0038] A high-viscosity modified emulsified asphalt concrete comprises the following raw materials in parts by weight: 300 g of fine aggregate, 300 g of coarse aggregate, and 500 g of modified emulsified asphalt. The preparation method of the modified emulsified asphalt comprises the following steps:

[0039] 150 g of ethylene-vinyl acetate copolymer was added to 1000 mL of water, and the mixture was stirred evenly to prepare an ethylene-vinyl acetate copolymer emulsion; 500 g of emulsified asphalt was added to the ethylene-vinyl acetate copolymer emulsion, and the mixture was stirred to prepare a modified emulsified asphalt.

[0040] The preparation method of high-viscosity modified emulsified asphalt concrete comprises the following steps:

[0041] The fine aggregate, coarse aggregate and emulsified asphalt are mixed and stirred evenly to prepare high-viscosity modified emulsified asphalt concrete.

[0042] Example 2

[0043] A high-viscosity modified emulsified asphalt concrete comprises the following raw materials in parts by weight: 3000 g of fine aggregate, 3500 g of coarse aggregate, and 3250 g of modified emulsified asphalt. The preparation method of the modified emulsified asphalt comprises the following steps:

[0044] 100 g of ethylene-vinyl acetate copolymer was added to 1000 mL of water, and the mixture was stirred evenly to prepare an ethylene-vinyl acetate copolymer emulsion; 500 g of emulsified asphalt was added to the ethylene-vinyl acetate copolymer emulsion, and the mixture was stirred to prepare a modified emulsified asphalt.

[0045] The preparation method of high-viscosity modified emulsified asphalt concrete comprises the following steps:

[0046] The fine aggregate, coarse aggregate and emulsified asphalt are mixed and stirred evenly to prepare high-viscosity modified emulsified asphalt concrete.

[0047] Example 3

[0048] A high-viscosity modified emulsified asphalt concrete comprises the following raw materials in parts by weight: 2000 g of fine aggregate, 4000 g of coarse aggregate, and 3500 g of modified emulsified asphalt. The preparation method of the modified emulsified asphalt comprises the following steps:

[0049] 200 g of ethylene-vinyl acetate copolymer was added to 1000 mL of water, and the mixture was stirred evenly to prepare an ethylene-vinyl acetate copolymer emulsion; 500 g of emulsified asphalt was added to the ethylene-vinyl acetate copolymer emulsion, and the mixture was stirred to prepare a modified emulsified asphalt.

[0050] The preparation method of high-viscosity modified emulsified asphalt concrete comprises the following steps:

[0051] The fine aggregate, coarse aggregate and emulsified asphalt are mixed and stirred evenly to prepare high-viscosity modified emulsified asphalt concrete.

[0052] Example 4

[0053] The difference between Example 4 and Example 1 is that in the preparation of the modified emulsified asphalt, the total mass of the emulsified asphalt and the ethylene-vinyl acetate copolymer is constant, and the mass ratio of the emulsified asphalt to the ethylene-vinyl acetate copolymer is 1:0.1.

[0054] Example 5

[0055] The difference between Example 5 and Example 1 is that in the preparation of the modified emulsified asphalt, the total mass of the emulsified asphalt and the ethylene-vinyl acetate copolymer is constant, and the mass ratio of the emulsified asphalt to the ethylene-vinyl acetate copolymer is 1:0.5.

[0056] Example 6

[0057] The difference between Example 6 and Example 1 is that the high-viscosity modified emulsified asphalt concrete further includes 100g of polypropylene fiber.

[0058] Example 7

[0059] The difference between Example 7 and Example 6 is that: 80g of polypropylene fiber.

[0060] Example 8

[0061] The difference between Example 8 and Example 6 is that: 120g of polypropylene fiber.

[0062] Example 9

[0063] The difference between Example 9 and Example 6 is that the polypropylene fiber in the high-viscosity modified emulsified asphalt concrete is prepared by modification, and the modification preparation method of the polypropylene fiber includes the following steps:

[0064] 20 g of nano-silica was added to 1000 mL of ethanol and stirred evenly to prepare a nano-silica solution. 100 g of polypropylene fiber was added to the nano-silica solution, heated to 60° C., and subjected to ultrasonic treatment. After stirring and standing, the solution was filtered to obtain modified polypropylene fiber.

[0065] Example 10

[0066] The difference between Example 10 and Example 9 is that in the modified preparation of the polypropylene fiber, the total mass of the polypropylene fiber and the nano-silica is constant, and the mass ratio of the polypropylene fiber to the nano-silica is 1:0.1.

[0067] Example 11

[0068] The difference between Example 11 and Example 9 is that in the modified preparation of the polypropylene fiber, the total mass of the polypropylene fiber and the nano-silica is constant, and the mass ratio of the polypropylene fiber to the nano-silica is 1:0.3.

[0069] Example 12

[0070] The difference between Example 12 and Example 9 is that in the modified preparation of polypropylene fiber, the total mass of polypropylene fiber and nano-silica is constant, and the mass ratio of polypropylene fiber to nano-silica is 1:0.05.

[0071] Example 13

[0072] The difference between Example 13 and Example 9 is that in the modified preparation of polypropylene fiber, the total mass of polypropylene fiber and nano-silica is constant, and the mass ratio of polypropylene fiber to nano-silica is 1:0.35.

[0073] Example 14

[0074] The difference between Example 14 and Example 9 is that the nano-silicon dioxide is prepared by modification. The modification preparation method of the nano-silicon dioxide comprises the following steps:

[0075] 20 g of alkyl glycoside was added into 200 mL of water to prepare an alkyl glycoside aqueous solution, 20 g of nano-silica was added into the alkyl glycoside aqueous solution, the mixture was stirred evenly, and then dried and filtered to prepare modified nano-silica.

[0076] Example 15

[0077] The difference between Example 15 and Example 14 is that in the modified preparation of nano-silica, the total mass of nano-silica and alkyl glycoside is constant, and the mass ratio of nano-silica to alkyl glycoside is 1:0.8.

[0078] Example 16

[0079] The difference between Example 16 and Example 14 is that in the modified preparation of nano-silica, the total mass of nano-silica and alkyl glycoside is constant, and the mass ratio of nano-silica to alkyl glycoside is 1:1.2.

[0080] Example 17

[0081] The difference between Example 17 and Example 14 is that in the modified preparation of nano-silica, the total mass of nano-silica and alkyl glycoside is constant, and the mass ratio of nano-silica to alkyl glycoside is 1:0.6.

[0082] Example 18

[0083] The difference between Example 18 and Example 14 is that in the modified preparation of nano-silica, the total mass of nano-silica and alkyl glycoside is constant, and the mass ratio of nano-silica to alkyl glycoside is 1:1.4.

[0084] Example 19

[0085] The difference between Example 19 and Example 14 is that the high-viscosity modified emulsified asphalt concrete also includes 15g of dispersant, wherein the dispersant is hydroxymethyl cellulose.

[0086] Example 20

[0087] The difference between Example 20 and Example 19 is that 10 g of dispersant is contained in the high-viscosity modified emulsified asphalt concrete, wherein the dispersant is hydroxymethyl cellulose.

[0088] Example 21

[0089] The difference between Example 21 and Example 19 is that 20 g of dispersant is contained in the high-viscosity modified emulsified asphalt concrete, wherein the dispersant is hydroxymethyl cellulose.

[0090] Comparative Example 1

[0091] The difference between Comparative Example 1 and Example 1 is that the emulsified asphalt in the high-viscosity modified emulsified asphalt concrete is prepared without modification.

[0092] Comparative Example 2

[0093] The difference between Comparative Example 2 and Example 8 is that steel fiber is used instead of polypropylene fiber.

[0094] Performance testing:

[0095] Sampling: The concrete prepared in Examples 1-21 and Comparative Examples 1-2 was taken as test samples and tested after curing for 28 days. The test samples were standard cubic specimens of 150 mm × 150 mm × 150 mm.

[0096] Water erosion resistance test: According to the anti-permeability grade specified in GB50164 "Concrete Quality Control Standard", the maximum water pressure that concrete can withstand when tested according to the standard test method is shown in Table 1.

[0097] Toughness test: Refer to GB / T50081-2019 "Test methods for mechanical properties of ordinary concrete" to test the splitting tensile strength of the sample, and record the test results in Table 1.

[0098] Table 1

[0099] sample Osmotic pressure / MPa Splitting tensile strength / MPa Example 1 1.22 3.9 Example 2 1.16 3.6 Example 3 1.15 3.6 Example 4 1.08 3.0 Example 5 1.07 2.9 Example 6 1.51 4.6 Example 7 1.47 4.3 Example 8 1.47 4.3 Example 9 1.89 5.6 Example 10 1.84 5.3 Example 11 1.85 5.3 Example 12 1.80 4.9 Example 13 1.80 5.0 Example 14 2.05 6.2 Example 15 2.01 6.0 Example 16 2.00 6.0 Example 17 1.95 5.8 Example 18 1.96 5.8 Example 19 2.26 7.0 Example 20 2.22 6.8 Example 21 2.23 6.7 Comparative Example 1 1.05 2.5 Comparative Example 2 1.26 4.4

[0100] According to Table 1, the concrete of Examples 1-3 has a penetration pressure of 1.15-1.22 MPa and a splitting tensile strength of 3.6-3.9 MPa. It can be seen that the concrete of Examples 1-3 not only has good water damage resistance, but also has good toughness.

[0101] According to Table 1, the concrete of Example 4 has a penetration pressure of 1.08 MPa and a splitting tensile strength of 3.0 MPa, while the concrete of Example 1 has a penetration pressure of 1.22 MPa and a splitting tensile strength of 3.9 MPa. In comparison, the penetration pressure and splitting tensile strength of the concrete of Example 4 are lower than those of the concrete of Example 1. The reason is that the amount of ethylene-vinyl acetate copolymer is reduced, which makes the bonding effect between coarse and fine aggregates and emulsified asphalt worse, thereby resulting in a decrease in the concrete's resistance to water damage; and the reduction in the amount of ethylene-vinyl acetate copolymer reduces the stability and density of the concrete, thereby reducing the toughness of the concrete.

[0102] According to Table 1, the concrete penetration pressure of Example 5 is 1.07 MPa, and the splitting tensile strength is 2.9 MPa. The concrete penetration pressure of Example 1 is 1.22 MPa, and the splitting tensile strength is 3.9 MPa. In comparison, the concrete penetration pressure and splitting tensile strength of Example 5 are lower than those of Example 1. The reason is that the amount of ethylene-vinyl acetate copolymer increases and the amount of emulsified asphalt decreases, which makes the bonding effect between coarse and fine aggregates and emulsified asphalt worse, thereby resulting in a decrease in the concrete's resistance to water damage; and the reduction in the amount of emulsified asphalt reduces the stability and density of the concrete, thereby reducing the toughness of the concrete.

[0103] Table 1 shows that the concrete of Examples 6-8 has a penetration pressure of 1.47-1.51 MPa and a splitting tensile strength of 4.3-4.6 MPa. The concrete of Example 1 has a penetration pressure of 1.22 MPa and a splitting tensile strength of 3.9 MPa. In comparison, the concrete of Examples 6-8 has higher penetration pressure and splitting tensile strength than the concrete of Example 1. This is because the addition of polypropylene fibers absorbs emulsified asphalt, increasing the proportion of structural emulsified asphalt and reducing the proportion of free emulsified asphalt. Polypropylene fibers strengthen the bond between emulsified asphalt and coarse and fine aggregates, thereby improving the concrete's resistance to water damage. Polypropylene fibers are evenly distributed in the emulsified asphalt concrete. The emulsified asphalt effectively binds the coarse and fine aggregates to the polypropylene fibers, acting as a "reinforcement" and "bridging" agent, thereby enhancing the concrete's toughness.

[0104] According to Table 1, the concrete penetration pressure of Examples 9-11 is 1.84-1.89 MPa, and the splitting tensile strength is 5.3-5.6 MPa. The concrete penetration pressure of Example 6 is 1.51 MPa, and the splitting tensile strength is 4.6 MPa. In comparison, the concrete penetration pressure and splitting tensile strength of Examples 9-11 are higher than those of the concrete in Example 6. The reason is that the polypropylene fiber is prepared through modification, and nano-silica will adhere to the surface of the polypropylene fiber. Nano-silica is hydrophobic, which makes the polypropylene fiber also have strong hydrophobicity, which can effectively reduce the structural damage of water to the polypropylene fiber, thereby enhancing the water damage resistance of the concrete. In addition, nano-silica can effectively fill the gaps between the emulsified asphalt and the coarse and fine aggregates, improve the density of the concrete, and thus enhance the toughness of the concrete.

[0105] According to Table 1, the concrete penetration pressure of Example 12 is 1.80 MPa, and the splitting tensile strength is 4.9 MPa. The concrete penetration pressure of Example 9 is 1.89 MPa, and the splitting tensile strength is 5.6 MPa. In comparison, the concrete penetration pressure and splitting tensile strength of Example 12 are lower than those of the concrete of Example 9. The reason is that the amount of nano-silica is relatively small, which makes the hydrophobic modification effect of the polypropylene fiber worse, thereby making the water erosion resistance of the concrete worse. Due to the reduction in the amount of nano-silica, the density of the concrete decreases, thereby reducing the toughness of the concrete.

[0106] According to Table 1, the concrete penetration pressure of Example 13 is 1.80 MPa, and the splitting tensile strength is 5.0 MPa. The concrete penetration pressure of Example 9 is 1.89 MPa, and the splitting tensile strength is 5.6 MPa. In comparison, the concrete penetration pressure and splitting tensile strength of Example 13 are lower than those of the concrete of Example 9. The reason is that the amount of nano-silica is too high and the amount of polypropylene fiber is too low, which makes the hydrophobic modification effect of the polypropylene fiber worse, thereby making the water erosion resistance of the concrete worse. Due to the reduction in the amount of polypropylene fiber, the toughness of the concrete is reduced.

[0107] According to Table 1, the concrete penetration pressure of Examples 14-16 is 2.00-2.05 MPa, and the splitting tensile strength is 6.0-6.2 MPa. The concrete penetration pressure of Example 9 is 1.89 MPa, and the splitting tensile strength is 5.6 MPa. In comparison, the concrete penetration pressure and splitting tensile strength of Examples 14-16 are higher than that of the concrete in Example 9. The reason is that the nano-silica is modified and prepared by introducing the -CH3 group on the alkyl glycoside, which enhances the hydrophobicity of the nano-silica, thereby enhancing the water resistance of the concrete; and the modified nano-silica side chains and polypropylene fiber molecular chains present a three-dimensional network structure, which enhances the adhesion between the emulsified asphalt and the coarse and fine aggregates, thereby enhancing the toughness of the concrete.

[0108] According to Table 1, the concrete of Example 17 has a penetration pressure of 1.95 MPa and a splitting tensile strength of 5.8 MPa, while the concrete of Example 14 has a penetration pressure of 2.05 MPa and a splitting tensile strength of 6.2 MPa. In comparison, the penetration pressure and splitting tensile strength of the concrete of Example 17 are lower than those of the concrete of Example 14. The reason is that the amount of alkyl glycoside is relatively small, which makes the hydrophobic modification effect of nano-silica worse, thereby reducing not only the water damage resistance of the concrete, but also the toughness of the concrete.

[0109] According to Table 1, the concrete penetration pressure of Example 18 is 1.96 MPa, and the splitting tensile strength is 5.8 MPa. The concrete penetration pressure of Example 14 is 2.05 MPa, and the splitting tensile strength is 6.2 MPa. In comparison, the concrete penetration pressure and splitting tensile strength of Example 18 are lower than those of Example 14. The reason is that the amount of nano-silica is too small, which makes the hydrophobic modification effect of nano-silica worse, thereby reducing the water erosion resistance of the concrete. In addition, the amount of nano-silica is too small, which reduces the toughness of the concrete.

[0110] According to Table 1, the concrete penetration pressure of Examples 19-21 is 2.23-2.26 MPa, and the splitting tensile strength is 6.7-7.0 MPa. The concrete penetration pressure of Example 14 is 2.05 MPa, and the splitting tensile strength is 6.2 MPa. In comparison, the concrete penetration pressure and splitting tensile strength of Examples 19-21 are higher than that of the concrete of Example 14. The reason is that hydroxymethyl cellulose improves the mixing uniformity of emulsified asphalt and coarse and fine aggregates, and hydroxymethyl cellulose has viscosity, which can effectively fill the gaps between emulsified asphalt and coarse and fine aggregates, thereby improving the density of concrete, thereby enhancing not only the water damage resistance of concrete, but also the toughness of concrete.

[0111] According to Table 1, the concrete penetration pressure of Comparative Example 1 is 1.05 MPa, and the splitting tensile strength is 2.5 MPa. The concrete penetration pressure of Example 1 is 1.22 MPa, and the splitting tensile strength is 3.9 MPa. In comparison, the concrete penetration pressure and splitting tensile strength of Comparative Example 1 are lower than those of Example 1. The reason is that the absence of ethylene-vinyl acetate copolymer-modified emulsified asphalt deteriorates the bonding between coarse and fine aggregates and the emulsified asphalt, thereby reducing the concrete's resistance to water damage; and the absence of ethylene-vinyl acetate copolymer reduces the stability and density of the concrete, thereby reducing the concrete toughness.

[0112] According to Table 1, the concrete of Comparative Example 2 has a penetration pressure of 1.26 MPa and a splitting tensile strength of 4.4 MPa, while the concrete of Example 8 has a penetration pressure of 1.51 MPa and a splitting tensile strength of 4.6 MPa. In comparison, the penetration pressure and splitting tensile strength of the concrete of Comparative Example 2 are lower than those of the concrete of Example 8. The reason is that the steel fiber cannot effectively reduce the number and size of native cracks, thereby reducing the toughness of the concrete. Polypropylene fiber has excellent dispersibility in concrete and the bonding between polypropylene fiber and coarse and fine aggregates and emulsified asphalt is good, which makes the concrete more resistant to water erosion. However, the bonding between steel fiber and coarse and fine aggregates is poor, resulting in poor water erosion resistance of the concrete, thereby reducing the water erosion resistance of the concrete.

Claims

1. A high-viscosity modified emulsified asphalt concrete, characterized by: The raw materials include the following parts by weight: 200-400 parts of fine aggregate, 300-400 parts of coarse aggregate, and 300-350 parts of modified emulsified asphalt; the preparation method of the modified emulsified asphalt includes the following steps: Adding ethylene-vinyl acetate copolymer to water to prepare ethylene-vinyl acetate copolymer emulsion; adding emulsified asphalt to the ethylene-vinyl acetate copolymer emulsion, mixing and stirring to prepare modified emulsified asphalt; In the preparation of the modified emulsified asphalt, the mass ratio of emulsified asphalt to ethylene-vinyl acetate copolymer is 1:(0.2-0.4); The raw materials also include 8-12 parts of polypropylene fiber; The polypropylene fiber is prepared by modification. The modification preparation method of the polypropylene fiber comprises the following steps: dissolving nano-silicon dioxide in ethanol, stirring evenly to prepare a nano-silicon dioxide solution, adding polypropylene fiber to the nano-silicon dioxide solution, heating to react, and filtering to prepare modified polypropylene fiber; In the modified preparation of the polypropylene fiber, the mass ratio of the polypropylene fiber to the nano-silicon dioxide is 1: (0.1-0.3); The nano-silica is prepared by modification, and the modification preparation method of the nano-silica comprises the following steps: adding alkyl glycoside to water to prepare an alkyl glycoside aqueous solution, adding nano-silica to the alkyl glycoside aqueous solution, stirring evenly, filtering and drying to obtain modified nano-silica; In the modified preparation of the nano-silica, the mass ratio of the nano-silica to the alkyl glycoside is 1:(0.8-1.2).

2. The high-viscosity modified emulsified asphalt concrete according to claim 1, characterized in that: Also includes 1-2 parts of dispersant.

3. The high-viscosity modified emulsified asphalt concrete according to claim 2, characterized in that: The dispersant is hydroxymethyl cellulose.

4. A method for preparing the high-viscosity modified emulsified asphalt concrete according to claim 1, characterized in that: The steps include: Fine aggregate, coarse aggregate and modified emulsified asphalt are mixed and stirred evenly to prepare high-viscosity modified emulsified asphalt concrete.