Long-service-life asphalt mixture based on addition of basalt fibers as well as preparation method and application of long-service-life asphalt mixture

Abstract

The invention relates to the technical field of asphalt mixtures, in particular to a long-service-life asphalt mixture based on addition of basalt fibers as well as a preparation method and application of the long-service-life asphalt mixture. The long-life asphalt mixture added with the basalt fibers is prepared from 50 to 60 parts of asphalt, 1 to 5 parts of the basalt fibers, 450 to 500 parts of aggregate, 10 to 20 parts of filler and 1 to 3 parts of rattan bark powder. The filler and the rattan bark powder are matched for use, so that the adhesive force between the asphalt and the aggregate can be remarkably improved, a firmer bonding interface is formed, the asphalt can better permeate into the surface of the aggregate, a compact wrapping layer is formed, and the overall strength and wear resistance of the mixture are improved. In conclusion, the asphalt mixture has excellent water permeability and wear resistance, and the service life of the asphalt mixture can be prolonged.

Description

Technical Field

[0001] The present invention relates to the technical field of asphalt mixtures, and in particular to a long-life asphalt mixture based on the addition of basalt fibers, and a preparation method and application thereof. Background Art

[0002] With the continuous increase in traffic volume and vehicle loads, the requirements for road materials are becoming increasingly stringent. Asphalt, a viscoelastic-plastic material with excellent adhesion and a certain degree of elasticity, is a key component of asphalt mixtures. While traditional asphalt mixtures offer good workability and a certain degree of durability, their service life and performance often fail to meet the demands of modern transportation under complex conditions such as long-term heavy loads, high and low temperatures, and water damage. Therefore, the development of a long-lasting, high-performance asphalt mixture is particularly important.

[0003] Basalt fiber, primarily composed of silicon-oxygen tetrahedra and aluminum-oxygen tetrahedra connected by shared oxygen vertices to form a continuous linear structure, is a new type of high-performance fiber material widely used in road construction due to its excellent properties, including high strength, high modulus, corrosion resistance, and wear resistance. However, while the addition of basalt fiber alone can improve the performance of the mixture to a certain extent, it often fails to achieve the desired overall effect and is also costly to produce.

[0004] Therefore, how to regulate the composition design of asphalt mixture to effectively improve the water permeability, wear resistance and mechanical properties of asphalt mixture has become a key issue that needs to be solved urgently. Summary of the Invention

[0005] To overcome the shortcomings of existing technologies, one of the objectives of the present invention is to provide a long-life asphalt mixture based on the addition of basalt fiber. By innovatively incorporating fillers and rattan bark powder, the present invention significantly improves the permeability and wear resistance of the asphalt mixture, meeting the high demands placed on road materials in modern transportation.

[0006] The second purpose of the present invention is to provide a method for preparing a long-life asphalt mixture based on the addition of basalt fiber. The preparation method and application also have the advantages of environmental protection and sustainability, and are of great significance for promoting the innovation and development of road engineering materials.

[0007] The third object of the present invention is to provide an application of a long-life asphalt mixture based on the addition of basalt fibers.

[0008] One of the purposes of the present invention is achieved by the following technical solution:

[0009] Long-life asphalt mixture based on the addition of basalt fiber, including 50-60 parts of asphalt, 1-5 parts of basalt fiber, 450-500 parts of aggregate, 10-20 parts of filler, and 1-3 parts of rattan bark powder;

[0010] Furthermore, the preparation process of the filler is as follows:

[0011] (1) Pre-treating mullite whiskers;

[0012] (2) adding a mixed solution of magnesium nitrate and ferric nitrate to a sodium hydroxide solution, stirring and mixing to obtain a mixed solution;

[0013] (3) adding the mullite whiskers pretreated in step (1) into the mixed solution of step (2), stirring and mixing them evenly, and then performing a hydrothermal reaction to obtain the product.

[0014] Furthermore, the pretreatment process of step (1) is as follows: adding mullite whiskers into a mixed solvent and heating the mixture, and then filtering, washing and drying the reaction solution to obtain the product.

[0015] Furthermore, the mixed solvent is prepared from anhydrous ethanol and acetone in a volume ratio of 1:(1-2), the heating temperature is 75-85° C., and the heating time is 3-5 hours.

[0016] Furthermore, in step (2), the mass ratio of the magnesium nitrate, ferric nitrate, sodium hydroxide and water is 1:(0.4-0.8):(0.5-0.9):(45-55).

[0017] Furthermore, in step (3), the mass ratio of the pretreated mullite whiskers to the magnesium nitrate in the mixed solution obtained in step (2) is 1:(3-8).

[0018] Furthermore, in step (3), the temperature of the hydrothermal reaction is 110-120° C., and the time is 24-30 h.

[0019] Furthermore, the diameter of the mullite whisker is 0.2-3 μm, and the length is 5-200 μm; the particle size of the aggregate is 0.5-2.5 mm.

[0020] Furthermore, the length of the basalt fiber is 10-25 mm.

[0021] Furthermore, the asphalt is 70# Grade A asphalt.

[0022] The second object of the present invention is achieved by adopting the following technical solution:

[0023] The preparation method of long-life asphalt mixture based on adding basalt fiber includes the following steps:

[0024] a. According to the above parts by weight, the basalt fiber, aggregate, filler, rattan bark powder was stirred and mixed to obtain a mixed material;

[0025] b. Add the above mixture into asphalt, heat at 160-170℃ and stir evenly.

[0026] The third object of the present invention is achieved by adopting the following technical solution:

[0027] Application of long-life asphalt mixture based on the addition of basalt fiber in the field of road engineering construction.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] 1. The present invention provides a long-life asphalt mixture based on the addition of basalt fiber. The mixture innovatively adds a filler, which is made from mullite whiskers. The pretreated mullite whiskers give the filler a larger specific surface area, and then the filler is compounded with magnesium nitrate and ferric nitrate through a hydrothermal method to produce the filler. The combination of the filler and rattan bark powder of the present invention improves the water absorption rate of the asphalt mixture and enhances the water permeability of the asphalt mixture. The addition of the filler can significantly improve the adhesion between the asphalt and the aggregate, forming a more solid bonding interface, allowing the asphalt to better penetrate the aggregate surface, forming a tight coating, thereby improving the overall strength and wear resistance of the mixture.

[0030] 2. By adding basalt fiber to the asphalt mixture, the present invention increases the mixture strength, significantly improves the durability of the pavement, and extends the service life of the pavement. Basalt fiber has the characteristics of high strength, high corrosion resistance, and good dispersibility, and can effectively enhance the crack resistance, fatigue resistance, and water damage resistance of asphalt pavements. The preparation method of the present invention is simple, easy to implement, and low-cost, making it suitable for large-scale promotion and application. DETAILED DESCRIPTION

[0031] Below, in conjunction with specific embodiments, the present invention is further described. It should be noted that, under the premise of no conflict, the various embodiments described below or the various technical features can be arbitrarily combined to form new embodiments. Specific conditions not specified in the embodiments are carried out according to conventional conditions or conditions recommended by the manufacturer. Reagents or instruments used, unless otherwise specified, are conventional products obtained through commercial channels.

[0032] In the embodiments and comparative examples of the present invention, the length of the basalt fiber is 10-25 mm; the asphalt is 70# Grade A asphalt; the diameter of the mullite whisker is 0.2-3 μm and the length is 5-200 μm; and the particle size of the aggregate is 0.5-2.5 mm.

[0033] Example 1

[0034] Long-life asphalt mixture based on the addition of basalt fiber, including 55 parts of asphalt, 3 parts of basalt fiber, 470 parts of aggregate, 18 parts of filler, and 2 parts of rattan bark powder;

[0035] The preparation process of the filler is as follows:

[0036] (1) adding mullite whiskers into a mixed solvent (prepared by mixing anhydrous ethanol and acetone in a volume ratio of 1:1), heating at 80°C for 4 hours, and then filtering, washing and drying the reaction solution to obtain pretreated mullite whiskers;

[0037] (2) according to the mass ratio of magnesium nitrate, ferric nitrate, sodium hydroxide and water being 1:0.6:0.7:50, taking one half of the above total amount of water, adding magnesium nitrate and ferric nitrate thereto to obtain a mixed solution of magnesium nitrate and ferric nitrate, then adding sodium hydroxide to the remaining water to obtain a sodium hydroxide solution, and under a nitrogen atmosphere, stirring and mixing the mixed solution and the sodium hydroxide solution to obtain a mixed solution;

[0038] (3) adding the mullite whiskers pretreated in step (1) to the mixed solution of step (2), wherein the mass ratio of the pretreated mullite whiskers to the magnesium nitrate in the mixed solution obtained in step (2) is 1:5; stirring for 30 minutes under a nitrogen atmosphere, adding the whiskers to a reactor, performing a hydrothermal reaction at 115° C. for 28 hours, centrifuging the reaction solution at 10,000 rpm for 10 minutes, and washing the precipitate with deionized water three times to obtain the product.

[0039] The rattan bark powder comprises the following preparation steps: taking the outer bark of healthy Celastrus orbiculatus, drying it, then grinding it in a high-energy ball mill, and spray drying it to obtain the rattan bark powder with a particle size of 100-200 nm.

[0040] This embodiment also provides a method for preparing a long-life asphalt mixture based on the addition of basalt fiber, comprising the following steps:

[0041] a. According to the above parts by weight, the basalt fiber, aggregate, filler, rattan bark powder was stirred and mixed to obtain a mixed material;

[0042] b. Add the above mixture into asphalt, heat at 165℃ and stir evenly.

[0043] Example 2

[0044] Long-life asphalt mixture based on the addition of basalt fiber, including 50 parts of asphalt, 1 part of basalt fiber, 450 parts of aggregate, 10 parts of filler, and 1 part of rattan bark powder;

[0045] The preparation process of the filler is as follows:

[0046] (1) adding mullite whiskers into a mixed solvent (prepared by mixing anhydrous ethanol and acetone in a volume ratio of 1:1.5), heating at 75°C for 5 hours, and then filtering, washing and drying the reaction solution to obtain pretreated mullite whiskers;

[0047] (2) according to the mass ratio of magnesium nitrate, ferric nitrate, sodium hydroxide and water being 1:0.4:0.5:45, taking half of the above total amount of water and adding magnesium nitrate and ferric nitrate thereto to obtain a mixed solution of magnesium nitrate and ferric nitrate, then adding sodium hydroxide to the remaining water to obtain a sodium hydroxide solution, and under a nitrogen atmosphere, stirring and mixing the mixed solution and the sodium hydroxide solution to obtain a mixed solution;

[0048] (3) adding the mullite whiskers pretreated in step (1) to the mixed solution of step (2), wherein the mass ratio of the pretreated mullite whiskers to the magnesium nitrate in the mixed solution obtained in step (2) is 1:3; stirring for 30 minutes under a nitrogen atmosphere, adding the whiskers to a reactor, performing a hydrothermal reaction at 110° C. for 30 hours, centrifuging the reaction solution at 10,000 rpm for 10 minutes, and washing the precipitate with deionized water three times to obtain the product.

[0049] The rattan bark powder comprises the following preparation steps: taking the outer bark of healthy Celastrus orbiculatus, drying it, then grinding it in a high-energy ball mill, and spray drying it to obtain the rattan bark powder with a particle size of 100-200 nm.

[0050] This embodiment also provides a method for preparing a long-life asphalt mixture based on the addition of basalt fiber, comprising the following steps:

[0051] a. According to the above parts by weight, the basalt fiber, aggregate, filler, rattan bark powder was stirred and mixed to obtain a mixed material;

[0052] b. Add the above mixture into asphalt, heat at 160℃ and stir evenly.

[0053] Example 3

[0054] Long-life asphalt mixture based on the addition of basalt fiber, including 60 parts of asphalt, 5 parts of basalt fiber, 500 parts of aggregate, 20 parts of filler, and 3 parts of rattan bark powder;

[0055] The preparation process of the filler is as follows:

[0056] (1) adding mullite whiskers into a mixed solvent (prepared by mixing anhydrous ethanol and acetone in a volume ratio of 1:2), heating at 85°C for 3 hours, and then filtering, washing and drying the reaction solution to obtain pretreated mullite whiskers;

[0057] (2) according to the mass ratio of magnesium nitrate, ferric nitrate, sodium hydroxide and water being 1:0.8:0.9:55, taking half of the total amount of water, adding magnesium nitrate and ferric nitrate thereto, to obtain a mixed solution of magnesium nitrate and ferric nitrate, then adding sodium hydroxide to the remaining water to obtain a sodium hydroxide solution, and under a nitrogen atmosphere, stirring and mixing the mixed solution and the sodium hydroxide solution to obtain a mixed solution;

[0058] (3) adding the mullite whiskers pretreated in step (1) to the mixed solution of step (2), wherein the mass ratio of the pretreated mullite whiskers to the magnesium nitrate in the mixed solution obtained in step (2) is 1:8; stirring for 30 minutes under a nitrogen atmosphere, adding the whiskers to a reactor, performing a hydrothermal reaction at 120° C. for 24 hours, centrifuging the reaction solution at 10,000 rpm for 10 minutes, and washing the precipitate with deionized water three times to obtain the product.

[0059] The rattan bark powder comprises the following preparation steps: taking the outer bark of healthy Celastrus orbiculatus, drying it, then grinding it in a high-energy ball mill, and spray drying it to obtain the rattan bark powder with a particle size of 100-200 nm.

[0060] This embodiment also provides a method for preparing a long-life asphalt mixture based on the addition of basalt fiber, comprising the following steps:

[0061] a. According to the above parts by weight, the basalt fiber, aggregate, filler, rattan bark powder was stirred and mixed to obtain a mixed material;

[0062] b. Add the above mixture into asphalt, heat at 170℃ and stir evenly.

[0063] Comparative Example 1

[0064] This comparative example provides a long-life asphalt mixture based on the addition of basalt fiber, which differs from Example 1 only in that: the preparation process of the filler is as follows: according to the mass ratio of magnesium nitrate, ferric nitrate, sodium hydroxide and water being 1:0.6:0.7:50, half of the above total water is added thereto with magnesium nitrate and ferric nitrate to obtain a mixed solution of magnesium nitrate and ferric nitrate, and then sodium hydroxide is added to the remaining water to obtain a sodium hydroxide solution. Under a nitrogen atmosphere, the mixed solution and the sodium hydroxide solution are stirred and mixed to obtain a mixed solution; the mixture is added to a reactor, hydrothermally reacted at 115°C for 28 hours, the reaction solution is centrifuged at 10,000 rpm for 10 minutes, and the precipitate is washed 3 times with deionized water to obtain the filler. The rest is the same as Example 1.

[0065] Comparative Example 2

[0066] This comparative example provides a long-life asphalt mixture based on the addition of basalt fiber. The only difference from Example 1 is that the preparation process of the filler is as follows: the pretreated mullite whiskers and the filler prepared in Comparative Example 1 are stirred and mixed evenly to obtain the mixture. The rest is the same as Example 1.

[0067] Comparative Example 3

[0068] This comparative example provides a long-life asphalt mixture based on the addition of basalt fiber. The difference from Example 1 is that the rattan bark powder is omitted, and the other aspects are the same as Example 1.

[0069] Test Example 1

[0070] (1) The water permeability coefficient, freeze-thaw splitting tensile strength ratio, and Marshall stability of the asphalt mixtures of Examples 1-3 and Comparative Examples 1-3 were tested according to the test method of JTG-E20-2011 "Test Procedures for Asphalt and Asphalt Mixtures in Highway Engineering".

[0071] (2) The wear of the asphalt mixtures of Examples 1-3 and Comparative Examples 1-3 was tested using a universal friction and wear tester, with a load of 50 N, a rotation speed of 180 r / min, and a test time of 2 h. The test results are shown in Table 1:

[0072] Table 1

[0073]

[0074] As shown in Table 1, the water permeability coefficient, freeze-thaw splitting strength ratio, stability, wear rate, and other properties of Examples 1-3 of the present invention are superior to those of Comparative Examples 1-3. The asphalt mixtures of Examples 1-3 have good wear resistance, water permeability, mechanical properties, and stability, and have better durability and service life.

[0075] Freeze-thaw splitting strength ratio is one of the important indicators for evaluating the water stability of asphalt mixture. It refers to the ratio of the strength of the asphalt mixture specimen to the splitting failure before and after being damaged by water after the asphalt mixture specimen is subjected to freeze-thaw cycles. Compared with Example 1, Comparative Example 1 omitted the addition of mullite whiskers, Comparative Example 2 changed the preparation method of the filler, and Comparative Example 3 omitted the addition of rattan bark powder. The water permeability coefficient, freeze-thaw splitting strength ratio, Marshall stability and wear resistance of the asphalt mixture all showed a significant decrease. The reason for the above results is that mullite whiskers have high strength, high toughness and high heat resistance, and after pretreatment, they give the filler a larger specific surface area. This filler with a large specific surface area can be more effectively combined with ingredients such as asphalt and aggregate in the asphalt mixture to form a more compact structure, thereby improving the overall performance of the mixture. The use of rattan bark powder and filler can improve the water absorption rate of the asphalt mixture and improve the water permeability of the asphalt mixture. It can drain water better when it comes into contact with water, reducing the occurrence of water damage. At the same time, its natural fiber structure can also enhance the toughness of the mixture and improve its crack resistance.

[0076] In addition, the present invention uses a hydrothermal method to prepare fillers from pretreated mullite whiskers, magnesium nitrate and zinc nitrate, and uses them in combination with rattan bark powder. This can also significantly improve the adhesion between asphalt and aggregate, forming a more solid bonding interface, allowing asphalt to better penetrate into the surface of the aggregate, forming a tight wrapping layer, thereby improving the overall strength and wear resistance of the mixture.

[0077] The above embodiments are only preferred embodiments of the present invention and cannot be used to limit the scope of protection of the present invention. Any non-substantial changes and replacements made by technicians in this field on the basis of the present invention fall within the scope of protection required by the present invention.

Claims

1. Long-life asphalt mixture based on the addition of basalt fiber, characterized in that, The invention comprises 50-60 parts of asphalt, 1-5 parts of basalt fiber, 450-500 parts of aggregate, 10-20 parts of filler and 1-3 parts of rattan bark powder.

2. The long-life asphalt mixture based on the addition of basalt fiber according to claim 1, characterized in that: The preparation process of the filler is as follows: (1) Pre-treating mullite whiskers; (2) adding a mixed solution of magnesium nitrate and ferric nitrate to a sodium hydroxide solution, stirring and mixing to obtain a mixed solution; (3) adding the mullite whiskers pretreated in step (1) into the mixed solution of step (2), stirring and mixing them evenly, and then performing a hydrothermal reaction to obtain the product.

3. The long-life asphalt mixture based on the addition of basalt fiber according to claim 2, characterized in that: The pretreatment process of step (1) is as follows: adding mullite whiskers into a mixed solvent and heating the mixture, and then filtering, washing and drying the reaction solution to obtain the product.

4. The long-life asphalt mixture based on the addition of basalt fiber according to claim 3, characterized in that: The mixed solvent is prepared from anhydrous ethanol and acetone in a volume ratio of 1:(1-2), and the heating temperature is 75-85° C. and the heating time is 3-5 hours.

5. The long-life asphalt mixture based on the addition of basalt fiber according to claim 2, characterized in that: In step (2), the mass ratio of the magnesium nitrate, ferric nitrate, sodium hydroxide and water is 1:(0.4-0.8):(0.5-0.9):(45-55).

6. The long-life asphalt mixture based on the addition of basalt fiber according to claim 2, characterized in that: In step (3), the mass ratio of the pretreated mullite whiskers to the magnesium nitrate in the mixed solution obtained in step (2) is 1:(3-8).

7. The long-life asphalt mixture based on the addition of basalt fiber according to claim 2, characterized in that: In step (3), the temperature of the hydrothermal reaction is 110-120° C., and the time is 24-30 h.

8. The long-life asphalt mixture based on the addition of basalt fiber according to claim 2, characterized in that: The diameter of the mullite whisker is 0.2-3 μm, and the length is 5-200 μm; the particle size of the aggregate is 0.5-2.5 mm.

9. The method for preparing a long-life asphalt mixture based on adding basalt fiber according to any one of claims 1 to 8, characterized in that: The steps include: a. According to the above parts by weight, the basalt fiber, aggregate, filler, rattan bark powder was stirred and mixed to obtain a mixed material; b. Add the above mixture into asphalt, heat at 160-170℃ and stir evenly.

10. Use of the long-life asphalt mixture based on the addition of basalt fiber according to any one of claims 1 to 8 in the field of road engineering construction.

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