A modified aeolian sand road base material and its preparation method

Abstract

This invention discloses a modified aeolian sand road base material, composed of the following parts by weight: aeolian sand: 620-635 parts; fine aggregate: 1030-1055 parts; coarse aggregate: 3510-3580 parts; modified aeolian sand powder: 230-265 parts; cement: 50-80 parts; superabsorbent polymer: 0.32-0.96 parts; water: 425-525 parts. The modified aeolian sand is a composite modified aeolian sand of metakaolin, phosphogypsum, and triethanolamine, and is cured using a water glass-polyvinyl acetate composite curing agent. The modified aeolian sand has characteristics such as small particle size, high specific surface area, strong reactivity, and good viscosity. Adding it to base materials can improve their mechanical properties, volume stability, and durability, and it has low cost and good economic benefits, showing good application potential in cementitious materials and pavement materials.

Description

Technical Field

[0001] This invention relates to the field of road engineering materials technology, and in particular to a modified aeolian sand road base material. Background Technology

[0002] The characteristics of highway construction in desert areas include an extreme scarcity of high-quality materials, inconvenient access, and long transportation distances, significantly increasing construction costs. Reducing energy consumption and utilizing locally sourced materials are two crucial objectives in desert highway construction. The rational development of natural resources includes using aeolian sand instead of stone chips as fine aggregate in road base course preparation, effectively alleviating the imbalance between supply and demand for fine aggregates, and providing a reference for the sustainable development of road construction materials. Therefore, using aeolian sand to replace conventional fine aggregates in road base course preparation is an inevitable trend in engineering materials development, and will undoubtedly bring significant economic and social benefits.

[0003] Current research mainly focuses on the macroscopic physical properties of aeolian sand and its engineering applications as fine aggregate in road and building construction. While this research has revealed the origins, composition, and engineering value of aeolian sand to some extent, it remains lacking in understanding the intrinsic properties of aeolian sand containing silicon oxides and its potential cementitious characteristics. Therefore, it is necessary to conduct systematic research and development on the cementitious properties of aeolian sand. The amount of aeolian sand in road base mixtures is relatively small, not reaching a sufficiently high content to support the resource utilization and large-scale application of aeolian sand. This has resulted in the failure to fully explore the potential economic and social benefits of aeolian sand, leading to serious resource waste. There is also limited research on the strength characteristics, mechanical properties, and road performance of cement-stabilized graded crushed stone mixtures containing aeolian sand. Furthermore, given the extremely dry conditions in desert regions, the roadbed materials need to have high strength to ensure load-bearing capacity, low shrinkage to prevent pavement cracking, and meet mechanical performance requirements. Current technologies cannot meet these demands, requiring further research and development. Summary of the Invention

[0004] The technical problem to be solved: The technical problem to be solved by the present invention is to provide a modified aeolian sand road base material.

[0005] Technical solution: A modified aeolian sand road base material, composed of the following parts by weight:

[0006] Aeolian sand: 620-635 parts;

[0007] Fine aggregate: 1030–1055 parts;

[0008] Coarse aggregate: 3510-3580 parts;

[0009] Modified aeolian sand powder: 230-265 parts;

[0010] Cement: 50-80 parts;

[0011] Superabsorbent polymer: 0.32–0.96 parts;

[0012] Water: 425-525 parts.

[0013] Preferably, the preparation method of the modified aeolian sand powder includes the following steps:

[0014] S1. Heat and dry the aeolian sand, calcine it at 750-850℃ and keep it at that temperature, then rapidly heat it to 1000-1100℃ and keep it at that temperature, and finally cool it to obtain calcined aeolian sand.

[0015] S2. Calcined aeolian sand, metakaolin, and phosphogypsum powder are mixed and placed in a ball mill, and triethanolamine is added for grinding to obtain composite powder;

[0016] S3. Add sodium silicate and polyvinyl acetate to deionized water, add emulsifier and stir ultrasonically to obtain water glass-polyvinyl acetate emulsion;

[0017] S4. Spray the water glass-polyvinyl acetate emulsion evenly onto the composite powder until it solidifies to obtain modified aeolian sand powder.

[0018] Preferably, the ratio of aeolian sand, metakaolin, phosphogypsum powder and triethanolamine in step S2 is 75:22.5-23.5:1.5-2.5:0.02-0.04; and the ratio of polyvinyl acetate and sodium silicate in step S3 is 1:2-2.5.

[0019] Preferably, the metakaolin has a specific surface area of ​​672–678 m². 2 / kg, with SiO2, Al2O3, Fe2O3, CaO, and MgO contents of 52-53%, 41-42%, 3.0-3.5%, 0.25-0.35%, and 0.15-0.25%, respectively, and an activity coefficient of 0.21-0.38; preferably, the modified aeolian sand powder has a specific surface area of ​​300-350 m². 2 / kg, with a particle size distribution of 1–100 μm.

[0020] Preferably, the aeolian sand has a particle size range of 0.075–0.3 mm, a uniformity coefficient of 2.1–2.15, a curvature coefficient of 2.1–2.15, a fineness modulus of 0.25–0.3, and an apparent density of 2.6–2.7 g / cm³. 3 The mud content is 9.0%–9.2%, and the water absorption rate is 0.47%–0.72%.

[0021] Preferably, the fine aggregate has a particle size range of 2.36–4.75 mm and an apparent density of 2.6–2.7 g / cm³.3 Crushing value 19-19.5%, needle-like and flaky content 14-14.5%, water absorption rate 0.75-0.8%.

[0022] Preferably, the coarse aggregate has a particle size range of 4.75–9.5 mm and 9.5–26.5 mm; wherein the apparent density of the 4.75–9.5 mm crushed stone is 2.7–2.8 g / cm³. 3 Crushing value 17.5–18%, needle-like and flaky content 13–14%, water absorption 0.75–0.8%; apparent density of 9.5–26.5 mm crushed stone 2.6–2.7 g / cm³. 3 Crushing value 19.5-20.5%, needle-like and flaky content 11.5-12.5%, water absorption rate 0.2-0.25%.

[0023] Preferably, the cement is P·O 42.5 ordinary Portland cement with a specific surface area of ​​3.6–3.7 m². 2 / kg, initial and final setting times are 200-210 min and 250-260 min respectively, 3d and 28d compressive and flexural strengths are 30-31 MPa and 50-51 MPa respectively, and ignition vector is 3.8-4.0%; the required mixing water is tap water.

[0024] Preferably, the superabsorbent resin includes any one or more of ionic superabsorbent resin, nonionic superabsorbent resin, and composite superabsorbent resin; the additional water absorption capacity of the superabsorbent resin (superabsorbent resin dosage × water absorption ratio) is 10 to 30 times, and the particle size range is 80 to 100 mesh.

[0025] Preferably, the preparation method of the modified aeolian sand road base material includes the following steps:

[0026] S11. Mix aeolian sand with a particle size of 0.01-2.36 mm, fine aggregate of 2.36-4.75 mm, coarse aggregate of 4.75-26.5 mm in a certain proportion, stir evenly, cover with plastic wrap and let it sit for 5-7 hours to fully impregnate the surface to obtain impregnated mixture;

[0027] S12. Mix the superabsorbent resin, cement and modified aeolian sand powder in a certain proportion until uniform, and obtain the mixture;

[0028] S13. Mix and stir the mixtures obtained in S11 and S12 until homogeneous, then cure under static pressure to obtain modified aeolian sand road base material. Beneficial effects: Compared with the prior art, this invention has the following characteristics:

[0029] The modified aeolian sand powder in the modified aeolian sand road base material of the present invention is obtained by high-temperature calcination and mechanical grinding. It has the characteristics of large specific surface area and strong reactivity, which can improve the mechanical properties and shrinkage resistance of the base mixture.

[0030] Aeolian sand has a loose structure, lacks interparticle cohesion, and has poor water retention, resulting in poor engineering properties. Therefore, it is unsuitable as a direct filler for aeolian sand embankment subgrade. Modification is necessary: ​​high-temperature calcined aeolian sand is ground, and metakaolin, phosphogypsum, and triethanolamine are added. Untreated aeolian sand has a high degree of crystallinity and low activity. High-temperature calcination and other heat treatments remove free water from the particles, transforming the stable silica-alumina structure into a metastable structure, thus increasing the reactivity of silica and alumina in the aeolian sand. Grinding reduces the particle size, increases density and specific surface area, and disrupts some of the SiO2 crystal structure on the particle surface, altering the bond energy between crystals, creating vacancies and defects, and facilitating chemical bond breaking. This lowers the activation energy, making it easier to undergo secondary hydration reactions with cement hydration products, thereby improving its pozzolanic activity. Metakaolin is a typical aluminum-rich pozzolanic material with high pozzolanic activity; its main components are Al2O3 and SiO2. Phosphogypsum's main components are calcium sulfate dihydrate and Ca... 2+ With SO4 2- The combined action of these substances can react with the active Al2O3 in aeolian sand and metakaolin to produce ettringite (3CaO·Al2O3·3CaSO4·32H2O). Phosphogypsum, together with triethanolamine, acts as a composite activator, activating the latent activity in aeolian sand; SO4 2- It can also replace SiO4 2- SiO4 2- With Ca 2+ The reaction generates CSH gel, improving the mechanical properties and durability of cement-based materials. Furthermore, aeolian sand exhibits significant shrinkage under the action of the activator, while the SO3 in phosphogypsum acts as an expansion source, inhibiting shrinkage. In addition, triethanolamine chemically reacts with the surface of aeolian sand particles, forming a dense protective film that prevents particle adhesion, thereby reducing inter-particle friction, improving grinding efficiency, and acting as a dispersant to ensure uniform particle dispersion and reduce agglomeration. Chemical curing of the ground modified aeolian sand using organic-inorganic composite curing materials allows for complementary advantages between organic and inorganic materials, achieving better curing results and ultimately improving the material's mechanical properties, stability, and durability.

[0031] In base course materials, modified aeolian sand powder can replace part of the cementitious materials, reducing energy consumption and carbon emissions during cement production, thus being environmentally friendly. Adding unmodified aeolian sand particles to adjust the proportion of natural sand improves the particle size distribution of fine aggregates, resulting in better compaction of the aeolian sand-graded crushed stone base course. This reduces the production cost of base course materials and plays a positive role in the sustainable development of mineral resources and desertification control. Due to its excellent water absorption, retention, and release properties, superabsorbent polymer (SAP) can introduce moisture into the aeolian sand base course mixture, compensate for humidity, promote the hydration degree of modified aeolian sand, and regulate the internal pore system of the mixture. This enhances the shrinkage crack resistance of the aeolian sand base course mixture, ensuring safe vehicle operation and extending the service life of highways.

[0032] Compared with the prior art, the present invention has the following advantages and positive effects:

[0033] This invention modifies aeolian sand using metakaolin, phosphogypsum, and triethanolamine, resulting in small particle size, large specific surface area, strong reactivity, and good viscosity, making it an excellent cementitious material.

[0034] This invention uses sodium silicate-polyvinyl acetate composite curing agent to cure modified aeolian sand. The complementary advantages of organic and inorganic materials increase the water retention and adhesion of the aeolian sand.

[0035] The present invention incorporates superabsorbent resin, which can absorb and retain water, thereby improving the volume stability of the material. Attached Figure Description

[0036] Figure 1 This is a particle size distribution diagram of modified aeolian sand. Detailed Implementation

[0037] To further understand the present invention, preferred embodiments of the present invention will be described below in conjunction with examples.

[0038] Specific examples of preferred choices are as follows:

[0039] Example 1:

[0040] A modified aeolian sand road base material, composed of the following parts by weight:

[0041] Aeolian sand: 620.3 samples;

[0042] Fine aggregate: 1033.7 parts;

[0043] Coarse aggregate: 3515.1 parts;

[0044] Modified aeolian sand powder: 232.6 parts;

[0045] Cement: 77.6 parts;

[0046] Superabsorbent polymer: 0.32 parts;

[0047] Water: 520.5 parts;

[0048] The superabsorbent resin is a composite superabsorbent resin with an additional water absorption capacity of 3.2 parts;

[0049] The preparation method of the modified aeolian sand powder includes the following steps:

[0050] S1. Heat and dry the aeolian sand, calcine it at 800℃ and keep it at that temperature, then rapidly heat it to 1050℃ and keep it at that temperature, and finally cool it to obtain calcined aeolian sand.

[0051] S2. Calcined aeolian sand, metakaolin, and phosphogypsum powder are mixed and placed in a ball mill, and triethanolamine is added for grinding. The ratio of aeolian sand, metakaolin, phosphogypsum powder and triethanolamine is 75:23:2:0.03 to obtain composite powder.

[0052] S3. Sodium silicate and polyvinyl acetate are added to deionized water in a ratio of 1:2.2, and an emulsifier is added and ultrasonically stirred to obtain a water glass-polyvinyl acetate emulsion.

[0053] S4. Spray the water glass-polyvinyl acetate emulsion evenly onto the composite powder until it solidifies to obtain modified aeolian sand powder.

[0054] The preparation method of the modified aeolian sand road base material includes the following steps:

[0055] S11. Mix aeolian sand with a particle size of 0.01-2.36 mm, fine aggregate of 2.36-4.75 mm, and coarse aggregate of 4.75-26.5 mm in a certain proportion. Cover the mixture with plastic wrap and let it sit for 6 hours to fully impregnate the surface, thus obtaining an impregnated mixture.

[0056] S12. Mix the superabsorbent resin, cement and modified aeolian sand powder in a certain proportion until uniform, and obtain the mixture;

[0057] S13. Mix and stir the mixtures obtained from S11 and S12 until uniform, then cure under static pressure to obtain modified aeolian sand road base material.

[0058] Example 2:

[0059] A modified aeolian sand road base material, composed of the following parts by weight:

[0060] Aeolian sand: 626 samples;

[0061] Fine aggregate: 1043.4 parts;

[0062] Coarse aggregate: 3547.6 parts;

[0063] Modified aeolian sand powder: 234.8 parts;

[0064] Cement: 78.3 parts;

[0065] Superabsorbent polymer: 0.64 parts;

[0066] Water: 470 portions;

[0067] The superabsorbent resin is a composite superabsorbent resin with an additional water absorption capacity of 12.8 parts;

[0068] The preparation method of the modified aeolian sand powder includes the following steps:

[0069] S1. Heat and dry the aeolian sand, calcine it at 800℃ and keep it at that temperature, then rapidly heat it to 1050℃ and keep it at that temperature, and finally cool it to obtain calcined aeolian sand.

[0070] S2. Calcined aeolian sand, metakaolin, and phosphogypsum powder are mixed and placed in a ball mill, and triethanolamine is added for grinding. The ratio of aeolian sand, metakaolin, phosphogypsum powder and triethanolamine is 75:23:2:0.03 to obtain composite powder.

[0071] S3. Sodium silicate and polyvinyl acetate are added to deionized water in a ratio of 1:2.2, and an emulsifier is added and ultrasonically stirred to obtain a water glass-polyvinyl acetate emulsion.

[0072] S4. Spray the water glass-polyvinyl acetate emulsion evenly onto the composite powder until it solidifies to obtain modified aeolian sand powder.

[0073] The preparation method of the modified aeolian sand road base material includes the following steps:

[0074] S11. Mix aeolian sand with a particle size of 0.01-2.36 mm, fine aggregate of 2.36-4.75 mm, and coarse aggregate of 4.75-26.5 mm in a certain proportion. Cover the mixture with plastic wrap and let it sit for 6 hours to fully impregnate the surface, thus obtaining an impregnated mixture.

[0075] S12. Mix the superabsorbent resin, cement and modified aeolian sand powder in a certain proportion until uniform, and obtain the mixture;

[0076] S13. Mix and stir the mixtures obtained from S11 and S12 until uniform, then cure under static pressure to obtain modified aeolian sand road base material.

[0077] Example 3:

[0078] A modified aeolian sand road base material, composed of the following parts by weight:

[0079] Aeolian sand: 630.7 samples;

[0080] Fine aggregate: 1051.1 parts;

[0081] Coarse aggregate: 3573.9 parts;

[0082] Modified aeolian sand powder: 236.5 parts;

[0083] Cement: 78.8 parts;

[0084] Superabsorbent polymer: 0.96 parts;

[0085] Water: 429 portions;

[0086] The superabsorbent resin is a composite superabsorbent resin with an additional water absorption capacity of 28.8 parts;

[0087] The preparation method of the modified aeolian sand powder includes the following steps:

[0088] S1. Heat and dry the aeolian sand, calcine it at 800℃ and keep it at that temperature, then rapidly heat it to 1050℃ and keep it at that temperature, and finally cool it to obtain calcined aeolian sand.

[0089] S2. Calcined aeolian sand, metakaolin, and phosphogypsum powder are mixed and placed in a ball mill, and triethanolamine is added for grinding. The ratio of aeolian sand, metakaolin, phosphogypsum powder and triethanolamine is 75:23:2:0.03 to obtain composite powder.

[0090] S3. Sodium silicate and polyvinyl acetate are added to deionized water in a ratio of 1:2.2, and an emulsifier is added and ultrasonically stirred to obtain a water glass-polyvinyl acetate emulsion.

[0091] S4. Spray the water glass-polyvinyl acetate emulsion evenly onto the composite powder until it solidifies to obtain modified aeolian sand powder.

[0092] The preparation method of the modified aeolian sand road base material includes the following steps:

[0093] S11. Mix aeolian sand with a particle size of 0.01-2.36 mm, fine aggregate of 2.36-4.75 mm, and coarse aggregate of 4.75-26.5 mm in a certain proportion. Cover the mixture with plastic wrap and let it sit for 6 hours to fully impregnate the surface, thus obtaining an impregnated mixture.

[0094] S12. Mix the superabsorbent resin, cement and modified aeolian sand powder in a certain proportion until uniform, and obtain the mixture;

[0095] S13. Mix and stir the mixtures obtained from S11 and S12 until uniform, then cure under static pressure to obtain modified aeolian sand road base material.

[0096] Example 4:

[0097] A modified aeolian sand road base material, composed of the following parts by weight:

[0098] Aeolian sand: 622.6 samples;

[0099] Fine aggregate: 1037.6 parts;

[0100] Coarse aggregate: 3528 parts;

[0101] Modified aeolian sand powder: 249 parts;

[0102] Cement: 62.3 parts;

[0103] Superabsorbent polymer: 0.62 parts;

[0104] Water: 429 portions;

[0105] The superabsorbent resin is a composite superabsorbent resin with an additional water absorption capacity of 18.6 parts;

[0106] The preparation method of the modified aeolian sand powder includes the following steps:

[0107] S1. Heat and dry the aeolian sand, calcine it at 800℃ and keep it at that temperature, then rapidly heat it to 1050℃ and keep it at that temperature, and finally cool it to obtain calcined aeolian sand.

[0108] S2. Calcined aeolian sand, metakaolin, and phosphogypsum powder are mixed and placed in a ball mill, and triethanolamine is added for grinding. The ratio of aeolian sand, metakaolin, phosphogypsum powder and triethanolamine is 75:23:2:0.03 to obtain composite powder.

[0109] S3. Sodium silicate and polyvinyl acetate are added to deionized water in a ratio of 1:2.2, and an emulsifier is added and ultrasonically stirred to obtain a water glass-polyvinyl acetate emulsion.

[0110] S4. Spray the water glass-polyvinyl acetate emulsion evenly onto the composite powder until it solidifies to obtain modified aeolian sand powder.

[0111] The preparation method of the modified aeolian sand road base material includes the following steps:

[0112] S11. Mix aeolian sand with a particle size of 0.01-2.36 mm, fine aggregate of 2.36-4.75 mm, and coarse aggregate of 4.75-26.5 mm in a certain proportion. Cover the mixture with plastic wrap and let it sit for 6 hours to fully impregnate the surface, thus obtaining an impregnated mixture.

[0113] S12. Mix the superabsorbent resin, cement and modified aeolian sand powder in a certain proportion until uniform, and obtain the mixture;

[0114] S13. Mix and stir the mixtures obtained from S11 and S12 until uniform, then cure under static pressure to obtain modified aeolian sand road base material.

[0115] Example 5:

[0116] A modified aeolian sand road base material, composed of the following parts by weight:

[0117] Aeolian sand: 627.2 samples;

[0118] Fine aggregate: 1045.3 parts;

[0119] Coarse aggregate: 3554 parts;

[0120] Modified aeolian sand powder: 251 parts;

[0121] Cement: 62.7 parts;

[0122] Superabsorbent polymer: 0.96 parts;

[0123] Water: 459.8 portions;

[0124] The superabsorbent resin is a composite superabsorbent resin with an additional water absorption capacity of 9.5 parts;

[0125] The preparation method of the modified aeolian sand powder includes the following steps:

[0126] S1. Heat and dry the aeolian sand, calcine it at 800℃ and keep it at that temperature, then rapidly heat it to 1050℃ and keep it at that temperature, and finally cool it to obtain calcined aeolian sand.

[0127] S2. Calcined aeolian sand, metakaolin, and phosphogypsum powder are mixed and placed in a ball mill, and triethanolamine is added for grinding. The ratio of aeolian sand, metakaolin, phosphogypsum powder and triethanolamine is 75:23:2:0.03 to obtain composite powder.

[0128] S3. Sodium silicate and polyvinyl acetate are added to deionized water in a ratio of 1:2.2, and an emulsifier is added and ultrasonically stirred to obtain a water glass-polyvinyl acetate emulsion.

[0129] S4. Spray the water glass-polyvinyl acetate emulsion evenly onto the composite powder until it solidifies to obtain modified aeolian sand powder.

[0130] The preparation method of the modified aeolian sand road base material includes the following steps:

[0131] S11. Mix aeolian sand with a particle size of 0.01-2.36 mm, fine aggregate of 2.36-4.75 mm, and coarse aggregate of 4.75-26.5 mm in a certain proportion. Cover the mixture with plastic wrap and let it sit for 6 hours to fully impregnate the surface, thus obtaining an impregnated mixture.

[0132] S12. Mix the superabsorbent resin, cement and modified aeolian sand powder in a certain proportion until uniform, and obtain the mixture;

[0133] S13. Mix and stir the mixtures obtained from S11 and S12 until uniform, then cure under static pressure to obtain modified aeolian sand road base material.

[0134] Example 6:

[0135] A modified aeolian sand road base material, composed of the following parts by weight:

[0136] Aeolian sand: 624.9 samples;

[0137] Fine aggregate: 1041.5 parts;

[0138] Coarse aggregate: 3541.1 parts;

[0139] Modified aeolian sand powder: 250 parts;

[0140] Cement: 62.5 parts;

[0141] Superabsorbent polymer: 0.32 parts;

[0142] Water: 480 portions;

[0143] The superabsorbent resin is a composite superabsorbent resin with an additional water absorption capacity of 6.4 parts;

[0144] The preparation method of the modified aeolian sand powder includes the following steps:

[0145] S1. Heat and dry the aeolian sand, calcine it at 800℃ and keep it at that temperature, then rapidly heat it to 1050℃ and keep it at that temperature, and finally cool it to obtain calcined aeolian sand.

[0146] S2. Calcined aeolian sand, metakaolin, and phosphogypsum powder are mixed and placed in a ball mill, and triethanolamine is added for grinding. The ratio of aeolian sand, metakaolin, phosphogypsum powder and triethanolamine is 75:23:2:0.03 to obtain composite powder.

[0147] S3. Sodium silicate and polyvinyl acetate are added to deionized water in a ratio of 1:2.2, and an emulsifier is added and ultrasonically stirred to obtain a water glass-polyvinyl acetate emulsion.

[0148] S4. Spray the water glass-polyvinyl acetate emulsion evenly onto the composite powder until it solidifies to obtain modified aeolian sand powder.

[0149] The preparation method of the modified aeolian sand road base material includes the following steps:

[0150] S11. Mix aeolian sand with a particle size of 0.01-2.36 mm, fine aggregate of 2.36-4.75 mm, and coarse aggregate of 4.75-26.5 mm in a certain proportion. Cover the mixture with plastic wrap and let it sit for 6 hours to fully impregnate the surface, thus obtaining an impregnated mixture.

[0151] S12. Mix the superabsorbent resin, cement and modified aeolian sand powder in a certain proportion until uniform, and obtain the mixture;

[0152] S13. Mix and stir the mixtures obtained from S11 and S12 until uniform, then cure under static pressure to obtain modified aeolian sand road base material.

[0153] Example 7:

[0154] A modified aeolian sand road base material, composed of the following parts by weight:

[0155] Aeolian sand: 620.3 samples;

[0156] Fine aggregate: 1033.9 parts;

[0157] Coarse aggregate: 3515.1 parts;

[0158] Modified aeolian sand powder: 258.5 parts;

[0159] Cement: 51.7 parts;

[0160] Superabsorbent polymer: 0.96 parts;

[0161] Water: 520.5 parts;

[0162] The superabsorbent resin is a composite superabsorbent resin with an additional water absorption capacity of 19.2 parts;

[0163] The preparation method of the modified aeolian sand powder includes the following steps:

[0164] S1. Heat and dry the aeolian sand, calcine it at 800℃ and keep it at that temperature, then rapidly heat it to 1050℃ and keep it at that temperature, and finally cool it to obtain calcined aeolian sand.

[0165] S2. Calcined aeolian sand, metakaolin, and phosphogypsum powder are mixed and placed in a ball mill, and triethanolamine is added for grinding. The ratio of aeolian sand, metakaolin, phosphogypsum powder and triethanolamine is 75:23:2:0.03 to obtain composite powder.

[0166] S3. Sodium silicate and polyvinyl acetate are added to deionized water in a ratio of 1:2.2, and an emulsifier is added and ultrasonically stirred to obtain a water glass-polyvinyl acetate emulsion.

[0167] S4. Spray the water glass-polyvinyl acetate emulsion evenly onto the composite powder until it solidifies to obtain modified aeolian sand powder.

[0168] The preparation method of the modified aeolian sand road base material includes the following steps:

[0169] S11. Mix aeolian sand with a particle size of 0.01-2.36 mm, fine aggregate of 2.36-4.75 mm, and coarse aggregate of 4.75-26.5 mm in a certain proportion. Cover the mixture with plastic wrap and let it sit for 6 hours to fully impregnate the surface, thus obtaining an impregnated mixture.

[0170] S12. Mix the superabsorbent resin, cement and modified aeolian sand powder in a certain proportion until uniform, and obtain the mixture;

[0171] S13. Mix and stir the mixtures obtained from S11 and S12 until uniform, then cure under static pressure to obtain modified aeolian sand road base material.

[0172] Example 8:

[0173] A modified aeolian sand road base material, composed of the following parts by weight:

[0174] Aeolian sand: 622 samples;

[0175] Fine aggregate: 1036.7 parts;

[0176] Coarse aggregate: 3524.8 parts;

[0177] Modified aeolian sand powder: 259.2 parts;

[0178] Cement: 51.8 parts;

[0179] Superabsorbent polymer: 0.32 parts;

[0180] Water: 505.5 parts;

[0181] The superabsorbent resin is a composite superabsorbent resin with an additional water absorption capacity of 9.6 parts;

[0182] The preparation method of the modified aeolian sand powder includes the following steps:

[0183] S1. Heat and dry the aeolian sand, calcine it at 800℃ and keep it at that temperature, then rapidly heat it to 1050℃ and keep it at that temperature, and finally cool it to obtain calcined aeolian sand.

[0184] S2. Calcined aeolian sand, metakaolin, and phosphogypsum powder are mixed and placed in a ball mill, and triethanolamine is added for grinding. The ratio of aeolian sand, metakaolin, phosphogypsum powder and triethanolamine is 75:23:2:0.03 to obtain composite powder.

[0185] S3. Sodium silicate and polyvinyl acetate are added to deionized water in a ratio of 1:2.2, and an emulsifier is added and ultrasonically stirred to obtain a water glass-polyvinyl acetate emulsion.

[0186] S4. Spray the water glass-polyvinyl acetate emulsion evenly onto the composite powder until it solidifies to obtain modified aeolian sand powder.

[0187] The preparation method of the modified aeolian sand road base material includes the following steps:

[0188] S11. Mix aeolian sand with a particle size of 0.01-2.36 mm, fine aggregate of 2.36-4.75 mm, and coarse aggregate of 4.75-26.5 mm in a certain proportion. Cover the mixture with plastic wrap and let it sit for 6 hours to fully impregnate the surface, thus obtaining an impregnated mixture.

[0189] S12. Mix the superabsorbent resin, cement and modified aeolian sand powder in a certain proportion until uniform, and obtain the mixture;

[0190] S13. Mix and stir the mixtures obtained from S11 and S12 until uniform, then cure under static pressure to obtain modified aeolian sand road base material.

[0191] Example 9:

[0192] A modified aeolian sand road base material, composed of the following parts by weight:

[0193] Aeolian sand: 628.3 samples;

[0194] Fine aggregate: 1047.2 parts;

[0195] Coarse aggregate: 3560.6 parts;

[0196] Modified aeolian sand powder: 261.8 parts;

[0197] Cement: 52.4 parts;

[0198] Superabsorbent polymer: 0.64 parts;

[0199] Water: 449.6 portions;

[0200] The superabsorbent resin is a composite superabsorbent resin with an additional water absorption capacity of 6.4 parts;

[0201] The preparation method of the modified aeolian sand powder includes the following steps:

[0202] S1. Heat and dry the aeolian sand, calcine it at 800℃ and keep it at that temperature, then rapidly heat it to 1050℃ and keep it at that temperature, and finally cool it to obtain calcined aeolian sand.

[0203] S2. Calcined aeolian sand, metakaolin, and phosphogypsum powder are mixed and placed in a ball mill, and triethanolamine is added for grinding. The ratio of aeolian sand, metakaolin, phosphogypsum powder and triethanolamine is 75:23:2:0.03 to obtain composite powder.

[0204] S3. Sodium silicate and polyvinyl acetate are added to deionized water in a ratio of 1:2.2, and an emulsifier is added and ultrasonically stirred to obtain a water glass-polyvinyl acetate emulsion.

[0205] S4. Spray the water glass-polyvinyl acetate emulsion evenly onto the composite powder until it solidifies to obtain modified aeolian sand powder.

[0206] The preparation method of the modified aeolian sand road base material includes the following steps:

[0207] S11. Mix aeolian sand with a particle size of 0.01-2.36 mm, fine aggregate of 2.36-4.75 mm, and coarse aggregate of 4.75-26.5 mm in a certain proportion. Cover the mixture with plastic wrap and let it sit for 6 hours to fully impregnate the surface, thus obtaining an impregnated mixture.

[0208] S12. Mix the superabsorbent resin, cement and modified aeolian sand powder in a certain proportion until uniform, and obtain the mixture;

[0209] S13. The mixtures obtained in S11 and S12 are mixed and stirred evenly, then cured after static pressing to obtain modified aeolian sand road base material. To further illustrate the technical effects of this invention, a comparative example is also provided, as follows:

[0210] Comparative Example 1:

[0211] A base material, comprising the following parts by weight:

[0212] Aeolian sand: 625.3 samples;

[0213] Fine aggregate: 1050.8 parts;

[0214] Coarse aggregate: 3566 parts;

[0215] Metakaolin: 216.6 parts;

[0216] Cement: 72.2 parts;

[0217] Water: 452.3 parts;

[0218] The preparation method of the base material includes the following steps:

[0219] S11. Mix aeolian sand with a particle size of 0.01-2.36 mm, fine aggregate of 2.36-4.75 mm, and coarse aggregate of 4.75-26.5 mm in a certain proportion. Cover the mixture with plastic wrap and let it sit for 6 hours to fully impregnate the surface, thus obtaining an impregnated mixture.

[0220] S12. Mix cement and metakaolin in a certain proportion until homogeneous to obtain a mixture;

[0221] S13. Mix and stir the mixtures obtained from S11 and S12 until uniform, then cure under static pressure to obtain the base material.

[0222] Comparative Example 2:

[0223] A base material, comprising the following parts by weight:

[0224] Aeolian sand: 630.2 samples;

[0225] Fine aggregate: 1044.9 parts;

[0226] Coarse aggregate: 3534 parts;

[0227] Metakaolin: 244.4 parts;

[0228] Cement: 61.1 parts;

[0229] Water: 478.2 portions;

[0230] The preparation method of the base material includes the following steps:

[0231] S11. Mix aeolian sand with a particle size of 0.01-2.36 mm, fine aggregate of 2.36-4.75 mm, and coarse aggregate of 4.75-26.5 mm in a certain proportion. Cover the mixture with plastic wrap and let it sit for 6 hours to fully impregnate the surface, thus obtaining an impregnated mixture.

[0232] S12. Mix cement and metakaolin in a certain proportion until homogeneous to obtain a mixture;

[0233] S13. Mix and stir the mixtures obtained from S11 and S12 until uniform, then cure under static pressure to obtain the base material.

[0234] Comparative Example 3:

[0235] A base material, comprising the following parts by weight:

[0236] Aeolian sand: 621.7 samples;

[0237] Fine aggregate: 1044.5 parts;

[0238] Coarse aggregate: 3524 parts;

[0239] Metakaolin: 256 parts;

[0240] Cement: 51.2 parts;

[0241] Water: 433.5 portions;

[0242] The preparation method of the base material includes the following steps:

[0243] S11. Mix aeolian sand with a particle size of 0.01-2.36 mm, fine aggregate of 2.36-4.75 mm, and coarse aggregate of 4.75-26.5 mm in a certain proportion. Cover the mixture with plastic wrap and let it sit for 6 hours to fully impregnate the surface, thus obtaining an impregnated mixture.

[0244] S12. Mix cement and metakaolin in a certain proportion until homogeneous to obtain a mixture;

[0245] S13. Mix and stir the mixtures obtained from S11 and S12 until uniform, then cure under static pressure to obtain the base material.

[0246] Comparative Example 4:

[0247] A base material, comprising the following parts by weight:

[0248] Aeolian sand: 632.8 samples;

[0249] Fine aggregate: 1043.1 parts;

[0250] Coarse aggregate: 3535 parts;

[0251] Modified aeolian sand powder: 226.8 parts;

[0252] Cement: 75.6 parts;

[0253] Superabsorbent polymer: 0.64 parts;

[0254] Water: 447 portions;

[0255] The superabsorbent resin is a composite superabsorbent resin with an additional water absorption capacity of 12.8 parts;

[0256] The preparation method of the modified aeolian sand powder includes the following steps:

[0257] S1. Heat and dry the aeolian sand, calcine it at 800℃ and keep it at that temperature, then rapidly heat it to 1050℃ and keep it at that temperature, and finally cool it to obtain calcined aeolian sand.

[0258] S2. Calcined aeolian sand, metakaolin, and phosphogypsum powder are mixed and placed in a ball mill, and triethanolamine is added for grinding. The ratio of aeolian sand, metakaolin, phosphogypsum powder and triethanolamine is 75:23:2:0.03 to obtain modified aeolian sand powder.

[0259] The preparation method of the base material includes the following steps:

[0260] S11. Mix aeolian sand with a particle size of 0.01-2.36 mm, fine aggregate of 2.36-4.75 mm, and coarse aggregate of 4.75-26.5 mm in a certain proportion. Cover the mixture with plastic wrap and let it sit for 6 hours to fully impregnate the surface, thus obtaining an impregnated mixture.

[0261] S12. Mix the superabsorbent resin, cement and modified aeolian sand powder in a certain proportion until uniform, and obtain the mixture;

[0262] S13. Mix and stir the mixtures obtained from S11 and S12 until uniform, then cure under static pressure to obtain the base material.

[0263] Comparative Example 5:

[0264] A base material, comprising the following parts by weight:

[0265] Aeolian sand: 625.5 parts;

[0266] Fine aggregate: 1037.5 parts;

[0267] Coarse aggregate: 3562 parts;

[0268] Modified aeolian sand powder: 229.8 parts;

[0269] Cement: 76.6 parts;

[0270] Superabsorbent polymer: 0.64 parts;

[0271] Water: 439 portions;

[0272] The superabsorbent resin is a composite superabsorbent resin with an additional water absorption capacity of 12.8 parts;

[0273] The preparation method of the modified aeolian sand powder includes the following steps:

[0274] S1. Heat and dry the aeolian sand, calcine it at 800℃ and keep it at that temperature, then rapidly heat it to 1050℃ and keep it at that temperature, and finally cool it to obtain calcined aeolian sand.

[0275] S2. Calcined aeolian sand, metakaolin, and phosphogypsum powder are mixed and placed in a ball mill, and triethanolamine is added for grinding. The ratio of aeolian sand, metakaolin, phosphogypsum powder and triethanolamine is 75:23:2:0.03 to obtain composite powder.

[0276] S3. Add sodium silicate to deionized water and stir ultrasonically to obtain a water glass solution;

[0277] S4. Spray the water glass solution evenly onto the composite powder until it solidifies to obtain modified aeolian sand powder;

[0278] The preparation method of the base material includes the following steps:

[0279] S11. Mix aeolian sand with a particle size of 0.01-2.36 mm, fine aggregate of 2.36-4.75 mm, and coarse aggregate of 4.75-26.5 mm in a certain proportion. Cover the mixture with plastic wrap and let it sit for 6 hours to fully impregnate the surface, thus obtaining an impregnated mixture.

[0280] S12. Mix the superabsorbent resin, cement and modified aeolian sand powder in a certain proportion until uniform, and obtain the mixture;

[0281] S13. Mix and stir the mixtures obtained from S11 and S12 until uniform, then cure under static pressure to obtain the base material.

[0282] Comparative Example 6:

[0283] A base material, comprising the following parts by weight:

[0284] Aeolian sand: 627.3 samples;

[0285] Fine aggregate: 1045.3 parts;

[0286] Coarse aggregate: 3524 parts;

[0287] Modified aeolian sand powder: 231.2 parts;

[0288] Cement: 77.1 parts;

[0289] Superabsorbent polymer: 0.64 parts;

[0290] Water: 443 portions;

[0291] The superabsorbent resin is a composite superabsorbent resin with an additional water absorption capacity of 12.8 parts;

[0292] The preparation method of the modified aeolian sand powder includes the following steps:

[0293] S1. Heat and dry the aeolian sand, calcine it at 800℃ and keep it at that temperature, then rapidly heat it to 1050℃ and keep it at that temperature, and finally cool it to obtain calcined aeolian sand.

[0294] S2. Calcined aeolian sand, metakaolin, and phosphogypsum powder are mixed and placed in a ball mill, and triethanolamine is added for grinding. The ratio of aeolian sand, metakaolin, phosphogypsum powder and triethanolamine is 75:23:2:0.03 to obtain composite powder.

[0295] S3. Add polyvinyl acetate to deionized water, add emulsifier and ultrasonically stir to obtain polyvinyl acetate emulsion;

[0296] S4. Spray the polyvinyl acetate emulsion evenly onto the composite powder until it solidifies to obtain modified aeolian sand powder.

[0297] The preparation method of the base material includes the following steps:

[0298] S11. Mix aeolian sand with a particle size of 0.01-2.36 mm, fine aggregate of 2.36-4.75 mm, and coarse aggregate of 4.75-26.5 mm in a certain proportion. Cover the mixture with plastic wrap and let it sit for 6 hours to fully impregnate the surface, thus obtaining an impregnated mixture.

[0299] S12. Mix the superabsorbent resin, cement and modified aeolian sand powder in a certain proportion until uniform, and obtain the mixture;

[0300] S13. Mix and stir the mixtures obtained from S11 and S12 until uniform, then cure under static pressure to obtain the base material.

[0301] The modified aeolian sand road base materials prepared in Examples 1-9 were subjected to compaction tests. The specific method was as follows: the modified aeolian sand road base materials were subjected to compaction tests according to the method in the "Test Procedure for Inorganic Binder Stabilized Materials for Highway Engineering" (JTG 3441-2024). The moisture content-dry density relationship curve of the modified aeolian sand road base materials was plotted to determine the optimal moisture content and maximum dry density of the modified aeolian sand road base materials.

[0302] The proposed cementitious material (cement + modified aeolian sand powder) content is 6%. The water content in Examples 1-9 is 8.4-10.4%, 6.5-10%, 5.7-9.7%, 7.6-10.6%, 7.8-9.5%, 6.3-9.8%, 8.6-10.4%, 7.9-9.9%, and 6.2-10.5%, respectively. The compaction test equipment parameters (refer to T0804-1 Method C) are as follows: hammer mass: 4.5 kg; hammer impact diameter: 50 mm; hammer drop height: 450 mm; compaction cylinder dimensions: inner diameter 152 mm, height 170 mm, volume 2177 mL; number of impact layers: 3; number of impacts per layer: 98; average unit compaction energy: 2.677 J; allowable nominal maximum particle size: 37.5 mm.

[0303] One day before the test, a representative sample of 2000g was taken to determine the natural moisture content of the aggregate. On the day of the test, about 30kg of the sieved aggregate was taken out using the quartering method and then divided into 5 equal parts. The amount of water to be added to the mixture was calculated according to the 5 predetermined different moisture contents. The amount of water to be added was calculated according to formula (T0804-1). Then, the water was evenly sprayed onto the surface of the aggregate with a sprayer and mixed evenly. The mixture was then placed in a plastic bag and sealed for 6 hours.

[0304]

[0305] Where: m w - Amount of water to be added to the mixture (g); m n - The mass (g) of aggregate in the mixture, with an initial moisture content of w n That is, the air-dried moisture content (%); m c - The mass (g) of cementitious material in the mixture, and its original moisture content w c w - The required moisture content (%) of the mixture.

[0306] Add the required cementitious material to the impregnated mixture and mix thoroughly with a small shovel, trowel, or other tools until homogeneous. The cementitious material should be added one by one before the sample is compacted. For samples with cement, the compaction test should be completed within 1 hour after mixing. Take 1 / 3 of the mixture using the quartering method and add it to the test barrel. Level the surface and tamp it slightly. Set the number of hammer blows per layer to 98 for the first layer. After the first layer is compacted, roughen the surface of the compacted layer. Repeat the above steps to compact the remaining two layers of the sample. After compaction, use a demolding device to push the sample out of the barrel. Take two representative samples from the inside of the sample from top to bottom and place them in a 110℃ oven to determine their moisture content.

[0307] The formulas for calculating moisture content and dry density are as follows:

[0308]

[0309] In the formula: ρ w -Stable material wet density (g / cm³) 3 m1 - Total weight of test container and sample (g); m2 - Mass of test container (g); V - Volume of test container (cm³) 3 ).

[0310]

[0311] In the formula: ρ d - The dry density of the sample (g / cm³) 3 w - moisture content of the sample.

[0312] As shown in Table 1, each mixture has an optimum moisture content. When the mixture reaches its optimum moisture content, the water film covering the aggregate particles acts as a lubricant, minimizing frictional resistance between particles, resulting in more uniform surface wetting, and achieving maximum compaction. The optimum moisture content and maximum dry density of the mixture increase with increasing modified aeolian sand powder dosage. This is due to the large surface area and low density of the modified aeolian sand powder, as well as the compaction of aggregates within the mixture during mixing and compaction caused by the ball-bearing effect of the modified aeolian sand powder. The optimum moisture content and maximum dry density increase after incorporating superabsorbent polymer (SAP), which is related to the water absorption and release behavior of SAP itself. As the amount of SAP increases, the optimum moisture content and maximum dry density of each group decrease. This is related to the water absorption characteristics of SAP. As the amount of additional water introduced increases, the optimum moisture content and maximum dry density of each group show a trend of first increasing and then decreasing. This is because when the amount of additional water introduced is greater than the amount of water absorbed by SAP in the mixture, it will lead to an increase in the mixing water of the entire mixture system, causing the optimum moisture content and maximum dry density to decrease.

[0313] 1. Unconfined compressive strength: The modified aeolian sand road base material prepared was subjected to compressive strength test according to the method in the "Test Procedure for Inorganic Binder Stabilized Materials for Highway Engineering" (JTG 3441-2024).

[0314]

[0315] Where: Rc - unconfined compressive strength of the specimen (MPa); P - maximum pressure at specimen failure (N); A - cross-sectional area of ​​the specimen (mm²) 2 A = ΠD 2 / 4; D - Diameter of the specimen (mm).

[0316] The compressive strength of the modified aeolian sand road base material was compared by setting the same cementitious material dosage of 6%. The experimental results are shown in Table 1.

[0317] As can be seen from the test results in Table 1, the modified aeolian sand road base material prepared by the method of the present invention can meet the compressive strength requirements of secondary and lower grade road bases after 7 days of curing. According to the "Technical Specifications for Construction of Highway Pavement Base" (JTG / T F20-2015), under the same test conditions, the compressive strength of the modified aeolian sand road base material is better than that of cement-stabilized aeolian sand and gravel with kaolin.

[0318] Drying shrinkage performance: The test used a drying shrinkage chamber capable of measuring temperature and humidity changes. The chamber parameters were: controlled temperature 20±0.5℃, relative humidity 60±5%. After curing, the surface moisture of the specimens was wiped off, and their initial mass was measured. The mass m was measured at 2h, 6h, 12h, 24h, 48h, 72h, 96h, 120h, 144h, and 168h after the start of the test, starting from the time of placement in the drying shrinkage chamber. i And collect the shrinkage displacement deformation δ i After the drying shrinkage is complete, the standard specimens are placed in an oven and dried until they reach a constant weight of m. p .

[0319] Water loss rate: ω i =(m i -m i+1 ) / m p

[0320] Drying strain: ε i =δ i / l

[0321] Shrinkage coefficient: α di =ε i / ω i

[0322] Total shrinkage coefficient:

[0323] In the formula: w i -Water loss rate of the i-th time (%); δ i - The i-th drying shrinkage displacement deformation (mm); ε i - The i-th drying shrinkage strain (με); α di - The shrinkage coefficient of the i-th drying cycle (με / %); m i - Mass of the i-th standard specimen (g); l - Length of the standard specimen (mm); m p -Standard specimens were dried to constant weight (g).

[0324] Table 1. Experimental results of each embodiment and comparative example.

[0325]

[0326] As can be seen from Table 1, the modified aeolian sand road base material has stronger resistance to drying shrinkage than the cement-kaolin stabilized aeolian sand gravel base material.

[0327] According to the "Technical Specifications for Construction of Highway Pavement Base Course" (JTGT F20-2015), the 7-day unconfined compressive strength of Class II and below highways should be greater than 2.5 MPa. The results of the above examples show that all groups met the specifications, indicating that the modified aeolian sand road base material provided by this invention can effectively release the potential activity of aeolian sand and improve its utilization rate. In Example 5, the 7-day unconfined compressive strength reached its maximum, increasing by 133.1% compared to the aeolian sand powder modified with water glass-polyvinyl acetate emulsion without surface spraying in Comparative Example 4. This is because grinding the aeolian sand increases the amount of active components such as silica and activated alumina on its surface. Spraying water glass-polyvinyl acetate emulsion disrupts the surface structure of the aeolian sand (covalent bonds such as Si-O-Si, Al-O-Al, and Si-O-Al), making Ca... 2+ Al 3+ Si 4+ When the active substances dissolve, a condensation reaction occurs, polymerizing to form reaction products such as hydrated calcium silicate, hydrated calcium aluminate, or hydrated calcium sulfoaluminate. Furthermore, calcined aeolian sand, metakaolin, phosphogypsum powder, and triethanolamine produce a synergistic reinforcing effect, not only improving the grinding efficiency of the calcined aeolian sand but also promoting hydration, enhancing volume stability, and exhibiting nucleation and filling effects. In Example 2, the 7-day unconfined compressive strength was 115.4% higher than that of Comparative Example 3 without modified aeolian sand powder. In addition, in Example 6, the 27-day average shrinkage coefficient was 74.1% lower than that of Comparative Example 1 without modified aeolian sand powder and superabsorbent resin. This is because the phosphogypsum contains sulfur trioxide, which produces a suitable amount of volume expansion to resist shrinkage. Additionally, the release of water by the superabsorbent resin regulates the relative humidity inside the mixture, effectively alleviating the shrinkage phenomenon in the aeolian sand base layer.

[0328] Based on the above research results, the modified aeolian sand road base material prepared by this invention not only has excellent mechanical properties, but also effectively inhibits shrinkage cracking in the base layer, extends the service life of the road surface, reduces maintenance costs, has good economic benefits, and has broad development prospects.

Claims

1. A modified aeolian sand road base material, characterized in that, The modified aeolian sand road base material is composed of the following parts by weight: Aeolian sand: 620-635 parts; Fine aggregate: 1030–1055 parts; Coarse aggregate: 3510-3580 parts; Modified aeolian sand powder: 230-265 parts; Cement: 50-80 parts; Superabsorbent polymer: 0.32–0.96 parts; Water: 425–525 parts; The preparation method of the modified aeolian sand powder includes the following steps: S1. Heat and dry the aeolian sand, calcine it at 750-850℃ and keep it at that temperature, then rapidly heat it to 1000-1100℃ and keep it at that temperature, and finally cool it to obtain calcined aeolian sand. S2. Calcined aeolian sand, metakaolin, and phosphogypsum powder are mixed and placed in a ball mill, and triethanolamine is added for grinding to obtain composite powder; S3. Add sodium silicate and polyvinyl acetate to deionized water, add emulsifier and stir ultrasonically to obtain water glass-polyvinyl acetate emulsion; S4. Spray the water glass-polyvinyl acetate emulsion evenly onto the composite powder until it solidifies to obtain modified aeolian sand powder.

2. The modified aeolian sand road base material according to claim 1, characterized in that: The ratio of aeolian sand, metakaolin, phosphogypsum powder, and triethanolamine in step S2 is 75: 22.5~23.5:1.5~2.5:0.02~0.04; The ratio of polyvinyl acetate to sodium silicate in step S3 is 1:2~2.

5.

3. The modified aeolian sand road base material according to claim 1, characterized in that: The modified aeolian sand powder has a specific surface area of ​​300-350 m². 2 / kg, with a particle size distribution of 1–100 μm.

4. The modified aeolian sand road base material according to claim 1, characterized in that: The aeolian sand has a particle size range of 0.075–0.3 mm and an apparent density of 2.6–2.7 g / cm³. 3 The mud content is 9.0%–9.2%, and the water absorption rate is 0.47%–0.72%.

5. The modified aeolian sand road base material according to claim 1, characterized in that: The fine aggregate has a particle size range of 2.36–4.75 mm and an apparent density of 2.6–2.7 g / cm³. 3 Crushing value 19-19.5%, needle-like and flaky content 14-14.5%, water absorption rate 0.75-0.8%.

6. The modified aeolian sand road base material according to claim 1, characterized in that: The coarse aggregate has a particle size range of 4.75–9.5 mm and 9.5–26.5 mm; wherein the apparent density of the 4.75–9.5 mm crushed stone is 2.7–2.8 g / cm³. 3 The crushing value is 17.5–18%, the needle-like and flaky content is 13–14%, and the water absorption rate is 0.75–0.8%; the apparent density of the 9.5–26.5 mm crushed stone is 2.6–2.7 g / cm³. 3 Crushing value 19.5-20.5%, needle-like and flaky content 11.5-12.5%, water absorption rate 0.2-0.25%.

7. The modified aeolian sand road base material according to claim 1, characterized in that: The cement is P·O42.5 ordinary Portland cement.

8. The modified aeolian sand road base material according to claim 1, characterized in that: The superabsorbent resin includes any one or more of ionic superabsorbent resin, nonionic superabsorbent resin, and composite superabsorbent resin; the superabsorbent resin has an additional water absorption capacity of 10 to 30 times and a particle size range of 80 to 100 mesh.

9. The method for preparing modified aeolian sand road base material according to claim 1, characterized in that, Includes the following steps: S11. Mix aeolian sand with a particle size of 0.01-2.36 mm, fine aggregate of 2.36-4.75 mm, coarse aggregate of 4.75-26.5 mm and water in a certain proportion and stir evenly. Cover the mixture with plastic wrap and let it sit for 5-7 hours to fully impregnate the surface to obtain the impregnated mixture. S12. Mix the superabsorbent resin, cement and modified aeolian sand powder in a certain proportion until uniform, and obtain the mixture; S13. Mix and stir the mixtures obtained from S11 and S12 until uniform, then cure under static pressure to obtain modified aeolian sand road base material.

Images