Fluorite tailing material fatigue-resistant water-stable base and preparation method thereof

Abstract

The application discloses a kind of fluorite tailing material fatigue-resistant water-stable base and preparation method thereof.Belongs to the technical field of solid waste utilization.Preparation of the fluorite tailing material fatigue-resistant water-stable base aggregate ratio is as follows: gravel, river sand, fluorite tailing material and tap water quality ratio is as follows: 55-65 wt%, 30-35 wt%, 5-10 wt% and 40-45 wt% tap water.In the application, fluorite tailings are used as raw materials for building materials, which is a reasonable way of resource utilization, and is also an inevitable demand for promoting ecological protection and high-quality development in the Yellow River Basin.Compared with traditional natural materials, it can also reduce carbon emissions and production energy consumption.When applied to water-stable base, it improves its fatigue resistance, prolongs the service life of water-stable base and improves economic efficiency.

Description

Technical Field

[0001] This invention belongs to the field of solid waste utilization technology, specifically relating to a fatigue-resistant water-stabilized base course for fluorite tailings materials and its preparation method. Background Technology

[0002] Water-stabilized base course, also known as cement-stabilized crushed stone base course, is the most widely used material in highway pavement base courses. As the load-bearing foundation of a road, it is inevitably subject to fatigue cracking under cyclic loading during service. These cracks can cause irreversible structural and functional defects, shortening the road's service life. When the amount of cementitious material is low, its hydration products cannot effectively fill the numerous voids in the mixture, reducing the integrity and fatigue resistance of the water-stabilized base course. Furthermore, cement is the main cementitious material in water-stabilized base courses, and excessive cement content can lead to cracking due to cement's self-shrinkage and thermal shrinkage. Additionally, its carbon emissions and operating costs are relatively high.

[0003] Fluorite tailings, a byproduct of hydrofluoric acid production, are generated in large quantities during the process and have become a major solid waste, with accumulated stockpiles exceeding 10 billion tons and an annual output of 1.2 billion tons. Improper handling can cause water pollution, land occupation, and pose a potential geological hazard, necessitating resource utilization. As a high-silicon industrial waste, fluorite tailings are rich in silicon, with a silicon dioxide content exceeding 91%. The particle size distribution of fluorite tailings falls between that of cement and fine aggregate, allowing it to function as a good filler in cement mortar systems. Its mineral composition, primarily composed of quartz and feldspar, has the potential to react with water to form a strong phase. Under alkaline conditions, the activity of fluorite tailings can be activated, exhibiting certain cementitious properties. Its application in water-stabilized base courses could be considered, resulting in a denser and more uniform microstructure, improving the problem of excessive porosity in water-stabilized base courses, and offering advantages such as reduced operating costs, reduced carbon emissions, and reduced cement hydration shrinkage cracks.

[0004] Chinese invention patent CN115745541A discloses an ultrafine tailings-based water-stabilized layer material and its preparation method. The method mainly uses iron tailings combined with crushed stone, attapulgite, metakaolin, cement, lime, silica fume, and an ionic soil stabilizer to prepare the water-stabilized layer material. The tailings used are primarily tailings sludge obtained after iron tailings sorting, and multiple materials are used to enhance its activity. The water-stabilized layer material prepared by this patent's technical solution suffers from low density and weak fatigue resistance. Summary of the Invention

[0005] To address the aforementioned technical problems of low density and insufficient fatigue resistance in existing water-stabilized base courses, this invention provides a fatigue-resistant water-stabilized base course made of fluorite tailings and its preparation method.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: a sludge gasification slag activated cementitious material anti-fatigue water-stabilized base material, comprising the following raw materials in the following proportions: crushed stone 55%-65%wt, river sand 30%-35%wt, and fluorite tailings material 5%-10%wt.

[0007] Furthermore, the particle size of the crushed stone is 5mm-10mm, and the particle size of the river sand is no greater than 1.5mm.

[0008] Furthermore, the fluorite tailings material includes the following four proportions: (1) 60%-70% wt of fluorite tailings, 5%-10% wt of desulfurized gypsum, 10%-20% wt of steel slag, and 5%-10% wt of water glass; (2) 60%-70% wt of fluorite tailings, 5%-10% wt of desulfurized gypsum, 10%-20% wt of steel slag, and 5%-10% wt of sodium hydroxide; (3) 60%-70% wt of fluorite tailings, 5%-10% wt of desulfurized gypsum, 10%-20% wt of carbide slag, and 5%-10% wt of sodium hydroxide; (4) 60%-70% wt of fluorite tailings, 5%-10% wt of desulfurized gypsum, 10%-20% wt of carbide slag, and 5%-10% wt of water glass.

[0009] Furthermore, the fluorite tailings are powder with a particle size ≤0.08mm, and the sieve residue is 10%–20%, with a specific surface area of ​​2800–3300 cm². 2 / g.

[0010] Furthermore, the desulfurized gypsum has a fineness of 0.08 mm and a sieve residue of ≤10.5%; the cement is silicate cement with a strength grade of 42.5.

[0011] A method for preparing a fatigue-resistant water-stabilized base course for fluorite tailings materials includes the following steps:

[0012] S1: Weigh any one of the following four proportions of raw materials from the fluorite tailings: (1) 60%-70% wt of fluorite tailings, 5%-10% wt of desulfurized gypsum, 10%-20% wt of steel slag, and 5%-10% wt of water glass; (2) 60%-70% wt of fluorite tailings, 5%-10% wt of desulfurized gypsum, 10%-20% wt of steel slag, and 5%-10% wt of sodium hydroxide; (3) 60% wt of fluorite tailings. -70%wt, desulfurized gypsum 5%-10%wt, carbide slag 10%-20%wt, sodium hydroxide 5%-10%wt; (4). fluorite tailings 60%-70%wt, desulfurized gypsum 5%-10%wt, carbide slag 10%-20%wt, water glass 5%-10%wt; The weighed fluorite tailings material is mixed with tap water and placed in a clean slurry mixing pot and stirred evenly to obtain fluorite tailings material slurry with the target water-cement ratio;

[0013] S2: Pour the fluorite tailings slurry from step S1 into the steel mold in several batches, and use the vibration table to remove air bubbles from the cementitious slurry in the steel mold, and scrape the surface smooth; place it in an indoor film-covered curing room, and after demolding, place it in a standard curing box to cure until the target age, and demold to obtain fluorite tailings material test blocks;

[0014] S3: The compressive strength of the fluorite tailings slurry test blocks that have been cured to the specified age is tested, and the fluorite tailings material ratio is optimized considering the requirements of actual construction for its fluidity, stability and setting time.

[0015] S4: Mix 55%-65%wt of crushed stone, 30%-35%wt of river sand and 5%-10%wt of fluorite tailings material and conduct a compaction test to determine its optimum moisture content and maximum dry density.

[0016] S5: Calculate the amount of each raw material based on the optimum moisture content and maximum dry density; thoroughly mix the crushed stone, river sand, and fluorite tailings materials to obtain the fatigue-resistant water-stabilized base course mixture of fluorite tailings materials.

[0017] S6: Place the mixture from step 5 into a press for static pressing and then place it in a standard curing chamber for curing until the target age. Demold the mixture to obtain a fatigue-resistant water-stabilized base layer test block of fluorite tailings material.

[0018] S7: Place the cured specimens on the MTS testing machine for unconfined compressive strength test and cyclic load test;

[0019] S8: Perform fatigue performance analysis on the test block.

[0020] Furthermore, in step S1, the mass of tap water is 40%-45% of the fluorite tailings slurry.

[0021] In step S2, the curing time is 24 hours; the curing standard is a temperature of 20℃±1℃ and a relative humidity of not less than 90%.

[0022] Furthermore, in step S3, the compressive strength test is performed using an integrated flexural and compressive strength testing machine with a loading speed of 1 kN / s;

[0023] The specific process of the compaction test in step S4 is as follows: First, the crushed stone and river sand are watered and left to simmer for 2 hours, then mixed with fluorite tailings material; and then placed into the compaction bucket in 5 batches, with each batch being compacted 27 times in each layer; finally, the compacted specimen is removed using a demolding device.

[0024] Furthermore, in step S5, before the mixing process, 98%-99% of the water required for the optimal moisture content is added to the crushed stone and river sand to allow them to settle. Then, fluorite tailings material and the remaining water are added to the moist mixture.

[0025] In step S6, the loading rate of the press is 1 mm / min;

[0026] In step S7, the test block is placed in water for hydroponics on the last day of its curing period.

[0027] Furthermore, in step S7, the loading rate of the MTS testing machine used in the unconfined compressive strength test is set to 1 mm / min;

[0028] In step S7, during the cyclic loading test, the MTS testing machine is set with a preload of 500N at the beginning of the test. During the test, the load is applied at a displacement of 0.002mm / s to the stress amplitude corresponding to 70% of the peak stress of the water-stabilized base course specimen under uniaxial compression. Then, the load is unloaded at a displacement of 0.002mm / s to the stress amplitude corresponding to 20% of the peak stress of the water-stabilized base course specimen under uniaxial compression (the boundary between the compaction stage and the linear elastic stage). This process is considered as one cycle.

[0029] Step S8 in fatigue performance analysis mainly includes the relationship between elastic modulus, peak strain, residual plastic deformation and total absorbed energy, elastic deformation energy and dissipated energy as a function of the number of cycles.

[0030] Compared with the prior art, the beneficial effects of the present invention using the above technical solution are as follows: When fluorite tailings partially replace the water-stabilized base course material, the active fine powder contained therein undergoes secondary hydration under alkaline conditions, generating CSH gel at the interface. The filling effect of the fine powder also has a certain impact on the strength improvement of the water-stabilized base course. Furthermore, the large amount of unhydrated powder contained therein can play a "micro-aggregate effect" during the early strength development process, making the aggregate-cement slurry interface transition zone more compact and reducing the loose structure. Therefore, it can be used as an aggregate to fill the voids between aggregates, reducing the internal porosity of the water-stabilized base course, improving its compactness, and thus improving the fatigue resistance of the water-stabilized base course.

[0031] This invention uses fluorite tailings, which are abundant but currently have limited resource utilization methods. Its active components are mainly feldspar components, and the reaction principle under alkali activation is quite different from that of iron tailings sediment. In addition, fluorite tailings particles can also play a role in filling and compacting in the water-stabilized base course, significantly improving the fatigue resistance of the water-stabilized base course.

[0032] Replacing cement with fluorite tailings in the preparation of water-stabilized layers can, on the one hand, increase the amount of cementitious material used in water-stabilized base layers under the same cost conditions, thereby improving the fatigue resistance of the water-stabilized base layers and preparing a fatigue-resistant water-stabilized base layer material. On the other hand, it can realize the resource utilization of fluorite tailings, alleviate environmental pressure, and has important economic and environmental benefits.

[0033] In summary, the present invention uses treated fluorite tailings as a water-stabilized base course material, which not only reduces costs and improves economic benefits, but also increases the comprehensive utilization rate of solid waste. Attached Figure Description

[0034] Figure 1 This is a particle size distribution diagram of fluorite tailings. Detailed Implementation

[0035] The present invention will be further described below in conjunction with the specification and specific preferred embodiments, but this does not limit the scope of protection of the present invention.

[0036] Example 1

[0037] A fatigue-resistant water-stabilized base course for fluorite tailings and its preparation method, specifically including the following steps:

[0038] S1. Weigh out 60%-70% wt fluorite tailings, 5%-10% wt desulfurized gypsum, 10%-20% wt steel slag, 5%-10% wt water glass, and 40%-45% wt tap water respectively, mix them, and pour them into a slurry mixing pot. Stir at low speed for 120 seconds, stop for 15 seconds, and scrape the slurry from the blades and pot walls. Then stir at high speed for 120 seconds to obtain fluorite tailings slurry. The particle size distribution diagram of fluorite tailings is shown below. Figure 1 As shown.

[0039] S2. Pour the fluorite tailings slurry into the steel mold in several batches, and vibrate it on a vibrating table for 2 minutes to remove air bubbles from the slurry in the steel mold. Scrape the surface smooth, place it indoors for film curing for 24 hours, demold it and place it in a standard curing room with a temperature of 20℃±1℃ and a relative humidity of not less than 90% to cure until the target age.

[0040] S3: Test the compressive strength, fluidity, stability and setting time of the fluorite tailings slurry sample blocks.

[0041] S4. Weigh 55%-65% wt of crushed stone and 30%-35% wt of river sand, sprinkle with water and let it sit for 2 hours, then mix with 5%-10% wt of fluorite tailings; add to a compaction hopper in 5 portions, compacting 27 times each time, and remove the compacted specimen with a demolding device to measure its optimum moisture content and maximum dry density. In the fluorite tailings material, fluorite tailings account for 60%-70% wt, desulfurized gypsum accounts for 5%-10% wt, steel slag accounts for 10%-20% wt, and water glass accounts for 5%-10% wt.

[0042] S5. Calculate the amount of crushed stone and river sand according to the optimum moisture content and maximum dry density, spray water and let it sit for 2 hours, then mix it with fluorite tailings material, mix it evenly, then put it into a press with a loading rate of 1mm / min for static pressing and molding, and place it in a standard curing box for curing until the day before the target age for water curing.

[0043] S6. Place the cured specimens on the MTS testing machine for unconfined compressive strength test and cyclic loading test. The loading rate of the MTS testing machine used for the unconfined compressive strength test is set to 1 mm / min. The MTS testing machine used for the cyclic loading test is preloaded with 500 N at the beginning of the test; during the test, the load is applied at a displacement of 0.002 mm / s to the stress amplitude corresponding to 70% of the peak stress of the water-stabilized base course specimen under uniaxial compression, and then unloaded at a displacement of 0.002 mm / s to the stress amplitude corresponding to 20% of the peak stress of the water-stabilized base course specimen under uniaxial compression (the boundary between the compaction stage and the linear elastic stage). This process is considered one cycle.

[0044] S7. The fatigue-resistant water-stabilized base course of fluorite tailings material is analyzed by examining the relationship between elastic modulus, peak strain, residual plastic deformation, total absorbed energy, elastic deformation energy, and dissipated energy as a function of the number of cycles.

[0045] Table 1. Mix proportions and compressive strengths of water glass-steel slag-fluorite tailings slurry specimens.

[0046]

[0047] Table 2. Unconfined compressive strength and fatigue life of water-glass-steel slag-fluorite tailings-based fatigue-resistant water-stabilized base course.

[0048]

[0049] Example 2

[0050] A fatigue-resistant water-stabilized base course for fluorite tailings and its preparation method, specifically including the following steps:

[0051] S1. Weigh out 60%-70%wt of fluorite tailings, 5%-10%wt of desulfurized gypsum, 10%-20%wt of steel slag, 5%-10%wt of sodium hydroxide and 40%-45%wt of tap water respectively, mix them and pour them into a clean slurry mixing pot. Stir at low speed for 120s, stop for 15s, and scrape the slurry on the blades and pot wall at the same time. Then stir at high speed for 120s to obtain fluorite tailings material slurry.

[0052] S2. Pour the fluorite tailings slurry into the steel mold in several batches, and vibrate it on a vibrating table for 2 minutes to remove air bubbles from the slurry in the steel mold. Scrape the surface smooth, place it indoors for film curing for 24 hours, demold it and place it in a standard curing room with a temperature of 20℃±1℃ and a relative humidity of not less than 90% to cure until the target age.

[0053] S3: Test the compressive strength, fluidity, stability and setting time of the fluorite tailings slurry sample blocks.

[0054] S4. Weigh 55%-65% wt of crushed stone and 30%-35% wt of river sand, sprinkle with water and let it sit for 2 hours, then mix with 5%-10% wt of fluorite tailings. Place the mixture into a compaction hopper in 5 batches, compacting 27 times each time. Remove the compacted specimen using a demolding device and measure its optimum moisture content and maximum dry density. In the fluorite tailings material, fluorite tailings account for 60%-70% wt, desulfurized gypsum accounts for 5%-10% wt, steel slag accounts for 10%-20% wt, and sodium hydroxide accounts for 5%-10% wt.

[0055] S5. Calculate the amount of crushed stone and river sand according to the optimum moisture content and maximum dry density, spray water and let it sit for 2 hours, then mix it with fluorite tailings material, mix it evenly, then put it into a press with a loading rate of 1mm / min for static pressing and molding, and place it in a standard curing box for curing until the day before the target age for water curing.

[0056] S6. Place the cured specimens on the MTS testing machine for unconfined compressive strength test and cyclic loading test. The loading rate of the MTS testing machine used for the unconfined compressive strength test is set to 1 mm / min. The MTS testing machine used for the cyclic loading test is preloaded with 500 N at the beginning of the test; during the test, the load is applied at a displacement of 0.002 mm / s to the stress amplitude corresponding to 70% of the peak stress of the water-stabilized base course specimen under uniaxial compression, and then unloaded at a displacement of 0.002 mm / s to the stress amplitude corresponding to 20% of the peak stress of the water-stabilized base course specimen under uniaxial compression (the boundary between the compaction stage and the linear elastic stage). This process is considered one cycle.

[0057] S7. The fatigue-resistant water-stabilized base course of fluorite tailings material is analyzed by examining the relationship between elastic modulus, peak strain, residual plastic deformation, total absorbed energy, elastic deformation energy, and dissipated energy as a function of the number of cycles.

[0058] Table 3. Mix proportions and compressive strengths of sodium hydroxide-steel slag-fluorite tailings paste test blocks

[0059]

[0060] Table 4 Unconfined compressive strength and fatigue life of fatigue-resistant water-stabilized base course material composed of sodium hydroxide-steel slag-fluorite tailings.

[0061]

[0062]

[0063] Example 3

[0064] A fatigue-resistant water-stabilized base course for fluorite tailings and its preparation method, specifically including the following steps:

[0065] S1. Weigh out 60%-70%wt of fluorite tailings, 5%-10%wt of desulfurized gypsum, 10%-20%wt of carbide slag, 5%-10%wt of sodium hydroxide and 40%-45%wt of tap water respectively, mix them and pour them into a slurry mixing pot. Stir at low speed for 120s, stop for 15s, and scrape the slurry from the blades and the pot wall at the same time. Then stir at high speed for 120s to obtain fluorite tailings material slurry.

[0066] S2. Pour the fluorite tailings slurry into the steel mold in several batches, and vibrate it on a vibrating table for 2 minutes to remove air bubbles from the slurry in the steel mold. Scrape the surface smooth, place it indoors for film curing for 24 hours, demold it and place it in a standard curing room with a temperature of 20℃±1℃ and a relative humidity of not less than 90% to cure until the target age.

[0067] S3: Test the compressive strength, fluidity, stability and setting time of the fluorite tailings slurry sample blocks.

[0068] S4. Weigh 55%-65% wt of crushed stone and 30%-35% wt of river sand, sprinkle with water and let it sit for 2 hours, then mix with 5%-10% wt of fluorite tailings; add to a compaction hopper in 5 portions, compacting 27 times each time, and remove the compacted specimen with a demolding device to measure its optimum moisture content and maximum dry density. In the fluorite tailings material, fluorite tailings account for 60%-70% wt, desulfurized gypsum accounts for 5%-10% wt, calcium carbide slag accounts for 10%-20% wt, and sodium hydroxide accounts for 5%-10% wt.

[0069] S5. Calculate the amount of crushed stone and river sand according to the optimum moisture content and maximum dry density, spray water and let it sit for 2 hours, then mix it with fluorite tailings material, mix it evenly, then put it into a press with a loading rate of 1mm / min for static pressing and molding, and place it in a standard curing box for curing until the day before the target age for water curing.

[0070] S6. Place the cured specimens on the MTS testing machine for unconfined compressive strength test and cyclic loading test. The loading rate of the MTS testing machine used for the unconfined compressive strength test is set to 1 mm / min. The MTS testing machine used for the cyclic loading test is preloaded with 500 N at the beginning of the test; during the test, the load is applied at a displacement of 0.002 mm / s to the stress amplitude corresponding to 70% of the peak stress of the water-stabilized base course specimen under uniaxial compression, and then unloaded at a displacement of 0.002 mm / s to the stress amplitude corresponding to 20% of the peak stress of the water-stabilized base course specimen under uniaxial compression (the boundary between the compaction stage and the linear elastic stage). This process is considered one cycle.

[0071] S7. The fatigue-resistant water-stabilized base course of fluorite tailings material is analyzed by examining the relationship between elastic modulus, peak strain, residual plastic deformation, total absorbed energy, elastic deformation energy, and dissipated energy as a function of the number of cycles.

[0072] Table 5. Mix proportions and compressive strengths of sodium hydroxide-carbide slag-fluorite tailings slurry test blocks.

[0073]

[0074] Table 6 Unconfined compressive strength and fatigue life of fatigue-resistant water-stabilized base course material composed of sodium hydroxide-carbide slag-fluorite tailings.

[0075]

[0076] Example 4

[0077] A fatigue-resistant water-stabilized base course for fluorite tailings and its preparation method, specifically including the following steps:

[0078] S1. Weigh out 60%-70%wt of fluorite tailings, 5%-10%wt of desulfurized gypsum, 10%-20%wt of carbide slag, 5%-10%wt of water glass and 40%-45%wt of tap water respectively, mix them and pour them into a slurry mixing pot. Stir at low speed for 120s, stop for 15s, and scrape the slurry from the blades and the pot wall at the same time. Then stir at high speed for 120s to obtain fluorite tailings material slurry.

[0079] S2. Pour the fluorite tailings slurry into the steel mold in several batches, and vibrate it on a vibrating table for 2 minutes to remove air bubbles from the slurry in the steel mold. Scrape the surface smooth, place it indoors for film curing for 24 hours, demold it and place it in a standard curing room with a temperature of 20℃±1℃ and a relative humidity of not less than 90% to cure until the target age.

[0080] S3: Test the compressive strength, fluidity, stability and setting time of the fluorite tailings slurry sample blocks.

[0081] S4. Weigh 55%-65% wt of crushed stone and 30%-35% wt of river sand, sprinkle with water and let it sit for 2 hours, then mix with 5%-10% wt of fluorite tailings; add to a compaction hopper in 5 portions, compacting 27 times each time, and remove the compacted specimen with a demolding device to measure its optimum moisture content and maximum dry density. In the fluorite tailings material, fluorite tailings account for 60%-70% wt, desulfurized gypsum accounts for 5%-10% wt, calcium carbide slag accounts for 10%-20% wt, and water glass accounts for 5%-10% wt.

[0082] S5. Calculate the amount of crushed stone and river sand according to the optimum moisture content and maximum dry density, spray water and let it sit for 2 hours, then mix it with fluorite tailings material, mix it evenly, then put it into a press with a loading rate of 1mm / min for static pressing and molding, and place it in a standard curing box for curing until the day before the target age for water curing.

[0083] S6. Place the cured specimens on the MTS testing machine for unconfined compressive strength test and cyclic loading test. The loading rate of the MTS testing machine used for the unconfined compressive strength test is set to 1 mm / min. The MTS testing machine used for the cyclic loading test is preloaded with 500 N at the beginning of the test; during the test, the load is applied at a displacement of 0.002 mm / s to the stress amplitude corresponding to 70% of the peak stress of the water-stabilized base course specimen under uniaxial compression, and then unloaded at a displacement of 0.002 mm / s to the stress amplitude corresponding to 20% of the peak stress of the water-stabilized base course specimen under uniaxial compression (the boundary between the compaction stage and the linear elastic stage). This process is considered one cycle.

[0084] S7. The fatigue-resistant water-stabilized base course of fluorite tailings material is analyzed by examining the relationship between elastic modulus, peak strain, residual plastic deformation, total absorbed energy, elastic deformation energy, and dissipated energy as a function of the number of cycles.

[0085] Table 7. Mix proportions and compressive strengths of water glass-carbide slag-fluorite tailings slurry test blocks

[0086]

[0087] Table 8. Unconfined compressive strength and fatigue life of water-glass-carbide slag-fluorite tailings material in a fatigue-resistant water-stabilized base course.

[0088]

[0089]

[0090] As can be seen from the table above, the water-stabilized base course prepared from fluorite tailings can not only partially replace cement but also has excellent fatigue resistance, realizing the resource utilization of fluorite tailings in the field of building materials.

[0091] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A fatigue-resistant, water-stable base course of a fluorite tailings material, characterized by: The raw materials include the following proportions: 55%-65%wt of crushed stone, 30%-35%wt of river sand, and 5%-10%wt of fluorite tailing material; The particle size of the crushed stone is 5mm-10mm, and the particle size of the river sand is not greater than 1.5mm; The fluorite tailing material is selected from any one of the following four groups: (1) fluorite tailing 60%-70%wt, desulfurization gypsum 5%-10%wt, steel slag 10%-20%wt, and water glass 5%-10%wt; (2) fluorite tailing 60%-70%wt, desulfurization gypsum 5%-10%wt, steel slag 10%-20%wt, and sodium hydroxide 5%-10%wt; (3) fluorite tailing 60%-70%wt, desulfurization gypsum 5%-10%wt, carbide slag 10%-20%wt, and sodium hydroxide 5%-10%wt; (4) fluorite tailing 60%-70%wt, desulfurization gypsum 5%-10%wt, carbide slag 10%-20%wt, and water glass 5%-10%wt; Fluorite tailings are powders with particle size of ≤0.08 mm and sieve residue of 10%~20%, specific surface area of 2800~3300 cm 2 / g.

2. A fatigue-resistant, water-stable base course of a fluorspar tailings material according to claim 1, characterised in that: The fineness of the desulfurization gypsum is 0.08mm, and the sieve residue is ≤10.5%; the cement is a silicate cement with a strength grade of 42.

5.

3. A method of preparing a fatigue resistant, water stable base of a fluorite tailings material as claimed in claim 1, characterised in that: The method includes the following steps: S1: any one of the following four groups of raw materials of the fluorite tailing material is selected for weighing: (1) fluorite tailing 60%-70%wt, desulfurization gypsum 5%-10%wt, steel slag 10%-20%wt, and water glass 5%-10%wt; (2) fluorite tailing 60%-70%wt, desulfurization gypsum 5%-10%wt, steel slag 10%-20%wt, and sodium hydroxide 5%-10%wt; (3) fluorite tailing 60%-70%wt, desulfurization gypsum 5%-10%wt, carbide slag 10%-20%wt, and sodium hydroxide 5%-10%wt; (4) fluorite tailing 60%-70%wt, desulfurization gypsum 5%-10%wt, carbide slag 10%-20%wt, and water glass 5%-10%wt; after weighing, the fluorite tailing material is mixed with tap water, stirred uniformly in a neat slurry stirring pot, and a fluorite tailing material slurry with a target water-cement ratio is obtained; S2: the fluorite tailing material slurry in step S1 is poured into a steel mold in batches, and the bubbles in the cementitious material slurry are discharged from the steel mold through vibration of a vibration table, the surface is scraped flat, and then placed in indoor film curing for curing until a target age in a standard curing box, and a fluorite tailing material test block is obtained after demolding; S3: the fluorite tailing material neat slurry test block cured to the age is subjected to compressive strength testing, and the fluorite tailing material proportioning is optimized considering the requirements of actual construction on its fluidity, stability, and setting time; S4: the crushed stone 55%-65%wt, the river sand 30%-35%wt, and the fluorite tailing material 5%-10%wt are mixed and then subjected to compaction test, and the optimal water content and the maximum dry density are measured; S5: the amount of each raw material is calculated according to the optimal water content and the maximum dry density; the crushed stone, the river sand, and the fluorite tailing material are fully stirred and mixed uniformly, and finally a fluorite tailing material fatigue-resistant water-stable base mixture is obtained. S6: Put the mixture in step 5 into the press for static pressure forming, and place it in a standard curing box for curing to the target age, and demold to obtain the fluorite tailings material fatigue-resistant water-stable base test block; S7: Place the test block cured to the age on the MTS testing machine for unconfined compressive strength test and cyclic loading test; S8: Analyze the fatigue performance of the test block.

4. A method of preparing a water stable fatigue resistant base course of a fluorite tailings material according to claim 3, characterised in that: The quality of tap water in step S1 is 40%-45% of the fluorite tailings material slurry; The film curing time in step S2 is 24h; the curing standard is temperature 20℃±1℃, and relative humidity not less than 90%.

5. A method of preparing a water stable fatigue resistant base course of a fluorite tailings material according to claim 4 characterised in that: The compressive strength test in step S3 uses a bending and compressive strength integrated machine, and the loading speed is 1KN / s; The specific process of the compaction test in step S4 is: first, sprinkle water on the gravel and river sand and soak for 2h, then mix with fluorite tailings material; and put into the compaction barrel in 5 times, each time 27 times of compaction; finally, take out the compaction test piece with the demolding device.

6. A method of preparing a water stable fatigue resistant base course of a fluorite tailings material according to claim 5, characterised in that: In step S5, 98%-99% of the water required for the optimum moisture content is added to the gravel and river sand before the stirring process, and then the fluorite tailings material and the remaining water are added to the wet mixture; The loading rate of the press in step S6 is 1mm / min; In step S7, the test block is placed in water on the last day of curing to the age.

7. A method of preparing a water stable fatigue resistant base course of a fluorspar tailings material according to claim 6 characterised in that: In step S7, the loading rate of the MTS testing machine used in the unconfined compressive strength test is set to 1mm / min; In step S7, in the cyclic loading test, the MTS testing machine used is set to a pre-load of 500N at the beginning of the test; during the test, the displacement loading method is used to load to the stress amplitude corresponding to 70% of the peak stress of the uniaxial compression water-stable base test block at a rate of 0.002mm / s, and then unload to the stress amplitude corresponding to 20% of the peak stress of the uniaxial compression water-stable base test block at a rate of 0.002mm / s, which is a cycle; In step S8, the fatigue performance analysis mainly includes the relationship between the elastic modulus, peak strain, residual plastic deformation, and total absorbed energy, elastic deformation energy and dissipation energy with the number of cycles.

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