Ultrahigh ductility lithium slag concrete and preparation method thereof

Abstract

The present application relates to the technical field of cement-based building materials, and particularly relates to a super-high ductility lithium slag concrete and a preparation method thereof, wherein each component comprises cement 390-450 parts, modified lithium slag powder 40-120 parts, fly ash 500-700 parts, quartz sand 300-500 parts, polyethylene fiber 10-20 parts, water-absorbing polymer 30-40 parts, high-efficiency water reducing agent 3-6 parts, thickening agent 1-3 parts and water 330-460 parts according to mass fraction. The present application adopts the above components, realizes the large deformation and multi-crack capacity of the super-high ductility lithium slag concrete through the activity excitation and mixing amount optimization of the lithium slag, the filling effect of the fly ash and the humidity adjusting function of the water-absorbing polymer, and introduces the polyethylene fiber, obtains the super-high ductility lithium slag concrete with high ductility and strain hardening characteristics, and the preparation method has the significant advantages of green environmental protection, low cost, high performance and the like, and is suitable for various building and engineering application scenes.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of cement-based building materials, and particularly relates to an ultra-high ductility lithium slag concrete and a preparation method thereof. BACKGROUND

[0002] Lithium slag is a large amount of industrial waste discharged in the production process of lithium salt industry (such as lithium carbonate, lithium chloride and lithium hydroxide, etc.), which is the residual material after lithium ore or spodumene is treated by high-temperature roasting and acid-alkali dissolution. About 8-10 tons of lithium slag will be produced for every ton of lithium carbonate. In recent years, the demand for lithium salt in China has grown rapidly, and the production of lithium slag has increased sharply. If not utilized, the large amount of lithium slag will not only occupy land resources, but also cause serious threat to the ecological environment, so it is urgent to develop effective resource utilization approaches for lithium slag.

[0003] Lithium slag has high pozzolanic activity and contains a certain amount of active CaO and SO3, so that it can have a secondary pozzolanic reaction with cement hydration products (such as Ca(OH)2) under appropriate conditions to generate new hydration products and improve the microstructure of the matrix. Based on the above characteristics, lithium slag can be used as a mineral admixture in cement-based materials to partially replace cement or other cementitious materials.

[0004] Patent CN202011402365.9 discloses a preparation method of lithium slag concrete. The method uses specific raw material ratio, including cement, fly ash, water, sand, gravel, and additional materials and modified lithium slag material. The modified lithium slag material is made of lithium slag powder, cyclohexylamine-based methyl triethoxysilane and ethyl cellulose. The lithium slag concrete of the patent has good bending resistance. The preparation method includes mixing and concrete preparation steps, aiming to improve the bending resistance of the product. However, when facing tensile or bending load, the plastic deformation capacity of the lithium slag concrete may be insufficient, leading to the risk of brittle fracture. In addition, the brittleness of the lithium slag concrete may affect its durability, especially in applications requiring high ductility.

[0005] Patent CN202111637600.5 discloses a method for preparing lithium slag concrete using industrial waste slag. The concrete includes lithium slag, alkali activator, water reducing agent, steel slag of different particle sizes and water. The lithium slag is a byproduct produced in the process of producing lithium sulfate by calcining spodumene and then using sulfuric acid method. The patent reasonably matches the raw materials, so that the obtained lithium slag concrete has a 28-day strength greater than 24.1 MPa and a fluidity greater than 189 mm, effectively utilizing resources and protecting the environment. However, the obtained concrete has insufficient ductility and has the risk of brittle fracture; lithium slag storage may cause environmental problems, requiring additional environmental protection measures; durability is limited by low toughness and crack resistance, affecting long-term performance.

[0006] Ultra-high ductile concrete (UHDC) is a new type of cement-based composite material with excellent mechanical properties and durability. It has attracted widespread attention due to its excellent tensile ductility and crack resistance. Unlike traditional concrete, which exhibits brittle fracture behavior, UHDC can exhibit significant strain hardening characteristics under tensile loading, forming multiple refined cracks at the micro level, thereby significantly improving its deformation performance and durability. In the face of the brittleness, environmental impact, and durability problems in the existing technology, the development of UHDC provides an innovative solution. SUMMARY

[0007] The purpose of the present application is to provide a kind of ultra-high ductile lithium slag concrete and its preparation method, the modified lithium slag powder after alkaline excitation is used as auxiliary cementitious material, the filling effect of fly ash is combined, and water-absorbing polymer is introduced to adjust humidity, polyethylene fiber realizes strain hardening, and the ultra-high ductile lithium slag concrete prepared has ultra-high tensile strain capacity and excellent strain hardening behavior.

[0008] To achieve the above purpose, the present application provides a kind of ultra-high ductile lithium slag concrete, each component is calculated according to mass fraction, including cement 390-450 parts, modified lithium slag powder 40-120 parts, fly ash 500-700 parts, quartz sand 300-500 parts, polyethylene fiber 10-20 parts, water-absorbing polymer 30-40 parts, superplasticizer 3-6 parts, thickening agent 1-3 parts and water 330-460 parts.

[0009] Preferably, the addition amount of cement accounts for 55-65% of the total mass of the ultra-high ductile lithium slag concrete.

[0010] The present application can ensure the early strength of the ultra-high ductile lithium slag concrete by appropriate cement content, and avoid the problem of increased shrinkage and decreased durability caused by excessive cement content.

[0011] Preferably, the addition amount of modified lithium slag powder is 10-20% of the total mass of the ultra-high ductile lithium slag concrete.

[0012] The modified lithium slag powder in the present application is alkaline activated by alkaline activator during modification, which improves SiO2, Al2O3 and CaO in the modified lithium slag powder, and gives the modified lithium slag good pozzolanic activity, and can react with the hydration product Ca(OH)2 to generate new C-S-H gel and ettringite, improve the micro-pore structure of the ultra-high ductile lithium slag concrete, and thus improve the strength and durability of the ultra-high ductile lithium slag concrete. At the same time, the modified lithium slag powder also has a certain filling effect, which can effectively fill the pores in the ultra-high ductile lithium slag concrete, further improving the compactness of the ultra-high ductile lithium slag concrete matrix.

[0013] Preferably, the polyethylene fiber has a length of 12-24mm, a diameter of 20-30μm, an aspect ratio of 500-800, an elongation at break of 2-3%, and a tensile strength of 2800-3500MPa.

[0014] In the present application, polyethylene fiber is used as the reinforcing material of the ultra-high ductility lithium slag concrete, and the interface adhesion and the bridging complementary residual energy of the polyethylene fiber / ultra-high ductility lithium slag concrete matrix are regulated by controlling the aspect ratio of the polyethylene fiber, so that the ultra-high ductility requirement of the lithium slag concrete can be achieved when the volume fraction of the polyethylene fiber is 1-2% of the total volume of the ultra-high ductility lithium slag concrete.

[0015] In the present application, the aspect ratio of the polyethylene fiber is controlled, and when the aspect ratio is too small, the polyethylene fiber often cannot play its high-strength role due to early pull-out from the cement matrix; when the aspect ratio is too large, the probability of fracture failure of the polyethylene fiber during pull-out will be increased, and the broken polyethylene fiber will no longer provide bridging effect.

[0016] Preferably, the water-absorbing polymer is a polyacrylic acid-acrylamide type high molecular water-absorbing resin, and has a particle size of 150-620μm. The dosage of the water-absorbing polymer (SAP) is 0.1-0.2% of the total mass of the ultra-high ductility lithium slag concrete.

[0017] The water-absorbing polymer added in the present application can release the absorbed water when the internal humidity is insufficient, prolong the hydration reaction, and prevent cracks caused by drying shrinkage. The SAP can effectively inhibit the generation of early drying shrinkage cracks and improve the overall crack resistance of the ultra-high ductility lithium slag concrete.

[0018] Preferably, the quartz sand is medium-fine sand, the particle size of the quartz sand is 0.2-0.6mm, the fineness modulus is 2.5-3.0, and the clay content is less than 1%.

[0019] In the present application, the quartz sand constitutes the skeleton structure of the ultra-high ductility lithium slag concrete, provides the necessary compactness and dimensional stability for the ultra-high ductility lithium slag concrete, and optimizes the fluidity of the ultra-high ductility lithium slag concrete by optimizing the particle shape and particle size distribution of the quartz sand. Compared with natural desert sand or river sand, the quartz sand has higher purity and more uniform particle size distribution, thereby significantly improving the mechanical properties and crack resistance of the ultra-high ductility lithium slag concrete.

[0020] Preferably, the particle size of the fly ash is 50-400μm, the specific surface area is 400-600m 2 / kg, and the fly ash is one or more of first-grade fly ash and second-grade fly ash.

[0021] The present invention utilizes active components in fly ash (such as SiO2 and Al2O3) to react with Ca(OH)2 to generate CSH gel and ettringite, thereby enhancing the density and durability of the ultra-high ductility lithium slag concrete matrix structure.

[0022] In this invention, the use of fly ash and modified lithium slag powder in combination can synergistically improve the mechanical properties and crack resistance of ultra-high-ductility lithium slag concrete through a secondary pozzolanic reaction, further enhancing ductility and durability. The tiny fly ash particles can fill the micropores in the ultra-high-ductility lithium slag concrete, reducing porosity and improving impermeability and frost resistance.

[0023] Preferably, the thickener is cellulose ether, the cellulose ether is hydroxypropyl methylcellulose ether, and the added amount of the thickener is 0.03-0.05% of the total mass of the ultra-high ductility lithium slag concrete.

[0024] The present invention uses hydroxypropyl methylcellulose ether as a thickener to improve the cohesiveness of ultra-high ductility lithium slag concrete and prevent construction defects caused by fiber or aggregate separation.

[0025] Preferably, the high-efficiency water reducer is a polycarboxylate water reducer with a water reduction rate of 30-40%, a solid content of 40-50%, a Na2SO4 content of <2wt%, and a CI - Content <0.01wt%.

[0026] The above-mentioned method for preparing ultra-high ductility lithium slag concrete comprises the following steps:

[0027] S1. Weigh 390-450 parts of cement, 40-120 parts of modified lithium slag powder, 500-700 parts of fly ash, 300-500 parts of quartz sand, 10-20 parts of polyethylene fiber, 30-40 parts of water-absorbing polymer, 3-6 parts of high-efficiency water reducer, 1-3 parts of thickener and 330-460 parts of water by mass;

[0028] S2. Add cement, modified lithium slag powder, quartz sand, fly ash and high-efficiency water reducer into a mixer and stir slowly for 3-5 minutes until the mixture is evenly mixed to obtain dry material;

[0029] S3. Add water to the dry material in S1 and continue to stir slowly for 2-3 minutes. After the dry material is liquefied, add a thickener and stir evenly to obtain a mixture;

[0030] S4. Slowly add polyethylene fiber to the mixture in S3 and stir rapidly for 2-3 minutes until the polyethylene fiber is evenly dispersed to obtain a slurry;

[0031] S5. Pour the slurry in S4 into a mold, vibrate to form it, and then seal it. After demoulding, cure it at room temperature for 28 days to obtain ultra-high ductility lithium slag concrete.

[0032] Preferably, in S1, the preparation step of the modified lithium slag powder is that the waste lithium slag is recovered and then subjected to crushing, fine grinding, washing and drying in sequence, the dried lithium slag powder is mixed with an alkaline activator for soaking, and after complete reaction, the modified lithium slag powder is obtained through screening.

[0033] Preferably, in S2 and S3, the rotating speed of slow stirring is 100-135 r / min.

[0034] Preferably, in S4, the rotating speed of fast stirring is 185-230 r / min.

[0035] Therefore, the present application adopts the above-mentioned ultra-high ductility lithium slag concrete and its preparation method, which has the following characteristics and excellent effects:

[0036] 1. The ultra-high ductility lithium slag concrete provided by the present application effectively improves the ductility of the ultra-high ductility lithium slag concrete by controlling the material ratio and the preparation method, so that it can withstand significant plastic deformation when subjected to tensile or bending load, thereby significantly improving the seismic performance and safety of the ultra-high ductility lithium slag concrete structure.

[0037] 2. The ultra-high ductility lithium slag concrete provided by the present application solves the environmental problem of lithium slag stockpiling by partially replacing cement with modified lithium slag powder, promotes the resource utilization of industrial waste slag, provides a new solution for low-carbon buildings, and promotes sustainable development.

[0038] 3. The modified lithium slag powder used in the present application has pozzolanic activity and filling effect, which can effectively improve the pore structure of the micro ultra-high ductility lithium slag concrete and optimize the performance of the interface transition zone, thereby improving the strength and durability of the ultra-high ductility lithium slag concrete, reducing production cost and carbon footprint.

[0039] 4. The preparation method provided by the present application is simple to operate, and the ultra-high ductility lithium slag concrete prepared by the method has excellent strain hardening and tensile ductility, with an axial tensile ductility of more than 3% and a crack width of 87-100 µm, which significantly improves the brittleness performance and crack control ability of the concrete.

[0040] 5. The preparation method provided by the present application is low-carbon, green and environmentally friendly, realizes the resource utilization of industrial waste slag, reduces the amount of ordinary portland cement, reduces carbon emissions, and has significant environmental and economic benefits.

[0041] The technical solutions of the present application will be further described in detail through examples. DETAILED DESCRIPTION

[0042] The application will be further described below with reference to examples. Unless otherwise defined, the technical terms or scientific terms used in the present application shall have the usual meaning understood by a person with ordinary skills in the art to which the present application belongs. The features mentioned above or the features mentioned in the specific examples can be combined in any manner, and these specific examples are only used to illustrate the present application and not to limit the scope of the present application. The raw materials used in the examples are well-known and commercially available unless otherwise specified.

[0043] The preparation steps of the modified lithium slag powder are as follows:

[0044] The waste lithium slag generated in the industrial production of lithium salt is recovered and sequentially subjected to crushing, fine grinding, washing and drying. The crushing is performed by coarse crushing followed by fine grinding. The coarse crushing is performed in an eccentric crusher, and the coarse crushed product is sieved using a stone sand screen to remove particles larger than 5 mm and retain the particles suitable for subsequent treatment for fine grinding. The fine grinding is performed in a rotary drum ball mill until lithium slag powder with a specific surface area of 1100-1200 m 2 / kg is obtained. The fine-ground lithium slag powder is sieved to remove particles that are not completely ground to ensure that the final lithium slag powder is fine and uniform. The fine-ground lithium slag powder is washed to remove impurities and dried at 60-80°C to normal humidity. The dried lithium slag powder is mixed with an alkaline activator (Na2CO3 or NaOH) and soaked. The amount of the alkaline activator added is 2-5% of the mass of the lithium slag, and the activation time is 24-48 hours. After complete reaction, the unreacted solid particles are removed by sieving to obtain the modified lithium slag powder.

[0045] The present application uses a combined treatment method of mechanical grinding and alkaline activation to significantly enhance the pozzolanic reactivity of lithium slag powder and improve the mechanical properties and ductility of ultra-high ductility lithium slag concrete. The above modification method provides a new way for large-scale resource utilization of lithium slag, effectively utilizes lithium slag, reduces the harm of lithium slag to nature, and alleviates the shortage and insufficient supply of other building materials, achieving the reuse of industrial waste.

[0046] The cement used in the preparation process of the examples and comparative examples is 42.5 ordinary portland cement, the particle size of quartz sand is 0.3-0.6 mm, the fineness modulus is 2.5-3.0, the length of polyethylene fiber is 18 mm, the diameter is 25 µm, and the aspect ratio is 720.

[0047] Example 1

[0048] S1, take cement 400 parts, modified lithium slag powder 80 parts, fly ash 600 parts, quartz sand 400 parts, polyethylene fiber 15 parts, water-absorbing polymer 35 parts, high-efficiency water reducing agent 4 parts, thickening agent 2 parts and water 350 parts by mass fraction.

[0049] S2, cement, modified lithium slag powder, quartz sand, fly ash and high efficiency water reducing agent are added into the mixer, and slowly stirred at 100-135 r / min for 3-5 min until mixed uniformly to obtain dry materials.

[0050] S3, water is added to the dry materials in S1, and slowly stirred for 2-3 min, then the thickening agent is added after the dry materials are liquefied, and stirred uniformly to obtain mixed materials.

[0051] S4, polyethylene fibers are slowly added to the mixed materials in S3, and stirred at 185-230 r / min for 2-3 min until the polyethylene fibers are uniformly dispersed to obtain slurry.

[0052] S5, the slurry in S4 is poured into a mold, and after vibration forming, it is sealed, demolded and cured at room temperature for 28 days to obtain super-high ductility lithium slag concrete.

[0053] Example 2

[0054] S1, cement 420 parts, modified lithium slag powder 100 parts, fly ash 650 parts, quartz sand 450 parts, polyethylene fiber 17 parts, water-absorbing polymer 30 parts, high efficiency water reducing agent 5 parts, thickening agent 3 parts and water 360 parts are weighed according to mass fraction.

[0055] S2, cement, modified lithium slag powder, quartz sand, fly ash and high efficiency water reducing agent are added into the mixer, and slowly stirred at 100-135 r / min for 3-5 min until mixed uniformly to obtain dry materials.

[0056] S3, water is added to the dry materials in S1, and slowly stirred for 2-3 min, then the thickening agent is added after the dry materials are liquefied, and stirred uniformly to obtain mixed materials.

[0057] S4, polyethylene fibers are slowly added to the mixed materials in S3, and stirred at 185-230 r / min for 2-3 min until the polyethylene fibers are uniformly dispersed to obtain slurry.

[0058] S5, the slurry in S4 is poured into a mold, and after vibration forming, it is sealed, demolded and cured at room temperature for 28 days to obtain super-high ductility lithium slag concrete.

[0059] Example 3

[0060] S1, cement 390 parts, modified lithium slag powder 60 parts, fly ash 550 parts, quartz sand 300 parts, polyethylene fiber 20 parts, water-absorbing polymer 40 parts, high efficiency water reducing agent 4.5 parts, thickening agent 2.5 parts and water 340 parts are weighed according to mass fraction.

[0061] S2, cement, modified lithium slag powder, quartz sand, fly ash and high efficiency water reducing agent are added into the mixer, and slowly stirred at 100-135 r / min for 3-5 min until mixed uniformly to obtain dry materials.

[0062] S3, continue to slowly stir for 2-3 min after adding water to the dry material in S1, add thickening agent after the dry material is liquefied, and uniformly stir to obtain a mixture.

[0063] S4, slowly add polyethylene fibers to the mixture in S3, and quickly stir at 185-230 r / min for 2-3 min until the polyethylene fibers are uniformly dispersed, to obtain a slurry.

[0064] S5, pour the slurry in S4 into a mold, seal after vibration forming, and maintain at room temperature for 28 days after demolding, to obtain super-high ductility lithium slag concrete.

[0065] Comparative Example 1

[0066] S1, take cement 500 parts, fly ash 600 parts, quartz sand 400 parts, polyethylene fibers 5 parts, water-absorbing polymer 35 parts, high-efficiency water reducing agent 4 parts, thickening agent 2 parts, and water 350 parts by mass fraction.

[0067] S2, add cement, quartz sand, fly ash, and high-efficiency water reducing agent into a mixer, and slowly stir at 100-135 r / min for 3-5 min until mixed uniformly, to obtain dry material.

[0068] S3, continue to slowly stir for 2-3 min after adding water to the dry material in S1, add thickening agent after the dry material is liquefied, and uniformly stir to obtain a mixture.

[0069] S4, slowly add polyethylene fibers to the mixture in S3, and quickly stir at 185-230 r / min for 2-3 min until the polyethylene fibers are uniformly dispersed, to obtain a slurry.

[0070] S5, pour the slurry in S4 into a mold, seal after vibration forming, and maintain at room temperature for 28 days after demolding, to obtain concrete.

[0071] Comparative Example 2

[0072] S1, take cement 420 parts, lithium slag powder 80 parts, fly ash 600 parts, quartz sand 400 parts, water-absorbing polymer 35 parts, high-efficiency water reducing agent 4 parts, thickening agent 2 parts, and water 340 parts by mass fraction.

[0073] S2, add cement, lithium slag powder, quartz sand, fly ash, and high-efficiency water reducing agent into a mixer, and slowly stir at 100-135 r / min for 3-5 min until mixed uniformly, to obtain dry material.

[0074] S3, continue to slowly stir for 2-3 min after adding water to the dry material in S1, add thickening agent after the dry material is liquefied, and uniformly stir to obtain a slurry.

[0075] S4, the slurry in S3 is cast into a mold, and after vibration forming, it is sealed, demolded, and cured at room temperature for 28 days to obtain concrete.

[0076] Comparative Example 3

[0077] S1, cement 420 parts by mass, lithium slag powder 80 parts, fly ash 600 parts, quartz sand 400 parts, polyethylene fiber 30 parts, water-absorbing polymer 35 parts, high-efficiency water reducing agent 4 parts, and water 340 parts are weighed.

[0078] S2, the cement, lithium slag powder, quartz sand, fly ash, and high-efficiency water reducing agent are added to a mixer, and slowly stirred at 100-135 r / min for 3-5 min until uniformly mixed to obtain dry materials.

[0079] S3, water is added to the dry materials in S2, and slow stirring is continued for 2-3 min, then the thickening agent is added after the dry materials are liquefied, and stirred uniformly to obtain a mixture.

[0080] S4, polyethylene fiber is slowly added to the mixture in S3, and stirred at 185-230 r / min for 2-3 min until the polyethylene fiber is uniformly dispersed to obtain a slurry.

[0081] S5, the slurry in S4 is cast into a mold, and after vibration forming, it is sealed, demolded, and cured at room temperature for 28 days to obtain concrete.

[0082] Test Example 1

[0083] The mechanical properties of the super-high ductility lithium slag concrete in Examples 1-3 and the concrete in Comparative Examples 1-3 are tested, and the results are shown in Table 1.

[0084] Table 1, mechanical property data table of Examples 1-3 and Comparative Examples 1-3

[0085]

[0086] As can be seen from Table 1, the super-high ductility lithium slag concrete in Example 1 has good deformation capacity, excellent steady-state cracking behavior and ductility. The super-high ductility lithium slag concrete in Example 2 shows good strain hardening characteristics and ductility, and the super-high ductility lithium slag concrete in Example 3 shows excellent tensile ductility and crack control ability.

[0087] The concrete in Comparative Example 1 has limited performance improvement, brittle fracture, poor ductility and crack resistance due to the absence of lithium slag powder and the addition of a small amount of polyethylene fiber. The concrete in Comparative Example 2 has a significantly lower performance than the inventive Examples 1-3 due to the absence of physical and chemical activation of the lithium slag powder and the absence of polyethylene fiber, brittle failure and no multiple crack formation. The concrete in Comparative Example 3 becomes too viscous during mixing and construction due to the excessive addition of polyethylene fiber, and the polyethylene fiber is not uniformly dispersed and cannot achieve stable cracking.

[0088] Therefore, the present application adopts the above-mentioned components of a super-high ductility lithium slag concrete and a preparation method thereof. By activating and optimizing the lithium slag content, combining the filling effect of fly ash and the humidity adjusting function of the water-absorbing polymer, and introducing polyethylene fiber to achieve the large deformation and multiple crack formation of lithium slag concrete, the super-high ductility lithium slag concrete obtained has high ductility and strain hardening characteristics. Not only does it realize the resource utilization of modified lithium slag powder and overcome the brittleness of lithium slag concrete, but it also has the advantages of being green, environmentally friendly, low-cost, high-performance, and suitable for various building and engineering application scenarios.

[0089] Finally, it should be noted that the above examples are only used to illustrate the technical solutions of the present application and not to limit it. Although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present application can still be modified or replaced by equivalents, and these modifications or replacements cannot make the modified technical solutions deviate from the spirit and scope of the technical solutions of the present application.

Claims

1. An ultra-high ductility lithium slag concrete, characterized by: The components, calculated by mass, include 390-450 parts of cement, 40-120 parts of modified lithium slag powder, 500-700 parts of fly ash, 300-500 parts of quartz sand, 10-20 parts of polyethylene fiber, 30-40 parts of water-absorbing polymer, 3-6 parts of high-efficiency water reducer, 1-3 parts of thickener and 330-460 parts of water; The length of polyethylene fibers is 12-24 mm and the diameter is 20-30 μm; The water-absorbing polymer is a polyacrylic acid-acrylamide type high molecular water-absorbing resin with a particle size of 150-620 μm; The preparation steps of modified lithium slag powder are as follows: the waste lithium slag generated in the lithium salt industrial production process is recovered and crushed, finely ground, washed and dried in sequence; the crushing is first coarsely crushed and then finely ground, the coarse crushing is carried out in a jaw crusher, and after coarse crushing, it is screened using a stone sand screen to remove particles larger than 5mm, and the particles suitable for subsequent treatment are retained for fine grinding, which is carried out in a rotary drum ball mill until a specific surface area of ​​1100-1200m 2 / kg of lithium slag powder, the finely ground lithium slag powder is sieved to remove incompletely finely ground particles to ensure that fine and uniform lithium slag powder is finally obtained, the finely ground lithium slag powder is washed to remove impurities, and dried to normal humidity at 60-80°C, the dried lithium slag powder is mixed with an alkaline activator Na2CO3 or NaOH and then soaked, the amount of the alkaline activator added is 2-5% of the mass of the lithium slag, the activation time is 24-48 hours, and after complete reaction, it is sieved to remove unreacted solid particles to obtain modified lithium slag powder.

2. The ultra-high ductility lithium slag concrete according to claim 1, characterized in that: The particle size of quartz sand is 0.2-0.6mm, the fineness modulus is 2.5-3.0, and the mud content is less than 1%.

3. The ultra-high ductility lithium slag concrete according to claim 1, characterized in that: The particle size of fly ash is 50-400μm and the specific surface area is 400-600m 2 / kg.

4. The ultra-high ductility lithium slag concrete according to claim 1, characterized in that: The thickener is cellulose ether, and the added amount of the thickener is 0.03-0.05% of the total mass of the ultra-high ductility lithium slag concrete.

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