A large-mixing solid waste anti-freezing concrete and a preparation method thereof

Abstract

The application relates to the technical field of concrete, in particular to a large-mixing-amount solid waste anti-freezing concrete and a preparation method thereof, which comprises the following steps: adding cement, fly ash, slag, desulfurization gypsum, mineral powder, fine aggregate and coarse aggregate into a stirrer, stirring for a period of time, then adding water and stirring until the mixture is uniform and consistent. The large-mixing-amount solid waste anti-freezing concrete uses less cement mixing amount, makes materials with volcanic ash activity such as fly ash, slag and desulfurization gypsum fully react, and with the increasing amount of mineral powder replacing fly ash, more compact C-(A)-S-H gel structures are formed in the cementitious material, the pore structure of the low-carbon concrete is optimized, and the anti-freezing performance of the low-carbon concrete is effectively enhanced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of concrete, in particular to a large-mixing-amount solid waste anti-freezing concrete and a preparation method thereof. BACKGROUND

[0002] Low-carbon concrete is a new type of environmentally friendly building material that reduces carbon emissions by reducing the amount of cement used or using alternative materials. The core is to replace traditional cement with industrial by-products (such as fly ash, slag) or new types of cementitious materials, thereby reducing carbon dioxide emissions during production. Compared with ordinary Portland cement concrete, low-carbon concrete has the advantages of low carbon, better durability, and resource recycling. Solid waste materials such as fly ash and slag can improve the frost resistance and chloride ion resistance of concrete. In addition, during the reaction process, the hydration heat is reduced, thereby reducing the risk of concrete cracking. Therefore, low-carbon concrete realizes better long-term performance with lower environmental cost, which is the core direction of green building materials.

[0003] Although existing concrete technology can incorporate some fly ash, slag and other solid waste, the mixing amount is generally less than 40% of the total amount of cementitious materials, and the single solid waste activity difference easily leads to insufficient concrete late strength. If the mixing amount is increased, the frost resistance will decrease significantly due to insufficient hydration reaction, pore structure degradation and other problems. In the Inner Mongolia region of China, under the severe cold climate, traditional solid waste concrete is prone to cracking and peeling after freeze-thaw cycles due to the developed capillary pore structure, which seriously restricts the regional application of solid waste building materials. Current research focuses on the synergistic effect of multiple solid wastes, such as using fly ash, slag and other materials to replace cement. There are many types of solid waste in the Inner Mongolia region, but in practical applications, they are mostly limited to simple compounding, lacking of multi-component grading optimization and reaction control, resulting in difficulty in coordinating the compressive strength and frost resistance when the mixing amount of solid waste is ≥60%. Developing concrete technology with large-mixing-amount solid waste utilization and frost resistance has become a key requirement to break the regional solid waste dilemma and promote the upgrading of green building materials. SUMMARY

[0004] In view of the defects of the prior art, the purpose of the present application is to provide a large-mixing-amount solid waste anti-freezing concrete and a preparation method thereof to solve the problems raised in the background art.

[0005] The technical problem solved by the present application adopts the following technical scheme:

[0006] The present application provides a large-mixing-amount solid waste anti-freezing concrete, which comprises the following components in parts by mass:

[0007]

[0008] Preferably, the fine aggregate is river sand, and the river sand passes through a 4.75mm square hole screen;

[0009] Preferably, the coarse aggregate is gravel, and the coarse aggregate meets the continuous grading requirement, with 4.75mm-9.5mm accounting for 42%, 9.5mm-13.2mm accounting for 28%, 13.2mm-16mm accounting for 16%, and 16mm-19mm accounting for 14%.

[0010] Preferably, the slag passes through a 0.3mm square hole screen, and the desulfurization gypsum passes through a 190 mesh screen.

[0011] Preferably, the fine aggregate is river sand, and the river sand is processed as follows: (1) water washing treatment: the river sand is washed by a high-pressure water gun, with a water pressure of not less than 0.5MPa, and the continuous washing time is not less than 30 minutes, so as to remove clay and organic matter attached to the surface of the river sand;

[0012] (2) drying treatment: the river sand after water washing is placed in a ventilated and dry environment, with the environmental temperature controlled to be 25-35℃ and the relative humidity controlled to be not more than 60%, and the river sand is dried until the water content is not more than 0.5%;

[0013] (3) screening treatment: the dried river sand passes through a 4.75mm square hole screen, and the particles with a particle size of not more than 4.75mm are reserved after screening, and the fineness modulus is controlled to be in the range of 2.3-2.6.

[0014] Preferably, the coarse aggregate is gravel, and the gravel used in the test should be water washed for 24 hours and then dried to obtain the standard gravel used in the test. The coarse aggregate meets the continuous grading requirement, with 4.75mm-9.5mm accounting for 42%, 9.5mm-13.2mm accounting for 28%, 13.2mm-16mm accounting for 16%, and 16mm-19mm accounting for 14%.

[0015] Preferably, the processing method of the slag and the desulfurization gypsum comprises the following steps:

[0016] (1) drying treatment: the slag and the desulfurization gypsum are respectively placed in an oven, and are dried at a constant temperature of 115±5℃ until the water content is not more than 0.3%, with the drying time being not less than 4 hours for the slag and not less than 2 hours for the desulfurization gypsum;

[0017] (2) screening treatment:

[0018] The dried slag passes through a 0.3mm square hole screen, and the particles with a particle size of not more than 0.3mm are reserved after screening, and the particle grading meets the requirement that the particles with a particle size of not more than 0.15mm account for not more than 20%, and the particles with a particle size of 0.15-0.3mm account for not less than 80%. The desulfurization gypsum passes through a 190 mesh standard screen (with a pore size of about 0.075mm), and the particles with a particle size of not more than 0.075mm are reserved after screening, and the specific surface area is not less than 450m 2 / kg.

[0019] The anti-freezing concrete further comprises 5-8 parts of an adjusting agent, and the adjusting agent is prepared by the following specific method:

[0020] S1: heat-treating boron nitride at 155-160 DEG C for 1h, then increasing the temperature to 220 DEG C at a rate of 2-5 DEG C / min, keeping for 20 min, and then air cooling to room temperature to obtain heat-treated boron nitride;

[0021] S2: uniformly blending wood cellulose, calcium sulfate whisker, silicon carbide fiber, and sodium dodecyl benzene sulfonate solution according to a weight ratio of (3-5):(2-3):(5-7):13 to obtain wood cellulose solution;

[0022] Sufficiently blending 2-3 parts of bismuth titanate, 1-2 parts of lanthanum oxide, and 3-5 parts of sodium silicate to obtain an additive;

[0023] S3: stirring and treating the heat-treated boron nitride and wood cellulose solution according to a weight ratio of 3:5, and obtaining wood fiber-regulated boron nitride agent after stirring;

[0024] Sufficiently ball-milling the wood fiber-regulated boron nitride agent and the additive according to a weight ratio of 7:5, and obtaining a regulating agent after ball-milling, filtration, and drying; the mass fraction of the sodium dodecyl benzene sulfonate solution is 5-8%; the stirring speed of the stirring treatment is 550-750 r / min, and the stirring time is 1h; the ball-milling speed of the sufficient ball-milling is 1000-1500 r / min, and the ball-milling time is 2h.

[0025] The regulating agent is prepared by heat-treating boron nitride, stirring and treating the heat-treated boron nitride and wood cellulose solution, ball-milling the wood fiber-regulated boron nitride agent and the additive, improving the coordination of raw materials, and mutually regulating and coordinating the performance of the regulating agent to further enhance the performance coordination and stability of the regulating agent in the system.

[0026] The application also provides a preparation method of the large-mixing-amount solid waste anti-freezing concrete.

[0027] S: adding cement, fly ash, slag, desulfurization gypsum, mineral powder, fine aggregate, coarse aggregate, and the regulating agent into a stirrer, stirring for a period of time, then adding water and stirring until the mixture is uniform.

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

[0029] The large-mix solid waste anti-freezing concrete in the application adopts less cement content, so that materials with volcanic ash activity such as fly ash, slag, desulfurization gypsum and slag can fully react, and as the amount of slag replacing fly ash continuously increases, more compact C-(A)-S-H gel structure is formed in the cementitious material, so that the pore structure of the low-carbon concrete is optimized, the anti-freezing performance of the low-carbon concrete is effectively enhanced, especially in extreme cold environments, the generation and expansion of cracks are effectively delayed, and the long-term service performance of the material is improved. DETAILED DESCRIPTION

[0030] The technical solutions in the embodiments of the application will be clearly and completely described below in combination with specific embodiments. Obviously, the described embodiments are only part of the embodiments of the application, rather than all the embodiments. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative work fall within the protection scope of the application.

[0031] Embodiment 1: A large-mix solid waste anti-freezing concrete is prepared by mixing the following raw materials in parts by weight: cement 165 kg / m 3 , fly ash 231 kg / m 3 , slag 82.5 kg / m 3 , desulfurization gypsum 16.5 kg / m 3 , slag powder 55 kg / m 3 , water 143 kg / m 3 , fine aggregate 725 kg / m 3 , coarse aggregate 1000 kg / m 3 and adjusting agent 5 kg / m 3 .

[0032] Embodiment 2: A large-mix solid waste anti-freezing concrete is prepared by mixing the following raw materials in parts by weight: cement 165 kg / m 3 , fly ash 203.5 kg / m 3 , slag 82.5 kg / m 3 , desulfurization gypsum 16.5 kg / m 3 , slag powder 82.5 kg / m 3 , water 143 kg / m 3 , fine aggregate 725 kg / m 3 , coarse aggregate 1000 kg / m 3 and adjusting agent 8 kg / m 3 .

[0033] Embodiment 3: A large-mix solid waste anti-freezing concrete is prepared by mixing the following raw materials in parts by weight: cement 165 kg / m 3 , fly ash 176 kg / m 3, slag 82.5 kg / m 3 , desulfurization gypsum 16.5 kg / m 3 , mineral powder 110 kg / m 3 , water 143 kg / m 3 , fine aggregate 725 kg / m 3 , coarse aggregate 1000 kg / m 3 and regulator 7.5 kg / m 3 .

[0034] Comparative Example: A large amount of solid waste frost-resistant concrete was prepared by mixing the following raw materials in parts by weight: cement 165 kg / m 3 , fly ash 286 kg / m 3 , slag 82.5 kg / m 3 , desulfurization gypsum 16.5 kg / m 3 , mineral powder 0 kg / m 3 , water 143 kg / m 3 , fine aggregate 725 kg / m 3 , coarse aggregate 1000 kg / m 3 and regulator 5.5 kg / m 3 .

[0035] The fine aggregate, coarse aggregate, slag and desulfurization gypsum in the above Examples 1-3 and Comparative Example were treated by the following steps:

[0036] The fine aggregate was river sand, and the river sand was treated as follows: (1) water washing treatment: the river sand was washed with a high-pressure water gun, the water pressure was not less than 0.5 MPa, and the continuous washing time was ≥30 minutes to remove clay and organic matter attached to the surface;

[0037] (2) drying treatment: the washed river sand was placed in a ventilated and dry environment, the environmental temperature was controlled at 30°C, and the relative humidity was ≤60%, and the river sand was dried to a water content of ≤0.5%;

[0038] (3) screening treatment: the dried river sand was screened through a 4.75 mm square hole screen, and the particles with a particle size ≤4.75 mm were retained after screening, and the fineness modulus was controlled within the range of 2.45.

[0039] The coarse aggregate was crushed stone, and the crushed stone used in the test should be water washed for 24 hours first, and then dried to obtain the standard crushed stone used in the test. The coarse aggregate met the requirements of continuous grading, with 6 mm accounting for 42%, 10 mm accounting for 28%, 15 mm accounting for 16%, and 17 mm accounting for 14%.

[0040] The treatment method of the slag and desulfurization gypsum included the following steps:

[0041] (1) drying treatment: the slag and desulfurization gypsum are respectively placed in an oven, and dried at a constant temperature of 115±5℃ until the water content is ≤0.3%, and the drying time is ≥4 hours for the slag and ≥2 hours for the desulfurization gypsum;

[0042] (2) screening treatment:

[0043] The dried slag is screened through a 0.3mm square hole screen, and the particles with a particle size ≤0.3mm are retained after screening, and the particle size distribution meets: the proportion of particles with a particle size ≤0.15mm is ≤20%, and the proportion of 0.20mm particles is ≥80%; the desulfurization gypsum is screened through a 190 mesh standard screen (pore size about 0.075mm), and the particles with a particle size ≤0.075mm are retained after screening, and the specific surface area is ≥450m 2 / kg.

[0044] The specific preparation method of the adjusting agent is:

[0045] S1: heat-treating boron nitride at 158℃ for 1h, then increasing the temperature to 220℃ at a rate of 3.5℃ / min, keeping for 20min, and then air cooling to room temperature to obtain heat-treated boron nitride;

[0046] S2: uniformly blending wood cellulose, calcium sulfate whiskers, and silicon carbide fibers and a sodium dodecylbenzenesulfonate solution according to a weight ratio of 4:2.5:6:13 to obtain a wood cellulose liquid;

[0047] Sufficiently blending 2.5 parts of bismuth titanate, 1.5 parts of lanthanum oxide, and 4 parts of sodium silicate to obtain an additive;

[0048] S3: stirring the heat-treated boron nitride and the wood cellulose liquid according to a weight ratio of 3:5, and obtaining a wood fiber-regulated boron nitride agent after stirring;

[0049] Sufficiently ball-milling the wood fiber-regulated boron nitride agent and the additive according to a weight ratio of 7:5, and obtaining an adjusting agent after ball-milling, filtration, and drying; the mass fraction of the sodium dodecylbenzenesulfonate solution is 6.5%; the stirring speed of the stirring treatment is 600r / min, and the stirring time is 1h; the ball-milling speed of the sufficient ball-milling is 1250r / min, and the ball-milling time is 2h.

[0050] The low-carbon concrete ratio table in the above examples 1-3 and comparative examples is as follows:

[0051]

[0052] The above raw materials are prepared into low-carbon concrete according to the ratio, which includes the following steps:

[0053] The cement, fly ash, slag, desulfurization gypsum, mineral powder and aggregate dry mixing agent are mixed uniformly, stirred for 1 min, and then water is added to fully stir until the mixture is uniform.

[0054] In the table, the coarse aggregate is gravel, and the fine aggregate is river sand. The river sand needs to pass through a 4.75 mm square hole screen. The coarse aggregate meets the requirements of continuous grading, with a proportion of 42% for 4.75 mm-9.5 mm, 28% for 9.5 mm-13.2 mm, 16% for 13.2 mm-16 mm, and 14% for 16 mm-19 mm. The slag in the cementitious material should pass through a 0.3 mm square hole screen, and the desulfurization gypsum should pass through a 190 mesh screen.

[0055] The concrete prepared in Examples 1-3 and the comparative example is poured into a pre-prepared mold, ensuring uniform filling, and vibrated on a vibration table to remove air bubbles and ensure internal compactness. A spatula is used to scrape the mixture on the surface of the mold to ensure a smooth and flat surface of the test piece, which is demolded after 1 day. The demolded concrete test piece is carefully transferred to a curing room and placed on a suitable support to ensure that the test piece is not subjected to uneven forces. During the curing process, the temperature and humidity in the curing room are regularly checked to ensure that they meet the set standard curing conditions. The curing temperature is 21-23°C, and the humidity is 95-97°C.

[0056] The test pieces obtained in Examples 1-3 and the comparative example are subjected to water freezing and mass loss rate, dynamic elastic modulus, and compressive strength analysis tests:

[0057] Through the mass loss rate data, it is found that in the water freezing test, the mass loss rate of all mix proportions gradually increases with the increase in the number of freeze-thaw cycles.

[0058] The comparative example K0 (without mineral powder content) has the most significant increase in mass loss rate, with a mass loss rate of 5.23% after 250 freeze-thaw cycles, indicating that low-carbon concrete without mineral powder has the worst frost resistance, with more serious surface spalling.

[0059] In contrast, as the mineral powder content increases (K10, K15, K20), the mass loss rate shows a decreasing trend first and then an increasing trend. K10 has a mass loss rate of 5.19% after 300 freeze-thaw cycles, and K15 has a mass loss rate of 4.94% after 300 freeze-thaw cycles. In contrast, K20 has a mass loss rate of 5.46% after 275 freeze-thaw cycles, with an increase in mass loss rate and only 275 freeze-thaw cycles. Compared with K0, it only increases by 25 times, and compared with K10, it decreases by 25 times, showing poor frost resistance. This indicates that a higher mineral powder content weakens the frost resistance of low-carbon concrete, and the surface spalling is more serious.

[0060] Secondly, through the data of dynamic elastic modulus, it can be known that in the freeze-thaw test, the mix proportions with different mineral powder contents show the trend that the dynamic elastic modulus decreases with the increase of freeze-thaw cycle number. The dynamic elastic modulus of the mix proportion K0 (0% mineral powder) decreases from the initial about 38.1 x 10 3 MPa to about 15.4 x 10 3 MPa, losing about 59.6% of the dynamic elastic modulus. The dynamic elastic modulus of the mix proportion K10 (10% mineral powder) decreases from the initial about 41.6 x 10 3 MPa to about 20.9 x 10 3 MPa, losing about 49.8% of the dynamic elastic modulus. It can be found that the appropriate addition of mineral powder can reduce the loss of dynamic elastic modulus. The dynamic elastic modulus of the mix proportion K15 (15% mineral powder) decreases from about 41.8 x 10 3 MPa to about 21.6 x 10 3 MPa, decreasing by about 48.3%. The dynamic elastic modulus of the mix proportion K20 (20% mineral powder) decreases from about 43.8 x 10 3 MPa to about 22.9 x 10 3 MPa, decreasing by about 47.7%. The core mechanism lies in the synergistic effect of CaO≥35% in the mineral powder and SiO2+Al2O3≥80% in the fly ash, combined with the particle size distribution filling of the mineral powder (D50≤15 μm) and the fly ash (D50≤5 μm), so as to reduce the porosity of the cementitious material and significantly delay the freeze-thaw damage. However, since the mass loss rate of the mix proportion has exceeded 5%, it indicates that the freeze-thaw cycle has ended, so it also shows that with the increase of the mineral powder content, the frost resistance increases first and then decreases.

[0061] Through the test data of the compressive strength in the whole freeze-thaw cycle process, it can be known that in the freeze-thaw test, the mix proportions with different mineral powder contents show the trend that the compressive strength decreases with the increase of freeze-thaw cycle number. The compressive strength of the mix proportion K0 (0 kg / m 3 ) decreases from the initial about 23.4 MPa to about 5.7 x 10 3 MPa, and when the freeze-thaw cycle proceeds to 175 times, the compressive strength of the concrete test piece cannot be measured, indicating that the bearing capacity of the low-carbon concrete without mineral powder has been lost with the proceeding of the freeze-thaw cycle. The compressive strength of the mix proportion K10 (55 kg / m 3 ) decreases from the initial about 45.7 MPa to 4.7 MPa at the freeze-thaw cycle of 250 times. It can be found that the appropriate addition of mineral powder can increase the compressive strength of the low-carbon concrete and the bearing capacity after the freeze-thaw cycle. The compressive strength of the mix proportion K15 (82.5 kg / m 3 ) decreases from the initial 61.2 MPa to 6.8 MPa at the freeze-thaw cycle of 300 times. The compressive strength of the mix proportion K20 (110 kg / m 3) from the initial 56.5 MPa to 4.2 MPa after 250 freeze-thaw cycles. It can be seen that although the initial compressive strength of K20 is higher, the bearing capacity of the concrete decreases more obviously under the influence of freeze-thaw environment, and the bearing capacity of the concrete of K15 remains good, which also shows that with the increase of the content of mineral powder, the bearing capacity of low-carbon concrete in the freeze-thaw cycle process increases first and then decreases, that is, the frost resistance of the concrete increases first and then decreases.

[0062] In general, with the continuous increase of the content of mineral powder, the mass loss, dynamic elastic modulus and compressive strength change of low-carbon concrete in the freeze-thaw cycle process all meet the first decrease and then increase, that is, the frost resistance increases first and then decreases. In summary, the frost resistance of K15 is the strongest.

[0063] It is apparent for those skilled in the art that the present application is not limited to the details of the above exemplary embodiments, but can be implemented in other concrete forms without departing from the spirit or essential characteristics of the present application. Therefore, the embodiments should be considered in all respects as illustrative and not restrictive, the scope of the present application being indicated by the appended claims rather than by the above description, and it is intended to embrace all changes and modifications that fall within the meaning and scope of equivalents of the claims.

[0064] Furthermore, it should be understood that although the present specification is described in terms of embodiments, not every embodiment contains only one independent technical solution, and the description of the specification is only for the sake of clarity, and those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can be properly combined to form other embodiments that those skilled in the art can understand.

Claims

1. A high-volume solid waste freeze-resistant concrete, characterized by, By mass fraction, it comprises the following components: Cement: 165 parts Fly ash: 176-286 parts Slag: 82.5 parts Desulfurization gypsum: 16.5 parts Mineral powder: 55-110 parts Water: 143 parts Fine aggregate: 725 parts Coarse aggregate: 1000 parts The anti-freezing concrete further comprises 5-8 parts of the adjusting agent, and the adjusting agent is prepared by the following steps: S1: heat-treating boron nitride at 155-160℃ for 1h, then heating to 220℃ at a rate of 2-5℃ / min, keeping for 20min, and then air cooling to room temperature to obtain heat-treated boron nitride; S2: blending wood cellulose, calcium sulfate whisker, silicon carbide fiber and sodium dodecyl benzene sulfonate solution according to a weight ratio of (3-5):(2-3):(5-7):13 to obtain wood cellulose solution; S3: blending bismuth titanate 2-3 parts, lanthanum oxide 1-2 parts and sodium silicate 3-5 parts to obtain an additive; S4: stirring the heat-treated boron nitride and the wood cellulose solution according to a weight ratio of 3:5 to obtain wood fiber-regulated boron nitride agent; S5: ball-milling the wood fiber-regulated boron nitride agent and the additive according to a weight ratio of 7:5 to obtain the adjusting agent.

2. The freeze-resistant concrete with high volume of solid waste according to claim 1, characterized in that, The fine aggregate is river sand, and the river sand is treated by the following steps: (1) water washing treatment: washing the river sand by using a high-pressure water gun, the water pressure is not less than 0.5MPa, and the continuous washing time is ≥30min to remove clay and organic matter attached to the surface of the river sand; (2) air-drying treatment: placing the water-washed river sand in a ventilated and dry environment, controlling the environmental temperature to be 25-35℃ and the relative humidity to be ≤60%, and air-drying the river sand until the water content is ≤0.5%; (3) screening treatment: screening the air-dried river sand by using a 4.75mm square hole screen, and retaining the particles with a particle size ≤4.75mm after the screening, and controlling the fineness modulus to be in the range of 2.3-2.

6.

3. The freeze-resistant concrete with high volume of solid waste according to claim 1, characterized in that, The treatment method of the slag and the desulfurization gypsum comprises the following steps: (1) drying treatment: placing the slag and the desulfurization gypsum in an oven respectively, drying them at a constant temperature of 115±5℃ until the water content is ≤0.3%, and the drying time is ≥4h for the slag and ≥2h for the desulfurization gypsum; (2) screening treatment: screening the dried slag by using a 0.3mm square hole screen, and retaining the particles with a particle size ≤0.3mm after the screening, and the particle grading meets the requirements that the particles with a particle size ≤0.15mm account for ≤20%, and the particles with a particle size of 0.15-0.3mm account for ≥80%; screening the desulfurization gypsum by using a 190-mesh standard screen (the aperture is about 0.075mm), and retaining the particles with a particle size ≤0.075mm after the screening, and the specific surface area is ≥450 m² / kg.

4. The freeze-resistant concrete with high volume of solid waste according to claim 1, characterized in that, The coarse aggregate is gravel, and the gravel used in the test should be water-washed for 24h, and then dried to obtain the standard gravel used in the test. The coarse aggregate meets the requirements of continuous grading, and the proportion of the particles with a particle size of 4.75mm-9.5mm is 42%, the proportion of the particles with a particle size of 9.5mm-13.2mm is 28%, the proportion of the particles with a particle size of 13.2mm-16mm is 16%, and the proportion of the particles with a particle size of 16mm-19mm is 14%.

5. The freeze-resistant concrete of claim 1, wherein, The mass fraction of the sodium dodecyl benzene sulfonate solution is 5-8%.

6. The freeze-resistant concrete of claim 1, wherein, The stirring speed of the stirring treatment is 550-750 r / min, and the stirring time is 1 h; the ball milling speed of the blending ball milling is 1000-1500 r / min, and the ball milling time is 2 h.

7. The method of producing the frost-resistant concrete with a large amount of solid waste according to claim 1, characterized in that, The method comprises the following steps: S: cement, fly ash, slag, desulfurization gypsum, mineral powder, fine aggregate and coarse aggregate and adjusting agent are added into a stirrer, and stirring is carried out for a period of time, then water is added and stirring is carried out until the mixture is uniform and consistent.

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