A multi-solid waste-based chlorine salt corrosion-resistant geopolymer concrete material and a preparation method thereof

Abstract

The present application relates to the field of geopolymer materials, and particularly relates to a multi-solid waste-based chlorine salt corrosion resistant geopolymer concrete material and a preparation method thereof. The chlorine salt corrosion resistant geopolymer is composed of solid powder, aggregate and alkali activator; wherein the solid powder is composed of fly ash and slag, the aggregate is iron tailings and fine sand, and the alkali activator is prepared by mixing solid sodium hydroxide, carbide slag, water glass and water. The present application takes fly ash, slag, iron tailings and fine sand as main raw materials, and a new type of chlorine salt corrosion resistant concrete material is obtained by mixing with the alkali activator; the process is simple, has no CO2 emission, has good mechanical properties, can meet the general marine concrete building use requirements, and also realizes the resource utilization of fly ash and blast furnace ironmaking slag, can effectively solve the environmental pollution problem caused by fly ash and slag storage, and has good application prospect.

Description

Technical Field

[0001] This invention relates to the field of geopolymer materials, specifically to a multi-solid waste-based chloride-resistant geopolymer concrete material and its preparation method. Background Technology

[0002] In marine environments, most marine concrete structures corrode and fail before reaching their designed service life, posing serious safety hazards to national marine engineering projects and causing marine environmental pollution. Chloride ion-induced steel reinforcement corrosion is the main cause of the deterioration of marine concrete structural performance. Port facilities are generally designed for a service life of 50-100 years, but in reality, steel reinforcement may corrode after only about 20 years of use. This not only causes severe economic losses to the country but also poses significant safety risks to marine engineering projects. Therefore, adopting effective methods to resist chloride ion corrosion and extend the service life of concrete is essential for the sustainable development of the marine economy. Geopolymers have received widespread attention in building materials due to their early strength, rapid hardening, and corrosion resistance, and are expected to replace ordinary cement. Furthermore, the sustainable and environmentally friendly characteristics of geopolymers play an important role in solid waste treatment.

[0003] The rapid development of modern society has led to an ever-increasing demand for coal and steel. The production of these two materials inevitably generates large quantities of fly ash, blast furnace slag, and iron tailings, which are major components of my country's bulk industrial solid waste. However, the current practice of stockpiling fly ash, slag, and iron tailings has resulted in land occupation and environmental pollution. Therefore, the comprehensive utilization of fly ash and slag has become an important trend in the treatment of bulk industrial solid waste.

[0004] Geopolymers, derived from one or more silicoaluminoid raw materials and induced by alkaline activators, are inorganic cementitious materials with a three-dimensional network structure composed of [SiO4] tetrahedral and [AlO4] tetrahedral structural units. They possess advantages such as low energy consumption, simple preparation process, low CO2 emissions, high strength, and good durability. Fly ash, slag, and iron tailings are widely available sources; using them as raw materials to prepare geopolymers can not only treat industrial solid waste but also serve as building materials in chloride-rich environments. Currently, research on using solid waste as geopolymer-resistant chloride-corrosion-resistant concrete materials is limited. Therefore, studying the preparation of chloride-corrosion-resistant geopolymer concrete materials from fly ash, slag, and iron tailings, and their preparation methods, has significant environmental and ecological implications for the comprehensive utilization of solid waste. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of existing technologies and provide a multi-solid waste-based chloride-resistant geopolymer concrete material and its preparation method. This chloride-resistant geopolymer is composed of solid powder, aggregate, and an alkali activator. The solid powder consists of fly ash and blast furnace slag, the aggregate is iron tailings and fine sand, and the alkali activator is a mixture of solid sodium hydroxide, carbide slag, water glass, and water. This invention uses fly ash, blast furnace slag, iron tailings, and fine sand as main raw materials, and through mixing with an alkali activator, obtains a novel chloride-resistant concrete material. Its process is simple, produces no CO2 emissions, and possesses good mechanical properties, meeting the requirements of general marine engineering concrete construction. It also achieves the resource utilization of fly ash and blast furnace slag, effectively solving the environmental pollution problems caused by fly ash and slag storage, and has good application prospects.

[0006] To achieve the above objectives, the technical solution of the present invention is as follows:

[0007] A multi-solid waste-based chloride salt corrosion resistant geopolymer concrete material, comprising the following raw materials:

[0008] Solid powders, aggregates, and alkali activators:

[0009] The solid powder consists of 10wt% to 50wt% fly ash and 50wt% to 90wt% slag.

[0010] Furthermore, based on a total weight percentage of 100%, the mass percentages of each component in the fly ash are as follows: SiO2 50%–60%, Al2O3 25%–30%, Fe2O3 10%–20%, CaO 0.01%–0.05%, MgO 0.01%–0.08%, K2O 1%–3%, Na2O 0.01%–0.03%, TiO2 1%–3%, and its loss on ignition is 0.5%–1%.

[0011] Furthermore, based on a total weight percentage of 100%, the mass percentages of each component in the slag are as follows: SiO2 25%–40%, Al2O3 5%–20%, Fe2O3 0.1%–1%, CaO 30%–50%, MgO 1%–3%, TiO2 1%–2%, Na2O 0.1%–1%, K2O 0.1%–0.5%, and its loss on ignition is 1%–5%.

[0012] The aggregate consists of iron tailings and fine sand, with a total amount of 2 to 2.5 times the mass of solid powder. The amount of iron tailings added is 20 wt% to 60 wt%, and the amount of fine sand added is 40 wt% to 80 wt%, with a total mass fraction of 100 wt%.

[0013] Furthermore, based on a total weight percentage of 100%, the mass percentages of each component in the iron tailings are as follows: SiO2 30%–50%, Al2O3 10%–20%, Fe2O3 20%–30%, CaO 5%–10%, MgO 1%–3%, K2O 1%–3%, Na2O 1%–3%, TiO2 1%–2%, MnO 0.1%–0.5%, and its loss on ignition is 0.4%–1%.

[0014] Furthermore, based on a total weight percentage of 100%, the mass percentages of each component in the fine sand are as follows: SiO2 80%–90%, Al2O3 5%–10%, Na2O 0.1%–0.5%, K2O 1%–5%, Fe2O3 1%–5%, and its loss on ignition is 0.5%–1%.

[0015] The alkaline activator is a mixture of sodium hydroxide, carbide slag, water glass, and water. The amount of water glass is 30% to 45% of the mass of the solid powder, the amount of carbide slag is 1% to 5% of the mass of the solid powder, the amount of solid sodium hydroxide is 7.5% to 11% of the mass of the solid powder, and the mass ratio of water to solid powder is 0.6 to 0.65.

[0016] Furthermore, the particle size of the fly ash and slag is less than 0.075 mm, and the particle size of the fine sand and iron tailings is less than 0.5 mm.

[0017] Furthermore, the solution modulus of the alkali activator is 0.8 to 1.5; the modulus of the water glass is 3.3, the solid content is 34%, and the Baumé degree is 40.

[0018] A method for preparing a multi-solid waste-based chloride salt corrosion-resistant geopolymer concrete material specifically includes the following steps:

[0019] Step S1: Mix fly ash, slag, iron tailings and fine sand evenly in proportion to obtain solid mixture A;

[0020] Step S2: Dissolve solid sodium hydroxide and carbide slag in water, add water glass, stir and mix well, and let stand for 2 hours to obtain an alkaline activator;

[0021] Step S3: Mix the solid powder A obtained in step S1 with the alkali activator obtained in step S2, and then mechanically stir to obtain a mixed slurry B;

[0022] Step S4: Pour the mixed slurry B into the steel mold and the columnar mold with embedded steel bars, and continuously vibrate to remove air from the slurry;

[0023] Step S5: Seal the sample together with the mold, cure it at a certain curing temperature and time, and cure it at room temperature after demolding.

[0024] Furthermore, the mechanical stirring time in step S3 is 4-8 minutes.

[0025] Furthermore, in step S5, the curing temperature is 60–90°C, and the curing time is 6–12 hours; the curing time at room temperature is 14–28 days.

[0026] This invention primarily utilizes three raw materials—fly ash, slag, and iron tailings—to provide active silica-alumina compounds. The alkali activator consists of solid sodium hydroxide, carbide slag, water glass, and water. Under high-alkali conditions, the active silica-alumina compound components in the fly ash, slag, and iron tailings undergo depolymerization followed by repolymerization, ultimately cross-linking to form a three-dimensional network structure. The synergistic effect of fly ash, slag, iron tailings, and solid sodium hydroxide, carbide slag, and water glass significantly reduces the internal pore size, resulting in a denser structure and significantly improved mechanical properties of the geopolymer. Simultaneously, chloride ions readily combine chemically to form Friedel's salts in a high-calcium, high-aluminum environment and are easily physically adsorbed within the three-dimensional network structure, hindering chloride ion corrosion and enhancing the geopolymer's resistance to chloride salt corrosion.

[0027] The beneficial effects of this invention are as follows:

[0028] 1) This invention uses industrial solid waste to prepare chloride-resistant geopolymer concrete materials. The raw materials are widely available, the preparation process is simple, green and environmentally friendly, and the production cost is low. It effectively solves the problems of tailings accumulation and environmental pollution, and is conducive to the high-value utilization of industrial solid waste.

[0029] 2) The chloride-resistant geopolymer concrete prepared by this invention has high compressive strength, meets the strength grade requirements of GB175-2007 "General Portland Cement" P42.5R, meets the needs of general marine engineering construction materials, and can be used as marine concrete material.

[0030] 3) Unlike traditional silicate cement concrete, the geopolymer concrete prepared by this invention has a denser structure and a higher degree of polymerization. At room temperature, immersion in a 3.5% sodium chloride solution with a 1.5V voltage accelerated the corrosion of the reinforcing steel. Electrochemical monitoring was performed on the samples every 12 hours of acceleration, for a total of 240 hours. The results showed that the geopolymer concrete exhibited significant resistance to chloride corrosion. Microscopic testing of the chloride-corroded concrete revealed that its unique three-dimensional network structure and high calcium and aluminum content physically adsorbed and chemically bound chloride ions, further hindering their entry. Attached Figure Description

[0031] Figure 1 The image shows the XRD pattern of the fly ash used in the embodiments of the present invention.

[0032] Figure 2 The image shows the XRD pattern of the slag used in the embodiments of this application.

[0033] Figure 3 The image shows an XRD pattern of a sample from one of the embodiments of this application. Detailed Implementation

[0034] The optimized embodiments of the present invention will now be described in more detail. While optimized embodiments of the present invention are described below, it should be understood that the present invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to make the present invention more thorough and complete, and to fully convey the scope of the present invention to those skilled in the art. The scope of protection of the present invention includes, but is not limited to, the following:

[0035] The mass percentages of each component in the fly ash used in the following examples are as follows: SiO2 53.08%, Al2O3 28.64%, Fe2O3 13.24%, TiO2 2.39%, K2O 1.58%, MnO 0.10%, CaO 0.04%, MgO 0.03%;

[0036] The mass percentages of each component in the slag used in the following examples are as follows: SiO2 29.16%, CaO 42.35%, Al2O3 14.60%, TiO2 1.36%, MgO 7.76%, Na2O 0.46%, K2O 0.40%, Fe2O3 0.50%;

[0037] The mass percentages of each component in the iron tailings used in the following examples are as follows: SiO2 45.07%, Al2O3 13.38%, Fe2O3 25.75%, CaO 6.91%, MgO 2.47%, K2O 2.42%, Na2O 2.03%, TiO2 1.75%, MnO 0.22%;

[0038] The mass percentages of each component in the fine sand used in the following examples are as follows: SiO2 84.53%, Al2O3 7.62%, Na2O 0.44%, K2O 3.25%, Fe2O3 1.04%.

[0039] The calcium carbide slag used in the following examples is the waste residue produced from the production of acetylene from calcium carbide. The solid sodium hydroxide and water glass are commercially available chemical reagents. The water glass has a modulus of 3.3, a Na2SiO3 content of 34%, a Baumé degree of 40, and contains 26.5 wt% SiO2 and 8.3 wt% Na2O.

[0040] The water used in the following examples is free water.

[0041] Example 1:

[0042] The chloride-resistant geopolymer concrete material of this embodiment includes solid powder, aggregate, and alkali activator; the solid powder contains 10 wt% fly ash and 90 wt% slag; the aggregate contains 20 wt% iron tailings and 80 wt% fine sand. The alkali activator contains 30 wt% water glass, 7.5 wt% solid sodium hydroxide, and 1 wt% calcium carbide slag; the water-to-solid ratio is 0.6; and the solution modulus of the alkali activator is 1.

[0043] In preparation, 30g of fly ash and 270g of slag are weighed and mixed evenly to obtain solid powder. 120g of iron tailings and 480g of fine sand are weighed and mixed evenly to obtain aggregate. The aggregate and solid powder are mixed evenly to obtain solid mixture A. 3g of calcium carbide slag is weighed and dissolved in 50g of water. 22.5g of sodium hydroxide is weighed and dissolved in 71.32g of water. After the sodium hydroxide solution is clarified, 90g of water glass is added, stirred evenly, and allowed to stand for 24 hours. The settled sodium hydroxide and water glass mixture is poured into the calcium carbide slag solution to obtain an alkali activator. Solid mixture A is mixed with the alkali activator and stirred for 5 minutes to obtain mixture slurry B. This slurry is poured into a 30mm×30mm×30mm steel mold containing reinforcing bars. The slurry was poured into a cylindrical mold and continuously vibrated to expel air. The sample was sealed together with the mold and cured in an oven at 60°C for 6 hours. After demolding, it was cured at room temperature for 14 days.

[0044] The cured cubic specimens were used for compressive strength testing, and the cured cylindrical specimens with embedded steel bars were used for chloride salt resistance testing. The compressive strength test was carried out for 14 days on an integrated compression and flexural strength testing machine. The part of the cylindrical specimen with embedded steel bars exposed to air was sealed, and the rest was completely immersed in a 3.5wt% sodium chloride solution. A voltage of 1.5V was applied to accelerate corrosion. Electrochemical monitoring was carried out every 12 hours of acceleration, for a total of 240 hours. The steel bars began to corrode after 204 hours.

[0045] Example 2:

[0046] The chloride-resistant geopolymer concrete material of this embodiment includes solid powder, aggregate, and alkali activator; the solid powder contains 10% wt fly ash and 90 wt% slag; the aggregate contains 60 wt% iron tailings and 40 wt% fine sand. The alkali activator contains 30 wt% water glass, 7.5 wt% solid sodium hydroxide, and 1 wt% calcium carbide slag; the water-to-solid ratio is 0.6; and the solution modulus of the alkali activator is 1.

[0047] In preparation, 30g of fly ash and 270g of slag are weighed and mixed evenly to obtain solid powder. 360g of iron tailings and 240g of fine sand are weighed and mixed evenly to obtain aggregate. The aggregate and solid powder are mixed evenly to obtain solid mixture A. 3g of calcium carbide slag is weighed and dissolved in 50g of water. 22.5g of sodium hydroxide is weighed and dissolved in 71.32g of water. After the sodium hydroxide solution is clarified, 90g of water glass is added, stirred evenly, and allowed to stand for 24 hours. The settled sodium hydroxide and water glass mixture is poured into the calcium carbide slag solution to obtain an alkali activator. The solid mixture A is mixed with the alkali activator and stirred for 5 minutes to obtain a slurry B, which is poured into a 30mm×30mm×30mm steel mold containing reinforcing bars. The slurry was poured into a cylindrical mold and continuously vibrated to expel air. The sample was sealed together with the mold and cured in an oven at 60°C for 6 hours. After demolding, it was cured at room temperature for 14 days.

[0048] The cured cubic specimens were used for compressive strength testing, and the cured cylindrical specimens with embedded steel bars were used for chloride salt resistance testing. The compressive strength test was carried out for 14 days on an integrated compression and flexural strength testing machine. The part of the cylindrical specimen with embedded steel bars exposed to air was sealed, and the rest was completely immersed in a 3.5wt% sodium chloride solution. A voltage of 1.5V was applied to accelerate corrosion. Electrochemical monitoring was carried out every 12 hours of acceleration, for a total of 240 hours. The steel bars began to corrode after 204 hours.

[0049] Example 3:

[0050] The chloride-resistant geopolymer concrete material of this embodiment includes solid powder, aggregate, and alkali activator; the solid powder contains 10 wt% fly ash and 90 wt% slag; the aggregate contains 60 wt% iron tailings and 40 wt% fine sand. The alkali activator contains 30 wt% water glass, 7.5 wt% solid sodium hydroxide, and 5 wt% calcium carbide slag; the water-to-solid ratio is 0.6; and the solution modulus of the alkali activator is 1.

[0051] In preparation, 30g of fly ash and 270g of slag are weighed and mixed evenly to obtain solid powder. 360g of iron tailings and 240g of fine sand are weighed and mixed evenly to obtain aggregate. The aggregate and solid powder are mixed evenly to obtain solid mixture A. 15g of calcium carbide slag is weighed and dissolved in 50g of water. 22.5g of sodium hydroxide is weighed and dissolved in 71.32g of water. After the sodium hydroxide solution is clarified, 90g of water glass is added, stirred evenly, and allowed to stand for 24 hours. The settled sodium hydroxide and water glass mixture is poured into the calcium carbide slag solution to obtain an alkali activator. The solid mixture A is mixed with the alkali activator and stirred for 5 minutes to obtain a slurry B, which is poured into a 30mm×30mm×30mm steel mold containing reinforcing bars. The slurry was poured into a cylindrical mold and continuously vibrated to expel air. The sample was sealed together with the mold and cured in an oven at 60°C for 6 hours. After demolding, it was cured at room temperature for 14 days.

[0052] The cured cubic specimens were used for compressive strength testing, and the cured cylindrical specimens with embedded steel bars were used for chloride salt resistance testing. The compressive strength test was carried out for 14 days on an integrated compression and flexural strength testing machine. The part of the cylindrical specimen with embedded steel bars exposed to air was sealed, and the rest was completely immersed in a 3.5wt% sodium chloride solution. A voltage of 1.5V was applied to accelerate corrosion. Electrochemical monitoring was carried out every 12 hours of acceleration, for a total of 240 hours. The steel bars began to corrode after 204 hours.

[0053] Example 4:

[0054] The chloride-resistant geopolymer concrete material of this embodiment includes solid powder, aggregate, and alkali activator; the solid powder contains 10 wt% fly ash and 90 wt% slag; the aggregate contains 20 wt% iron tailings and 80 wt% fine sand. The alkali activator contains 45 wt% water glass, 11 wt% solid sodium hydroxide, and 5 wt% calcium carbide slag, with a water-to-solid ratio of 0.6 and a solution modulus of 1.

[0055] In preparation, 30g of fly ash and 270g of slag are weighed and mixed evenly to obtain solid powder. 120g of iron tailings and 480g of fine sand are weighed and mixed evenly to obtain aggregate. The aggregate and solid powder are mixed evenly to obtain solid mixture A. 15g of calcium carbide slag is weighed and dissolved in 20g of water. 33g of sodium hydroxide is weighed and dissolved in 71.98g of water. After the sodium hydroxide solution is clarified, 135g of water glass is added, stirred evenly, and allowed to stand for 24 hours. The settled sodium hydroxide and water glass mixture is poured into the calcium carbide slag solution to obtain an alkali activator. The solid mixture A is mixed with the alkali activator and stirred for 5 minutes to obtain a slurry B, which is poured into a 30mm×30mm×30mm steel mold containing reinforcing bars. The slurry was poured into a cylindrical mold and continuously vibrated to expel air. The sample was sealed together with the mold and cured in an oven at 60°C for 6 hours. After demolding, it was cured at room temperature for 14 days.

[0056] The cured cubic specimens were used for compressive strength testing, and the cured cylindrical specimens with embedded steel bars were used for chloride salt resistance testing. The compressive strength test was carried out for 14 days on an integrated compression and flexural strength tester. The part of the cylindrical specimen with embedded steel bars exposed to air was sealed, and the rest was completely immersed in a 3.5wt% sodium chloride solution. A voltage of 1.5V was applied to accelerate corrosion. Electrochemical monitoring was carried out every 12 hours of acceleration, for a total of 240 hours. The steel bars began to corrode after 228 hours.

[0057] Example 5:

[0058] The chloride-resistant geopolymer concrete material of this embodiment includes solid powder, aggregate, and alkali activator; the solid powder contains 10 wt% fly ash and 90 wt% slag; the aggregate contains 20 wt% iron tailings and 80 wt% fine sand. The alkali activator contains 45 wt% water glass, 11 wt% solid sodium hydroxide, and 1 wt% calcium carbide slag; the water-to-solid ratio is 0.6; and the solution modulus of the alkali activator is 1.

[0059] In preparation, 30g of fly ash and 270g of slag are weighed and mixed evenly to obtain solid powder. 120g of iron tailings and 480g of fine sand are weighed and mixed evenly to obtain aggregate. The aggregate and solid powder are mixed evenly to obtain solid mixture A. 3g of calcium carbide slag is weighed and dissolved in 20g of water. 33g of sodium hydroxide is weighed and dissolved in 71.98g of water. After the sodium hydroxide solution is clarified, 135g of water glass is added, stirred evenly, and allowed to stand for 24 hours. The settled sodium hydroxide and water glass mixture is poured into the calcium carbide slag solution to obtain an alkali activator. The solid mixture A is mixed with the alkali activator and stirred for 5 minutes to obtain a slurry B, which is poured into a 30mm×30mm×30mm steel mold containing reinforcing bars. The slurry was poured into a cylindrical mold and continuously vibrated to expel air. The sample was sealed together with the mold and cured in an oven at 60°C for 6 hours. After demolding, it was cured at room temperature for 14 days.

[0060] The cured cubic specimens were used for compressive strength testing, and the cured cylindrical specimens with embedded steel bars were used for chloride salt resistance testing. The compressive strength test was carried out for 14 days on an integrated compression and flexural strength tester. The part of the cylindrical specimen with embedded steel bars exposed to air was sealed, and the rest was completely immersed in a 3.5wt% sodium chloride solution. A voltage of 1.5V was applied to accelerate corrosion. Electrochemical monitoring was carried out every 12 hours of acceleration, for a total of 240 hours. The steel bars began to corrode after 228 hours.

[0061] Example 6:

[0062] The chloride-resistant geopolymer concrete material of this embodiment includes solid powder, aggregate, and alkali activator; the solid powder contains 10 wt% fly ash and 90 wt% slag; the aggregate contains 60 wt% iron tailings and 40 wt% fine sand. The alkali activator contains 45 wt% water glass, 11 wt% solid sodium hydroxide, and 15 wt% calcium carbide slag; the water-to-solid ratio is 0.6; and the solution modulus of the alkali activator is 1.

[0063] In preparation, 30g of fly ash and 270g of slag are weighed and mixed evenly to obtain solid powder. 360g of iron tailings and 240g of fine sand are weighed and mixed evenly to obtain aggregate. The aggregate and solid powder are mixed evenly to obtain solid mixture A. 15g of calcium carbide slag is weighed and dissolved in 20g of water. 33g of sodium hydroxide is weighed and dissolved in 71.98g of water. After the sodium hydroxide solution is clarified, 135g of water glass is added, stirred evenly, and allowed to stand for 24 hours. The settled sodium hydroxide and water glass mixture is poured into the calcium carbide slag solution to obtain an alkali activator. The solid mixture A is mixed with the alkali activator and stirred for 5 minutes to obtain a slurry B, which is poured into a 30mm×30mm×30mm steel mold containing reinforcing bars. The slurry was poured into a cylindrical mold and continuously vibrated to expel air. The sample was sealed together with the mold and cured in an oven at 60°C for 6 hours. After demolding, it was cured at room temperature for 14 days.

[0064] The cured cubic specimens were used for compressive strength testing, and the cured cylindrical specimens with embedded steel bars were used for chloride salt resistance testing. The compressive strength test was carried out for 14 days on a combined compressive and flexural strength tester. The part of the cylindrical specimen with embedded steel bars exposed to air was sealed, and the rest was completely immersed in a 3.5wt% sodium chloride solution. A voltage of 1.5V was applied to accelerate corrosion. Electrochemical monitoring was carried out every 12 hours of acceleration, for a total of 240 hours. The steel bars began to corrode after 216 hours.

[0065] Example 7:

[0066] The chloride-resistant geopolymer concrete material of this embodiment includes solid powder, aggregate, and alkali activator; the solid powder contains 10 wt% fly ash and 90 wt% slag; the aggregate contains 60 wt% iron tailings and 40 wt% fine sand. The alkali activator contains 45 wt% water glass, 11 wt% solid sodium hydroxide, and 1 wt% calcium carbide slag; the water-to-solid ratio is 0.6; and the solution modulus of the alkali activator is 1.

[0067] In preparation, 30g of fly ash and 270g of slag are weighed and mixed evenly to obtain solid powder. 360g of iron tailings and 240g of fine sand are weighed and mixed evenly to obtain aggregate. The aggregate and solid powder are mixed evenly to obtain solid mixture A. 3g of calcium carbide slag is weighed and dissolved in 20g of water. 33g of sodium hydroxide is weighed and dissolved in 71.98g of water. After the sodium hydroxide solution is clarified, 135g of water glass is added, stirred evenly, and allowed to stand for 24 hours. The settled sodium hydroxide and water glass mixture is poured into the calcium carbide slag solution to obtain an alkali activator. The solid mixture A is mixed with the alkali activator and stirred for 5 minutes to obtain a slurry B, which is poured into a 30mm×30mm×30mm steel mold containing reinforcing bars. The slurry was poured into a cylindrical mold and continuously vibrated to expel air. The sample was sealed together with the mold and cured in an oven at 60°C for 6 hours. After demolding, it was cured at room temperature for 14 days.

[0068] The cured cubic specimens were used for compressive strength testing, and the cured cylindrical specimens with embedded steel bars were used for chloride salt resistance testing. The compressive strength test was carried out for 14 days on a combined compressive and flexural strength tester. The part of the cylindrical specimen with embedded steel bars exposed to air was sealed, and the rest was completely immersed in a 3.5wt% sodium chloride solution. A voltage of 1.5V was applied to accelerate corrosion. Electrochemical monitoring was carried out every 12 hours of acceleration, for a total of 240 hours. The steel bars began to corrode after 216 hours.

[0069] Example 8:

[0070] The chloride-resistant geopolymer concrete material of this embodiment includes solid powder, aggregate, and alkali activator; the solid powder contains 50 wt% fly ash and 50 wt% slag; the aggregate contains 60 wt% iron tailings and 40 wt% fine sand. The alkali activator contains 30 wt% water glass, 7.5 wt% solid sodium hydroxide, and 1 wt% calcium carbide slag; the water-to-solid ratio is 0.6; and the solution modulus of the alkali activator is 1.

[0071] In preparation, 150g of fly ash and 150g of slag are weighed and mixed evenly to obtain solid powder. 360g of iron tailings and 240g of fine sand are weighed and mixed evenly to obtain aggregate. The aggregate and solid powder are mixed evenly to obtain solid mixture A. 3g of calcium carbide slag is weighed and dissolved in 50g of water. 22.5g of sodium hydroxide is weighed and dissolved in 71.32g of water. After the sodium hydroxide solution is clarified, 90g of water glass is added, stirred evenly, and allowed to stand for 24 hours. The settled sodium hydroxide and water glass mixture is poured into the calcium carbide slag solution to obtain an alkali activator. The solid mixture A and alkali activator are mixed and stirred for 5 minutes to obtain mixture slurry B, which is poured into a 30mm×30mm×30mm steel mold containing reinforcing bars. The slurry was poured into a cylindrical mold and continuously vibrated to expel air. The sample was sealed together with the mold and cured in an oven at 60°C for 6 hours. After demolding, it was cured at room temperature for 14 days.

[0072] The cured cubic specimens were used for compressive strength testing, and the cured cylindrical specimens with embedded steel bars were used for chloride salt resistance testing. The compressive strength test was carried out for 14 days on an integrated compression and flexural strength testing machine. The part of the cylindrical specimen with embedded steel bars exposed to air was sealed, and the rest was completely immersed in a 3.5wt% sodium chloride solution. A voltage of 1.5V was applied to accelerate corrosion. Electrochemical monitoring was carried out every 12 hours of acceleration, for a total of 240 hours. The steel bars began to corrode after 204 hours.

[0073] Example 9:

[0074] The chloride-resistant geopolymer concrete material of this embodiment includes solid powder, aggregate, and alkali activator; the solid powder contains 50 wt% fly ash and 50 wt% slag; the aggregate contains 20 wt% iron tailings and 80 wt% fine sand. The alkali activator contains 30 wt% water glass, 7.5 wt% solid sodium hydroxide, and 1 wt% calcium carbide slag; the water-to-solid ratio is 0.6; and the solution modulus of the alkali activator is 1.

[0075] In preparation, 150g of fly ash and 150g of slag are weighed and mixed evenly to obtain solid powder. 120g of iron tailings and 480g of fine sand are weighed and mixed evenly to obtain aggregate. The aggregate and solid powder are mixed evenly to obtain solid mixture A. 3g of calcium carbide slag is weighed and dissolved in 50g of water. 22.5g of sodium hydroxide is weighed and dissolved in 71.32g of water. After the sodium hydroxide solution is clarified, 90g of water glass is added, stirred evenly, and allowed to stand for 24 hours. The settled sodium hydroxide and water glass mixture is poured into the calcium carbide slag solution to obtain an alkali activator. The solid mixture A is mixed with the alkali activator and stirred for 5 minutes to obtain a slurry B, which is poured into a 30mm×30mm×30mm steel mold containing reinforcing bars. The slurry was poured into a cylindrical mold and continuously vibrated to expel air. The sample was sealed together with the mold and cured in an oven at 60°C for 6 hours. After demolding, it was cured at room temperature for 14 days.

[0076] The cured cubic specimens were used for compressive strength testing, and the cured cylindrical specimens with embedded steel bars were used for chloride salt resistance testing. The compressive strength test was carried out for 14 days on an integrated compression and flexural strength testing machine. The part of the cylindrical specimen with embedded steel bars exposed to air was sealed, and the rest was completely immersed in a 3.5wt% sodium chloride solution. A voltage of 1.5V was applied to accelerate corrosion. Electrochemical monitoring was carried out every 12 hours of acceleration, for a total of 240 hours. The steel bars began to corrode after 204 hours.

[0077] Example 10:

[0078] The chloride-resistant geopolymer concrete material of this embodiment includes solid powder, aggregate, and alkali activator; the solid powder contains 50 wt% fly ash and 50 wt% slag; the aggregate contains 20 wt% iron tailings and 80 wt% fine sand. The alkali activator contains 30 wt% water glass, 7.5 wt% solid sodium hydroxide, and 5 wt% calcium carbide slag; the water-to-solid ratio is 0.6; and the solution modulus of the alkali activator is 1.

[0079] In preparation, 150g of fly ash and 150g of slag are weighed and mixed evenly to obtain solid powder. 120g of iron tailings and 480g of fine sand are weighed and mixed evenly to obtain aggregate. The aggregate and solid powder are mixed evenly to obtain solid mixture A. 15g of carbide slag is weighed and dissolved in 50g of water. 22.5g of sodium hydroxide is weighed and dissolved in 71.32g of water. After the sodium hydroxide solution is clarified, 90g of water glass is added, stirred evenly, and allowed to stand for 24 hours. The settled sodium hydroxide and water glass mixture is poured into the carbide slag solution to obtain an alkali activator. The solid mixture A is mixed with the alkali activator and stirred for 5 minutes to obtain a slurry B, which is poured into a 30mm×30mm×30mm steel mold containing reinforcing bars. The slurry was poured into a cylindrical mold and continuously vibrated to expel air. The sample was sealed together with the mold and cured in an oven at 60°C for 6 hours. After demolding, it was cured at room temperature for 14 days.

[0080] The cured cubic specimens were used for compressive strength testing, and the cured cylindrical specimens with embedded steel bars were used for chloride salt resistance testing. The compressive strength test was carried out for 14 days on an integrated compression and flexural strength testing machine. The part of the cylindrical specimen with embedded steel bars exposed to air was sealed, and the rest was completely immersed in a 3.5wt% sodium chloride solution. A voltage of 1.5V was applied to accelerate corrosion. Electrochemical monitoring was carried out every 12 hours of acceleration, for a total of 240 hours. The steel bars began to corrode after 204 hours.

[0081] Example 11:

[0082] The chloride-resistant geopolymer concrete material of this embodiment includes solid powder, aggregate, and alkali activator; the solid powder contains 50 wt% fly ash and 50 wt% slag; the aggregate contains 60 wt% iron tailings and 40 wt% fine sand. The alkali activator contains 45 wt% water glass, 11 wt% solid sodium hydroxide, and 5 wt% calcium carbide slag, with a water-to-solid ratio of 0.6 and a solution modulus of 1.

[0083] In preparation, 150g of fly ash and 150g of slag are weighed and mixed evenly to obtain solid powder. 360g of iron tailings and 240g of fine sand are weighed and mixed evenly to obtain aggregate. The aggregate and solid powder are mixed evenly to obtain solid mixture A. 15g of calcium carbide slag is weighed and dissolved in 20g of water. 33g of sodium hydroxide is weighed and dissolved in 71.98g of water. After the sodium hydroxide solution is clarified, 135g of water glass is added, stirred evenly, and allowed to stand for 24 hours. The settled sodium hydroxide and water glass mixture is poured into the calcium carbide slag solution to obtain an alkali activator. The solid mixture A is mixed with the alkali activator and stirred for 5 minutes to obtain a slurry B, which is poured into a 30mm×30mm×30mm steel mold containing reinforcing bars. The slurry was poured into a cylindrical mold and continuously vibrated to expel air. The sample was sealed together with the mold and cured in an oven at 60°C for 6 hours. After demolding, it was cured at room temperature for 14 days.

[0084] The cured cubic specimens were used for compressive strength testing, and the cured cylindrical specimens with embedded steel bars were used for chloride salt resistance testing. The compressive strength test was carried out for 14 days on an integrated compression and flexural strength testing machine. The part of the cylindrical specimen with embedded steel bars exposed to air was sealed, and the rest was completely immersed in a 3.5wt% sodium chloride solution. A voltage of 1.5V was applied to accelerate corrosion. Electrochemical monitoring was carried out every 12 hours of acceleration, for a total of 240 hours. The steel bars began to corrode after 204 hours.

[0085] Example 12:

[0086] The chloride-resistant geopolymer concrete material of this embodiment includes solid powder, aggregate, and alkali activator; the solid powder contains 50 wt% fly ash and 50 wt% slag; the aggregate contains 20 wt% iron tailings and 80 wt% fine sand. The alkali activator contains 45 wt% water glass, 11 wt% solid sodium hydroxide, and 5 wt% calcium carbide slag, with a water-to-solid ratio of 0.6 and a solution modulus of 1.

[0087] In preparation, 150g of fly ash and 150g of slag are weighed and mixed evenly to obtain solid powder. 120g of iron tailings and 480g of fine sand are weighed and mixed evenly to obtain aggregate. The aggregate and solid powder are mixed evenly to obtain solid mixture A. 15g of calcium carbide slag is weighed and dissolved in 20g of water. 33g of sodium hydroxide is weighed and dissolved in 71.98g of water. After the sodium hydroxide solution is clarified, 135g of water glass is added, stirred evenly, and allowed to stand for 24 hours. The settled sodium hydroxide and water glass mixture is poured into the calcium carbide slag solution to obtain an alkali activator. The solid mixture A is mixed with the alkali activator and stirred for 5 minutes to obtain a slurry B, which is poured into a 30mm×30mm×30mm steel mold containing reinforcing bars. The slurry was poured into a cylindrical mold and continuously vibrated to expel air. The sample was sealed together with the mold and cured in an oven at 60°C for 6 hours. After demolding, it was cured at room temperature for 14 days.

[0088] The cured cubic specimens were used for compressive strength testing, and the cured cylindrical specimens with embedded steel bars were used for chloride salt resistance testing. The compressive strength test was carried out for 14 days on a combined compressive and flexural strength tester. The part of the cylindrical specimen with embedded steel bars exposed to air was sealed, and the rest was completely immersed in a 3.5wt% sodium chloride solution. A voltage of 1.5V was applied to accelerate corrosion. Electrochemical monitoring was carried out every 12 hours of acceleration, for a total of 240 hours. The steel bars began to corrode after 216 hours.

[0089] Example 13:

[0090] The chloride-resistant geopolymer concrete material of this embodiment includes solid powder, aggregate, and alkali activator; the solid powder contains 50 wt% fly ash and 50 wt% slag; the aggregate contains 20 wt% iron tailings and 80 wt% fine sand. The alkali activator contains 45 wt% water glass, 11 wt% solid sodium hydroxide, and 1 wt% calcium carbide slag, with a water-to-solid ratio of 0.6 and a solution modulus of 1.

[0091] In preparation, 150g of fly ash and 150g of slag are weighed and mixed evenly to obtain solid powder. 120g of iron tailings and 480g of fine sand are weighed and mixed evenly to obtain aggregate. The aggregate and solid powder are mixed evenly to obtain solid mixture A. 3g of calcium carbide slag is weighed and dissolved in 20g of water. 33g of sodium hydroxide is weighed and dissolved in 71.98g of water. After the sodium hydroxide solution is clarified, 135g of water glass is added, stirred evenly, and allowed to stand for 24 hours. The settled sodium hydroxide and water glass mixture is poured into the calcium carbide slag solution to obtain an alkali activator. The solid mixture A is mixed with the alkali activator and stirred for 5 minutes to obtain a slurry B, which is poured into a 30mm×30mm×30mm steel mold containing reinforcing steel. The slurry was poured into a cylindrical mold and continuously vibrated to expel air. The sample was sealed together with the mold and cured in an oven at 60°C for 6 hours. After demolding, it was cured at room temperature for 14 days.

[0092] The cured cubic specimens were used for compressive strength testing, and the cured cylindrical specimens with embedded steel bars were used for chloride salt resistance testing. The compressive strength test was carried out for 14 days on a combined compressive and flexural strength tester. The part of the cylindrical specimen with embedded steel bars exposed to air was sealed, and the rest was completely immersed in a 3.5wt% sodium chloride solution. A voltage of 1.5V was applied to accelerate corrosion. Electrochemical monitoring was carried out every 12 hours of acceleration, for a total of 240 hours. The steel bars began to corrode after 216 hours.

[0093] Example 14:

[0094] The chloride-resistant geopolymer concrete material of this embodiment includes solid powder, aggregate, and alkali activator; the solid powder contains 10 wt% fly ash and 90 wt% slag; the aggregate contains 20 wt% iron tailings and 80 wt% fine sand. The alkali activator contains 45 wt% water glass, 11 wt% solid sodium hydroxide, and 3 wt% calcium carbide slag, with a water-to-solid ratio of 0.6 and a solution modulus of 1.

[0095] In preparation, 30g of fly ash and 270g of slag are weighed and mixed evenly to obtain solid powder. 120g of iron tailings and 480g of fine sand are weighed and mixed evenly to obtain aggregate. The aggregate and solid powder are mixed evenly to obtain solid mixture A. 9g of calcium carbide slag is weighed and dissolved in 20g of water. 33g of sodium hydroxide is weighed and dissolved in 71.98g of water. After the sodium hydroxide solution is clarified, 135g of water glass is added, stirred evenly, and allowed to stand for 24 hours. The settled sodium hydroxide and water glass mixture is poured into the calcium carbide slag solution to obtain an alkali activator. Solid mixture A is mixed with the alkali activator and stirred for 5 minutes to obtain mixture slurry B. This slurry is poured into a 30mm×30mm×30mm steel mold containing reinforcing bars. The slurry was poured into a cylindrical mold and continuously vibrated to expel air. The sample was sealed together with the mold and cured in an oven at 60°C for 6 hours. After demolding, it was cured at room temperature for 14 days.

[0096] The cured cubic specimens were used for compressive strength testing, and the cured cylindrical specimens with embedded steel bars were used for chloride salt resistance testing. The compressive strength test was carried out for 14 days on an integrated compression and flexural strength testing machine. The part of the cylindrical specimen with embedded steel bars exposed to air was sealed, and the rest was completely immersed in a 3.5wt% sodium chloride solution. A voltage of 1.5V was applied to accelerate corrosion. Electrochemical monitoring was carried out every 12 hours of acceleration, for a total of 240 hours. The steel bars had not started to corrode after 240 hours.

[0097] The mechanical properties of the chloride-resistant geopolymer concretes prepared in Examples 1-14 were tested, and the results are shown in Table 1.

[0098] Table 1. Test results of the mechanical properties of chloride-resistant geopolymers obtained in Examples 1-14

[0099]

[0100] like Figure 3 As shown in Table 1, the chloride-resistant geopolymer concretes prepared in each embodiment exhibit high compressive strength, and the corrosion initiation time is after 200 hours. The principle behind this is that fly ash and slag contain a large amount of active silica-alumina compounds, while water glass, solid sodium hydroxide, and carbide slag are highly alkaline. Under high alkalinity, the active silica-alumina compounds in fly ash and slag undergo depolymerization followed by repolymerization, ultimately cross-linking to form a three-dimensional network structure. This significantly reduces the internal pore size, resulting in a denser structure and a marked improvement in the mechanical properties of the geopolymer. Furthermore, in the system of Example 14, where calcium and aluminum content is high, these components are easily chemically combined to form Friedel's salts, which are also easily physically adsorbed within the three-dimensional network structure. This further hinders chloride ion erosion, resulting in good chloride-resistant performance of the geopolymer under these conditions.

[0101] Comparative Example 1:

[0102] The chloride-resistant geopolymer concrete material in this comparative example includes solid powder, aggregate, and alkali activator; the solid powder contains 10 wt% fly ash and 90 wt% slag; the aggregate contains 20 wt% iron tailings and 80 wt% fine sand. Solid sodium hydroxide and calcium carbide slag are used as alkali activators, with the solid sodium hydroxide content being 11 wt% of the solid powder and the calcium carbide slag content being 18.66 wt% of the solid powder, and the water-to-solid ratio being 0.6.

[0103] In preparation, 30g of fly ash and 270g of slag are weighed and mixed evenly to obtain solid powder. 120g of iron tailings and 480g of fine sand are weighed and mixed evenly to obtain aggregate. The aggregate and solid powder are mixed evenly to obtain solid mixture A. 55.98g of calcium carbide slag is weighed and dissolved in 80g of water. 33g of sodium hydroxide is weighed and dissolved in 100g of water and left to stand for 24 hours. The sodium hydroxide solution is poured into the calcium carbide slag solution to obtain an alkali activator. The solid mixture A is mixed with the alkali activator and stirred for 5 minutes to obtain mixture slurry B. This slurry is poured into a 30mm×30mm×30mm steel mold containing reinforcing bars. The slurry was poured into a cylindrical mold and continuously vibrated to expel air. The sample was sealed together with the mold and cured in an oven at 60°C for 6 hours. After demolding, it was cured at room temperature for 14 days.

[0104] The cured cubic specimens were used for compressive strength testing, and the cured cylindrical specimens with embedded steel bars were used for chloride salt resistance testing. The compressive strength test was carried out for 14 days on an integrated compression and flexural strength testing machine. The part of the cylindrical specimen with embedded steel bars exposed to air was sealed, and the rest was completely immersed in a 3.5wt% sodium chloride solution. A voltage of 1.5V was applied to accelerate corrosion. Electrochemical monitoring was carried out every 12 hours of acceleration, for a total of 240 hours. The steel bars began to corrode after 144 hours.

[0105] Comparative Example 2:

[0106] The chloride-resistant geopolymer concrete material in this comparative example includes solid powder, aggregate, and alkali activator; the solid powder contains 10 wt% fly ash and 90 wt% slag; the aggregate contains 20 wt% iron tailings and 80 wt% fine sand. Water glass and calcium carbide slag are used as alkali activators, with water glass accounting for 45 wt% of the solid powder and calcium carbide slag accounting for 14 wt%, and the water-to-solid ratio is 0.6.

[0107] In preparation, 30g of fly ash and 270g of slag are weighed and mixed evenly to obtain solid powder. 120g of iron tailings and 480g of fine sand are weighed and mixed evenly to obtain aggregate. The aggregate and solid powder are mixed evenly to obtain solid mixture A. 42g of calcium carbide slag is weighed and dissolved in 91.98g of water. 135g of water glass is weighed and added to the calcium carbide slag solution to obtain an alkali activator. The solid mixture A and the alkali activator are mixed and stirred for 5 minutes to obtain a slurry B, which is poured into a 30mm×30mm×30mm steel mold containing reinforcing bars. The slurry was poured into a cylindrical mold and continuously vibrated to expel air. The sample was sealed together with the mold and cured in an oven at 60°C for 6 hours. After demolding, it was cured at room temperature for 14 days.

[0108] The cured cubic specimens were used for compressive strength testing, and the cured cylindrical specimens with embedded steel bars were used for chloride salt resistance testing. The compressive strength test was carried out for 14 days on an integrated compression and flexural strength testing machine. The part of the cylindrical specimen with embedded steel bars exposed to air was sealed, and the rest was completely immersed in a 3.5wt% sodium chloride solution. A voltage of 1.5V was applied to accelerate corrosion. Electrochemical monitoring was carried out every 12 hours of acceleration, for a total of 240 hours. The steel bars began to corrode after 132 hours.

[0109] Comparative Example 3:

[0110] The chloride-resistant geopolymer concrete material in this comparative example includes solid powder, aggregate, and alkali activator; the solid powder contains 10 wt% fly ash and 90 wt% slag; the aggregate contains 20 wt% iron tailings and 80 wt% fine sand. Water glass and solid sodium hydroxide are used as alkali activators, with water glass accounting for 45 wt% of the solid powder and solid sodium hydroxide accounting for 14 wt%, resulting in a water-to-solid ratio of 0.6.

[0111] In preparation, 30g of fly ash and 270g of slag are weighed and mixed evenly to obtain solid powder. 120g of iron tailings and 480g of fine sand are weighed and mixed evenly to obtain aggregate. The aggregate and solid powder are mixed evenly to obtain solid mixture A. 42g of sodium hydroxide is dissolved in 91.98g of water, and 135g of water glass is added to the sodium hydroxide solution to obtain an alkali activator. The solid mixture A and the alkali activator are mixed and stirred for 5 minutes to obtain mixture slurry B, which is poured into a 30mm×30mm×30mm steel mold containing reinforcing bars. The slurry was poured into a cylindrical mold and continuously vibrated to expel air. The sample was sealed together with the mold and cured in an oven at 60°C for 6 hours. After demolding, it was cured at room temperature for 14 days.

[0112] The cured cubic specimens were used for compressive strength testing, and the cured cylindrical specimens with embedded steel bars were used for chloride salt resistance testing. The compressive strength test was carried out for 14 days on an integrated compression and flexural strength testing machine. The part of the cylindrical specimen with embedded steel bars exposed to air was sealed, and the rest was completely immersed in a 3.5wt% sodium chloride solution. A voltage of 1.5V was applied to accelerate corrosion. Electrochemical monitoring was carried out every 12 hours of acceleration, for a total of 240 hours. The steel bars began to corrode after 120 hours.

[0113] Comparative Example 4:

[0114] The chloride-resistant geopolymer concrete material in this comparative example includes solid powder, aggregate, and alkali activator; the fly ash content in the solid powder is 100 wt%; the iron tailings content in the aggregate is 20 wt%, and the fine sand content is 80 wt%. Water glass and solid sodium hydroxide are used as alkali activators, with the water glass content being 45 wt% of the solid powder, the solid sodium hydroxide content being 11 wt%, the calcium carbide slag content being 3 wt%, and the water-to-solid ratio being 0.6.

[0115] In preparation, 300g of fly ash is weighed and mixed evenly to obtain solid powder. 120g of iron tailings and 480g of fine sand are weighed and mixed evenly to obtain aggregate. The aggregate and solid powder are mixed evenly to obtain solid mixture A. 33g of sodium hydroxide is weighed and dissolved in 71.98g of water. 9g of carbide slag is weighed and dissolved in 20g of water. 135g of water glass is weighed and added to the sodium hydroxide solution and left to stand for 24 hours. After standing, it is poured into the carbide slag solution to obtain an alkali activator. The solid mixture A and the alkali activator are mixed and stirred for 5 minutes to obtain mixture slurry B, which is poured into a 30mm×30mm×30mm steel mold containing reinforcing bars. The slurry was poured into a cylindrical mold and continuously vibrated to expel air. The sample was sealed together with the mold and cured in an oven at 60°C for 6 hours. After demolding, it was cured at room temperature for 14 days.

[0116] The cured cubic specimens were used for compressive strength testing, and the cured cylindrical specimens with embedded steel bars were used for chloride salt resistance testing. The compressive strength test was carried out for 14 days on an integrated compression and flexural strength testing machine. The part of the cylindrical specimen with embedded steel bars exposed to air was sealed, and the rest was completely immersed in a 3.5wt% sodium chloride solution. A voltage of 1.5V was applied to accelerate corrosion. Electrochemical monitoring was carried out every 12 hours of acceleration, for a total of 240 hours. The steel bars began to corrode after 132 hours.

[0117] Comparative Example 5:

[0118] The chloride-resistant geopolymer concrete material of this comparative example includes solid powder, aggregate, and alkali activator; the solid powder contains 10 wt% fly ash and 90 wt% slag; the aggregate contains 100 wt% iron tailings. Water glass and solid sodium hydroxide are used as alkali activators, with water glass accounting for 45 wt% of the solid powder and solid sodium hydroxide accounting for 11 wt%, and the water-to-solid ratio is 0.6.

[0119] In preparation, 30g of fly ash and 270g of slag are weighed and mixed evenly to obtain solid powder. 600g of iron tailings are weighed and mixed evenly to obtain aggregate. The aggregate and solid powder are mixed evenly to obtain solid mixture A. 33g of sodium hydroxide is dissolved in 71.98g of water, 9g of carbide slag is dissolved in 20g of water, and 135g of water glass is added to the sodium hydroxide solution and left to stand for 24 hours. After standing, it is poured into the carbide slag solution to obtain an alkali activator. The solid mixture A is mixed with the alkali activator and stirred for 5 minutes to obtain mixture slurry B, which is poured into a 30mm×30mm×30mm steel mold containing reinforcing bars. The slurry was poured into a cylindrical mold and continuously vibrated to expel air. The sample was sealed together with the mold and cured in an oven at 60°C for 6 hours. After demolding, it was cured at room temperature for 14 days.

[0120] The cured cubic specimens were used for compressive strength testing, and the cured cylindrical specimens with embedded steel bars were used for chloride salt resistance testing. The compressive strength test was carried out for 14 days on an integrated compression and flexural strength testing machine. The part of the cylindrical specimen with embedded steel bars exposed to air was sealed, and the rest was completely immersed in a 3.5wt% sodium chloride solution. A voltage of 1.5V was applied to accelerate corrosion. Electrochemical monitoring was carried out every 12 hours of acceleration, for a total of 240 hours. The steel bars began to corrode after 180 hours.

[0121] Comparative Example 6:

[0122] The chloride-resistant geopolymer concrete material in this comparative example includes solid powder, aggregate, and alkali activator; the fly ash content in the solid powder is 100 wt%; the iron tailings content in the aggregate is 20 wt%, and the fine sand content is 80 wt%. Solid sodium hydroxide and calcium carbide slag are used as alkali activators, with the solid sodium hydroxide content in the alkali activator being 11 wt% of the solid powder mass, the calcium carbide slag content being 18.66 wt% of the solid powder mass, and the water-to-solid ratio being 0.6.

[0123] In preparation, 100g of fly ash is weighed and stirred evenly to obtain solid powder. 120g of iron tailings and 480g of fine sand are weighed and mixed evenly to obtain aggregate. The aggregate and solid powder are mixed evenly to obtain solid mixture A. 55.98g of carbide slag is weighed and dissolved in 80g of water. 33g of sodium hydroxide is weighed and dissolved in 100g of water and left to stand for 24 hours. The sodium hydroxide solution is poured into the carbide slag solution to obtain an alkali activator. The solid mixture A is mixed with the alkali activator and stirred for 5 minutes to obtain mixture slurry B. This slurry is poured into a 30mm×30mm×30mm steel mold containing reinforcing bars. The slurry was poured into a cylindrical mold and continuously vibrated to expel air. The sample was sealed together with the mold and cured in an oven at 60°C for 6 hours. After demolding, it was cured at room temperature for 14 days.

[0124] The cured cubic specimens were used for compressive strength testing, and the cured cylindrical specimens with embedded steel bars were used for chloride salt resistance testing. The compressive strength test was carried out for 14 days on the integrated compressive and flexural strength test machine. The part of the cylindrical specimen with embedded steel bars exposed to air was sealed, and the rest was completely immersed in a 3.5wt% sodium chloride solution. A voltage of 1.5V was applied to accelerate corrosion. Electrochemical monitoring was carried out every 12 hours of acceleration, for a total of 240 hours. The steel began to corrode after 132 hours.

[0125] Comparative Example 7:

[0126] The chloride-resistant geopolymer concrete material in this comparative example includes solid powder, aggregate, and alkali activator; the fly ash content in the solid powder is 100 wt%; the iron tailings content in the aggregate is 20 wt%, and the fine sand content is 80 wt%. Water glass and calcium carbide slag are used as alkali activators, with the water glass content in the alkali activator being 45 wt% of the solid powder and the calcium carbide slag content being 14 wt% of the solid powder, and the water-to-solid ratio being 0.6.

[0127] In preparation, 300g of fly ash is weighed and stirred evenly to obtain solid powder. 120g of iron tailings and 480g of fine sand are weighed and mixed evenly to obtain aggregate. The aggregate and solid powder are then mixed evenly to obtain solid mixture A. 42g of calcium carbide slag is weighed and dissolved in 91.98g of water. 135g of water glass is weighed and added to the calcium carbide slag solution to obtain an alkali activator. The solid mixture A and the alkali activator are mixed and stirred for 5 minutes to obtain a slurry B, which is then poured into a 30mm×30mm×30mm steel mold containing reinforcing bars. The slurry was poured into a cylindrical mold and continuously vibrated to expel air. The sample was sealed together with the mold and cured in an oven at 60°C for 6 hours. After demolding, it was cured at room temperature for 14 days.

[0128] The cured cubic specimens were used for compressive strength testing, and the cured cylindrical specimens with embedded steel bars were used for chloride salt resistance testing. The compressive strength test was carried out for 14 days on an integrated compression and flexural strength testing machine. The part of the cylindrical specimen with embedded steel bars exposed to air was sealed, and the rest was completely immersed in a 3.5wt% sodium chloride solution. A voltage of 1.5V was applied to accelerate corrosion. Electrochemical monitoring was carried out every 12 hours of acceleration, for a total of 240 hours. The steel bars began to corrode after 132 hours.

[0129] Comparative Example 8:

[0130] The chloride-resistant geopolymer concrete material in this comparative example includes solid powder, aggregate, and alkali activator; the fly ash content in the solid powder is 100 wt%; the iron tailings content in the aggregate is 20 wt%, and the fine sand content is 80 wt%. Water glass and solid sodium hydroxide are used as alkali activators, with the water glass content in the alkali activator being 45 wt% of the solid powder and the solid sodium hydroxide content being 14 wt% of the solid powder, resulting in a water-to-solid ratio of 0.6.

[0131] In preparation, 300g of fly ash is weighed and stirred evenly to obtain solid powder. 120g of iron tailings and 480g of fine sand are weighed and mixed evenly to obtain aggregate. The aggregate and solid powder are then mixed evenly to obtain solid mixture A. 42g of sodium hydroxide is dissolved in 91.98g of water, and 135g of water glass is added to the sodium hydroxide solution to obtain an alkali activator. Solid mixture A is mixed with the alkali activator and stirred for 5 minutes to obtain mixture slurry B, which is then poured into a 30mm×30mm×30mm steel mold containing reinforcing bars. The slurry was poured into a cylindrical mold and continuously vibrated to expel air. The sample was sealed together with the mold and cured in an oven at 60°C for 6 hours. After demolding, it was cured at room temperature for 14 days.

[0132] The cured cubic specimens were used for compressive strength testing, and the cured cylindrical specimens with embedded steel bars were used for chloride salt resistance testing. The compressive strength test was carried out for 14 days on an integrated compression and flexural strength tester. The part of the cylindrical specimen with embedded steel bars exposed to air was sealed, and the rest was completely immersed in a 3.5wt% sodium chloride solution. A voltage of 1.5V was applied to accelerate corrosion. Electrochemical monitoring was carried out every 12 hours of acceleration, for a total of 240 hours. The steel bars began to corrode after 108 hours.

[0133] Comparative Example 9:

[0134] The chloride-resistant geopolymer concrete material in this comparative example includes solid powder, aggregate, and alkali activator; the solid powder contains 10 wt% fly ash and 90 wt% slag; the aggregate contains 100 wt% iron tailings. Solid sodium hydroxide and calcium carbide slag are used as alkali activators, with the solid sodium hydroxide content being 11 wt% of the solid powder and the calcium carbide slag content being 18.66 wt% of the solid powder, and the water-to-solid ratio being 0.6.

[0135] In preparation, 30g of fly ash and 270g of slag are weighed and mixed evenly to obtain solid powder. 600g of iron tailings are weighed and mixed evenly to obtain aggregate. The aggregate and solid powder are mixed evenly to obtain solid mixture A. 52.67g of calcium carbide slag is weighed and dissolved in 80g of water. 33g of sodium hydroxide is weighed and dissolved in 100g of water and left to stand for 24 hours. The sodium hydroxide solution is poured into the calcium carbide slag solution to obtain an alkali activator. The solid mixture A is mixed with the alkali activator and stirred for 5 minutes to obtain mixture slurry B. This slurry is poured into a 30mm×30mm×30mm steel mold containing reinforcing bars. The slurry was poured into a cylindrical mold and continuously vibrated to expel air. The sample was sealed together with the mold and cured in an oven at 60°C for 6 hours. After demolding, it was cured at room temperature for 14 days.

[0136] The cured cubic specimens were used for compressive strength testing, and the cured cylindrical specimens with embedded steel bars were used for chloride salt resistance testing. The compressive strength test was carried out for 14 days on an integrated compression and flexural strength testing machine. The part of the cylindrical specimen with embedded steel bars exposed to air was sealed, and the rest was completely immersed in a 3.5wt% sodium chloride solution. A voltage of 1.5V was applied to accelerate corrosion. Electrochemical monitoring was carried out every 12 hours of acceleration, for a total of 240 hours. The steel bars began to corrode after 132 hours.

[0137] Comparative Example 10:

[0138] The chloride-resistant geopolymer concrete material in this comparative example includes solid powder, aggregate, and alkali activator; the solid powder contains 10 wt% fly ash and 90 wt% slag; the aggregate contains 100 wt% iron tailings. Water glass and calcium carbide slag are used as alkali activators, with water glass accounting for 45 wt% of the solid powder and calcium carbide slag accounting for 14 wt%, and the water-to-solid ratio is 0.6.

[0139] In preparation, 30g of fly ash and 270g of slag are weighed and mixed evenly to obtain solid powder. 600g of iron tailings are weighed and mixed evenly to obtain aggregate. The aggregate and solid powder are mixed evenly to obtain solid mixture A. 42g of calcium carbide slag is weighed and dissolved in 91.98g of water. 135g of water glass is weighed and added to the calcium carbide slag solution to obtain an alkali activator. The solid mixture and alkali activator are mixed and stirred for 5 minutes to obtain mixture slurry B, which is poured into a 30mm×30mm×30mm steel mold containing reinforcing bars. The slurry was poured into a cylindrical mold and continuously vibrated to expel air. The sample was sealed together with the mold and cured in an oven at 60°C for 6 hours. After demolding, it was cured at room temperature for 14 days.

[0140] The cured cubic specimens were used for compressive strength testing, and the cured cylindrical specimens with embedded steel bars were used for chloride salt resistance testing. The compressive strength test was carried out for 14 days on an integrated compression and flexural strength testing machine. The part of the cylindrical specimen with embedded steel bars exposed to air was sealed, and the rest was completely immersed in a 3.5wt% sodium chloride solution. A voltage of 1.5V was applied to accelerate corrosion. Electrochemical monitoring was carried out every 12 hours of acceleration, for a total of 240 hours. The steel bars began to corrode after 120 hours.

[0141] Comparative Example 11:

[0142] The chloride-resistant geopolymer concrete material in this comparative example includes solid powder, aggregate, and alkali activator; the solid powder contains 10 wt% fly ash and 90 wt% slag; the aggregate contains 100 wt% iron tailings. Water glass and solid sodium hydroxide are used as alkali activators, with water glass accounting for 45 wt% of the solid powder and solid sodium hydroxide accounting for 14 wt%, resulting in a water-to-solid ratio of 0.6.

[0143] In preparation, 30g of fly ash and 270g of slag are weighed and mixed evenly to obtain solid powder. 600g of iron tailings are weighed and mixed evenly to obtain aggregate. The aggregate and solid powder are mixed evenly to obtain solid mixture A. 42g of sodium hydroxide is dissolved in 91.98g of water, and 135g of water glass is added to the sodium hydroxide solution to obtain an alkali activator. The solid mixture A and the alkali activator are mixed and stirred for 5 minutes to obtain mixture slurry B, which is poured into a 30mm×30mm×30mm steel mold containing reinforcing bars. The slurry was poured into a cylindrical mold and continuously vibrated to expel air. The sample was sealed together with the mold and cured in an oven at 60°C for 6 hours. After demolding, it was cured at room temperature for 14 days.

[0144] The cured cubic specimens were used for compressive strength testing, and the cured cylindrical specimens with embedded steel bars were used for chloride salt resistance testing. The compressive strength test was carried out for 14 days on an integrated compression and flexural strength tester. The part of the cylindrical specimen with embedded steel bars exposed to air was sealed, and the rest was completely immersed in a 3.5wt% sodium chloride solution. A voltage of 1.5V was applied to accelerate corrosion. Electrochemical monitoring was carried out every 12 hours of acceleration, for a total of 240 hours. The steel bars began to corrode after 108 hours.

[0145] Comparative Example 12:

[0146] The chloride-resistant geopolymer concrete material in this comparative example includes solid powder, aggregate, and alkali activator; the fly ash content in the solid powder is 100 wt%; the iron tailings content in the aggregate is 100 wt%. Solid sodium hydroxide and calcium carbide slag are used as alkali activators, with the solid sodium hydroxide content in the alkali activator being 11 wt% of the solid powder and the calcium carbide slag content being 18.66 wt% of the solid powder, and the water-to-solid ratio being 0.6.

[0147] In preparation, 300g of fly ash is weighed and stirred evenly to obtain solid powder, and 600g of iron tailings is weighed and stirred evenly to obtain aggregate. The aggregate and solid powder are mixed evenly to obtain solid mixture A. 55.98g of carbide slag is weighed and dissolved in 80g of water, and 33g of sodium hydroxide is weighed and dissolved in 100g of water. The solution is left to stand for 24 hours, and the sodium hydroxide solution is poured into the carbide slag solution to obtain an alkali activator. The solid mixture A is mixed with the alkali activator and stirred for 5 minutes to obtain mixture slurry B, which is then poured into a 30mm×30mm×30mm steel mold containing reinforcing bars. The slurry was poured into a cylindrical mold and continuously vibrated to expel air. The sample was sealed together with the mold and cured in an oven at 60°C for 6 hours. After demolding, it was cured at room temperature for 14 days.

[0148] The cured cubic specimens were used for compressive strength testing, and the cured cylindrical specimens with embedded steel bars were used for chloride salt resistance testing. The compressive strength test was carried out for 14 days on an integrated compression and flexural strength testing machine. The part of the cylindrical specimen with embedded steel bars exposed to air was sealed, and the rest was completely immersed in a 3.5wt% sodium chloride solution. A voltage of 1.5V was applied to accelerate corrosion. Electrochemical monitoring was carried out every 12 hours of acceleration, for a total of 240 hours. The steel bars began to corrode after 132 hours.

[0149] Comparative Example 13:

[0150] The chloride-resistant geopolymer concrete material in this comparative example includes solid powder, aggregate, and alkali activator; the fly ash content in the solid powder is 100 wt%; the iron tailings content in the aggregate is 100 wt%. Water glass and calcium carbide slag are used as alkali activators, with the water glass content in the alkali activator being 45 wt% of the solid powder mass and the calcium carbide slag content being 14 wt% of the solid powder mass, and the water-to-solid ratio being 0.6.

[0151] In preparation, 300g of fly ash is weighed and stirred evenly to obtain solid powder, and 600g of iron tailings is weighed and stirred evenly to obtain aggregate. The aggregate and solid powder are mixed evenly to obtain solid mixture A. 42g of calcium carbide slag is weighed and dissolved in 91.98g of water, and 135g of water glass is weighed and added to the calcium carbide slag solution to obtain alkali activator. The solid mixture A is mixed with alkali activator C and stirred for 5 minutes to obtain mixture slurry B, which is poured into a 30mm×30mm×30mm steel mold containing reinforcing bars. The slurry was poured into a cylindrical mold and continuously vibrated to expel air. The sample was sealed together with the mold and cured in an oven at 60°C for 6 hours. After demolding, it was cured at room temperature for 14 days.

[0152] The cured cubic specimens were used for compressive strength testing, and the cured cylindrical specimens with embedded steel bars were used for chloride salt resistance testing. The compressive strength test was carried out for 14 days on an integrated compression and flexural strength testing machine. The part of the cylindrical specimen with embedded steel bars exposed to air was sealed, and the rest was completely immersed in a 3.5wt% sodium chloride solution. A voltage of 1.5V was applied to accelerate corrosion. Electrochemical monitoring was carried out every 12 hours of acceleration, for a total of 240 hours. The steel bars began to corrode after 132 hours.

[0153] Comparative Example 14:

[0154] The chloride-resistant geopolymer concrete material in this comparative example includes solid powder, aggregate, and alkali activator; the fly ash content in the solid powder is 100 wt%; the iron tailings content in the aggregate is 100 wt%. Water glass and solid sodium hydroxide are used as alkali activators, with the water glass content in the alkali activator being 45 wt% of the solid powder and the solid sodium hydroxide content being 14 wt% of the solid powder, and the water-to-solid ratio being 0.6.

[0155] In preparation, 300g of fly ash is weighed and stirred evenly to obtain solid powder, and 600g of iron tailings is weighed and stirred evenly to obtain aggregate. The aggregate and solid powder are mixed evenly to obtain solid mixture A. 42g of sodium hydroxide is weighed and dissolved in 91.98g of water, and 135g of water glass is weighed and added to the sodium hydroxide solution to obtain an alkali activator. The solid mixture A and the alkali activator are mixed and stirred for 5 minutes to obtain a slurry B, which is then poured into a 30mm×30mm×30mm steel mold containing reinforcing bars. The slurry was poured into a cylindrical mold and continuously vibrated to expel air. The sample was sealed together with the mold and cured in an oven at 60°C for 6 hours. After demolding, it was cured at room temperature for 14 days.

[0156] The cured cubic specimens were used for compressive strength testing, and the cured cylindrical specimens with embedded steel bars were used for chloride salt resistance testing. The compressive strength test was carried out for 14 days on an integrated compression and flexural strength tester. The part of the cylindrical specimen with embedded steel bars exposed to air was sealed, and the rest was completely immersed in a 3.5wt% sodium chloride solution. A voltage of 1.5V was applied to accelerate corrosion. Electrochemical monitoring was carried out every 12 hours of acceleration, for a total of 240 hours. The steel bars began to corrode after 96 hours.

[0157] Comparative Example 15:

[0158] The chloride-resistant geopolymer concrete material in this comparative example includes solid powder, aggregate, and alkali activator; the solid powder contains 10 wt% fly ash and 90 wt% slag; the aggregate contains 20 wt% iron tailings and 80 wt% fine sand. Calcium carbide slag, as the alkali activator, accounts for 29.66 wt% of the solid powder, and the water-to-solid ratio is 0.6.

[0159] In preparation, 30g of fly ash and 270g of slag are weighed and mixed evenly to obtain solid powder. 120g of iron tailings and 480g of fine sand are weighed and mixed evenly to obtain aggregate. The aggregate and solid powder are mixed evenly to obtain solid mixture A. 88.98g of calcium carbide slag is weighed and dissolved in 180g of water. The solid mixture A is mixed with an alkali activator and stirred for 5 minutes to obtain mixture slurry B. This slurry is poured into a 30mm×30mm×30mm steel mold containing reinforcing bars. The slurry was poured into a cylindrical mold and continuously vibrated to expel air. The sample was sealed together with the mold and cured in an oven at 60°C for 6 hours. After demolding, it was cured at room temperature for 14 days.

[0160] The cured cubic specimens were used for compressive strength testing, and the cured cylindrical specimens with embedded steel bars were used for chloride salt resistance testing. The compressive strength test was carried out for 14 days on an integrated compression and flexural strength testing machine. The part of the cylindrical specimen with embedded steel bars exposed to air was sealed, and the rest was completely immersed in a 3.5wt% sodium chloride solution. A voltage of 1.5V was applied to accelerate corrosion. Electrochemical monitoring was carried out every 12 hours of acceleration, for a total of 240 hours. The steel bars began to corrode after 120 hours.

[0161] Comparative Example 16:

[0162] The chloride-resistant geopolymer concrete material in this comparative example includes solid powder, aggregate, and alkali activator; the solid powder contains 10 wt% fly ash and 90 wt% slag; the aggregate contains 20 wt% iron tailings and 80 wt% fine sand. Solid sodium hydroxide, as the alkali activator, accounts for 29.66 wt% of the solid powder, and the water-to-solid ratio is 0.6.

[0163] In preparation, 30g of fly ash and 270g of slag are weighed and mixed evenly to obtain solid powder. 120g of iron tailings and 480g of fine sand are weighed and mixed evenly to obtain aggregate. The aggregate and solid powder are mixed evenly to obtain solid mixture A. 88.98g of sodium hydroxide is dissolved in 180g of water. Solid mixture A is mixed with an alkali activator and stirred for 5 minutes to obtain mixture slurry B. This slurry is poured into a 30mm×30mm×30mm steel mold containing reinforcing bars. The slurry was poured into a cylindrical mold and continuously vibrated to expel air. The sample was sealed together with the mold and cured in an oven at 60°C for 6 hours. After demolding, it was cured at room temperature for 14 days.

[0164] The cured cubic specimens were used for compressive strength testing, and the cured cylindrical specimens with embedded steel bars were used for chloride salt resistance testing. The compressive strength test was carried out for 14 days on an integrated compression and flexural strength tester. The part of the cylindrical specimen with embedded steel bars exposed to air was sealed, and the rest was completely immersed in a 3.5wt% sodium chloride solution. A voltage of 1.5V was applied to accelerate corrosion. Electrochemical monitoring was carried out every 12 hours of acceleration, for a total of 240 hours. The steel bars began to corrode after 144 hours.

[0165] The mechanical properties of the chloride-resistant geopolymer concretes prepared in Examples 1-16 were tested, and the results are shown in Table 2.

[0166] Table 2 shows the test results of the mechanical properties of the chloride-resistant geopolymers obtained from Comparative Examples 1-16.

[0167]

[0168] As shown in Table 2, the 14-day compressive strength of the chloride-resistant geopolymer concrete prepared in each comparative example was significantly lower than that in the example, and the corrosion initiation time was within 150 hours. This indicates that the lack of the components of the present invention significantly reduced the compressive strength and chloride-resistant effect of the geopolymer. This shows that the components of the present invention have a corresponding synergistic effect, jointly improving the chloride-resistant effect and having excellent prospects for promotion and application.

[0169] In summary, this invention discloses a multi-solid waste-based chloride-resistant geopolymer concrete material and its preparation method. This chloride-resistant geopolymer consists of solid powder, aggregate, and an alkali activator. The solid powder is composed of fly ash and blast furnace slag, the aggregate is iron tailings and fine sand, and the alkali activator is a mixture of solid sodium hydroxide, carbide slag, water glass, and water. This invention uses fly ash, blast furnace slag, iron tailings, and fine sand as main raw materials, and through mixing with an alkali activator, obtains a novel chloride-resistant concrete material. Its process is simple, produces no CO2 emissions, and exhibits good mechanical properties, meeting the requirements of general marine engineering concrete construction. It also realizes the resource utilization of fly ash and blast furnace slag, effectively solving the environmental pollution problems caused by fly ash and slag storage, and has good application prospects.

[0170] The various embodiments of the present invention have now been described. The above description is exemplary and not exhaustive, nor is it limited to the described embodiments. Many modifications and variations will be included within the scope and spirit of the described embodiments by those skilled in the art without departing from the scope and spirit of the invention.

Claims

1. A multi-solid waste-based chloride-resistant geopolymer concrete material, characterized in that, Including the following raw materials: Solid powders, aggregates, and alkali activators: The solid powder consists of 10wt%~50wt% fly ash and 50wt%~90wt% slag; The aggregate consists of iron tailings and fine sand, with a total usage of 2 to 2.5 times the mass of the solid powder. The iron tailings content is 20 wt% to 60 wt%, and the fine sand content is 40 wt% to 80 wt%, with a total mass fraction of 100 wt%. The alkaline activator is a mixture of sodium hydroxide, carbide slag, water glass, and water; the amount of water glass is 30% to 45% of the solid powder mass, the amount of carbide slag is 1% to 5% of the solid powder mass, the amount of solid sodium hydroxide is 7.5% to 11% of the solid powder mass, and the mass ratio of water to solid powder is 0.6 to 0.

65. Based on a total weight percentage of 100%, the mass percentages of each component in the iron tailings are as follows: SiO2 30%~50%, Al2O3 10%~20%, Fe2O3 20%~30%, CaO 5%~10%, MgO 1%~3%, K2O 1%~3%, Na2O 1%~3%, TiO2 1%~2%, MnO 0.1%~0.5%, and its loss on ignition is 0.4%~1%. Based on a total weight percentage of 100%, the mass percentages of each component in the fine sand are as follows: SiO2 80%~90%, Al2O3 5%~10%, Na2O 0.1%~0.5%, K2O 1%~5%, Fe2O3 1%~5%, and its loss on ignition is 0.5%~1%. The particle size of the fly ash and slag is less than 0.075 mm, and the particle size of the fine sand and iron tailings is less than 0.5 mm.

2. The multi-solid waste-based chloride-resistant geopolymer concrete material as described in claim 1, characterized in that, Based on a total weight percentage of 100%, the mass percentages of each component in the fly ash are as follows: SiO2 50%~60%, Al2O3 25%~30%, Fe2O3 10%~20%, CaO 0.01%~0.05%, MgO 0.01%~0.08%, K2O 1%~3%, Na2O 0.01%~0.03%, TiO2 1%~3%, and its loss on ignition is 0.5%~1%.

3. The multi-solid waste-based chloride-resistant geopolymer concrete material as described in claim 1, characterized in that, Based on a total weight percentage of 100%, the mass percentages of each component in the slag are as follows: SiO2 25%~40%, Al2O3 5%~20%, Fe2O3 0.1%~1%, CaO 30%~50%, MgO 1%~3%, TiO2 1%~2%, Na2O 0.1%~1%, K2O 0.1%~0.5%, and its loss on ignition is 1%~5%.

4. The multi-solid waste-based chloride-resistant geopolymer concrete material as described in claim 1, characterized in that, The solution modulus of the alkali activator is 0.8 to 1.5; the water glass has a modulus of 3.3, a solid content of 34%, and a Baumé degree of 40.

5. The method for preparing the multi-solid waste-based chloride-resistant geopolymer concrete material according to any one of claims 1-4, characterized in that, Specifically, the steps include the following: Step S1: Mix fly ash, slag, iron tailings and fine sand in proportion to obtain solid mixture A; Step S2: Dissolve solid sodium hydroxide and carbide slag in water, add water glass, stir and mix well, and let stand for 2 hours to obtain an alkaline activator; Step S3: Mix the solid powder A obtained in step S1 with the alkali activator obtained in step S2, and then mechanically stir to obtain a mixed slurry B; Step S4: Pour the mixed slurry B into the steel mold and the columnar mold with embedded steel bars, and continuously vibrate to remove air from the slurry; Step S5: Seal the sample together with the mold, cure it at a certain curing temperature and time, and cure it at room temperature after demolding.

6. The method for preparing a multi-solid waste-based chloride-resistant geopolymer concrete material as described in claim 5, characterized in that, The mechanical stirring time in step S3 is 4-8 minutes.

7. The method for preparing a multi-solid waste-based chloride-resistant geopolymer concrete material as described in claim 5, characterized in that, In step S5, the curing temperature is 60~90℃ and the curing time is 6~12 h; the curing time at room temperature is 14~28 days.

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