Preparation method of alkali-activated porous geopolymer wall material by using recycled fine aggregate loaded enhancer

Abstract

The invention discloses a preparation method of an alkali-activated porous geopolymer wall material by using recycled fine aggregate to load an enhancer. The alkali-activated porous geopolymer wall material is prepared from the recycled fine aggregate, the enhancer, a cementing material, an alkali activator, a foaming agent and a water reducing agent. According to the method, slow-release carbonization strengthening of a porous geopolymer which takes water granulated slag and fly ash as binding materials, sodium hydroxide and water glass as alkali activators and hydrogen peroxide as a foaming agent is realized by utilizing a water-absorbing loading enhancer of recycled fine aggregate, so that the wall material with excellent performance is prepared; high-value utilization of building and industrial solid waste and low-carbon building wall manufacturing are achieved, and the problems that due to high water absorption and low hardness of recycled fine aggregate, the pore structure of an alkali-activated porous geopolymer wall material is distorted, the compressive strength is reduced, and an existing recycled fine aggregate strengthening technology has adaptability defects are solved.

Description

Technical Field

[0001] This invention belongs to the field of building materials technology and relates to a method for preparing wall materials, specifically a method for preparing porous geopolymer wall materials by using recycled fine aggregate loaded with carbonizing agent in conjunction with the alkaline-activated reaction of water slag-fly ash. Background Technology

[0002] As a core sector of global resource consumption and carbon emissions, the construction industry faces severe challenges to sustainable development. Construction demolition waste constitutes a huge proportion of the total, and traditional landfill disposal methods have significant drawbacks. Against this backdrop, autoclaved aerated concrete (AAC), with its lightweight, insulating, and low-carbon properties, is considered an important option for green buildings. However, the rise of foldable prefabricated buildings has placed more stringent multi-dimensional performance requirements on wall materials: not only do they need extreme lightweight and high strength to support multiple folding and unfolding operations of modules and reduce transportation and hoisting energy consumption, but they also need excellent dimensional stability to ensure precise fit and long-term airtightness of folding hinge joints. Simultaneously, materials must have rapid industrial production capabilities to meet the high-efficiency pace of prefabricated construction. Unfortunately, traditional AAC production models suffer from insurmountable resource and environmental bottlenecks, limiting its application in high-end foldable prefabricated buildings. The core problem lies in the heavy reliance on high-purity silica sand (SiO2≥80%) or fly ash as siliceous raw materials. Quartz sand grinding consumes a huge amount of energy, and high-quality resources are becoming increasingly scarce; although fly ash is a solid waste, its active SiO2 content is low and fluctuates greatly, which directly leads to uneven strength and excessive drying shrinkage of AAC products, making it difficult to consistently meet the stringent requirements of folding assembly systems for component precision and durability.

[0003] To address resource constraints and respond to the call for solid waste utilization, the industry has attempted to introduce recycled fine aggregate (RFA) as a substitute for siliceous materials. However, the inherent high water absorption and low hardness of RFA have become fatal weaknesses in its application in AAC. High water absorption interferes with the slurry hydration process, while low hardness exacerbates particle breakage under the high temperature and pressure of autoclaving. Together, these factors cause severe distortion of the internal pore structure of AAC, resulting in a significant decrease in its key mechanical property—compressive strength—by more than 30%, failing to meet the GB / T 11968-2020 superior grade standard (≥3.5 MPa). This strength loss and potential inhomogeneity make traditional AAC-RFA composite materials extremely risky when subjected to repeated bending stress, shear stress, and concentrated loads at joints during folding and assembly, bleakening its application prospects.

[0004] Existing strengthening technologies for RFA (Reinforced Plastic Aerated Concrete) exhibit significant compatibility issues when faced with the unique performance requirements and production rhythm of foldable prefabricated wall materials. Mechanical grinding, while reducing water absorption, damages the valuable active CaO component in the old mortar layer on the RFA surface. This CaO is an indispensable calcium source for the AAC (Alternating Current Acrylic Aerated Concrete) hydration reaction, further weakening the material's strength. Acid immersion, while improving hardness, generates heavy metal-containing waste liquid, severely contradicting the environmental principle of solid waste resource utilization. Carbonization strengthening technologies (dry / wet / pressurized methods) can effectively improve RFA performance by reacting Ca(OH)2 with CO2 to generate CaCO3, but their process requires maintaining a reaction temperature of 60°C and takes over 12 hours, heavily relying on external CO2 gas sources and delivery systems. These high-energy-consumption, long-cycle, and externally dependent carbon characteristics are incompatible with the inherent high-temperature saturated steam autoclaving system of AAC production lines and the rapid, continuous, and industrialized production rhythm pursued by foldable prefabricated buildings, making large-scale application difficult.

[0005] Of particular note is that bulk industrial solid wastes—slag and fly ash—not only possess enormous resource potential, but their specific chemical composition also offers a unique opportunity to overcome the aforementioned challenges. Slag is rich in CaO and SiO2, while fly ash is rich in SiO2 and Al2O3; together, they constitute a high-quality source of silicon, aluminum, and calcium. Through an alkali-activated reaction, they can efficiently generate geopolymer gels. This novel cementitious material system exhibits revolutionary advantages: its production process reduces carbon emissions by more than 80% compared to traditional cement-based materials, and utilizing 1 ton of slag-fly ash mixture can reduce CO2 emissions by approximately 0.8 tons, aligning with the deep decarbonization needs of the construction industry. More importantly, geopolymers possess characteristics such as rapid hardening and early strength, good volume stability (low drying shrinkage), high temperature resistance, and high interfacial bonding strength, perfectly meeting the core requirements of folded prefabricated walls for rapid demolding and turnover, high dimensional accuracy, excellent joint connection strength, and resistance to folding stress. Crucially, the highly active CaO component in the slag can effectively compensate for the loss of surface calcium source caused by grinding or original defects in RFA, providing sufficient calcium ions for the system to participate in the reaction. At the same time, the abundant glass microspheres in fly ash can play a "ball effect" in the freshly mixed slurry to improve fluidity and optimize the aggregate-slurry interface transition zone (ITZ) in the hardened body, significantly improving the integrity, density and mechanical properties of the composite material, fundamentally solving the performance shortcomings of RFA in lightweight porous materials.

[0006] Therefore, developing a new type of porous lightweight wall material with water slag-fly ash geopolymer as the cementing matrix and reinforced RFA as the lightweight aggregate has become a key path to break through the bottleneck in the development of wall materials for folding prefabricated buildings. Summary of the Invention

[0007] To address the issues of pore structure distortion and decreased compressive strength in alkali-activated porous geopolymer wall materials caused by the high water absorption and low hardness of recycled fine aggregates, as well as the compatibility limitations of existing recycled fine aggregate strengthening technologies, this invention provides a method for preparing alkali-activated porous geopolymer wall materials using recycled fine aggregates loaded with a reinforcing agent. This method utilizes the water-absorbing properties of recycled fine aggregates to load a reinforcing agent, achieving slow-release carbonization strengthening of porous geopolymers using slag and fly ash as cementing materials, sodium hydroxide and water glass as alkali activators, and hydrogen peroxide as a foaming agent. This results in the preparation of high-performance wall materials, realizing the high-value utilization of construction and industrial solid waste and the manufacture of low-carbon building walls.

[0008] The objective of this invention is achieved through the following technical solution:

[0009] An alkali-activated porous geopolymer wall material utilizing recycled fine aggregate loaded with a reinforcing agent is prepared from recycled fine aggregate, a reinforcing agent, a cementitious material, an alkali activator, a foaming agent, and a water-reducing agent, wherein:

[0010] The reinforcing agent is a carbonate or bicarbonate, and the mass of the reinforcing agent accounts for 87-95% of the saturated water absorption rate of the recycled fine aggregate;

[0011] The cementing material is water slag and fly ash, and the mass ratio of water slag to fly ash is 5:5 to 6:4, preferably 6:4;

[0012] The mass ratio (mortar-cement ratio) of the cementitious material to the recycled fine aggregate is 1:2;

[0013] The alkaline activator is sodium hydroxide and water glass, with an alkaline activator modulus of 1.2 to 1.4 and an alkaline content of 5% to 8%.

[0014] The foaming agent is hydrogen peroxide, and the dosage is 0.25~0.6% of the total mass of the cementitious material;

[0015] The water-reducing agent is a naphthalene-based water-reducing agent, and the dosage is 0.1~0.3% of the total mass of water slag and fly ash.

[0016] A method for preparing alkali-activated porous geopolymer wall material using recycled fine aggregate loaded with a reinforcing agent includes the following steps:

[0017] Step S1: Based on the saturated surface-dry water absorption rate of the recycled fine aggregate and the water-cement ratio of the recycled mortar, weigh the reinforcing agent solution, mix it evenly with the recycled fine aggregate, and let it stand for 5-14 hours to obtain pretreated aggregate, wherein the mass concentration of the reinforcing agent solution is 5-20%.

[0018] Step S2: Mix the pretreated aggregate, water slag and fly ash, add water reducing agent, and stir slowly for 1-5 minutes;

[0019] Step S3: Mix the foaming agent and alkali activator, pour them into the mixing pot of step S2, and mix the liquid and powder thoroughly. Then add water to adjust the water-cement ratio to 0.55~0.6.

[0020] Step S4: Pour the slurry obtained in step S3 into the mold, vibrate to remove air bubbles, cover with plastic wrap, and place in a drying oven for curing for 6-10 hours.

[0021] Step S5: Take out the gas-generating mortar obtained in step S4 and saw off the loose part formed on the top of the mortar due to gas accumulation during the gas generation process.

[0022] Step S6: Place the gas-generating mortar obtained in step S5 into a drying oven for continued curing. After 20-30 hours, remove it from the mold and place it in a room temperature environment for curing until 7 days.

[0023] Compared with the prior art, the present invention has the following advantages:

[0024] 1. By utilizing the high water absorption properties of recycled fine aggregate (RFA) and loading it with carbonate reinforcing agents (such as sodium carbonate, sodium bicarbonate, or potassium carbonate solutions), slow-release carbonation strengthening of the recycled mortar is achieved during subsequent preparation. This method eliminates the need for energy-intensive external CO2 delivery systems and prolonged high-temperature reactions. It cleverly utilizes the material's inherent properties to generate calcium carbonate crystals in situ on the old mortar layer on the RFA surface during the static curing stage. This effectively fills the interfacial micropores, increasing the microhardness of the interfacial transition zone by 20-30%, significantly improving the pore structure distortion and compressive strength reduction problems caused by the high water absorption and low hardness of RFA.

[0025] 2. An alkali-activated geopolymer system using slag-fly ash as a cementing material achieves a complete solid waste cementing system, significantly reducing carbon emissions (more than 80% lower than cement-based materials). This system, combined with slag (which provides ample Ca2+), further enhances the effectiveness of the cementing material. 2+ By combining a precise ratio of SiO2 and fly ash (supplementing SiO2 and Al2O3) (mass ratio 60:40) with optimized alkali activation parameters (modulus 1.4, alkali content 5%), and synergistically enhancing the effect of RFA, a lightweight, high-strength, porous geopolymer wall material with a dry density of 1000~1400 kg / m³ and a compressive strength of 2~9 MPa was successfully prepared. This material not only achieves high-value utilization of construction and industrial solid waste but also meets the performance requirements of engineering applications. Attached Figure Description

[0026] Figure 1 A flowchart of a method for preparing alkali-activated porous geopolymer wall material using recycled fine aggregate loaded with reinforcing agent;

[0027] Figure 2 Comparison of the interface transition zone before and after strengthening with recycled fine aggregate. Detailed Implementation

[0028] The technical solution of the present invention will be further described below with reference to the accompanying drawings, but it is not limited thereto. Any modifications or equivalent substitutions to the technical solution of the present invention that do not depart from the spirit and scope of the technical solution of the present invention should be covered within the protection scope of the present invention.

[0029] This invention provides an alkali-activated porous geopolymer wall material using recycled fine aggregate loaded with a reinforcing agent. The wall material is prepared from recycled fine aggregate, a reinforcing agent, a cementitious material, an alkali activator, a foaming agent, and a water-reducing agent. The reinforcing agent is a carbonate or bicarbonate, and its mass accounts for 87-95% of the saturated water absorption rate of the recycled fine aggregate. The cementitious material is slag or fly ash. The mass ratio of ash, slag, and fly ash is 5:5 to 6:4, preferably 6:4; the mass ratio (mortar-cement ratio) of the cementitious material to recycled fine aggregate is 1:2; the alkali activator is sodium hydroxide and water glass, with an alkali activator modulus of 1.2 to 1.4 and an alkali content of 5 to 8%; the foaming agent is hydrogen peroxide, with an admixture dosage of 0.25 to 0.6% of the total mass of the cementitious material; the water-reducing agent is a naphthalene-based water-reducing agent, with an admixture dosage of 0.1 to 0.3% of the total mass of slag and fly ash. Figure 1 As shown, the specific preparation method is as follows:

[0030] Step S1: Prepare a reinforcing agent solution with a mass concentration of 5-20%, wherein the reinforcing agent solution is a carbonate solution or a bicarbonate solution, such as sodium carbonate solution, potassium carbonate solution, sodium bicarbonate solution, etc.

[0031] Step S2: Based on the saturated surface-dry water absorption rate of the recycled fine aggregate and the water-cement ratio of the recycled mortar, weigh a certain mass of reinforcing agent solution according to the water absorption amount, mix it evenly with the recycled fine aggregate, and let it stand for 5-14 hours to obtain pretreated aggregate. The particle size distribution of the recycled fine aggregate is as follows: 45-55% of the particles are 0.15-1.5 mm, 35-45% are 1.0-3.0 mm, and 5-15% are 3.0-4.75 mm. The mass ratio of recycled fine aggregate to reinforcing agent is determined according to the water absorption characteristics of the recycled fine aggregate and the water-cement ratio of the recycled mortar used, and the mass of reinforcing agent is controlled to account for 87-95% of the saturated water absorption rate of the recycled fine aggregate.

[0032] Step S3: Mix the pretreated aggregate, water slag, and fly ash, add the water-reducing agent, and stir slowly for 1-5 minutes. The water slag contains 35.14% CaO, 28.18% SiO2, and 15.61% Al2O3 (mass fraction), while the fly ash contains 31.23% SiO2, 1.25% CaO, and 19.48% Al2O3 (mass fraction). The dosage of the naphthalene-based water-reducing agent is adjusted according to the initial fluidity requirement of the slurry to ensure an initial fluidity of 170-200 mm. The dosage is typically 0.1-0.3% of the total mass of the cementitious materials. The mass ratio of water slag to fly ash in the cementitious material system is 5:5 to 6:4. This ratio allows for the full utilization of their synergistic effect—the water slag provides sufficient CaO... 2+ To promote early gel formation, fly ash is used to supplement SiO2 and Al2O3 to optimize the three-dimensional network structure, enabling the material to achieve a 28-day compressive strength of 8~12MPa.

[0033] Step S4: Mix the weighed H2O2 with the alkali activator and stir appropriately with a stirrer. The alkali activator is a mixture of sodium hydroxide and water glass in a certain proportion, wherein the ratio of n(SiO2) / n(Na2O) (alkali activator modulus) is controlled at 1.2~1.4, and the alkali content (based on the proportion of Na2O mass to the total mass of cementitious material) is 5~8%. H2O2 is used as a foaming agent, and its dosage is 0.25~0.6% of the total mass of water slag and fly ash. It is used to introduce pores to reduce the density of the material and give it a porous structure.

[0034] Step S5: Pour the mixture obtained in step S4 into a mixing pot while stirring. During the stirring process, stir slowly for 1 to 5 minutes, then stir quickly for 5 to 15 seconds to fully mix the liquid and powder. Then add water to adjust the water-cement ratio (the ratio of water to the total mass of cementitious materials) to 0.55 to 0.6 to balance the fluidity of the slurry and the mechanical properties after hardening.

[0035] Step S6: Pour the slurry obtained in step S5 into the mold, vibrate for 20-40 seconds to remove air bubbles, cover with plastic wrap, and place in an electric heating drying oven at 40-50℃ for 6-10 hours. Vibration is performed using a 30Hz vibration table to ensure that air bubbles in the slurry are fully expelled and to avoid local strength defects caused by air bubble accumulation.

[0036] Step S7: Take out the gas-generating mortar obtained in step S6 and saw off the "bread head" generated by gas generation. The "bread head" is the loose part formed on the top of the mortar due to gas accumulation during the gas generation process. After sawing it off, the uniformity of the performance of the test block can be ensured.

[0037] Step S8: Place the gas-generating mortar obtained in step S7 into an electric heating drying oven at 40~50℃ for further curing. After 20~30 hours, remove it from the mold and place it in a room temperature environment for curing until 7 days.

[0038] Example 1:

[0039] This embodiment provides a method for preparing alkali-activated porous geopolymer wall materials using recycled fine aggregate loaded with reinforcing agents, such as... Figure 1 As shown, the method includes the following steps:

[0040] Step S1: Prepare a sodium carbonate solution with a mass concentration of 10%.

[0041] Step S2: Weigh the sodium carbonate solution and mix it evenly with the recycled fine aggregate, then let it stand for 8 hours with moisture to obtain pretreated aggregate, wherein the mass of sodium carbonate accounts for 90% of the saturated water absorption rate of the recycled fine aggregate.

[0042] Comparison of the strengthening of the interface transition zone of recycled fine aggregate before and after Figure 2 As shown. By Figure 2 It can be seen that after the recycled fine aggregate is pretreated with a reinforcing agent, the old mortar layer on its surface reacts with the reinforcing agent to generate calcium carbonate crystals, which can fill the micropores at the interface, improve the bonding strength between the recycled fine aggregate and the geopolymer gel, and increase the microhardness of the interface transition zone by 20-30% compared with the untreated group.

[0043] Step S3: Mix the pretreated aggregate, water slag, and fly ash, add naphthalene-based water-reducing agent, and stir slowly for 2 minutes. The dosage of naphthalene-based water-reducing agent is 0.103% of the total mass of cementitious materials. The mass ratio of water slag to fly ash in the cementitious material system is 6:4, the dosage of water slag is 60% of the total mass of cementitious materials, the dosage of fly ash is 40% of the total mass of cementitious materials, and the binder-sand ratio is 1:2.

[0044] Step S4: Mix the weighed H2O2 with an alkali activator with an alkali activation modulus of 1.4 and an alkali content of 5%, and stir appropriately with a stirrer. The amount of H2O2 added is 0.25% of the total mass of water slag and fly ash.

[0045] Step S5: Pour the mixture obtained in step S4 into the mixing pot while stirring. During the stirring process, stir slowly for 3 minutes and then stir quickly for 10 seconds to fully mix the liquid and powder. Then add water to adjust the water-cement ratio to 0.55 to balance the fluidity of the slurry and the mechanical properties after hardening.

[0046] Step S6: Vibrate the mixture at 30Hz for 30 seconds to remove air bubbles, cover with plastic wrap, and place in an electric heating drying oven at 40℃ for 8 hours.

[0047] Step S7: Take out the gas-generating mortar obtained in step S6 and saw off the "bread head" generated by gas generation. The "bread head" is the loose part formed on the top of the mortar due to gas accumulation during the gas generation process. After sawing it off, the uniformity of the performance of the test block can be ensured.

[0048] Step S8: Place the gas-generating mortar obtained in step S7 into an electric heating blast drying oven for further curing. After 24 hours, remove it from the mold and place it in a room temperature environment for curing for 7 days. The obtained porous geopolymer has a compressive strength of 8.3 MPa and a dry density of 1396.0.

[0049] Example 2:

[0050] This embodiment provides a method for preparing alkali-activated porous geopolymer wall materials using recycled fine aggregate loaded with reinforcing agents, such as... Figure 1 As shown, the method includes the following steps:

[0051] Step S1: Prepare a sodium carbonate solution with a mass concentration of 10%.

[0052] Step S2: Weigh the sodium carbonate solution and mix it evenly with the recycled fine aggregate, then let it stand for 8 hours with moisture to obtain pretreated aggregate, wherein the mass of sodium carbonate accounts for 90% of the saturated water absorption rate of the recycled fine aggregate.

[0053] Step S3: Mix the pretreated aggregate, water slag, and fly ash, add naphthalene-based water-reducing agent, and stir slowly for 2 minutes. The dosage of naphthalene-based water-reducing agent is 0.103% of the total mass of cementitious materials. The mass ratio of water slag to fly ash in the cementitious material system is 6:4, the dosage of water slag is 60% of the total mass of cementitious materials, the dosage of fly ash is 40% of the total mass of cementitious materials, and the binder-sand ratio is 1:2.

[0054] Step S4: Mix the weighed H2O2 with an alkali activator with an alkali activation modulus of 1.4 and an alkali content of 5%, and stir appropriately with a stirrer. The amount of H2O2 added is 0.40% of the total mass of water slag and fly ash.

[0055] Step S5: Pour the mixture obtained in step S4 into the mixing pot while stirring. During the stirring process, stir slowly for 3 minutes and then stir quickly for 10 seconds to fully mix the liquid and powder. Then add water to adjust the water-cement ratio to 0.55 to balance the fluidity of the slurry and the mechanical properties after hardening.

[0056] Step S6: Vibrate the mixture at 30Hz for 30 seconds to remove air bubbles, cover with plastic wrap, and place in an electric heating drying oven at 40℃ for 8 hours.

[0057] Step S7: Take out the gas-generating mortar obtained in step S6 and saw off the "bread head" generated by gas generation. The "bread head" is the loose part formed on the top of the mortar due to gas accumulation during the gas generation process. After sawing it off, the uniformity of the performance of the test block can be ensured.

[0058] Step S8: Place the gas-generating mortar obtained in step S7 into an electric heating blast drying oven for further curing. After 24 hours, remove it from the mold and allow it to cure at room temperature for 7 days. The obtained porous geopolymer has a compressive strength of 5.7 MPa and a dry density of 1179.3.

[0059] Example 3:

[0060] This embodiment provides a method for preparing alkali-activated porous geopolymer wall materials using recycled fine aggregate loaded with reinforcing agents, such as... Figure 1 As shown, the method includes the following steps:

[0061] Step S1: Prepare a sodium carbonate solution with a mass concentration of 10%.

[0062] Step S2: Weigh the sodium carbonate solution and mix it evenly with the recycled fine aggregate, then let it stand for 8 hours with moisture to obtain pretreated aggregate, wherein the mass of sodium carbonate accounts for 90% of the saturated water absorption rate of the recycled fine aggregate.

[0063] Step S3: Mix the pretreated aggregate, water slag, and fly ash, add naphthalene-based water-reducing agent, and stir slowly for 2 minutes. The dosage of naphthalene-based water-reducing agent is 0.103% of the total mass of cementitious materials. The mass ratio of water slag to fly ash in the cementitious material system is 6:4, the dosage of water slag is 60% of the total mass of cementitious materials, the dosage of fly ash is 40% of the total mass of cementitious materials, and the binder-sand ratio is 1:2.

[0064] Step S4: Mix the weighed H2O2 with an alkali activator with an alkali activation modulus of 1.4 and an alkali content of 5%, and stir appropriately with a stirrer. The amount of H2O2 is 0.50% of the total mass of water slag and fly ash.

[0065] Step S5: Pour the mixture obtained in step S4 into the mixing pot while stirring. During the stirring process, stir slowly for 3 minutes and then stir quickly for 10 seconds to fully mix the liquid and powder. Then add water to adjust the water-cement ratio to 0.55 to balance the fluidity of the slurry and the mechanical properties after hardening.

[0066] Step S6: Vibrate the mixture at 30Hz for 30 seconds to remove air bubbles, cover with plastic wrap, and place in an electric heating drying oven at 40℃ for 8 hours.

[0067] Step S7: Take out the gas-generating mortar obtained in step S6 and saw off the "bread head" generated by gas generation. The "bread head" is the loose part formed on the top of the mortar due to gas accumulation during the gas generation process. After sawing it off, the uniformity of the performance of the test block can be ensured.

[0068] Step S8: Place the gas-generating mortar obtained in step S7 into an electric heating blast drying oven for further curing. After 24 hours, remove it from the mold and allow it to cure at room temperature for 7 days. The obtained porous geopolymer has a compressive strength of 2.6 MPa and a dry density of 1035.7.

[0069] Example 4:

[0070] The difference between this embodiment and embodiments 1-3 is that the reinforcing agent solution is a sodium bicarbonate solution, the fly ash content is 50%, the water slag content is 50%, the water-ash ratio is 0.6, and the water-reducing agent content is 0.2%.

[0071] Example 5:

[0072] The difference between this embodiment and embodiments 1-4 is that the reinforcing agent solution is a potassium carbonate solution and the water-reducing agent dosage is 0.3%.

Claims

1. An alkali-activated porous geopolymer wall material using recycled fine aggregate loaded with a reinforcing agent, characterized in that... The alkali-activated porous geopolymer wall material is prepared from recycled fine aggregate, reinforcing agent, cementitious material, alkali activator, foaming agent, and water-reducing agent, wherein: The reinforcing agent accounts for 87-95% of the saturated water absorption rate of the recycled fine aggregate; The mass ratio of the cementitious material to the recycled fine aggregate is 1:2; The cementing material is water slag and fly ash, and the mass ratio of water slag to fly ash is 5:5~6:4; The alkaline activator is sodium hydroxide and water glass, with an alkaline activator modulus of 1.2 to 1.4 and an alkaline content of 5% to 8%. The foaming agent is added at a rate of 0.25-0.6% of the total mass of the cementitious material; The water-reducing agent is added at a rate of 0.1% to 0.3% of the total mass of slag and fly ash.

2. The alkali-activated porous geopolymer wall material using recycled fine aggregate loaded with a reinforcing agent according to claim 1, characterized in that... The reinforcing agent is a carbonate or bicarbonate, the water-reducing agent is a naphthalene-based water-reducing agent, and the foaming agent is hydrogen peroxide.

3. The alkali-activated porous geopolymer wall material using recycled fine aggregate loaded with a reinforcing agent according to claim 1, characterized in that... The mass ratio of water slag to fly ash is 6:

4.

4. The alkali-activated porous geopolymer wall material using recycled fine aggregate loaded with a reinforcing agent according to claim 1, characterized in that... The alkali activator has a modulus of 1.4 and an alkali content of 5%.

5. The alkali-activated porous geopolymer wall material using recycled fine aggregate loaded with a reinforcing agent according to claim 1, characterized in that... The water-reducing agent is added at a rate of 0.103% of the total mass of slag and fly ash.

6. The alkali-activated porous geopolymer wall material using recycled fine aggregate loaded with a reinforcing agent according to claim 1, characterized in that... The foaming agent is added at a rate of 0.25%, 0.40%, or 0.50% of the total mass of water slag and fly ash.

7. The alkali-activated porous geopolymer wall material using recycled fine aggregate loaded with a reinforcing agent according to claim 1, characterized in that... The particle size distribution of the recycled fine aggregate is as follows: 45-55% of the particles are 0.15-1.5 mm, 35-45% are 1.0-3.0 mm, and 5-15% are 3.0-4.75 mm.

8. A method for preparing an alkali-activated porous geopolymer wall material using recycled fine aggregate loaded with a reinforcing agent as described in any one of claims 1-7, characterized in that... The method includes the following steps: Step S1: Based on the saturated surface-dry water absorption rate of the recycled fine aggregate and the water-cement ratio of the recycled mortar, weigh the reinforcing agent solution, mix it evenly with the recycled fine aggregate, and let it stand for 5-14 hours to obtain the pretreated aggregate. Step S2: Mix the pretreated aggregate, water slag and fly ash, add water reducing agent, and stir slowly for 1-5 minutes; Step S3: Mix the foaming agent and alkali activator, pour them into the mixing pot of step S2, and mix the liquid and powder thoroughly. Then add water to adjust the water-cement ratio to 0.55~0.

6. Step S4: Pour the slurry obtained in step S3 into the mold, vibrate to remove air bubbles, cover with plastic wrap, and place in a drying oven for curing for 6-10 hours. Step S5: Take out the gas-generating mortar obtained in step S4 and saw off the loose part formed on the top of the mortar due to gas accumulation during the gas generation process. Step S6: Place the gas-generating mortar obtained in step S5 into a drying oven for continued curing. After 20-30 hours, remove it from the mold and place it in a room temperature environment for curing until 7 days.

9. The method for preparing alkali-activated porous geopolymer wall material using recycled fine aggregate loaded with reinforcing agent according to claim 8, characterized in that... The mass concentration of the reinforcing agent solution is 5-20%.

10. The method for preparing alkali-activated porous geopolymer wall material using recycled fine aggregate loaded with reinforcing agent according to claim 8, characterized in that... The vibration frequency is 30Hz, the time is 20~40s; the drying oven temperature is 40~50℃.

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