Autoclaved aerated concrete material, panel and building structure

Abstract

This invention discloses autoclaved aerated concrete (AAC) materials, slabs, and building structures, belonging to the field of building materials. The AAC material comprises the following components in parts by weight: 300-350 parts wet-discharge slag ash; 45-55 parts solid waste-based cementitious material; 20-25 parts first desulfurization gypsum; 2.0-2.5 parts AAC product waste; 15-35 parts inorganic hydrophobic agent; 10-20 parts organic hydrophobic agent; 1-3 parts ionic liquid mineralizer; 50-60 parts lime; 1-3 parts polycarboxylate superplasticizer; and 3.0-3.5 parts aluminum powder paste. This AAC material has low water absorption, which improves the waterproof durability of AAC slabs, and also exhibits excellent circular economy benefits and energy-saving and emission-reduction characteristics.

Description

Technical Field

[0001] This invention relates to the field of building materials, and particularly to autoclaved aerated concrete materials, panels, and building structures. Background Technology

[0002] Autoclaved aerated concrete (AAC) panels refer to porous concrete panels made primarily from silica sand, cement, lime, or fly ash, and cured under high pressure with steam.

[0003] In related technologies, AAC boards have strong water absorption properties, which limits their use in wet-dry cycles, long-term water exposure, humid or underground environments, often leading to waterproofing failure. Furthermore, due to the rapid water absorption rate of AAC boards, ordinary water-based waterproof coatings applied to their surface are easily "captured" by the AAC board's surface, thus affecting the coating's curing and setting.

[0004] It is evident that reducing the water absorption rate of AAC boards is essential. Summary of the Invention

[0005] In view of this, the present invention provides an autoclaved aerated concrete material, a slab, and a building structure, which can solve the technical problems existing in related technologies.

[0006] Specifically, the following technical solutions are included:

[0007] On one hand, an autoclaved aerated concrete (AAC) material is provided, the AAC material comprising the following components in parts by weight:

[0008]

[0009]

[0010] In some possible implementations, the wet-discharged slag ash exists in the form of slag slurry when used for plate preparation, the slag slurry having at least one of the following characteristics: moisture content of 35% to 45% and particle size of 15% to 35% residue on an 80 μm sieve.

[0011] In some possible implementations, the autoclaved aerated product waste exists in the form of an autoclaved aerated nanoparticle aqueous suspension when applied, and the solid content of the autoclaved aerated nanoparticle aqueous suspension is 5%-25%.

[0012] The autoclaved aerated concrete nanoparticle aqueous suspension comprises: autoclaved aerated concrete waste, composite activator and water;

[0013] The mass of the composite activator is 0.01%-0.05% of the mass of the autoclaved aerated concrete waste. The composite activator comprises triethanolamine, ethylene glycol, sodium silicate, sodium sulfite, glycerol, stearic acid, and sodium hexametaphosphate in a mass ratio of 5-10:5-10:2-5:1-3:1-3:1-3:1.

[0014] In some possible implementations, the inorganic hydrophobic agent comprises the following components: lamellar mica powder, barium sulfate, and silica aerogel dispersion in a mass ratio of 5–10:1–5:1.

[0015] In some possible implementations, the organic hydrophobic agent comprises: polyvinyl alcohol wax powder and pregelatinized starch in a mass ratio of 0.5 to 2:1.

[0016] In some possible implementations, the ionic liquid mineralizer comprises a bicarbonate, the chemical structural formula of which is shown below:

[0017]

[0018] Among them, Z + It is a 2-methylimidazolium chloride cation, a 4-methylimidazolium chloride cation, a 2-ethylimidazolium chloride cation, or a 4-ethylimidazolium chloride cation.

[0019] On the other hand, embodiments of the present invention also provide an autoclaved aerated concrete (AAC) panel, wherein the AAC panel is prepared using any of the autoclaved aerated concrete materials described above.

[0020] In some possible implementations, the autoclaved aerated concrete (AAC) panels are prepared by a constant-temperature autoclaving process.

[0021] After the constant temperature autoclaving process is completed, the autoclaved aerated concrete slab is subjected to carbonation treatment and / or surface hydrophobic treatment.

[0022] In another aspect, embodiments of the present invention also provide a building structure, the building structure comprising a horizontal slab and a vertical wall, both the horizontal slab and the vertical wall being prepared using the aforementioned autoclaved aerated concrete panels;

[0023] The surface of the horizontal slab has a first receiving groove and a second receiving groove. The first end of the vertical wall has a protrusion, which is accommodated inside the first receiving groove. The second receiving groove and the corresponding positions between the end face of the first end of the vertical wall and the surface of the horizontal slab are filled with waterproof mortar.

[0024] The joint between the vertical wall and the horizontal slab is sealed with waterproof sealant.

[0025] In some possible implementations, the surfaces of both the horizontal plate and the vertical wall have a waterproof primer layer and a waterproof coating layer arranged sequentially.

[0026] The beneficial effects of the technical solutions provided in the embodiments of the present invention include at least the following:

[0027] The autoclaved aerated concrete (AAC) material provided in this invention uses wet-discharged slag ash instead of traditional siliceous materials as the matrix material, solid waste-based cementitious materials instead of traditional cement materials, and first desulfurized gypsum as a regulating material. It further combines autoclaved aerated concrete product waste, inorganic hydrophobic agents, organic hydrophobic agents, ionic liquid mineralizers, lime, polycarboxylate superplasticizers, and aluminum powder paste. These components are combined in a specific ratio and work synergistically to enhance the hydrophobic properties of the AAC material and reduce its water absorption rate. This results in a lower water absorption rate for AAC panels prepared from this material, thereby improving their waterproof durability. Furthermore, many components in this AAC material can be derived from waste materials, giving it excellent circular economy benefits and energy-saving and emission-reduction characteristics. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 A schematic diagram of an exemplary building structure provided in an embodiment of the present invention;

[0030] Figure 2 This is a schematic diagram of an exemplary vertical wall provided in an embodiment of the present invention;

[0031] Figure 3 This is a schematic diagram of an exemplary horizontal plate provided in an embodiment of the present invention.

[0032] The reference numerals in the attached figures represent:

[0033] 1-Vertical wall; 10-Protrusion;

[0034] 2-Horizontal plate; 21-First receiving groove; 22-Second receiving groove;

[0035] 3-Waterproof mortar. Detailed Implementation

[0036] To make the technical solutions and advantages of the present invention clearer, the embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

[0037] In view of the fact that autoclaved aerated concrete (AAC) has a high water absorption rate in related technologies, this invention provides an AAC panel with a low water absorption rate and its raw materials.

[0038] On one hand, embodiments of the present invention provide an autoclaved aerated concrete material, which comprises the following components in parts by weight:

[0039]

[0040] The autoclaved aerated concrete (AAC) material provided in this invention uses wet-discharged slag ash instead of traditional siliceous materials as the matrix material, solid waste-based cementitious materials instead of traditional cement materials, and first desulfurized gypsum as a regulating material. It further combines autoclaved aerated concrete product waste, inorganic hydrophobic agents, organic hydrophobic agents, ionic liquid mineralizers, lime, polycarboxylate superplasticizers, and aluminum powder paste. These components are combined in a specific ratio and work synergistically to enhance the hydrophobic properties of the AAC material and reduce its water absorption rate. This results in a lower water absorption rate for AAC panels prepared from this material, thereby improving their waterproof durability. Furthermore, many components in this AAC material can be derived from waste materials, giving it excellent circular economy benefits and energy-saving and emission-reduction characteristics.

[0041] Regarding the formulation of autoclaved aerated concrete (AAC) materials, the following will further elaborate on the components and their functions.

[0042] For wet-discharge slag ash, its weight percentage in autoclaved aerated concrete materials is 300-350 parts, including but not limited to: 300 parts, 310 parts, 320 parts, 330 parts, 340 parts, 350 parts, etc.

[0043] When wet-discharged slag ash is used in the preparation of slabs, it exists as slag slurry. In some examples, the slag slurry has at least one of the following characteristics: moisture content of 35% to 45% and particle size of 15% to 35% residue on an 80 μm sieve, which facilitates uniform mixing with other components and makes it easy to form autoclaved aerated concrete slabs.

[0044] Wet-discharge slag ash is a common material in this field. In the embodiments of the present invention, wet-discharge slag ash is, for example, waste slag from the bottom of a coal-fired power plant.

[0045] For example, the moisture content of wet-discharge slag ash is 15% to 30%, and the particle size is 30 mm to 100 mm, such as 50 mm. The mass percentage of SiO2 contained in the wet-discharge slag ash is greater than or equal to 45%.

[0046] Typically, wet-discharge slag ash is difficult to manage due to its high moisture content and irregular shape, and is often dumped outdoors or landfilled. However, this invention innovatively recycles wet-discharge slag ash, using it as a substrate material for slabs, thereby achieving excellent circular economy benefits and energy conservation and emission reduction features.

[0047] Before use, wet-discharged slag ash can be processed by wet ball milling to prepare slag ash slurry with a moisture content of 35% to 45% and a particle size of 15% to 35% residue on an 80μm sieve.

[0048] For solid waste-based cementitious materials, their weight percentage in autoclaved aerated concrete materials is 45 to 55 parts, including but not limited to: 45 parts, 46 parts, 47 parts, 48 ​​parts, 49 parts, 50 parts, 51 parts, 52 parts, 53 parts, 54 parts, 55 parts, etc.

[0049] In some examples, the solid waste-based cementitious material comprises the following components in weight percentages: 15%–35% steel slag, 25%–60% blast furnace slag, 5%–25% secondary desulfurization gypsum, 5%–25% fly ash, and 0.1%–1% polyacrylamide modifier.

[0050] Steel slag, blast furnace slag, desulfurized gypsum, fly ash and polyacrylamide modifier are all common materials in this field. The solid waste-based cementitious materials can be prepared by ball milling and mixing the above components.

[0051] This invention utilizes a certain proportion of steel slag, blast furnace slag, desulfurized gypsum, fly ash, and polyacrylamide modifier in a synergistic effect to replace traditional high-energy-consuming cementitious materials such as cement with solid waste-based cementitious materials. This not only improves the overall performance of autoclaved aerated concrete (AAC) panels but also enables the recycling of waste, achieving the goal of energy conservation and emission reduction.

[0052] In some examples, the prepared solid waste-based cementitious materials have a specific surface area of ​​300 m². 2 / kg~500m 2 / kg, with a 28-day compressive strength of up to 35MPa~55MPa.

[0053] Steel slag in solid waste-based cementitious materials is a byproduct of the steelmaking process. Under normal circumstances, steel slag contains the following components by mass percentage: 2% to 8% metallic iron, 40% to 60% calcium oxide, 3% to 10% magnesium oxide, and the balance being other components.

[0054] Slag in solid waste-based cementitious materials is a byproduct of the blast furnace ironmaking process. During ironmaking, iron oxide is reduced to metallic iron at high temperatures. Impurities such as silica and alumina in iron ore react with lime to form a molten material mainly composed of silicates and aluminosilicates. After quenching, slag is formed. Slag is a loose, porous granular material. Under normal circumstances, the mass percentage of CaO, SiO2, and Al2O3 in slag is more than 90%.

[0055] The second desulfurization gypsum in solid waste-based cementitious materials is one of the solid wastes from coal-fired power plants, and its main component is CaSO4·2H2O. Fly ash is also one of the solid wastes from coal-fired power plants. Under normal circumstances, it contains ≥40% SiO2 by mass, 5%–55% particle size residue on a 45μm sieve, and ≤3% loss on ignition.

[0056] In some examples, the polyacrylamide modifier can have a particle size of 80 mesh and a molecular weight of 18 million. It is a white powder linear polymer with a molecular weight of 18 million, which can improve the mixing and ball milling efficiency of solid waste-based cementitious materials and enhance their mechanical properties.

[0057] For the first desulfurization gypsum, its weight proportion in autoclaved aerated concrete material is 20 to 25 parts, including but not limited to: 20 parts, 21 parts, 22 parts, 23 parts, 24 parts, 25 parts, etc.

[0058] The first desulfurization gypsum is one of the solid wastes from coal-fired power plants, and its main component is CaSO4·2H2O. Before use, the first desulfurization gypsum can be ball-milled alone or ball-milled together with wet-discharged slag ash and mixed into the slag slurry.

[0059] For autoclaved aerated concrete (AAC) product waste, its weight proportion in AAC material is 2.0 to 2.5 parts, including but not limited to: 2.0 parts, 2.1 parts, 2.2 parts, 2.3 parts, 2.4 parts, 2.5 parts, etc.

[0060] In this embodiment of the invention, the waste material of autoclaved aerated products exists in the form of an aqueous suspension of autoclaved aerated nanoparticles, and the solid content of the aqueous suspension of autoclaved aerated nanoparticles is 5%-25%.

[0061] When autoclaved aerated concrete (AAC) products are used, the waste exists in the form of an AAC nanoparticle aqueous suspension. The solid particles in the suspension are relatively fine, which can reduce the nucleation barrier in the subsequent AAC concrete products.

[0062] The autoclaved aerated concrete nanoparticle aqueous suspension comprises: autoclaved aerated concrete waste, composite activator and water. The autoclaved aerated concrete waste and composite activator together constitute the autoclaved aerated concrete product waste. The solid content of the autoclaved aerated concrete nanoparticle aqueous suspension, that is, the total mass percentage of autoclaved aerated concrete waste and composite activator, is 5%-25%.

[0063] The mass of the composite activator is 0.01%-0.05% of the mass of autoclaved aerated concrete waste, including but not limited to: 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, etc.

[0064] The composite activator includes triethanolamine, ethylene glycol, sodium silicate, sodium sulfite, glycerol, stearic acid, and sodium hexametaphosphate in a mass ratio of 5-10:5-10:2-5:1-3:1-3:1-3:1.

[0065] The aforementioned composite activator can help refine autoclaved aerated concrete waste into an autoclaved aerated nanoparticle aqueous suspension, thus acting as a grinding aid.

[0066] In some examples, the autoclaved aerated concrete (AAC) nanoparticle aqueous suspension is prepared by the following method: Waste solids from traditional AAC products are used as AAC waste material. This AAC waste material is crushed, for example, using a jaw crusher. Further, the crushed AAC waste particles are ground together with a composite activator and water, for example, using a wet ball mill, to prepare the AAC nanoparticle aqueous suspension. The particle size of the solid powder contained in the AAC nanoparticle aqueous suspension is in the nanometer range, for example, 1 nm to 100 nm.

[0067] The autoclaved aerated concrete (AAC) product waste provided in this embodiment of the invention has a nano-induced crystallization nucleation effect, which can significantly reduce the nucleation barrier of tobermorite. This helps to form tobermorite crystals during the autoclaving process of AAC materials, improves crystallinity, and achieves the effect of strengthening and densifying the board, reducing the water absorption rate of the board. It also facilitates the use of local materials and expands the high-value recycling of waste AAC materials.

[0068] The embodiments of the present invention utilize functional additives such as inorganic hydrophobic agents, organic composite hydrophobic agents, and ionic liquid mineralizers to enhance the hydrophobic properties of materials and reduce water absorption.

[0069] For inorganic hydrophobic agents, the weight parts in autoclaved aerated concrete materials are 15 to 35 parts, including but not limited to: 15 parts, 16 parts, 17 parts, 18 parts, 19 parts, 20 parts, 21 parts, 22 parts, 23 parts, 24 parts, 25 parts, 26 parts, 27 parts, 28 parts, 29 parts, 30 parts, 31 parts, 32 parts, 33 parts, 34 parts, 35 parts, etc.

[0070] In some examples, the inorganic hydrophobic agent is a nanoparticle comprising the following components: lamellar mica powder, barium sulfate, and silica aerogel dispersion in a mass ratio of 5–10:1–5:1.

[0071] Lamellar mica powder is a layered silicate, typically containing 40% to 50% SiO2 by mass. It is made from mica fragments through processes such as washing, impurity removal, soaking, crushing, low-temperature drying, and sieving. Microscopically, it exhibits a layered, scaly structure. Lamellar mica powder can improve the hydrophobicity of autoclaved aerated concrete materials and slabs.

[0072] Barium sulfate is an amorphous powder that is poorly soluble in water and has a water-repellent effect, which can improve the hydrophobicity of autoclaved aerated concrete materials and slabs.

[0073] Silica aerogel dispersions can be made using commercially available nano-silica aerogel aqueous dispersions. These are white pastes, and typically have a density of 0.40 g / cm³. 3 ~0.60g / cm 3 With a solid content of 10% to 30%, it can improve the hydrophobicity and thermal insulation of autoclaved aerated concrete materials and panels.

[0074] For organic hydrophobic agents, the weight parts in autoclaved aerated concrete materials are 10 to 20 parts, including but not limited to: 10 parts, 11 parts, 12 parts, 13 parts, 14 parts, 15 parts, 16 parts, 17 parts, 18 parts, 19 parts, 20 parts, etc.

[0075] In some examples, the organic hydrophobic agent includes polyvinyl alcohol wax powder and pregelatinized starch in a mass ratio of 0.5 to 2:1.

[0076] Polyvinyl alcohol wax powder is a loose white powder with an average particle size of 3μm to 6μm and a hot-melt temperature of 150℃ to 200℃. The above-mentioned mass fraction of polyvinyl alcohol wax powder can be melted into a film during the autoclaved aerated concrete (AAC) slab curing stage, thereby sealing the water-absorbing pores of the AAC slab and further improving the hydrophobicity of the AAC slab.

[0077] Pregelatinized starch appears as a white powder with a particle size of, for example, 50-100 mesh, or even 90 mesh. It swells in cold water to form a white, transparent liquid. When the mass concentration of pregelatinized starch is 2%, the resulting aqueous solution of pregelatinized starch can reach a viscosity of 300 mPa·s.

[0078] Pregelatinized starch can gelatinize during the autoclaving stage of autoclaved aerated concrete (AAC), enhancing the internal adhesion and cohesiveness of AAC panels, sealing water-absorbing pores, and thus improving its hydrophobicity.

[0079] For ionic liquid mineralizers, the weight parts in autoclaved aerated concrete materials are 1 to 3 parts, including but not limited to: 1 part, 1.1 parts, 1.2 parts, 1.3 parts, 1.4 parts, 1.5 parts, 1.6 parts, 1.7 parts, 1.8 parts, 1.9 parts, 2.0 parts, 2.1 parts, 2.2 parts, 2.3 parts, 2.4 parts, 2.5 parts, 2.6 parts, 2.7 parts, 2.8 parts, 2.9 parts, 3.0 parts, etc.

[0080] In some examples, the ionic liquid mineralizer includes bicarbonate, the chemical structural formula of which is shown below:

[0081]

[0082] Among them, Z + It is a 2-methylimidazolium chloride cation, a 4-methylimidazolium chloride cation, a 2-ethylimidazolium chloride cation, or a 4-ethylimidazolium chloride cation.

[0083] Ionic liquid mineralizers can decompose and release carbon dioxide during the steam curing stage of autoclaved aerated concrete (AAC), enabling the excess calcium hydroxide in the AAC to undergo carbonization and crystallization during the steam curing stage. This densifies the internal structure, seals the water-absorbing pores, reduces the water absorption rate of AAC products, and improves the strength of AAC products.

[0084] The ionic liquid mineralizer is a bicarbonate ionic liquid, which can be prepared by the following method: A cation source and sodium bicarbonate are mixed in an organic solvent at a molar ratio of 1:(1-2), stirred for 24-48 hours, and then allowed to stand for solid-liquid separation to obtain a supernatant. The organic solvent is removed from the supernatant by vacuum distillation or vacuum drying to obtain the bicarbonate ionic liquid.

[0085] Among them, the cation source is a Z-type cation source. + The chloride salt; the organic solvent is an alcohol or ketone solvent, for example, an alcohol solvent can be ethanol, and a ketone solvent can be acetone, etc.

[0086] The weight of lime in autoclaved aerated concrete is 50 to 60 parts, including but not limited to: 50 parts, 51 parts, 52 parts, 53 parts, 54 parts, 55 parts, 56 parts, 57 parts, 58 parts, 59 parts, 60 parts, etc.

[0087] In some examples, the lime is crushed and ground to form a powder with a particle diameter of 20%–25% residue on an 80µm sieve. In some examples, the lime has an effective calcium content of ≥75% by mass, a slaking time of 5–15 min, and a slaking temperature of 70℃–100℃.

[0088] For polycarboxylate superplasticizers, the weight parts in autoclaved aerated concrete materials are 1 to 3 parts, including but not limited to: 1 part, 1.1 parts, 1.2 parts, 1.3 parts, 1.4 parts, 1.5 parts, 1.6 parts, 1.7 parts, 1.8 parts, 1.9 parts, 2.0 parts, 2.1 parts, 2.2 parts, 2.3 parts, 2.4 parts, 2.5 parts, 2.6 parts, 2.7 parts, 2.8 parts, 2.9 parts, 3.0 parts, etc.

[0089] Polycarboxylate superplasticizers can be commercially available products. They are based on acrylic acid or methacrylic acid as the main chain, grafted with polyethers of different side chain lengths, and meet the requirements of the standard "Polycarboxylate Superplasticizers" JG / T 223~2007.

[0090] In this embodiment of the invention, the water reduction rate of the polycarboxylate superplasticizer can be ≥25% and the bleeding rate ≤60%, thereby achieving the effects of strengthening the autoclaved aerated concrete raw materials, reducing concrete shrinkage, and endowing the autoclaved aerated concrete raw materials with excellent workability, superior strength and durability.

[0091] For aluminum powder paste, its weight parts in autoclaved aerated concrete materials are 3.0 to 3.5 parts, including but not limited to: 3.0 parts, 3.1 parts, 3.2 parts, 3.3 parts, 3.4 parts, 3.5 parts, etc.

[0092] In this embodiment of the invention, aluminum powder paste is mainly used as a gas-generating material. For example, the solid content of aluminum powder paste can be ≥65%, and the mass percentage of aluminum contained in the solid part is greater than or equal to 90%.

[0093] On the other hand, embodiments of the present invention provide an autoclaved aerated concrete (AAC) panel, which is prepared from any of the aforementioned autoclaved aerated concrete materials.

[0094] The autoclaved aerated concrete (AAC) panels provided in this embodiment of the invention possess all the advantages of the aforementioned AAC materials.

[0095] In another aspect, embodiments of the present invention provide a method for preparing autoclaved aerated concrete (AAC) panels, wherein the AAC panels are as described above, and the AAC materials used are as described above.

[0096] The preparation method of this autoclaved aerated concrete panel includes:

[0097] Add the slag slurry corresponding to the wet-discharge slag ash, the first desulfurization gypsum, the autoclaved aerated concrete product waste, the inorganic hydrophobic agent, the organic hydrophobic agent, the ionic liquid mineralizer, and the polycarboxylate superplasticizer to the casting mixer, and stir evenly.

[0098] Continue adding solid waste-based cementitious materials, lime, and aluminum powder paste to the casting mixer, and mix evenly to form a casting slurry.

[0099] The autoclaved aerated concrete (AAC) panel preparation process involves preparing AAC panels using cast slurry, which includes the following steps.

[0100] The slurry is poured into the mold, and a wire mesh cage is inserted into the mold so that the wire mesh cage is immersed in the slurry.

[0101] In a constant temperature environment of 40℃~60℃, the slurry is allowed to stand for 1.5h~3.5h to generate gas and initially set, thus obtaining the green body.

[0102] The blank is cut and shaped, and then subjected to constant temperature autoclaving to obtain autoclaved aerated concrete slabs.

[0103] For example, an embodiment of the present invention provides a preparation method for autoclaved aerated concrete (AAC) panels, as shown below:

[0104] Wet-discharged slag ash is wet-milled into a slurry to obtain a slag ash slurry with a particle size of 15% to 35% residue on an 80 μm sieve and a moisture content of 35% to 45%.

[0105] According to the weight proportions of each component in the autoclaved aerated concrete (AAC) raw materials, add the slag slurry corresponding to the wet-discharge slag ash, the first desulfurization gypsum, AAC product waste, inorganic hydrophobic agent, organic hydrophobic agent, ionic liquid mineralizer, and polycarboxylate superplasticizer to the casting mixer, and stir for 90s to 120s until uniformly mixed. The components can be added sequentially.

[0106] Continue adding solid waste-based cementitious materials and lime to the casting mixer, and stir for 40 to 60 seconds until uniformly mixed. Continue adding aluminum powder paste to the casting mixer and stir for 30 to 50 seconds until uniformly mixed to form a casting slurry.

[0107] The slurry is poured into the mold, and a wire mesh cage is inserted into the mold so that the wire mesh cage is immersed in the slurry.

[0108] In a constant temperature environment of 40℃~60℃, the slurry is allowed to stand for 1.5h~3.5h to generate gas and initially set, thus obtaining the green body.

[0109] The blank is cut and shaped (e.g., cut into strips), and then subjected to constant temperature autoclaving to obtain autoclaved aerated concrete slabs.

[0110] In some examples, embodiments of the present invention provide a constant temperature autoclaving process, which includes the following steps:

[0111] Place the preform in an autoclave, close the autoclave door, open the bottom drain valve, and introduce curing steam into the autoclave. Control the steam introduction rate and pressure rise rate. After 50-70 minutes, the pressure inside the autoclave rises from 0 to the first pressure, for example, 0.1 MPa. At this point, close the drain valve 1 / 3. After another 40-60 minutes, the pressure inside autoclave I rises to the second pressure, for example, 0.3 MPa. At this point, close the drain valve 2 / 3. After another 20-40 minutes, the pressure inside the autoclave rises to the third pressure, for example, 0.5 MPa. At this point, fully close the drain valve. After 10-15 minutes, open the drain valve 1 / 10. After another 30-50 minutes, the pressure inside the autoclave rises to 1.2 MPa-1.5 MPa, and the temperature reaches 195℃-205℃. Maintain this temperature and pressure for 6-10 hours. Remove the residual gas from the autoclave, controlling the steam conduction rate and pressure reduction rate. After 2.5 to 3.5 hours, reduce the pressure to the fourth pressure, for example, 0.3 MPa. Continue removing the residual gas from the autoclave until the pressure inside the autoclave is reduced to the fifth pressure, for example, 0.1 MPa, thus completing the isothermal autoclaving.

[0112] When performing constant temperature and pressure curing, multiple autoclaves can be used simultaneously to continuously circulate among them, thereby increasing the production capacity of the boards treated under constant temperature and pressure.

[0113] For example, autoclave I, autoclave II, and autoclave III can be used for constant temperature and pressure operation. After the constant temperature autoclaving in autoclave I is completed, the residual steam in autoclave I can be introduced into autoclave II for the steam curing of the blanks in autoclave II. The steam conduction rate and pressure reduction rate of autoclave I are controlled. After the pressure is reduced to the fourth pressure in 2.5h to 3.5h, the residual steam in autoclave I is introduced into autoclave III for the steam curing of the blanks in autoclave III until the pressure in autoclave I is reduced to the fifth pressure, thus completing the constant temperature autoclaving.

[0114] In some examples, after the isothermal autoclaving process is completed, the autoclaved aerated concrete slabs are subjected to at least one of carbonation treatment and surface hydrophobic treatment.

[0115] Carbonation treatment can increase the apparent density of autoclaved aerated concrete (AAC) panels, further improving their strength and hydrophobicity, thereby enhancing their waterproof performance. Similarly, surface hydrophobic treatment can improve the surface hydrophobicity of AAC panels, also achieving the goal of further enhancing their waterproof performance.

[0116] For example, after the green body is cured by constant temperature autoclaving, the resulting autoclaved aerated concrete (AAC) panels are subjected to carbonation curing, thereby increasing the apparent density of the AAC panels and further improving their strength and hydrophobicity.

[0117] In some examples, carbonization curing includes: placing the autoclaved aerated concrete slabs obtained after constant temperature autoclaving into an autoclave, and introducing a carbon-containing gas stream into the autoclave, for example, the carbon-containing gas stream is the flue gas from a power plant desulfurization duct (the main components of the flue gas from a power plant desulfurization duct are conventional flue gas substances such as carbon dioxide), and the carbon-containing gas stream is introduced for 5 to 10 minutes to carry out carbonization curing.

[0118] In some examples, the carbonization curing time is 2 to 5 hours to achieve full carbonization.

[0119] After carbonization curing is completed, the exhaust valve at the top of the autoclave is slowly opened to release the residual steam and desulfurization flue gas into the natural environment outside the plant. The product inside the autoclave is then discharged to obtain the autoclaved aerated concrete panel product.

[0120] The above arrangement promotes the conversion of residual calcium hydroxide on the surface of autoclaved aerated concrete (AAC) panels into calcium carbonate crystals, thereby increasing surface density and sealing and blocking water-absorbing pores.

[0121] In some examples, the surface of autoclaved aerated concrete (AAC) panels is treated with a hydrophobic coating to further improve the hydrophobicity of AAC panels, reduce their water absorption characteristics, and enhance the overall performance of AAC panels.

[0122] For example, the hydrophobic treatment is a n-octyltriethoxysilane film-forming treatment, which includes: applying an n-octyltriethoxysilane solution to the surface of an autoclaved aerated concrete (AAC) slab, and drying it to obtain an AAC slab with a hydrophobic coating on its surface. The n-octyltriethoxysilane solution may be applied to the surface of the AAC slab once, or twice, three times, or more.

[0123] The n-octyltriethoxysilane solution is prepared by the following method: providing an aqueous acetic acid solution with a pH of 3.5 to 4.5, adding n-octyltriethoxysilane to the aqueous acetic acid solution to make the mass concentration of n-octyltriethoxysilane 1% to 2%, stirring for at least 30 minutes until the n-octyltriethoxysilane is completely dissolved and transparent, thus preparing the n-octyltriethoxysilane solution.

[0124] The chemical structural formula of n-octyltriethoxysilane is shown below:

[0125]

[0126] The n-octyltriethoxysilane involved in the embodiments of this invention can be selected from commercially available products, for example, Dow Corning Z-6341 and Momentive. At least one of A-137 and Evonik OCTEO from Germany is suitable.

[0127] In some examples, when performing the n-octyltriethoxysilane film-forming treatment, the autoclaved aerated concrete (AAC) slab can be clamped using a clamping machine, and the n-octyltriethoxysilane solution can be applied to multiple surfaces of the AAC slab using tools such as spray guns, rollers, and brushes, for example, large surfaces in both directions. The application is repeated until the surface of the slab remains moist for 5-15 minutes, after which it is allowed to dry naturally.

[0128] In summary, the autoclaved aerated concrete (AAC) panels prepared using the method provided in this embodiment of the invention have excellent hydrophobic properties and low water absorption, making them suitable for use as exterior wall panels, interior wall panels, floor panels, or roof panels in prefabricated buildings. With appropriate structural waterproofing techniques, they can be applied to various wet-dry cycles, long-term damp, watery environments, or underground environments.

[0129] Furthermore, embodiments of the present invention provide a building structure based on autoclaved aerated concrete panels, as shown in the attached figure. Figure 1 - Appendix Figure 3 As shown, the building structure includes a horizontal slab 2 and a vertical wall 1, both of which are made of autoclaved aerated concrete panels provided in this embodiment of the invention.

[0130] As attached Figure 3 As shown, the surface of the horizontal plate 2 has a first receiving groove 21 and a second receiving groove 22, as attached. Figure 2As shown, the first end of the vertical wall 1 has a protrusion 10. The protrusion 10 is accommodated inside the first receiving groove 21. The second receiving groove 22 and the corresponding positions between the end face of the first end of the vertical wall 1 and the surface of the horizontal plate 2 are filled with waterproof mortar 3. The joint between the vertical wall 1 and the horizontal plate 2 is filled with waterproof sealant.

[0131] The waterproof sealant involved in the embodiments of the present invention is at least one of silane-modified polyurethane sealant or silane-modified polyether sealant.

[0132] This building structure is based on autoclaved aerated concrete (AAC) panels with low water absorption provided in this embodiment of the invention, and waterproofing measures are applied to the connection between the horizontal panel 2 and the vertical wall 1, resulting in a building structure with good waterproofing properties. Therefore, this low-water-absorption AAC panel can be used for waterproofing building structures that are subjected to long-term wet-dry cycles, dampness, or water content.

[0133] Understandably, the first end of the vertical wall 1, i.e. the lower end, has an inverted "L" shape, and the horizontal slab 2 can be a floor slab.

[0134] For example, the thickness of the main section of the vertical wall 1 can be 15cm, and the length of the protrusion 10 at the first end of the vertical wall 1 can be 10cm (i.e., the protrusion height), and the width can be 5cm. Of course, the above dimensions can be adjusted according to the actual application scenario; this example is merely an illustration.

[0135] For example, the main body of the horizontal plate 2 can be 15cm thick. The horizontal plate 2 has a first receiving groove 21 and a second receiving groove 22 at the installation position corresponding to the vertical wall 1; both are blind grooves. The first receiving groove 21 is configured to fit with the protrusion 10 with a clearance, and the depth of the first receiving groove 21 is less than the length of the protrusion 10, so that there is a gap between the first end of the vertical wall 1 and the surface of the horizontal plate 2. The first receiving groove 21 and the second receiving groove 22 are arranged alternately, and the projections of the first receiving groove 21 to the second receiving groove 22 on the horizontal plate 2 are located within the projection of the first end of the vertical wall 1 on the horizontal plate 2, ensuring that after the vertical wall 1 is installed on the horizontal plate 2, it can completely cover the first receiving groove 21 and the second receiving groove 22.

[0136] For example, the first receiving groove 21 has a width of 6cm and a depth of 3cm. The dimensions of the second receiving groove 22 are adjusted according to the amount of waterproof mortar 3 used; for example, the second receiving groove 22 has a width of 4cm and a depth of 3cm. The interval between the first receiving groove 21 and the second receiving groove 22 is 5cm.

[0137] In some examples, the surfaces of the horizontal slab 2 and the vertical wall 1 are sequentially covered with a waterproof primer layer and a waterproof coating layer, thereby further enhancing the waterproof effect of the building structure.

[0138] Waterproof primer is a low-viscosity, hydrophilic polymer-modified emulsion or hydrophobic polymer curing primer with penetrating ability. It includes, but is not limited to, waterborne polyurethane emulsion, waterborne acrylic emulsion, waterborne styrene-acrylic emulsion, waterborne polyethylene-polyvinyl acetate emulsion, waterborne epoxy resin emulsion, solvent-based two-component polyurethane primer, penetrating epoxy curing primer, etc.

[0139] Waterproof coatings include, but are not limited to: polymer cement waterproof coatings, polyurethane waterproof coatings, polyurea waterproof coatings, etc. The elongation at break of the waterproof coating formed by the waterproof coating is 50% to 1500%, and the tensile strength is 3 MPa to 30 MPa.

[0140] The building structure based on autoclaved aerated concrete panels involved in the embodiments of the present invention can be constructed by the following methods:

[0141] (1) Horizontal slab installation: Horizontal slabs of the desired dimensions are prepared using autoclaved aerated concrete (AAC) panels. These slabs are then horizontally mounted on steel beams, with the ends of the slabs overlapping the steel beams by 9–12 cm. The slabs are connected to the steel beams using hook bolts, with one end of the hook bolt welded to the beam. Furthermore, adjacent horizontal slabs are connected using specialized adhesive mortar or polyurethane foam.

[0142] (2) Grooving of horizontal plate: Grooving is performed on the horizontal plate below the intended installation position of the vertical wall using a grooving device to prepare the first receiving groove and the second receiving groove.

[0143] (3) Vertical wall installation: The vertical wall is erected on the surface of the horizontal plate, so that the protrusion of the vertical wall is inserted into the first receiving groove of the horizontal plate, and the second receiving groove is located below the lower end face of the vertical wall. The upper end and side of the vertical wall are connected to the steel structure beam and steel structure column respectively through auxiliary connectors.

[0144] (4) Waterproof mortar and sealant filling: Waterproof mortar is filled and compacted in 2-3 layers into the second receiving groove and the gaps between the vertical wall and the horizontal slab. After the waterproof mortar has cured, waterproof sealant is used to fill the gaps at the inside corners of the cured waterproof mortar. For example, the inside corners are rounded with a radius of 5mm-50mm. Then, waterproof sealant is applied along the joint between the vertical wall and the horizontal slab, extending 1cm-5cm on each side of the joint with a thickness of 1mm-2mm.

[0145] After the waterproof sealant has been applied and cured, apply a waterproof primer to the entire surface of the vertical walls and horizontal slabs, with a coating amount of 0.1 kg / m². 2 ~0.3kg / m 2 .

[0146] (5) Application of waterproof coating: After the waterproof primer has dried, apply the waterproof coating in three coats to construct an overall waterproof layer on the floor and walls. After the first coat of waterproof coating is surface dry (until it is no longer sticky to the touch), apply the second coat of waterproof coating, brushing it perpendicular to the previous coat. After it dries, apply the third coat of waterproof coating. The final thickness of the waterproof coating on vertical walls should be 1.2mm to 2mm, and on horizontal surfaces, 1.5mm to 3mm.

[0147] In summary, the building structure prepared by the above method in the embodiments of the present invention has at least the following advantages:

[0148] (1) Using autoclaved aerated concrete (AAC) panels with low water absorption rate as building walls and floors fundamentally improves the drawback of high water absorption rate of ordinary AAC panels, making AAC panels applicable to wet and dry cycles, long-term immersion in water or water environments, without causing the wall to absorb water and become moldy due to high water absorption rate.

[0149] (2) By further waterproofing the connection structure between the horizontal slab and the vertical wall in the building structure, the water is blocked by the physical structure of the slab itself, while achieving a natural separation between the long-term damp area and the dry area. On the basis of the natural separation, a waterproof sill is constructed by waterproof mortar to completely block the water migration channel between the floor slabs of the damp and dry areas.

[0150] (3) By further constructing a waterproof coating on the surface of the horizontal slab and the vertical wall, efficient and long-lasting waterproofing can be achieved.

[0151] Some exemplary embodiments of the present invention will be described in more detail below. While preferred embodiments of the invention are described below, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Where specific techniques or conditions are not specified in the embodiments, they are performed in accordance with techniques or conditions described in the literature in the art or according to product instructions. Reagents or instruments whose manufacturers are not specified are all conventional products that can be obtained commercially.

[0152] In the following embodiments, the proportions of each component in the raw materials are all by weight, and the raw materials existing in solid form are all in micro-nano-scale powder form. The specific components of the raw materials are shown below.

[0153] Solid waste-based cementitious material, comprising the following components by weight percentage: 20% steel slag, 49% blast furnace slag, 15% secondary desulfurization gypsum, 15% fly ash, and 1% polyacrylamide modifier.

[0154] The first and second desulfurization gypsum are the same, both originating from solid waste from coal-fired power plants.

[0155] The waste from autoclaved aerated concrete (AAC) products exists as an aqueous suspension of AAC nanoparticles. The solid particles contained therein, i.e., the waste from AAC products, are nanoscale in size, with a particle size distribution ranging from 1 nm to 100 nm. The waste from AAC products includes AAC concrete waste and a composite activator. The composite activator includes triethanolamine, ethylene glycol, sodium silicate, sodium sulfite, glycerol, stearic acid, and sodium hexametaphosphate in a mass ratio of 6:8:3:2:2:2:1.

[0156] The autoclaved aerated concrete (AAC) nanoparticle aqueous suspension was prepared by the following method: Waste from traditional AAC products was used as AAC waste material, which was then crushed using a jaw crusher. The crushed AAC waste particles, a composite activator, and water were then ground using a wet ball mill to prepare the AAC nanoparticle aqueous suspension.

[0157] The inorganic hydrophobic agent comprises the following components: lamellar mica powder, barium sulfate, and silica aerogel dispersion in a mass ratio of 8:3:1.

[0158] The organic hydrophobic agent includes polyvinyl alcohol wax powder and pregelatinized starch in a mass ratio of 1.5:1.

[0159] The ionic liquid mineralizer is a bicarbonate, in which Z... + It is a 2-methylimidazolium chloride cation.

[0160] Example 1

[0161] This embodiment 1 provides an autoclaved aerated concrete (AAC) material and slab. The AAC material comprises the following components in parts by weight: 300 parts wet-discharge slag ash; 45 parts solid waste-based cementitious material; 25 parts first desulfurization gypsum; 2.5 parts autoclaved aerated concrete product waste; 35 parts inorganic hydrophobic agent; 20 parts organic hydrophobic agent; 3 parts ionic liquid mineralizer; 60 parts lime; 1 part polycarboxylate superplasticizer; and 3.5 parts aluminum powder paste.

[0162] Based on the above-mentioned autoclaved aerated concrete material, Example 1 also prepared autoclaved aerated concrete panels by the following method, the specific preparation steps of which are shown below:

[0163] 300 parts of wet-discharged slag ash and 25 parts of first desulfurization gypsum were wet-milled together to prepare a solid waste slurry with 15% residue on an 80µm sieve and a moisture content of 35%.

[0164] The waste from autoclaved aerated concrete (AAC) products exists as an aqueous suspension of AAC nanoparticles with a solid content of 25%, wherein the mass of the composite activator is 0.01% of the mass of the AAC concrete waste. Solid waste slurry is added to a casting mixer, followed by the sequential addition of 10 parts of the AAC nanoparticle aqueous suspension, 35 parts of an inorganic hydrophobic agent, 20 parts of an organic hydrophobic agent, 3 parts of an ionic liquid mineralizer, and 1 part of a polycarboxylate superplasticizer, and stirred for 100 seconds. Next, 45 parts of solid waste-based cementitious material and 60 parts of lime are added to the casting mixer, and stirred for 60 seconds. Finally, 3.5 parts of aluminum powder paste are added to the casting mixer and stirred for 50 seconds to form a casting slurry, which is then poured into a mold.

[0165] The slurry was allowed to stand at a constant temperature of 40℃ for 3.5 hours to allow for initial setting and gas generation, resulting in a green body. The green body was then subjected to constant temperature and pressure curing in an autoclave. During the heating phase, the steam conduction rate and pressure increase rate within the autoclave were controlled. The pressure inside the autoclave increased from 0 to 0.1 MPa after 50 minutes, then to 0.3 MPa after 40 minutes, then to 0.5 MPa after 20 minutes, and finally to 1.2 MPa after 30 minutes, maintaining a constant temperature and pressure of 195℃ for 10 hours. After the constant temperature and pressure period ended, the steam conduction rate and pressure reduction rate were controlled, and the pressure decreased to 0.3 MPa after 2.5 hours.

[0166] After the steam introduction is completed and the pressure inside the autoclave drops to 0.1 MPa, the steam introduction valve is closed, and the power plant desulfurization flue gas is introduced into the autoclave for 5 minutes to perform carbonation curing treatment on the autoclaved aerated concrete slabs for 3 hours.

[0167] An aqueous solution of acetic acid with a pH of 3.5 was prepared by reacting acetic acid and water. Octyltriethoxysilane was then added to the acetic acid solution to achieve a mass concentration of 1%, and the mixture was stirred for 30 minutes until the octyltriethoxysilane was completely dissolved and the solution became transparent. The octyltriethoxysilane solution was then sprayed twice onto both the front and back surfaces of an autoclaved aerated concrete (AAC) slab. After natural drying for 24 hours, the low-water-absorption AAC slab of Example 1 was obtained.

[0168] Example 2

[0169] This embodiment 2 provides an autoclaved aerated concrete (AAC) material and slab. The AAC material comprises the following components in parts by weight: 350 parts wet-discharge slag ash; 55 parts solid waste-based cementitious material; 20 parts first desulfurization gypsum; 2 parts autoclaved aerated concrete product waste; 15 parts inorganic hydrophobic agent; 10 parts organic hydrophobic agent; 1 part ionic liquid mineralizer; 50 parts lime; 1 part polycarboxylate superplasticizer; and 3 parts aluminum powder paste.

[0170] Based on the above-mentioned autoclaved aerated concrete material, Example 2 also prepared autoclaved aerated concrete panels by the following method, the specific preparation steps of which are shown below:

[0171] 350 parts of wet-discharged slag ash and 20 parts of first desulfurization gypsum were wet-milled into a slurry to prepare a solid waste slurry with 35% residue on an 80µm sieve and a moisture content of 45%.

[0172] The waste from autoclaved aerated concrete (AAC) products exists as an aqueous suspension of AAC nanoparticles with a solid content of 5%, wherein the mass of the composite activator is 0.01% of the mass of the AAC concrete waste. Solid waste slurry is added to a casting mixer, followed by the sequential addition of 40 parts of the AAC nanoparticle aqueous suspension, 15 parts of an inorganic hydrophobic agent, 10 parts of an organic hydrophobic agent, 1 part of an ionic liquid mineralizer, and 1 part of a polycarboxylate superplasticizer, and stirred for 120 seconds. Then, 55 parts of solid waste-based cementitious material and 50 parts of lime are added to the casting mixer, and stirred for 45 seconds. Finally, 3.0 parts of aluminum powder paste are added to the casting mixer and stirred for 48 seconds to form a casting slurry, which is then poured into a mold.

[0173] The slurry was allowed to stand at a constant temperature of 60℃ for 1.5 hours to allow for initial setting and gas generation, resulting in a green body. The semi-finished green body was then subjected to constant temperature autoclaving in an autoclave. During the heating phase, the steam conduction rate and pressure increase rate within the autoclave were controlled. After 70 minutes, the pressure inside the autoclave increased from 0 to 0.1 MPa; after another 60 minutes, it increased to 0.3 MPa; after another 40 minutes, it increased to 0.5 MPa; and after another 50 minutes, the pressure reached 1.3 MPa and the temperature reached 205℃. This constant temperature and pressure was maintained for 10 hours. After the constant temperature and pressure period, the steam conduction rate and pressure reduction rate were controlled, and the pressure decreased to 0.3 MPa after 3.5 hours.

[0174] After the steam introduction is completed and the pressure inside the autoclave drops to 0.1 MPa, the steam introduction valve is closed, and the power plant desulfurization flue gas is introduced into the autoclave for 10 minutes to perform carbonization curing treatment on the autoclaved aerated concrete slabs for 2 hours.

[0175] An aqueous solution of acetic acid with a pH of 4.5 was prepared by reacting acetic acid and water. Octyltriethoxysilane was then added to the acetic acid solution to achieve a mass concentration of 2%, and the mixture was stirred for 35 minutes until the octyltriethoxysilane was completely dissolved and the solution became transparent. The octyltriethoxysilane solution was then sprayed onto both the front and back surfaces of an autoclaved aerated concrete (AAC) slab in three separate applications. After air drying for 24 hours, the low-water-absorption AAC slab of Example 2 was obtained.

[0176] Example 3

[0177] This embodiment 3 provides an autoclaved aerated concrete (AAC) material and slab. The AAC material comprises the following components in parts by weight: 325 parts wet-discharge slag ash; 50 parts solid waste-based cementitious material; 23 parts first desulfurization gypsum; 2.25 parts autoclaved aerated concrete product waste; 25 parts inorganic hydrophobic agent; 15 parts organic hydrophobic agent; 2 parts ionic liquid mineralizer; 55 parts lime; 2 parts polycarboxylate superplasticizer; and 3.3 parts aluminum powder paste.

[0178] Based on the above-mentioned autoclaved aerated concrete material, Example 3 also prepared autoclaved aerated concrete panels by the following method, the specific preparation steps of which are shown below:

[0179] 325 parts of wet-discharged slag ash and 23 parts of first desulfurization gypsum were wet-milled into a slurry to prepare a solid waste slurry with 25% residue on an 80µm sieve and a moisture content of 40%.

[0180] The waste from autoclaved aerated concrete (AAC) products exists as an aqueous suspension of AAC nanoparticles with a solid content of 15%, wherein the mass of the composite activator is 0.01% of the mass of the AAC waste. Solid waste slurry is added to a casting mixer, followed by the sequential addition of 15 parts of the AAC nanoparticle aqueous suspension, 25 parts of an inorganic hydrophobic agent, 15 parts of an organic hydrophobic agent, 2 parts of an ionic liquid mineralizer, and 2 parts of a polycarboxylate superplasticizer, and stirred for 120 seconds. Then, 50 parts of solid waste-based cementitious material and 55 parts of lime are added to the casting mixer, and stirred for 50 seconds. Finally, 3.3 parts of aluminum powder paste are added to the casting mixer and stirred for 45 seconds to form a casting slurry, which is then poured into a mold.

[0181] The slurry was allowed to stand at a constant temperature of 50℃ for 2.5 hours to allow for initial setting and gas generation, resulting in a green body. The semi-finished green body was then subjected to constant temperature autoclaving in an autoclave. During the heating phase, the steam conduction rate and pressure increase rate within the autoclave were controlled. The pressure inside the autoclave increased from 0 to 0.1 MPa after 60 minutes, then to 0.3 MPa after 50 minutes, then to 0.5 MPa after 30 minutes, and finally to 1.25 MPa after 40 minutes, with the temperature at 201℃, and maintained at the same temperature and pressure for 10 hours. After the constant temperature and pressure period ended, the steam conduction rate and pressure reduction rate were controlled, and the pressure decreased to 0.3 MPa after 3 hours.

[0182] After the steam introduction is completed and the pressure inside the autoclave drops to 0.1 MPa, the steam introduction valve is closed, and the power plant desulfurization flue gas is introduced into the autoclave for 8 minutes to perform carbonization curing treatment on the autoclaved aerated concrete slabs for 2.5 hours.

[0183] An acetic acid aqueous solution with a pH of 4 was prepared by reacting acetic acid and water. Octyltriethoxysilane was then added to the acetic acid aqueous solution to achieve a mass concentration of 1.5%. The mixture was stirred for 30 minutes until the octyltriethoxysilane was completely dissolved and the solution became transparent, thus preparing an octyltriethoxysilane solution. This solution was then sprayed twice onto both the front and back surfaces of an autoclaved aerated concrete (AAC) slab. After natural drying for 24 hours, the low-water-absorption AAC slab of Example 3 was obtained.

[0184] Comparative Example

[0185] This comparative example modifies the autoclaved aerated concrete (AAC) material formulation provided in Example 1. The difference lies in that the solid waste-based cementitious material is replaced with PO425 cement. Without altering other raw material ratios or the process flow, the formulation does not include autoclaved aerated concrete product waste, inorganic hydrophobic agents, organic hydrophobic agents, or ionic liquid mineralizers. The prepared AAC slabs are not subjected to carbonization curing, and their surfaces are not impregnated with n-octyltriethoxysilane.

[0186] The specific preparation steps for the autoclaved aerated concrete panels involved in the comparative example are as follows:

[0187] 300 parts of wet-discharged slag ash and 55 parts of first desulfurization gypsum were wet-milled into a slurry to obtain a solid waste slurry with 15% residue on an 80µm sieve and a moisture content of 35%.

[0188] Add solid waste slurry to the casting mixer, add 45 parts of solid waste-based cementitious material and 60 parts of lime to the casting mixer, stir for 60 seconds, then add 3.5 parts of aluminum powder paste to the casting mixer and stir for 30-50 seconds to form a casting slurry and pour it into the mold.

[0189] The slurry was allowed to stand at a constant temperature of 40℃ for initial setting and gas generation, yielding a green body after 3.5 hours. The green body was then subjected to constant-temperature autoclaving in an autoclave. During the heating phase, the steam conduction rate and pressure increase rate within the autoclave were controlled. After 50 minutes, the pressure inside the autoclave increased from 0 to 0.1 MPa; after another 40 minutes, it increased to 0.3 MPa; after another 20 minutes, it increased to 0.5 MPa; and after another 30 minutes, the pressure reached 1.2 MPa and the temperature reached 195℃. This constant temperature and pressure was maintained for 10 hours. After the constant temperature and pressure period, the steam conduction rate and pressure reduction rate were controlled. After 2.5 hours, the pressure decreased to 0.3 MPa, yielding a comparative example of autoclaved aerated concrete (AAC) slabs.

[0190] Test case

[0191] This test example uses the standard GB / T 15762-2020 "Autoclaved Aerated Concrete Panels" to test the performance of autoclaved aerated concrete panels prepared in Examples 1-3 and the comparative example. The test items and results are shown in Table 1.

[0192] Table 1

[0193]

[0194] As shown in Table 1, compared with the comparative example, the autoclaved aerated concrete panels provided in Examples 1-3 not only have significantly improved compressive strength and flexural strength, but also have significantly reduced 1-day and 3-day water absorption rates, resulting in lower water absorption rates for the autoclaved aerated concrete panels provided in Examples 1-3.

[0195] Application examples

[0196] This application example provides a building structure for use in a bathroom. The building structure includes a horizontal slab and vertical walls, both of which are prepared using autoclaved aerated concrete panels provided in Example 1.

[0197] The horizontal slab has a first receiving groove and a second receiving groove on its surface, and the first end of the vertical wall has a protrusion. The protrusion is accommodated inside the first receiving groove. The second receiving groove and the corresponding positions between the end face of the first end of the vertical wall and the surface of the horizontal slab are filled with waterproof mortar. Furthermore, the joint between the vertical wall and the horizontal slab is filled with waterproof sealant. Additionally, a waterproof primer layer and a waterproof coating layer are sequentially applied to the surfaces of the horizontal slab and the vertical wall, thereby further enhancing the waterproofing effect of the building structure.

[0198] The building structure provided in this application example is a bathroom / toilet room, which is constructed using the following method:

[0199] (1) Horizontal slab installation: Horizontal slabs were prepared using the autoclaved aerated concrete (AAC) panels from Example 1. These slabs were then horizontally mounted on the steel beams, with the ends of the slabs overlapping the steel beams by 9 cm. The slabs were connected to the steel beams using hook bolts, with one end of the hook bolt welded to the beam. Adjacent slabs were connected using polyurethane foam adhesive.

[0200] (2) Horizontal slot cutting: Along the intended installation position on the vertical wall, a slot is cut into the horizontal slot using a slotting device to prepare a first receiving slot and a second receiving slot. The first receiving slot has a width of 6cm and a depth of 3cm. The second receiving slot has a width of 4cm and a depth of 3cm. The interval between the first and second receiving slots is 5cm.

[0201] (3) Vertical wall installation: The vertical wall was prepared using the autoclaved aerated concrete panels of Example 1. The thickness of the main section of the vertical wall is 15cm, and the length of the protrusion at the first end of the vertical wall is 10cm and the width is 5cm.

[0202] A vertical wall is erected on the surface of a horizontal slab, such that the protrusion of the vertical wall is inserted into the first receiving groove of the horizontal slab, and the second receiving groove is located below the lower end face of the vertical wall. The upper end and side of the vertical wall are connected to the steel structural beam and steel structural column respectively through auxiliary connectors.

[0203] (4) Waterproof mortar and sealant filling: Waterproof mortar is filled in two layers and compacted in the second receiving groove and the gap between the vertical wall and the horizontal slab. After the waterproof mortar has cured, the inside corners of the cured waterproof mortar are rounded using silane-modified polyurethane waterproof sealant, with a rounding radius of 50mm. Then, waterproof sealant is applied along the joint between the vertical wall and the horizontal slab, extending 3cm on each side of the joint with a thickness of 2mm. After the waterproof sealant has cured, a waterproof primer water-based polyurethane emulsion is applied to the entire surface of the vertical wall and horizontal slab, with a coating amount of 0.3kg / m². 2 .

[0204] (5) After the waterproof primer has dried, apply the waterproof coating in three coats to form a waterproof layer on the floor and walls. After the first coat of waterproof coating is surface dry, apply the second coat of waterproof coating in a direction perpendicular to the previous coat. After it dries, apply the third coat of waterproof coating. The final thickness of the waterproof coating on the vertical wall is 1.5 mm and the thickness on the horizontal floor is 2 mm.

[0205] The building structure constructed for the corresponding use case and applied to the bathroom was subjected to a 72-hour water tightness test, and no leakage occurred. To date, after more than a year of continuous use, no leakage or mold growth on the interior walls has been found.

[0206] In embodiments of the present invention, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. The term "multiple" refers to two or more unless otherwise expressly defined.

[0207] In the embodiments of this invention, the term "and / or" is merely a description of the relationship between associated objects, indicating that there can be three relationships. For example, A and / or B can represent three situations: A exists alone, A and B exist simultaneously, and B exists alone.

[0208] The above description is merely for the purpose of enabling those skilled in the art to understand the technical solutions of the present invention, and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An autoclaved aerated concrete material, characterized in that, The autoclaved aerated concrete material comprises the following components in parts by weight: Wet slag ash, 300-350 parts; Solid waste-based cementitious materials, 45-55 parts; First desulfurized gypsum, 20-25 parts; Waste from autoclaved aerated concrete products, 2.0~2.5 parts; Inorganic hydrophobic agent, 15-35 parts; Organic hydrophobic agent, 10-20 parts; Ionic liquid mineralizer, 1-3 parts; Lime, 50-60 parts; Polycarboxylate superplasticizer, 1-3 parts; Aluminum powder paste, 3.0~3.5 parts; When the wet-discharged slag ash is used in the preparation of the board material, it exists in the form of slag slurry. The slag slurry has at least one of the following characteristics: moisture content of 35% to 45% and particle size of 15% to 35% residue on an 80 μm sieve. The ionic liquid mineralizer includes a bicarbonate, the chemical structural formula of which is shown below: wherein Z + is a 2-methylimidazolium chloride salt cation, a 4-methylimidazolium chloride salt cation, a 2- ethylimidazolium chloride salt cation, or a 4- ethylimidazolium chloride salt cation.

2. The autoclaved aerated concrete material according to claim 1, characterized in that, The waste from the autoclaved aerated concrete (AAC) products exists in the form of an aqueous suspension of autoclaved aerated nanoparticles during application, and the solid content of the aqueous suspension of autoclaved aerated nanoparticles is 5%-25%. The autoclaved aerated concrete nanoparticle aqueous suspension comprises: autoclaved aerated concrete waste, composite activator and water; The mass of the composite activator is 0.01%-0.05% of the mass of the autoclaved aerated concrete waste. The composite activator comprises triethanolamine, ethylene glycol, sodium silicate, sodium sulfite, glycerol, stearic acid, and sodium hexametaphosphate in a mass ratio of 5~10:5~10:2~5:1~3:1~3:1~3:

1.

3. The autoclaved aerated concrete material according to claim 1, characterized in that, The inorganic hydrophobic agent comprises the following components: A layered mica powder, barium sulfate, and silica aerogel dispersion in a mass ratio of 5~10:1~5:

1.

4. The autoclaved aerated concrete material according to claim 1, characterized in that, The organic hydrophobic agent comprises: polyvinyl alcohol wax powder and pregelatinized starch in a mass ratio of 0.5 to 2:

1.

5. An autoclaved aerated concrete (AAC) panel, characterized in that, The autoclaved aerated concrete (AAC) panels are prepared using the autoclaved aerated concrete material as described in any one of claims 1-4.

6. The autoclaved aerated concrete (AAC) panel according to claim 5, characterized in that, The autoclaved aerated concrete slabs are prepared by a constant temperature autoclaving process. After the constant temperature autoclaving process is completed, the autoclaved aerated concrete slab is subjected to carbonation treatment and / or surface hydrophobic treatment.

7. A building structure, characterized in that, The building structure includes a horizontal slab and a vertical wall, both of which are prepared using autoclaved aerated concrete panels as described in claim 5 or 6. The surface of the horizontal slab has a first receiving groove and a second receiving groove. The first end of the vertical wall has a protrusion, which is accommodated inside the first receiving groove. The second receiving groove and the corresponding positions between the end face of the first end of the vertical wall and the surface of the horizontal slab are filled with waterproof mortar. The joint between the vertical wall and the horizontal slab is sealed with waterproof sealant.

8. The building structure according to claim 7, characterized in that, The surfaces of both the horizontal slab and the vertical wall have a waterproof primer layer and a waterproof coating layer arranged sequentially.

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