A cold region anti-frost heaving composite phase change energy storage self-insulation clear water concrete wall

Abstract

This invention relates to the field of thermal insulation wall technology, specifically to a cold-region anti-frost heave composite phase change energy storage self-insulating fair-faced concrete wall. From the outside to the inside, it comprises an outer wall, a first plaster layer, an insulation layer, an elastic buffer transition layer, a composite phase change energy storage layer, a second plaster layer, and an inner wall layer. Each adjacent layer is separated by a dedicated adhesive layer. This invention achieves a synergistic improvement in anti-frost heave, thermal insulation, and energy storage temperature regulation through a rational combination of materials and processes for each functional layer. The functions of each component and structure work together and promote each other, comprehensively improving the wall's performance and effectively solving many technical problems existing in current cold-region walls. The composite phase change energy storage layer, made from modified composite phase change materials, utilizes microcapsule phase change materials within it to absorb and release heat during temperature changes, effectively regulating indoor temperature and reducing temperature fluctuations. This solves the problem of traditional walls only providing passive insulation and having poor temperature regulation.

Description

Technical Field

[0001] This invention relates to the field of thermal insulation wall technology, specifically to a cold-region anti-frost heave composite phase change energy storage self-insulating fair-faced concrete wall. Background Technology

[0002] In frigid regions, winters are cold and long, with outdoor temperatures often dropping below -20°C. Large diurnal and seasonal temperature differences and frequent freeze-thaw cycles place stringent demands on the performance of building walls. As a core component of the building envelope, walls not only need excellent thermal insulation to reduce heat loss and heating energy consumption, ensuring indoor comfort, but also superior frost heave resistance to withstand structural damage caused by repeated freeze-thaw cycles.

[0003] Currently, the wall materials and structures used in cold-region buildings still have many shortcomings. Traditional walls often use a structure combining a single insulation material with ordinary concrete. The thermal expansion coefficients of the insulation material and the base wall are quite different. During long-term repeated freeze-thaw cycles and temperature changes, stress concentration is prone to occur between the layers, leading to problems such as cracking, peeling, and hollowing, which seriously affect the integrity and durability of the wall and shorten the service life of the building.

[0004] With the promotion of building energy conservation and green building concepts, the market's performance requirements for cold-region walls are constantly increasing. There is an urgent need for a composite self-insulating fair-faced concrete wall that can effectively solve the above problems, take into account multiple functions such as frost heave prevention, heat preservation, energy storage and temperature regulation, and has a stable structure, good durability, and is suitable for the special environment of cold regions, so as to meet the actual use needs of cold-region buildings and promote the green and sustainable development of the cold-region building industry. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and propose a cold-region anti-freezing and anti-swelling composite phase change energy storage self-insulating fair-faced concrete wall.

[0006] The specific technical solution is as follows: A cold-region anti-frost heave composite phase change energy storage self-insulating fair water concrete wall, which consists of an outer wall, a first plastering layer, an insulation layer, an elastic buffer transition layer, a composite phase change energy storage layer, a second plastering layer, and an inner wall layer from the outside to the inside, with a special adhesive layer between each adjacent layer.

[0007] The composite phase change energy storage layer is made of modified composite phase change material, the insulation layer is made of modified aerogel insulation material, the special adhesive layer is made of anti-freeze-heave modified adhesive, and the elastic buffer transition layer is made of modified polyurethane elastic material.

[0008] Based on a total percentage of 100%, the thickness of each layer should meet the following requirements: exterior wall 25%-41%, first plaster layer 3%-3.2%, insulation layer 16%-20%, elastic buffer transition layer 0.4%-0.5%, composite phase change energy storage layer 15%-16%, second plaster layer 3%-3.2%, and the remaining thickness for interior wall layers. The thickness of the special adhesive layer is 1-3mm, and the total wall thickness is 38-48cm.

[0009] As a further technical solution, the outer wall is made of frost-resistant concrete and has an antifreeze and waterproof coating; the first and second plastering layers are made of antifreeze plastering mortar; and the inner wall layer is made of lightweight thermal insulation concrete.

[0010] As a further technical solution, the method for preparing the composite phase change energy storage layer includes the following steps:

[0011] S1. Preparation of modified composite phase change materials;

[0012] S2. Mix the modified composite phase change material with cement, quartz sand, and antifreeze at a mass ratio of 100:20-30:15-25:3-5 until homogeneous. Add deionized water and stir to form a paste-like mixture. The amount of water added is 16-18% of the total mass of the mixture.

[0013] S3. Pour the paste mixture into the mold, vibrate and compact it, control the vibration frequency to 30-50Hz, and the vibration time to 5-10min to remove internal air bubbles;

[0014] S4. After compaction, the mixture is cured at room temperature for 24-48 hours, and then placed in a constant temperature curing chamber and cured at 20±2℃ and relative humidity ≥90% for 7-14 days. After demolding, the composite phase change energy storage layer blank is obtained.

[0015] S5. Polish the surface of the composite phase change energy storage layer blank to remove burrs and protrusions, and obtain the composite phase change energy storage layer.

[0016] As a further technical solution, the preparation method of the modified composite phase change material includes the following steps:

[0017] S11. Preparation of composite core material: Stearate and paraffin are mixed at a mass ratio of 6-7:3, placed in a constant temperature water bath, and heated and stirred at 50-60℃ until completely melted to obtain composite core material;

[0018] S12. Preparation of modified shell material: Take SiO2 powder, add 5%-8% of its mass of silane coupling agent KH-550, then add an ethanol-water aqueous solution with a volume ratio of 3:1, stir at 40-50℃ for 30-60 min, and carry out hydrophobic modification treatment.

[0019] S13. Microcapsule encapsulation: Modified SiO2 powder is added to the composite core material at a mass ratio of 1:4-5. After stirring evenly, 0.5%-1% of the total mass of the emulsifier Tween-80 is added, and emulsification is carried out at 60-70℃ for 15-25 minutes to form an emulsion. Then, hydrochloric acid is slowly added dropwise to adjust the pH value to 3-4, and the reaction is carried out at 50-60℃ for 2-3 hours to uniformly coat the surface of the composite core material with SiO2 shell material, forming a microcapsule phase change material.

[0020] S14. Enhancement and modification: Take the microcapsule phase change material, add 10%-15% of its mass of carbon fiber and 3%-5% of nano-montmorillonite, and stir in a high-speed mixer at a speed of 800-1000 r / min for 20-30 min.

[0021] S15. Drying and molding: Place the uniformly mixed material into a vacuum drying oven and dry it for 2-3 hours at 70-80℃ and a vacuum degree of -0.08~-0.06MPa to remove moisture and impurities. After cooling to room temperature, pulverize and pass it through an 80-100 mesh sieve to obtain the modified composite phase change material.

[0022] As a further technical solution, the preparation method of the modified aerogel insulation material includes the following steps:

[0023] S21. Aerogel pretreatment: Take silica aerogel powder with a particle size of 1-5μm, put it in an oven, dry it at 100-120℃ for 2-3h to remove the surface adsorbed moisture, and cool it to room temperature for later use.

[0024] S22. Hydrophobic reinforcement modification: The pretreated silica aerogel powder is added to a mixed solution, which is prepared by mixing ethanol, methyltriethoxysilane and deionized water in a volume ratio of 5:2:1. The mass-volume ratio of silica aerogel powder to mixed solution is 1g:10-15mL. Stir at 50-60℃ for 60-90min to form a hydrophobic film of methyltriethoxysilane on the surface of silica aerogel. At the same time, 8%-12% of glass fiber by mass is added, and stirring is continued for 30-40min.

[0025] S23. Molding and curing: Pour the modified mixture into a mold, let it stand at room temperature for 12-24 hours, then put it into a constant temperature drying oven and dry it at 80-90℃ for 4-6 hours. After demolding, the modified aerogel insulation board is obtained.

[0026] S24. Surface treatment: Apply a special adhesive undercoat to both sides of the modified aerogel insulation board.

[0027] As a further technical solution, the preparation method of the antifreeze modified adhesive includes the following steps:

[0028] S31. Mixing of basic components: Cement, quartz sand and fly ash are mixed evenly in a mass ratio of 100:80-100:20-30 to obtain the basic bonding components;

[0029] S32. Antifreeze modification: Add 5%-8% of the antifreeze and 3%-5% of the polycarboxylate superplasticizer by mass to the base bonding component and stir evenly; the urea antifreeze is made by mixing urea and calcium nitrate in a mass ratio of 3:2.

[0030] S33. Flexible modification: Add 2%-4% by weight of ethylene-vinyl acetate copolymer latex powder and stir evenly;

[0031] S34. Preparation and molding: Add deionized water and stir until a uniform, lump-free paste is formed. The water-to-binder ratio is 0.4-0.5 to obtain the antifreeze-heave modified adhesive.

[0032] As a further technical solution, the frost-resistant concrete mix ratio of the exterior wall is: cement:sand:stone:water:antifreeze agent = 1:2.3:3.5:0.5:0.03, and the antifreeze agent is a calcium nitrite-sodium sulfate composite antifreeze agent; the thickness of the antifreeze and waterproof coating is 0.3-0.5mm, and it is made by mixing acrylic emulsion, quartz powder and antifreeze agent in a mass ratio of 100:20:5; the sand is medium sand with a fineness modulus of 2.3-3.0, and the stone is crushed stone with a particle size of 5-20mm.

[0033] As a further technical solution, the antifreeze plastering mortar components of the first plastering layer and the second plastering layer are in the following mass ratio: cement: sand: latex powder: antifreeze agent = 1:3:0.05:0.02; the lightweight thermal insulation concrete mix ratio of the inner wall layer is: cement: ceramsite: sand: water: thermal insulation agent = 1:2.0:1.5:0.6:0.02.

[0034] As a further technical solution, the ceramsite is lightweight ceramsite, the heat preservation agent is polystyrene particles, and the antifreeze is a calcium nitrite-sodium sulfate composite antifreeze.

[0035] As a further technical solution, the construction method of the wall includes the following steps:

[0036] Step 1. Substrate preparation: Clean the construction site to ensure the substrate is flat, clean, and free of debris;

[0037] Step 2. Exterior wall construction: Prepare frost-resistant concrete according to the design mix ratio, pour it into shape using formwork, vibrate it to make it dense, and cure it to more than 70% of the design strength. Then remove the formwork, apply an anti-freeze and waterproof coating to the exterior wall surface, and let it dry for later use.

[0038] Step 3. First plastering layer construction: Apply a special adhesive layer evenly to the inner surface of the exterior wall, lay antifreeze plastering mortar, level and compact, and cure for 24-48 hours until the surface is dry;

[0039] Step 4. Insulation layer construction: Apply a special adhesive layer evenly to the surface of the first plaster layer, and tightly attach the modified aerogel insulation board to the first plaster layer to ensure tight adhesion and no air gaps. Cure for more than 24 hours.

[0040] Step 5. Construction of elastic buffer transition layer: Apply a special adhesive layer evenly to the inner surface of the insulation layer, lay the modified polyurethane elastic material evenly, compact it and cure for 12-24 hours until the surface is dry.

[0041] Step 6. Construction of composite phase change energy storage layer: Apply a special adhesive layer evenly to the inner surface of the elastic buffer transition layer, tightly attach the prepared composite phase change energy storage layer blank to the elastic buffer transition layer, compact and fix it, and cure for 12-16 hours.

[0042] Step 7. Construction of the second finishing layer: Apply a special adhesive layer evenly to the inner surface of the composite phase change energy storage layer, lay antifreeze finishing mortar, level and compact, and cure for 24-48 hours until the surface is dry.

[0043] Step 8. Interior wall layer construction: Apply a special adhesive layer evenly to the surface of the second plaster layer, prepare lightweight thermal insulation concrete according to the design mix ratio, pour it into shape, vibrate it to compact it, and cure it for 12-16 hours.

[0044] Step 9. Overall curing: Carry out overall curing of the entire wall for no less than 14 days. During the curing period, control the ambient temperature to be no lower than -10℃ and avoid rain soaking and drastic temperature changes.

[0045] Step 10. Acceptance: After curing is completed, the appearance, thickness, bonding strength, frost heave resistance, and thermal insulation performance of the wall are tested. Construction is completed after the tests are passed.

[0046] Compared with the prior art, the present invention has the following beneficial effects:

[0047] This invention optimizes the wall structure design and rationally combines the materials and processes of each functional layer to achieve a synergistic improvement in frost heave prevention, heat preservation, and energy storage and temperature regulation. The functions of each component and structure work together and promote each other, comprehensively improving wall performance from the microscopic to the macroscopic level, effectively solving many technical problems existing in cold-region walls. Because a composite phase change energy storage layer made of modified composite phase change materials is used, the microcapsule phase change materials inside can absorb and release heat during temperature changes, thereby effectively regulating indoor temperature and reducing indoor temperature fluctuations. This solves the problem that traditional walls can only passively insulate and have poor temperature regulation effects. Simultaneously, the phase change materials, after being modified with SiO2 hydrophobicity and reinforced with carbon fiber and nano-montmorillonite, not only improve their stability and frost resistance, avoiding leakage and aging in long-term freeze-thaw environments, but also enhance the structural strength of the composite phase change energy storage layer, enabling it to better resist freeze-thaw stress erosion, providing a fundamental support for the overall frost heave prevention performance of the wall. The special adhesive layer adopts a frost-resistant modified design, with added antifreeze and flexible modified components. It can maintain high bonding strength even in low-temperature environments, effectively preventing peeling and hollowing between functional layers, ensuring the integrity of the wall, and providing structural protection for the coordinated function of each functional layer.

[0048] Because of the elastic buffer transition layer made of modified polyurethane elastic material, it has good elastic deformation capacity, which can effectively buffer the difference in thermal expansion and contraction between the insulation layer and the composite phase change energy storage layer, alleviate the interlayer stress generated during temperature changes and freeze-thaw cycles, and thus solve the problem of cracking and damage caused by interlayer stress concentration in existing walls. At the same time, the elastic buffer transition layer can also fill the tiny gaps between functional layers, reduce heat conduction channels, and further improve the thermal insulation performance of the wall. The insulation layer uses modified aerogel insulation material, which, after hydrophobic enhancement modification, significantly reduces water absorption, avoiding the decline in insulation performance and frost heave damage caused by water infiltration. Its ultra-low thermal conductivity effectively blocks heat exchange between indoors and outdoors. Combined with the energy storage and temperature regulation function of the composite phase change energy storage layer, it significantly reduces building heating energy consumption. The exterior walls are made of frost-resistant concrete with an anti-freeze and waterproof coating on the outer surface, which effectively blocks outdoor moisture infiltration and freeze-thaw erosion, building the first line of frost protection from the outside of the wall. The interior wall layer uses lightweight insulating concrete, which further improves the overall insulation effect of the wall while ensuring structural strength. All insulation and anti-freeze structures work together to form a comprehensive anti-freeze and insulation protection system. Attached Figure Description

[0049] Figure 1 This is a diagram of a cold-region frost-resistant, anti-freezing, phase-change energy storage, self-insulating fair-faced concrete wall.

[0050] 1. Exterior wall, 2. First plaster layer, 3. Insulation layer, 4. Elastic buffer transition layer, 5. Composite phase change energy storage layer, 6. Second plaster layer, 7. Interior wall layer. Detailed Implementation

[0051] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0052] The cold-region anti-frost heave composite phase change energy storage self-insulating fair-faced concrete wall of the present invention comprises, from the outside to the inside, an outer wall 1, a first plaster layer 2, an insulation layer 3, an elastic buffer transition layer 4, a composite phase change energy storage layer 5, a second plaster layer 6, and an inner wall layer 7, with a dedicated adhesive layer between each adjacent layer. Specifically, the composite phase change energy storage layer 5 is made of modified composite phase change material, the insulation layer 3 is made of modified aerogel insulation material, the dedicated adhesive layer is made of anti-frost heave modified adhesive, and the elastic buffer transition layer 4 is made of modified polyurethane elastic material. Based on a total percentage of 100%, the thickness proportions of each layer should meet the following requirements: 25%-41% for exterior wall 1, 3%-3.2% for the first plaster layer 2, 16%-20% for the insulation layer 3, 0.4%-0.5% for the elastic buffer transition layer 4, 15%-16% for the composite phase change energy storage layer 5, 3%-3.2% for the second plaster layer 6, and the remaining amount for the interior wall layer 7. The thickness of the special adhesive layer is 1-3mm, and the total wall thickness is 38-48cm.

[0053] The exterior wall 1 is made of frost-resistant concrete, and the exterior wall surface is coated with an antifreeze and waterproof layer; the first plaster layer 2 and the second plaster layer 6 are made of antifreeze plastering mortar; the interior wall layer 7 is made of lightweight thermal insulation concrete. The preparation methods of each layer of materials and the wall construction methods are described in detail below, and the technical effects of the present invention are verified through specific embodiments, comparative examples and experiments.

[0054] I. Preparation methods of materials for each layer

[0055] 1.1 Preparation method of composite phase change energy storage layer 5

[0056] The preparation method of the composite phase change energy storage layer 5 includes the following steps:

[0057] S1. Preparation of modified composite phase change materials;

[0058] S2. Mix the modified composite phase change material with cement, quartz sand, and antifreeze at a mass ratio of 100:20-30:15-25:3-5 until homogeneous. Add deionized water and stir to form a paste-like mixture. The amount of water added is 16-18% of the total mass of the mixture.

[0059] S3. Pour the paste mixture into the mold, vibrate and compact it, control the vibration frequency to 30-50Hz, and the vibration time to 5-10min to remove internal air bubbles;

[0060] S4. After compaction, the mixture is cured at room temperature for 24-48 hours, and then placed in a constant temperature curing chamber and cured at 20±2℃ and relative humidity ≥90% for 7-14 days. After demolding, the composite phase change energy storage layer blank is obtained.

[0061] S5. Polish the surface of the composite phase change energy storage layer blank to remove burrs and protrusions, and obtain the composite phase change energy storage layer.

[0062] The preparation method of the modified composite phase change material includes the following steps:

[0063] S11. Preparation of composite core material: Stearate and paraffin are mixed at a mass ratio of 6-7:3, placed in a constant temperature water bath, and heated and stirred at 50-60℃ until completely melted to obtain composite core material;

[0064] S12. Preparation of modified shell material: Take SiO2 powder, add 5%-8% of its mass of silane coupling agent KH-550, then add an ethanol-water aqueous solution with a volume ratio of 3:1, stir at 40-50℃ for 30-60 min, and carry out hydrophobic modification treatment.

[0065] S13. Microcapsule encapsulation: Modified SiO2 powder is added to the composite core material at a mass ratio of 1:4-5. After stirring evenly, 0.5%-1% of the total mass of the emulsifier Tween-80 is added, and emulsification is carried out at 60-70℃ for 15-25 minutes to form an emulsion. Then, hydrochloric acid is slowly added dropwise to adjust the pH value to 3-4, and the reaction is carried out at 50-60℃ for 2-3 hours to uniformly coat the surface of the composite core material with SiO2 shell material, forming a microcapsule phase change material.

[0066] S14. Enhancement and modification: Take the microcapsule phase change material, add 10%-15% of its mass of carbon fiber and 3%-5% of nano-montmorillonite, and stir in a high-speed mixer at a speed of 800-1000 r / min for 20-30 min.

[0067] S15. Drying and molding: Place the uniformly mixed material into a vacuum drying oven and dry it for 2-3 hours at 70-80℃ and a vacuum degree of -0.08~-0.06MPa to remove moisture and impurities. After cooling to room temperature, pulverize and pass it through an 80-100 mesh sieve to obtain the modified composite phase change material.

[0068] 1.2 Preparation method of insulation layer 3

[0069] Insulation layer 3 is made of modified aerogel insulation material, and its preparation method includes the following steps:

[0070] S21. Aerogel pretreatment: Take silica aerogel powder with a particle size of 1-5μm, put it in an oven, dry it at 100-120℃ for 2-3h to remove the surface adsorbed moisture, and cool it to room temperature for later use.

[0071] S22. Hydrophobic reinforcement modification: The pretreated silica aerogel powder is added to a mixed solution, which is prepared by mixing ethanol, methyltriethoxysilane and deionized water in a volume ratio of 5:2:1. The mass-volume ratio of silica aerogel powder to mixed solution is 1g:10-15mL. Stir at 50-60℃ for 60-90min to form a hydrophobic film of methyltriethoxysilane on the surface of silica aerogel. At the same time, 8%-12% of glass fiber by mass is added, and stirring is continued for 30-40min.

[0072] S23. Molding and curing: Pour the modified mixture into a mold, let it stand at room temperature for 12-24 hours, then put it into a constant temperature drying oven and dry it at 80-90℃ for 4-6 hours. After demolding, the modified aerogel insulation board is obtained.

[0073] S24. Surface treatment: Apply a special adhesive undercoat to both sides of the modified aerogel insulation board.

[0074] 1.3 Preparation method of special adhesive layer

[0075] The special adhesive layer is made of a frost-resistant modified adhesive, and its preparation method includes the following steps:

[0076] S31. Mixing of basic components: Cement, quartz sand and fly ash are mixed evenly in a mass ratio of 100:80-100:20-30 to obtain the basic bonding components;

[0077] S32. Antifreeze modification: Add 5%-8% by weight of antifreeze and 3%-5% by weight of polycarboxylate superplasticizer to the base bonding component and stir evenly; the antifreeze is composed of urea and calcium nitrate mixed in a mass ratio of 3:2.

[0078] S33. Flexible modification: Add 2%-4% by weight of ethylene-vinyl acetate copolymer latex powder and stir evenly;

[0079] S34. Preparation and molding: Add deionized water and stir until a uniform, lump-free paste is formed. The water-to-binder ratio is 0.4-0.5 to obtain the antifreeze-heave modified adhesive.

[0080] 1.4 Preparation method of exterior wall 1

[0081] The exterior walls are constructed of frost-resistant concrete with a mix ratio of cement:sand:aggregate:water:antifreeze agent = 1:2.3:3.5:0.5:0.03. The antifreeze agent used is a calcium nitrite-sodium sulfate composite antifreeze agent. The sand used is medium sand with a fineness modulus of 2.3-3.0, and the aggregate is crushed stone with a particle size of 5-20mm. The frost-resistant and waterproof coating on the exterior walls is 0.3-0.5mm thick and is made by mixing acrylic emulsion, quartz powder, and antifreeze agent in a mass ratio of 100:20:5.

[0082] 1.5 Preparation methods of the first plaster layer 2, the second plaster layer 3, and the interior wall layer 7

[0083] The first and second finishing layers (2 and 6) are made of antifreeze finishing mortar, with a component ratio of cement:sand:latex powder:antifreeze agent = 1:3:0.05:0.02 by mass. The interior wall layer (7) is made of lightweight insulating concrete, with a mix ratio of cement:ceramsite:sand:water:insulator = 1:2.0:1.5:0.6:0.02. The ceramsite used is lightweight ceramsite, the insulation agent is polystyrene granules, and the antifreeze agent is a calcium nitrite-sodium sulfate composite antifreeze agent.

[0084] 1.6 Overall Wall Construction Method

[0085] The construction method for this cold-region frost-resistant, phase-change energy storage, self-insulating fair-faced concrete wall includes the following steps:

[0086] Step 1. Substrate preparation: Clean the construction site to ensure the substrate is flat, clean, and free of debris;

[0087] Step 2. Construction of exterior wall 1: Prepare frost-resistant concrete according to the design mix ratio, pour it into shape using formwork, vibrate it to make it dense, and cure it to more than 70% of the design strength. Then remove the formwork, apply an anti-freeze and waterproof coating to the exterior wall surface, and let it dry for later use.

[0088] Step 3. Construction of the first plastering layer 2: Apply a special adhesive layer evenly to the inner surface of the exterior wall, lay antifreeze plastering mortar, level and compact it, and cure for 24-48 hours until the surface is dry;

[0089] Step 4. Construction of insulation layer 3: Apply a special adhesive layer evenly to the surface of the first plaster layer 2, and tightly attach the modified aerogel insulation board to the first plaster layer 2 to ensure tight adhesion and no air gaps. Cure for more than 24 hours.

[0090] Step 5. Construction of elastic buffer transition layer 4: Apply a special adhesive layer evenly to the inner surface of insulation layer 3, lay modified polyurethane elastic material evenly, compact it and cure for 12-24 hours until the surface is dry.

[0091] Step 6. Construction of composite phase change energy storage layer 5: Apply a special adhesive layer evenly to the inner surface of the elastic buffer transition layer 4, tightly attach the prepared composite phase change energy storage layer 5 blank to the elastic buffer transition layer 4, compact and fix it, and cure for 12-16 hours.

[0092] Step 7. Construction of the second plastering layer 6: Apply a special adhesive layer evenly to the inner surface of the composite phase change energy storage layer 5, lay the antifreeze plastering mortar, level and compact it, and cure for 24-48 hours until the surface is dry.

[0093] Step 8. Construction of interior wall layer 7: Apply a special adhesive layer evenly to the surface of the second plaster layer 6, prepare lightweight thermal insulation concrete according to the design mix ratio, pour it into shape, vibrate it to compact it, and cure it for 12-16 hours.

[0094] Step 9. Overall curing: Carry out overall curing of the entire wall for no less than 14 days. During the curing period, control the ambient temperature to be no lower than -10℃ and avoid rain soaking and drastic temperature changes.

[0095] Step 10. Acceptance: After curing is completed, the appearance, thickness, bonding strength, frost heave resistance, and thermal insulation performance of the wall are tested. Construction is completed after the tests are passed.

[0096] In existing technologies, insulated concrete walls typically achieve insulation by inserting insulation layers such as polystyrene boards in the middle of the wall. However, the insulation effect of polystyrene boards alone is relatively limited and cannot withstand complex and changing climates for extended periods, easily leading to a significant decrease in insulation performance over time. This invention effectively solves this problem by incorporating insulation layers and a composite phase change energy storage layer. Furthermore, the elastic buffer transition layer can adapt to stress changes, thereby extending the service life of the insulated fair-faced concrete wall.

[0097] The following are specific examples:

[0098] Example 1:

[0099] 1. Wall thickness percentage (total percentage 100%): exterior wall 25%, first plaster layer 3%, insulation layer 16%, elastic buffer transition layer 0.4%, composite phase change energy storage layer 15%, second plaster layer 3%, interior wall layer allowance, total wall thickness is 40cm; special adhesive layer thickness is 1mm.

[0100] 2. Exterior wall: 0.3mm thick antifreeze and waterproof coating; medium sand with a fineness modulus of 2.3; crushed stone with a particle size of 5mm. Thermal transfer coefficient = thermal conductivity / thickness.

[0101] 3. Preparation of composite phase change energy storage layers:

[0102] (1) Preparation of modified composite phase change material: The mass ratio of butyl stearate to paraffin is 6:3; 5% of the mass of silane coupling agent KH-550 is added to SiO2 powder, and the stirring time is 30 min with ethanol aqueous solution; the mass ratio of SiO2 powder to composite core material is 1:4; the amount of emulsifier Tween-80 added is 0.5% of the total mass, the emulsification temperature is 60℃, and the emulsification time is 15 min; the pH value is adjusted to 3 with hydrochloric acid, the stirring reaction temperature is 50℃, and the reaction time is 2 h; the amount of carbon fiber added is 10% of the mass of microcapsule phase change material, the amount of nano montmorillonite added is 3%, the high-speed stirring speed is 800 r / min, and the stirring time is 20 min; the vacuum drying temperature is 70℃, the vacuum degree is -0.08 MPa, and the drying time is 2 h; after pulverization, it is passed through an 80 mesh sieve.

[0103] (2) Preparation of paste mixture: The mass ratio of modified composite phase change material to cement, quartz sand and antifreeze is 100:20:15:3; the amount of water added is 16% of the total mass of the mixture.

[0104] (3) Vibration compaction: vibration frequency 30Hz, vibration time 5min.

[0105] (4) Curing: Curing at room temperature for 24 hours; constant temperature curing chamber temperature 20±2℃, relative humidity 90%, curing time 7 days.

[0106] 4. Insulation layer preparation:

[0107] (1) Aerogel pretreatment: The particle size of the silica aerogel powder is 1 μm, the oven drying temperature is 100℃, and the drying time is 2h.

[0108] (2) Hydrophobic reinforcement modification: the mass-volume ratio of silica aerogel powder to mixed solution is 1g:10mL; the stirring temperature is 50℃, the first stirring time is 60min; the amount of glass fiber added is 8% of the mass of silica aerogel powder, and the second stirring time is 30min.

[0109] (3) Molding and curing: stand at room temperature for 12 hours; dry in a constant temperature drying oven at 80℃ for 4 hours.

[0110] 5. Preparation of a special adhesive layer:

[0111] (1) Basic component mixing: cement, quartz sand and fly ash in a mass ratio of 100:80:20.

[0112] (2) Antifreeze modification: the amount of antifreeze added is 5% of the mass of the basic binder; the amount of polycarboxylate superplasticizer added is 3%; the mass ratio of urea to calcium nitrate in the antifreeze is 3:2.

[0113] (3) Flexible modification: The amount of ethylene-vinyl acetate copolymer latex powder added is 2% of the mass of the basic binder component.

[0114] (4) Preparation and molding: water-to-binder ratio 0.4.

[0115] 6. First and second plastering layers: The mass ratio of antifreeze plastering mortar components is cement:sand:latex powder:antifreeze agent = 1:3:0.05:0.02; the antifreeze agent used is calcium nitrite-sodium sulfate composite antifreeze agent.

[0116] 7. Interior wall layer: Lightweight thermal insulation concrete mix ratio cement:cement:expanded aggregate:sand:water:insulator = 1:2.0:1.5:0.6:0.02; lightweight expanded aggregate is used, and polystyrene granules are used as the insulation agent.

[0117] 8. Wall construction:

[0118] (1) After the exterior wall has been cured to 70% of its design strength, the formwork is removed, and the antifreeze and waterproof coating is applied and then dried.

[0119] (2) The first plaster layer is cured for 24 hours until the surface is dry; the insulation layer is cured for 24 hours; the elastic buffer transition layer is cured for 12 hours until the surface is dry; the composite phase change energy storage layer is cured for 12 hours; the second plaster layer is cured for 24 hours until the surface is dry; and the interior wall layer is cured for 12 hours.

[0120] (3) The overall maintenance time is 14 days. During the maintenance period, the ambient temperature is controlled at -10℃ to avoid rain soaking and drastic temperature changes.

[0121] (4) Acceptance: The appearance, thickness, bonding strength, anti-frost heave performance and thermal insulation performance of the wall were tested and all met the requirements.

[0122] Example 2:

[0123] 1. Percentage of wall layer thickness (total percentage 100%): exterior wall 41%, first plaster layer 3.2%, insulation layer 20%, elastic buffer transition layer 0.5%, composite phase change energy storage layer 16%, second plaster layer 3.2%, interior wall layer surplus, total wall thickness is 38-48cm; special adhesive layer thickness is 1mm.

[0124] 2. Exterior wall: 0.5mm thick antifreeze and waterproof coating; medium sand with a fineness modulus of 3.0; crushed stone with a particle size of 20mm.

[0125] 3. Preparation of composite phase change energy storage layers:

[0126] (1) Preparation of modified composite phase change material: The mass ratio of butyl stearate to paraffin is 7:3; 8% of the mass of silane coupling agent KH-550 is added to SiO2 powder, and the stirring time is 60 min with ethanol aqueous solution; the mass ratio of SiO2 powder to composite core material is 1:5; the amount of emulsifier Tween-80 added is 1% of the total mass, the emulsification temperature is 70℃, and the emulsification time is 25 min; the pH value is adjusted to 4 with hydrochloric acid, the stirring reaction temperature is 60℃, and the reaction time is 3 h; the amount of carbon fiber added is 15% of the mass of microcapsule phase change material, the amount of nano montmorillonite added is 5%, the high-speed stirring speed is 1000 r / min, and the stirring time is 30 min; the vacuum drying temperature is 80℃, the vacuum degree is -0.06 MPa, and the drying time is 3 h; after pulverization, it is passed through a 100-mesh sieve.

[0127] (2) Preparation of paste mixture: The mass ratio of modified composite phase change material to cement, quartz sand and antifreeze is 100:30:25:5; the amount of water added is 18% of the total mass of the mixture.

[0128] (3) Vibration compaction: vibration frequency 50Hz, vibration time 10min.

[0129] (4) Curing: Curing at room temperature for 48 hours; constant temperature curing chamber temperature 20±2℃, relative humidity 95%, curing time 14 days.

[0130] 4. Insulation layer preparation:

[0131] (1) Aerogel pretreatment: The particle size of the silica aerogel powder is 5μm, the oven drying temperature is 120℃, and the drying time is 3h.

[0132] (2) Hydrophobic reinforcement modification: the mass-volume ratio of silica aerogel powder to mixed solution is 1g:15mL; the stirring temperature is 60℃, the first stirring time is 90min; the amount of glass fiber added is 12% of the mass of silica aerogel powder, and the second stirring time is 40min.

[0133] (3) Molding and curing: Let stand at room temperature for 24 hours; dry in a constant temperature drying oven at 90℃ for 6 hours.

[0134] 5. Preparation of a special adhesive layer:

[0135] (1) Basic component mixing: cement, quartz sand and fly ash in a mass ratio of 100:100:30.

[0136] (2) Antifreeze modification: The amount of antifreeze added is 8% of the mass of the basic binder; the amount of polycarboxylate superplasticizer added is 5%; the mass ratio of urea to calcium nitrate in the antifreeze is 3:2.

[0137] (3) Flexible modification: The amount of ethylene-vinyl acetate copolymer latex powder added is 4% of the mass of the basic binder component.

[0138] (4) Preparation and molding: water-to-binder ratio 0.5.

[0139] 6. First and second plastering layers: The mass ratio of antifreeze plastering mortar components is cement:sand:latex powder:antifreeze agent = 1:3:0.05:0.02; the antifreeze agent used is calcium nitrite-sodium sulfate composite antifreeze agent.

[0140] 7. Interior wall layer: Lightweight thermal insulation concrete mix ratio cement:cement:expanded aggregate:sand:water:insulator = 1:2.0:1.5:0.6:0.02; lightweight expanded aggregate is used, and polystyrene granules are used as the insulation agent.

[0141] 8. Wall construction:

[0142] (1) After the exterior wall has been cured to 75% of its design strength, the formwork is removed, and the antifreeze and waterproof coating is applied and then dried.

[0143] (2) The first plaster layer is cured for 48 hours until the surface is dry; the insulation layer is cured for 26 hours; the elastic buffer transition layer is cured for 24 hours until the surface is dry; the composite phase change energy storage layer is cured for 16 hours; the second plaster layer is cured for 48 hours until the surface is dry; and the interior wall layer is cured for 16 hours.

[0144] (3) The overall maintenance time is 16 days. During the maintenance period, the ambient temperature is controlled at -5℃ to avoid rain soaking and drastic temperature changes.

[0145] (4) Acceptance: The appearance, thickness, bonding strength, anti-frost heave performance and thermal insulation performance of the wall were tested and all met the requirements.

[0146] Example 3:

[0147] 1. Wall thickness percentage (total percentage 100%): exterior wall 30%, first plaster layer 3.1%, insulation layer 18%, elastic buffer transition layer 0.42%, composite phase change energy storage layer 15.5%, second plaster layer 3.1%, interior wall layer allowance, total wall thickness is 38-48cm; special adhesive layer thickness is 1mm.

[0148] 2. Exterior wall: 0.4mm thick antifreeze and waterproof coating; medium sand with a fineness modulus of 2.6; crushed stone with a particle size of 12mm.

[0149] 3. Preparation of composite phase change energy storage layers:

[0150] (1) Preparation of modified composite phase change material: The mass ratio of butyl stearate to paraffin is 6.5:3; 6.5% of the mass of silane coupling agent KH-550 is added to SiO2 powder, and the stirring time of ethanol aqueous solution is 45 min; the mass ratio of SiO2 powder to composite core material is 1:4.5; the amount of emulsifier Tween-80 added is 0.7% of the total mass, the emulsification temperature is 65℃, and the emulsification time is 20 min; the pH value is adjusted to 3.5 with hydrochloric acid, the stirring reaction temperature is 55℃, and the reaction time is 2.5 h; the amount of carbon fiber added is 12% of the mass of microcapsule phase change material, the amount of nano montmorillonite added is 4%, the high-speed stirring speed is 900 r / min, and the stirring time is 25 min; the vacuum drying temperature is 75℃, the vacuum degree is -0.07 MPa, and the drying time is 2.5 h; after pulverization, it is passed through a 90 mesh sieve.

[0151] (2) Preparation of paste mixture: The mass ratio of modified composite phase change material to cement, quartz sand and antifreeze is 100:25:20:4; the amount of water added is 17% of the total mass of the mixture.

[0152] (3) Vibration compaction: vibration frequency 40Hz, vibration time 8min.

[0153] (4) Curing: Curing at room temperature for 36 hours; constant temperature curing chamber temperature 20±2℃, relative humidity 92%, curing time 10 days.

[0154] 4. Insulation layer preparation:

[0155] (1) Aerogel pretreatment: The particle size of the silica aerogel powder is 3μm, the oven drying temperature is 110℃, and the drying time is 2.5h.

[0156] (2) Hydrophobic reinforcement modification: the mass-volume ratio of silica aerogel powder to mixed solution is 1g:12mL; the stirring temperature is 55℃, the first stirring time is 75min; the amount of glass fiber added is 10% of the mass of silica aerogel powder, and the second stirring time is 35min.

[0157] (3) Molding and curing: Let stand at room temperature for 18 hours; dry in a constant temperature drying oven at 85℃ for 5 hours.

[0158] 5. Preparation of a special adhesive layer:

[0159] (1) Basic component mixing: cement, quartz sand and fly ash in a mass ratio of 100:90:25.

[0160] (2) Antifreeze modification: The amount of antifreeze added is 6.5% of the mass of the basic binder component; the amount of polycarboxylate superplasticizer added is 4%; the mass ratio of urea to calcium nitrate in the antifreeze is 3:2.

[0161] (3) Flexible modification: The amount of ethylene-vinyl acetate copolymer latex powder added is 3% of the mass of the basic binder component.

[0162] (4) Preparation and molding: water-to-binder ratio 0.45.

[0163] 6. First and second plastering layers: The mass ratio of antifreeze plastering mortar components is cement:sand:latex powder:antifreeze agent = 1:3:0.05:0.02; the antifreeze agent used is calcium nitrite-sodium sulfate composite antifreeze agent.

[0164] 7. Interior wall layer: Lightweight thermal insulation concrete mix ratio cement:cement:expanded aggregate:sand:water:insulator = 1:2.0:1.5:0.6:0.02; lightweight expanded aggregate is used, and polystyrene granules are used as the insulation agent.

[0165] 8. Wall construction:

[0166] (1) After the exterior wall has been cured to 72% of its design strength, the formwork is removed, and the antifreeze and waterproof coating is applied and then dried.

[0167] (2) The first plaster layer is cured for 36 hours until the surface is dry; the insulation layer is cured for 25 hours; the elastic buffer transition layer is cured for 18 hours until the surface is dry; the composite phase change energy storage layer is cured for 14 hours; the second plaster layer is cured for 36 hours until the surface is dry; and the interior wall layer is cured for 14 hours.

[0168] (3) The overall maintenance time is 15 days. During the maintenance period, the ambient temperature is controlled at -8℃ to avoid rain soaking and drastic temperature changes.

[0169] (4) Acceptance: The appearance, thickness, bonding strength, anti-frost heave performance and thermal insulation performance of the wall were tested and all met the requirements.

[0170] Comparative Example 1:

[0171] The difference between this comparative example and Example 3 is that no elastic buffer transition layer is set. Instead, a special adhesive layer is directly applied to the inner surface of the insulation layer before the composite phase change energy storage layer is bonded together. The material parameters, preparation methods, and wall construction methods of the other layers are completely consistent with those of Example 3.

[0172] Comparative Example 2:

[0173] The difference between this comparative example and Example 3 is that the composite phase change energy storage layer made of modified composite phase change material is not used; instead, an ordinary concrete layer is used. The mix proportion of the ordinary concrete layer is the same as that of the frost-heave-resistant concrete for the exterior wall. The material parameters, preparation methods, and wall construction methods of the other layers are completely the same as those in Example 3.

[0174] Experimental verification:

[0175] Experiment 1: Anti-frost heave performance test;

[0176] The test samples were taken from three examples and two comparative examples of the wall. Three parallel cubic specimens of 100mm × 100mm × wall thickness were prepared for each group.

[0177] Before the test, all samples were placed in a 60℃ drying oven for 24 hours and cooled to room temperature. The initial mass, initial side length and initial compressive strength of each sample were measured and recorded.

[0178] The samples were placed in a high and low temperature test chamber, and the freeze-thaw cycle parameters were set as follows: freezing temperature -20℃, freezing time 4h, thawing temperature 20℃, thawing time 4h, one cycle 8h, and a total of 50 freeze-thaw cycles were performed. After every 10 cycles, the surface moisture of the sample was wiped dry, and the mass and side length were measured and recorded. After 50 cycles, the final mass, final side length, and final compressive strength were measured, and the mass loss rate, linear expansion rate, and compressive strength loss rate were calculated. The average value of three parallel samples was taken as the test result, and the changes in the appearance of the sample were also recorded. The results are as follows:

[0179] Table 1

[0180] Group Quality loss rate (%) Linear expansion rate (%) Compressive strength loss rate (%) Appearance Example 1 0.72 0.13 5.8 The surface is intact, without cracks or peeling, only slightly whitish. Example 2 0.53 0.09 4.1 The surface is intact, without cracks or peeling, and the color remains largely unchanged. Example 3 0.49 0.08 3.5 The surface is intact, without cracks or peeling, and the color remains largely unchanged. Comparative Example 1 2.79 0.57 18.1 The surface has fine cracks, slight peeling in some areas, and severe wear at the edges and corners. Comparative Example 2 2.96 0.63 21.6 The surface is obviously cracked, with a large area of ​​peeling, and the edges and corners are damaged and powdery.

[0181] As can be seen from Table 1, the embodiments have excellent anti-freeze-heave performance.

[0182] Experiment 2: Thermal Insulation Performance Test

[0183] The test samples were taken from the same batch of 3 examples and 2 comparative examples. Three parallel plate-shaped specimens of 300mm×300mm×the designed thickness of the wall were prepared for each group. The surface of the specimens was cleaned and smooth, without burrs or hollow areas.

[0184] The protective hot chamber method was used for testing. The sample was installed between the hot and cold chambers, ensuring a good seal between the sample and the chamber, with no air leakage.

[0185] The hot chamber temperature was set to 20±0.5℃ (simulating indoor environment), and the cold chamber temperature was set to -20±0.5℃ (simulating outdoor environment in cold winter). The equipment was adjusted to bring the system to a steady state (heat flux density fluctuation not exceeding 5%). After 24 hours of stable operation, the heat flux density and the surface temperatures on both sides of the sample were measured and recorded.

[0186] The heat transfer coefficient K of the wall was calculated based on the measurement data. The average value of three parallel samples was taken as the test result. The smaller the heat transfer coefficient K value, the better the thermal insulation performance of the wall. The results are as follows;

[0187] Table 2

[0188] Group <![CDATA[Heat flux density (W / m 2 ).]]> Heat transfer coefficient K value Example 1 10.16 0.254 Example 2 8.89 0.222 Example 3 9.52 0.238 Comparative Example 1 12.05 0.357 Comparative Example 2 14.47 0.412

[0189] As can be seen from Table 2, the embodiments of the present invention have excellent thermal insulation performance.

[0190] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not describe all details exhaustively, nor do they limit the invention to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification.

Claims

1. A cold-region frost-resistant, anti-frost-heave composite phase change energy storage self-insulating fair-faced concrete wall, characterized in that, From the outside to the inside, the structure consists of an outer wall, a first plaster layer, an insulation layer, an elastic buffer transition layer, a composite phase change energy storage layer, a second plaster layer, and an inner wall layer. Each adjacent layer is separated by a dedicated adhesive layer. The composite phase change energy storage layer is made of modified composite phase change material, the insulation layer is made of modified aerogel insulation material, the special adhesive layer is made of anti-freeze-heave modified adhesive, and the elastic buffer transition layer is made of modified polyurethane elastic material. Based on a total percentage of 100%, the thickness of each layer should meet the following requirements: exterior wall 25%-41%, first plaster layer 3%-3.2%, insulation layer 16%-20%, elastic buffer transition layer 0.4%-0.5%, composite phase change energy storage layer 15%-16%, second plaster layer 3%-3.2%, and the remaining thickness for interior wall layers. The thickness of the special adhesive layer is 1-3mm, and the total wall thickness is 38-48cm.

2. The cold-region anti-frost heave composite phase change energy storage self-insulating fair-faced concrete wall according to claim 1, characterized in that, The exterior wall is made of frost-resistant concrete and has an antifreeze and waterproof coating. The first and second plastering layers are made of antifreeze plastering mortar. The interior wall is made of lightweight thermal insulation concrete.

3. The cold-region anti-frost heave composite phase change energy storage self-insulating fair-faced concrete wall according to claim 1, characterized in that, The method for preparing the composite phase change energy storage layer includes the following steps: S1. Preparation of modified composite phase change materials; S2. Mix the modified composite phase change material with cement, quartz sand, and antifreeze at a mass ratio of 100:20-30:15-25:3-5 until homogeneous. Add deionized water and stir to form a paste-like mixture. The amount of water added is 16-18% of the total mass of the mixture. S3. Pour the paste mixture into the mold, vibrate and compact it, control the vibration frequency to 30-50Hz, and the vibration time to 5-10min to remove internal air bubbles; S4. After compaction, the mixture is cured at room temperature for 24-48 hours, and then placed in a constant temperature curing chamber and cured at 20±2℃ and relative humidity ≥90% for 7-14 days. After demolding, the composite phase change energy storage layer blank is obtained. S5. Polish the surface of the composite phase change energy storage layer blank to remove burrs and protrusions, and obtain the composite phase change energy storage layer.

4. The cold-region anti-frost heave composite phase change energy storage self-insulating fair-faced concrete wall according to claim 3, characterized in that, The preparation method of the modified composite phase change material includes the following steps: S11. Preparation of composite core material: Stearate and paraffin are mixed at a mass ratio of 6-7:3, placed in a constant temperature water bath, and heated and stirred at 50-60℃ until completely melted to obtain composite core material; S12. Preparation of modified shell material: Take SiO2 powder, add 5%-8% of its mass of silane coupling agent KH-550, then add an ethanol-water aqueous solution with a volume ratio of 3:1, stir at 40-50℃ for 30-60 min, and carry out hydrophobic modification treatment. S13. Microcapsule encapsulation: Modified SiO2 powder is added to the composite core material at a mass ratio of 1:4-5. After stirring evenly, 0.5%-1% of the total mass of the emulsifier Tween-80 is added, and emulsification is carried out at 60-70℃ for 15-25 minutes to form an emulsion. Then, hydrochloric acid is slowly added dropwise to adjust the pH value to 3-4, and the reaction is carried out at 50-60℃ for 2-3 hours to uniformly coat the surface of the composite core material with SiO2 shell material, forming a microcapsule phase change material. S14. Enhancement and modification: Take the microcapsule phase change material, add 10%-15% of its mass of carbon fiber and 3%-5% of nano-montmorillonite, and stir in a high-speed mixer at a speed of 800-1000 r / min for 20-30 min. S15. Drying and molding: Place the uniformly mixed material into a vacuum drying oven and dry it for 2-3 hours at 70-80℃ and a vacuum degree of -0.08~-0.06MPa to remove moisture and impurities. After cooling to room temperature, pulverize and pass it through an 80-100 mesh sieve to obtain the modified composite phase change material.

5. The cold-region anti-frost heave composite phase change energy storage self-insulating fair-faced concrete wall according to claim 1, characterized in that, The preparation method of the modified aerogel insulation material includes the following steps: S21. Aerogel pretreatment: Take silica aerogel powder with a particle size of 1-5μm, put it in an oven, dry it at 100-120℃ for 2-3h to remove the surface adsorbed moisture, and cool it to room temperature for later use. S22. Hydrophobic reinforcement modification: The pretreated silica aerogel powder is added to a mixed solution, which is prepared by mixing ethanol, methyltriethoxysilane and deionized water in a volume ratio of 5:2:

1. The mass-volume ratio of silica aerogel powder to mixed solution is 1g:10-15mL. Stir at 50-60℃ for 60-90min to form a hydrophobic film of methyltriethoxysilane on the surface of silica aerogel. At the same time, 8%-12% of glass fiber by mass is added, and stirring is continued for 30-40min. S23. Molding and curing: Pour the modified mixture into a mold, let it stand at room temperature for 12-24 hours, then put it into a constant temperature drying oven and dry it at 80-90℃ for 4-6 hours. After demolding, the modified aerogel insulation board is obtained. S24. Surface treatment: Apply a special adhesive undercoat to both sides of the modified aerogel insulation board.

6. The cold-region frost-resistant composite phase change energy storage self-insulating fair-faced concrete wall according to claim 1, characterized in that, The preparation method of the antifreeze modified adhesive includes the following steps: S31. Mixing of basic components: Cement, quartz sand and fly ash are mixed evenly in a mass ratio of 100:80-100:20-30 to obtain the basic bonding components; S32. Antifreeze modification: Add 5%-8% of the antifreeze and 3%-5% of the polycarboxylate superplasticizer by mass to the base bonding component and stir evenly; the urea antifreeze is made by mixing urea and calcium nitrate in a mass ratio of 3:

2. S33. Flexible modification: Add 2%-4% by weight of ethylene-vinyl acetate copolymer latex powder and stir evenly; S34. Preparation and molding: Add deionized water and stir until a uniform, lump-free paste is formed. The water-to-binder ratio is 0.4-0.5 to obtain the antifreeze-heave modified adhesive.

7. The cold-region anti-frost heave composite phase change energy storage self-insulating fair-faced concrete wall according to claim 1, characterized in that, The frost-heave-resistant concrete mix ratio for the exterior wall is: cement:sand:stone:water:antifreeze agent = 1:2.3:3.5:0.5:0.03, and the antifreeze agent is a calcium nitrite-sodium sulfate composite antifreeze agent; the antifreeze and waterproof coating has a thickness of 0.3-0.5mm and is made by mixing acrylic emulsion, quartz powder, and antifreeze agent in a mass ratio of 100:20:5; the sand is medium sand with a fineness modulus of 2.3-3.0, and the stone is crushed stone with a particle size of 5-20mm.

8. The cold-region anti-frost heave composite phase change energy storage self-insulating fair-faced concrete wall according to claim 1, characterized in that, The antifreeze plastering mortar components of the first and second plastering layers are in the following mass ratio: cement:sand:latex powder:antifreeze agent = 1:3:0.05:0.02; the lightweight thermal insulation concrete mix ratio of the inner wall layer is: cement:ceramsite:sand:water:thermal insulation agent = 1:2.0:1.5:0.6:0.

02.

9. The cold-region anti-frost heave composite phase change energy storage self-insulating fair-faced concrete wall according to claim 8, characterized in that, The ceramsite used is lightweight ceramsite, the heat preservation agent is polystyrene particles, and the antifreeze agent is a calcium nitrite-sodium sulfate composite antifreeze agent.

10. The cold-region frost-resistant composite phase change energy storage self-insulating fair-faced concrete wall according to any one of claims 1-9, characterized in that, The construction method for this wall includes the following steps: Step 1. Substrate preparation: Clean the construction site to ensure the substrate is flat, clean, and free of debris; Step 2. Exterior wall construction: Prepare frost-resistant concrete according to the design mix ratio, pour it into shape using formwork, vibrate it to make it dense, and cure it to more than 70% of the design strength. Then remove the formwork, apply an anti-freeze and waterproof coating to the exterior wall surface, and let it dry for later use. Step 3. First plastering layer construction: Apply a special adhesive layer evenly to the inner surface of the exterior wall, lay antifreeze plastering mortar, level and compact, and cure for 24-48 hours until the surface is dry; Step 4. Insulation layer construction: Apply a special adhesive layer evenly to the surface of the first plaster layer, and tightly attach the modified aerogel insulation board to the first plaster layer to ensure tight adhesion and no air gaps. Cure for more than 24 hours. Step 5. Construction of elastic buffer transition layer: Apply a special adhesive layer evenly to the inner surface of the insulation layer, lay the modified polyurethane elastic material evenly, compact it and cure for 12-24 hours until the surface is dry. Step 6. Construction of composite phase change energy storage layer: Apply a special adhesive layer evenly to the inner surface of the elastic buffer transition layer, tightly attach the prepared composite phase change energy storage layer blank to the elastic buffer transition layer, compact and fix it, and cure for 12-16 hours. Step 7. Construction of the second finishing layer: Apply a special adhesive layer evenly to the inner surface of the composite phase change energy storage layer, lay antifreeze finishing mortar, level and compact, and cure for 24-48 hours until the surface is dry. Step 8. Interior wall layer construction: Apply a special adhesive layer evenly to the surface of the second plaster layer, prepare lightweight thermal insulation concrete according to the design mix ratio, pour it into shape, vibrate it to compact it, and cure it for 12-16 hours. Step 9. Overall curing: Carry out overall curing of the entire wall for no less than 14 days. During the curing period, control the ambient temperature to be no lower than -10℃ and avoid rain soaking and drastic temperature changes. Step 10. Acceptance: After curing is completed, the appearance, thickness, bonding strength, frost heave resistance, and thermal insulation performance of the wall are tested. Construction is completed after the tests are passed.

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