Airfield pavement autoclaved ceramsite lightweight aggregate concrete mix proportion design method

Abstract

The invention relates to an airport pavement autoclaved ceramsite lightweight aggregate concrete mix proportion design method, and belongs to the technical field of road engineering materials. Comprising the following steps: preparing and pretreating test raw materials; designing a mix proportion; carrying out laboratory preparation; curing the concrete member; and measuring the original performance. Multi-source data are analyzed through intelligent means in combination with conditions such as environment, load and application, the material component proportion is dynamically optimized, and the composite mix proportion design method is formed. The problems that an existing airport pavement is large in thickness, large in resource consumption, low in field construction efficiency, poor in quality, single in pavement material design optimization and the like are solved.

Description

Technical Field

[0001] The invention relates to a mix ratio design method of autoclaved ceramsite lightweight aggregate concrete for airport pavement, and belongs to the technical field of road engineering materials. Background Art

[0002] In recent years, with the surge in my country's air transport volume and the demand for green and low-carbon development, the demand for strength and lightweight airport pavement materials has become increasingly urgent. Lightweight and environmentally friendly concrete and prefabricated assembled components have become research hotspots at this stage.

[0003] Currently, the most widely used airport pavement material is still traditional airport pavement materials (such as ordinary concrete). This material has high density, long construction cycles, and high transportation costs. Although widely used, its shortcomings are also significant, leaving considerable room for improvement. Kunming Changshui International Airport previously used asphalt as a pavement base. Although asphalt is lighter than concrete, the overall structure still relies on a thick base (such as a 32 cm water-stabilized layer), which has limited lightweighting effects. Furthermore, asphalt has a lower compressive strength (approximately 30-40 MPa) than high-performance concrete, and is prone to deformation under long-term high loads, requiring frequent maintenance. Furthermore, asphalt production has high carbon emissions and a significant impact on the environment. Currently, related research fields are exploring the use of polymer materials and high-performance fibers. However, these materials are difficult to prepare and cost, and their recycling process is complex and cumbersome, preventing widespread application. In terms of material design, for example, the technologies disclosed in CN108034450A, a type of AB70 airport pavement asphalt and its preparation method, CN116947374A, a type of asphalt mixture for airport pavements and its preparation method, and CN107892820A, a type of SBS modified asphalt specifically for airport pavements and its preparation method, have relatively little and scattered reference data for the design and development of existing pavement materials, making integration and collaborative optimization difficult. Reference indicators are mostly based on static parameters and cannot respond to dynamic factors such as climate change and load fluctuations in real time. It is difficult to find a balance between performance and environmental protection through manual design alone.

[0004] In summary, existing materials, technologies, and approaches still rely on traditional concrete or metal materials. Polymer materials are not widely used, construction and post-maintenance still have significant shortcomings, and the design methods of material components are limited to a single method. There is an urgent need for intelligent design of lightweight, prefabricated, high-strength materials that also meet material availability and environmental requirements. Summary of the Invention

[0005] To address the aforementioned shortcomings of the existing technologies, the present invention proposes a method for designing the mix proportions of autoclaved ceramsite lightweight aggregate concrete for airport pavements. This pavement material achieves the required strength, skid resistance, and durability while reducing density. Relying on prefabricated technology, it improves construction quality and reduces construction emissions. Furthermore, the intelligent algorithm-assisted composite mix design method enables dynamic, coordinated and optimized design for different regions and conditions, overcoming many of the shortcomings of the existing technologies. This method addresses the existing problems of thick airport pavements, high resource consumption, low on-site construction efficiency, poor quality, and limited pavement material design optimization.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is as follows: A method for designing the mix proportion of autoclaved ceramsite lightweight aggregate concrete for airport pavement comprises the following steps: Step 1: Preparation and pretreatment of experimental raw materials The core components of lightweight aggregate concrete materials include: cement, silica fume, fine aggregate, coarse aggregate and water reducing agent, and the materials are pre-treated; Step 2: Mix design Based on airport temperature and humidity sensors and on-site load conditions, combined with material mechanics data from laboratory tests, a graph neural network (GNN) was used to model the multidimensional relationship between material composition, performance, and environment to design the mix ratio. This process includes multi-source data collection and federated learning system construction, AI model training and initial mix ratio generation, initial mix ratio output and performance prediction, as well as dynamic adjustment and real-time optimization. Step 3: Prepare in the laboratory according to the mix ratio of step 2; Step 4: Curing the concrete components prepared in step 3; Step 5: Measure the original performance of the maintenance component material obtained in step 4.

[0007] Furthermore, in the preparation and pretreatment of the experimental raw materials in step 1: Cement: Ordinary Portland cement is used, with a standard consistency water consumption of 27.8%, an initial setting time of 180 minutes, a final setting time of 320 minutes, a 28-day compressive strength of 44.5 MPa, and a flexural strength of 7.1 MPa; Silica fume: Highly active silica fume is selected, with a SiO2 content of 96.3% and a specific surface area of ​​19.1m² / g, which has the functions of filling pores and enhancing gel formation; Fine aggregate: including natural river sand and pottery sand. Natural river sand is selected from natural river sand with a fineness modulus of 2.83, belonging to Zone II medium sand, an apparent density of 3720kg / m³, and a low moisture content. The pottery sand is selected from autoclaved fine ceramsite with a particle size of 3-6mm, a bulk density of 800-1060kg / m³, a cylinder pressure strength of 6-25MPa, and a 1h water absorption rate of 7%-10%. Coarse aggregate: Autoclaved ceramsite with a particle size of 6-20 mm, an apparent density of 1400-2100 kg / m³, a thermal conductivity of 0.368 W / (m·K), a frost resistance of 1.6%-2.4%, and a softening coefficient of >0.85; Water reducing agent: ATR-M12 polycarboxylic acid water reducing agent is selected, with a water reduction rate of 37%; In addition, it is necessary to prepare a laser particle size analyzer, cement slurry mixer, and constant temperature and humidity curing box corresponding to the above raw materials; The pretreatment includes: screening aggregates, testing crushing value and bulk density, cleaning to remove impurities, mud content ≤1.0%, needle-like flake particles ≤10% and corresponding pretreatment instruments: standard sieve group, crushing value tester, needle-like flake particle tester.

[0008] Furthermore, in the mix ratio design of step 2, the multi-source data collection and federated learning system construction specifically include: Data source: Environmental data: temperature and humidity sensors, weather satellites, load monitors; Material data: autoclaved ceramsite particle size distribution, water absorption, compressive strength; cement type, admixture properties.

[0009] Historical engineering data: airport pavement damage records and repair ratio plans in different climate zones; Federation node configuration: Node types: Airport load and environmental data, autoclaved ceramsite manufacturers’ solid waste sources and process parameters, laboratory mechanical and durability test data; Data security: Local data is encrypted and stored, and only gradient parameters are shared.

[0010] Furthermore, in the mix ratio design of step 2, the AI ​​model training and initial mix ratio generation specifically include: Model Architecture: Input characteristics: autoclaved ceramsite and autoclaved fine ceramsite ratio of 40-70%, cement dosage of 250-400 kg / m³, water reducer type and dosage, and environmental parameters; Algorithm selection: Supervised learning: predicting compressive strength and carbon emissions under different ratios; Reinforcement learning: Dynamically optimize ratio parameters to maximize durability and environmental protection; Federated aggregation strategy: adopts an asynchronous update mechanism to allow nodes to locally optimize according to their own data distribution.

[0011] Furthermore, in the mix ratio design of step 2, the sensor network in the dynamic adjustment and real-time optimization includes: deploying temperature and humidity sensors, stress and strain gauges, and Cl⁻ concentration detectors; and also includes an edge computing terminal for real-time data analysis and triggering mix ratio adjustment instructions.

[0012] Furthermore, in the mix ratio design of step 2, three groups of mix ratios are finally obtained, which follow the following regulations: Group 1: water usage 11.6%, cement usage 26.81%, silica fume usage 2.19%, natural river sand usage 14.26%, autoclaved fine ceramsite usage 11.67%, autoclaved ceramsite 5-10mm usage 11.11%, autoclaved ceramsite 10-15mm usage 22.23%, water reducer usage 0.5%; Group 2: water usage 11.6%, cement usage 26.81%, silica fume usage 2.19%, natural river sand usage 10.37%, autoclaved fine ceramsite usage 15.56%, autoclaved ceramsite 5-10mm usage 11.11%, autoclaved ceramsite 10-15mm usage 22.23%, water reducer usage 0.5%; Group 3: water consumption is 11.6%, cement consumption is 26.81%, silica fume consumption is 2.19%, natural river sand consumption is 6.48%, autoclaved fine ceramsite consumption is 19.45%, autoclaved ceramsite consumption of 5-10mm is 11.11%, autoclaved ceramsite consumption of 10-15mm is 22.23%, and water reducer consumption is 0.5%.

[0013] Furthermore, the laboratory preparation in step 3 specifically includes the following steps: ① Gradient stirring First-stage dry mixing: cement + fiber + 30% water, stirring at high speed for 90 seconds using a forced mixer to ensure uniform dispersion of the fiber; Secondary aggregate mixing: add autoclaved ceramsite, autoclaved fine ceramsite aggregate and mineral admixtures, wet mix for 120 seconds, and use an infrared thermometer to control the temperature ≤30℃; Level 3 fine mixing: inject water reducer and remaining water, stir at low speed for 180s, and use air content meter to measure the air content to 3.5±0.5%; ②Test piece forming Mould specifications: including flexural test pieces and compression test pieces; Perform vibration compaction operation: vibrate on a vibration table for 15-20 seconds, with an amplitude of 0.5mm and a frequency of 50Hz to avoid segregation, and smoothen with a smoothing tool.

[0014] Furthermore, in the fourth step, a steam curing box, a constant temperature and humidity curing box, and a temperature and humidity recorder are used to cure the concrete component prepared in the third step, specifically including: Initial setting stage: Steam curing: 60±5℃, RH≥95%, 8h, to accelerate early strength development; Final setting stage: constant temperature and humidity curing: 20±2℃, RH≥90% for 28 days, simulating the heat storage effect of phase change materials.

[0015] Furthermore, in the step five, the original performance of the maintenance component material obtained in the step four is tested, including: compressive strength, flexural strength, chloride ion penetration resistance test, impact resistance test, frost resistance test and wear resistance test.

[0016] Furthermore, in step five: ① Compressive strength: A uniaxial compression test was conducted on the specimen using an electronic universal testing machine. The specimen was placed flat on the center of the test plate and a load was applied at a loading rate of 1 mm / min. The test was conducted at 3, 7, 14, and 28 days. Three parallel specimens were measured for each test condition, and the average of the test results was taken as the representative compressive strength value under that test condition. ② Flexural strength: The test uses prismatic specimens with a size of 150mm×150mm×600mm. A hydraulic universal testing machine is used to measure the flexural strength of concrete specimens at 3d, 7d, 14d, and 28d of age. ③ Chloride ion penetration resistance test Prepare concrete specimens with a diameter of 100±2mm and a thickness of 50±2mm, and cure them under standard conditions for 28 days or 90 days. Use three specimens as a group during the test. The resistance of concrete to chloride ion penetration is determined by the electric flux value c of the specimen, and its anti-penetration performance is evaluated; Use the step-by-step pressurization method. The water pressure should start from 0.1MPa and then increase by 0.1MPa every 8 hours. Observe the water seepage of the specimen end face at any time. ④Impact resistance test An 8kg steel hammer is released from a height of 300mm and repeatedly impacts the test piece in the form of free fall. The impact test piece is a round pancake with a diameter of 150mm and a thickness of 63.5mm±3mm, with 4 pieces per group. ⑤Frost resistance test The dynamic elastic modulus, mass loss and appearance of concrete specimens after freeze-thaw cycles were measured to characterize the internal damage and surface concrete erosion after freeze-thaw cycles. ⑥ Anti-wear test Used to test the wear resistance of cement concrete. Grind according to the specified wear method, and use the wear amount per unit area on the wear surface of the specimen as a relative indicator for evaluating the wear resistance of cement concrete.

[0017] After adopting the above technical solution, the present invention has at least one of the following beneficial effects compared with the prior art: (1) In response to the demand for lightweight pavement materials, the present invention uses autoclaved ceramsite with a smaller specific gravity to replace the coarse and fine aggregates in traditional concrete materials. The concrete pavement using autoclaved ceramsite has a significantly reduced weight, which is about 23% lower than that of ordinary concrete, making construction more convenient and reducing transportation costs.

[0018] (2) Through intelligent algorithm-assisted composite optimization of material ratios, the "multi-source feature coding" technology is used to encode material properties and environmental parameters into time series features, enhancing the model's generalization ability. With lightweight, high strength, and low carbon emissions as the core goals, a Pareto optimal solution set is constructed. Through data collaboration and dynamic component optimization, the strength and durability of lightweight concrete are guaranteed, and the material strength reaches the level of C45 concrete. The material is adaptable to different regional and environmental requirements and can maintain good performance even in harsh weather conditions and easily corrupted environments such as salt corrosion. This long-term stability further reduces operating costs.

[0019] (3) Breakthrough innovations were achieved through modular prefabrication, high-precision connections, and intelligent construction technology. Using 5m×5m standardized prefabricated panels, with precise factory-controlled reinforcement and steam curing, the panel strength significantly surpassed that of cast-in-place processes. Construction efficiency was significantly improved, and modular replacement was supported, making maintenance and repair easier. Overall performance exceeded airport panel design requirements.

[0020] The core goal of this invention is to solve the key defects of current airport pavement materials in terms of lightweight, strength, construction efficiency and environmental protection through the combination of intelligently designed lightweight and environmentally friendly concrete materials and assembly technology.

[0021] By replacing traditional aggregates with autoclaved ceramsite, this invention reduces the material density by 23% compared to conventional concrete, significantly improving lightweighting. Furthermore, AI-assisted optimization of the composite mix achieves a compressive strength of C45, achieving both lightweight and high-strength requirements, effectively addressing the insufficient strength of asphalt base layers (30-40 MPa). Furthermore, the collaborative design of prefabricated technology and lightweight materials reduces reliance on heavy equipment, enables rapid modular assembly, and adapts to diverse environmental requirements (such as salt corrosion and freeze-thaw zones), addressing the disruption to airport operations caused by traditional construction. Regarding environmental sustainability, using recycled industrial solid waste as raw materials for autoclaved ceramsite allows for simultaneous resource utilization and carbon reduction. Its high durability further reduces the environmental burden by reducing maintenance frequency throughout its lifecycle. While this technology still has room for research on the long-term stability of autoclaved ceramsite, its fatigue resistance under extreme loads, and its adaptability to construction in complex climates, this invention is expected to promote a systematic upgrade of airport pavement construction, from material innovation to construction methods, providing the industry with a next-generation solution that combines high performance, low maintenance, and low carbon footprint. DETAILED DESCRIPTION

[0022] The present invention will be further described in detail below in conjunction with specific implementations to facilitate a clear understanding of the present invention, but they do not constitute a limitation to the present invention.

[0023] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood broadly. For example, they may refer to fixed connections, detachable connections, or integral connections. They may be mechanical or electrical connections. They may be directly connected or indirectly connected through an intermediary. Those skilled in the art will understand the specific meanings of these terms in the present invention based on the specific circumstances.

[0024] A method for designing a mix ratio of autoclaved ceramsite lightweight aggregate concrete for an airport pavement according to this embodiment includes the following steps: Step 1: Preparation and pretreatment of experimental raw materials The core components of lightweight aggregate concrete materials include: cement, silica fume, fine aggregate, coarse aggregate and water reducer, and the materials are pretreated.

[0025] in: Cement: Ordinary Portland cement is used, with a standard consistency water consumption of 27.8%, an initial setting time of 180 minutes, a final setting time of 320 minutes, a 28-day compressive strength of 44.5 MPa, and a flexural strength of 7.1 MPa, meeting high-strength requirements; Silica fume: Highly active silica fume is selected, with a SiO2 content of 96.3% and a specific surface area of ​​19.1m² / g. It has the functions of filling pores and enhancing gel formation, significantly improving compression resistance, impermeability and wear resistance; Fine aggregate: including natural river sand and pottery sand. Natural river sand is selected from natural river sand with a fineness modulus of 2.83, belonging to Zone II medium sand, an apparent density of 3720kg / m³, and low moisture content. The pottery sand is selected from autoclaved fine ceramsite with a particle size of 3-6mm, a bulk density of 800-1060kg / m³, and a cylinder pressure strength of 6-25MPa. It is both lightweight (20%-30% lower than traditional aggregate) and high-strength, with a 1h water absorption rate of 7%-10%; Coarse aggregate: Autoclaved ceramsite is selected, with a particle size of 6-20mm, an apparent density of 1400-2100kg / m³, a thermal conductivity of 0.368W / (m·K), a frost resistance of 1.6%-2.4%, a softening coefficient of >0.85, and excellent fire resistance, earthquake resistance and internal curing properties; Water reducer: ATR-M12 polycarboxylic acid water reducer is used, with a water reduction rate of 37%, which effectively reduces the water-cement ratio and improves the density of concrete; Material synergy advantages: The lightweight design of autoclaved ceramsite, combined with silica fume reinforcement and water-reducing agent optimization, forms a composite system with low density (can be reduced to below 1800kg / m³), high strength (C45 grade compression resistance), and high durability (frost resistance and salt corrosion resistance). It is suitable for the rapid construction and full-life performance requirements of prefabricated pavement. In addition, it is necessary to prepare a laser particle size analyzer, cement slurry mixer, and constant temperature and humidity curing box corresponding to the above raw materials; The pretreatment includes: screening aggregates, testing crushing value and bulk density, cleaning to remove impurities, mud content ≤1.0%, needle-like flake particles ≤10% and corresponding pretreatment instruments: standard sieve group, crushing value tester, needle-like flake particle tester.

[0026] Step 2: Mix design Based on the airport's temperature and humidity sensors and on-site load conditions, combined with the material mechanics data from laboratory tests, the graph neural network (GNN) is used to model the multi-dimensional relationship between material components, performance, and environment, and design the mix ratio. This includes, in sequence, multi-source data collection and federated learning system construction, AI model training and initial mix ratio generation, initial mix ratio output and performance prediction, as well as dynamic adjustment and real-time optimization. The federated learning system is a distributed machine learning framework whose core goal is to achieve cross-institutional and cross-regional data set collaborative training models while protecting data privacy and complying with data security regulations, thereby avoiding the risk of privacy leakage caused by direct data sharing.

[0027] The multi-source data collection and federated learning system construction specifically includes: Data source: Environmental data: temperature and humidity sensors, meteorological satellites (extreme weather warnings), load monitors (frequency of aircraft takeoffs and landings); Material data: autoclaved ceramsite particle size distribution, water absorption, compressive strength; cement type, admixture properties.

[0028] Historical engineering data: airport pavement damage records (cracks, spalling), and repair mix solutions in different climate zones; Federation node configuration: Node types: Airport (load and environmental data), Autoclaved Ceramic Aluminum Producer (solid waste sources and process parameters), Laboratory (mechanical and durability test data).

[0029] Data security: Local data is encrypted and stored, and only gradient parameters are shared (homomorphic encryption); The AI ​​model training and initial ratio generation specifically include: Model Architecture: Input characteristics: autoclaved ceramsite and its proportion (40-70%), cement dosage (250-400kg / m³), admixture type and dosage, and environmental parameters (salt spray concentration, number of freeze-thaw cycles).

[0030] Algorithm selection: Supervised learning (XGBoost / neural network): predicting compressive strength and carbon emissions under different ratios; Reinforcement learning: Dynamically optimize ratio parameters to maximize durability and environmental protection; Federated aggregation strategy: adopts an asynchronous update mechanism to allow nodes to locally optimize according to their own data distribution.

[0031] The sensor network in the dynamic adjustment and real-time optimization includes: deploying temperature and humidity sensors, stress and strain gauges, and Cl⁻ concentration detectors; it also includes edge computing terminals for real-time data analysis and triggering ratio adjustment instructions.

[0032] In this embodiment, according to the above-mentioned mix ratio design method, three groups of mix ratios are finally obtained through training optimization, which follow the following regulations: Group 1: water usage 11.6%, cement usage 26.81%, silica fume usage 2.19%, natural river sand usage 14.26%, autoclaved fine ceramsite usage 11.67%, autoclaved ceramsite 6-10mm usage 11.11%, autoclaved ceramsite 10-15mm usage 22.23%, water reducer usage 0.5%; Group 2: water usage 11.6%, cement usage 26.81%, silica fume usage 2.19%, natural river sand usage 10.37%, autoclaved fine ceramsite usage 15.56%, autoclaved ceramsite 6-10mm usage 11.11%, autoclaved ceramsite 10-15mm usage 22.23%, water reducer usage 0.5%; Group 3: water consumption is 11.6%, cement consumption is 26.81%, silica fume consumption is 2.19%, natural river sand consumption is 6.48%, autoclaved fine ceramsite consumption is 19.45%, autoclaved ceramsite consumption of 6-10mm is 11.11%, autoclaved ceramsite consumption of 10-15mm is 22.23%, and water reducer consumption is 0.5%.

[0033] Step 3: Prepare the mixture in the laboratory according to the mix ratio of step 2, which specifically includes the following steps: ① Gradient stirring First-stage dry mixing: cement + fiber + 30% water, using a forced mixer (speed ≥ 60r / min) for high-speed mixing for 90s to ensure uniform dispersion of the fiber; Secondary aggregate mixing: add autoclaved ceramsite, autoclaved fine ceramsite aggregate and mineral admixtures, wet mix for 120 seconds, and use an infrared thermometer to control the temperature to ≤30℃; Level 3 fine mixing: inject water reducer and remaining water, stir at low speed (speed ≤ 30r / min) for 180s, and use air content meter to measure the air content to 3.5±0.5%; ②Test piece forming Mould specifications: including flexural test piece (150×150×550mm), compression test piece (150mm cube); Perform vibration compaction operation: vibrate on a vibration table for 15-20 seconds, with an amplitude of 0.5mm and a frequency of 50Hz to avoid segregation, and smoothen with a smoothing tool.

[0034] Step 4: Curing the concrete component prepared in step 3. Specifically, this embodiment uses a steam curing box, a constant temperature and humidity curing box, and a temperature and humidity recorder to cure the concrete component prepared in step 3, which specifically includes: Initial setting stage: Steam curing: 60±5℃, RH≥95%, 8h, to accelerate early strength development; Final setting stage: constant temperature and humidity curing: 20±2℃, RH≥90% for 28 days, simulating the heat storage effect of phase change materials.

[0035] Step 5: Measure the original performance of the maintenance component material obtained in step 4.

[0036] Including: compressive strength, flexural strength, chloride ion penetration resistance test, impact resistance test, frost resistance test and wear resistance test.

[0037] ① Compressive strength: An electronic universal testing machine was used to conduct a uniaxial compression test on the specimens. The specimens were placed flat on the center of the testing machine's pressure plate and loaded at a loading rate of 1 mm / min. Tests were conducted at 3, 7, 14, and 28 days. Three parallel specimens were measured for each test condition, and the average of the test results was taken as the representative compressive strength value under that test condition. The measured 28-day compressive strength was 46.12 MPa, reaching the C45 concrete strength (45 MPa ≤ fcu < 50 MPa).

[0038] ② Flexural strength: The test used prismatic specimens with dimensions of 150mm×150mm×600mm. A hydraulic universal testing machine was used to measure the flexural strength of concrete specimens at 3d, 7d, 14d, and 28d. The measured 28d flexural strength was 6Mpa, meeting the airport specification requirement (5Mpa). ③ Chloride ion penetration resistance test Prepare concrete specimens with a diameter of 100±2mm and a thickness of 50±2mm, and cure them under standard conditions for 28 days or 90 days. Use three specimens as a group during the test. The concrete's resistance to chloride ion penetration is determined by the electric flux value c of the specimen, and its anti-penetration performance is evaluated. It is found that Q_s=1049.80C meets the anti-penetration performance requirements; Using the step-by-step pressurization method, the water pressure should start from 0.1MPa, and then increase by 0.1MPa every 8 hours, and observe the water seepage of the specimen end face at any time; the test results meet the P12 requirements.

[0039] ④Impact resistance test An 8kg steel hammer was released from a height of 300mm and repeatedly impacted the test specimens in a free-fall manner. The impact specimens were round pancakes with a diameter of 150mm and a thickness of 63.5mm±3mm, with four specimens per group. The first mix ratio had a failure impact energy of 470.4J, the second mix ratio had a failure impact energy of 305.76J, and the third mix ratio had a failure impact energy of 258.72J. ⑤Frost resistance test The dynamic elastic modulus, mass loss, and appearance of concrete specimens after freeze-thaw cycles were measured to characterize the internal damage and external concrete erosion after freeze-thaw cycles. Each group of parallel specimens consisted of three: for the first and second mix ratios, the mass increased by 0.1% to 0.5% after 300 freeze-thaw cycles, and the relative dynamic elastic modulus of the specimens rose to approximately 106%, indicating high spalling resistance. For the third mix ratio, one specimen shattered after 300 freeze-thaw cycles, and the other two specimens lost 0.6% of their mass. The relative dynamic elastic modulus of the specimens rose to approximately 174%, indicating poor spalling resistance. ⑥ Anti-wear test Used to test the wear resistance of cement concrete. Grind according to the specified wear method, and use the wear loss per unit area on the wear surface of the specimen as a relative indicator for evaluating the wear resistance of cement concrete. The wear loss per unit area of ​​the first, second, and third mix ratios were 0.96 kg / m³, 1.28 kg / m³, and 1.36 kg / m³, respectively.

[0040] The above is merely a preferred embodiment of the present invention and does not constitute any formal limitation on the structure of the present invention. The layout and number of the present invention are not limited to this example and can be optimized according to actual engineering practices. Any modifications, equivalent changes, and decorations to the above embodiment based on the technical principles of the present invention that do not depart from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A method for designing the mix proportion of autoclaved ceramsite lightweight aggregate concrete for airport pavement, characterized in that: The steps include: Step 1: Preparation and pretreatment of experimental raw materials The core components of lightweight aggregate concrete materials include: cement, silica fume, fine aggregate, coarse aggregate and water reducing agent, and the materials are pre-treated; Step 2: Mix design Based on airport temperature and humidity sensors and on-site load conditions, combined with material mechanics data from laboratory tests, a graph neural network (GNN) was used to model the multidimensional relationship between material composition, performance, and environment to design the mix ratio. This process includes multi-source data collection and federated learning system construction, AI model training and initial mix ratio generation, initial mix ratio output and performance prediction, as well as dynamic adjustment and real-time optimization. Step 3: Prepare in the laboratory according to the mix ratio of step 2; Step 4: Curing the concrete components prepared in step 3; Step 5: Measure the original performance of the maintenance component material obtained in step 4.

2. The method for designing the mix ratio of autoclaved ceramsite lightweight aggregate concrete for airport pavement according to claim 1, characterized in that: In the preparation and pretreatment of experimental raw materials in step 1: Cement: Ordinary Portland cement is used, with a standard consistency water consumption of 27.8%, an initial setting time of 180 minutes, a final setting time of 320 minutes, a 28-day compressive strength of 44.5 MPa, and a flexural strength of 7.1 MPa; Silica fume: Highly active silica fume is selected, with a SiO2 content of 96.3% and a specific surface area of ​​19.1m² / g, which has the functions of filling pores and enhancing gel formation; Fine aggregate: including natural river sand and pottery sand. Natural river sand is selected from natural river sand with a fineness modulus of 2.83, belonging to Zone II medium sand, an apparent density of 3720kg / m³, and a low moisture content. The pottery sand is selected from autoclaved fine ceramsite with a particle size of 3-6mm, a bulk density of 800-1060kg / m³, a cylinder pressure strength of 6-25MPa, and a 1h water absorption rate of 7%-10%. Coarse aggregate: Autoclaved ceramsite with a particle size of 6-20 mm, an apparent density of 1400-2100 kg / m³, a thermal conductivity of 0.368 W / (m·K), a frost resistance of 1.6%-2.4%, and a softening coefficient of >0.85; Water reducing agent: ATR-M12 polycarboxylic acid water reducing agent is selected, with a water reduction rate of 37%; In addition, it is necessary to prepare a laser particle size analyzer, cement slurry mixer, and constant temperature and humidity curing box corresponding to the above raw materials; The pretreatment includes: screening aggregates, testing crushing value and bulk density, cleaning to remove impurities, mud content ≤1.0%, needle-like flake particles ≤10% and corresponding pretreatment instruments: standard sieve group, crushing value tester, needle-like flake particle tester.

3. The method for designing the mix ratio of autoclaved ceramsite lightweight aggregate concrete for airport pavement according to claim 2, characterized in that: In the mix ratio design of step 2, the multi-source data collection and federated learning system construction specifically include: Data source: Environmental data: temperature and humidity sensors, weather satellites, load monitors; Material data: autoclaved ceramsite particle size distribution, water absorption, compressive strength; cement type, admixture properties. Historical engineering data: airport pavement damage records and repair ratio plans in different climate zones; Federation node configuration: Node types: Airport load and environmental data, autoclaved ceramsite manufacturers’ solid waste sources and process parameters, laboratory mechanical and durability test data; Data security: Local data is encrypted and stored, and only gradient parameters are shared.

4. The method for designing the mix ratio of autoclaved ceramsite lightweight aggregate concrete for airport pavement according to claim 3, characterized in that: In the mix ratio design of step 2, the AI ​​model training and initial mix ratio generation specifically include: Model Architecture: Input characteristics: autoclaved ceramsite and autoclaved fine ceramsite ratio of 40-70%, cement dosage of 250-400 kg / m³, water reducer type and dosage, and environmental parameters; Algorithm selection: Supervised learning: predicting compressive strength and carbon emissions under different ratios; Reinforcement learning: Dynamically optimize ratio parameters to maximize durability and environmental protection; Federated aggregation strategy: adopts an asynchronous update mechanism to allow nodes to perform local optimization based on their own data distribution.

5. The method for designing the mix ratio of autoclaved ceramsite lightweight aggregate concrete for airport pavement according to claim 3, characterized in that: In the mix ratio design of step 2, the sensor network in the dynamic adjustment and real-time optimization includes: deploying temperature and humidity sensors, stress and strain gauges, and Cl⁻ concentration detectors; and also includes an edge computing terminal for real-time data analysis and triggering mix ratio adjustment instructions.

6. The method for designing the mix ratio of autoclaved ceramsite lightweight aggregate concrete for airport pavement according to claim 5, characterized in that: In the mix ratio design of step 2, three groups of mix ratios are finally obtained, which follow the following regulations: Group 1: water usage 11.6%, cement usage 26.81%, silica fume usage 2.19%, natural river sand usage 14.26%, autoclaved fine ceramsite usage 11.67%, autoclaved ceramsite 5-10mm usage 11.11%, autoclaved ceramsite 10-15mm usage 22.23%, water reducer usage 0.5%; Group 2: water usage 11.6%, cement usage 26.81%, silica fume usage 2.19%, natural river sand usage 10.37%, autoclaved fine ceramsite usage 15.56%, autoclaved ceramsite 5-10mm usage 11.11%, autoclaved ceramsite 10-15mm usage 22.23%, water reducer usage 0.5%; Group 3: water consumption is 11.6%, cement consumption is 26.81%, silica fume consumption is 2.19%, natural river sand consumption is 6.48%, autoclaved fine ceramsite consumption is 19.45%, autoclaved ceramsite consumption of 5-10mm is 11.11%, autoclaved ceramsite consumption of 10-15mm is 22.23%, and water reducer consumption is 0.5%.

7. The method for designing mix proportions of autoclaved ceramsite lightweight aggregate concrete for airport pavement according to claim 5, characterized in that: The laboratory preparation of step 3 specifically includes the following steps: ① Gradient stirring First-stage dry mixing: cement + fiber + 30% water, stirring at high speed for 90 seconds using a forced mixer to ensure uniform dispersion of the fiber; Secondary aggregate mixing: add autoclaved ceramsite, autoclaved fine ceramsite aggregate and mineral admixtures, wet mix for 120 seconds, and use an infrared thermometer to control the temperature ≤30℃; Level 3 fine mixing: inject water reducer and remaining water, stir at low speed for 180s, and use air content meter to measure the air content to 3.5±0.5%; ②Test piece forming Mould specifications: including flexural test pieces and compression test pieces; Perform vibration compaction operation: vibrate on a vibration table for 15-20 seconds, with an amplitude of 0.5mm and a frequency of 50Hz to avoid segregation, and smoothen with a smoothing tool.

8. The method for designing the mix proportion of autoclaved ceramsite lightweight aggregate concrete for airport pavement according to claim 7, characterized in that: In the fourth step, a steam curing box, a constant temperature and humidity curing box, and a temperature and humidity recorder are used to cure the concrete component prepared in the third step, specifically including: Initial setting stage: Steam curing: 60±5℃, RH≥95%, 8h, to accelerate early strength development; Final setting stage: constant temperature and humidity curing: 20±2℃, RH≥90% for 28 days, simulating the heat storage effect of phase change materials.

9. The method for designing the mix ratio of autoclaved ceramsite lightweight aggregate concrete for airport pavement according to claim 8, characterized in that: In the step 5, the original performance of the maintenance component material obtained in the step 4 is tested, including: compressive strength, flexural strength, chloride ion penetration resistance test, impact resistance test, frost resistance test and wear resistance test.

10. The method for designing mix proportion of autoclaved ceramsite lightweight aggregate concrete for airport pavement according to claim 9, characterized in that: In the step 5: ① Compressive strength: A uniaxial compression test was conducted on the specimen using an electronic universal testing machine. The specimen was placed flat on the center of the test plate and a load was applied at a loading rate of 1 mm / min. The test was conducted at 3, 7, 14, and 28 days. Three parallel specimens were measured for each test condition, and the average of the test results was taken as the representative compressive strength value under that test condition. ② Flexural strength: The test uses prismatic specimens with a size of 150mm×150mm×600mm. A hydraulic universal testing machine is used to measure the flexural strength of concrete specimens at 3d, 7d, 14d, and 28d of age. ③ Chloride ion penetration resistance test Prepare concrete specimens with a diameter of 100±2mm and a thickness of 50±2mm, and cure them under standard conditions for 28 days or 90 days. Use three specimens as a group during the test. The resistance of concrete to chloride ion penetration is determined by the electric flux value c of the specimen, and its anti-penetration performance is evaluated; Use the step-by-step pressurization method. The water pressure should start from 0.1 MPa and then increase by 0.1 MPa every 8 hours. Observe the water seepage on the end face of the specimen at any time. ④Impact resistance test A steel hammer weighing 8kg is released from a height of 300mm to repeatedly impact the test piece in the form of free fall. The impact test piece is a round pancake with a diameter of 150mm and a thickness of 63.5mm±3mm, with 4 pieces per group. ⑤Frost resistance test The dynamic elastic modulus, mass loss and appearance of concrete specimens after freeze-thaw cycles were measured to characterize the internal damage and surface concrete erosion after freeze-thaw cycles. ⑥ Anti-wear test Used to test the wear resistance of cement concrete. Grind according to the specified wear method, and use the wear amount per unit area on the wear surface of the specimen as a relative indicator for evaluating the wear resistance of cement concrete.