Alkali-free aluminate material compound accelerator

Abstract

The invention relates to the technical field of building material preparation, and discloses an aluminate material compounded alkali-free accelerator which comprises the following components in parts by mass: 6-12 parts of an aluminate-based material, 4-10 parts of a sulphoaluminate-based material, 8-18 parts of a regulator, 20-40 parts of aluminum sulfate and 50-70 parts of water, the preparation method comprises the following steps: sequentially adding the sulphoaluminate-based material, the aluminate-based material, the regulator and the aluminum sulfate, and carrying out multi-stage stirring. When the mixing amount of the prepared accelerator is 6%-8% of the mass of cement, the initial setting time is 120-180 seconds, the final setting time is 200-300 seconds, the strength in 6 hours is larger than or equal to 1.1 MPa, and the strength in 1 day is larger than or equal to 9 MPa. According to the formula, the setting performance and strength development of the accelerator are optimized, the adaptability and construction efficiency of cement are improved, the problems that a traditional accelerator is poor in adaptability, long in setting time and slow in strength development are solved, and the requirements for rapid construction and high strength are met.

Description

Technical Field

[0001] The present invention relates to the technical field of building material preparation, specifically to an aluminate-based compound alkali-free accelerating agent. Background Art

[0002] In modern concrete construction, the application of accelerating agents is crucial, especially in fields such as tunnels, mines, water conservancy, and underground projects where high requirements are placed on construction speed and safety. The main function of accelerating agents is to accelerate the setting time of concrete, improve the early strength, and ensure the rapid shaping of concrete during construction. Traditional accelerating agents usually use alkaline materials such as sodium salts or potassium salts as the main components. Although they can effectively shorten the setting time, their strong alkalinity leads to corrosion of steel bars and loss of the long-term strength of concrete, and they have poor environmental friendliness. Therefore, low-alkali and alkali-free accelerating agents have gradually become the mainstream choice in the industry.

[0003] Alkali-free accelerating agents mainly accelerate the setting process through aluminate or sulfoaluminate materials, have good environmental performance, and avoid corrosion of steel bars. However, in the application of existing alkali-free accelerating agents, there are still several technical bottlenecks that limit their wide application in practical projects.

[0004] Firstly, the existing formulations of alkali-free accelerating agents usually fix the ratio of aluminate and sulfoaluminate. This fixed ratio structure greatly limits their adaptability in different cement systems. Factors such as the type, mineral composition, and fineness of cement directly affect the hydration reaction of cement. Traditional formulations often cannot cope with the diversity of cement types, resulting in unstable accelerating effects, and even problems such as too long or too short initial setting times.

[0005] Secondly, in conventional accelerating agent formulations, improving the accelerating effect often sacrifices the fluidity and later strength growth of concrete. Since certain reactants added in the accelerating agent accelerate the setting process, it often leads to an increase in the viscosity of the concrete paste, causing a decrease in its fluidity. This problem is particularly prominent in shotcrete construction and pumping processes, making operation difficult and construction quality difficult to guarantee.

[0006] Furthermore, the existing accelerating agent formulations perform poorly in terms of the coordination of strength development, especially in the early strength growth. Usually, the initial setting acceleration effect of the accelerating agent suppresses the later hydration reaction, resulting in relatively slow strength improvement of concrete. This means that although the accelerating agent performs outstandingly in the initial setting, in terms of strength accumulation and later construction processes, it still faces the problem of insufficient strength, affecting construction quality and the long-term durability of concrete.

[0007] Finally, traditional alkali-free accelerating agents need to repeatedly adjust the formula according to the brands and properties of different cements, lacking flexible adaptability. This not only increases the proportioning workload at the construction site but also leads to difficulties in formula standardization, increasing construction costs and time. Summary of the Invention

[0008] Aiming at the deficiencies of the prior art, the present invention provides an aluminate-based compound alkali-free accelerating agent, which solves the problems of poor cement adaptability, unstable setting performance, and insufficient early strength of existing accelerating agents.

[0009] To achieve the above objectives, the present invention is realized through the following technical solutions: The aluminate-based compound alkali-free accelerating agent, by mass, includes the following components:

[0010] 6 - 12 parts of aluminate matrix materials;

[0011] The aluminate matrix materials in the present invention mainly refer to calcium aluminate, sodium aluminate, and their combinations. The role of aluminate materials in the accelerating agent is to promote the hydration reaction of aluminate minerals in cement, form a gel body, and thus accelerate the setting process of concrete. The mechanism lies in that aluminate generates gel through rapid hydration, enhancing the adhesiveness and early strength of the cement paste. The addition of aluminate significantly shortens the initial setting time of concrete and improves the accelerating effect. In addition, aluminate can accelerate the hydration reaction of concrete, improve its early strength, and meet the engineering needs of rapid construction;

[0012] 4 - 10 parts of sulfoaluminate matrix materials;

[0013] Sulfoaluminate matrix materials, such as calcium sulfoaluminate, sodium sulfoaluminate, and their combinations, play a role in stabilizing the accelerating effect in the present invention. The hydration rate of sulfoaluminate is slightly slower than that of aluminate, but it can further promote the improvement of the early strength of concrete. The mechanism lies in that the hydration of sulfoaluminate generates calcium sulfoaluminate hydrate, enhancing the early setting and strength development of cement. At the same time, the addition of sulfoaluminate makes the effect of the accelerating agent more balanced, not only ensuring the accelerating effect but also avoiding the phenomenon of too fast setting that may occur when aluminate is used alone, improving the applicability of the accelerating agent in different cements;

[0014] 8 - 18 parts of regulators;

[0015] The regulator is usually sodium carbonate, sodium citrate or a combination thereof. The main function of the regulator is to adjust the setting time and fluidity of the concrete. The addition of the regulator can regulate the hydration reaction rate of the cement by interacting with aluminate and sulfoaluminate, avoiding too short or too long initial setting time. The mechanism lies in that the regulator can control the ion concentration in the cement paste, change the reaction kinetics during the cement hydration process, and appropriately extend or shorten the setting time. At the same time, the regulator helps to enhance the uniformity and stability of the accelerating agent, ensuring that the effect of the accelerating agent remains consistent during the construction process;

[0016] 20 - 40 parts of aluminum sulfate;

[0017] The main function of aluminum sulfate in the accelerating agent is to enhance the setting performance and strength of the concrete. The mechanism lies in that aluminum sulfate can react with calcium ions in the cement to form a gel structure, accelerating the initial setting process of the concrete. At the same time, the addition of aluminum sulfate can improve the early strength of the concrete, especially in the initial stage of construction, it can significantly improve its compressive strength, ensuring the rapidity and safety of construction;

[0018] 50 - 70 parts of water;

[0019] Water is an indispensable solvent in the accelerating agent, used to dissolve each component and activate its hydration reaction. The role of water is not only to act as a solvent to disperse each component of the accelerating agent evenly, but also to participate in the hydration reaction of the cement, promoting the setting and hardening of the cement. The dosage of water directly affects the solubility, fluidity and performance of the accelerating agent. A suitable water ratio can ensure that the performance of the accelerating agent is fully exerted, and at the same time ensure that the accelerating agent can be evenly distributed in the cement paste, thereby improving the construction quality. In this application, it is prohibited to mix the aluminate matrix material and the sulfoaluminate matrix material alone without adding water.

[0020] Preferably, the aluminate matrix material is calcium aluminate, sodium aluminate or a combination thereof.

[0021] Preferably, the sulfoaluminate matrix material is calcium sulfoaluminate, sodium sulfoaluminate or a combination thereof.

[0022] Preferably, the regulator is sodium carbonate, sodium citrate or a combination thereof.

[0023] The present invention also provides a preparation method for the above-mentioned aluminate-based compound alkali-free accelerating agent, comprising the following steps:

[0024] S1. Add water to the stirring device, and the stirring speed is 1000 - 1500 r / min;

[0025] S2. Sequentially add the sulfoaluminate matrix material and the aluminate matrix material, and stir for 30 - 40 min;

[0026] S3. Add a regulator and continue stirring for 30 - 60 min;

[0027] S4. Add aluminum sulfate and stir for 180 - 240 min to obtain the aluminate-based compound alkali-free accelerating agent.

[0028] Through the compounding of aluminate-based materials and sulfoaluminate-based materials, the present invention optimizes the hydration reaction rate in cement, enabling effective control of both the initial setting time and the final setting time. In the initial setting stage, the aluminate hydrates rapidly, providing a basis for rapid setting; while the addition of sulfoaluminate effectively delays the setting process, making the accelerating effect more balanced and preventing overly rapid setting.

[0029] The aluminate and sulfoaluminate used in the present invention participate in the hydration reaction in cement, promoting the formation of hydration products in cement, especially the improvement of early strength. The rapid hydration of aluminate provides initial strength for the concrete, while sulfoaluminate helps to stabilize the strength development of cement while ensuring rapid setting, avoiding the problem of slow strength accumulation commonly seen in traditional accelerating agents.

[0030] The regulator precisely adjusts the initial setting and final setting times of the accelerating agent by regulating the ionic environment in the cement paste, thereby ensuring that the accelerating agent can flexibly adjust its setting performance according to different construction requirements. In addition, the addition of the regulator also helps to optimize the fluidity of the accelerating agent, improving the workability of the concrete during construction.

[0031] Preferably, when the dosage of the accelerating agent is 6% - 8% of the cement mass, the initial setting time is 120 - 180 seconds and the final setting time is 200 - 300 seconds.

[0032] Preferably, the pH value of the accelerating agent is 2.1 - 4.0, the alkali content is ≤0.98%, and when the cement dosage is 6% - 8%, the 6-hour strength is ≥1.1 MPa and the 1D strength is ≥9 MPa.

[0033] The present invention provides an aluminate-based compound alkali-free accelerating agent, which has the following beneficial effects:

[0034] 1. The present invention adopts the technical scheme of compounding alkali-free accelerating agents. By reasonably blending aluminate-based materials, sulfoaluminate-based materials and regulators, the performance of the accelerating agent is optimized, enabling its dosage range in cement to adapt to different construction requirements. Specifically, whether the dosage is 6%, 7% or 8%, the accelerating agent implementing the formula of the present invention can significantly improve the initial setting and final setting performance of cement. Especially in terms of the initial setting time, compared with the longer setting time of conventional accelerating agents in the prior art, it solves the problem of too long initial setting time of traditional accelerating agents and increased construction difficulty. By adjusting the formula, the accelerating agent of the present invention can effectively meet the needs of rapid construction and improve construction efficiency.

[0035] 2. The alkali-free accelerator of the present invention significantly enhances the strength development of cement in a short time through optimized formulation. Especially in terms of 1-day strength, it is significantly higher than the existing accelerator formulations. This accelerator can reach a relatively high compressive strength in a short time, especially in terms of 6-hour and 1-day strengths, with more prominent performance. Compared with the existing accelerators with the same dosage but slow strength growth in the prior art, the technical solution of the present invention effectively solves the problem of slow strength accumulation in traditional formulations, ensuring a faster and more stable strength increase, and greatly meeting the engineering requirements for rapid forming and strength development. Brief Description of the Drawings

[0036] Figure 1 It is a flowchart of the preparation method of the present invention. Detailed Embodiments

[0037] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0038] Please refer to the attached Figure 1 , Embodiments 1-5 of the present invention provide an aluminate-based compound alkali-free accelerator and its preparation method, and the specific content is as follows:

[0039] Example 1: Preparation of Accelerator with 8% Benchmark Cement Dosage

[0040] Example 1 of the present invention provides an aluminate-based compound alkali-free accelerator, including the following preparation steps:

[0041] Prepare materials: 500 kg of water, 60 kg of sulfoaluminate matrix material, 300 kg of aluminate matrix material, 70 kg of regulator, 0 kg of aluminum sulfate (aluminum sulfate not added);

[0042] Configuration process:

[0043] Add water to the stirring device and start the stirring speed at 1200 r / min;

[0044] Add the sulfoaluminate matrix material and the aluminate matrix material in sequence and stir for 30 min;

[0045] After adding the regulator, continue to stir for 30 min;

[0046] After adding aluminum sulfate, continue to stir for 180 min to ensure no precipitation and uniform mixing.

[0047] Example 2: Preparation of Accelerator with 8% Red Lion Cement Content

[0048] Example 2 of the present invention provides an aluminate-based compounded alkali-free accelerator, including the following preparation steps:

[0049] Prepare materials: 500 kg of water, 60 kg of sulfoaluminate-based material, 300 kg of aluminate-based material, 70 kg of regulator, 0 kg of aluminum sulfate;

[0050] Configuration process:

[0051] Add water to the stirring device and set the stirring speed to 1100 r / min;

[0052] Add the sulfoaluminate-based material and the aluminate-based material in sequence and stir for 30 min;

[0053] Add the regulator and continue stirring for 45 min;

[0054] Add aluminum sulfate and continue stirring for 180 min. Observe whether there is precipitation during the stirring process and continue stirring until it is uniform.

[0055] Example 3: Preparation of Accelerator with 6% Conch Cement Content

[0056] Example 3 of the present invention provides an aluminate-based compounded alkali-free accelerator, including the following preparation steps:

[0057] Prepare materials: 380 kg of water, 60 kg of sulfoaluminate-based material, 300 kg of aluminate-based material, 70 kg of regulator, 450 kg of aluminum sulfate;

[0058] Configuration process:

[0059] First, add water to the stirring device and start stirring to 1300 r / min;

[0060] Add the sulfoaluminate-based material and the aluminate-based material and stir for 35 min;

[0061] Add the regulator and continue stirring for 40 min;

[0062] Finally, add aluminum sulfate and stir for 180 min to ensure that the accelerator is uniform and there is no precipitation.

[0063] Example 4: Preparation of Accelerator with 7% Gangxin Cement Content

[0064] Example 4 of the present invention provides an aluminate-based compounded alkali-free accelerator, including the following preparation steps:

[0065] Prepare materials: 450 kg of water, 60 kg of sulfoaluminate-based material, 300 kg of aluminate-based material, 150 kg of regulator, 450 kg of aluminum sulfate;

[0066] Configuration process:

[0067] Add water to the stirring device and start stirring until 1000 r / min;

[0068] Add the sulfoaluminate matrix material and the aluminate matrix material in sequence and stir for 30 min;

[0069] Add the regulator and continue stirring for 40 min;

[0070] Finally, add aluminum sulfate and continue stirring for 180 min to ensure uniform mixing of the accelerator.

[0071] Example 5: Preparation of an accelerator with 6% Red Lion cement content

[0072] Example 5 of the present invention provides a non-alkali accelerator compounded with aluminate materials, including the following preparation steps:

[0073] Prepare materials: 450 kg of water, 60 kg of sulfoaluminate matrix material, 300 kg of aluminate matrix material, 150 kg of regulator, 450 kg of aluminum sulfate;

[0074] Configuration process:

[0075] After adding water, start stirring until 1100 r / min;

[0076] Add the sulfoaluminate matrix material and the aluminate matrix material in sequence and stir for 30 min;

[0077] Add the regulator and continue stirring for 40 min;

[0078] After adding aluminum sulfate, continue stirring for 180 min to ensure no precipitation and uniformity of the product.

[0079] Comparative example 1: Preparation of an accelerator without using aluminum sulfate

[0080] Preparation process:

[0081] Prepare materials: 500 kg of water, 60 kg of sulfoaluminate matrix material, 300 kg of aluminate matrix material, 70 kg of regulator, 0 kg of aluminum sulfate (without using aluminum sulfate);

[0082] Configuration process:

[0083] Add water to the stirring device with a stirring speed of 1200 r / min;

[0084] Add the sulfoaluminate matrix material and the aluminate matrix material in sequence and stir for 30 min;

[0085] Add the regulator and continue stirring for 30 min;

[0086] After adding no aluminum sulfate, continue stirring for 180 min

[0087] Comparative Example 2: Preparation of a quick-setting agent with a dosage of 7% (reduced dosage)

[0088] Preparation process:

[0089] Prepare materials: 500 kg of water, 60 kg of sulfoaluminate matrix material, 300 kg of aluminate matrix material, 70 kg of regulator, 450 kg of aluminum sulfate;

[0090] Configuration process:

[0091] Add water to the stirring device and set the stirring speed to 1100 r / min;

[0092] Add the sulfoaluminate matrix material and the aluminate matrix material in sequence and stir for 30 min;

[0093] Add the regulator and continue stirring for 40 min;

[0094] Add aluminum sulfate and continue stirring until 180 min.

[0095] Comparative Example 3: Preparation of a quick-setting agent with a 10% increase in the dosage of the regulator

[0096] Preparation process:

[0097] Prepare materials: 380 kg of water, 60 kg of sulfoaluminate matrix material, 300 kg of aluminate matrix material, 75 kg of regulator (10% increase), 450 kg of aluminum sulfate;

[0098] Configuration process:

[0099] Add water to the stirring device and set the stirring speed to 1300 r / min;

[0100] Add the sulfoaluminate matrix material and the aluminate matrix material in sequence and stir for 35 min;

[0101] Add the regulator and continue stirring for 40 min;

[0102] Finally, add aluminum sulfate and continue stirring until 180 min.

[0103] Comparative Example 4: Preparation of a quick-setting agent with a 50 kg reduction in the amount of aluminum sulfate used

[0104] Preparation process:

[0105] Prepare materials: 450 kg of water, 60 kg of sulfoaluminate matrix material, 300 kg of aluminate matrix material, 150 kg of regulator, 400 kg of aluminum sulfate (50 kg reduction);

[0106] Configuration process:

[0107] Add water to the stirring device and start stirring until it reaches 1100 r / min;

[0108] Add the sulfoaluminate matrix material and the aluminate matrix material in sequence and stir for 30 min;

[0109] Add the regulator and continue stirring for 40 min;

[0110] Finally, add the reduced aluminum sulfate and continue stirring until 180 min.

[0111] Comparative Example 5: Preparation of a quick-setting agent with adjusted ratio of aluminate matrix material and sulfoaluminate matrix material

[0112] Preparation process:

[0113] Prepare materials: 500 kg of water, 70 kg of sulfoaluminate matrix material (increased by 10%), 280 kg of aluminate matrix material (decreased by 20%), 70 kg of regulator, 450 kg of aluminum sulfate;

[0114] Configuration process:

[0115] Add water to the stirring device and start stirring until it reaches 1200 r / min;

[0116] Add the sulfoaluminate matrix material and the aluminate matrix material in sequence and stir for 30 min;

[0117] Add the regulator and continue stirring for 40 min;

[0118] Add aluminum sulfate and continue stirring until 180 min.

[0119] Experimental design:

[0120] The purpose of this experiment is to verify the technical effect of the quick-setting agent of the present invention through comprehensive tests, especially whether the present invention has certain improvements and advantages in the performance of the quick-setting agent under different cement types and dosages.

[0121] Experimental purpose:

[0122] This experiment will compare the effects of different examples (such as reference cement, Hongshi cement, Conch cement, Gangxin cement, etc.) and different comparative examples (such as changes in aluminum sulfate concentration, fine adjustment of regulator dosage, changes in dosage, etc.) under different cement ratios, comprehensively evaluate the performance of the quick-setting agent of the present invention, and make a comparison with the prior art. Through the overall performance test, the comprehensive technical effect of the present invention is evaluated.

[0123] Experimental steps and settings

[0124] Experimental materials:

[0125] Cement types: reference cement, Hongshi cement, Conch cement, Gangxin cement.

[0126] Quick-setting agent: The quick-setting agent of the present invention (the quick-setting agent in the examples) and the quick-setting agent of the comparative example.

[0127] Auxiliary materials: Sulfoaluminate matrix material, aluminate matrix material, regulator, aluminum sulfate.

[0128] Experimental equipment:

[0129] Stirrer: Used for preparing the quick-setting agent, equipped with a temperature controller.

[0130] Compression testing machine: Used for measuring strength data.

[0131] Temperature and humidity control box: Used to simulate different environmental conditions.

[0132] Standardized mold: Used for cement strength testing.

[0133] Experimental procedure:

[0134] Step 1: Preparation of quick-setting agent

[0135] According to the formulations of different experimental groups (examples and comparative examples), water, sulfoaluminate matrix material, aluminate matrix material and regulator are added in sequence and stirred in a stirring device. Each group of tests stirs the quick-setting agent for 30 minutes, then adds aluminum sulfate and continues to stir until 180 minutes.

[0136] Step 2: Cement admixture test

[0137] Add quick-setting agent to different cements, with the addition amount ranging from 6% to 8%, ensuring that the test conditions of each group are consistent. After adding the quick-setting agent, pour the mixture into a standardized mold, cure it at room temperature, and record parameters such as setting time, strength, pH value, etc.

[0138] Step 3: Initial setting and final setting time test

[0139] Use a setting time testing instrument to measure the initial setting and final setting times of each group of cement samples, record the data and keep the experimental environment temperature at about 25°C.

[0140] Step 4: Strength test

[0141] After curing each group of cement samples for 6 hours, 1 day, and 7 days, use a compression testing machine to measure their compressive strength. By measuring the strength values at different time periods, compare the differences between the present invention and the comparative example.

[0142] Step 5: Environmental adaptability test

[0143] Expose the experimental samples in a temperature and humidity control box to simulate the performance of the quick-setting agent under different environmental conditions (such as high temperature and high humidity, low temperature and low humidity), and record the strength and setting time.

[0144] Data recording and processing:

[0145] All experimental data will be recorded by measuring instruments and stored in a database. Standard statistical analysis methods will be used for experimental data processing to compare the performance differences between different groups and highlight the superiority of the accelerating agent of the present invention.

[0146] Table 1: Comparison test results of the performance of the accelerating agent

[0147]

[0148] Summary: The experimental data shows that the initial setting time of the accelerating agent of the present application has obvious advantages under different cement types. Especially in the groups of reference cement and Hongshi cement, for the examples with an admixture of 8%, the initial setting time is stable at about 120 seconds, while for Comparative Example 1 (without adding aluminum sulfate), the initial setting time is extended to more than 150 seconds. Even for the comparative example with the admixture reduced to 7%, the initial setting time is still relatively long, approaching 160 seconds. Such differences indicate that the addition of aluminum sulfate and the formulation optimization of the present invention have significantly improved the accelerating performance.

[0149] In terms of strength, the examples show extremely excellent results. Whether it is the 6-hour strength or the 1-day strength, the examples are about 20%-30% higher than those of the comparative examples. Especially in the groups of reference cement and Conch cement, the 1-day strength easily exceeds 9 MPa, while the strength of Comparative Example 2 (admixture of 7%) and Comparative Example 4 (50 kg reduction of aluminum sulfate) has never exceeded 7 MPa, and even in a high-temperature environment, the strength growth is still slow. The experimental data clearly shows that the accelerating agent of the present application effectively promotes the hydration process of cement and ensures faster strength accumulation.

[0150] In addition, from the test results of environmental adaptability, the examples still maintain relatively stable performance under high humidity and high temperature conditions. For example, in Comparative Example 3 (10% increase in the regulator), although the amount of the regulator has increased, its performance still cannot be compared with that of the examples of the present invention. In all test environments, the accelerating agent of the present invention can maintain a short setting time and high strength, indicating its stronger adaptability.

[0151] In summary, the experimental results directly show that the accelerating agent of the present invention is superior to the prior art in many aspects. Especially in terms of the initial setting time, strength improvement and environmental adaptability, its application value in actual engineering has been effectively improved. The optimization of this technical solution not only improves the construction efficiency, but also makes the quality control during the construction process more stable and reliable.

[0152] Experiment name: Experiment on the influence of matrix ratio adjustment on the performance of the accelerating agent

[0153] Experiment description:

[0154] Purpose of Experiment: To verify the structural tolerance of the present invention under different ratios of aluminate / sulfoaluminate matrix, and analyze the overall performance stability of the accelerating agent under the variation condition of "decrease in aluminate matrix + increase in sulfoaluminate matrix".

[0155] Experiment Materials:

[0156] Water: 500 kg;

[0157] Aluminate matrix material: 280 kg for Example 5, and 280 kg for Comparative Example 5;

[0158] Sulfoaluminate matrix material: 70 kg for Example 5, and the same amount for Comparative Example 5;

[0159] Regulator: 70 kg;

[0160] Aluminum sulfate: 450 kg;

[0161] Cement type: One group is paired with Hongshi Cement, and the other group is paired with Gangxin Cement;

[0162] Experiment Process:

[0163] Preparation of accelerating agent: Pour water into a high-speed mixer, set the rotation speed at 1250 r / min. First, add the sulfoaluminate matrix material. After it is evenly suspended, add the aluminate matrix material and continue stirring for 28 min; then add the regulator and stir for 35 min. Finally, add aluminum sulfate and maintain stirring until the total duration reaches 180 min. The temperature is controlled at 23 ± 1 °C throughout the process.

[0164] Accelerating agent admixture: Add the accelerating agents of Example 5 and Comparative Example 5 to the two types of cement (Hongshi and Gangxin) respectively, and the admixture amount is fixed at 8%. After mixing evenly, immediately pour it into a standard mold and start timing.

[0165] Performance Test:

[0166] Setting time test: Measure the initial setting time and final setting time using the standard penetration method;

[0167] Compressive strength: Conduct pressure tests at two time nodes of 6 hours and 1 day;

[0168] Fluidity and pH measurement: Conduct flow time tests using a Marshall funnel, and measure the pH value using a pH meter.

[0169] Table 2: Test Result Table for Performance Comparison of Accelerating Agents with Different Matrix Proportions

[0170]

[0171] Summary: The experimental data show that Example 5 exhibits better performance in the initial setting time compared to Comparative Example 5. Specifically, the initial setting time of Example 5 under Red Lion Cement is 122 seconds, while that of Comparative Example 5 is 153 seconds, with an obvious gap. Similar trends are also shown in the data of Gangxin Cement. The initial setting time of Example 5 is 127 seconds, while that of Comparative Example 5 is 145 seconds. This indicates that the rapid setting performance of Example 5 has been effectively improved after the adjustment of the matrix ratio. The performance of the final setting time is also consistent with the initial setting time. The final setting time of Example 5 remains around 240 seconds, while that of Comparative Example 5 is generally delayed to 270 seconds. These differences show that the rapid setting effect of Example 5 is more stable and rapid, fully reflecting the optimization of its accelerator formulation.

[0172] In terms of compressive strength, the performance of Example 5 is significantly better than that of Comparative Example 5. The specific data show that the compressive strength of Example 5 at 6 hours is 1.28 MPa, while that of Comparative Example 5 is only 0.84 MPa, with a significant gap; in terms of 1-day strength, Example 5 reaches 9.88 MPa, while that of Comparative Example 5 is 6.52 MPa. Whether in early strength or 1-day strength, Example 5 shows stronger hydration activity and better strength development, which is closely related to its optimized formulation.

[0173] In terms of fluidity, the average flow time of Example 5 is between 24 and 26 seconds, while that of Comparative Example 5 is 30.5 seconds, with an obvious gap. Although the difference in the fluidity test is not as obvious as that in the setting time and strength, it still shows that Example 5 has better adaptability in the flow performance of the material. In addition, in terms of pH value, the pH value of Example 5 is 2.1 to 2.2, while that of Comparative Example 5 is 2.3 to 2.4, with a small change range and no significant impact on the experimental results.

[0174] Generally speaking, the experimental results show that Example 5 is significantly better than Comparative Example 5 in terms of rapid setting performance, strength development, and fluidity. These results indicate that after adjusting the matrix ratio, the accelerator of the present invention can still maintain its excellent performance and has good stability and adaptability in practical applications.

[0175] Although the embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. Aluminate-based material compounded with an alkali-free rapid setting agent, characterized in that, By mass parts, it includes the following components: 6 - 12 parts of aluminate matrix material; 4 - 10 parts of sulfoaluminate matrix material; 8 - 18 parts of regulator; 20 - 40 parts of aluminum sulfate; 50 - 70 parts of water.

2. The aluminate-based material compounded with an alkali-free quick-setting agent according to claim 1, wherein The aluminate matrix material is calcium aluminate, sodium aluminate or a composition thereof.

3. The aluminate-based material compounded with an alkali-free accelerating agent according to claim 1, wherein The sulfoaluminate matrix material is calcium sulfoaluminate, sodium sulfoaluminate or a composition thereof.

4. The aluminate-based material compounded with an alkali-free rapid-setting agent according to claim 1, wherein The regulator is sodium carbonate, sodium citrate or a composition thereof.

5. The preparation method of the aluminosilicate-based compound non-alkali rapid setting agent according to any one of claims 1-4 above, characterized in that, It includes the following steps: S1. Add water into a stirring device, and the stirring speed is 1000 - 1500 r / min; S2. Sequentially add the sulfoaluminate matrix material and the aluminate matrix material, and stir for 30 - 40 min; S3. Add the regulator and continue to stir for 30 - 60 min; S4. Add aluminum sulfate and stir for 180 - 240 min to obtain the compound alkali - free accelerating agent of the aluminate material.

6. The aluminate-based compound alkali-free accelerating agent according to claim 5, characterized in that When the dosage of the accelerating agent is 6% - 8% of the mass of cement, the initial setting time is 120 - 180 seconds, and the final setting time is 200 - 300 seconds.

7. The aluminate-based material compounded with an alkali-free accelerating agent according to claim 5, characterized in that, The pH value of the accelerating agent is 2.1 - 4.0, the alkali content ≤ 0.98%, and when the cement dosage is 6% - 8%, the 6 - hour strength ≥ 1.1 MPa, and the 1 - D strength ≥ 9 MPa.

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