Minor clinker cement activator

Abstract

The application discloses a little clinker cement activator and relates to the technical field of cement activators.The application comprises the following steps: step a: preparing an inorganic alkaline activation component: physically mixing anhydrous sodium sulfate and solid sodium silicate with a modulus of 1.0-1.5 at a weight ratio of 3:1-1:1, grinding to a specific surface area of greater than 400 m² / kg, and obtaining composite inorganic activation powder A.The application precisely solves the contradiction between the early strength development and the setting regulation of high-mixed-material cement through the synergy of the inorganic alkaline activation component and the organic setting-regulating component, sodium sulfate (Na2SO4) can quickly dissolve to provide Na⁺ and SO4 2‑ , on the one hand, improves the liquid-phase alkalinity, and activates the glass structure of slag and the like to disintegrate, and on the other hand, quickly reacts with the cement hydration product Ca(OH)2 and the aluminum phase to generate ettringite (AFt), which is the main contributor to the early strength; and the solid sodium silicate (Na2O·nSiO2) with a low modulus provides a continuous and mild alkali activation effect, and ensures the continuous growth of the mid-later strength.

Description

Technical Field

[0001] This invention belongs to the field of cement activator technology, and in particular relates to activators for low-clinker cement. Background Technology

[0002] As the cement industry transforms towards green and low-carbon practices, low-clinker cement has attracted much attention due to its ability to significantly reduce clinker usage and dispose of large amounts of solid waste. However, the introduction of high-proportion active admixtures, while reducing environmental impact, also brings new technical challenges: First, the slow rate of pozzolanic reaction or potential hydraulic reaction of admixtures leads to insufficient early strength development in cement-based materials, making it difficult to meet the strength requirements for rapid construction or demolding of precast components; second, the introduction of single strong alkaline activators to improve early strength often results in concentrated hydration heat release and difficulty in controlling setting time, easily causing excessively rapid loss of workability of fresh grout or subsequent strength reduction; third, the structure and shrinkage characteristics of hydration products in high-admixture systems differ from those of ordinary Portland cement, exhibiting greater drying shrinkage and autogenous shrinkage, higher matrix brittleness, and a tendency to generate microcracks under constrained conditions, affecting the impermeability and long-term durability of the structure.

[0003] Currently, most activators on the market focus on improving a single property, such as simply increasing the alkali content to activate early strength or simply adding fibers to increase toughness. These approaches fail to systematically address the synergistic issues between strength development, setting regulation, volume stability, and crack resistance. Furthermore, traditional activators exhibit poor compatibility with high-dosage blends, easily leading to component segregation or uneven local reactions, affecting the stable performance of the material. Therefore, developing a composite activator that can synergistically optimize the early and late-stage properties of low-clinker cement while balancing workability, strength, and durability has become crucial for promoting the widespread application of low-clinker cement.

[0004] To address these issues, we offer a low-clinker cement activator. Summary of the Invention

[0005] The purpose of this invention is to provide a low-clinker cement activator. Through the composite and synergistic effect of a specific ratio of inorganic alkaline activating components, organic setting regulators and polymer toughening components, it solves the problems of insufficient early strength, difficult setting behavior, easy cracking and poor durability of low-clinker cement in the prior art, as well as the difficulty in balancing performance improvement and cost control.

[0006] To solve the above-mentioned technical problems, the present invention is achieved through the following technical solution.

[0007] This invention is an activator for low-clinker cement, comprising the following steps: Step a: Preparation of inorganic alkaline activating component: Anhydrous sodium sulfate and solid sodium silicate with a modulus of 1.0-1.5 are physically mixed at a weight ratio of 3:1-1:1 and ground until the specific surface area is greater than 400m² / kg to obtain composite inorganic activating powder A; Step b: Preparation of organic-polymer composite components: Sodium gluconate, citric acid and polyvinyl alcohol fibers with an average length of 3-6 mm are dry mixed at a weight ratio of 10:2:1 to obtain composite B; Step c: Mix the composite inorganic activating powder A obtained in step a with the composite B obtained in step b at a weight ratio of 10:1-5:1, and mechanically stir for 10-15 minutes in an environment with humidity less than 30%RH to obtain the composite activator product. Step d: Determine the total amount of admixtures in the low-clinker cementitious materials; the admixtures are at least one of granulated blast furnace slag powder and fly ash; Step e: Based on the total content of the blended materials determined in step d, calculate the amount of composite activator to be added; when the total content of the blended materials is 50%-70% of the total weight of the cementitious materials, the amount of composite activator to be added is 3%-5% of the total weight of the cementitious materials; when the total content of the blended materials is 70%-85% of the total weight of the cementitious materials, the amount of composite activator to be added is 5%-8% of the total weight of the cementitious materials. Step f: The composite activator product prepared in step c, silicate cement clinker, and the mixed material in step d are put into a mixer and dry-mixed for 60-90 seconds; Step g: Add mixing water to the dry mixed material from step f and wet mix for 120-180 seconds to obtain a low-clinker cement paste or mortar containing a composite activator.

[0008] The present invention is further configured such that the grinding in step a is carried out in a planetary ball mill, the grinding media is zirconia balls, and the grinding time is 30-45 minutes.

[0009] The present invention is further configured such that the surface of the polyvinyl alcohol fiber in step b is pretreated with a silane coupling agent KH-550 ethanol solution with a mass concentration of 0.5%-1.0%.

[0010] The present invention is further configured such that the mechanical stirring in step c is carried out in a mixer equipped with a high-speed shear head, and the stirring speed is 800-1200 rpm.

[0011] The present invention is further configured such that the specific surface area of ​​the granulated blast furnace slag powder in step d is greater than 420 m² / kg, and the fly ash is Grade I or Grade II fly ash.

[0012] The present invention is further configured such that the total weight of the cementitious material in step e is the sum of the weights of the silicate cement clinker, the admixture, and the composite activator finished product.

[0013] The present invention is further configured such that the strength grade of the silicate cement clinker in step f is not lower than 52.5.

[0014] The present invention is further configured such that the mixing water in step g contains 0.05%-0.15% redispersible latex powder by weight of the total cementitious material.

[0015] The present invention is further configured such that the water-cement ratio of the low-clinker cement paste obtained in step g is 0.35-0.45.

[0016] The present invention is further configured such that the low-clinker cement paste containing composite activator obtained in step g has an ambient temperature of not less than 5°C.

[0017] The present invention has the following beneficial effects.

[0018] 1. This invention precisely resolves the contradiction between early strength development and setting regulation in high-content blended cement by synergistically combining inorganic alkaline activating components and organic setting-regulating components. Sodium sulfate (Na⁺) can rapidly dissolve to provide Na⁺ and SO₄²⁻. 2- On the one hand, it increases the alkalinity of the liquid phase, stimulating the disintegration of glassy structures such as slag. On the other hand, it reacts rapidly with cement hydration products Ca(OH)2 and the aluminum phase to form ettringite (AFt), which is the main contributor to early strength. Meanwhile, solid sodium silicate (Na2O·nSiO2) with a lower modulus provides a continuous and mild alkaline activation effect, ensuring the continuous growth of strength in the middle and later stages. At the same time, the introduced sodium gluconate and citric acid, as retarding components, have carboxyl groups (-COOH) in their molecules that adsorb onto the surface of cement clinker particles or react with Ca... 2+ Complexation temporarily inhibits the excessively rapid hydration of C3A and C3S, thereby balancing the potentially excessively rapid setting tendency caused by sodium sulfate and ensuring that the freshly mixed slurry has a good workability window. This fine coupling of rapid activation to slow release and strength promotion to setting regulation effectively overcomes the defects of the previous technology where a single activator easily leads to abnormal setting or insufficient early strength.

[0019] 2. This invention introduces surface-treated polyvinyl alcohol (PVA) fibers as a toughening component and integrates them with the activation system, fundamentally improving the crack resistance and durability of low-clinker cement-based materials. High-dosage blended materials have low heat of hydration, large autogenous shrinkage and drying shrinkage, and are prone to microcracks. This technology pre-disperses short-cut PVA fibers as part of the activator in the dry powder. During the mixing process, the fibers can be evenly distributed in the slurry to form a three-dimensional randomized support network. When microcracks initiate and propagate during shrinkage or under stress, the fibers will cross the cracks, transfer stress through bridging, and consume energy, thereby inhibiting crack propagation and significantly improving the toughness, crack resistance, and impermeability of the material. This integrated design from activation to toughening not only solves the problem that traditional activators only focus on strength and ignore the risk of cracking, but also blocks the channels for harmful media to invade by improving the material's density, thereby comprehensively improving the long-term durability of low-clinker cement. Attached Figure Description

[0020] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below.

[0021] Figure 1 This is a flowchart illustrating the preparation process of activators for low-clinker cement.

[0022] Figure 2 Flowchart for the preparation of inorganic alkaline activating components in low-clinker cement activators.

[0023] Figure 3 Flowchart for the preparation of organic-polymer composite components in low-clinker cement activators.

[0024] Figure 4 This is a flowchart of the mixing and post-processing of composite activators in low-clinker cement activators.

[0025] Figure 5 A flowchart illustrating the application of activators and the mixing process of cementitious materials in low-clinker cement activators. Detailed Implementation

[0026] The technical solutions of the present invention will be described below with reference to the accompanying drawings. The described embodiments are only some embodiments of the present invention, and not all embodiments.

[0027] Please see Figures 1-5 This invention is a low-clinker cement activator, comprising the following steps: Step a: Preparation of inorganic alkaline activating component: Anhydrous sodium sulfate and solid sodium silicate with a modulus of 1.0-1.5 are physically mixed at a weight ratio of 3:1-1:1 and ground until the specific surface area is greater than 400m² / kg to obtain composite inorganic activating powder A. The grinding is carried out in a planetary ball mill with zirconia balls as the grinding media and the grinding time is 30-45 minutes. Step b: Preparation of organic-polymer composite components: Sodium gluconate, citric acid and polyvinyl alcohol fibers with an average length of 3-6 mm are dry mixed at a weight ratio of 10:2:1 to obtain composite B. The surface of the polyvinyl alcohol fibers is pretreated with a 0.5%-1.0% mass concentration silane coupling agent KH-550 ethanol solution. Step c: Mix the composite inorganic activating powder A obtained in step a with the composite B obtained in step b at a weight ratio of 10:1-5:1, and mechanically stir for 10-15 minutes in an environment with humidity less than 30%RH to obtain the composite activator product. The mechanical stirring is carried out in a mixer with a high-speed shear head at a stirring speed of 800-1200 rpm. Step d: Determine the total amount of admixtures in the low-clinker cement-based materials; the admixtures are at least one of granulated blast furnace slag powder and fly ash, the specific surface area of ​​the granulated blast furnace slag powder is greater than 420 m² / kg, and the fly ash is Grade I or Grade II fly ash; Step e: Calculate the amount of composite activator to be added based on the total amount of admixtures determined in step d; when the total amount of admixtures is 50%-70% of the total weight of cementitious materials, the amount of composite activator to be added is 3%-5% of the total weight of cementitious materials; when the total amount of admixtures is 70%-85% of the total weight of cementitious materials, the amount of composite activator to be added is 5%-8% of the total weight of cementitious materials. The total weight of cementitious materials is the sum of the weights of silicate cement clinker, admixtures, and the finished composite activator. Step f: The composite activator product prepared in step c, silicate cement clinker, and the mixed material in step d are put into a mixer and dry-mixed for 60-90 seconds. The strength grade of the silicate cement clinker is not lower than 52.5. Step g: Add mixing water to the dry mixed material in step f and wet mix for 120-180 seconds to obtain a low-clinker cement paste or mortar with composite activator. The water-cement ratio of the obtained low-clinker cement paste is 0.35-0.45. The ambient temperature of the obtained low-clinker cement paste with composite activator should not be lower than 5℃.

[0028] Example 1: Application of low-clinker cement activator for precast concrete components Applicable environment: Standard curing workshop of precast component plant, ambient temperature 20℃, used for the production of prestressed concrete beams, slabs and other precast components that require rapid demolding and pursue high early strength.

[0029] Product Description: This is a low-clinker cementitious material for precast components, composed of 52.5 grade silicate cement clinker, S95 grade slag powder, and Grade I fly ash, with a total admixture content of 66.7%. The freshly mixed mortar must have good workability, with an initial setting time of 150-180 minutes; after hardening, the compressive strength should reach over 280% of the benchmark (without activator) within 24 hours, and the strength should reach 80% of the design strength within 3 days, with no cracks on the component surface.

[0030] Performance Comparison Table for Precast Concrete Components The specific steps are as follows: Step 1: Preparation of the composite activator: Anhydrous sodium sulfate and solid sodium silicate with a modulus of 1.2 are physically mixed at a weight ratio of 2:1. The mixture is then ground in a planetary ball mill using zirconia balls as the grinding medium for 35 minutes until the specific surface area is greater than 400 m² / kg, yielding composite inorganic activating powder A. Sodium gluconate, citric acid, and polyvinyl alcohol fibers with an average length of 4 mm are dry-mixed at a weight ratio of 10:2:1 to obtain composite B. Powder A and composite B are mixed at a weight ratio of 8:1. Under conditions of less than 30% RH, the mixture is mechanically stirred at 1000 rpm for 12 minutes using a mixer equipped with a high-speed shear head to obtain the finished composite activator.

[0031] Step 2: Prepare cementitious materials: Weigh 200kg of 52.5 grade silicate cement clinker, 300kg of S95 grade slag powder with a specific surface area of ​​450m² / kg, and 100kg of grade I fly ash, and put them into a mixer to dry mix for 60 seconds.

[0032] Step 3: Calculate and add the activator: The total admixture content is 66.7% of the total weight of the cementitious materials, which is between 50% and 70%. Therefore, the amount of composite activator added is 4.5% of the total weight of the cementitious materials. The total weight of the cementitious materials is the sum of the weights of the silicate cement clinker, admixtures, and the finished composite activator. The calculated mass of the activator is approximately 28.3 kg. Add it to the dry mix from Step 2 and continue dry mixing for 90 seconds.

[0033] Step 4: Prepare the mixing aqueous solution: Dissolve 0.1% of the redispersible latex powder by weight of the total cementitious material in the mixing water beforehand.

[0034] Step 5: Stirring and molding: Add the solution prepared in step 4 to the mixed dry material in step 3, control the water-to-binder ratio to 0.38, and wet mix for 180 seconds to obtain a uniform slurry.

[0035] Step 6: Testing and Molding: The fluidity of the freshly mixed slurry was tested to be 220 mm, the initial setting time was 150 minutes, and the final setting time was 210 minutes. It was then poured into molds and compacted.

[0036] Step 7: Curing and Demolding: Under standard curing conditions of 20℃ (not lower than 5℃), the compressive strength of the component reaches 280% of the reference sample after 24 hours and 80% of the design strength after 3 days, achieving rapid demolding. After demolding, the surface of the component is smooth and free of visible cracks.

[0037] Example 2: Application of activators for on-site casting of large-volume, low-clinker concrete Applicable environment: Summer construction site for large-volume concrete foundations, ambient temperature 30℃, used for large equipment foundations, dam base slabs and other structures that require strict control of hydration temperature rise and drying shrinkage.

[0038] Product Description: This is a cementitious material for large-volume, low-clinker concrete. Its composition includes 52.5 grade silicate cement clinker, slag powder, and Grade II fly ash, with a total admixture content of 78.6%. The concrete pouring temperature must be below 25℃, and the initial setting time must be no less than 180 minutes. After hardening, the maximum internal temperature rise should be at least 15℃ lower than that of traditional silicate cement concrete, and the 28-day drying shrinkage rate should be at least 30% lower.

[0039] Performance Comparison Table for Large-Volume On-Site Cast-in-Place Concrete The specific steps are as follows: Step 1: Preparation of the composite activator: Anhydrous sodium sulfate and solid sodium silicate with a modulus of 1.0 are physically mixed at a weight ratio of 1:1 and ground in a planetary ball mill for 30 minutes to obtain composite inorganic activating powder A. Polyvinyl alcohol fibers are pretreated with a 0.8% (w / w) silane coupling agent KH-550 ethanol solution, and then dry-mixed with sodium gluconate and citric acid at a weight ratio of 10:2:1 to obtain composite B. Powder A and composite B are mixed at a weight ratio of 6:1 and stirred at 900 rpm for 15 minutes in a high-speed shear mixer to obtain the finished composite activator.

[0040] Step 2: Prepare cementitious materials: Weigh 150kg of 52.5 grade silicate cement clinker, 350kg of slag powder with a specific surface area greater than 420m² / kg, and 200kg of grade II fly ash, and put them into a mixer to dry mix for 60 seconds.

[0041] Step 3: Calculate and add activator: The total admixture content is 78.6% of the total weight of the cementitious material, which is between 70% and 85%. Therefore, the amount of composite activator added is 6.5% of the total weight of the cementitious material. Add it to the dry mix from Step 2 and continue dry mixing for 90 seconds.

[0042] Step 4: Prepare low-temperature mixing water: Use an ice-water mixture to lower the temperature of the mixing water to below 5°C.

[0043] Step 5: Stir and control the temperature before pouring into the mold: Add low-temperature mixing water to the dry mixture and stir, control the water-cement ratio, ensure that the concrete outlet temperature meets the standard, and keep the temperature before pouring into the mold below 25℃.

[0044] Step 6: Performance monitoring: The initial setting time of the concrete was measured to be 190 minutes, which meets the requirements for large-area continuous construction.

[0045] Step 7: Monitor temperature rise and shrinkage: Monitoring with pre-embedded sensors showed that the maximum internal temperature rise of the concrete was more than 15°C lower than that of the control group. After 28 days of standard curing, the drying shrinkage rate was tested and found to be 35% lower.

[0046] Example 3: Application of low-cost, low-clinker cement activator for mine backfilling Applicable environments: mine backfilling stations or low-cost mortar preparation sites, used for backfilling materials or low-grade mortars that do not require high early strength but require high waste utilization and good volume stability.

[0047] Product Description: This is a low-clinker cementitious material for mine backfilling. It consists of 52.5 grade silicate cement clinker and steel slag powder with a specific surface area of ​​380 m² / kg, with the total admixture (steel slag powder) comprising 80%. The material is required to have a 28-day compressive strength of not less than 15 MPa, low bleeding rate, good volume stability, and a lower overall cost than traditional cementitious backfilling materials.

[0048] Comparison Table of Performance of Low-Cost Materials for Mine Backfilling The specific steps are as follows: Step 1: Preparation of the composite activator: Anhydrous sodium sulfate and solid sodium silicate with a modulus of 1.5 are physically mixed at a weight ratio of 3:1 and ground in a planetary ball mill for 40 minutes to obtain composite inorganic activating powder A. Sodium gluconate, citric acid, and polyvinyl alcohol fiber are dry-mixed at a weight ratio of 10:2:1 to obtain composite B. Powder A and composite B are mixed at a weight ratio of 5:1 and stirred at 1100 rpm for 10 minutes in a high-speed shear mixer to obtain the finished composite activator.

[0049] Step 2: Prepare cementitious materials: Weigh 100kg of 52.5 grade silicate cement clinker and 400kg of steel slag powder, and put them into the mixer to dry mix for 60 seconds.

[0050] Step 3: Calculate and add the activator: The total amount of the blended material should be 80% of the total weight of the cementitious material, which is between 70% and 85%. Therefore, the amount of composite activator should be the upper limit, i.e., 8% of the total weight of the cementitious material. Add it to the dry mix from Step 2 and continue to dry mix for 90 seconds.

[0051] Step 4: Stirring and pulping: Add mixing water to the mixed dry materials, control the water-cement ratio to 0.45, and wet mix for 120 seconds to obtain a uniform pulp.

[0052] Step 5: Performance Testing: The slurry exhibits low bleeding after settling. After standard curing for 28 days at an ambient temperature not lower than 5℃, the molded specimens achieve a compressive strength of over 15MPa, meeting the strength requirements of the filling material, and demonstrating good volume stability.

[0053] Example 4: Application of high-performance low-clinker cement activator for structural repair and reinforcement Applicable environment: Emergency repair and reinforcement projects for bridges and building structures, for repair mortars requiring ultra-high early strength, excellent bonding performance and extremely low shrinkage.

[0054] Product Description: High-performance low-clinker cementitious material for structural repair, composed of 52.5 grade silicate cement clinker, silica fume, and ultrafine slag powder, with a total admixture content of 50%. The repair mortar is required to have a 2-hour compressive strength greater than 10 MPa, a bond tensile strength to old concrete greater than 2.5 MPa, and a 28-day shrinkage rate less than 0.02%.

[0055] Comparison Table of Performance of High-Performance Materials for Structural Repair and Reinforcement The specific steps are as follows: Step 1: Preparation of the composite activator: Anhydrous sodium sulfate and solid sodium silicate with a modulus of 1.3 are physically mixed at a weight ratio of 2.5:1. The mixture is then ground in a planetary ball mill using zirconia balls as the grinding medium for 45 minutes until the specific surface area is greater than 400 m² / kg, yielding composite inorganic activating powder A. Sodium gluconate, citric acid, and polyvinyl alcohol fiber are dry-mixed at a weight ratio of 10:2:1 to obtain composite B. Powder A and composite B are mixed at a weight ratio of 9:1. Under conditions of less than 30% RH, the mixture is mechanically stirred at 1200 rpm for 15 minutes using a mixer equipped with a high-speed shear head to obtain the finished composite activator.

[0056] Step 2: Prepare cementitious materials: Weigh 250kg of 52.5 grade silicate cement clinker, 50kg of silica fume, and 200kg of ultrafine slag powder with a specific surface area of ​​600m² / kg, and put them into a mixer to dry mix for 90 seconds.

[0057] Step 3: Calculate and add activator: The total amount of the blended material is 50% of the total weight of the cementitious material, which is between 50% and 70%. Therefore, the amount of composite activator added is 3.5% of the total weight of the cementitious material. Add it to the dry mix from Step 2 and continue to dry mix for 120 seconds.

[0058] Step 4: Preparation of modified mixing water: In the mixing water, pre-dissolve 0.15% of the total weight of the cementitious material in redispersible latex powder.

[0059] Step 5: Stirring and preparing the slurry: Add the solution from step 4 to the mixed dry materials, control the water-cement ratio to 0.35, and wet mix for 180 seconds to obtain high-performance repair mortar.

[0060] Step 6: Performance test: The compressive strength of the repair mortar after 2 hours was found to be greater than 10 MPa, the tensile strength of its bond with old concrete was greater than 2.5 MPa, and the drying shrinkage rate after 28 days was less than 0.02%.

[0061] The preferred embodiments of the present invention disclosed above are only for the purpose of illustrating the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to the specific implementation described herein. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can better understand and utilize the present invention.

Claims

1. A low-clinker cement activator, characterized in that: Includes the following steps: Step a: Preparation of inorganic alkaline activating component: Anhydrous sodium sulfate and solid sodium silicate with a modulus of 1.0-1.5 are physically mixed at a weight ratio of 3:1-1:1 and ground until the specific surface area is greater than 400m² / kg to obtain composite inorganic activating powder A; Step b: Preparation of organic-polymer composite components: Sodium gluconate, citric acid and polyvinyl alcohol fibers with an average length of 3-6 mm are dry mixed at a weight ratio of 10:2:1 to obtain composite B; Step c: Mix the composite inorganic activating powder A obtained in step a with the composite B obtained in step b at a weight ratio of 10:1-5:1, and mechanically stir for 10-15 minutes in an environment with humidity less than 30%RH to obtain the composite activator product. Step d: Determine the total amount of admixtures in the low-clinker cementitious materials; the admixtures are at least one of granulated blast furnace slag powder and fly ash; Step e: Calculate the amount of composite activator to be added based on the total amount of blended materials determined in step d; when the total amount of blended materials is 50%-70% of the total weight of cementitious materials, the amount of composite activator to be added is 3%-5% of the total weight of cementitious materials; when the total amount of blended materials is 70%-85% of the total weight of cementitious materials, the amount of composite activator to be added is 5%-8% of the total weight of cementitious materials. Step f: The composite activator product prepared in step c, silicate cement clinker, and the mixed material described in step d are put into a mixer and dry-mixed for 60-90 seconds; Step g: Add mixing water to the dry mixed material from step f and wet mix for 120-180 seconds to obtain a low-clinker cement paste or mortar containing a composite activator.

2. The low-clinker cement activator according to claim 1, characterized in that: The grinding in step a is carried out in a planetary ball mill, with zirconia balls as the grinding media, and the grinding time is 30-45 minutes.

3. The low-clinker cement activator according to claim 1, characterized in that: In step b, the surface of the polyvinyl alcohol fiber is pretreated with a 0.5%-1.0% (w / w) silane coupling agent KH-550 ethanol solution.

4. The low-clinker cement activator according to claim 1, characterized in that: The mechanical stirring in step c is carried out in a mixer equipped with a high-speed shear head, with a stirring speed of 800-1200 rpm.

5. The low-clinker cement activator according to claim 1, characterized in that: The granulated blast furnace slag powder in step d has a specific surface area greater than 420 m² / kg, and the fly ash is Grade I or Grade II fly ash.

6. The low-clinker cement activator according to claim 1, characterized in that: The total weight of the cementitious material in step e is the sum of the weights of the silicate cement clinker, the mixed material, and the finished composite activator.

7. The low-clinker cement activator according to claim 1, characterized in that: The strength grade of the silicate cement clinker in step f is not lower than 52.

5.

8. The low-clinker cement activator according to claim 1, characterized in that: In step g, the mixing water contains redispersible latex powder, which accounts for 0.05%-0.15% of the total weight of the cementitious material.

9. The low-clinker cement activator according to claim 1, characterized in that: The water-cement ratio of the low-clinker cement paste obtained in step g is 0.35-0.

45.

10. The low-clinker cement activator according to claim 1, characterized in that: The low-clinker cement paste with composite activator obtained in step g has an ambient temperature of not less than 5℃.

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