High-performance lightweight self-compacting concrete material and preparation method thereof

Abstract

The invention relates to the technical field of building materials, in particular to a high-performance light self-compacting concrete material and a preparation method thereof. The high-performance light self-compacting concrete material is prepared from the following raw materials in parts by weight: 300 to 400 parts of a cementing material, 150 to 200 parts of water, 90 to 120 parts of coarse aggregate, 600 to 800 parts of fine aggregate, 10 to 20 parts of ettringite, 3 to 6 parts of a water reducing agent, 150 to 200 parts of fly ash and 20 to 30 parts of a fiber reinforcement, p.O42.5 ordinary Portland cement is selected as the gel material, and river sand with the fineness modulus of 2.4-3.0 is selected as the fine aggregate; ceramsite with the particle size of 5-10 mm is selected as the coarse aggregate; according to the prepared fiber reinforcement, the mechanical property and the self-constriction performance of a concrete material are remarkably enhanced, meanwhile, the waterproof anti-permeability performance and the self-compacting performance of the concrete material are effectively improved, the quality of the concrete material is guaranteed, and meanwhile the service life of the concrete material is prolonged to a certain degree.

Description

Technical Field

[0001] This invention relates to the field of building materials technology, specifically to a high-performance lightweight self-compacting concrete material and its preparation method. Background Technology

[0002] In today's era, China has become the world's largest construction nation. However, traditional construction techniques suffer from inefficiency and are no longer sufficient to meet the multiple demands of social production and environmental development. Furthermore, the enormous energy consumption of buildings is a heavy burden, placing a significant strain on my country's economic development and ecological environment. Therefore, in-depth research and active development of new building materials with energy-saving and environmentally friendly characteristics have become an urgent and crucial task.

[0003] Lightweight aggregate concrete, as a newly emerging building material, exhibits many remarkable characteristics. The lightweight aggregate used in it is characterized by low density and high strength, and it also boasts excellent thermal insulation properties. Furthermore, it combines the high compressive strength and good durability of concrete itself, thus bringing together high strength, low density, and a wide range of applications, making it a highly sought-after material.

[0004] Self-compacting concrete (SCC) possesses unique performance characteristics. It achieves flow and compaction under its own weight, completely filling the formwork space even in the presence of densely reinforced steel, resulting in excellent homogeneity. Furthermore, the entire process requires no additional vibration. Preparing self-compacting concrete typically involves careful selection and proper blending of admixtures, binders, and coarse and fine aggregates, along with meticulous mix design. These measures reduce the yield stress of the concrete to a level that can be overcome by the shear stress generated by its own weight, thereby increasing the concrete's fluidity. Simultaneously, it's crucial to ensure the concrete possesses sufficient plastic viscosity to suspend the aggregates in the cement paste, preventing segregation and bleeding, allowing it to flow freely and fully fill the spaces within the formwork, ultimately forming a dense and homogeneous cementitious structure.

[0005] Patent application number CN201910501066.1 discloses a lightweight self-compacting concrete and its preparation method. While the concrete preparation method provided in this patent can solve the problem of construction waste disposal to some extent and alleviate the pressure of resource depletion, it is relatively environmentally friendly. However, the waterproof and impermeable properties and mechanical properties of the concrete material prepared by this patent are relatively insufficient, which affects its quality to some extent. Therefore, this invention provides a high-performance lightweight self-compacting concrete material and its preparation method, aiming to solve the aforementioned technical problems. Summary of the Invention

[0006] The purpose of this invention is to provide a high-performance lightweight self-compacting concrete material and its preparation method. The prepared concrete material not only has excellent mechanical properties and self-shrinkage properties, but also excellent waterproof and seepage-proof properties and self-compacting properties, which ensures the quality of the concrete material and extends its service life to a certain extent.

[0007] To achieve the above objectives, the present invention provides the following technical solution:

[0008] A high-performance lightweight self-compacting concrete material is composed of the following raw materials in parts by weight: 300-400 parts cementitious material, 150-200 parts water, 90-120 parts coarse aggregate, 600-800 parts fine aggregate, 10-20 parts ettringite, 3-6 parts water-reducing agent, 150-200 parts fly ash, and 20-30 parts fiber reinforcement.

[0009] Furthermore, the method for preparing the fiber reinforcement includes the following steps:

[0010] Step 1: Disperse the polypropylene fibers activated by the mixed acid solution uniformly in toluene at a solid-liquid ratio of 2-5 g / L. Then add 0.8-1.5% (by mass) of azobisisobutyronitrile (AIBN) to the polypropylene fibers. After mixing evenly, keep the mixture at 70-80°C for 30-50 min. After the reaction is complete, slowly add 30-50% (by mass) of graphene aqueous dispersion at a concentration of 3-8 g / L to the product. After uniform dispersion, keep the mixture at 70-80°C for 5-8 h. After the reaction is complete, allow the reaction product to cool naturally to room temperature. After filtration, wash the filter cake alternately with toluene and deionized water, and then vacuum dry to constant weight to obtain the modified polypropylene fibers.

[0011] Step 2: Immerse the modified polypropylene fiber in an ethanol solution containing 2-5 wt% coupling agent at 6-10 times its weight. Stir at room temperature for 60-100 min, then filter out the modified polypropylene fiber and heat-treat it at 55-70℃ for 7-10 h. Store the resulting pretreated modified polypropylene fiber for later use.

[0012] Step 3: Add the pretreated modified polypropylene fiber and magnesium acrylate to deionized water, then add N,N-methylenebisacrylamide and potassium persulfate, mix well, and then keep the resulting mixture at 65-75°C for 4-6 hours under nitrogen protection. After the reaction is complete, filter, wash and dry the product components in sequence. The result is the fiber reinforcement.

[0013] The mass ratio of pretreated modified polypropylene fiber, magnesium acrylate, deionized water, N,N-methylenebisacrylamide and potassium persulfate is 12-18:7-10:120-170:0.06-0.1:0.5-0.8.

[0014] Furthermore, the activation method for polypropylene fibers is as follows: The polypropylene fibers are immersed in acetone and soaked at room temperature for 2-3 hours. They are then removed and repeatedly washed with deionized water until the washing liquid is clear. The fibers are then vacuum dried at 60-75°C to a constant weight. The dried polypropylene fibers are then immersed in a mixed acid solution with a mass of 10-20 times their weight at a temperature of 50-60°C for 2-3 hours. The polypropylene fibers are filtered out and washed with deionized water until neutral. Finally, they are vacuum dried to complete the activation of the polypropylene fibers. The mixed acid solution is prepared by mixing concentrated sulfuric acid and concentrated nitric acid in a volume ratio of 3:1.

[0015] Furthermore, the coupling agent is selected from either vinyltrimethoxysilane coupling agent or vinyltriethoxysilane coupling agent.

[0016] Furthermore, the polypropylene fiber has a length of 10–14 mm and a diameter of 16–20 μm.

[0017] Furthermore, the gel material is selected from P.O42.5 ordinary silicate cement.

[0018] Furthermore, the fine aggregate is selected from river sand with a fineness modulus of 2.4 to 3.0; the coarse aggregate is selected from ceramsite with a particle size of 5 to 10 mm.

[0019] Furthermore, the water-reducing agent is selected from any one of BASF polycarboxylate water-reducing agent, lignin sulfonate water-reducing agent, and β-methylnaphthalene sulfonate water-reducing agent.

[0020] Furthermore, the fly ash is Grade I fly ash, with a loss on ignition ≤3.0%, a residue on a 45μm sieve ≤12%, a water requirement ratio ≤95%, and a moisture content ≤1.0%.

[0021] A method for preparing a high-performance lightweight self-compacting concrete material includes the following steps: putting all raw materials except water, water-reducing agent and fiber reinforcement into a mixing device, mixing and stirring evenly, then adding the remaining raw materials, and then mechanically mixing evenly to obtain the high-performance lightweight self-compacting concrete material.

[0022] Compared with the prior art, the beneficial effects of the present invention are:

[0023] This invention uses polypropylene fiber as the starting material. After cleaning with acetone, the fiber is immersed in a mixed acid solution to activate it, thereby introducing reactive groups onto the surface of the polypropylene fiber. The activated polypropylene fiber is dispersed in toluene, and an azobisisobutyronitrile (AIBN) and graphene aqueous dispersion are added. After uniform dispersion, under the action of AIBN, graphene chemically bonds to the activated polypropylene fiber, thus obtaining modified polypropylene fiber composed of graphene and polypropylene fiber.

[0024] Modified polypropylene fibers were immersed in an ethanol solution of a coupling agent. The coupling agent was then "grafted" onto the surface of the modified polypropylene fibers through a chemical reaction. The resulting pretreated modified polypropylene fibers and magnesium acrylate were added to deionized water, followed by the addition of N,N-methylenebisacrylamide and potassium persulfate. After thorough mixing and stirring, the mixture was subjected to a heat-preserving reaction under nitrogen protection. Ultimately, the magnesium acrylate was successfully grafted onto the surface of the modified polypropylene fibers through the "bridging" effect of the coupling agent. The presence of graphene significantly expanded the three-dimensional network structure of the polypropylene fibers, and the magnesium acrylate bonded to the surface of the graphene and polypropylene fibers further expanded the three-dimensional spatial network of the fiber reinforcement. This not only increased the surface roughness but also, given the water-absorbing and swelling properties of magnesium acrylate, which slowly releases moisture in a dry environment, the addition of this water-absorbing resin to concrete effectively counteracted the chemical shrinkage of the concrete material and reduced the probability of autogenous shrinkage. By inhibiting early shrinkage cracking in concrete, the mechanical strength of the concrete material was ensured.

[0025] The fiber-reinforced material prepared by this invention not only significantly enhances the mechanical properties and self-shrinkage properties of concrete materials, but also effectively improves their waterproof and seepage-proof properties and self-compacting properties, ensuring the quality of concrete materials while extending their service life to a certain extent. Detailed Implementation

[0026] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0027] Example 1

[0028] A high-performance lightweight self-compacting concrete material is composed of the following raw materials in parts by weight: 300 parts cementitious material, 150 parts water, 90 parts coarse aggregate, 600 parts fine aggregate, 10 parts ettringite, 3 parts water-reducing agent, 150 parts fly ash and 20 parts fiber reinforcement.

[0029] Among them, P.O42.5 ordinary Portland cement is selected as the gel material; the cementitious material, as a binder, can provide hardness and strength to the concrete material;

[0030] The fine aggregate is river sand with a fineness modulus of 2.4; the coarse aggregate is ceramsite with a particle size of 5mm.

[0031] The fine aggregate, river sand, serves as a filler, filling the voids in the coarse aggregate and making the internal structure of the concrete denser, thereby effectively improving its strength and stability. In terms of improving workability, it enhances the fluidity and cohesiveness of the concrete, which not only facilitates various operations during construction but also prevents segregation during pouring. From the perspective of influencing strength development, river sand can optimize the interface transition zone and participate in the formation of the structure. It works synergistically with the coarse aggregate to help improve the overall strength of the concrete.

[0032] The water-reducing agent selected is BASF RHEOPLUS 420 polycarboxylate water-reducing agent. The water-reducing agent can reduce the water-cement ratio while ensuring the workability of concrete, thereby reducing the slump loss of concrete and maintaining good fluidity at a lower water-cement ratio, thus improving the strength of concrete.

[0033] The fly ash is Class I fly ash, with a loss on ignition ≤3.0%, a residue on a 45μm sieve ≤12%, a water requirement ratio ≤95%, and a moisture content ≤1.0%.

[0034] The specific functions of fly ash are as follows:

[0035] 1. Fly ash can improve the workability of concrete, making it more fluid and reducing bleeding and segregation. This is because the spherical particles of fly ash can act as ball bearings, providing lubrication in the concrete mixture. Furthermore, the addition of fly ash can appropriately extend the setting time of concrete.

[0036] 2. The addition of fly ash in the early stages of concrete hydration slows down the strength gain of the concrete. This is because the pozzolanic activity of fly ash has a relatively small effect in the early stages. However, as time progresses and in the later stages of hydration, the active components in fly ash undergo a secondary hydration reaction with calcium hydroxide, a cement hydration product, to generate CSH gel, thereby increasing the strength of the concrete.

[0037] 3. Fly ash can improve the impermeability of concrete. Its spherical particles and the gel generated by secondary hydration can fill the pores of concrete, preventing the intrusion of moisture and harmful ions. Fly ash can also improve the concrete's resistance to chemical erosion, such as sulfate attack and alkali-aggregate reaction. At the same time, it also helps to improve the freeze-thaw resistance of concrete, reducing the damage caused by freeze-thaw cycles inside the concrete.

[0038] The preparation method of fiber reinforcement includes the following steps:

[0039] Step 1: Disperse the polypropylene fibers activated by the mixed acid solution uniformly in toluene at a solid-liquid ratio of 2 g / L. Then add 0.8% (by mass) of azobisisobutyronitrile (AIBN) to the polypropylene fibers, mix well, and keep the mixture at 70°C for 30 min. After the reaction is complete, slowly add 30% (by mass) of graphene aqueous dispersion at a concentration of 3 g / L to the product components, disperse uniformly, and keep the mixture at 70°C for 5 h. After the reaction is complete, allow the reaction product to cool naturally to room temperature, filter it, and wash the filter cake alternately with toluene and deionized water. Then, vacuum dry it to constant weight to obtain the modified polypropylene fibers.

[0040] Step 2: Immerse the modified polypropylene fiber in an ethanol solution of vinyltrimethoxysilane coupling agent at a concentration of 2 wt% and 6 times its weight. Stir at room temperature for 60 min, then filter out the modified polypropylene fiber and heat-treat it at 55°C for 7 h. Store the resulting pretreated modified polypropylene fiber for later use.

[0041] Step 3: Add the pretreated modified polypropylene fiber and magnesium acrylate to deionized water, then add N,N-methylenebisacrylamide and potassium persulfate, mix well, and then keep the resulting mixture at 65°C for 4 hours under nitrogen protection. After the reaction is complete, filter, wash and dry the product components in sequence. The result is the fiber reinforcement.

[0042] The mass ratio of pretreated modified polypropylene fiber, magnesium acrylate, deionized water, N,N-methylenebisacrylamide and potassium persulfate is 12:7:120:0.06:0.5.

[0043] The activation method of polypropylene fiber is as follows: The polypropylene fiber is immersed in acetone and soaked at room temperature for 2 hours. After soaking, it is taken out and repeatedly washed with deionized water until the washing liquid is clear. Then, it is vacuum dried at 60°C to constant weight. The dried polypropylene fiber is immersed in a mixed acid solution with a mass of 10 times its weight and a temperature of 50°C for 2 hours. The polypropylene fiber is filtered out and washed with deionized water until neutral. Then, it is vacuum dried to complete the activation of the polypropylene fiber. The mixed acid solution is prepared by mixing concentrated sulfuric acid and concentrated nitric acid in a volume ratio of 3:1. The polypropylene fiber has a length of 10 mm and a diameter of 16 μm.

[0044] A method for preparing a high-performance lightweight self-compacting concrete material includes the following steps: putting all raw materials except water, water-reducing agent and fiber reinforcement into a mixing device, mixing and stirring evenly, then adding the remaining raw materials, and then mechanically mixing evenly to obtain the high-performance lightweight self-compacting concrete material.

[0045] Example 2

[0046] The preparation method of the high-performance lightweight self-compacting concrete material provided in this embodiment is basically the same as that in Embodiment 1, except that the specific composition of the concrete material and the preparation method of the fiber reinforcement are not exactly the same. The specific composition of the concrete material and the preparation method of the fiber reinforcement in this embodiment are as follows:

[0047] A high-performance lightweight self-compacting concrete material is composed of the following raw materials in parts by weight: 350 parts cementitious material, 180 parts water, 100 parts coarse aggregate, 700 parts fine aggregate, 15 parts ettringite, 5 parts water-reducing agent, 160 parts fly ash and 25 parts fiber reinforcement.

[0048] The preparation method of fiber reinforcement includes the following steps:

[0049] Step 1: Disperse the polypropylene fibers activated by the mixed acid solution uniformly in toluene at a solid-liquid ratio of 3 g / L. Then add 1.2% (by mass) of azobisisobutyronitrile (AIBN) of the polypropylene fibers, mix well, and keep the mixture at 75°C for 40 min. After the reaction is complete, slowly add 40% (by mass) of graphene aqueous dispersion at a concentration of 5 g / L to the product components, disperse uniformly, and keep the mixture at 75°C for 6 h. After the reaction is complete, allow the reaction product to cool naturally to room temperature, filter it, and wash the filter cake alternately with toluene and deionized water. Then, vacuum dry it to constant weight to obtain the modified polypropylene fibers.

[0050] Step 2: Immerse the modified polypropylene fiber in an ethanol solution containing 8 times its weight and 4 wt% coupling agent. Stir at room temperature for 80 min, then filter out the modified polypropylene fiber and heat-treat it at 65°C for 8 h. Store the resulting pretreated modified polypropylene fiber for later use.

[0051] Step 3: Add the pretreated modified polypropylene fiber and magnesium acrylate to deionized water, then add N,N-methylenebisacrylamide and potassium persulfate, mix well, and then keep the resulting mixture at 70°C for 5 hours under nitrogen protection. After the reaction is complete, filter, wash and dry the product components in sequence. The result is the fiber reinforcement.

[0052] The mass ratio of pretreated modified polypropylene fiber, magnesium acrylate, deionized water, N,N-methylenebisacrylamide and potassium persulfate is 15:8:150:0.08:0.6.

[0053] The activation method of polypropylene fiber is as follows: immerse the polypropylene fiber in acetone, soak it at room temperature for 3 hours, then remove it and wash it repeatedly with deionized water until the washing liquid is clear. Then, vacuum dry it at 70°C to constant weight. After drying, immerse the polypropylene fiber in a mixed acid solution with a mass of 15 times its weight and a temperature of 55°C for 2 hours. Filter out the polypropylene fiber and wash it with deionized water until neutral. Then, vacuum dry it to complete the activation of the polypropylene fiber. The mixed acid solution is prepared by mixing concentrated sulfuric acid and concentrated nitric acid in a volume ratio of 3:1.

[0054] Example 3

[0055] The preparation method of the high-performance lightweight self-compacting concrete material provided in this embodiment is basically the same as that in Embodiment 1, except that the specific composition of the concrete material and the preparation method of the fiber reinforcement are not exactly the same. The specific composition of the concrete material and the preparation method of the fiber reinforcement in this embodiment are as follows:

[0056] A high-performance lightweight self-compacting concrete material is composed of the following raw materials in parts by weight: 400 parts cementitious material, 200 parts water, 120 parts coarse aggregate, 800 parts fine aggregate, 20 parts ettringite, 6 parts water-reducing agent, 200 parts fly ash and 30 parts fiber reinforcement.

[0057] The preparation method of fiber reinforcement includes the following steps:

[0058] Step 1: Disperse the polypropylene fibers activated by the mixed acid solution uniformly in toluene at a solid-liquid ratio of 5 g / L. Then add 1.5% (by mass) of azobisisobutyronitrile (AIBN) of the polypropylene fibers, mix well, and keep the mixture at 80°C for 50 min. After the reaction is complete, slowly add 50% (by mass) of graphene aqueous dispersion at a concentration of 8 g / L to the product components, disperse uniformly, and keep the mixture at 80°C for 8 h. After the reaction is complete, allow the reaction product to cool naturally to room temperature, filter it, and wash the filter cake alternately with toluene and deionized water. Then, vacuum dry it to constant weight to obtain the modified polypropylene fibers.

[0059] Step 2: Immerse the modified polypropylene fiber in an ethanol solution containing 10 times its weight and 5 wt% coupling agent. Stir at room temperature for 100 min, then filter out the modified polypropylene fiber and heat-treat it at 70°C for 10 h. Store the resulting pretreated modified polypropylene fiber for later use.

[0060] Step 3: Add the pretreated modified polypropylene fiber and magnesium acrylate to deionized water, then add N,N-methylenebisacrylamide and potassium persulfate, mix well, and then keep the resulting mixture at 75°C for 6 hours under nitrogen protection. After the reaction is complete, filter, wash and dry the product components in sequence. The result is the fiber reinforcement.

[0061] The mass ratio of pretreated modified polypropylene fiber, magnesium acrylate, deionized water, N,N-methylenebisacrylamide and potassium persulfate is 18:10:170:0.1:0.8.

[0062] The activation method of polypropylene fiber is as follows: immerse the polypropylene fiber in acetone, soak it at room temperature for 3 hours, then remove it and wash it repeatedly with deionized water until the washing liquid is clear. Then, vacuum dry it at 75°C to constant weight. After drying, immerse the polypropylene fiber in a mixed acid solution with a mass of 20 times its weight and a temperature of 60°C for 3 hours. Filter out the polypropylene fiber and wash it with deionized water until neutral. Then, vacuum dry it to complete the activation of the polypropylene fiber. The mixed acid solution is prepared by mixing concentrated sulfuric acid and concentrated nitric acid in a volume ratio of 3:1.

[0063] The difference between Comparative Example 1 and Example 1 is that an equal amount of modified polypropylene fiber is used to replace the fiber reinforcement in this comparative example.

[0064] Comparative Example 2 differs from Example 1 in that an equal amount of polypropylene fiber is used instead of fiber reinforcement in this comparative example.

[0065] Performance testing: The concrete material samples prepared in Examples 1-3 and Comparative Examples 1-2 were molded into cubic workpieces with dimensions of 150mm × 150mm × 150mm in a mold. The relevant properties of each group of cubic workpieces or concrete material samples were then tested, and the test results are recorded in the table below:

[0066]

[0067] By comparing and analyzing the relevant data in the table, it can be seen that the concrete material prepared by this invention not only possesses excellent mechanical properties and self-shrinkage properties, but also excellent waterproof and seepage-resistant properties and self-compacting properties. This ensures the quality of the concrete material while extending its service life to a certain extent. Therefore, this invention provides a high-performance lightweight self-compacting concrete material and its preparation method, which have broader market prospects and are more suitable for widespread application.

[0068] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0069] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A high-performance lightweight self-compacting concrete material, characterized in that, It is composed of the following raw materials in parts by weight: 300-400 parts cementitious material, 150-200 parts water, 90-120 parts coarse aggregate, 600-800 parts fine aggregate, 10-20 parts ettringite, 3-6 parts water-reducing agent, 150-200 parts fly ash and 20-30 parts fiber reinforcement.

2. The high-performance lightweight self-compacting concrete material according to claim 1, characterized in that, The method for preparing the fiber reinforcement includes the following steps: Step 1: Disperse the polypropylene fibers activated by the mixed acid solution uniformly in toluene at a solid-liquid ratio of 2-5 g / L. Then add 0.8-1.5% (by mass) of azobisisobutyronitrile (AIBN) to the polypropylene fibers. After mixing evenly, keep the mixture at 70-80°C for 30-50 min. After the reaction is complete, slowly add 30-50% (by mass) of graphene aqueous dispersion at a concentration of 3-8 g / L to the product. After uniform dispersion, keep the mixture at 70-80°C for 5-8 h. After the reaction is complete, allow the reaction product to cool naturally to room temperature. After filtration, wash the filter cake alternately with toluene and deionized water, and then vacuum dry to constant weight to obtain the modified polypropylene fibers. Step 2: Immerse the modified polypropylene fiber in an ethanol solution containing 2-5 wt% coupling agent at 6-10 times its weight. Stir at room temperature for 60-100 min, then filter out the modified polypropylene fiber and heat-treat it at 55-70℃ for 7-10 h. Store the resulting pretreated modified polypropylene fiber for later use. Step 3: Add the pretreated modified polypropylene fiber and magnesium acrylate to deionized water, then add N,N-methylenebisacrylamide and potassium persulfate, mix well, and then keep the resulting mixture at 65-75°C for 4-6 hours under nitrogen protection. After the reaction is complete, filter, wash and dry the product components in sequence. The result is the fiber reinforcement. The mass ratio of pretreated modified polypropylene fiber, magnesium acrylate, deionized water, N,N-methylenebisacrylamide and potassium persulfate is 12-18:7-10:120-170:0.06-0.1:0.5-0.

8.

3. The high-performance lightweight self-compacting concrete material according to claim 2, characterized in that, The activation method for polypropylene fibers is as follows: The polypropylene fibers are immersed in acetone and soaked at room temperature for 2-3 hours. They are then removed and repeatedly washed with deionized water until the washing liquid is clear. The fibers are then vacuum dried at 60-75°C to constant weight. The dried polypropylene fibers are then immersed in a mixed acid solution with a mass of 10-20 times their weight and a temperature of 50-60°C for 2-3 hours. The polypropylene fibers are filtered out and washed with deionized water until neutral. Finally, they are vacuum dried to complete the activation of the polypropylene fibers. The mixed acid solution is prepared by mixing concentrated sulfuric acid and concentrated nitric acid in a volume ratio of 3:

1.

4. The high-performance lightweight self-compacting concrete material according to claim 2, characterized in that: The coupling agent is selected from either vinyltrimethoxysilane coupling agent or vinyltriethoxysilane coupling agent.

5. A high-performance lightweight self-compacting concrete material according to claim 2 or 3, characterized in that: The polypropylene fibers have a length of 10–14 mm and a diameter of 16–20 μm.

6. The high-performance lightweight self-compacting concrete material according to claim 1, characterized in that: The gel material is P.O42.5 ordinary silicate cement.

7. The high-performance lightweight self-compacting concrete material according to claim 1, characterized in that: The fine aggregate is river sand with a fineness modulus of 2.4 to 3.0; the coarse aggregate is ceramsite with a particle size of 5 to 10 mm.

8. The high-performance lightweight self-compacting concrete material according to claim 1, characterized in that: The water-reducing agent is selected from any one of BASF polycarboxylate water-reducing agent, lignin sulfonate water-reducing agent, and β-methylnaphthalene sulfonate water-reducing agent.

9. The high-performance lightweight self-compacting concrete material according to claim 1, characterized in that: The fly ash is Grade I fly ash, with a loss on ignition ≤3.0%, a residue on a 45μm sieve ≤12%, a water requirement ratio ≤95%, and a moisture content ≤1.0%.

10. A method for preparing a high-performance lightweight self-compacting concrete material according to any one of claims 1 to 9, characterized in that, The process includes the following steps: adding all raw materials except water, water-reducing agent and fiber reinforcement into a mixing equipment, mixing and stirring evenly, then adding the remaining raw materials, and then mechanically mixing evenly to obtain high-performance lightweight self-compacting concrete material.

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