Concrete material for reservoir edge protection waterproof layer and preparation method of concrete material

Abstract

The invention relates to the technical field of building materials, in particular to a concrete material for a reservoir edge protection waterproof layer and a preparation method of the concrete material. The invention discloses a concrete material for a reservoir edge protection waterproof layer. The concrete material is prepared from the following preparation raw materials: 180 to 200 parts of cement, 850 to 900 parts of fine aggregate, 920 to 960 parts of coarse aggregate, 78 to 85 parts of fly ash, 60 to 65 parts of mineral powder, 12 to 15 parts of hydrophobic modified polypropylene fiber, 12 to 15 parts of organic silicon modified acrylic emulsion, 3 to 5 parts of high-efficiency water reducing agent and 200 to 220 parts of water. Through solid waste resource utilization, functional material molecular design and a multi-component synergistic enhancement mechanism, the problems that traditional reservoir slope protection concrete is low in strength, prone to leakage, poor in crack resistance, insufficient in durability and the like are successfully solved, meanwhile, the engineering goals of low cost, high environmental protection and easy construction are achieved, and the concrete is suitable for high-humidity, hydraulic scouring and other severe environments and has wide application prospects. And an innovative solution is provided for water conservancy project protection materials.

Description

Technical Field

[0001] The present application relates to the technical field of building materials, and in particular to a concrete material for a reservoir side protection waterproof layer and a preparation method thereof. Background Art

[0002] At present, in order to meet the performance requirements of anti-seepage and anti-cracking, cement concrete mainly uses inorganic waterproof materials, expansion agents, shrinkage reducers, fibers, mineral admixtures, etc. as additives. In general, those skilled in the art usually consider adding only one of the aforementioned additives, but often cannot take into account all the properties of concrete, especially it is difficult to take into account mechanical strength, bonding strength, anti-seepage performance and anti-cracking performance, which makes the resulting concrete difficult to apply in projects with higher use requirements, such as dams or reservoirs. Chinese patent CN 114790097 B provides an anti-seepage concrete for reservoir dams and a preparation method thereof, which combines the advantages of magnetic graphene, fiber and mineral admixtures to obtain a mixed additive, and obtains a concrete with relatively balanced mechanical strength and anti-seepage performance. However, the patent does not examine the anti-cracking performance of the resulting concrete, and the mechanical strength of the resulting concrete is insufficient, inferior to the common concrete in the prior art, and has low practical application value.

[0003] Therefore, developing a concrete with high mechanical strength and bonding strength as well as good impermeability and crack resistance has become a challenging research task. Summary of the Invention

[0004] The purpose of this application is to address the deficiencies of current technology and provide a concrete material for a reservoir edge protection waterproof layer and a preparation method thereof. The concrete material for a reservoir edge protection waterproof layer prepared in this application has the advantages of simple production, low cost, long service life, and excellent mechanical strength, bonding strength, impermeability and crack resistance.

[0005] In the first aspect, the present application provides a concrete material for a reservoir edge protection waterproof layer, which adopts the following technical solution: A concrete material for a reservoir side protection waterproof layer comprises the following raw materials, calculated by mass: 180-200 parts of cement, 850-900 parts of fine aggregate, 920-960 parts of coarse aggregate, 78-85 parts of fly ash, 60-65 parts of mineral powder, 12-15 parts of hydrophobically modified polypropylene fiber, 12-15 parts of organosilicon-modified acrylic emulsion, 3-5 parts of high-efficiency water reducer, and 200-220 parts of water, wherein the mineral powder is modified manganese slag powder.

[0006] Through the above technical solution, cement acts as a binder, providing early strength and adhesion, forming the cement paste matrix. It chemically bonds with the epoxy groups of the silicone-modified acrylic emulsion, enhancing interfacial bonding strength. Fine aggregate (sand) fills the gaps between coarse aggregate, optimizing gradation and reducing porosity; coarse aggregate (stone) forms the concrete skeleton, bearing the primary mechanical load. Aggregate gradation, combined with a high-efficiency water reducer, achieves a high-density structure and improves impermeability. Fly ash, through its pozzolanic effect, fills micropores, enhancing later-stage strength and reducing hydration heat, mitigating the risk of thermal cracking. Together with mineral powder, it optimizes particle gradation to form a dense microstructure. Modified manganese slag powder, such as electrolytic manganese slag, is treated with potassium hydroxide and hydrogen peroxide to remove harmful impurities. High-temperature sintering generates active aluminosilicates, enhancing the pozzolanic effect. Mullite provides high-temperature stability and improves compressive and flexural strength. Combined with hydrophobic fibers, it forms a multi-scale reinforcement system, inhibiting crack propagation. Hydrophobically modified polypropylene fibers and aminosilane coupling agents enhance fiber-matrix interfacial bonding; trifluoroacetic anhydride introduces -CF3 to impart superhydrophobicity, with a three-dimensional random distribution inhibiting plastic shrinkage cracks; and hydrophobic properties block capillary water seepage channels. Together with the silicone emulsion, a hydrophobic double network is formed, synergistically improving impermeability. The epoxy groups in the silicone-modified acrylic emulsion react with the Ca in the cement. 2+ Bonding strengthens the interface transition zone, filling micropores to reduce permeability; the silicone segments form a hydrophobic film on the surface, inhibiting surface crack propagation and improving dynamic crack resistance. Together with the hydrophobic fibers, they form a hydrophobic-mechanical double barrier to block external water erosion. High-efficiency water reducers reduce the water-binder ratio and increase density; improve workability and ensure uniform dispersion of fibers / aggregates. The low water-binder ratio combined with the micro-filling effect of fly ash / mineral powder achieves nanoscale pore structure optimization. Water precisely controls the water-binder ratio to balance workability and strength; combined with a water reducer, a low-viscosity, high-fluidity slurry is achieved. In short, this system achieves comprehensive optimization of mechanical properties, bonding strength, impermeability, and crack resistance through multi-component functional design and synergistic effects.

[0007] Preferably, the method for preparing the modified manganese slag powder comprises the following steps: S21. Mix 100 parts of electrolytic manganese slag, 40-45 parts of mullite, and 60-65 parts of fly ash in parts by mass to obtain a mixture A; S22. Mix 100 parts of mixture A, 8-9 parts of 25% potassium hydroxide solution, 8-9 parts of 25% hydrogen peroxide solution, and 200 parts of deionized water, in parts by mass; heat to 65° C. for 6-7 hours, then naturally cool, filter, and dry to obtain mixture B. S23. Place the mixture B in a muffle furnace, sinter at 950-980° C. for 120-150 minutes, cool naturally, grind into powder, and sieve to obtain modified manganese slag powder with an average particle size of 6-9 μm.

[0008] By adopting the above technical solution, step S21: raw material mixing, electrolytic manganese slag: contains silicon aluminum oxides and residual sulfates, which need to be modified to eliminate impurities; mullite (3Al2O3·2SiO2): high temperature stability mineral, enhances the crystallinity of the sintered material; fly ash: supplements active silicon aluminum components, optimizes the volcanic ash activity of the sintering reaction; dry mixing until homogeneous to ensure sufficient subsequent reaction. Step S22: chemical activation treatment, KOH: dissolves free sulfates (such as CaSO4) in manganese slag to reduce the risk of later concrete expansion; H2O2: oxidizes and decomposes organic impurities and low-valent sulfides (such as S 2- →SO4 2- ); High temperature stirring: promotes the pre-activation of aluminosilicate to form an amorphous precursor. Filter to remove soluble salts (such as K2SO4) and dry to avoid agglomeration. Step S23: High temperature sintering and grinding, mullite: acts as a crystal nucleus to induce the recrystallization of aluminosilicate to form a high temperature resistant skeleton; fly ash and manganese slag: generate highly active minerals such as β-C2S (belite) and calcium aluminum feldspar (Ca2Al2SiO7) through solid phase reaction. Grinding: crush the sintered block to an average particle size of 6-9 microns to increase the specific surface area; sieving: control the particle size distribution to avoid agglomeration and affect dispersibility. The role and synergistic mechanism of the prepared modified manganese slag powder in concrete: 1) Core function, mechanical strength improvement: the active aluminosilicate (such as CSH gel precursor) generated by high temperature sintering reacts with cement hydration products to fill pores and strengthen the interface transition zone (ITZ), thereby improving compressive strength; mullite crystals act as a rigid reinforcement phase to improve flexural strength. Durability optimization: Chemical treatment removes sulfates to prevent later expansion and cracking; highly reactive minerals accelerate volcanic ash reactions, reduce Ca(OH)2 content, and minimize the risk of dissolution. 2) Synergy with hydrophobically modified polypropylene fibers: Multi-scale reinforcement: Manganese slag powder strengthens the matrix, while fibers bridge microcracks, forming a "rigid-flexible composite" system; Anti-permeability synergy: Manganese slag powder fills capillary pores, while fibers block macroscopic water seepage channels. Synergy with silicone-modified acrylic emulsion: Interface reinforcement: The high specific surface area of ​​manganese slag powder adsorbs epoxy groups in the emulsion, forming a "mineral-polymer" interpenetrating network; Hydrophobic complementarity: Manganese slag powder optimizes matrix density, while the emulsion covers surface micropores, achieving gradient waterproofing. In summary, through the above preparation process, modified manganese slag powder not only achieves high-value utilization of industrial solid waste, but also, through multi-component collaborative design, enables the comprehensive performance of concrete to meet the stringent requirements of reservoir slope protection projects for high strength, high durability, impermeability, and crack resistance.

[0009] Preferably, the preparation method of the hydrophobically modified polypropylene fiber comprises the following steps: S31, adding 10 parts by mass of polypropylene fiber to 50 parts by mass of 75% ethanol aqueous solution, adjusting the pH to 4-5, adding 0.8 parts of aminosilane coupling agent, stirring and reacting for 3-4 hours, filtering, washing with water, and drying to obtain silane-modified polypropylene fiber; S32. According to the mass fractions, 20 parts of 3% trifluoroacetic anhydride dimethylformamide solution are heated to 90°C, 10 parts of silane-modified polypropylene fiber are added, and the pH value of the dispersion is adjusted to 9-10 with a 10% sodium hydroxide aqueous solution. The mixture is reacted at a constant temperature for 5-6 hours, filtered, washed with water, and dried to obtain hydrophobically modified polypropylene fiber.

[0010] By adopting the above technical solution, step S31: surface modification of aminosilane coupling agent, silane hydrolysis: in an acidic environment, the methoxy group (-OCH3) of the aminosilane coupling agent is hydrolyzed to form silanol (-Si-OH). Silanol is adsorbed on the surface of the polypropylene fiber through hydrogen bonds, and forms a covalent bond (Si-OC) after dehydration condensation, introducing an amino group (-NH2) active site. Step S32: hydrophobic modification with trifluoroacetic anhydride. Under alkaline conditions, trifluoroacetic anhydride ((CF3CO)2O) reacts with the amino group (-NH2) on the fiber surface to undergo a nucleophilic substitution reaction to form an amide bond and introduce a trifluoromethyl group (-CF3). The -CF3 group has low surface energy, giving the fiber superhydrophobicity. The role of the prepared hydrophobically modified polypropylene fiber in concrete: Mechanical enhancement: The fiber forms a spatial network structure in the concrete, inhibiting the propagation of microcracks through bridging action, and improving flexural strength and toughness; Interface strengthening: The aminosilane coupling agent enhances the fiber-matrix interface adhesion and reduces fiber slippage. Improved impermeability: Blocking of hydrophobic channels: -CF3 groups make the fiber surface super-hydrophobic, blocking the capillary water absorption path; Self-sealing of micro-cracks: After the fiber is debonded from the matrix, the hydrophobic surface repels water from invading the cracks. Optimized crack resistance: Plastic stage crack suppression: The fiber inhibits early plastic shrinkage cracks; Dynamic load buffering: The fiber elastic modulus matches the concrete, delaying crack propagation under impact loads. In short, through the above-mentioned modification process, hydrophobic polypropylene fiber not only solves the problems of poor compatibility and easy corrosion between traditional fibers and cement matrices, but also, through functional design and multi-component synergy, enables the comprehensive performance of concrete to meet the stringent requirements of reservoir slope protection projects for high strength, high durability, impermeability and crack resistance.

[0011] Preferably, the aminosilane coupling agent is one of 3-aminopropyltrihydroxysilane coupling agent and γ-aminopropyltrimethoxysilane.

[0012] Preferably, the preparation method of the organosilicon-modified acrylic emulsion comprises the following steps: S51. Under a nitrogen atmosphere, add bisdimethylsilylamine and ethanol to a reaction flask according to their mass fractions, stir evenly, then add perfluorooctyl chloride and sodium hydride, stir, raise the temperature to 86-90° C., react for 12-14 hours, distill under reduced pressure, and purify by column chromatography to obtain an alkenyl organosilicone fluorine monomer; S52. In a nitrogen atmosphere, add isopropyl alcohol, acrylic acid, butyl methacrylate, epoxy resin E-44 and alkenyl organosilicon fluorine monomer into the reaction flask according to their mass parts. After they are completely dissolved, add azobisisobutyronitrile, raise the temperature to 85-90°C and react for 4-5 hours, cool to 40-43°C, add triethylamine to neutralize, and add deionized water to disperse under high-speed stirring to obtain an organosilicon-modified acrylic emulsion.

[0013] By adopting the above technical solution, Step S51: Preparation of alkenyl organosilicon fluoromonomers, Silylamine Activation: In ethanol, bisdimethylsilylamine reacts with NaH to generate a strongly nucleophilic silylamine anion. Fluoroalkylation: The silylamine anion attacks the Cl atom of perfluorooctyl chloride, undergoing nucleophilic substitution to generate a fluorinated siloxane monomer. Purification: Low-boiling point byproducts are removed by vacuum distillation, and the target product is separated by column chromatography. The alkenyl organosilicon fluoromonomer contains a fluorinated carbon chain (-C8F17) and a polymerizable alkenyl group (e.g., CH2=CH-), which imparts hydrophobicity and reactivity to the final emulsion. Step S52: Emulsion Copolymerization: Free Radical Copolymerization: Azobisisobutyronitrile undergoes thermal decomposition to generate free radicals, which initiate copolymerization of acrylic acid, butyl methacrylate, epoxy resin E-44, and the organosilicon fluoromonomer to form an epoxy-fluorosilicone-modified acrylic copolymer. Epoxy Group Retention: The reaction temperature is controlled (85-90°C) to prevent epoxy ring opening and ensure bonding with cement hydration products. Emulsion stabilization: triethylamine neutralizes the carboxylic acid groups (-COOH→-COO - ) to form water-dispersible salts, and high-speed shearing to achieve nano-scale latex particles. Nitrogen protection: prevent oxygen from inhibiting free radical polymerization; temperature gradient: after high-temperature polymerization, cool to 40°C for neutralization to avoid emulsion demulsification. The role of the prepared silicone-modified acrylic emulsion in concrete: Mechanical properties enhancement: The epoxy groups (-O-CH2-CH(O)-CH2-) in the emulsion react with the cement hydration product Ca 2+Forming coordination bonds strengthens the interfacial transition zone (ITZ) and enhances bond strength. Flexible segment toughening: Acrylate segments (Tg ≈ -20°C) impart flexibility to concrete, improving flexural strength. Optimizing impermeability: Micropore filling: Nano-latex particles fill the pores of cement paste, reducing porosity. Hydrophobic film formation: Fluorosilicon segments (-Si-O-C8F17) self-assemble into a hydrophobic film on the concrete surface, blocking water penetration. Improving crack resistance: The ductility of the emulsion polymer film inhibits microcrack propagation. Flexible segments absorb dynamic load energy, reducing macrocracking caused by stress concentration. Synergy with hydrophobically modified polypropylene fibers: The fiber's internal hydrophobic network (-CF3) + the emulsion's surface hydrophobic film (-C8F17) form a three-level waterproof barrier: "bulk-interface-surface." Mechanical complementarity: The fiber bears tensile loads, while the emulsion transmits shear stress, synergistically enhancing impact resistance. Synergy with modified manganese slag powder: The high surface area of ​​manganese slag powder absorbs epoxy groups in the emulsion, forming a mineral-polymer interpenetrating network and reducing ITZ porosity. The carboxylic acid groups (-COOH) in the emulsion promote the pozzolanic reaction of the manganese slag powder, accelerating the formation of CSH gel. In short, this emulsion integrates hydrophobicity, adhesion, and flexibility through molecular design. Combined with the synergistic effects of multiple components, it comprehensively improves the overall performance of concrete.

[0014] Preferably, in step S51, the mass ratio of bisdimethylsilylamine, ethanol, perfluorooctyl chloride and sodium hydride is 1:(35-38):(2.8-3):(0.22-0.28).

[0015] Preferably, in step S52, the mass ratio of the isopropyl alcohol, acrylic acid, butyl methacrylate, epoxy resin E-44, alkenyl organosilicone fluorine monomer, azobisisobutyronitrile, triethylamine and deionized water is 100:13:37:(9-11):(8-10):(0.8-1.2):(2.5-3):85.

[0016] Preferably, the fine aggregate is quartz sand with a particle size of 0.5-0.9 mm; the coarse aggregate is gravel with a continuous gradation of 5-25 mm.

[0017] Preferably, the cement is ordinary Portland cement of grade P·O42.5; the high-efficiency water reducer is ZWL-A-IX water reducer produced by Zhejiang Wulong Chemical Industry Co., Ltd.; and the fly ash is grade II ash.

[0018] In a second aspect, the present application provides a method for preparing a concrete material for a reservoir edge protection waterproof layer, which adopts the following technical solution: As a general technical concept, the present application also provides a method for preparing the above-mentioned concrete material for the reservoir edge protection waterproof layer, comprising the following steps: According to the mass proportions, cement, coarse aggregate, fine aggregate, hydrophobically modified polypropylene fiber, fly ash and mineral powder are first poured into a concrete mixer and dry-mixed for 1.5-2 minutes. After mixing evenly, water is added and mixed for 1-2 minutes. Then, a high-efficiency water reducer and silicone-modified acrylic emulsion are added and stirred for 2-3 minutes to obtain the concrete material for the reservoir side protection waterproof layer.

[0019] In summary, the beneficial technical effects of this application are: 1. Comprehensive mechanical properties are significantly improved Compressive strength: The highly active aluminosilicate in the modified manganese slag powder works synergistically with the cement hydration products, combined with the bridging reinforcement effect of the hydrophobic fiber, to achieve a 28-day compressive strength of ≥81 MPa.

[0020] Flexural strength: The three-dimensional distribution of fibers and the flexible toughening effect of silicone emulsion work together to achieve a flexural strength of 16-17 MPa.

[0021] Bonding strength: The epoxy group of the silicone emulsion chemically bonds with the cement interface, and the bonding strength between new and old concrete reaches above 2.0MPa (JGJ / T 70-2009 standard requirements).

[0022] 2. Anti-seepage and waterproof performance breakthrough anti-seepage level: P11 or above (GB / T 50082-2009 standard), hydrophobic fiber network blocks capillary channels + latex hydrophobic film covers the surface, significantly improving anti-seepage performance.

[0023] 3. Crack resistance and durability optimization: Micro-filling effect of fly ash and manganese slag powder + fiber-constrained plastic shrinkage, the number of cracks ≤ 3 / m 2 . DETAILED DESCRIPTION

[0024] The embodiments of the present application will be described in detail below with reference to the examples, but those skilled in the art will appreciate that the following examples are merely illustrative of the present application and should not be construed as limiting the scope of the present application. Where specific conditions are not specified in the examples, the conditions were followed according to conventional conditions or manufacturer recommendations. Where the manufacturer of the reagents or instruments used is not specified, they are all commercially available conventional products. The high-efficiency water reducer was purchased from the ZWL-A-IX water reducer produced by Zhejiang Wulong Chemical Co., Ltd.

[0025] In the following examples and preparation examples, 1 part means 100 g.

[0026] Preparation Example 1 Preparation of modified manganese slag powder The preparation method of modified manganese slag powder comprises the following steps: S21. Mix 100 parts of electrolytic manganese slag, 43 parts of mullite, and 62 parts of fly ash in parts by mass to obtain a mixture A. S22. Mix 100 parts of mixture A, 9 parts of 25% potassium hydroxide solution, 8 parts of 25% hydrogen peroxide solution, and 200 parts of deionized water in parts by mass; heat to 65° C. for 6.7 hours, then cool naturally, filter, and dry to obtain mixture B; S23. Place the mixture B in a muffle furnace and sinter it at 970° C. for 140 minutes. After natural cooling, grind it into powder and sieve it to obtain modified manganese slag powder with an average particle size of 7 μm.

[0027] Preparation of Comparative Example 1: Preparation of Modified Manganese Slag Powder The preparation method of modified manganese slag powder comprises the following steps: S21. Mix 100 parts of electrolytic manganese slag and 62 parts of fly ash in parts by mass to obtain a mixture A; S22. Mix 100 parts of mixture A, 9 parts of 25% potassium hydroxide solution, 8 parts of 25% hydrogen peroxide solution, and 200 parts of deionized water in parts by mass; heat to 65° C. for 6.7 hours, then cool naturally, filter, and dry to obtain mixture B; S23. Place the mixture B in a muffle furnace and sinter it at 970° C. for 140 minutes. After natural cooling, grind it into powder and sieve it to obtain modified manganese slag powder with an average particle size of 7 μm.

[0028] Preparation Example 2 Hydrophobically modified polypropylene fiber The preparation method of hydrophobically modified polypropylene fiber comprises the following steps: S31. Add 10 parts by mass of polypropylene fibers (0.5 mm in diameter and 12 mm in length) to 50 parts by mass of a 75% aqueous ethanol solution, adjust the pH to 4.5, add 0.8 parts of γ-aminopropyltrimethoxysilane, and stir to react for 3.6 hours. Filter, wash with water, and dry to obtain silane-modified polypropylene fibers. S32. According to the mass fractions, 20 parts of 3% trifluoroacetic anhydride dimethylformamide solution were heated to 90°C, 10 parts of silane-modified polypropylene fibers were added, and the pH of the dispersion was adjusted to 9.3 with a 10% sodium hydroxide aqueous solution. The mixture was reacted at a constant temperature for 5.6 hours, filtered, washed with water, and dried to obtain hydrophobically modified polypropylene fibers.

[0029] Preparation Example 3 Preparation of silicone-modified acrylic emulsion The preparation method of the organosilicon-modified acrylic emulsion comprises the following steps: S51. Under a nitrogen atmosphere, add 1 part of bisdimethylsilylamine and 36 parts of ethanol to a reaction flask according to their weight parts, stir evenly, then add 2.9 parts of perfluorooctyl chloride and 0.25 parts of sodium hydride, stir, raise the temperature to 87°C, react for 13 hours, distill under reduced pressure, and purify by column chromatography to obtain an alkenyl organosilicone fluorine monomer; S52. According to the mass parts, under a nitrogen atmosphere, add 100 parts of isopropanol, 13 parts of acrylic acid, 37 parts of butyl methacrylate, 10 parts of epoxy resin E-44 and 9 parts of alkenyl organosilicon fluorine monomer into the reaction flask. After they are completely dissolved, add 1 part of azobisisobutyronitrile, raise the temperature to 87°C and react for 4.5 hours, cool to 42°C, add 2.8 parts of triethylamine to neutralize, and add 85 parts of deionized water to disperse under high-speed stirring to obtain an organosilicon-modified acrylic emulsion.

[0030] Example 1 A concrete material for a reservoir edge protection waterproof layer comprises the following raw materials, measured by mass: 180 parts of cement, 850 parts of fine aggregate, 920 parts of coarse aggregate, 78 parts of fly ash, 60 parts of mineral powder, 12 parts of hydrophobically modified polypropylene fiber, 12 parts of organosilicon-modified acrylic emulsion, 3 parts of high-efficiency water reducer, and 200 parts of water, wherein the mineral powder is the modified manganese slag powder prepared in Preparation Example 1, the fine aggregate is quartz sand with a particle size of 0.5-0.9 mm; the coarse aggregate is gravel with a continuous gradation of 5-25 mm; the cement is ordinary Portland cement of P·O42.5 grade; and the fly ash is Grade II ash. The method for preparing the concrete material for the reservoir edge protection waterproof layer comprises the following steps: According to the mass proportions, cement, coarse aggregate, fine aggregate, hydrophobically modified polypropylene fiber, fly ash and mineral powder were first poured into a concrete mixer and dry-mixed for 1.5 minutes. After mixing evenly, water was added and mixed for 1 minute. Then, a high-efficiency water reducer and silicone-modified acrylic emulsion were added and stirred for 2 minutes to obtain the concrete material for the reservoir side protection waterproof layer.

[0031] Example 2 A concrete material for a reservoir edge protection waterproof layer comprises the following raw materials, measured by mass: 200 parts of cement, 900 parts of fine aggregate, 960 parts of coarse aggregate, 85 parts of fly ash, 65 parts of mineral powder, 15 parts of hydrophobically modified polypropylene fiber, 15 parts of organosilicon-modified acrylic emulsion, 5 parts of high-efficiency water reducer, and 220 parts of water, wherein the mineral powder is the modified manganese slag powder prepared in Preparation Example 1, the fine aggregate is quartz sand with a particle size of 0.5-0.9 mm; the coarse aggregate is gravel with a continuous gradation of 5-25 mm; the cement is ordinary Portland cement of P·O42.5 grade; and the fly ash is Grade II ash. The method for preparing the concrete material for the reservoir edge protection waterproof layer comprises the following steps: According to the mass proportions, cement, coarse aggregate, fine aggregate, hydrophobically modified polypropylene fiber, fly ash and mineral powder were first poured into a concrete mixer and dry-mixed for 2 minutes. After mixing evenly, water was added and mixed for 2 minutes. Then, a high-efficiency water reducer and silicone-modified acrylic emulsion were added and stirred for 3 minutes to obtain the concrete material for the reservoir side protection waterproof layer.

[0032] Example 3 A concrete material for a reservoir edge protection waterproof layer comprises the following raw materials, calculated by mass: 190 parts of cement, 870 parts of fine aggregate, 940 parts of coarse aggregate, 83 parts of fly ash, 63 parts of mineral powder, 14 parts of hydrophobically modified polypropylene fiber, 13 parts of organosilicon-modified acrylic emulsion, 4 parts of high-efficiency water reducer, and 210 parts of water, wherein the mineral powder is the modified manganese slag powder prepared in Preparation Example 1, the fine aggregate is quartz sand with a particle size of 0.5-0.9 mm; the coarse aggregate is gravel with a continuous gradation of 5-25 mm; the cement is ordinary Portland cement of P·O42.5 grade; and the fly ash is Grade II ash. The method for preparing the concrete material for the reservoir edge protection waterproof layer comprises the following steps: According to the mass proportions, cement, coarse aggregate, fine aggregate, hydrophobically modified polypropylene fiber, fly ash and mineral powder were first poured into a concrete mixer and dry-mixed for 1.8 minutes. After mixing evenly, water was added and mixed for 1.5 minutes. Then, a high-efficiency water reducer and silicone-modified acrylic emulsion were added and stirred for 2.3 minutes to obtain the concrete material for the reservoir side protection waterproof layer.

[0033] Comparative Example 1 The same as Example 3, except that an equal amount of unmodified polypropylene fibers (with a diameter of 0.5 mm and a length of 12 mm) were used instead of the hydrophobically modified polypropylene fibers.

[0034] Comparative Example 2 The same as Example 3, except that the mineral powder is the modified manganese slag powder prepared in Comparative Example 1.

[0035] Comparative Example 3 The same as Example 3, except that the amount of organosilicon-modified acrylic emulsion is 0 parts.

[0036] Performance Testing 1. The reservoir side protection waterproof layer prepared in Examples 1 to 3 and Comparative Examples 1 to 5 was made into a concrete specimen using concrete material. The concrete specimen was a cube with a side length of 100 mm. The surface was sealed with a polyurethane film and cured at room temperature for 24 hours. The mold was then removed and moved to a standard curing box for curing to the corresponding age. The following tests were performed. The test results are shown in Table 1.

[0037] Compressive strength and flexural strength determination: After curing for 28 days according to the specimen standard, test according to the national standard GB / T17671-2021; Number of cracks: Use GB / T50081-2016 "Standard for Test Methods of Mechanical Properties of Ordinary Concrete" to calculate the number of cracks per unit area measured 24 hours after concrete pouring; The impermeability grade is determined according to GB / T50082-2009 "Standard for Test Methods of Long-term Performance and Durability of Ordinary Concrete" after the specimens have been cured for 28 days. 2. Bond strength: The reservoir edge protection waterproof layer prepared in Examples 1 to 3 and Comparative Examples 1 to 5 was coated on the old concrete surface with a concrete material. After curing, a 2.0 mm thick waterproof layer was obtained. After standing for 28 days, the JGJ / T70-2009 standard was tested. The test results are shown in Table 1.

[0038] Table 1 Performance test Analyzing the data in Table 1, we can see that: 1) The concrete materials for reservoir edge protection waterproofing prepared in Examples 1-3 exhibit excellent mechanical strength, bonding strength, impermeability, and crack resistance. The concrete materials for reservoir edge protection waterproofing prepared in the application have the advantages of simple production, low cost, and long service life.

[0039] 2) A comparative analysis of the performance of the concrete materials for the reservoir edge protection waterproof layer prepared in Example 3 and Comparative Example 1 shows that the hydrophobically modified polypropylene fiber of the present application is sequentially hydrophobically modified using an aminosilane coupling agent and trifluoroacetic anhydride, introducing a trifluoromethyl group to impart hydrophobic properties to the polypropylene fiber. This improves the mechanical strength of the concrete material while also improving the toughness and impermeability of the concrete. The hydrophobic polypropylene fiber not only solves the problems of poor compatibility and susceptibility to corrosion of traditional fibers with cement matrices, but also, through functional design and multi-component synergy, enables the comprehensive performance of the concrete to meet the stringent requirements of reservoir slope protection projects for high strength, high durability, impermeability, and crack resistance.

[0040] 3) A comparative analysis of the performance of the concrete materials for the reservoir edge protection waterproof layer prepared in Example 3 and Comparative Example 2 shows that the modified manganese slag powder prepared in this application is obtained by uniformly mixing electrolytic manganese slag, mullite, and fly ash, then soaking in potassium hydroxide solution and hydrogen peroxide, and then sintering at high temperature and grinding into powder. Mullite acts as a crystal nucleus to induce recrystallization of aluminosilicate, forming a high-temperature resistant skeleton, demonstrating the key role of mullite in inducing crystallization during the sintering process. Modified manganese slag powder can significantly improve the compressive strength and flexural strength of concrete materials. At the same time, combined with hydrophobically modified polypropylene fiber and silicone-modified acrylic emulsion, it can further improve the compressive strength, flexural strength, bonding strength, impermeability, and crack resistance of concrete materials.

[0041] 4) A comparative analysis of the performance of the concrete materials for the reservoir edge waterproofing layer prepared in Example 3 and Comparative Example 3 shows that the addition of the organosilicon-modified acrylic emulsion prepared in this application, the epoxy groups contained therein can be combined with the cement molecules through chemical bonding, filling some of the micropores of the concrete to a certain extent. In addition, the organosilicon-modified acrylic emulsion can form a hydrophobic protective layer on the concrete surface to prevent the expansion of surface cracks. The organosilicon-modified acrylic can also improve the bonding strength and impermeability between the concrete material for the waterproofing layer and the base concrete, and also enhance its mechanical properties.

[0042] The above embodiments are only used to illustrate the technical solutions of the present application and are not intended to limit the present application. Although the above embodiments provide a detailed description of the present application, relevant technical personnel should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modifications and equivalent replacements that do not depart from the spirit and scope of the present application should be included in the scope of protection of the present application.

Claims

1. A concrete material for a reservoir edge protection waterproof layer, characterized in that: The preparation method includes the following raw materials in parts by mass: 180-200 parts of cement, 850-900 parts of fine aggregate, 920-960 parts of coarse aggregate, 78-85 parts of fly ash, 60-65 parts of mineral powder, 12-15 parts of hydrophobically modified polypropylene fiber, 12-15 parts of silicone-modified acrylic emulsion, 3-5 parts of high-efficiency water reducer, and 200-220 parts of water, wherein the mineral powder is modified manganese slag powder.

2. The concrete material for a reservoir edge protection waterproof layer according to claim 1, characterized in that: The preparation method of the modified manganese slag powder comprises the following steps: S21. Mix 100 parts of electrolytic manganese slag, 40-45 parts of mullite, and 60-65 parts of fly ash in parts by mass to obtain a mixture A; S22. Mix 100 parts of mixture A, 8-9 parts of 25% potassium hydroxide solution, 8-9 parts of 25% hydrogen peroxide solution, and 200 parts of deionized water, in parts by mass; heat to 65° C. for 6-7 hours, then naturally cool, filter, and dry to obtain mixture B. S23. Place the mixture B in a muffle furnace, sinter at 950-980° C. for 120-150 minutes, cool naturally, grind into powder, and sieve to obtain modified manganese slag powder with an average particle size of 6-9 μm.

3. The concrete material for a reservoir edge protection waterproof layer according to claim 1, characterized in that: The preparation method of the hydrophobically modified polypropylene fiber comprises the following steps: S31, adding 10 parts by mass of polypropylene fiber to 50 parts by mass of 75% ethanol aqueous solution, adjusting the pH to 4-5, adding 0.8 parts of aminosilane coupling agent, stirring and reacting for 3-4 hours, filtering, washing with water, and drying to obtain silane-modified polypropylene fiber; S32. According to the mass fractions, 20 parts of 3% trifluoroacetic anhydride dimethylformamide solution were heated to 90°C, 10 parts of silane-modified polypropylene fibers were added, and the pH value of the dispersion was adjusted to 9-10 with a 10% sodium hydroxide aqueous solution. The mixture was reacted at a constant temperature for 5-6 hours, filtered, washed with water, and dried to obtain hydrophobically modified polypropylene fibers.

4. The concrete material for a reservoir edge protection waterproof layer according to claim 3, characterized in that: The aminosilane coupling agent is one of 3-aminopropyltrihydroxysilane coupling agent and γ-aminopropyltrimethoxysilane.

5. The concrete material for a reservoir edge protection waterproof layer according to claim 1, characterized in that: The preparation method of the organosilicon-modified acrylic emulsion comprises the following steps: S51. Under a nitrogen atmosphere, add bisdimethylsilylamine and ethanol to a reaction flask according to their mass fractions, stir evenly, then add perfluorooctyl chloride and sodium hydride, stir, raise the temperature to 86-90° C., react for 12-14 hours, distill under reduced pressure, and purify by column chromatography to obtain an alkenyl organosilicone fluorine monomer; S52. In a nitrogen atmosphere, add isopropyl alcohol, acrylic acid, butyl methacrylate, epoxy resin E-44 and alkenyl organosilicon fluorine monomer into the reaction flask according to their mass parts. After they are completely dissolved, add azobisisobutyronitrile, raise the temperature to 85-90°C and react for 4-5 hours, cool to 40-43°C, add triethylamine to neutralize, and add deionized water to disperse under high-speed stirring to obtain an organosilicon-modified acrylic emulsion.

6. The concrete material for a reservoir edge protection waterproof layer according to claim 5, characterized in that: In step S51, the mass ratio of bisdimethylsilylamine, ethanol, perfluorooctyl chloride, and sodium hydride is 1:(35-38):(2.8-3):(0.22-0.28).

7. The concrete material for a reservoir edge protection waterproof layer according to claim 5, characterized in that: In step S52, the mass ratio of the isopropyl alcohol, acrylic acid, butyl methacrylate, epoxy resin E-44, alkenyl organosilicone fluorine monomer, azobisisobutyronitrile, triethylamine and deionized water is 100:13:37:(9-11):(8-10):(0.8-1.2):(2.5-3):

85.

8. The concrete material for a reservoir edge protection waterproof layer according to claim 1, characterized in that: The fine aggregate is quartz sand with a particle size of 0.5-0.9 mm; the coarse aggregate is gravel with a continuous grading of 5-25 mm.

9. The concrete material for a reservoir edge protection waterproof layer according to claim 1, characterized in that: The cement is P·O42.5 grade ordinary Portland cement; the high-efficiency water reducer is ZWL-A-IX type water reducer; and the fly ash is grade II ash.

10. A method for preparing a concrete material for a reservoir edge protection waterproof layer according to any one of claims 1 to 9, characterized in that: The following steps are involved: According to the mass proportions, cement, coarse aggregate, fine aggregate, hydrophobically modified polypropylene fiber, fly ash and mineral powder are first poured into a concrete mixer and dry-mixed for 1.5-2 minutes. After mixing evenly, water is added and mixed for 1-2 minutes. Then, a high-efficiency water reducer and silicone-modified acrylic emulsion are added and stirred for 2-3 minutes to obtain the concrete material for the reservoir side protection waterproof layer.

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