Granite high-strength concrete and preparation method thereof

Abstract

The invention belongs to the technical field of building materials, and particularly discloses granite high-strength concrete and a preparation method thereof. The granite high-strength concrete is prepared from the following raw materials in parts by weight: 110 to 130 parts of cement, 70 to 80 parts of glass micropowder, 90 to 100 parts of fly ash, 200 to 220 parts of modified waste granite powder, 250 to 300 parts of water, 180 to 190 parts of modified bamboo sawdust, 400 to 420 parts of sand, 500 to 520 parts of stone, 10 to 15 parts of polycarboxylate superplasticizer and 30 to 40 parts of iron tailings. Various raw materials in the concrete are mixed, the materials play an important role in the granite high-strength concrete, the strength and durability of the concrete are improved, and the concrete material with excellent performance is prepared.

Description

Technical Field

[0001] This application relates to the technical field of building materials, and particularly relates to a high-strength granite concrete and a preparation method thereof. Background Art

[0002] Waste granite stones, mainly the waste generated during the mining and processing of granite, are mainly composed of minerals such as quartz and feldspar. These minerals endow granite with excellent properties such as hardness, wear resistance, and corrosion resistance. Therefore, after waste granite stones are crushed, screened, etc., they can be used as recycled aggregates in the preparation of building materials such as concrete and mortar. This can not only reduce the extraction volume of natural aggregates but also reduce construction costs.

[0003] Traditional concrete, as a material widely used in the construction field, has a series of advantages but also has some disadvantages. Traditional concrete is usually composed of cement, water, sand, and stones, and has the advantages of high compressive strength and good durability. However, when concrete materials are faced with complex and changeable engineering environments, they often show disadvantages such as insufficient tensile strength, poor toughness, and easy generation of cracks, thereby reducing the application of concrete materials. Summary of the Invention

[0004] In order to improve the problem of poor tensile strength of concrete materials, this application provides a high-strength granite concrete and a preparation method thereof.

[0005] This application provides a high-strength granite concrete, adopting the following technical solution: A high-strength granite concrete, by weight, comprises the following raw materials: 110 - 130 parts of cement, 70 - 80 parts of glass powder, 90 - 100 parts of fly ash, 200 - 220 parts of modified waste granite powder, 250 - 300 parts of water, 180 - 190 parts of modified bamboo chips, 400 - 420 parts of sand, 500 - 520 parts of stones, 10 - 15 parts of polycarboxylate water reducer, and 30 - 40 parts of iron tailings.

[0006] By adopting the above technical solution, cement, as a bonding material, forms a paste after being stirred with water and can firmly bond other materials together to form a solid building structure; glass powder has pozzolanic activity and reacts with the calcium hydroxide in the cement hydration product to form calcium silicate hydrate, reducing the content of calcium hydroxide and increasing the content of calcium silicate hydrate, thereby improving the strength of the concrete. Fly ash can significantly improve the workability of the concrete, increase the volume of the fresh concrete paste, effectively fill the voids between the aggregates, and lubricate the aggregate particles to ensure the uniformity and stability of the fresh concrete.

[0007] The modified waste granite powder plays a role of micro-aggregate filling in concrete. It can react with the components in cement to generate calcium aluminate hydrate, making the cement stone structure more dense, improving the internal density of concrete, and thus enhancing the compressive strength and tensile strength of concrete. The modified bamboo chips have good filling performance. When filled in the concrete system structure, they can increase the toughness, tensile strength and stability of concrete. As the fine aggregate in concrete, sand can fill the voids between cement and gravel, improving the density and strength of concrete. Gravel injects more stability and hardness into concrete, improving the strength and quality of concrete.

[0008] The polycarboxylate superplasticizer has the advantages of high water reduction rate and low dosage. It can significantly improve the workability and mechanical strength of concrete. It can also disperse cement particles and prevent the rapid formation of cement flocculation structure, thus maintaining the fluidity of concrete. Iron tailings can improve the early strength of concrete, reduce the cost of concrete, and improve the mechanical properties and durability of concrete. When various raw materials in concrete are mixed, these materials play important roles respectively in high-strength granite concrete, improving the strength and durability of concrete and preparing concrete materials with excellent performance.

[0009] Preferably, the preparation method of the modified waste granite powder includes the following steps: (1) Disperse the waste granite in sodium hydroxide solution, stir for 1 - 2 h, then disperse it in hydrochloric acid solution, stir for 2 - 3 h, wash with water, then disperse it in absolute ethanol, stir for 10 - 15 min, filter and dry to obtain pretreated granite; (2) Crush the pretreated granite obtained in step (1) to obtain particles with a particle size of 0.5 - 1 cm, then grind to obtain fine stone powder with a particle size of 10 - 20 μm, then disperse it in deionized water, add sodium silicate, and stir for 4 - 5 h to obtain activated fine powder; (3) Disperse the activated fine powder obtained in step (2) in deionized water, add modified glass fiber, sodium dodecyl sulfate, and hydroxypropyl methylcellulose, and stir at a temperature of 50 - 55 °C for 2 - 3 h, then dry to obtain the modified waste granite powder.

[0010] By adopting the above technical solution, the waste granite is dispersed in sodium hydroxide solution to remove certain impurities on the surface of granite and conduct preliminary etching on the granite. Then, the treated granite is dispersed in hydrochloric acid solution for further etching and adjustment of the surface properties of the granite. Then, the washed granite is dispersed in absolute ethanol, filtered and dried to obtain pretreated granite.

[0011] The pre-treated granite is crushed into particles with a particle size of 0.5 - 1 cm, ground to obtain fine stone powder, the fine stone powder is dispersed in deionized water, and sodium silicate is added. The colloid formed after sodium silicate dissolves in water has viscosity, which can fill the voids in the fine stone powder, increasing the overall density. Cross-linking reactions occur between the silicic acid colloid particles to form a three-dimensional network structure, enhancing the strength of the fine stone powder. Moreover, the colloidal property of sodium silicate also contributes to the dispersion and stability of the fine stone powder particles.

[0012] The activated fine powder is dispersed in deionized water. The modified glass fiber has high strength and good toughness, and can be loaded on the surface of the fine powder particles, significantly improving the overall mechanical properties of the mixture, playing a role in strengthening and toughening. Sodium dodecyl sulfate has the ability to reduce surface tension and disperse particles, contributing to the uniform dispersion of each component, making the modified glass fiber and the fine powder particles mix evenly. Hydroxypropyl methylcellulose has thickening and stabilizing properties, can increase the viscosity of the mixture, prevent particle sedimentation and stratification. Hydroxypropyl methylcellulose forms hydrogen bonds with certain functional groups on the surface of granite powder or glass fiber through its hydroxyl groups, thereby enhancing the binding force between components, making the modified glass fiber and the fine powder particles adhere tightly, and improving the stability, compressive strength and tensile strength of the mixture. The obtained modified waste granite powder has excellent strength, toughness and stability.

[0013] Preferably, the mass ratio of the waste granite, modified glass fiber and hydroxypropyl methylcellulose is 1:0.5 - 0.7:0.1 - 0.3.

[0014] By adopting the above technical scheme, further limiting the mass ratio of the waste granite, modified glass fiber and hydroxypropyl methylcellulose within a certain range, the obtained modified waste granite has excellent comprehensive properties. The waste granite has good wear resistance and strength, the modified glass fiber has high strength and toughness, and can be loaded on the surface of the waste granite particles to form a three-dimensional network structure, increasing the strength, toughness and durability of the waste granite. Hydroxypropyl methylcellulose has a certain viscosity, making the modified glass fiber and the waste granite adhere tightly, improving the density of the waste granite. Subsequently, it is applied to concrete, filling the pores and micro-cracks in the concrete to form a colloidal protective layer, improving the tensile strength, compressive strength and flexural strength of the concrete, making the concrete more solid and durable.

[0015] The waste granite, modified glass fiber and hydroxypropyl methylcellulose cooperate with each other to have a synergistic effect, jointly improving the corresponding properties of the waste granite. The waste granite, glass fiber and hydroxypropyl methylcellulose are mixed in the concrete, which can significantly improve the mechanical properties of the concrete, improve the construction performance, and enhance the durability and environmental protection.

[0016] Preferably, the preparation method of the modified glass fiber comprises the following steps: heating the glass fiber at a temperature of 500-550°C for 30-35 min, then dispersing it in absolute ethanol containing 4-6% by mass of coupling agent KH570, stirring for 10-15 min, drying, and then dispersing it in deionized water. Adding nano-silica, gelatin and polyvinyl alcohol, and performing ultrasonic treatment at a temperature of 60-65°C for 2-3 h, and then drying to obtain the modified glass fiber.

[0017] By adopting the above technical solution, heating the glass fiber helps to remove impurities on its surface, change the chemical composition and physical structure of the glass fiber surface, improve the heat resistance performance, and create favorable conditions for subsequent surface modification. The coupling agent KH570 can chemically react with functional groups such as hydroxyl groups on the glass fiber surface to form chemical bonding, change the compatibility and bonding force between the glass fiber and other materials, and contribute to the composite with other materials.

[0018] Nano-silica has good strength and wear resistance, can be loaded on the surface and surface pores of the glass fiber, enhance the wear resistance and hardness of the glass fiber. Gelatin has a certain viscosity, enabling the nano-silica to stably adhere to the structure of the glass fiber, increasing the performance stability of the glass fiber. Polyvinyl alcohol has good dispersibility, which helps to improve the dispersibility of the glass fiber and nano-silica, enabling the nano-silica to be evenly loaded in the structure of the glass fiber, and improving the comprehensive performance of the glass fiber. The modified glass fiber has higher strength, hardness and wear resistance, and when applied to concrete, can significantly improve the mechanical properties of the concrete.

[0019] Preferably, the preparation method of the modified wood chips comprises the following steps: (1) Grinding the wood chips into powder, then dispersing them in an ethanol solution, stirring at a temperature of 60-65°C for 20-25 min, adding potassium hydroxide, calcium carbonate and sodium methoxide, continuing to stir for 10-15 min, filtering and drying to obtain pretreated wood chip powder; (2) Dispersing the modified graphene in deionized water, adding polyvinylpyrrolidone, stirring for 15-20 min, and then adding the pretreated wood chip powder in step (1), performing ultrasonic treatment for 2-3 h, filtering, and drying to obtain a mixture; (3) Spraying an aqueous sodium alginate solution on the surface of the mixture in step (2), and drying to obtain the modified wood chips.

[0020] By adopting the above technical solution, the strong alkalinity of potassium hydroxide alkalizes the wood chips, changes the charge property and hydrophilicity / hydrophobicity of their surfaces, and facilitates subsequent applications; the addition of calcium carbonate plays a filling role, increasing the density and hardness of the system; sodium methoxide can be used as a solvating reagent to promote the dissolution and dispersion of wood chips in ethanol solution. The modified wood chip powder has better adsorption performance, which helps to mix with other components subsequently.

[0021] The modified graphene has good mechanical properties and wear resistance. Polyvinylpyrrolidone can be adsorbed on the surface of graphene sheets and prevent the agglomeration of graphene sheets through steric hindrance effect, thereby improving the dispersion stability of graphene in water. The modified graphene can be evenly loaded on the surface of wood chip powder particles, increasing the strength and hardness of the wood chip powder. Spraying an aqueous sodium alginate solution on the surface of the mixture, the aqueous sodium alginate solution has good viscosity and film-forming property, and can coat the modified graphene and wood chip powder, making the wood chip powder and the modified graphene adhere tightly, increasing the performance stability of the modified wood chips, and making the modified wood chips have better mechanical properties and wear resistance. Subsequently, it is applied to concrete to increase the mechanical properties, compressive strength, tensile strength and durability of the concrete.

[0022] Preferably, the mass ratio of the wood chips, the modified graphene and the aqueous sodium alginate solution is 1 g: 100 - 110 mg: 0.3 - 0.5 g.

[0023] By adopting the above technical solution, further limiting the mass ratio of the wood chips, the modified graphene and the aqueous sodium alginate solution within a certain range, the obtained wood chips have better mechanical properties and durability. The modified graphene has the characteristics of high strength and high toughness, can be loaded on the surface of wood chip particles, increasing the mechanical properties and wear resistance of the wood chips. The aqueous sodium alginate solution has certain viscosity, making the wood chips and the modified graphene adhere tightly, further increasing the comprehensive performance of the wood chips. Subsequently, it is applied to concrete, effectively enhancing the mechanical properties of the concrete. The sheet structure of the modified graphene can form a "bridge effect" in the concrete, improving the crack resistance and durability of the concrete. The filling effect of the wood chips increases the density and uniformity of the concrete, reduces the shrinkage and crack generation of the concrete, and improves the impermeability and durability of the concrete. The aqueous sodium alginate solution has good viscosity and film-forming property, improves the fluidity of the concrete, reduces the shrinkage and cracking of the concrete, and improves the durability and service life of the concrete.

[0024] Preferably, the preparation method of the modified graphene includes the following steps: dispersing graphene in a tetrahydrofuran solution, ultrasonically stirring for 20 - 30 min to obtain a graphene suspension; adding nano-copper oxide and sodium alkylphenol polyoxyethylene ether sulfate to the graphene suspension, ultrasonically stirring for 30 - 35 min, drying, and grinding to obtain graphene powder; dispersing the graphene powder in deionized water, adding nano-titanium nitride, polyethylene glycol, stearic acid, and a water-based epoxy resin adhesive, ultrasonically treating for 4 - 5 h, and drying to obtain modified graphene.

[0025] By adopting the above technical solution, graphene is dispersed in a tetrahydrofuran solution, so that the graphene sheets are uniformly dispersed in the tetrahydrofuran solution to form a stable suspension. Adding nano-copper oxide and sodium alkylphenol polyoxyethylene ether sulfate, the interaction between nano-copper oxide and graphene further improves the dispersibility and stability of graphene. Sodium alkylphenol polyoxyethylene ether sulfate acts as a surfactant to reduce the surface tension of the solution, which helps the dispersion and stability of nanoparticles.

[0026] Dispersing the graphene powder in deionized water, adding nano-titanium nitride, polyethylene glycol, stearic acid, and a water-based epoxy resin adhesive. Nano-titanium nitride has good mechanical properties and can be loaded on the surface of graphene to improve the strength and durability of graphene. Polyethylene glycol has good dispersibility and stability, making the graphene and nano-titanium nitride evenly dispersed. Stearic acid improves the fluidity of the system and reduces the friction between particles. The water-based epoxy resin adhesive has excellent bonding properties, enhancing the bonding force between the internal particles of the material, making nano-titanium nitride stably bonded to the surface of the graphene powder, and increasing the overall strength of graphene. Subsequently, when applied to concrete, it forms a continuous bonding layer in the concrete, enhancing the overall strength of the concrete, increasing the hardness of the concrete surface, and improving its durability, chemical resistance, and wear resistance, filling the fine cracks on the concrete surface, thereby enhancing the crack resistance of the concrete.

[0027] Preferably, the specific surface area of the glass micro-powder is 430 - 450 m2 / kg, and the average particle size is 15 - 20 μm.

[0028] By adopting the above technical solution, limiting the specific surface area and average particle size of the glass micro-powder makes the glass micro-powder easier to be uniformly dispersed in the matrix, with more surface activity and reaction sites, and more effectively filling the voids in the material, thereby improving the overall performance of the material.

[0029] Preferably, the fineness modulus of the sand is 2.5 - 2.8, and the gravel is continuous-grading gravel with a particle size range of 6 - 10 mm.

[0030] By adopting the above technical solution, further limiting the fineness modulus of the sand and the particle size of the gravel, the obtained sand and gravel have broad application prospects and excellent performance in the fields of construction and engineering.

[0031] In a second aspect, the present application also provides a method for preparing high-strength granite concrete, comprising the following steps: mixing cement, glass powder, fly ash, modified waste granite powder, water, modified bamboo chips, and iron tailings, then adding sand and gravel, and after mixing, obtaining a mixture, and then adding a polycarboxylate water reducer and mixing to obtain high-strength granite concrete.

[0032] By adopting the above technical solution and preparation method, the operation is simple, the process time is short, which helps to improve the production efficiency of preparing high-strength granite concrete, and the obtained high-strength granite concrete has good mechanical properties.

[0033] In summary, the present application has the following beneficial effects: 1. In the present application, various raw materials in the concrete are mixed, and these materials play important roles in high-strength granite concrete respectively, improving the strength and durability of the concrete and preparing excellent concrete materials.

[0034] 2. In the present application, the modified waste granite powder plays a role of micro-aggregate filling in the concrete, can react with the components in the cement to generate calcium aluminocarbonate hydrate, making the cement stone structure more dense, improving the internal density of the concrete, and thus improving the compressive strength and tensile strength of the concrete.

[0035] 3. In the present application, the modified bamboo chips have good filling properties, fill the concrete system structure, and increase the toughness, tensile strength and stability of the concrete. Specific Embodiments

[0036] The following further elaborates on the present application with reference to embodiments.

[0037] The raw materials used in the examples and comparative examples can all be obtained commercially.

[0038] Preparation Example of Modified Waste Granite Powder Preparation Example 1-1 The preparation method of the modified waste granite powder comprises the following steps: (1) Dispersing 250 kg of waste granite in 300 L of a sodium hydroxide solution with a mass fraction of 3%, stirring for 1.5 h, then dispersing in 320 L of a hydrochloric acid solution with a mass fraction of 6%, stirring for 2.5 h, washing with water, then dispersing in 300 L of absolute ethanol, stirring for 13 min, filtering, and drying to obtain pretreated granite; (2) Crushing the pretreated granite obtained in step (1) to obtain particles with a particle size of 0.5 - 1 cm, then grinding to obtain fine stone powder with a particle size of 10 - 20 μm, and then dispersing in 290 L of deionized water, adding 90 kg of sodium silicate, and stirring for 4.5 h to obtain activated fine powder; (3) Disperse the activated fine powder obtained in step (2) in 1000 L of deionized water, add modified glass fiber, 20 kg of sodium dodecyl sulfate, and hydroxypropyl methylcellulose, stir at a temperature of 55 °C for 3 h, and then dry to obtain modified waste granite powder.

[0039] The mass ratio of waste granite, modified glass fiber, and hydroxypropyl methylcellulose is 1:0.5:0.3.

[0040] The preparation method of modified glass fiber includes the following steps: Heat 220 kg of glass fiber at a temperature of 530 °C for 35 min, then disperse it in 300 L of absolute ethanol containing 5% by mass of coupling agent KH570, stir for 12 min, dry, and then disperse it in 600 L of deionized water. Add 126 kg of nano-silica, 30 kg of gelatin, and 14 kg of polyvinyl alcohol, and ultrasonicate at a temperature of 65 °C for 2.5 h, and then dry to obtain modified glass fiber.

[0041] Preparation Example 1-2 The difference from Preparation Example 1-1 is that in step (3), no modified glass fiber is added.

[0042] Preparation Example 1-3 The difference from Preparation Example 1-1 is that in step (3), no hydroxypropyl methylcellulose is added.

[0043] Preparation Example 1-4 The difference from Preparation Example 1-1 is that the mass ratio of waste granite, modified glass fiber, and hydroxypropyl methylcellulose is 1:0.7:0.1.

[0044] Preparation Example 1-5 The difference from Preparation Example 1-1 is that the mass ratio of waste granite, modified glass fiber, and hydroxypropyl methylcellulose is 1:0.1:0.8.

[0045] Preparation Example 1-6 The difference from Preparation Example 1-1 is that in the preparation method of modified glass fiber, no nano-silica is added.

[0046] Preparation Example 1-7 The difference from Preparation Example 1-1 is that in the preparation method of modified glass fiber, no gelatin is added.

[0047] Preparation Example of Modified Wood Chips Preparation Example 2-1 The preparation method of modified wood chips includes the following steps: (1) Grind 230 kg of wood chips into powder, then disperse it in 400 L of ethanol solution, stir at 62 °C for 23 min, add 10 kg of potassium hydroxide, 30 kg of calcium carbonate and 29 kg of sodium methoxide, continue to stir for 14 min, filter and dry to obtain pretreated wood chip powder; (2) Disperse the modified graphene in 700 L of deionized water, add 5 kg of polyvinylpyrrolidone, stir for 17 min, then add the pretreated wood chip powder in step (1), ultrasonicate for 2.5 h, filter and dry to obtain a mixture; (3) Spray an aqueous sodium alginate solution on the surface of the mixture in step (2), and dry to obtain modified wood chips.

[0048] The mass ratio of wood chips, modified graphene and aqueous sodium alginate solution is 1 g: 100 mg: 0.5 g.

[0049] The aqueous sodium alginate solution is prepared by dissolving 130 kg of sodium alginate in 350 L of deionized water and stirring evenly. Select the required amount for the preparation of modified wood chips.

[0050] The preparation method of modified graphene includes the following steps: Disperse 30 kg of graphene in 50 L of tetrahydrofuran solution, ultrasonically stir for 25 min to obtain a graphene suspension; Add 7 kg of nano-copper oxide and 6 kg of sodium alkylphenol polyoxyethylene ether sulfate to the graphene suspension, ultrasonically stir for 33 min, dry and grind to obtain graphene powder; Disperse the graphene powder in 200 L of deionized water, add 12 kg of nano-titanium nitride, 5 kg of polyethylene glycol, 3 kg of stearic acid and 8 kg of water-based epoxy resin adhesive, ultrasonicate for 4.5 h, and dry to obtain modified graphene; Among them, the water-based epoxy resin adhesive is purchased from Shanghai Shouxing Industry Co., Ltd.

[0051] Preparation Example 2-2 The difference from Preparation Example 2-1 is that in step (2), modified graphene is not added.

[0052] Preparation Example 2-3 The difference from Preparation Example 2-1 is that in step (3), the aqueous sodium alginate solution is not added.

[0053] Preparation Example 2-4 The difference from Preparation Example 2-1 is that the mass ratio of wood chips, modified graphene and aqueous sodium alginate solution is 1 g: 110 mg: 0.3 g.

[0054] Preparation Example 2-5 The difference from Preparation Example 2-1 is that the mass ratio of wood chips, modified graphene and aqueous sodium alginate solution is 1 g: 90 mg: 0.9 g.

[0055] Preparation Example 2-6 It is different from Preparation Example 2-1 in that in the preparation method of the modified graphene, nano-titanium nitride is not added.

[0056] Preparation Example 2-7 It is different from Preparation Example 2-1 in that in the preparation method of the modified graphene, water-based epoxy resin adhesive is not added. Examples

[0057] Example 1 A kind of high-strength granite concrete, by weight, includes the following raw materials: 110 kg of cement, 80 kg of glass powder, 90 kg of fly ash, 220 kg of modified waste granite powder, 250 kg of water, 190 kg of modified bamboo chips, 400 kg of sand, 520 kg of stones, 10 kg of polycarboxylate water reducer, 40 kg of iron tailings; Among them, the specific surface area of the glass powder is 440 m 2 / kg, and the average particle size is 17 μm.

[0058] The fineness modulus of the sand is 2.7, and the stones are continuously graded crushed stones with a particle size of 8 mm.

[0059] The preparation method of the above-mentioned high-strength granite concrete includes the following steps: Mix cement, glass powder, fly ash, modified waste granite powder, water, modified bamboo chips, and iron tailings, then add sand and stones, and after mixing, obtain a mixture, and then add polycarboxylate water reducer and mix to obtain high-strength granite concrete.

[0060] The modified waste granite powder is prepared by Preparation Example 1-1, and the modified wood chips are prepared by Preparation Example 2-1.

[0061] Example 2 A kind of high-strength granite concrete, different from Example 1, by weight, includes the following raw materials: 130 kg of cement, 70 kg of glass powder, 100 kg of fly ash, 200 kg of modified waste granite powder, 300 kg of water, 180 kg of modified bamboo chips, 420 kg of sand, 500 kg of stones, 15 kg of polycarboxylate water reducer, 30 kg of iron tailings.

[0062] Example 3 A kind of high-strength granite concrete, different from Example 1, the modified waste granite powder is prepared by Preparation Example 1-2.

[0063] Example 4 A kind of high-strength granite concrete, different from Example 1, the modified waste granite powder is prepared by Preparation Example 1-3.

[0064] Example 5 A kind of high-strength granite concrete, different from Example 1 in that the modified waste granite powder is prepared by Preparation Examples 1-4.

[0065] Example 6 A kind of high-strength granite concrete, different from Example 4 in that the modified waste granite powder is prepared by Preparation Examples 1-5.

[0066] Example 7 A kind of high-strength granite concrete, different from Example 4 in that the modified waste granite powder is prepared by Preparation Examples 1-6.

[0067] Example 8 A kind of high-strength granite concrete, different from Example 4 in that the modified waste granite powder is prepared by Preparation Examples 1-7.

[0068] Example 9 A kind of high-strength granite concrete, different from Example 4 in that the modified wood chips are prepared by Preparation Example 2-2.

[0069] Example 10 A kind of high-strength granite concrete, different from Example 4 in that the modified wood chips are prepared by Preparation Example 2-3.

[0070] Example 11 A kind of high-strength granite concrete, different from Example 4 in that the modified wood chips are prepared by Preparation Example 2-4.

[0071] Example 12 A kind of high-strength granite concrete, different from Example 4 in that the modified wood chips are prepared by Preparation Example 2-5.

[0072] Example 13 A kind of high-strength granite concrete, different from Example 4 in that the modified wood chips are prepared by Preparation Example 2-6.

[0073] Example 14 A kind of high-strength granite concrete, different from Example 4 in that the modified wood chips are prepared by Preparation Example 2-7.

[0074] Comparative Example Comparative Example 1 A kind of high-strength granite concrete, different from Example 1 in that no modified waste granite powder is added.

[0075] Comparative Example 2 A kind of high-strength granite concrete, different from Example 1 in that an equal amount of waste granite powder is used to replace the modified waste granite powder.

[0076] Comparative Example 3 A kind of granite high-strength concrete, which is different from that in Example 1 in that modified bamboo chips are not added.

[0077] Comparative Example 4 A kind of granite high-strength concrete, which is different from that in Example 1 in that equal amounts of wood chips are used to replace the modified wood chips.

[0078] Performance detection test The granite high-strength concrete prepared in Examples 1-14 and Comparative Examples 1-4 was subjected to performance testing; Referring to GB / T50081-2019 "Standard for Test Methods of Physical and Mechanical Properties of Concrete", the compressive strength, flexural strength and tensile strength of the concrete were detected. The size of the concrete test block was 10cm×10cm×10cm. The test ages for compressive strength and flexural strength were 7d and 28d, and the test age for tensile strength was 28d.

[0079] Referring to GB / T 50081-2002 "Standard for Test Methods of Mechanical Properties of Ordinary Concrete", the 28d splitting tensile strength of the concrete was tested, and the test results are shown in Table 1.

[0080] Table 1 Test data of examples and comparative examples It can be seen from Table 1 that the granite high-strength concrete prepared in Examples 1-2 of the present application has good mechanical properties and mechanical strength. Among them, the 7d compressive strength of Example 1 reaches 30.1MPa, the 28d compressive strength reaches 49.6MPa, the 7d flexural strength is 10.3MPa, the 28d flexural strength is 25.9MPa, the anti-cracking performance is 6.69MPa, and the 28d tensile strength is 29.8MPa. It can be seen that the concrete prepared in the present application has excellent tensile strength, compressive strength, toughness and anti-cracking performance, improves the strength and durability of the concrete, and prepares a concrete material with excellent performance.

[0081] In the preparation methods of the modified waste granite powder in Examples 3 - 4, modified glass fiber and hydroxypropyl methylcellulose are not added respectively. In Examples 5 - 6, the mass ratios of waste granite, modified glass fiber and hydroxypropyl methylcellulose are changed. As can be seen from Table 1, the test results of the compressive strength at 7 days, the compressive strength at 28 days, the flexural strength at 7 days, the flexural strength at 28 days, the crack resistance and the tensile strength in Examples 3 - 4 are significantly worse than those in Examples 1 - 2 and Example 5. The test results of the corresponding properties in Example 6 are better than those in Examples 3 - 4, but worse than those in Examples 1 - 2 and Example 5. It shows that waste granite has good wear resistance and strength, and modified glass fiber has high strength and toughness, which can be loaded on the surface of waste granite particles to form a three-dimensional network structure, increasing the strength, toughness and durability of waste granite. Hydroxypropyl methylcellulose makes the modified glass fiber and waste granite adhere tightly, improving the compactness of waste granite. Subsequently, it is applied to concrete to fill the pores and microcracks in the concrete, improving the tensile strength, compressive strength and flexural strength of the concrete, making the concrete more solid and durable.

[0082] In the preparation methods of the modified glass fiber in Examples 7 - 8, nano-silica and gelatin are not added respectively. As can be seen from Table 1, the test results of the compressive strength at 7 days, the compressive strength at 28 days, the flexural strength at 7 days, the flexural strength at 28 days, the crack resistance and the tensile strength in Examples 7 - 8 are significantly worse than those in Examples 1 - 2, but better than those in Example 3. It shows that nano-silica has good strength and wear resistance, which can be loaded on the surface and surface pores of glass fiber, enhancing the wear resistance and hardness of glass fiber. Gelatin has a certain viscosity, making nano-silica stably adhere to the structure of glass fiber, increasing the performance stability of glass fiber. The modified glass fiber has higher strength, hardness and wear resistance. When applied to concrete, it can significantly improve the mechanical properties of concrete.

[0083] In the preparation methods of the modified wood chips in Examples 9 - 10, modified graphene and sodium alginate aqueous solution are not added respectively. In Examples 11 - 12, the mass ratios of wood chips, modified graphene and sodium alginate aqueous solution are changed. As can be seen from Table 1, the test results of the compressive strength at 7 days, the compressive strength at 28 days, the flexural strength at 7 days, the flexural strength at 28 days, the crack resistance and the tensile strength in Examples 9 - 10 are significantly worse than those in Examples 1 - 2 and Example 11. The test results of the corresponding properties in Example 12 are better than those in Examples 9 - 10, but worse than those in Examples 1 - 2 and Example 11. It shows that modified graphene has the characteristics of high strength and high toughness, which can be loaded on the surface of wood chip particles, increasing the mechanical properties and wear resistance of wood chips. Sodium alginate aqueous solution has a certain viscosity, making the wood chips and modified graphene adhere tightly, further increasing the comprehensive properties of wood chips. Subsequently, when applied to concrete, it can effectively enhance the mechanical properties, crack resistance and durability of concrete.

[0084] In the preparation methods of the modified graphene in Examples 13 - 14, nano - titanium nitride and water - based epoxy resin adhesive are not added respectively. It can be seen from Table 1 that the test results of the 7 - day compressive strength, 28 - day compressive strength, 7 - day flexural strength, 28 - day flexural strength, crack resistance and tensile strength of Examples 13 - 14 are significantly worse than those of Examples 1 - 2, but better than those of Example 9. It shows that nano - titanium nitride has good mechanical properties and can be loaded on the surface of graphene to improve the strength and durability of graphene; the water - based epoxy resin adhesive has excellent bonding properties, enhances the bonding force between internal particles of the material, enables nano - titanium nitride to stably bond on the surface of graphene powder, increases the overall strength of graphene, and subsequently enhances the overall strength, durability and crack resistance of concrete.

[0085] In Comparative Example 1 and Comparative Example 3, modified waste granite powder and modified bamboo chips are not added respectively. It can be seen from Table 1 that the test results of the 7 - day compressive strength, 28 - day compressive strength, 7 - day flexural strength, 28 - day flexural strength, crack resistance and tensile strength of Comparative Example 1 and Comparative Example 3 are significantly worse than those of Examples 1 - 2, indicating that the modified waste granite powder plays a role of micro - aggregate filling in concrete, making the structure of cement stone more dense, thus improving the compressive strength and tensile strength of concrete. The modified bamboo chips have good filling properties, increasing the toughness, tensile strength and stability of concrete.

[0086] In Comparative Example 2 and Comparative Example 4, equal amounts of waste granite powder are used to replace the modified waste granite powder and equal amounts of wood chips are used to replace the modified wood chips respectively. It can be seen from Table 1 that the test results of the 7 - day compressive strength, 28 - day compressive strength, 7 - day flexural strength, 28 - day flexural strength, crack resistance and tensile strength of Comparative Example 1 and Comparative Example 3 are significantly worse than those of Examples 1 - 2, but better than those of Comparative Example 2 and Comparative Example 4, indicating that the modified waste granite powder and modified wood chips in this application have better mechanical properties, filling in concrete to improve the comprehensive performance of concrete.

[0087] This specific embodiment is only an interpretation of the present application, and it does not limit the present application. After reading this specification, those skilled in the art can make modifications to this embodiment without creative contributions according to needs, but as long as it is within the scope of the claims of the present application, it is protected by the patent law.

Claims

1. A high-strength granite concrete, characterized in that, By weight parts, it includes the following raw materials: 110 - 130 parts of cement, 70 - 80 parts of glass powder, 90 - 100 parts of fly ash, 200 - 220 parts of modified waste granite powder, 250 - 300 parts of water, 180 - 190 parts of modified bamboo chips, 400 - 420 parts of sand, 500 - 520 parts of stones, 10 - 15 parts of polycarboxylate water reducer, and 30 - 40 parts of iron tailings.

2. A high-strength granite concrete according to claim 1, wherein The preparation method of the said modified waste granite powder includes the following steps: (1) Disperse the waste granite in sodium hydroxide solution, stir for 1 - 2 h, then disperse it in hydrochloric acid solution, stir for 2 - 3 h, wash with water, then disperse it in absolute ethanol, stir for 10 - 15 min, filter, and dry to obtain pretreated granite. (2) Crush the pretreated granite in step (1) to obtain particles with a particle size of 0.5 - 1 cm, then grind to obtain fine stone powder with a particle size of 10 - 20 μm, then disperse it in deionized water, add sodium silicate, and stir for 4 - 5 h to obtain activated fine powder. (3) Disperse the activated fine powder in step (2) in deionized water, add modified glass fiber, sodium dodecyl sulfate, and hydroxypropyl methyl cellulose, stir at a temperature of 50 - 55 °C for 2 - 3 h, and dry to obtain modified waste granite powder.

3. A high-strength granite concrete according to claim 2, characterized in that, The mass ratio of the said waste granite, modified glass fiber, and hydroxypropyl methyl cellulose is 1:0.5 - 0.7:0.1 - 0.

3.

4. A high-strength granite concrete according to claim 2, characterized in that The preparation method of the said modified glass fiber includes the following steps: Heat the glass fiber at a temperature of 500 - 550 °C for 30 - 35 min, then disperse it in absolute ethanol with a mass fraction of 4 - 6% of coupling agent KH570, stir for 10 - 15 min, dry, then disperse it in deionized water, add nano - silicon dioxide, gelatin, and polyvinyl alcohol, and ultrasonically treat at a temperature of 60 - 65 °C for 2 - 3 h, and dry to obtain modified glass fiber.

5. A high-strength granite concrete according to claim 1, characterized in that The preparation method of the said modified wood chips includes the following steps: (1) Grind the wood chips into powder, then disperse it in ethanol solution, stir at a temperature of 60 - 65 °C for 20 - 25 min, add potassium hydroxide, calcium carbonate, and sodium methoxide, continue to stir for 10 - 15 min, filter and dry to obtain pretreated wood chip powder. (2) Disperse the modified graphene in deionized water, add polyvinylpyrrolidone, stir for 15 - 20 min, then add the pretreated wood chip powder in step (1), ultrasonically treat for 2 - 3 h, filter, and dry to obtain a mixture. (3) Spray an aqueous sodium alginate solution on the surface of the mixture in step (2), and dry to obtain modified wood chips.

6. A high-strength granite concrete according to claim 5, characterized in that, The mass ratio of the said wood chips, modified graphene, and aqueous sodium alginate solution is 1 g:100 - 110 mg:0.3 - 0.5 g.

7. A high-strength granite concrete according to claim 5, characterized in that, The preparation method of the modified graphene comprises the following steps: dispersing graphene in a tetrahydrofuran solution, and performing ultrasonic stirring for 20-30 min to obtain a graphene suspension; adding nano-copper oxide and sodium alkylphenol polyoxyethylene ether sulfate into the graphene suspension, performing ultrasonic stirring for 30-35 min, drying, and grinding to obtain graphene powder; dispersing the graphene powder in deionized water, adding nano-titanium nitride, polyethylene glycol, stearic acid and a water-based epoxy resin adhesive, performing ultrasonic treatment for 4-5 h, and drying to obtain modified graphene.

8. A high-strength granite concrete according to claim 1, wherein The specific surface area of the glass micropowder is 430-450 m 2 / kg, and the average particle size is 15-20 μm.

9. A high-strength granite concrete according to claim 1, characterized in that The fineness modulus of the sand is 2.5-2.8, and the stone is continuous graded crushed stone with a particle size of 6-10 mm.

10. The preparation method of a high-strength granite concrete according to claim 1, characterized in that, It comprises the following steps: mixing cement, glass powder, fly ash, modified waste granite powder, water, modified bamboo chips and iron tailings, adding sand and stones, mixing, adding a polycarboxylate water reducer, and mixing to obtain high-strength granite concrete.

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