Mechanism sand self-compacting concrete and preparation method thereof

Abstract

The application discloses a machine-made sand self-compacting concrete and a preparation method thereof, and relates to the field of concrete, and comprises the following raw materials in parts by weight: cement 320-380 parts; machine-made sand 700-800 parts; coarse aggregate 1000-1200 parts; fly ash 60-80 parts; water 100-200 parts; water reducing agent 10-20 parts; modified aluminum slag powder 20-40 parts; epoxy resin 10-20 parts; and the modified aluminum slag powder is prepared from the following raw materials: aluminum slag powder, lithium powder, clay, silica fume and water. The application has the effect of improving the compressive strength of the concrete.

Description

Technical Field

[0001] This invention relates to the field of concrete, and in particular to a self-compacting concrete made of manufactured sand and its preparation method. Background Technology

[0002] With the rapid development of urbanization, more and more concrete is needed in urban renewal and renovation. Self-compacting concrete has low flow resistance and can flow level under its own weight. It can fill the formwork space without vibration and can form a dense and uniform structural body after hardening. It can be well combined with the needs of actual work. Self-compacting concrete is often used to improve the structural problems such as honeycomb or voids that are easy to produce in ordinary concrete. It can be well adapted to engineering structures with limited construction space, such as dense reinforcement, complex structure, thin wall, and steel pipe concrete.

[0003] Meanwhile, in the process of concrete preparation, natural sand is usually used in large quantities as fine aggregate, which leads to an increasing demand for natural sand. As a non-renewable resource, the large-scale mining of natural sand has led to a decrease in its reserves. In the long run, it cannot meet the needs of the rapidly developing construction industry. Therefore, manufactured sand is used to replace natural sand as fine aggregate in concrete.

[0004] However, manufactured sand refers to artificial sand processed by sand making machines and other auxiliary equipment. Manufactured sand has irregular shapes, poor particle roundness, and high surface roughness. Concrete made with manufactured sand usually has poor density, resulting in poor concrete strength. Summary of the Invention

[0005] To improve the compressive strength of concrete, this application provides a self-compacting concrete made of manufactured sand and its preparation method.

[0006] Firstly, the self-compacting concrete made from manufactured sand provided in this application adopts the following technical solution:

[0007] A self-compacting concrete made of manufactured sand comprises the following raw materials in parts by weight: 320-380 parts cement; 700-800 parts manufactured sand; 1000-1200 parts coarse aggregate; 60-80 parts fly ash; 100-200 parts water; 10-20 parts water-reducing agent; 20-40 parts modified aluminum slag powder; and 10-20 parts epoxy resin. The modified aluminum slag powder is prepared by modifying the following raw materials: aluminum slag powder, lithium powder, clay, silica fume, and water.

[0008] By adopting the above technical solution, this application uses manufactured sand instead of natural sand as fine aggregate to prepare concrete. The surface roughness of manufactured sand is higher, and its adhesion is stronger, which is more conducive to bonding and interlocking with cement mortar, thereby improving the compressive strength of concrete. The presence of quartz sand in manufactured sand can effectively reduce the water seepage and loss of concrete, thereby improving the strength of concrete. Compared with natural sand, manufactured sand has better fluidity and plasticity, and can effectively fill the voids in concrete, improving the density and uniformity of concrete. At the same time, this application adds modified aluminum slag powder and epoxy resin, which work together with manufactured sand to make it easier for manufactured sand to bond with cement. Manufactured sand is easier to compact than natural sand and gravel, and its production cost is lower than that of river sand. Using manufactured sand can better replace river sand as fine aggregate to prepare concrete. After modification, aluminum slag powder and silica fume have good activity. When mixed, they can fully contact and react with the concrete mixture, thereby improving the density and compressive strength of concrete.

[0009] Preferably, the modified aluminum slag powder is prepared by mixing 60-80 parts by weight of aluminum slag powder, 10-20 parts by weight of lithium powder, 10-20 parts by weight of clay, 5-15 parts by weight of silica fume and 5-10 parts by weight of water evenly, pressing them into a blank, drying and sintering; grinding them into powder, then adding 5-15 parts by weight of xanthan gum, stirring and drying to obtain the modified aluminum slag powder.

[0010] By adopting the above technical solution, this application modifies aluminum slag powder. Silica fume contains silica, which can effectively improve the compressive strength of concrete. Lithium powder is added to the aluminum slag powder. The aluminum slag powder and lithium powder are mixed with clay. During the hydration reaction, the lithium powder can be dispersed in the concrete mixture and fill the voids in the concrete mixture as a filler, making the concrete more compact. At the same time, the lithium powder reacts during the hydration reaction and can produce additional hydration products, which is beneficial to improving the compressive strength of concrete.

[0011] Preferably, the weight ratio of the aluminum slag powder, lithium powder and xanthan gum is (4.8-5):1:(0.45-0.54).

[0012] By adopting the above technical solution, when aluminum slag powder, lithium powder and xanthan gum are in a specific weight ratio, xanthan gum can coat the aluminum slag powder and lithium powder after mixing, so that the surface of the modified aluminum slag powder has good bonding properties, which helps to connect coarse aggregate and manufactured sand more tightly in concrete mixture, thereby improving the compressive strength and compactness of concrete.

[0013] Preferably, the epoxy resin is a modified epoxy resin, and the preparation method of the modified epoxy resin is as follows: 10-20 parts by weight of bamboo fiber and 2-6 parts by weight of coupling agent are mixed and stirred, washed and dried, and then mixed with 5-10 parts by weight of curing agent and 1-2 parts by weight of dimethylimidazole, heated and stirred, and then 20-40 parts by weight of epoxy resin are added and stirred evenly. After curing, the modified epoxy resin is obtained.

[0014] By adopting the above technical solution, this application modifies epoxy resin, which has a large number of hydroxyl groups, making it easy to crosslink tightly with the products of hydration reaction to form a dense network structure, thereby improving the self-compacting performance of concrete. At the same time, it can fill the pores and cracks in concrete, improving the compressive strength of concrete. By modifying epoxy resin with bamboo fiber, coupling agent is grafted onto the surface of bamboo fiber. The coupling agent provides bonding force between bamboo fiber and epoxy resin, making bamboo fiber and epoxy resin tightly bonded. The modified epoxy resin can tightly bond the manufactured sand and coarse aggregate in concrete mixture, improving the compactness of concrete.

[0015] Preferably, the weight ratio of bamboo fiber, epoxy resin and dimethylimidazole is (0.53-0.6):1:(0.04-0.05).

[0016] By adopting the above technical solution, the coupling agent improves the interfacial strength between bamboo fiber and epoxy resin. When bamboo fiber, epoxy resin and dimethylimidazole are in a specific weight ratio, the chemical bonding between bamboo fiber and epoxy resin becomes larger and larger, improving the bonding force between the two. Dimethylimidazole makes epoxy resin cure faster, improves the bonding performance of the modified epoxy resin, and makes it easier to bond with concrete mixture, thereby helping to improve the compressive strength of concrete.

[0017] Preferably, the weight ratio of the manufactured sand, modified aluminum slag powder and epoxy resin is (25.3-26):1:(0.4-0.5).

[0018] By adopting the above technical solution, when manufactured sand, modified aluminum slag powder and modified epoxy resin are in a specific weight ratio, the flowability of concrete can be improved, the drying shrinkage of concrete can be effectively reduced, and the compressive strength of concrete can be increased.

[0019] Preferably, the water-reducing agent is a polycarboxylate water-reducing agent, and the epoxy resin is a bisphenol A type epoxy resin.

[0020] By adopting the above technical solutions and selecting appropriate water-reducing agents and epoxy resins, it is helpful to improve the compressive strength of concrete.

[0021] Preferably, the particle size range of the manufactured sand is 0.5-1 mm.

[0022] By adopting the above technical solution and selecting manufactured sand within the above particle size range, the particle size range of manufactured sand is smaller, and the manufactured sand is more easily and evenly distributed in the concrete components, thereby giving the concrete good compactness.

[0023] Secondly, this application provides a method for preparing self-compacting concrete using manufactured sand, comprising the following steps: mixing cement, fly ash, coarse aggregate, manufactured sand and water evenly, then adding modified aluminum slag powder and epoxy resin and continuing to mix to obtain self-compacting concrete.

[0024] By adopting the above technical solution and method, adding modified aluminum slag powder and epoxy resin to concrete and mixing it with manufactured sand can produce concrete with high density.

[0025] In summary, this application has the following beneficial technologies:

[0026] 1. This application uses manufactured sand instead of natural sand as fine aggregate to prepare concrete. Manufactured sand has a higher surface roughness and stronger adhesion, which is more conducive to bonding and interlocking with cement mortar, thereby improving the compressive strength of concrete. Manufactured sand contains quartz sand, which can effectively reduce the water seepage and loss of concrete, thus improving the strength of concrete. Compared with natural sand, manufactured sand has better fluidity and plasticity, and can effectively fill the voids in concrete, improving the density and uniformity of concrete. At the same time, this application adds modified aluminum slag powder and epoxy resin, which work together with manufactured sand to make it easier for manufactured sand to bond with cement. Manufactured sand is easier to compact than natural sand and gravel, and its production cost is also lower than that of river sand. Using manufactured sand can better replace river sand as fine aggregate to prepare concrete. After modification, aluminum slag powder and silica fume have good activity. When mixed, they can fully contact and react with the concrete mixture, thereby improving the density and compressive strength of concrete.

[0027] 2. This application modifies aluminum slag powder. Silica fume contains silica, which can effectively improve the compressive strength of concrete. Lithium powder is added to the aluminum slag powder. The aluminum slag powder and lithium powder are mixed with clay. During the hydration reaction, the lithium powder can be dispersed in the concrete mixture and fill the voids in the concrete mixture as a filler, making the concrete more compact. At the same time, the lithium powder reacts during the hydration reaction and can produce additional hydration products, which is beneficial to improving the compressive strength of concrete.

[0028] 3. This application modifies epoxy resin, which has a large number of hydroxyl groups, making it easy to crosslink tightly with the products of hydration reaction to form a dense network structure, thereby improving the self-compacting properties of concrete. Simultaneously, it can fill pores and cracks in concrete, increasing its compressive strength. Furthermore, by modifying epoxy resin with bamboo fiber, a coupling agent is grafted onto the surface of the bamboo fiber. The coupling agent provides adhesion between the bamboo fiber and the epoxy resin, ensuring a tight bond between them. The modified epoxy resin can then tightly bind the manufactured sand and coarse aggregate in the concrete mixture, improving the compactness of the concrete. Detailed Implementation

[0029] The present application will be further described in detail below with reference to embodiments and comparative examples.

[0030] Preparation Example

[0031] Preparation Example 1

[0032] A method for preparing modified epoxy resin: 10 kg of bamboo fiber and 2 kg of KH550 silane coupling agent are mixed and stirred at 60°C for 10 min. After washing with ethanol, the mixture is dried at 100°C for 2 h. Then, it is mixed with 5 kg of methyltetrahydrophthalic anhydride curing agent and 1 kg of dimethylimidazole, heated to 80°C and stirred for 10 min. Then, 20 kg of epoxy resin is added and stirred evenly at 60 rad / min for 30 min. Finally, the mixture is cured at 120°C for 3 h to obtain the modified epoxy resin.

[0033] Preparation Example 2

[0034] A method for preparing modified epoxy resin: 20 kg of bamboo fiber and 6 kg of KH550 silane coupling agent are mixed and stirred at 60°C for 10 min. After washing with ethanol, the mixture is dried at 100°C for 2 h. Then, it is mixed with 10 kg of methyltetrahydrophthalic anhydride curing agent and 2 kg of dimethylimidazole, heated to 80°C and stirred for 10 min. Then, 40 kg of epoxy resin is added and stirred evenly at 60 rad / min for 30 min. Finally, the mixture is cured at 120°C for 3 h to obtain the modified epoxy resin.

[0035] Preparation Example 3

[0036] A method for preparing a modified epoxy resin differs from Preparation Example 2 in that the amount of bamboo fiber added is 16 kg, the amount of epoxy resin added is 30 kg, and the amount of dimethylimidazole added is 1.2 kg.

[0037] Preparation Example 4

[0038] A method for preparing a modified epoxy resin differs from Preparation Example 2 in that the amount of bamboo fiber added is 18 kg, the amount of epoxy resin added is 30 kg, and the amount of dimethylimidazole added is 1.5 kg.

[0039] Example

[0040] Example 1

[0041] A method for preparing self-compacting concrete using manufactured sand: 32 kg of cement, 6 kg of fly ash, 100 kg of coarse aggregate, 70 kg of manufactured sand and 10 kg of water are put into a mixing tank and stirred for 30 seconds at a temperature of 60℃ and a rotation speed of 60 r / min. Then, 2 kg of modified aluminum slag powder and 1 kg of epoxy resin are added and stirred for another 1 minute to obtain self-compacting concrete.

[0042] The manufactured sand has a particle size of 1 mm, the water-reducing agent is a polycarboxylate water-reducing agent with a fineness of 3% and a water reduction rate of 25%; the epoxy resin is bisphenol A type epoxy resin with a viscosity of 12000 mPas.

[0043] The modified aluminum slag powder is prepared as follows: 60 kg of aluminum slag powder, 10 kg of lithium powder, 10 kg of clay, 5 kg of silica fume and 5 kg of water are mixed evenly and pressed into a blank. The blank is dried in an oven at 100°C for 6 hours. After drying, it is placed in a muffle furnace and sintered at 1400°C for 6 hours. After sintering, the blank is ground into powder with a particle size of 2 mm. Then, 5 kg of xanthan gum is added and heated and stirred at 90°C for 6 hours to obtain the modified aluminum slag powder.

[0044] Example 2

[0045] A method for preparing self-compacting concrete using manufactured sand: 38 kg of cement, 8 kg of fly ash, 120 kg of coarse aggregate, 80 kg of manufactured sand and 20 kg of water are put into a mixing tank and stirred for 30 seconds at a temperature of 60℃ and a rotation speed of 60 r / min. Then, 4 kg of modified aluminum slag powder and 2 kg of epoxy resin are added and stirred for another 1 minute to obtain self-compacting concrete.

[0046] The manufactured sand has a particle size of 1 mm, the water-reducing agent is a polycarboxylate water-reducing agent with a fineness of 3% and a water reduction rate of 25%; the epoxy resin is bisphenol A type epoxy resin with a viscosity of 12000 mPas.

[0047] The modified aluminum slag powder is prepared as follows: 60 kg of aluminum slag powder, 10 kg of lithium powder, 10 kg of clay, 5 kg of silica fume and 5 kg of water are mixed evenly and pressed into a blank. The blank is dried in an oven at 100°C for 6 hours. After drying, it is placed in a muffle furnace and sintered at 1400°C for 6 hours. After sintering, the blank is ground into powder with a particle size of 2 mm. Then, 5 kg of xanthan gum is added and heated and stirred at 90°C for 6 hours to obtain the modified aluminum slag powder.

[0048] Example 3

[0049] A method for preparing self-compacting concrete using manufactured sand: 36 kg of cement, 7 kg of fly ash, 110 kg of coarse aggregate, 75 kg of manufactured sand and 15 kg of water are put into a mixing tank and stirred for 30 seconds at a temperature of 60℃ and a rotation speed of 60 r / min. Then, 3 kg of modified aluminum slag powder and 1.5 kg of epoxy resin are added and the mixture is stirred for another 1 minute to obtain self-compacting concrete.

[0050] The manufactured sand has a particle size of 1 mm, the water-reducing agent is a polycarboxylate water-reducing agent with a fineness of 3% and a water reduction rate of 25%; the epoxy resin is bisphenol A type epoxy resin with a viscosity of 12000 mPas.

[0051] The modified aluminum slag powder is prepared as follows: 60 kg of aluminum slag powder, 10 kg of lithium powder, 10 kg of clay, 5 kg of silica fume and 5 kg of water are mixed evenly and pressed into a blank. The blank is dried in an oven at 100°C for 6 hours. After drying, it is placed in a muffle furnace and sintered at 1400°C for 6 hours. After sintering, the blank is ground into powder with a particle size of 2 mm. Then, 5 kg of xanthan gum is added and heated and stirred at 90°C for 6 hours to obtain the modified aluminum slag powder.

[0052] Example 4

[0053] A method for preparing self-compacting concrete using manufactured sand differs from Example 3 in that the modified aluminum slag powder is prepared as follows: 80 kg of aluminum slag powder, 20 kg of lithium powder, 20 kg of clay, 15 kg of silica fume, and 10 kg of water are mixed evenly and pressed into a green body. The green body is then dried in an oven at 100°C for 6 hours and then sintered in a muffle furnace at 1400°C for 6 hours. After sintering, the green body is ground into powder with a particle size of 2 mm. Then, 10 kg of xanthan gum is added and the mixture is heated and stirred at 90°C for 6 hours to obtain the modified aluminum slag powder.

[0054] Example 5

[0055] A method for preparing self-compacting concrete using manufactured sand differs from Example 3 in that the amount of aluminum slag powder added is 72 kg, the amount of lithium powder added is 15 kg, and the amount of xanthan gum added is 7 kg.

[0056] Example 6

[0057] A method for preparing self-compacting concrete using manufactured sand differs from Example 3 in that the amount of aluminum slag powder added is 75 kg, the amount of lithium powder added is 15 kg, and the amount of xanthan gum added is 8 kg.

[0058] Example 7

[0059] A method for preparing self-compacting concrete using manufactured sand, which differs from Example 6 in that the epoxy resin is replaced in an equal amount with the modified epoxy resin prepared in Preparation Example 1.

[0060] Example 8

[0061] A method for preparing self-compacting concrete using manufactured sand, which differs from Example 6 in that the epoxy resin is replaced in an equal amount with the modified epoxy resin obtained in Preparation Example 2.

[0062] Example 9

[0063] A method for preparing self-compacting concrete using manufactured sand, which differs from Example 6 in that the epoxy resin is replaced in an equal amount with the modified epoxy resin prepared in Example 3.

[0064] Example 10

[0065] A method for preparing self-compacting concrete using manufactured sand, which differs from Example 6 in that the epoxy resin is replaced in an equal amount with the modified epoxy resin obtained in Preparation Example 4.

[0066] Example 11

[0067] A method for preparing self-compacting concrete using manufactured sand differs from Example 6 in that, in the raw material for modifying epoxy resin in Preparation Example 4, bamboo fiber is replaced in an equal amount with basalt fiber.

[0068] Example 12

[0069] A method for preparing self-compacting concrete using manufactured sand differs from Example 10 in that the amount of manufactured sand used is 76 kg, the amount of modified aluminum slag powder used is 3 kg, and the amount of modified epoxy resin used in Preparation Example 4 is 1.2 kg.

[0070] Example 13

[0071] A method for preparing self-compacting concrete using manufactured sand differs from Example 10 in that the amount of manufactured sand used is 78 kg, the amount of modified aluminum slag powder used is 3 kg, and the amount of modified epoxy resin used in Preparation Example 4 is 1.5 kg.

[0072] Comparative Example

[0073] Comparative Example 1

[0074] A method for preparing self-compacting concrete using manufactured sand, which differs from Example 1 in that modified aluminum slag powder is replaced with aluminum slag powder in equal amounts.

[0075] Comparative Example 2

[0076] A method for preparing self-compacting concrete using manufactured sand, which differs from Example 1 in that modified aluminum slag powder is replaced with lithium powder in equal amounts.

[0077] Comparative Example 3

[0078] A method for preparing self-compacting concrete using manufactured sand, which differs from Example 1 in that epoxy resin is replaced with an equal amount of polyurethane.

[0079] Comparative Example 4

[0080] A method for preparing self-compacting concrete using manufactured sand, which differs from Example 1 in that epoxy resin is not added.

[0081] Comparative Example 5

[0082] A method for preparing self-compacting concrete using manufactured sand, which differs from Example 1 in that aluminum slag powder is not added.

[0083] Performance testing:

[0084] Compressive strength test: In accordance with the provisions of GB / T 50081-2002 "Standard for Test Methods of Mechanical Properties of Ordinary Concrete", the compressive strength of concrete prepared in Examples 1-13 and Comparative Examples 1-5 after standard curing for 7 days and 28 days was tested.

[0085] Slump flow test: The slump flow of the self-compacting concrete prepared in Examples 1-13 and Comparative Examples 1-5 was tested according to JGJ / T 283—2012 Technical Specification for Application of Self-Compacting Concrete.

[0086]

[0087] Based on the data comparison of Examples 1-3 and Comparative Examples 1-5, it can be seen that this application uses manufactured sand instead of natural sand as fine aggregate to prepare concrete. The surface roughness of manufactured sand is higher, and the adhesion is stronger, which is more conducive to bonding and interlocking with cement mortar, thereby improving the compressive strength of concrete. The presence of quartz sand in manufactured sand can effectively reduce the water seepage and loss of concrete, thereby improving the strength of concrete. Compared with natural sand, manufactured sand has better fluidity and plasticity, and can effectively fill the voids in concrete, improving the density and uniformity of concrete. At the same time, this application adds modified aluminum slag powder and epoxy resin, which work together with manufactured sand to make it easier for manufactured sand to bond with cement. Manufactured sand is easier to compact than natural sand and gravel, and its production cost is lower than that of river sand. Using manufactured sand can better replace river sand as fine aggregate to prepare concrete. After modification, aluminum slag powder and silica fume have good activity. After mixing, they can fully contact and react with the concrete mixture, thereby improving the density and compressive strength of concrete.

[0088] Based on the data comparison of Examples 3-6, it can be seen that the modified aluminum slag powder in this application contains silica, which can effectively improve the compressive strength of concrete. Lithium powder is added to the aluminum slag powder. The aluminum slag powder and lithium powder are mixed with clay. During the hydration reaction, the lithium powder can be dispersed in the concrete mixture and fill the voids in the concrete mixture as a filler, making the concrete more compact. At the same time, the lithium powder reacts in the hydration reaction and can produce additional hydration products, which is beneficial to improving the compressive strength of concrete.

[0089] According to the data comparison of Examples 6-11, since the coupling agent improves the interfacial strength between bamboo fiber and epoxy resin, when bamboo fiber, epoxy resin and dimethylimidazole are in a specific weight ratio, the chemical bonding between bamboo fiber and epoxy resin becomes larger and larger, improving the bonding force between the two. Dimethylimidazole makes epoxy resin cure faster, improves the bonding performance of the modified epoxy resin, and makes it easier to bond with concrete mixture, thereby helping to improve the compressive strength of concrete.

[0090] A comparison of the data from Examples 10 and 12-13 shows that when manufactured sand, modified aluminum slag powder, and modified epoxy resin are in a specific weight ratio, the flowability of concrete can be improved, the drying shrinkage of concrete can be effectively reduced, and the compressive strength of concrete can be increased.

[0091] The specific embodiments are merely explanations of this application and are not intended to limit it. After reading this specification, those skilled in the art can make modifications to these embodiments without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. A self-compacting concrete made of manufactured sand, characterized in that: The raw materials include the following parts by weight: cement 320-380 parts; manufactured sand 700-800 parts; coarse aggregate 1000-1200 parts; 60-80 parts fly ash; 100-200 parts water; 10-20 parts of water-reducing agent; 20-40 parts modified aluminum slag powder; 10-20 parts epoxy resin; the modified aluminum slag powder is prepared by modifying the following raw materials: aluminum slag powder, lithium powder, clay, silica fume and water; The modified aluminum slag powder is prepared by mixing 60-80 parts by weight of aluminum slag powder, 10-20 parts by weight of lithium powder, 10-20 parts by weight of clay, 5-15 parts by weight of silica fume and 5-10 parts by weight of water evenly, pressing it into a blank, drying and sintering; grinding it into powder, then adding 5-15 parts by weight of xanthan gum, stirring and drying to obtain the modified aluminum slag powder; and the weight ratio of aluminum slag powder, lithium powder and xanthan gum is (4.8-5):1:(0.45-0.54). The epoxy resin is a modified epoxy resin. The preparation method of the modified epoxy resin is as follows: 10-20 parts by weight of bamboo fiber and 2-6 parts by weight of coupling agent are mixed and stirred, washed and dried, and then mixed with 5-10 parts by weight of curing agent and 1-2 parts by weight of dimethylimidazole, heated and stirred, and then 20-40 parts by weight of epoxy resin are added and stirred evenly. After curing, the modified epoxy resin is obtained.

2. The self-compacting concrete made of manufactured sand according to claim 1, characterized in that: The weight ratio of bamboo fiber, epoxy resin and dimethylimidazole is (0.53-0.6):1:(0.04-0.05).

3. The self-compacting concrete made of manufactured sand according to claim 1, characterized in that: The weight ratio of the manufactured sand, modified aluminum slag powder and epoxy resin is (25.3-26):1:(0.4-0.5).

4. The self-compacting concrete made of manufactured sand according to claim 1, characterized in that: The water-reducing agent used is a polycarboxylate water-reducing agent.

5. The self-compacting concrete made of manufactured sand according to claim 1, characterized in that: The epoxy resin used is bisphenol A type epoxy resin.

6. The self-compacting concrete made of manufactured sand according to claim 1, characterized in that: The particle size range of the manufactured sand is 0.5-1mm.

7. A method for preparing self-compacting concrete using manufactured sand, characterized in that: The method for preparing the self-compacting concrete according to any one of claims 1-6 includes the following steps: mixing cement, fly ash, coarse aggregate, manufactured sand and water evenly, then adding modified aluminum slag powder and epoxy resin and continuing to mix to obtain self-compacting concrete.

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