High-performance sprayed concrete material for single-layer lining and preparation method of high-performance sprayed concrete material

Abstract

The invention relates to the technical field of concrete preparation, in particular to a high-performance sprayed concrete material for single-layer lining and a preparation method thereof.The high-performance sprayed concrete material is prepared from, by weight, 380-410 kg / m < 3 > of cement, 160-180 kg / m < 3 > of water, 800-900 kg / m < 3 > of coarse aggregate, 900-1000 kg / m < 3 > of fine aggregate, 30-40 kg / m < 3 > of silicon powder, 6-10 kg / m < 3 > of water reducer, 25-30 kg / m < 3 > of accelerator and 6-10 kg / m < 3 > of antifreeze agent. The antifreeze agent is composed of a photo-thermal conversion material, calcium nitrate and barium oxide according to the mass ratio of 1: (3-5): (1.5-3). The sprayed concrete material prepared by the invention can maintain high compressive strength and high impermeability in a low-temperature environment in winter, has excellent freeze-thaw resistance, and solves the problem that sprayed concrete is not easy to construct at negative temperature.

Description

Technical Field

[0001] The present invention relates to the technical field of concrete preparation, and particularly relates to a high-performance shotcrete material for single-layer lining and a preparation method thereof. Background Art

[0002] Shotcrete is a kind of concrete formed by sending a concrete mixture prepared by mixing cementitious materials, aggregates, admixtures, etc. in a certain proportion to a shotcrete machine, and then conveying it to the shotcrete nozzle by means of compressed air or other methods and spraying it at a high speed onto the sprayed surface. Shotcrete has the advantages of convenient construction, short construction period, high early strength, and self-compacting without vibration, and is widely used in tunnel engineering. Single-layer lining is a layer of support structure directly constructed on the surface of the surrounding rock after tunnel excavation, abandoning the layered structure. Its main material is high-performance shotcrete, which has the advantages of short construction period and low cost compared with the composite lining.

[0003] The existing shotcrete is mainly used for composite lining. For the shotcrete used in single-layer lining, it is required to have good workability, high strength, excellent durability, especially high water penetration resistance and other requirements. Due to the problems of insufficient impermeability, high shrinkage rate, and poor toughness of traditional shotcrete, it is difficult to meet the strict requirements of single-layer lining structure for durability, crack resistance, and bearing capacity. After spraying, the compactness is relatively low, and the design value of the strength grade is relatively low. Directly used in single-layer lining, it is easy to appear cracks, water seepage and other phenomena.

[0004] To meet the working requirements of single-layer linings, various high-performance shotcretes have emerged. For example, the invention patent with the application number CN202111597309.X discloses a gradient shotcrete structure for tunnel single-layer lining and its construction method, which includes 980-1020 parts of cement, 1804-1916 parts of medium sand, 1203-1277 parts of crushed stone, 16.8-17.2 parts of polycarboxylate superplasticizer, 9.9-10.1 parts of silica fume agent, 11.9-12.1 parts of polyolefin fiber, 396-404 parts of water, and 79.2-80.8 parts of non-alkali accelerating agent. This high-performance shotcrete is a permanent lining with a service life of 100 years, and at the same time, the secondary lining is cancelled, making the construction simple. Another example is the invention patent with the application number CN201910095853.0, which discloses a material and preparation method for a waterproof single-layer lining in hard rock tunnels. It consists of three layers of shotcrete or mortar materials in a gradient manner, and uses a composite steel fiber shotcrete layer material by compounding cementitious materials, hybrid fibers, liquid early-strength agents, liquid non-alkali accelerating agents, etc. Among them, the solute components of the liquid early-strength agent are a composition of early-strength polycarboxylate water reducer, calcium lignosulfonate or calcium lignohumate, and inorganic calcium salts. Through the three-layer design of hybrid steel fiber shotcrete, water-retaining shotcrete mortar, and low-shrinkage shotcrete, finally, a single-layer lining gradient concrete with a compressive strength greater than 15.0 MPa at 8 h, a compressive strength greater than 45.0 MPa at 28 d, a flexural strength greater than 5.5 MPa at 28 d, a drying shrinkage rate less than 200 microstrain at 28 d, an interfacial bond strength greater than 1.5 MPa, and no water seepage phenomenon under a constant water seepage pressure of 1.2 MPa for 30 d is produced.

[0005] However, under the severe cold conditions in winter, the single-layer lining is prone to internal expansion cracks in the concrete structure under repeated freeze-thaw cycles, which affects the service life of the single-layer lining. At the same time, in a low-temperature environment, shotcrete is also not easy to construct. In response to this, the invention patent with the application number CN202211629123.2 discloses an anti-freeze and early-strength shotcrete for high-altitude and cold regions and its usage method. By adding a liquid composite anti-freeze component to the concrete to improve its anti-freeze performance, where the liquid composite anti-freeze component consists of any one of sodium thiocyanate, potassium thiocyanate, calcium nitrite, and urea, alcohol aluminum, alkanolamine, and water. The liquid composite anti-freeze component is used to lower the freezing point of the free water in the concrete in the alpine environment and relieve the frost heaving stress generated by the freezing of water. However, sodium thiocyanate and potassium thiocyanate are highly toxic, prone to deliquescence in the air, and release toxic gases when encountering acids, which not only pollutes the environment but also poses certain safety hazards during long-term use and causes health problems for construction workers. To improve the safety of using shotcrete materials, it is necessary to propose a new type of high-performance shotcrete material for single-layer lining that is anti-freeze, environmentally friendly, and harmless. Summary of the Invention

[0006] In view of this, the object of the present invention is to provide a high-performance shotcrete material for single-layer lining and its preparation method, aiming to solve the problem that the existing shotcrete has insufficient performance in the low-temperature environment in winter, thus being limited in application in single-layer lining.

[0007] Based on the above object, the present invention provides a high-performance shotcrete material for single-layer lining. By weight ratio, it includes the following raw materials: 380 - 410 kg / m of cement 3 、160 - 180 kg / m of water 3 、800 - 900 kg / m of coarse aggregate 3 、900 - 1000 kg / m of fine aggregate 3 、30 - 40 kg / m of silica fume 3 、6 - 10 kg / m of water reducer 3 、25 - 30 kg / m of accelerating agent 3 、6 - 10 kg / m of antifreeze 3 ;

[0008] The antifreeze is composed of a photothermal conversion material, calcium nitrate, and barium oxide in a mass ratio of 1:(3 - 5):(1.5 - 3).

[0009] Further, the cement is ordinary Portland cement with a strength grade of 42.5, an initial setting time of 50 min, and a final setting time of 200 min.

[0010] Further, the coarse aggregate is continuously graded limestone gravel with a maximum particle size of 10 mm.

[0011] Further, the fine aggregate is continuously graded manufactured sand with a fineness modulus of 2.5 - 3.

[0012] Further, the silica fume has a specific surface area ≥ 20000 m 2 / kg and a silica dioxide content ≥ 90%.

[0013] Further, the water reducer is one or more of polycarboxylate superplasticizer and naphthalene superplasticizer.

[0014] Further, the accelerating agent is nanocrystalline colloid polymer, purchased from Tianjin Rumi New Materials Co., Ltd.

[0015] Further, the photothermal conversion material is azobenzene-grafted graphene, and its preparation method is: adding graphene oxide into absolute ethanol, stirring and dispersing, then adding 4-(4-aminophenylazo)benzenesulfonic acid and dicyclohexylcarbodiimide, stirring and reacting at 70 - 75 °C for 3 - 5 h, centrifuging, washing, and drying to obtain azobenzene-grafted graphene.

[0016] Further, the mass ratio of graphene oxide, absolute ethanol, 4 - sulfonic acid - 4 - aminoazobenzene, and dicyclohexylcarbodiimide is 1:10:(0.2 - 0.3):(0.03 - 0.05).

[0017] The present invention also provides a preparation method of a high - performance shotcrete material for single - layer lining, comprising the following steps:

[0018] S1: Mix cement, water, coarse aggregate, fine aggregate, silica fume, and water - reducing agent evenly to obtain a mixture;

[0019] S2: Add a setting accelerator and an antifreeze agent to the mixture and stir evenly to obtain the high - performance shotcrete material.

[0020] Advantages of the present invention:

[0021] For the first time, the present invention uses a photothermal conversion material, a composite antifreeze agent of calcium nitrate and barium oxide and applies it to the shotcrete material, which has multi - dimensional synergistic antifreeze effects, improves early strength, reduces the rebound rate, and has durability, etc. Moreover, it is environmentally friendly and does not release toxic and harmful components.

[0022] The present invention utilizes the chemical reaction between - NH2 in 4 - sulfonic acid - 4 - aminoazobenzene and - COOH and epoxy groups on the surface of graphene oxide to covalently graft 4 - sulfonic acid - 4 - aminoazobenzene onto the surface of graphene oxide, forming a photothermal conversion material. The light energy stored and accumulated by it is converted into heat energy and released, synergistically antifreezing with calcium nitrate and barium oxide, improving the low - temperature construction performance of the shotcrete material and the anti - freeze - cracking performance of the produced single - layer lining. At the same time, azobenzene - grafted graphene also has sulfonic acid groups, which can coordinate with calcium ions and barium ions to form azobenzene - grafted graphene - metal complexes, further optimizing the internal microstructure of the concrete and improving its compactness and strength.

[0023] The shotcrete material prepared by the present invention can also maintain a high level of comprehensive performance in a low - temperature environment in winter, has high compressive strength and strong impermeability performance, and has excellent freeze - thaw resistance performance, solving the problem that shotcrete is not easy to construct at negative temperatures. Description of the Drawings

[0024] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings described below are only for the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0025] Figure 1 It is a sample diagram of transporting concrete materials by a concrete mixer truck in Example 2 of the present invention;

[0026] Figure 2 This is the sample diagram of the spraying process of the concrete material by the wet spraying machine in Embodiment 2 of the present invention. Detailed implementation manners

[0027] To make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below with reference to specific embodiments.

[0028] The present invention provides a high-performance sprayed concrete material for single-layer lining. By weight ratio, it includes the following raw materials: cement 380 - 410 kg / m 3 、water 160 - 180 kg / m 3 、coarse aggregate 800 - 900 kg / m 3 、fine aggregate 900 - 1000 kg / m 3 、silica fume 30 - 40 kg / m 3 、water reducing agent 6 - 10 kg / m 3 、accelerator 25 - 30 kg / m 3 、anti-freezing agent 6 - 10 kg / m 3 ;

[0029] The anti-freezing agent is composed of a photothermal conversion material, calcium nitrate, and barium oxide in a mass ratio of 1:(3 - 5):(1.5 - 3). This embodiment uses a photothermal conversion material, calcium nitrate, and barium oxide to prepare an anti-freezing agent and apply it to the sprayed concrete material, which has multi-dimensional synergistic anti-freezing effects, improves early strength, reduces the rebound rate, and has durability. The specific analysis is as follows:

[0030] 1. Multi-dimensional anti-freezing mechanism: Physical and chemical synergistic effect

[0031] Active temperature rise effect of the photothermal material:

[0032] The photothermal conversion material can absorb the energy of sunlight or artificial light sources and convert it into heat energy to directly increase the internal temperature of the concrete. This active heat generation characteristic can significantly offset the inhibitory effect of low-temperature environments on the hydration of concrete. Especially in tunnels and underground projects with large day-night temperature differences or insufficient light, it can maintain the appropriate temperature of the concrete and prevent freeze-thaw damage.

[0033] Freezing point depression and early strength enhancement of calcium nitrate:

[0034] As a traditional anti-freezing agent, calcium nitrate inhibits ice crystal formation by lowering the freezing point of pore water (down to below -15 °C at the lowest); at the same time, its Ca 2+ and NO3 - ions can accelerate the hydration reaction of cement minerals, shorten the setting time, improve early strength, and reduce the risk of plastic freezing damage of concrete at low temperatures.

[0035] Synergistic strengthening of barium oxide:

[0036] Barium oxide (BaO) reacts with water to form barium hydroxide and release heat (exothermic reaction), further assisting in temperature rise. At the same time, the formed barium hydroxide can react with silicon oxide in silicon powder to form a denser hydrated barium silicate product, filling pores, reducing the water migration path, and enhancing the impermeability. In addition, barium salts have a certain inhibitory effect on sulfate attack, which can improve the durability of concrete.

[0037] Synergistic advantage: The combination of the three forms a multiple anti-freezing mechanism of "active heat generation + freezing point inhibition + microstructure optimization", significantly improving the freeze-thaw cycle resistance of shotcrete at low temperatures and reducing microcracks and structural damage caused by freezing.

[0038] 2. Accelerating the hydration process and strength development

[0039] Thermal activation and ionic catalysis:

[0040] The exothermic reaction of the photothermal conversion material and barium oxide provides continuous heat, accelerating the hydration reaction rate of tricalcium silicate (C3S) and dicalcium silicate (C2S). And NO3 of calcium nitrate - As a strong oxidant, it can promote the dissolution of aluminate phase and shorten the induction period. This thermo-chemical coupling effect enables the shotcrete to still quickly set and harden at low temperatures, meeting the requirements for early strength of single-layer lining.

[0041] Microstructure optimization:

[0042] The introduction of calcium nitrate and barium oxide can optimize the distribution of hydration products, reduce the loose structure caused by delayed hydration at low temperatures, promote the formation of more uniform and denser C-S-H gel and ettringite, and improve the compactness and later strength of concrete.

[0043] 3. Improving the construction performance of shotcrete

[0044] Reducing the rebound rate and enhancing the bonding strength:

[0045] The photothermal conversion material can also be used as a thickening agent to improve the cohesion of the concrete mixture and reduce the rebound loss during spraying; the early strength characteristic of calcium nitrate enhances the bonding strength between the concrete and the base surface, especially suitable for the wet spraying process;

[0046] Regulating the pumpability and fluidity:

[0047] The photothermal conversion material and calcium nitrate can synergistically improve the rheology of the slurry, ensuring the continuity and uniformity of the spraying process;

[0048] 4. Environmental adaptability and durability improvement

[0049] Wide temperature range applicability:

[0050] The antifreeze can still convert the stored light energy into heat energy through photothermal conversion and release it at extremely low temperatures below -30°C, maintaining the internal temperature of the concrete and avoiding the limitations of traditional antifreezes that only rely on reducing the freezing point.

[0051] Freeze-thaw and salt erosion resistance:

[0052] The introduction of the antifreeze also helps to form a dense microstructure, reduce water penetration, and combined with the sulfate solidification effect of barium salts, it can resist freeze-thaw cycles and the erosion of Cl - 、SO4 2- salts, extending the service life of the concrete.

[0053] In this embodiment, the cement is ordinary Portland cement with a strength grade of 42.5, an initial setting time of 50 min, and a final setting time of 200 min.

[0054] In this embodiment, the coarse aggregate is continuously graded limestone gravel with a maximum particle size of 10 mm.

[0055] In this embodiment, the fine aggregate is continuously graded manufactured sand with a fineness modulus of 2.5 - 3.

[0056] In this embodiment, the silica fume has a specific surface area ≥ 20000 m 2 / kg and a silica content ≥ 90%.

[0057] In this embodiment, the water reducer is one or more of polycarboxylate superplasticizer and naphthalene superplasticizer.

[0058] In this embodiment, the accelerating agent is nanocrystalline colloid polymer, purchased from Tianjin Rumi New Materials Co., Ltd.

[0059] In this embodiment, the photothermal conversion material is azobenzene-grafted graphene, and its preparation method is as follows: Graphene oxide is added to anhydrous ethanol. After stirring and dispersing, p-aminophenylazobenzene-4-sulfonic acid and dicyclohexylcarbodiimide are added, and the mixture is stirred and reacted at 70-75 °C for 3-5 h. After centrifugation, washing, and drying, azobenzene-grafted graphene is obtained. In this embodiment, by using the chemical reaction between -NH2 in p-aminophenylazobenzene-4-sulfonic acid and -COOH and epoxy groups on the surface of graphene oxide, p-aminophenylazobenzene-4-sulfonic acid is covalently grafted onto the surface of graphene oxide to form a photothermal conversion material. The light energy stored by it is converted into heat energy and released, and it cooperates with calcium nitrate and barium oxide to resist freezing, improving the low-temperature construction performance of the shotcrete material and the frost resistance cracking performance of the single-layer lining produced; at the same time, azobenzene-grafted graphene also has sulfonic acid groups, which can coordinate with calcium ions and barium ions to form azobenzene-grafted graphene-metal complexes, further optimizing the microstructure inside the concrete and improving its compactness and strength.

[0060] Example 1

[0061] A high-performance shotcrete material for single-layer lining, by weight ratio, includes the following raw materials: cement 394 kg / m 3 、water 172 kg / m 3 、coarse aggregate 844 kg / m 3 、fine aggregate 914 kg / m 3 、silica fume 36 kg / m 3 、water reducing agent 6.45 kg / m 3 、accelerator 25.8 kg / m 3 、anti-freezing agent 6.75 kg / m 3 ;

[0062] The anti-freezing agent is composed of a photothermal conversion material, calcium nitrate, and barium oxide in a mass ratio of 1:3.5:2.

[0063] The cement is ordinary Portland cement with a strength grade of 42.5, an initial setting time of 50 min, and a final setting time of 200 min.

[0064] The coarse aggregate is continuously graded limestone gravel with a particle size range of 5-10 mm.

[0065] The fine aggregate is continuously graded manufactured sand with a fineness modulus of 2.9 measured by the standard sieving method.

[0066] The silica fume has a specific surface area ≥ 20132 m 2 / kg and a silica content of 93%.

[0067] The water reducing agent is a polycarboxylate superplasticizer.

[0068] The described accelerating agent is a nanocrystalline colloid polymer, purchased from Tianjin Rumi New Materials Co., Ltd.

[0069] The described photothermal conversion material is azobenzene-grafted graphene, and its preparation method is as follows: Graphene oxide is added to anhydrous ethanol, stirred and dispersed, then 4-aminophenylazobenzenesulfonic acid and dicyclohexylcarbodiimide are added, and the mixture is stirred and reacted at 75 °C for 5 h. After centrifugation, washing, and drying, azobenzene-grafted graphene is obtained. Among them, the mass ratio of graphene oxide, anhydrous ethanol, 4-aminophenylazobenzenesulfonic acid, and dicyclohexylcarbodiimide is 1:10:0.25:0.03.

[0070] Comparative Example 1 is the same as Example 1, except that: In Comparative Example 1, calcium nitrate is used as the antifreeze agent.

[0071] Comparative Example 2 is the same as Example 1, except that: The antifreeze agent in Comparative Example 2 is composed of calcium nitrate and barium oxide in a mass ratio of 3.5:2, that is, it does not contain the photothermal conversion material.

[0072] Indoor test configuration process:

[0073] ① According to the mix ratio, calculate and weigh the raw materials required for a single pour, and weigh an appropriate amount of cement, aggregate, and water, pour them into the concrete mixer, stir for 30 s for potting, and then pour out. At the same time, clean the surface of the required 150 mm×150 mm×150 m mold, brush oil, and set aside;

[0074] ② Pour the weighed coarse and fine aggregates and silica fume into the mixer and stir for about 60 s;

[0075] ③ Slowly and evenly pour the cement into the mixing drum, start the mixer and continue to stir for about 60 s;

[0076] ④ Slowly and evenly pour the water and water reducer into the mixing drum, and stir for about 120 s; and measure the slump and spread of the concrete mixture, and the measured slump is 240 mm and the spread is 500 mm;

[0077] ⑤ Slowly and evenly pour the accelerating agent and antifreeze agent into the mixing drum, and stir for about 30 s and then pour out the mixture;

[0078] ⑥ Pour the mixture into the test mold, place it on the vibrating table and vibrate for 60 s to 120 s. After vibrating and compacting, use a plastering knife to level the surface of the specimen. Place the specimen on a flat ground and cure it naturally for 24 h, then demold it. Subsequently, place the specimen in a standard curing room at a temperature of -5 °C, a relative humidity of 95%, and a 50 W xenon lamp illumination condition for curing. When the curing age reaches the required age for the test, relevant tests can be started.

[0079] Test the compressive strength and splitting tensile strength of the shotcrete specimens in the above curing environment according to GBT 50081-2019 "Test Methods for Physical and Mechanical Properties of Concrete".

[0080] Conduct a frost resistance test according to GB / T 50082-2024 "Standard Test Methods for Long-Term Performance and Durability of Ordinary Concrete". After 300 freeze-thaw cycles, measure the strength loss rate.

[0081] The test results are shown in the following table:

[0082]

[0083] As can be seen from the above table, the comprehensive performance of the high-performance shotcrete material of the single-layer lining produced by the present invention is significantly superior to that of Comparative Documents 1-2, showing excellent frost resistance performance. Under the low-temperature curing condition of minus temperature, it can also achieve high compressive strength and high impermeability performance. Compared with Comparative Example 2 without the photothermal conversion material, the low-temperature compressive strength, impermeability grade, and frost resistance performance of Example 1 have been greatly improved. This shows that the azobenzene grafted on the graphene photothermal conversion material is of great significance for improving the low-temperature construction performance of the shotcrete material and the frost crack resistance performance of the produced single-layer lining. Analyzing the reasons, the photothermal conversion material converts the light energy stored and accumulated by it into heat energy for release, and cooperates with calcium nitrate and barium oxide to resist frost. The combination of the three forms a multiple frost resistance mechanism of "active heat generation + freezing point inhibition + microstructure optimization", significantly improving the frost resistance and thawing cycle ability of the shotcrete at low temperature, reducing microcracks and structural damage caused by freezing. At the same time, the azobenzene grafted graphene also has sulfonic acid groups, which can coordinate with calcium ions and barium ions to form azobenzene grafted graphene-metal complexes, further optimizing the internal microstructure of the concrete and improving its compactness and strength.

[0084] Example 2

[0085] Prepare the high-performance shotcrete material according to Example 1 for single-layer lining construction. See Figure 1 The sample diagram of transporting the concrete material by a concrete mixer truck and Figure 2 The spraying process sample diagram of spraying the concrete material by a wet shotcreting machine. The construction process is as follows:

[0086] ① According to the mix ratio, use the computer system of the on-site batching plant to calculate and weigh the raw materials required for a single pour, and prepare cement, water, coarse aggregate, fine aggregate, silica fume, and water reducer through the automatic control system of the batching plant and mix them;

[0087] ② Transport the concrete to the tunnel spraying site by a concrete mixer truck;

[0088] ③ Add accelerator and antifreeze in the wet shotcreting machine, and spray the concrete at high speed onto the sprayed surface.

[0089] Those of ordinary skill in the art should understand that any discussion of the above embodiments is merely exemplary and is not intended to imply that the scope of the present invention (including the claims) is limited to these examples; within the concept of the present invention, the technical features in the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of different aspects of the present invention as described above, which are not provided in detail for the sake of brevity.

[0090] The present invention is intended to cover all such substitutions, modifications, and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. A high-performance shotcrete material for single-layer lining, characterized in that By weight ratio, it includes the following raw materials: 380 - 410 kg / m of cement 3 , 160 - 180 kg / m of water 3 , 800 - 900 kg / m of coarse aggregate 3 , 900 - 1000 kg / m of fine aggregate 3 , 30 - 40 kg / m of silica fume 3 , 6 - 10 kg / m of water reducing agent 3 , 25 - 30 kg / m of accelerating agent 3 , 6 - 10 kg / m of antifreeze 3 ; The antifreeze agent is composed of a photothermal conversion material, calcium nitrate, and barium oxide in a mass ratio of 1:(3 - 5):(1.5 - 3).

2. The high-performance shotcrete material for single-layer lining according to claim 1, wherein The cement is ordinary Portland cement with a strength grade of 42.5, an initial setting time of 50 min, and a final setting time of 200 min.

3. The high-performance shotcrete material for single-layer lining according to claim 1, wherein The coarse aggregate is continuously graded limestone gravel with a maximum particle size of 10 mm.

4. The high-performance shotcrete material for single-layer lining according to claim 1, wherein The fine aggregate is continuously graded manufactured sand with a fineness modulus of 2.5 - 3.

5. The high-performance shotcrete material for single-layer lining according to claim 1, characterized in that, The silicon powder mentioned above has a specific surface area of ≥20,000 m 2 / kg and a silicon dioxide content of ≥90%.

6. The high-performance shotcrete material for single-layer lining according to claim 1, characterized in that The water reducing agent is one or more of polycarboxylate superplasticizer and naphthalene series superplasticizer.

7. The high-performance shotcrete material for single-layer lining according to claim 1, characterized in that The accelerating agent is nanocrystalline rubber polymer.

8. The high-performance shotcrete material for single-layer lining according to claim 1, wherein The photothermal conversion material is azobenzene grafted graphene, and its preparation method is as follows: Graphene oxide is added to absolute ethanol, stirred and dispersed, then p - aminoazobenzene - 4 - sulfonic acid and dicyclohexylcarbodiimide are added, and the mixture is stirred and reacted at 70 - 75 °C for 3 - 5 h. After centrifugation, washing, and drying, azobenzene grafted graphene is obtained.

9. The high-performance shotcrete material for single-layer lining according to claim 1, characterized in that, The mass ratio of graphene oxide, absolute ethanol, p - aminoazobenzene - 4 - sulfonic acid, and dicyclohexylcarbodiimide is 1:10:(0.2 - 0.3):(0.03 - 0.05).

10. A method for preparing a high-performance shotcrete material for single-layer lining according to any one of claims 1-9, characterized in that, It includes the following steps: S1: Cement, water, coarse aggregate, fine aggregate, silica fume, and water reducing agent are mixed evenly to obtain a mixture. S2: An accelerating agent and an antifreeze agent are added to the mixture and stirred evenly to obtain a high - performance shotcrete material.

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