Concrete temperature control pouring maintenance method

Abstract

The invention discloses a concrete temperature control pouring maintenance method, and relates to the technical field of building construction. A concrete temperature control pouring maintenance method comprises the following steps that concrete is cooled to 15-35 DEG C, then pouring is conducted, a moisture permeable film is covered after pouring, the interval is 2-3 h, and a photo-thermal reflecting film is covered; after initial setting of the concrete, the concrete is covered with a heat preservation cotton felt and cured to a set age. The temperature of the concrete is controlled, heat accumulation of the concrete is avoided, the moisture permeable film covers the concrete in the pouring process, water vapor can be diffused from the interior of the high-humidity concrete to the low-humidity environment, and external liquid water cannot reversely permeate due to a hydrophobic layer and aperture limitation; the concrete is coated with the photo-thermal reflecting film, the photo-thermal reflecting film is reflected and absorbed into the paraffin in the daytime, heat is released at night, cooling loss of the concrete can be compensated, small day and night temperature difference fluctuation is achieved, finally, after initial setting of the concrete, the concrete is covered with the heat preservation cotton felt, the heat of the concrete is kept stable through the heat preservation cotton felt, temperature control over the concrete is achieved, and concrete cracking is avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of building construction, and particularly relates to a method for temperature control, pouring and curing of concrete. Background Art

[0002] Concrete has good mechanical properties and low engineering cost, and plays an important role in modern projects. It has become the most important mechanical material in modern architecture. Concrete can withstand strong compressive stress, but its tensile strength is weak. During the construction of concrete, a large amount of heat is generated during the hydration process of concrete, which is one of the key factors leading to poor crack resistance of concrete. The following are the problems existing in the prior art:

[0003] Temperature rise caused by hydration heat: During the hydration process of concrete, the internal temperature can rise to about 70°C or even higher. For mass concrete, the internal hydration heat can reach 50 - 60°C. The accumulation of this heat causes the internal temperature of concrete to rise sharply, while the surface dissipates heat quickly, thus forming a large temperature difference between the inside and the outside.

[0004] Cracks caused by temperature stress: Due to the temperature difference between the inside and the surface of concrete, the degree of thermal expansion and contraction inside and outside is different, resulting in tensile stress on the concrete surface. When the temperature difference of the concrete itself reaches 25°C - 26°C, tensile stress of about 10 MPa will be generated inside the concrete. If this tensile stress exceeds the tensile strength of the concrete, cracks will occur in the concrete.

[0005] Deficiencies of existing temperature control measures: Currently, the commonly used temperature control means include controlling the pouring temperature, water pipe cooling, surface heat dissipation of the bin, and surface heat preservation, etc. However, there are some problems in the actual application of these measures. For example, the arrangement of water pipes is too sparse, the cooling water temperature is too high, the thickness and heat preservation time of the surface heat preservation material are unreasonable, etc., resulting in poor temperature control effect. Cracks often occur after the concrete is poured, affecting the normal construction progress and safe operation of the project.

[0006] In summary, the heat problem during the hydration process of concrete in the prior art has not been effectively solved, and the crack resistance of concrete still needs to be further improved. Summary of the Invention

[0007] The technical problem to be solved by the present invention is the poor temperature control effect during the hydration process of concrete, which is likely to cause cracks. The purpose is to provide a method for temperature control, pouring and curing of concrete, which solves the heat problem during the hydration process of concrete.

[0008] The present invention is achieved by the following technical solutions:

[0009] A method for temperature control, pouring and curing of concrete includes the following steps:

[0010] Cool the concrete to 15 - 35 °C, then carry out pouring. After pouring, cover it with a moisture-permeable film, and after an interval of 2 - 3 h, cover it with a photothermal reflective film;

[0011] After the concrete begins to set, cover it with heat-insulating cotton felt and cure it to the set age.

[0012] As a possible design, the above-mentioned concrete cooling is specifically to adopt spray cooling and precooling during the concrete mixing stage;

[0013] During the pouring process, when the temperature is greater than 30 °C, add ice water or cold water for cooling;

[0014] During the pouring process, bury cooling water pipes in the concrete in a meandering manner. The horizontal burial spacing of the cooling water pipes is 1 - 2 m, the distance between the cooling water pipes and the concrete edge is 0.8 - 1.3 m, the wall thickness of the cooling water pipes is 1 - 1.5 mm, and the inner diameter is 30 - 40 mm.

[0015] As a possible design, the water passing temperature of the above-mentioned cooling water pipes is controlled at 17 - 27 °C, and the water passing flow rate of the cooling water pipes is 14 - 20 L / min.

[0016] As a possible design, the thickness of the above-mentioned moisture-permeable film is 0.1 - 0.4 mm;

[0017] The overlapping width between the moisture-permeable films is 5 - 15 cm;

[0018] The pore diameter of the inner layer of the moisture-permeable film is 20 - 60 nm, and the pore diameter of the outer layer is 100 - 200 nm.

[0019] As a possible design, the above-mentioned moisture-permeable film is prepared by the following method:

[0020] Mix polyethylene and polyurethane, and then add graphene oxide and mix evenly to obtain mixed particles;

[0021] Mix N,N-dimethylformamide and tetrahydrofuran to obtain a mixed solution;

[0022] Dissolve the mixed particles in the mixed solution to obtain spinning solution 1 and spinning solution 2 respectively. Use spinning solution 1 for electrospinning to obtain the inner layer, and then use spinning solution 2 for electrospinning on the inner layer to obtain the outer layer;

[0023] Weigh TiO 2 nanoparticles, ethanol and acetylacetone. Mix TiO 2 nanoparticles and ethanol evenly, add acetylacetone and stir for dispersion to obtain TiO 2 sol. Adopt ultrasonic atomization on the surface of the outer layer to spray TiO 2 sol and carry out ultraviolet curing to form TiO 2layer;

[0024] Weigh fluoroalkylsilane, multi-walled carbon nanotubes, isopropanol and surfactant. Add multi-walled carbon nanotubes to isopropanol, mix evenly, then add fluoroalkylsilane and surfactant, and stir magnetically for 3 - 4 hours to obtain a superhydrophobic aqueous solution. Spray the superhydrophobic aqueous solution on the TiO 2 layer, perform heat treatment, then hot press and shape, and treat with argon plasma.

[0025] As a possible design, the mass ratio of the above-mentioned polyethylene and polyurethane is 3 - 5:1;

[0026] The graphene oxide is 0.3 - 5% of the mass of the mixture of polyethylene and polyurethane;

[0027] The volume ratio of the N,N-dimethylformamide to tetrahydrofuran is 6 - 8:3;

[0028] The concentration of the spinning solution 1 is 10 - 20%, and the spinning solution 1 is electrospun under the conditions of 25 - 35 kV and 800 - 1200 rpm to obtain an inner layer with a diameter of 10 - 30 nm and a thickness of 30 - 70 μm;

[0029] The concentration of the spinning solution 2 is 5 - 15%, and the spinning solution 2 is electrospun under the conditions of 10 - 20 kV and 200 - 300 rpm to obtain an outer layer with a diameter of 100 - 300 nm and a thickness of 80 - 120 μm;

[0030] The TiO 2 nanoparticles, ethanol and acetylacetone. The mass ratio of TiO 2 nanoparticles to ethanol is 2 - 4:96.5 - 97:0.1 - 0.5;

[0031] The conditions for spraying the TiO 2 sol are 0.1 - 0.3 MPa, and the solid spraying amount of TiO 2 is 0.3 - 0.8 g / m 2 ;

[0032] The thickness of the TiO 2 layer is 150 - 250 nm.

[0033] As a possible design, the mass ratio of the above-mentioned fluoroalkylsilane, multi-walled carbon nanotubes, isopropanol and surfactant is 4 - 6:0.5 - 1.5:93.5 - 94:0.01 - 0.1;

[0034] After adding the fluoroalkylsilane and surfactant, stir magnetically for 3 - 4 hours;

[0035] The TiO 2The superhydrophobic aqueous solution is specifically sprayed on the layer at 0.2 - 0.4 MPa and with a solid spraying amount of fluoroalkylsilane of 0.3 - 0.8 g / m 2 Then, after spraying, it is heat-treated at 70 - 80 °C for 20 - 30 min, and then hot-pressed and shaped at 100 - 120 °C and 3 - 8 MPa, and plasma-treated with argon at a power of 80 - 100 w for 3 - 8 min.

[0036] As a possible design, the above-mentioned photothermal reflective film is prepared by the following method:

[0037] The carbon fiber cloth surface is treated by plasma with argon, and a silane coupling agent ethanol solution is sprayed, and the pre-treated base cloth is obtained after drying.

[0038] Weigh tetrabutyl titanate, zinc nitrate, nano-graphene, silicon dioxide, ethanol, chelating agent and deionized water. Mix tetrabutyl titanate, nano-graphene and silicon dioxide with ethanol, add the chelating agent dropwise, and then add zinc nitrate, stir evenly to obtain the photothermal reflective coating. Then, the photothermal reflective coating is coated on the pre-treated base cloth by electrostatic spraying, and then heated and kept warm to obtain the primary-treated base cloth.

[0039] Mix paraffin with carboxylated multi-walled carbon nanotubes, heat and melt them and disperse them by ultrasonic wave to obtain a suspension. Adjust the pH value of the polyvinyl alcohol solution to 8 - 9, drop the suspension into the polyvinyl alcohol solution, and stir and disperse to obtain an emulsion.

[0040] Dissolve polydopamine in hydrochloric acid buffer solution to obtain a dopamine hydrochloride solution with a concentration of 1 - 3 mg / mL. Drop the emulsion into the dopamine hydrochloride solution, and stir at a speed of 500 - 700 rpm for 4 - 5 h, and then separate the microcapsules, wash and dry them.

[0041] Dissolve amino-silane in ethanol solution to obtain an amino-silane solution. Dissolve the microcapsules in the amino-silane solution and disperse them by ultrasonic wave, and then perform heat treatment, filter to obtain the treated microcapsules. Disperse the treated microcapsules in ethanol to obtain a microcapsule solution, add a photoinitiator, stir evenly to obtain a photoinitiator solution, and soak the primary-treated base cloth in the photoinitiator solution after vacuum pumping, and take it out and cure it by ultraviolet light to obtain the photothermal reflective film.

[0042] As a possible design, the above-mentioned plasma treatment on the carbon fiber cloth surface is specifically carried out by plasma treatment with argon at a power of 120 - 150 W for 3 - 5 min;

[0043] The concentration of the silane coupling agent is 0.5 - 1%;

[0044] The mass ratio of tetrabutyl titanate, zinc nitrate, nano-graphene, silicon dioxide, ethanol, chelating agent and deionized water is 15 - 25:3 - 5:0.05 - 0.1:2 - 5:50 - 70:1 - 3:5 - 10;

[0045] When the photothermal reflective coating is applied to the pretreated base fabric by electrostatic spraying, the spraying voltage is 20 - 30 kV, the spraying speed is 0.2 - 0.4 mL / min, the nozzle is 10 - 20 cm away from the pretreated base fabric, the spraying thickness is 4 - 10 μm, and after spraying, it is kept warm at 200 - 300 °C for 30 - 40 min;

[0046] The mass ratio of paraffin wax to carboxylated multi-walled carbon nanotubes is 98 - 99:0.5 - 1;

[0047] The concentration of the polyvinyl alcohol solution is 1.5 - 3%;

[0048] When the suspension is dropped into the polyvinyl alcohol solution, it is stirred at a speed of 800 - 1200 rpm for 10 - 15 min;

[0049] The concentration of the dopamine hydrochloride solution is 1 - 3 mg / mL;

[0050] After the emulsion is dropped into the dopamine hydrochloride solution, it is stirred at a rotation speed of 500 - 700 rpm for 4 - 5 h;

[0051] The concentration of the amino silane solution is 1 - 3%;

[0052] The microcapsules are dissolved in the amino silane solution, ultrasonically dispersed, and then heat-treated at 50 - 70 °C for 0.5 - 1.5 h;

[0053] After treatment, the microcapsules are dispersed in ethanol to obtain a microcapsule solution with a concentration of 5 - 15%, and then a photoinitiator with a weight percentage of 1 - 3% of the solution is added.

[0054] As a possible design, the above-mentioned age is specifically:

[0055] The curing time of portland cement, ordinary portland cement and slag portland cement is 7 - 10 days;

[0056] The curing time of pozzolanic portland cement, fly ash portland cement and composite portland cement is 14 - 18 days;

[0057] The curing time of concrete with retarders, mineral admixtures or impermeability requirements is 14 - 18 days;

[0058] The curing time of waterproof concrete is 14 - 28 days;

[0059] The curing time of mass ordinary portland cement is 14 - 18 days;

[0060] The curing time for mass slag cement and mass pozzolanic cement is 21 - 25 days.

[0061] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0062] By controlling the temperature of the concrete and avoiding the accumulation of its heat, the present invention pours a thick covering of moisture-permeable film, enabling water vapor to diffuse from the high-humidity interior of the concrete to the low-humidity environment, while external liquid water cannot reverse osmosis due to the hydrophobic layer and pore size limitation; then covering with a photothermal reflective film, absorbing the heat during the day and releasing it at night, which can compensate for the temperature drop loss of the concrete, achieving a small fluctuation in the day-night temperature difference. Finally, after the concrete begins to set, covering with thermal insulation cotton felt, maintaining the heat stability of the concrete with the help of the thermal insulation cotton felt, realizing the temperature control of the concrete and avoiding the cracking of the concrete. Specific embodiments

[0063] 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 in conjunction with embodiments. The illustrative embodiments and descriptions of the present invention are only used to explain the present invention and are not intended to limit the present invention. Those not specified in the embodiments are carried out according to conventional conditions or conditions recommended by the manufacturer. Those reagents or instruments not specified by the manufacturer can be obtained as conventional products through commercial purchase.

[0064] A method for temperature control pouring and curing of concrete includes the following steps:

[0065] S1. Cool the concrete to 15 - 35°C, then carry out pouring. After pouring, cover with a moisture-permeable film, and after an interval of 2 - 3 hours, cover with a photothermal reflective film.

[0066] The moisture-permeable film covered after pouring has a double-layer large-pore and small-pore structure. The inner-layer nano-small pores can prevent the loss of liquid water, and the outer-layer large pores allow the unidirectional escape of water vapor, thus being able to balance the surface humidity of the concrete and reduce plastic shrinkage cracks; then laying a photothermal reflective film on it, which can reflect solar radiation during the day and absorb heat to release latent heat at night, can compensate for the temperature drop loss of the concrete, achieving a day-night temperature difference fluctuation ≤ 5°C, and further ensuring the stable setting and non-cracking of the concrete.

[0067] The above-mentioned cooling of the concrete is specifically achieved by spray cooling and precooling during the concrete mixing stage.

[0068] During the above-mentioned pouring process, when the temperature is greater than 30°C, add ice water or cold water for cooling.

[0069] During the pouring process, cooling water pipes are buried in the concrete in a meandering pattern. The horizontal spacing of the cooling water pipes is 1 - 2 m, the distance from the cooling water pipes to the concrete edge is 0.8 - 1.3 m, the wall thickness of the cooling water pipes is 1 - 1.5 mm, and the inner diameter is 30 - 40 mm. Preferably, the cooling water pipes are laid in a winding manner in the concrete. During the setting process of the concrete, the temperature will rise. The pre-embedded water pipes start the water circulation system, and the circulating water is used to absorb the hydration heat to reduce the temperature at the time of pouring into the mold, achieving dynamic temperature control. The inlet and outlet pipes between each layer are independent, so as to adjust the water circulation speed accordingly according to the temperature measurement data, making full use of the characteristics of the concrete itself, that is, the temperature in the middle is high and the temperature around is low, and automatically adjusting the temperature during the circulation process to produce good results. When installing the cooling pipes, they are firmly fixed with the steel bar skeleton, and the pipes are connected with colloidal pipes. To prevent pipe blockage and water leakage, a water passing test is carried out before concrete pouring.

[0070] After the concrete is poured to the height of the cooling water pipes in each layer, water cooling is started immediately to accelerate the dissipation of the internal heat of the concrete and reduce the internal temperature of the concrete to the required limit. The water cooling time is generally 15 ± 5 days after pouring. When the temperature of the concrete drops by more than 1.5 °C per day, the water supply is stopped.

[0071] The water passing temperature of the cooling water pipes is controlled at 17 - 27 °C for cooling, and it is ensured that the maximum temperature difference between the water temperature of the cooling water and the hydration heat in the concrete water pipes is controlled within 25 °C.

[0072] The water passing flow rate of the cooling water pipes is 14 - 20 L / min, so that the temperature difference between the inlet and outlet water of the cooling pipes is controlled not to exceed 10 °C. Preferably, the cooling rate is about 0.6 °C per day to avoid the concrete cracking caused by a large and steep temperature gradient. When it is found that the temperature difference between the inlet and outlet is too large or too small, or the temperature difference between the water temperature and the inside of the concrete exceeds 25 °C, the water temperature and flow rate are adjusted in time to prevent temperature cracks from occurring around the pipes.

[0073] The thickness of the above-mentioned moisture permeable membrane is 0.1 - 0.4 mm.

[0074] The overlapping width between the above-mentioned moisture permeable membranes is 5 - 15 cm.

[0075] The inner small hole diameter of the above-mentioned moisture permeable membrane is 20 - 60 nm, and the outer large hole diameter is 100 - 200 nm. The inner small holes lock the liquid water on the concrete surface, which can prevent plastic shrinkage cracks caused by early moisture loss; the outer large holes can enable the unidirectional escape of water vapor, balance the surface humidity, avoid condensation, and prevent surface softening or freeze-thaw damage. The combined setting of the large and small holes can enable the concrete to solidify stably.

[0076] The above-mentioned moisture permeable membrane is prepared by the following method:

[0077] A1. Mix polyethylene and polyurethane in a mass ratio of 3 - 5:1, and then add 0.3 - 5 wt% of graphene oxide to the polyethylene and polyurethane mixture, and mix evenly to obtain mixed particles.

[0078] The mixing of polyethylene and polyurethane can not only provide a hydrophobic skeleton for the subsequent spinning membrane, but also has good flexibility and fatigue resistance. At the same time, the addition of graphene oxide can provide good mechanical strength and thermal stability for the spinning membrane, improving the comprehensive performance of the moisture permeable membrane.

[0079] A2. Mix N,N-dimethylformamide (DMF) and tetrahydrofuran (THF) in a volume ratio of 6 - 8:3 to obtain a mixed solution.

[0080] The synergistic effect of the low viscosity of THF and the high polarity of DMF can effectively dissolve polymer materials such as PVDF to form a uniform spinning solution.

[0081] A3. Dissolve the mixed particles in the mixed solution to obtain spinning solution 1 with a concentration of 10 - 20% and spinning solution 2 with a concentration of 5 - 15% respectively. Use spinning solution 1 to electrospin at 25 - 35 kV and 800 - 1200 rpm to obtain an inner layer with a diameter of 10 - 30 nm and a thickness of 30 - 70 μm, and then use spinning solution 2 to electrospin at 10 - 20 kV and 200 - 300 rpm to obtain an outer layer with a diameter of 100 - 300 nm and a thickness of 80 - 120 μm.

[0082] The electrospinning of ultrafine fibers forms small pores in the inner layer, and the electrospinning of thick fibers forms large pores in the outer layer. The superposition of the two layers can not only lock the surface liquid water but also allow the diffusion of water vapor.

[0083] A4. Weigh TiO 2 nanoparticles, ethanol and acetylacetone in a mass ratio of 2 - 4:96.5 - 97:0.1 - 0.5. Mix the TiO 2 nanoparticles and ethanol evenly, add acetylacetone and stir to disperse to obtain TiO 2 sol. Adopt ultrasonic atomization on the outer layer surface, and spray TiO 2 sol under the conditions of 0.1 - 0.3 MPa and a TiO 2 solid spraying amount of 0.3 - 0.8 g / m 2 and carry out ultraviolet curing to form a TiO 2 layer with a thickness of 150 - 250 nm.

[0084] The sprayed TiO 2 generates electron-hole pairs under ultraviolet light, generating hydroxyl radicals (·OH) and superoxide radicals (·O 2 -) can decompose organic pollutants (such as oil stains, microorganisms), and at the same time, nano-TiO 2 particles form a micro-nano structure on the membrane surface, providing anchor points for the subsequent superhydrophobic layer.

[0085] A5. Weigh fluorosilane, multi-walled carbon nanotubes, isopropanol and surfactant according to the mass ratio of 4-6:0.5-1.5:93.5-94:0.01-0.1. Add multi-walled carbon nanotubes to isopropanol, mix evenly, then add fluorosilane and surfactant, and stir magnetically for 3-4 hours to obtain a superhydrophobic aqueous solution. Spray the superhydrophobic aqueous solution on the TiO 2 layer under the conditions of 0.2-0.4 MPa and a fluorosilane solid spraying amount of 0.3-0.8 g / m 2 and heat-treat at 70-80 °C for 20-30 min, then hot-press and shape at 100-120 °C and 3-8 MPa, and perform plasma treatment with argon at a power of 80-100 w for 3-8 min.

[0086] Fluorosilane forms Si-O-Si covalent bonds with the hydroxyl groups (-OH) on the membrane surface through hydrolysis and condensation reactions, reducing the surface energy. The multi-walled carbon nanotube network can improve the antistatic performance of the membrane, reduce dust adsorption, make the surface not easily stained, enhance the surface hydrophobicity at the same time, enhance the stability of the membrane layer, and facilitate cleaning and maintenance. The TiO 2 layer can photocatalytically degrade surface pollutants, and at the same time, the superhydrophobic layer can reduce the adhesion ability of pollutants, facilitate being washed away by water, and achieve a high surface cleaning effect.

[0087] The above photothermal reflective membrane is prepared by the following method:

[0088] B1. Perform plasma treatment on the surface of the carbon fiber cloth with argon at a power of 120-150 W for 3-5 min, spray the ethanol solution of silane coupling agent, and obtain the pretreated base cloth after drying, where the concentration of the silane coupling agent is 0.5-1%.

[0089] By performing plasma treatment on the surface of the carbon fiber, active groups such as hydroxyl groups can be introduced on its surface, improving the coating adhesion. Then spray the coupling agent to form a molecular bridging layer, enhancing the chemical bonding between the fiber and the subsequent coating, and improving the adhesion.

[0090] B2. Weigh tetrabutyl titanate, zinc nitrate, nano-graphene, silicon dioxide, ethanol, chelating agent and deionized water according to the mass ratio of 15 - 25:3 - 5:0.05 - 0.1:2 - 5:50 - 70:1 - 3:5 - 10. Mix tetrabutyl titanate, nano-graphene and silicon dioxide with ethanol, add the chelating agent dropwise, then add zinc nitrate, and stir evenly to obtain a photothermal reflective coating. Then, apply the photothermal reflective coating onto the pretreated base fabric by electrostatic spraying. The spraying voltage is 20 - 30 kV, the spraying speed is 0.2 - 0.4 mL / min, the nozzle is 10 - 20 cm away from the pretreated base fabric, the spraying thickness is 4 - 10 μm, and after spraying, keep it at 200 - 300 °C for 30 - 40 min to obtain a primary treated base fabric.

[0091] After hydrolysis, tetrabutyl titanate forms TiO 2 nanoparticles. These particles have good light reflection properties and can reflect visible light and near-infrared light in sunlight, thereby reducing the accumulation of solar radiation heat on the surface of the base fabric. TiO 2 combined with ZnO has a high ultraviolet-visible light reflectivity and can degrade surface pollutants through photocatalysis to maintain a high reflectivity; the added graphene can be used as a photothermal conversion enhancer to improve the near-infrared reflectivity and heat diffusion efficiency. At the same time, it can absorb ultraviolet light and convert it into heat energy to accelerate the heat diffusion in the coating and avoid local overheating; the addition of silicon dioxide can improve the denseness of the coating and prevent shedding.

[0092] B3. Mix paraffin and carboxylated multi-walled carbon nanotubes according to the mass ratio of 98 - 99:0.5 - 1, heat and melt them, and disperse them by ultrasonic to obtain a suspension. Adjust the pH value of the polyvinyl alcohol solution with a concentration of 1.5 - 3% to 8 - 9, drop the suspension into the polyvinyl alcohol solution, and stir at a speed of 800 - 1200 rpm for 10 - 15 min to obtain an emulsion.

[0093] Multi-walled carbon nanotubes form a three-dimensional network in paraffin, which can effectively improve the thermal conductivity and shorten the effective phase change time. The obtained emulsion has a water-in-oil structure.

[0094] B4. Dissolve polydopamine in a hydrochloric acid buffer solution to obtain a dopamine hydrochloride solution with a concentration of 1 - 3 mg / mL. Drop the emulsion into the dopamine hydrochloride solution, and stir at a speed of 500 - 700 rpm for 4 - 5 h, then separate the microcapsules and wash and dry them.

[0095] Dopamine hydrochloride oxidizes to form dopamine quinone under the above conditions and oxidatively self-polymerizes at the oil-water interface to form a polydopamine shell layer. This shell layer will form an amorphous dense layer due to π-π stacking and hydrogen bond interactions, which can protect the internal concrete.

[0096] B5. Dissolve the aminosilane in an ethanol solution to obtain an aminosilane solution with a concentration of 1-3%. Dissolve the microcapsules in the aminosilane solution and disperse them by ultrasonic treatment. Then, perform heat treatment at 50-70°C for 0.5-1.5 h, and filter to obtain the treated microcapsules. Disperse the treated microcapsules in ethanol to obtain a microcapsule solution with a concentration of 5-15%. Add a photoinitiator accounting for 1-3% by weight of the solution, stir evenly to obtain a photoinitiator solution, evacuate the primary treated base fabric and soak it in the photoinitiator solution, and then take it out and cure it under ultraviolet light to obtain a photothermal reflective film.

[0097] The amino group of the aminosilane condenses with the phenolic hydroxyl group of polydopamine, and at the same time forms a Si-O-Si bond with the silane layer (-Si-O-) on the surface of the carbon fiber, which can enhance the binding force between the microcapsules and the substrate. Then, it is mixed with the solution containing the photoinitiator. The photoinitiator absorbs ultraviolet light to generate active free radicals, triggering the cross-linking of epoxy resin. The binding strength between the microcapsules and the substrate can be improved through chemical bonds (the reaction between epoxy groups and hydroxyl groups on the surface of carbon fibers) and physical anchoring. Moreover, the flexibility of the epoxy resin can relieve the shrinkage stress of the concrete and prevent the microcapsules from cracking, achieving a high encapsulation rate, uniform particle size, and excellent thermal stability of the photothermal reflective film.

[0098] The above photoinitiator can be Irgacure 2959.

[0099] S2. After the initial setting of the concrete, cover it with a heat-insulating cotton felt and cure it until the set age.

[0100] The above age is specifically as follows:

[0101] Portland cement, ordinary Portland cement, slag Portland cement: The curing time is 7-10 days;

[0102] Volcanic ash Portland cement, fly ash Portland cement, composite Portland cement: The curing time is 14-18 days;

[0103] Concrete with retarders, mineral admixtures or impermeability requirements: The curing time is 14-18 days;

[0104] Waterproof concrete: The curing time is 14-28 days;

[0105] Mass ordinary Portland cement: The curing time is 14-18 days;

[0106] Mass slag cement, mass volcanic ash cement: The curing time is 21-25 days.

[0107] In some embodiments of the present invention, the above

[0108] Example 1

[0109] S1. During the concrete mixing stage, spray cooling and pre-cooling are adopted to cool the portland cement to 15 - 35°C, and then pouring is carried out. When the temperature is higher than 30°C, ice water or cold water is added for cooling. During the pouring process, cooling water pipes are buried in the concrete in a meandering manner. The horizontal burial spacing of the cooling water pipes is 1 m, the distance from the cooling water pipes to the concrete edge is 0.8 m, the wall thickness of the cooling water pipes is 1 mm, the inner diameter is 30 mm, the water passing temperature of the cooling water pipes is controlled at 22 ± 5°C, and the water passing flow rate of the cooling water pipes is generally 14 - 20 L / min. After pouring, a moisture-permeable film with a thickness of 0.1 mm is covered. The overlapping width between the moisture-permeable films is 5 cm. The pore diameter of the inner layer of the moisture-permeable film is 20 - 60 nm, and the pore diameter of the outer layer is 100 - 200 nm. After an interval of 2 h, a light and heat reflective film is covered.

[0110] The moisture-permeable film is prepared by the following method:

[0111] A1. Mix polyethylene and polyurethane in a mass ratio of 3:1, and then add 0.3 wt% of graphene oxide to the polyethylene and polyurethane mixture, and mix evenly to obtain mixed particles.

[0112] A2. Mix N,N-dimethylformamide (DMF) and tetrahydrofuran (THF) in a volume ratio of 6:3 to obtain a mixed solution.

[0113] A3. Dissolve the mixed particles in the mixed solution to obtain spinning solution 1 with a concentration of 10% and spinning solution 2 with a concentration of 5% respectively. Use spinning solution 1 to electrospin at 25 kV and 800 rpm to obtain an inner layer with a diameter of 10 - 30 nm and a thickness of 30 - 70 μm, and then use spinning solution 2 to electrospin at 10 kV and 200 rpm to obtain an outer layer with a diameter of 100 - 300 nm and a thickness of 80 - 120 μm.

[0114] A4. Weigh TiO 2 nanoparticles, ethanol and acetylacetone in a mass ratio of 2:96.5:0.1. Mix the TiO 2 nanoparticles and ethanol evenly, add acetylacetone and stir for dispersion to obtain TiO 2 sol. On the surface of the outer layer, adopt ultrasonic atomization method to spray TiO 2 sol under the conditions of 0.1 MPa and TiO 2 solid spraying amount of 0.3 g / m 2 and carry out ultraviolet curing to form a TiO 2 layer with a thickness of 150 - 250 nm.

[0115] A5. Weigh fluorosilane, multi-walled carbon nanotubes, isopropanol, and surfactant according to the mass ratio of 4:0.5:93.5:0.01. Add multi-walled carbon nanotubes to isopropanol, mix evenly, then add fluorosilane and surfactant, and stir magnetically for 3 hours to obtain a superhydrophobic aqueous solution. Under the conditions of 0.2 MPa and a fluorosilane solid spraying amount of 0.3 g / m 2 layer, spray the superhydrophobic aqueous solution on the TiO 2 layer, heat-treat at 70 - 80 °C for 20 min, then hot-press and shape at 100 °C and 3 MPa, and perform plasma treatment with argon at a power of 80 w for 3 min.

[0116] The above photothermal reflective film is prepared by the following method:

[0117] B1. Perform plasma treatment on the surface of the carbon fiber cloth with argon at a power of 120 W for 3 min, spray the ethanol solution of silane coupling agent, and dry to obtain a preliminarily treated base cloth, where the concentration of the silane coupling agent is 0.5%.

[0118] B2. Weigh tetrabutyl titanate, zinc nitrate, nano-graphene, silicon dioxide, ethanol, chelating agent, and deionized water according to the mass ratio of 15:3:0.05:2 - 5:50:1:5. Mix tetrabutyl titanate, nano-graphene, and silicon dioxide with ethanol, dropwise add the chelating agent, then add zinc nitrate, and stir evenly to obtain a photothermal reflective coating. Then coat the photothermal reflective coating on the preliminarily treated base cloth by electrostatic spraying. The spraying voltage is 20 kV, the spraying speed is 0.2 mL / min, the nozzle distance from the preliminarily treated base cloth is 10 cm, the spraying thickness is 4 - 10 μm, and after spraying, keep it at 200 °C for 30 min to obtain a once-treated base cloth.

[0119] B3. Mix paraffin and carboxylated multi-walled carbon nanotubes according to the mass ratio of 98 - 99:0.5 - 1, heat and melt and disperse ultrasonically to obtain a suspension. Adjust the pH value of the 1.5% polyvinyl alcohol solution to 8, drop the suspension into the polyvinyl alcohol solution, and stir at a speed of 800 rpm for 10 min to obtain an emulsion.

[0120] B4. Dissolve polydopamine in a hydrochloric acid buffer solution to obtain a 1 mg / mL dopamine hydrochloride solution. Drop the emulsion into the dopamine hydrochloride solution, and at the same time stir at a rotation speed of 500 rpm for 4 h, then separate the microcapsules and wash and dry.

[0121] B5. Dissolve the aminosilane in an ethanol solution to obtain an aminosilane solution with a concentration of 1%. Dissolve the microcapsules in the aminosilane solution and disperse them by ultrasonic treatment. Then, perform heat treatment at 50 °C for 0.5 h, and filter to obtain the treated microcapsules. Disperse the treated microcapsules in ethanol to obtain a microcapsule solution with a concentration of 5%. Add a photoinitiator with a weight percentage of 1% of the solution, stir evenly to obtain a photoinitiator solution, evacuate the primary treated base fabric and soak it in the photoinitiator solution, and take it out and perform ultraviolet curing after soaking to obtain a photothermal reflection film.

[0122] S2. After the concrete begins to set, cover it with a heat-insulating cotton felt and cure for 7 days.

[0123] Example 2

[0124] S1. During the concrete mixing stage, use spray cooling and precooling to cool the portland cement to 15 - 35 °C, and then perform pouring. When the temperature is higher than 30 °C, add ice water or cold water for cooling. During the pouring process, bury cooling water pipes in the concrete in a loop manner. The horizontal burial spacing of the cooling water pipes is 2 m, the distance between the cooling water pipes and the concrete edge is 1 m, the wall thickness of the cooling water pipes is 1.5 mm, the inner diameter is 35 mm, the water passing temperature of the cooling water pipes is controlled at 22 ± 5 °C, the water passing flow rate of the cooling water pipes is generally 14 - 20 L / min. After pouring, cover a moisture-permeable film with a thickness of 0.3 mm. The overlapping width between the moisture-permeable films is 10 cm. The inner layer small hole diameter of the moisture-permeable film is 20 - 60 nm, the outer layer large hole diameter is 100 - 200 nm, and cover the photothermal reflection film after an interval of 2.5 h.

[0125] The moisture-permeable film is prepared by the following method:

[0126] A1. Mix polyethylene and polyurethane in a mass ratio of 4:1, and then add 3 wt% of graphene oxide based on the mixture of polyethylene and polyurethane, and mix evenly to obtain mixed particles.

[0127] A2. Mix N,N-dimethylformamide (DMF) and tetrahydrofuran (THF) in a volume ratio of 7:3 to obtain a mixed solution.

[0128] A3. Dissolve the mixed particles in the mixed solution to obtain spinning solution 1 with a concentration of 15% and spinning solution 2 with a concentration of 10% respectively. Use spinning solution 1 to perform electrospinning at 30 kV and 1000 rpm to obtain an inner layer with a diameter of 10 - 30 nm and a thickness of 30 - 70 μm, and then use spinning solution 2 to perform electrospinning at 15 kV and 250 rpm to obtain an outer layer with a diameter of 100 - 300 nm and a thickness of 80 - 120 μm.

[0129] A4. Weigh TiO 2 nanoparticles, ethanol and acetylacetone according to a mass ratio of 3:96.8:0.8. Mix TiO2 The nanoparticles and ethanol are mixed evenly, and acetylacetone is added and stirred for dispersion to obtain TiO 2 sol. By means of ultrasonic atomization on the outer surface, TiO is sprayed under the conditions of 0.2 MPa and a solid spraying amount of TiO of 0.6 g / m 2 2 sol and then ultraviolet curing is carried out to form a TiO layer with a thickness of 150 - 250 nm. 2 2

[0130] A5. Weigh fluoroalkylsilane, multi-walled carbon nanotubes, isopropanol and surfactant according to the mass ratio of 5:1:93.8:0.05. Add the multi-walled carbon nanotubes to isopropanol, mix evenly, then add fluoroalkylsilane and surfactant, and stir magnetically for 4 hours to obtain a superhydrophobic aqueous solution. Under the conditions of 0.3 MPa and a fluoroalkylsilane solid spraying amount of 0.6 g / m 2 the superhydrophobic aqueous solution is sprayed on the TiO layer, and then heat treatment is carried out at 75 °C for 25 min, and then thermocompression molding is carried out under the conditions of 110 °C and 6 MPa, and plasma treatment is carried out with argon at a power of 90 w for 4 min. 2

[0131] The above photothermal reflection film is prepared by the following method:

[0132] B1. Plasma treatment is carried out on the surface of the carbon fiber cloth with argon at a power of 140 W for 4 min, and an ethanol solution of silane coupling agent is sprayed, and then the pretreated base cloth is obtained after drying, where the concentration of the silane coupling agent is 0.8%.

[0133] B2. Weigh tetrabutyl titanate, zinc nitrate, nano-graphene, silicon dioxide, ethanol, chelating agent and deionized water according to the mass ratio of 20:4:0.08:3:60:2:8. Mix tetrabutyl titanate, nano-graphene and silicon dioxide with ethanol, dropwise add the chelating agent, and then add zinc nitrate, stir evenly to obtain a photothermal reflection coating. Then the photothermal reflection coating is electrostatically sprayed onto the pretreated base cloth, the spraying voltage is 25 kV, the spraying speed is 0.3 mL / min, the nozzle distance from the pretreated base cloth is 15 cm, the spraying thickness is 4 - 10 μm, and after spraying, it is kept warm at 250 °C for 35 min to obtain the primary treated base cloth.

[0134] B3. Paraffin and carboxylated multi-walled carbon nanotubes are mixed according to the mass ratio of 98.5:0.5 - 1, heated and melted and ultrasonically dispersed to obtain a suspension. Adjust the pH value of the polyvinyl alcohol solution with a concentration of 1.5 - 3% to 8.5, drop the suspension into the polyvinyl alcohol solution, and stir at a speed of 1000 rpm for 13 min to obtain an emulsion.

[0135] ​​​​B4. Dissolve polydopamine in a hydrochloric acid buffer solution to obtain a dopamine hydrochloride solution with a concentration of 2 mg / mL. Drop the emulsion into the dopamine hydrochloride solution, and at the same time, stir at a speed of 600 rpm for 4.5 h. Then, separate the microcapsules and wash and dry them.

[0136] B5. Dissolve amino-silane in an ethanol solution to obtain an amino-silane solution with a concentration of 2%. Dissolve the microcapsules in the amino-silane solution and disperse them by ultrasonic treatment. Then, perform heat treatment at 60 °C for 1 h, filter to obtain the treated microcapsules. Disperse the treated microcapsules in ethanol to obtain a microcapsule solution with a concentration of 10%. Add a photoinitiator with a weight percentage of 2% of the solution, stir evenly to obtain a photoinitiator solution. After evacuating the primary treated base fabric, immerse it in the photoinitiator solution, take it out after immersion and cure it by ultraviolet light to obtain a heat and light reflection film.

[0137] S2. After the concrete begins to set, cover it with heat-insulating cotton felt and cure for 8 days.

[0138] Example 3

[0139] S1. During the concrete mixing stage, use spray cooling for precooling, cool the portland cement to 15 - 35 °C, and then perform pouring. When the temperature is higher than 30 °C, add ice water or cold water for cooling. During the pouring process, bury cooling water pipes in the concrete in a meandering manner. The horizontal burial spacing of the cooling water pipes is 2 m, the distance between the cooling water pipes and the concrete edge is 1.3 m, the wall thickness of the cooling water pipes is 1.5 mm, the inner diameter is 40 mm, the water passing temperature of the cooling water pipes is controlled at 22 ± 5 °C, and the water passing flow rate of the cooling water pipes is generally 14 - 20 L / min. After pouring, cover a moisture-permeable film with a thickness of 0.4 mm. The overlapping width between the moisture-permeable films is 15 cm. The inner pore diameter of the moisture-permeable film is 20 - 60 nm, and the outer pore diameter is 100 - 200 nm. After an interval of 3 h, cover the heat and light reflection film.

[0140] The moisture-permeable film is prepared by the following method:

[0141] A1. Mix polyethylene and polyurethane in a mass ratio of 5:1, and then add graphene oxide with a weight percentage of 5% of the polyethylene and polyurethane mixture, and mix evenly to obtain mixed particles.

[0142] A2. Mix N,N-dimethylformamide (DMF) and tetrahydrofuran (THF) in a volume ratio of 8:3 to obtain a mixed solution.

[0143] A3. Dissolve the mixed particles in the mixed solution to obtain spinning solution 1 with a concentration of 20% and spinning solution 2 with a concentration of 15% respectively. Use spinning solution 1 to electrospin at 35 kV and 1200 rpm to obtain an inner layer with a diameter of 30 nm and a thickness of 70 μm, and then use spinning solution 2 to electrospin at 20 kV and 300 rpm to obtain an outer layer with a diameter of 300 nm and a thickness of 120 μm.

[0144] A4. Weigh TiO 2 nanoparticles, ethanol and acetylacetone according to a mass ratio of 4:97:0.5. Mix the TiO 2 nanoparticles and ethanol evenly, add acetylacetone and stir to disperse, obtaining TiO 2 sol. Adopt the ultrasonic atomization method on the surface of the outer layer, and spray TiO 2 sol under the conditions of 0.3 MPa and a TiO 2 solid spraying amount of 0.8 g / m 2 and carry out ultraviolet curing to form a TiO 2 layer with a thickness of 150 - 250 nm.

[0145] A5. Weigh fluorosilane, multi-walled carbon nanotubes, isopropanol and surfactant according to a mass ratio of 6:1.5:94:0.1. Add the multi-walled carbon nanotubes to isopropanol, mix evenly, then add fluorosilane and surfactant, and stir magnetically for 4 hours to obtain a superhydrophobic aqueous solution. Spray the superhydrophobic aqueous solution on the TiO 2 layer under the conditions of 0.4 MPa and a fluorosilane solid spraying amount of 0.8 g / m 2 , heat-treat at 80 °C for 30 min, then hot-press and shape at 120 °C and 8 MPa, and perform plasma treatment with argon at a power of 100 w for 8 min.

[0146] The above photothermal reflection film is prepared by the following method:

[0147] B1. Perform plasma treatment on the surface of the carbon fiber cloth with argon at a power of 150 W for 5 min, spray the ethanol solution of silane coupling agent, and obtain the pretreated base cloth after drying, where the concentration of the silane coupling agent is 1%.

[0148] B2. Weigh tetrabutyl titanate, zinc nitrate, nano-graphene, silicon dioxide, ethanol, chelating agent and deionized water according to the mass ratio of 25:5:0.1:5:70:3:10. Mix tetrabutyl titanate, nano-graphene and silicon dioxide with ethanol, add the chelating agent dropwise, then add zinc nitrate, and stir evenly to obtain a photothermal reflection coating. Then, coat the photothermal reflection coating on the pretreated base fabric by electrostatic spraying. The spraying voltage is 30 kV, the spraying speed is 0.4 mL / min, the nozzle is 20 cm away from the pretreated base fabric, and the spraying thickness is 4 - 10 μm. After spraying, keep it at 300 °C for 40 min to obtain a primary treated base fabric.

[0149] B3. Mix paraffin and carboxylated multi-walled carbon nanotubes according to the mass ratio of 99:0.5, heat and melt them, and disperse them by ultrasonic wave to obtain a suspension. Adjust the pH value of the polyvinyl alcohol solution with a concentration of 1.5 - 3% to 9, drop the suspension into the polyvinyl alcohol solution, and stir at a speed of 1200 rpm for 15 min to obtain an emulsion.

[0150] B4. Dissolve polydopamine in hydrochloric acid buffer solution to obtain a dopamine hydrochloride solution with a concentration of 3 mg / mL. Drop the emulsion into the dopamine hydrochloride solution, and stir at a speed of 700 rpm for 5 h while separating out the microcapsules, then wash and dry them.

[0151] B5. Dissolve amino-silane in ethanol solution to obtain an amino-silane solution with a concentration of 3%. Dissolve the microcapsules in the amino-silane solution and disperse them by ultrasonic wave, then heat-treat them at 70 °C for 1.5 h, filter to obtain the treated microcapsules. Disperse the treated microcapsules in ethanol to obtain a microcapsule solution with a concentration of 15%. Add a photoinitiator with a weight percentage of 3% of the solution, stir evenly to obtain a photoinitiator solution, and soak the primary treated base fabric in the photoinitiator solution after evacuating it, then take it out and cure it by ultraviolet light to obtain a photothermal reflection film.

[0152] S2. After the concrete starts to set, cover it with heat-insulating cotton felt and cure it for 10 days.

[0153] Comparative Example 1

[0154] This comparative example is basically the same as Example 2, the difference is that: the moisture-permeable membrane is not used.

[0155] Comparative Example 2

[0156] This comparative example is basically the same as Example 2, the difference is that: the photothermal reflection film is not used.

[0157] Comparative Example 3

[0158] This comparative example is basically the same as Example 2, the difference is that: the moisture-permeable membrane and the photothermal reflection film are not used.

[0159] Experimental Example

[0160] (1). Concrete blocks were made from the concrete cured according to Examples 1 - 3 and Comparative Examples 1 - 3. The size of the concrete blocks was 150 mm × 150 mm × 150 mm. The compressive strength test was carried out with reference to GB / T 50081 - 2002 Standard Test Method for Mechanical Properties of Ordinary Concrete. The test results are shown in Table 1.

[0161] Table 1

[0162]

[0163]

[0164] It can be seen from Table 1 that the compressive strength of Example 2 is the best. According to common knowledge, concrete with high compressive strength usually has high density and strength, which enables it to resist the generation and expansion of cracks to a certain extent and can reflect the crack resistance of concrete.

[0165] (2). According to GB / T50082 Standard Test Method for Long - term and Durability Performance of Ordinary Concrete, the early - age cracking test was carried out on the concrete under the methods of Examples 1 - 3 and Comparative Examples 1 - 3. The test results are shown in Table 2. The anti - cracking grade of standard concrete is from Grade Ⅰ to Grade Ⅴ.

[0166] Grade Ⅰ: The cracks are very fine, the average crack area < 10 mm 2 , the number of cracked cracks per unit area < 10 pieces / m 2 , and the total crack area per unit area < 100 mm 2 / m 2 .

[0167] Grade Ⅱ: Meet 3 of the above conditions.

[0168] Grade Ⅲ: Meet 2 of the above conditions.

[0169] Grade Ⅳ: Meet 1 of the above conditions.

[0170] Grade Ⅴ: Do not meet any of the above conditions.

[0171] Table 2

[0172] Sample Early anti-cracking performance grade Example 1 Grade I Example 2 Grade I Example 3 Grade I Comparative Example 1 Grade II Comparative Example 2 Grade I Comparative Example 3 Grade II

[0173] It can be seen that the concrete curing methods of Examples 1 - 3 result in concrete that is not easily cracked and has good stability.

[0174] The specific embodiments described above further elaborate on the purpose, technical solutions, and beneficial effects of the present invention. It should be understood that the above description is only the specific embodiments of the present invention and is not used to limit the protection scope of the present invention. Any modifications, equivalent replacements, 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 concrete temperature control pouring and curing method, characterized in that: The steps include: Cool the concrete to 15-35℃ before pouring. Cover with a moisture permeable film after pouring. Cover with a light and heat reflective film after an interval of 2-3 hours. After the initial setting of the concrete, cover it with thermal insulation felt and cure it to the set age.

2. A concrete temperature control pouring and curing method according to claim 1, characterized in that: The concrete cooling is specifically performed by spray cooling precooling during the concrete mixing stage; During the pouring process, when the temperature is greater than 30°C, add ice water or cold water to cool down; During the pouring process, the cooling water pipes are buried in the concrete in a zigzag manner. The horizontal buried spacing of the cooling water pipes is 1-2m, the spacing between the cooling water pipes and the edge of the concrete is 0.8-1.3m, the wall thickness of the cooling water pipes is 1-1.5mm, and the inner diameter is 30-40mm.

3. A concrete temperature control pouring and curing method according to claim 1, characterized in that: The water flow temperature of the cooling water pipe is controlled at 17-27°C, and the water flow rate of the cooling water pipe is 14-20L / min.

4. A concrete temperature control pouring and curing method according to claim 1, characterized in that: The moisture permeable film has a thickness of 0.1-0.4 mm; The overlap width between the moisture permeable films is 5-15 cm; The inner layer of the moisture permeable membrane has a pore size of 20-60 nm, and the outer layer has a pore size of 100-200 nm.

5. A concrete temperature control pouring and curing method according to claim 1 or 4, characterized in that: The moisture permeable membrane is prepared by the following method: Mixing polyethylene and polyurethane, adding graphene oxide, and mixing evenly to obtain mixed particles; Mixing N,N-dimethylformamide and tetrahydrofuran to obtain a mixed solution; The mixed particles are dissolved in a mixed solution to obtain spinning solution 1 and spinning solution 2 respectively, the spinning solution 1 is used for electrospinning to obtain an inner layer, and the spinning solution 2 is used for electrospinning on the inner layer to obtain an outer layer; Weigh TiO2 nanoparticles, ethanol and acetylacetone, mix the TiO2 nanoparticles and ethanol evenly, add acetylacetone and stir to disperse, to obtain TiO2 sol, spray the TiO2 sol on the surface of the outer layer by ultrasonic atomization and perform ultraviolet curing to form a TiO2 layer; Weigh fluorosilane, multi-walled carbon nanotubes, isopropanol and a surfactant, add the multi-walled carbon nanotubes to the isopropanol, mix evenly, then add fluorosilane and the surfactant, magnetically stir for 3-4 hours to obtain a superphobic solution, spray the superphobic solution on the TiO2 layer, heat treat, hot press to shape, and treat with argon plasma.

6. A concrete temperature control pouring and curing method according to claim 5, characterized in that: The mass ratio of polyethylene to polyurethane is 3-5:1; The graphene oxide is 0.3-5% by mass of the mixture of polyethylene and polyurethane; The volume ratio of N,N-dimethylformamide to tetrahydrofuran is 6-8:3; The concentration of the spinning solution 1 is 10-20%, and the spinning solution 1 is electrospun at 25-35 kV and 800-1200 rpm to obtain an inner layer with a diameter of 10-30 nm and a thickness of 30-70 μm; The concentration of the spinning solution 2 is 5-15%, and the spinning solution 2 is electrospun at 10-20 kV and 200-300 rpm to obtain an outer layer with a diameter of 100-300 nm and a thickness of 80-120 μm; The TiO2 nanoparticles, ethanol and acetylacetone, wherein the mass ratio of the TiO2 nanoparticles to the ethanol is 2-4:96.5-97:0.1-0.5; The conditions for spraying TiO2 sol are 0.1-0.3MPa and TiO2 solid spraying amount 0.3-0.8g / m 2 ; The thickness of the TiO2 layer is 150-250nm.

7. A concrete temperature control pouring and curing method according to claim 5, characterized in that: The mass ratio of the fluorosilane, multi-walled carbon nanotubes, isopropanol and surfactant is 4-6:0.5-1.5:93.5-94:0.01-0.1; After the fluorosilane and surfactant are added, magnetic stirring is performed for 3-4 hours; The super-repellent solution sprayed on the TiO2 layer is specifically 0.2-0.4MPa, and the fluorosilane solid spraying amount is 0.3-0.8g / m 2 After spraying, it is heated at 70-80℃ for 20-30min, then hot-pressed at 100-120℃ and 3-8MPa, and plasma treated with argon at 80-100w for 3-8min.

8. A concrete temperature control pouring and curing method according to claim 1, characterized in that: The photothermal reflective film is prepared by the following method: The surface of the carbon fiber cloth is treated with plasma using argon gas, and a silane coupling agent ethanol solution is sprayed on the surface, and then dried to obtain a primary treated base cloth. Weigh tetrabutyl titanate, zinc nitrate, nano-graphene, silicon dioxide, ethanol, a chelating agent and deionized water, mix tetrabutyl titanate, nano-graphene and silicon dioxide with ethanol, drop the chelating agent, add zinc nitrate, stir evenly to obtain a photothermal reflective coating, and then apply the photothermal reflective coating to the initially treated base fabric by electrostatic spraying, and then heat and keep warm to obtain a once treated base fabric. Paraffin wax and carboxylated multi-walled carbon nanotubes are mixed, heated to melt and ultrasonically dispersed to obtain a suspension, the pH value of the polyvinyl alcohol solution is adjusted to 8-9, the suspension is added dropwise to the polyvinyl alcohol solution, stirred and dispersed to obtain an emulsion. Dissolve polydopamine in hydrochloric acid buffer to obtain 1-3 mg / mL dopamine hydrochloride solution, drop the emulsion into the dopamine hydrochloride solution, and stir at 500-700 rpm for 4-5 hours, then separate the microcapsules, wash and dry. Dissolve aminosilane in ethanol solution to obtain aminosilane solution, dissolve microcapsules in the aminosilane solution and ultrasonically disperse, perform heat treatment, filter to obtain treated microcapsules, disperse the treated microcapsules in ethanol to obtain microcapsule solution, add photoinitiator, stir evenly to obtain photoinitiator solution, evacuate the treated base fabric and immerse it in the photoinitiator solution, take it out after immersion and perform ultraviolet curing to obtain a photothermal reflective film.

9. A concrete temperature control pouring and curing method according to claim 8, characterized in that: The carbon fiber cloth surface plasma treatment is specifically performed by using argon gas at a power of 120-150W for 3-5 minutes; The concentration of the silane coupling agent is 0.5-1%; The mass ratio of tetrabutyl titanate, zinc nitrate, nanographene, silicon dioxide, ethanol, chelating agent and deionized water is 15-25:3-5:0.05-0.1:2-5:50-70:1-3:5-10; The light and heat reflective coating is applied to the pre-treated base fabric by electrostatic spraying at a spraying voltage of 20-30 kV, a spraying speed of 0.2-0.4 mL / min, a nozzle distance of 10-20 cm from the pre-treated base fabric, a spraying thickness of 4-10 μm, and after spraying, the coating is kept at 200-300° C. for 30-40 minutes; The mass ratio of the paraffin wax to the carboxylated multi-walled carbon nanotubes is 98-99:0.5-1; The concentration of the polyvinyl alcohol solution is 1.5-3%; When the suspension is added dropwise to the polyvinyl alcohol solution, the mixture is stirred at a speed of 800-1200 rpm for 10-15 min; The concentration of the dopamine hydrochloride solution is 1-3 mg / mL; After the emulsion is dropped into the dopamine hydrochloride solution, the mixture is stirred at a speed of 500-700 rpm for 4-5 hours; The concentration of the aminosilane solution is 1-3%; The microcapsules are dissolved in an aminosilane solution and ultrasonically dispersed, followed by heat treatment at 50-70° C. for 0.5-1.5 h; The treated microcapsules are dispersed in ethanol to obtain a microcapsule solution with a concentration of 5-15%, and then a photoinitiator with a weight percentage of 1-3% is added to the solution.

10. A concrete temperature control pouring and curing method according to claim 1, characterized in that: The age period is specifically: The curing time for Portland cement, ordinary Portland cement and slag Portland cement is 7-10 days; The curing time for pozzolanic silicate cement, fly ash silicate cement and composite silicate cement is 14-18 days; The curing time for concrete with retarders, mineral admixtures or anti-seepage requirements is 14-18 days; The curing time for waterproof concrete is 14-28 days; The curing time for large volumes of ordinary Portland cement is 14-18 days; The curing time for bulk slag cement and bulk pozzolanic cement is 21-25 days.

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