High-performance concrete floor deck material and method of making

Abstract

The application provides a high-performance concrete floor support plate material and a preparation method thereof, and belongs to the technical field of concrete materials. The preparation of the high-performance concrete comprises the following steps: mixing and stirring arabinose, glycine and deionized water, adding silica fume dispersion, and spray drying to obtain modified silica fume; uniformly mixing ethyl silicate, ammonia water and anhydrous ethanol, spraying on the surface of medium sand, then spraying an alcohol solution of stearic acid, and drying and cooling to obtain modified medium sand; mixing cement, modified silica fume and activated fly ash, adding modified medium sand and gravel, and dry mixing to obtain mixed dry materials; mixing deionized water and a polycarboxylic acid water reducing agent into a solution, adding the solution into the mixed dry materials twice, and stirring uniformly to obtain the high-performance concrete. The flowability and early strength of the high-performance concrete are improved through the modification of the silica fume and the medium sand and the activation treatment of the fly ash.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of concrete materials, in particular to a high-performance concrete floor support plate material and a preparation method thereof. BACKGROUND

[0002] Concrete is one of the most commonly used structural materials in modern construction engineering, with characteristics such as abundant raw materials, low cost, good forming performance, and excellent mechanical properties. In the construction of concrete floor support plates, concrete not only bears the load and force transmission, but also directly affects the construction convenience and service performance of the floor system. In high-performance concrete floor support plates, not only is it required that the concrete has good late strength, but also it needs to have good fluidity and early strength: good fluidity can ensure that the concrete is uniformly poured and formed in the complex space with densely arranged steel trusses, thereby improving the construction efficiency; and higher early strength can meet the load-bearing requirements of the floor support plate in a short time, thereby improving the overall progress of the project.

[0003] In terms of concrete raw materials, cement and aggregate are usually used as the base, with mineral admixtures such as fly ash, slag powder, and silica fume being added, and polycarboxylic acid water reducer being used as an auxiliary agent for concrete preparation. Although silica fume can improve the density of concrete, it often leads to an increase in the viscosity of concrete, resulting in a decrease in fluidity; the activity of fly ash is released slowly and mainly plays a role in the later stage, which has limited effect on the improvement of early strength. Therefore, such a proportioning system often cannot balance fluidity and early strength while ensuring late strength, leading to problems such as pouring difficulty and slow project progress.

[0004] To solve the above problems, the existing technology often adjusts the process route or raw material proportioning to improve the performance of concrete. For example, the patent application file with publication number CN114133179A discloses a high-strength concrete gravel plate and a preparation method thereof, in which the process route is to first lay the aggregate in the forming mold, then pour the filling material composed of cement, water, fly ash, silica fume, iron ore sand, and water reducing agent into the forming mold, and combine the aggregate and the filling material by vibration. This scheme solves the problem of pouring difficulty caused by poor fluidity of concrete, but also has the defect that the aggregate and the filling material are difficult to fully and uniformly combine, which can easily lead to a decrease in the overall strength of the concrete, especially the lack of early strength.

[0005] In summary, there is a need to provide a high-performance concrete floor support plate material and a preparation method thereof to solve the problems of the existing technology. SUMMARY

[0006] To solve the problems of poor fluidity and low early strength of concrete in the existing technology, which lead to low construction efficiency and slow project progress of the floor support plate, the present application provides a high-performance concrete floor support plate material and a preparation method thereof.

[0007] To achieve the above object, the application provides a preparation method of a high-performance concrete floor support plate material, which comprises high-performance concrete and a steel bar truss, and comprises the following preparation steps:

[0008] S1, mixing arabinose, glycine and deionized water, heating and stirring, adding silica fume, ultrasonic dispersion, cooling, spray granulation, drying, sieving, and preparing modified silica fume;

[0009] S2, uniformly mixing ethyl silicate, ammonia water and anhydrous ethanol, spraying on the surface of medium sand, rolling and stirring, spraying stearic acid alcohol solution on the surface of the medium sand, drying, and cooling to prepare modified medium sand;

[0010] S3, mixing cement, modified silica fume and fly ash, adding modified medium sand and gravel, and dry mixing to obtain mixed dry materials;

[0011] S4, mixing deionized water and polycarboxylate superplasticizer to prepare a superplasticizer solution, slowly adding part of the superplasticizer solution to the mixed dry materials, stirring, adding the remaining superplasticizer solution, and continuously stirring until uniform to obtain high-performance concrete; pouring the high-performance concrete on the steel bar truss, vibrating, curing, and obtaining the high-performance concrete floor support plate material.

[0012] In the application, a composite thin layer composed of arabinose / glycine is constructed on the surface of silica fume, and a reversible "bonding" is formed at the contact points of silica fume particles by using a spray drying method to prepare modified silica fume. Thus, the originally highly dispersed silica fume is assembled into larger weakly bonded micro-particles, the specific surface area of the silica fume is reduced, and the water demand is reduced. At the same time, the hydroxyl groups provided by arabinose reduce the water contact angle of the surface of the weakly bonded micro-particles, so that the water film is more uniformly spread on the surface of the weakly bonded micro-particles; the zwitterionic property (-NH3 + / -COO - ) of glycine can slow down the rupture of the water film on the surface of the weakly bonded micro-particles, so that the wettability is more stable; the combination of arabinose and glycine improves the effective utilization rate of unit deionized water, reduces the viscosity of the material, and improves the fluidity of the concrete. Secondly, during the hardening process of the concrete, due to the action of the strong alkali environment, the arabinose / glycine composite thin layer gradually dissolves, the weakly bonded micro-particles disintegrate into single silica fume particles and gradually re-disperse into the micro-pores between the cement particles, so that the density of the concrete is improved, and the subsequent growth of the strength of the concrete is driven. Overall, through the method of "first particle, then disintegration", the effects of reducing the water demand and improving the fluidity in the mixing stage, and restoring the fineness of silica fume and improving the strength of the concrete in the hardening stage are realized.

[0013] It should be understood that the medium sand used in the present application is machine-made sand. In the present application, the modified medium sand forms a dense organic / inorganic composite film on the surface of the medium sand by stepwise spraying and heat drying treatment of ethyl metasilicate, ammonia and stearic acid, which is composed of an inner inorganic siloxane film and an outer stearic acid film. Ethyl metasilicate undergoes hydrolysis and condensation reaction under the catalysis of ammonia to form a continuous Si-O-Si network structure. The inorganic siloxane film can penetrate into and fill the pores and cracks on the surface of the machine-made sand, forming a dense inner inorganic siloxane film, thereby achieving physical plugging of the pores and cracks and surface polishing, so that the surface of the machine-made sand changes from rough to smooth. The subsequent spraying of stearic acid alcohol solution forms an ordered arrangement of long-chain alkyl molecular layer outside the inorganic siloxane film, which constitutes the outer stearic acid film, reduces the surface energy and improves the hydrophobicity of the machine-made sand. The organic / inorganic composite film can prevent deionized water from penetrating into the machine-made sand during the mixing stage, reduce the instantaneous water absorption, weaken the friction between particles and enhance the lubrication, so that the fluidity of the concrete is improved; during the hardening stage, the outer stearic acid film gradually saponifies and falls off, and the inner inorganic siloxane film slowly dissolves to form Si(OH)4, which reacts with the cement hydration product to form C-S-H gel, thereby forming a cementing layer at the sand-mortar interface, improving the interface density and the overall strength of the concrete.

[0014] Optionally, the steel bar truss is welded by a bottom steel plate, a middle steel bar network and a supporting steel bar. The bottom steel plate is self-provided with a formwork and a construction platform, thereby reducing temporary support and facilitating construction.

[0015] Optionally, the fly ash is surface treated by zinc lactate / sodium citrate and is subjected to alkaline hydrothermal aging to obtain the activated fly ash.

[0016] Optionally, the activated fly ash is prepared by mixing sodium citrate, zinc lactate, sodium hydroxide and deionized water, stirring at a speed of 400-450 rpm for 10-15 min, adding fly ash, stirring at a speed of 2000-2500 rpm for 8-10 min, ultrasonicating for 20-30 min, heating to 70-80 °C and stirring for 1-2 h, and centrifugal dewatering for 3-5 min to obtain wet materials, which are subjected to hydrothermal aging in an alkaline air environment, dried for 2-3 h, cooled to room temperature and then sieved through a 100 mesh sieve.

[0017] The activated fly ash in the present application is mainly fly ash, which is surface treated by zinc lactate / sodium citrate and is subjected to alkaline hydrothermal aging to construct an activated shell layer on the particle surface. During the activation treatment of the fly ash, the alkaline air environment provided by the saturated Ca(OH)2 solution promotes the reaction between zinc lactate / sodium citrate and the silicon and aluminum elements on the surface of the fly ash to form Zn-O-Si and Zn-O-Al bonds, and through the Na + and Ca2+ The ion exchange destroys the network structure of the fly ash surface, so that the originally dense glass phase shell of the fly ash is "softened", so that the fly ash is more likely to release Si and Al active components in the early hardening process of the concrete, and reacts with Ca(OH)2 generated by cement hydration to generate cementitious products such as calcium silicate hydrate (C-S-H) and calcium aluminate hydrate (C-A-H), so that the continuity of the gel structure in the early hardening process of the concrete is improved, so that the early activity of the fly ash is released and utilized efficiently, and the early strength of the concrete is improved.

[0018] Optionally, the step of heating and aging the wet material in an alkaline air environment comprises: uniformly laying the wet material in a tray and placing it in a sealed container, placing saturated Ca(OH)2 solution at the bottom of the sealed container, and heating the sealed container to 85-95 DEG C for 1-2 h; when the wet material is uniformly laid in the tray, the laying thickness of the wet material is ≤8 mm.

[0019] In the present application, the laying thickness of the wet material is ≤8 mm, which is beneficial to the uniform penetration of alkaline steam, reduces the difference between the inner and outer layers and the caking phenomenon, improves the aging efficiency and improves the consistency of the fly ash treatment effect.

[0020] Optionally, the deionized water and the polycarboxylic acid water reducing agent are mixed and stirred uniformly to obtain a water reducing agent solution, 2 / 3 of the water reducing agent solution is added to the mixed dry material, stirred at a speed of 60-90 r / min for 90-120 s, the remaining water reducing agent solution is added, and stirred for 120-150 s to obtain high-performance concrete.

[0021] Optionally, the modified silica ash is obtained by mixing arabinose, glycine and deionized water, heating to 50-55 DEG C, stirring at a speed of 400-450 rpm for 15-20 min, adding silica ash, stirring at a speed of 2000-2500 rpm for 8-10 min, ultrasonic for 30-40 min, and cooling to room temperature to obtain a mixture, pouring the obtained mixture into a spray dryer, continuously spraying and drying the mixture to a water content of ≤1.5wt%, and cooling to room temperature to pass through a 300 mesh sieve.

[0022] Optionally, the medium sand is poured into a roller type spraying device, continuously rolled at a speed of 20-30 rpm at 25-35 DEG C, and the ethyl silicate, ammonia water and 100-120 parts by mass of anhydrous ethanol are mixed and sprayed on the surface of the medium sand; then spray the stearic acid alcohol solution, dry at 60-75 DEG C for 15-20 min, and cool to room temperature to obtain modified medium sand.

[0023] In the present application, the water content of the mixture is controlled to ≤1.5wt%, which can reduce the hygroscopic caking, and the modified silica ash with uniform particle size is obtained by passing through a 300 mesh sieve, which is beneficial to improving the uniformity of the material.

[0024] Optionally, the crushed stone is continuously graded crushed stone, prepared with reference to the national standard GB / T 14685-2011 "Crushed Stone and Gravel for Construction"; preferably, the particle size range of the continuously graded crushed stone is 5~20mm.

[0025] In this invention, the combined use of continuously graded crushed stone with a particle size range of 5-20mm and medium sand increases the bulk density of the crushed stone, enabling it to uniformly fill the pores between the stones and reduce internal porosity. The continuously graded crushed stone improves the interlocking effect between large and small stones, forming a stable skeletal structure, while the use of medium sand enhances the coating of cement and fly ash onto the crushed stone, improving the density of the interfacial transition zone. In this way, the overall concrete structure becomes more continuous and uniform, thereby increasing the strength of the concrete.

[0026] A high-performance concrete floor deck material, wherein the high-performance concrete comprises the following raw materials in parts by weight: 200-220 parts deionized water, 10-15 parts polycarboxylate superplasticizer, and 1990-2280 parts mixed dry materials.

[0027] Optionally, the mixed dry material includes the following raw materials in parts by weight: 400-450 parts cement, 60-80 parts modified silica fume, 650-750 parts modified medium sand, and 800-900 parts crushed stone, wherein the cement is P·O52.5 ordinary Portland cement.

[0028] The modified silica fume comprises the following raw materials in parts by weight: 1.5-2.0 parts arabinose, 0.6-0.8 parts glycine, 500-550 parts deionized water, and 80-90 parts silica fume;

[0029] The modified medium sand comprises the following raw materials in parts by weight: 650-750 parts medium sand, 1-2 parts ethyl metasilicate, 0.1-0.3 parts 25wt% ammonia water, and 0.5-0.8 parts stearic acid, wherein the medium sand is manufactured sand.

[0030] Optionally, the mixed dry material further includes 80-100 parts of activated fly ash, which comprises the following raw materials in parts by weight: 0.8-1.2 parts of sodium citrate, 1-1.5 parts of zinc lactate, 0.3-0.5 parts of sodium hydroxide, 150-170 parts of deionized water, and 80-100 parts of fly ash.

[0031] The above-described technical solution of the present invention has at least the following beneficial effects:

[0032] This invention modifies silica fume by constructing an arabinose / glycine composite thin layer on the surface of silica fume and spray-drying it to form reversible adhesion at the particle contact points, thereby obtaining weakly bonded micro-aggregates and reducing its specific surface area and water demand. The hydroxyl groups of arabinose can reduce the water contact angle on the surface of the weakly bonded micro-aggregates, making the water film easier to spread evenly; the zwitterionic properties of glycine can slow down the water film rupture and improve wetting stability; the two work synergistically to improve the effective utilization rate of deionized water per unit and reduce viscosity, thereby improving the fluidity of concrete. During the hardening process, the composite thin layer gradually dissolves under the action of strong alkali, and the weakly bonded micro-aggregates disintegrate into individual silica fume particles and redisperse, exerting a micro-filling effect to enter the fine voids between cement particles, increasing density and driving strength growth.

[0033] In this invention, modified medium sand undergoes a stepwise spraying and thermal drying process using ethyl metasilicate, ammonia, and stearic acid to form an organic / inorganic composite film on its surface. This film consists of an inner inorganic silica film and an outer stearic acid film. Ethyl metasilicate undergoes hydrolysis and condensation under ammonia catalysis to generate a Si-O-Si network structure, forming an inorganic silica film that penetrates and fills the pores on the surface of the manufactured sand, resulting in a dense and smooth sand grain surface. Subsequently, a sprayed stearic acid alcohol solution forms an alkyl molecular layer outside the inorganic silica film, constituting the outer stearic acid film, which reduces surface energy and enhances hydrophobicity. This organic / inorganic composite film reduces water absorption and interparticle friction during the mixing stage, improving the fluidity of the concrete. During the hardening stage, the outer stearic acid film gradually saponifies and detaches, while the inner inorganic silica film slowly dissolves and reacts with the cement, forming a cementing layer at the sand-mortar interface, thus increasing the concrete strength. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. The described embodiments are some embodiments of the present invention, and all other embodiments obtained by those skilled in the art based on the described embodiments of the present invention are within the scope of protection of the present invention.

[0035] Example 1

[0036] Add 1.5 parts arabinose and 0.6 parts glycine to 500 parts deionized water, heat to 50°C, mechanically stir at 400 rpm for 15 min, slowly add 80 parts silica fume, stir at 2000 rpm for 8 min, disperse under 40 kHz ultrasonic conditions for 30 min, cool to room temperature, pour the resulting mixture into a spray dryer, set the inlet air temperature to 170°C and the outlet air temperature to 85°C, continuously spray dry until the moisture content of the mixture reaches 1.5 wt%, cool to room temperature and pass through a 300-mesh sieve to obtain modified silica fume.

[0037] 650 parts of medium sand were poured into a roller spraying device and slowly rolled at 20 rpm at 30°C. 1 part of ethyl metasilicate, 0.1 part of ammonia (25 wt%) and 100 parts of anhydrous ethanol were mixed and stirred evenly, and then sprayed onto the surface of the medium sand at a speed of 10 parts / min. Then, 0.5 parts of stearic acid and 100 parts of anhydrous ethanol were mixed evenly and sprayed onto the surface of the medium sand at a speed of 10 parts / min. The mixture was dried under hot air at 60°C for 15 min and cooled to room temperature to obtain modified medium sand.

[0038] 0.8 parts sodium citrate, 1 part zinc lactate, and 0.3 parts sodium hydroxide were added to 150 parts deionized water and mechanically stirred at 400 rpm for 10 min. 80 parts fly ash were slowly added and dispersed by stirring at 2000 rpm for 8 min. The mixture was then dispersed under ultrasonic conditions at 40 kHz for 20 min. The mixture was heated to 70℃ and stirred for 1 h. After centrifugation at 1000 rpm for 3 min, wet material was obtained. The wet material was evenly spread in a tray and placed in a sealed container with a thickness of 4 mm. An open dish containing saturated Ca(OH)2 solution was placed at the bottom of the container to provide an alkaline air environment. The mixture was hydrothermally aged at 85℃ for 1 h. The sample was then removed and dried at 105℃ for 2 h. After cooling to room temperature, the sample was passed through a 100-mesh sieve to obtain activated fly ash.

[0039] Mix 400 parts of P·O52.5 ordinary Portland cement, 80 parts of activated fly ash and 60 parts of modified silica fume, add 650 parts of modified medium sand and 800 parts of continuously graded crushed stone (particle size range of 5~20mm), and dry mix for 30s to obtain the mixed dry material.

[0040] Mix 200 parts of deionized water and 10 parts of polycarboxylate superplasticizer, stir evenly to obtain a superplasticizer solution, slowly add 2 / 3 of the superplasticizer solution to the mixed dry material, stir at 60 r / min for 90 s, then add the remaining 1 / 3 of the superplasticizer solution, and continue stirring for 120 s to obtain high-performance concrete.

[0041] High-performance concrete is poured onto a steel truss, compacted with a vibrating device, and cured for 24 hours to obtain high-performance concrete floor deck material.

[0042] Example 2

[0043] 1.8 parts of arabinose and 0.7 parts of glycine were added to 520 parts of deionized water, heated to 53°C, and mechanically stirred at 420 rpm for 18 min. 85 parts of silica fume were slowly added, and the mixture was stirred at 2200 rpm for 9 min. The mixture was then dispersed under ultrasonic conditions at 45 kHz for 35 min and cooled to room temperature. The resulting mixture was poured into a spray dryer with an inlet air temperature of 175°C and an outlet air temperature of 85°C. The mixture was continuously spray-dried until the moisture content of the mixture reached 1.2 wt%. After cooling to room temperature, the mixture was passed through a 300-mesh sieve to obtain modified silica fume.

[0044] 700 parts of medium sand were poured into a roller spraying device and slowly rolled at 25 rpm at 32°C. 1.5 parts of ethyl metasilicate, 0.2 parts of ammonia (25 wt%) and 110 parts of anhydrous ethanol were mixed and stirred evenly, and then sprayed onto the surface of the medium sand at a speed of 12 parts / min. Then, 0.6 parts of stearic acid and 110 parts of anhydrous ethanol were mixed evenly and sprayed onto the surface of the medium sand at a speed of 12 parts / min. The mixture was dried under hot air at 70°C for 18 min and cooled to room temperature to obtain modified medium sand.

[0045] One part sodium citrate, 1.2 parts zinc lactate, and 0.4 parts sodium hydroxide were added to 160 parts deionized water and mechanically stirred at 420 rpm for 12 min. Then, 90 parts fly ash were slowly added and dispersed by stirring at 2300 rpm for 9 min. The mixture was then dispersed under ultrasonic conditions at 45 kHz for 25 min. The mixture was heated to 75 °C and stirred for 1.5 h. After centrifugation at 1200 rpm for 4 min, a wet material was obtained. The wet material was evenly spread in a tray and placed in a sealed container with a thickness of 6 mm. An open dish containing saturated Ca(OH)2 solution was placed at the bottom of the container to provide an alkaline air environment. The mixture was then hydrothermally aged at 90 °C for 1.5 h. The sample was then removed and dried at 105 °C for 1.5 h. After cooling to room temperature, the sample was passed through a 100-mesh sieve to obtain activated fly ash.

[0046] Mix 420 parts of P·O52.5 ordinary Portland cement, 90 parts of activated fly ash and 70 parts of modified silica fume, add 700 parts of modified medium sand and 850 parts of continuously graded crushed stone (particle size range of 5~20mm), and dry mix for 45s to obtain a mixed dry material.

[0047] Mix 210 parts of deionized water and 12 parts of polycarboxylate superplasticizer and stir until homogeneous to obtain a superplasticizer solution. Slowly add 2 / 3 of the superplasticizer solution to the mixed dry material and stir at 90 r / min for 120 s. Then add the remaining 1 / 3 of the superplasticizer solution and continue stirring for 120 s to obtain high-performance concrete.

[0048] High-performance concrete is poured onto a steel truss, compacted with a vibrating device, and cured for 25 hours to obtain high-performance concrete floor deck material.

[0049] Example 3

[0050] 2.0 parts of arabinose and 0.8 parts of glycine were added to 550 parts of deionized water, heated to 55°C, and mechanically stirred at 450 rpm for 20 min. 90 parts of silica fume were slowly added, and stirred at 2500 rpm for 10 min. The mixture was then dispersed under ultrasonic conditions at 50 kHz for 40 min and cooled to room temperature. The resulting mixture was poured into a spray dryer with an inlet air temperature of 180°C and an outlet air temperature of 90°C. The mixture was continuously spray-dried until the moisture content of the mixture reached 1 wt%. After cooling to room temperature, the mixture was passed through a 300-mesh sieve to obtain modified silica fume.

[0051] 700 parts of medium sand were poured into a roller spraying device and slowly rolled at 30 rpm at 35°C. 2 parts of ethyl metasilicate, 0.3 parts of ammonia (25 wt%) and 120 parts of anhydrous ethanol were mixed and stirred evenly, and then sprayed onto the surface of the medium sand at a speed of 15 parts / min. Then, 0.8 parts of stearic acid and 120 parts of anhydrous ethanol were mixed evenly and sprayed onto the surface of the medium sand at a speed of 15 parts / min. The mixture was dried under hot air at 75°C for 20 min and cooled to room temperature to obtain modified medium sand.

[0052] 1.2 parts sodium citrate, 1.5 parts zinc lactate, and 0.5 parts sodium hydroxide were added to 170 parts deionized water and mechanically stirred at 450 rpm for 15 min. 100 parts fly ash were slowly added and dispersed by stirring at 2500 rpm for 10 min. The mixture was then dispersed under ultrasonic conditions at 50 kHz for 30 min. The mixture was heated to 80℃ and stirred for 2 h. After centrifugation at 1500 rpm for 5 min, wet material was obtained. The wet material was evenly spread in a tray and placed in a sealed container with a thickness of 8 mm. An open dish containing saturated Ca(OH)2 solution was placed at the bottom of the container to provide an alkaline air environment. The mixture was hydrothermally aged at 95℃ for 2 h. The sample was then removed and dried at 105℃ for 3 h. After cooling to room temperature, the sample was passed through a 100-mesh sieve to obtain activated fly ash.

[0053] Mix 450 parts of P·O52.5 ordinary Portland cement, 100 parts of activated fly ash and 80 parts of modified silica fume, add 750 parts of modified medium sand and 900 parts of continuously graded crushed stone (particle size range of 5~20mm), and dry mix for 60s to obtain a mixed dry material.

[0054] Mix 220 parts of deionized water and 15 parts of polycarboxylate superplasticizer, stir evenly to obtain a superplasticizer solution, slowly add 2 / 3 of the superplasticizer solution to the mixed dry material, stir at 90 r / min for 120 s, then add the remaining 1 / 3 of the superplasticizer solution, and continue stirring for 150 s to obtain high-performance concrete.

[0055] High-performance concrete is poured onto a steel truss, compacted with a vibrating device, and cured for 26 hours to obtain high-performance concrete floor deck material.

[0056] Example 4

[0057] Add 1.5 parts arabinose and 0.6 parts glycine to 500 parts deionized water, heat to 50°C, mechanically stir at 400 rpm for 15 min, slowly add 80 parts silica fume, stir at 2000 rpm for 8 min, disperse under 40 kHz ultrasonic conditions for 30 min, cool to room temperature, pour the resulting mixture into a spray dryer, set the inlet air temperature to 170°C and the outlet air temperature to 85°C, continuously spray dry until the moisture content of the mixture reaches 1.5 wt%, cool to room temperature and pass through a 300-mesh sieve to obtain modified silica fume.

[0058] 650 parts of medium sand were poured into a roller spraying device and slowly rolled at 20 rpm at 30°C. 1 part of ethyl metasilicate, 0.1 part of ammonia (25 wt%) and 100 parts of anhydrous ethanol were mixed and stirred evenly and then sprayed onto the surface of the medium sand at a speed of 10 parts / min. Then, 0.5 parts of stearic acid and 100 parts of anhydrous ethanol were mixed evenly and sprayed onto the surface of the medium sand at a speed of 10 parts / min. The mixture was dried under hot air at 60°C for 15 min and cooled to room temperature to obtain modified medium sand.

[0059] Mix 400 parts of P·O52.5 ordinary Portland cement, 80 parts of fly ash and 60 parts of modified silica fume, add 650 parts of modified medium sand and 800 parts of continuously graded crushed stone (particle size range of 5~20mm), and dry mix for 30s to obtain the mixed dry material.

[0060] Mix 200 parts of deionized water and 10 parts of polycarboxylate superplasticizer, stir evenly to obtain a superplasticizer solution, slowly add 2 / 3 of the superplasticizer solution to the mixed dry material, stir at 60 r / min for 90 s, then add the remaining 1 / 3 of the superplasticizer solution, and continue stirring for 120 s to obtain high-performance concrete.

[0061] High-performance concrete is poured onto a steel truss, compacted with a vibrating device, and cured for 24 hours to obtain high-performance concrete floor deck material.

[0062] Example 5

[0063] 1.8 parts of arabinose and 0.7 parts of glycine were added to 520 parts of deionized water, heated to 53°C, and mechanically stirred at 420 rpm for 18 min. 85 parts of silica fume were slowly added, and the mixture was stirred at 2200 rpm for 9 min. The mixture was then dispersed under ultrasonic conditions at 45 kHz for 35 min and cooled to room temperature. The resulting mixture was poured into a spray dryer with an inlet air temperature of 175°C and an outlet air temperature of 85°C. The mixture was continuously spray-dried until the moisture content of the mixture reached 1.2 wt%. After cooling to room temperature, the mixture was passed through a 300-mesh sieve to obtain modified silica fume.

[0064] 700 parts of medium sand were poured into a roller spraying device and slowly rolled at 25 rpm at 32°C. 1.5 parts of ethyl metasilicate, 0.2 parts of ammonia (25 wt%) and 110 parts of anhydrous ethanol were mixed and stirred evenly and then sprayed onto the surface of the medium sand at a speed of 12 parts / min. Then, 0.6 parts of stearic acid and 110 parts of anhydrous ethanol were mixed evenly and sprayed onto the surface of the medium sand at a speed of 12 parts / min. The mixture was dried under hot air at 70°C for 18 min and then cooled to room temperature to obtain modified medium sand.

[0065] Mix 420 parts of P·O52.5 ordinary Portland cement, 90 parts of fly ash and 70 parts of modified silica fume, add 700 parts of modified medium sand and 850 parts of continuously graded crushed stone (particle size range of 5~20mm), and dry mix for 45s to obtain the mixed dry material.

[0066] Mix 210 parts of deionized water and 12 parts of polycarboxylate superplasticizer and stir until homogeneous to obtain a superplasticizer solution. Slowly add 2 / 3 of the superplasticizer solution to the mixed dry material and stir at 90 r / min for 120 s. Then add the remaining 1 / 3 of the superplasticizer solution and continue stirring for 120 s to obtain high-performance concrete.

[0067] High-performance concrete is poured onto a steel truss, compacted with a vibrating device, and cured for 25 hours to obtain high-performance concrete floor deck material.

[0068] Example 6

[0069] 2.0 parts of arabinose and 0.8 parts of glycine were added to 550 parts of deionized water, heated to 55°C, and mechanically stirred at 450 rpm for 20 min. 90 parts of silica fume were slowly added, and stirred at 2500 rpm for 10 min. The mixture was then dispersed under ultrasonic conditions at 50 kHz for 40 min and cooled to room temperature. The resulting mixture was poured into a spray dryer with an inlet air temperature of 180°C and an outlet air temperature of 90°C. The mixture was continuously spray-dried until the moisture content of the mixture reached 1 wt%. After cooling to room temperature, the mixture was passed through a 300-mesh sieve to obtain modified silica fume.

[0070] 700 parts of medium sand were poured into a roller spraying device and slowly rolled at 30 rpm at 35°C. 2 parts of ethyl metasilicate, 0.3 parts of ammonia (25 wt%) and 120 parts of anhydrous ethanol were mixed and stirred evenly and then sprayed onto the surface of the medium sand at a speed of 15 parts / min. Then, 0.8 parts of stearic acid and 120 parts of anhydrous ethanol were mixed evenly and sprayed onto the surface of the medium sand at a speed of 15 parts / min. The mixture was dried under hot air at 75°C for 20 min and then cooled to room temperature to obtain modified medium sand.

[0071] Mix 450 parts of P·O52.5 ordinary Portland cement, 100 parts of fly ash and 80 parts of modified silica fume, add 750 parts of modified medium sand and 900 parts of continuously graded crushed stone (particle size range of 5~20mm), and dry mix for 60s to obtain a mixed dry material.

[0072] Mix 220 parts of deionized water and 15 parts of polycarboxylate superplasticizer, stir evenly to obtain a superplasticizer solution, slowly add 2 / 3 of the superplasticizer solution to the mixed dry material, stir at 90 r / min for 120 s, then add the remaining 1 / 3 of the superplasticizer solution, and continue stirring for 150 s to obtain high-performance concrete.

[0073] High-performance concrete is poured onto a steel truss, compacted with a vibrating device, and cured for 26 hours to obtain high-performance concrete floor deck material.

[0074] The present invention also includes comparative examples and related experiments.

[0075] Comparative Example 1

[0076] The only difference from Example 1 is that arabinose was not added in step S1, while the other components and preparation steps were completely the same, resulting in a high-performance concrete floor deck material.

[0077] Comparative Example 2

[0078] The only difference from Example 1 is that glycine was not added in step S1, while the other components and preparation steps were completely the same, resulting in a high-performance concrete floor deck material.

[0079] Comparative Example 3

[0080] The only difference from Example 1 is that no modified silica fume was added in step S3. All other components and preparation steps are completely the same, and a high-performance concrete floor deck material is obtained.

[0081] Comparative Example 4

[0082] The only difference from Example 1 is that ethyl metasilicate was not added in step S2. All other components and preparation steps are completely the same, and a high-performance concrete floor deck material is obtained.

[0083] Performance testing:

[0084] The performance of high-performance concrete floor decking materials in Examples 1-6 and Comparative Examples 1-4 was tested. The fluidity of high-performance concrete was tested by slump test according to the national standard GB / T 50080-2016 "Standard for Test Method of Performance of Ordinary Concrete Mixture". The test results are shown in Table 1.

[0085] The strength properties of high-performance concrete were tested using the following method: High-performance concrete was prepared into cubic specimens of 150×150×150mm and prismatic specimens of 150×150×600mm. The compressive strength of the cubic specimens with curing ages of 1d, 3d, and 28d was tested according to the national standard GB / T 50081-2019 "Standard for Test Methods of Physical and Mechanical Properties of Concrete". The flexural strength of the prismatic specimens with curing ages of 1d, 3d, and 28d was tested according to the national standard GB / T 50081-2019 "Standard for Test Methods of Physical and Mechanical Properties of Concrete". The test results are shown in Table 1.

[0086] Table 1

[0087]

[0088] As can be seen from the data in Table 1, compared with Examples 4-6, the addition of activated fly ash in Examples 1-3 improved the compressive strength and flexural strength of the concrete specimens at 1 day and 3 days, indicating that the early strength of the concrete was improved.

[0089] As shown in Table 1, the 28-day compressive strength of Examples 1 to 6 is distributed in the range of 80.3 to 85.6 MPa, and the 28-day flexural strength is distributed in the range of 7.5 to 7.8 MPa, indicating that the high-performance concrete prepared by the present invention has good repeatability.

[0090] Based on the data in Table 1, it can be seen from Example 1 and Comparative Example 1 that, in Comparative Example 1, no arabinose was added in step S1, resulting in a significant decrease in the slump of the concrete, indicating reduced concrete fluidity. Based on the data in Table 1, it can be seen from Example 1 and Comparative Example 2 that, in Comparative Example 2, no glycine was added in step S1, resulting in a significant decrease in the slump of the concrete, indicating reduced concrete fluidity. Based on the data in Table 1, it can be seen from Example 1 and Comparative Example 3 that, in Comparative Example 3, no modified silica fume was added in step S3, resulting in a slight increase in the slump of the concrete, while the compressive and flexural strengths of the concrete specimens decreased. Based on the data in Table 1, it can be seen from Example 1 and Comparative Example 4 that, in Comparative Example 4, no ethyl metasilicate was added in step S2, resulting in a decrease in the slump of the concrete, indicating reduced concrete fluidity.

[0091] The above are preferred embodiments of the present invention. Those skilled in the art can make several improvements and modifications without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for preparing a high-performance concrete floor deck material, the concrete floor deck material comprising two parts: high-performance concrete and a steel truss, characterized in that, The preparation steps include the following: S1. Mix arabinose, glycine and deionized water, heat and stir, add silica fume, ultrasonically disperse, cool, spray granulate, dry, and sieve to obtain modified silica fume; S2. Mix ethyl metasilicate, ammonia and anhydrous ethanol evenly, spray the mixture onto the surface of medium sand, roll and stir, then spray stearic acid alcohol solution onto the surface of medium sand, dry and cool to obtain modified medium sand. S3. Mix cement, modified silica fume and fly ash, add modified medium sand and crushed stone, and dry mix to obtain a mixed dry material; S4. Mix deionized water and polycarboxylate superplasticizer, stir to prepare superplasticizer solution, slowly add part of the superplasticizer solution to the mixed dry material, stir, add the remaining superplasticizer solution, continue stirring until uniform, and obtain high-performance concrete; pour the high-performance concrete onto the steel truss, vibrate, and cure to obtain high-performance concrete floor deck material.

2. The method for preparing a high-performance concrete floor decking material according to claim 1, characterized in that, The fly ash is surface-treated with zinc lactate / sodium citrate and then subjected to alkaline wet heat aging to obtain activated fly ash.

3. The method for preparing a high-performance concrete floor decking material according to claim 2, characterized in that, The activated fly ash is prepared by mixing sodium citrate, zinc lactate, sodium hydroxide, and deionized water, stirring at 400-450 rpm for 10-15 minutes, adding fly ash, stirring at 2000-2500 rpm for 8-10 minutes, ultrasonically dispersing for 20-30 minutes, heating to 70-80℃ and stirring for 1-2 hours, centrifuging to dehydrate for 3-5 minutes to obtain wet material, placing the wet material in an alkaline air environment for humid heat aging, drying for 2-3 hours, cooling to room temperature, and then passing it through a 100-mesh sieve.

4. The method for preparing a high-performance concrete floor decking material according to claim 3, characterized in that, The steps of heating and aging the wet material in an alkaline air environment include: spreading the wet material evenly in a tray and placing it in a sealed container, placing a saturated Ca(OH)2 solution at the bottom of the sealed container, and heating the sealed container to 85~95℃ for aging for 1~2 hours; When the wet material is evenly spread into the tray, the thickness of the wet material is ≤8mm.

5. The method for preparing a high-performance concrete floor decking material according to claim 1, characterized in that, The modified silica fume is prepared by mixing arabinose, glycine, and deionized water, heating to 50-55°C, stirring at 400-450 rpm for 15-20 min, adding silica fume, stirring at 2000-2500 rpm for 8-10 min, ultrasonically dispersing for 30-40 min, cooling to room temperature to obtain a mixture, pouring the obtained mixture into a spray dryer, continuously spray drying until the moisture content of the mixture is ≤1.5 wt%, cooling to room temperature, and then passing it through a 300-mesh sieve.

6. The method for preparing a high-performance concrete floor decking material according to claim 1, characterized in that, Medium sand is poured into a roller spraying device and continuously rolled at a speed of 20-30 rpm at 25-35℃. Ethyl metasilicate, ammonia, and 100-120 parts by weight of anhydrous ethanol are mixed and stirred, and then sprayed onto the surface of the medium sand. Then, stearic acid alcohol solution is sprayed on, dried at 60-75℃ for 15-20 minutes, and cooled to room temperature to obtain modified medium sand.

7. The method for preparing a high-performance concrete floor decking material according to claim 1, characterized in that, Deionized water and polycarboxylate superplasticizer are mixed and stirred evenly to obtain a superplasticizer solution. Two-thirds of the superplasticizer solution is added to the mixed dry material and stirred at a speed of 60~90 r / min for 90~120s. The remaining superplasticizer solution is added and stirred for 120~150s to obtain high-performance concrete.

8. A high-performance concrete floor decking material, comprising high-performance concrete and a steel truss, characterized in that, The high-performance concrete is prepared by the preparation method of a high-performance concrete floor deck material according to any one of claims 1 to 7. The high-performance concrete comprises the following raw materials in parts by weight: 200 to 220 parts of deionized water, 10 to 15 parts of polycarboxylate superplasticizer, and 1990 to 2280 parts of mixed dry materials.

9. A high-performance concrete floor decking material according to claim 8, characterized in that, The mixed dry material comprises the following raw materials in parts by weight: 400-450 parts cement, 60-80 parts modified silica fume, 80-100 parts fly ash, 650-750 parts modified medium sand, and 800-900 parts crushed stone. The modified silica fume comprises the following raw materials in parts by weight: 1.5-2.0 parts arabinose, 0.6-0.8 parts glycine, 500-550 parts deionized water, and 80-90 parts silica fume; The modified medium sand comprises the following raw materials in parts by weight: 650-750 parts medium sand, 1-2 parts ethyl metasilicate, 0.1-0.3 parts 25wt% ammonia water, and 0.5-0.8 parts stearic acid.

10. A high-performance concrete floor decking material according to claim 9, characterized in that, The mixed dry material also includes 80-100 parts of activated fly ash, which comprises the following raw materials in parts by weight: 0.8-1.2 parts of sodium citrate, 1-1.5 parts of zinc lactate, 0.3-0.5 parts of sodium hydroxide, 150-170 parts of deionized water, and 80-100 parts of fly ash.

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