Search

CN-122010489-A - Industrial solid waste high-strength concrete and preparation method thereof

CN122010489ACN 122010489 ACN122010489 ACN 122010489ACN-122010489-A

Abstract

The invention relates to the technical field of special low-carbon building materials, in particular to industrial solid waste high-strength concrete and a preparation method thereof, which aim to solve the problem that the existing photocatalytic concrete cannot ensure the photocatalytic performance and the mechanical performance simultaneously. The concrete matrix comprises, by weight, 550-650 parts of cement, 300-400 parts of a composite admixture, 600-700 parts of aggregate, 25-35 parts of a water reducing agent, 165-185 parts of water, 8-12 parts of modified copper-plated steel fibers, 1-3 parts of conductive fibers, wherein the composite admixture consists of 3-3 parts of fly ash, 2-2 parts of silica fume and 1-2 parts of catalyst-carried yellow phosphorus slag micro powder in a mass ratio, the modified copper-plated steel fibers comprise copper-plated steel fibers with conductive polymers wrapped on the surfaces, and the surface functional film is a hydrophobic photocatalytic composite film formed by in-situ reaction of a silicon-based penetrating agent on the surface of the concrete. According to the invention, the synchronous optimization of the photocatalytic purification performance and the structural mechanical performance is realized by the combined action of the composite admixture, the modified copper-plated steel fiber, the conductive fiber and the surface functional film in the system.

Inventors

  • ZHAO ZHIGUANG
  • QU XIAOLING
  • TIAN CHANGAN
  • LI ZAIBO
  • LI FANGXIAN

Assignees

  • 韶关学院
  • 华南理工大学

Dates

Publication Date
20260512
Application Date
20260123

Claims (10)

  1. 1. The industrial solid waste high-strength concrete is characterized by comprising a concrete matrix and a surface functional film; The concrete matrix comprises, by weight, 550-650 parts of cement, 300-400 parts of a composite admixture, 600-700 parts of aggregate, 25-35 parts of a water reducer, 165-185 parts of water, 8-12 parts of modified copper-plated steel fibers and 1-3 parts of conductive fibers; The composite admixture consists of 3-4 parts by mass of fly ash, 2-3 parts by mass of silica fume and 1-2 parts by mass of catalyst-loaded yellow phosphorus slag micropowder; The modified copper-plated steel fiber comprises a copper-plated steel fiber coated with a conductive polymer on the surface; the conductive fibers are selected from carbon fibers or copper fibers; the surface functional film is a hydrophobic photocatalytic composite film formed by in-situ reaction of a silicon-based penetrating agent on the surface of concrete.
  2. 2. The industrial solid waste high-strength concrete according to claim 1, wherein, The preparation method of the composite admixture comprises the following steps: (1) Ball milling yellow phosphorus slag until the specific surface area is more than or equal to 750m <2 >/kg and D50 is less than or equal to 8 mu m; (2) Dissolving tetrabutyl titanate in ethanol to obtain a uniform organic titanium source solution, dissolving ammonium cerium nitrate in deionized water to obtain an inorganic cerium source solution, slowly dripping a cerium salt aqueous solution into a stirred titanium alkoxide alcoholic solution, wherein the molar ratio of titanium to cerium is (3:1) - (1:1); (3) Immersing the micro powder in the step (1) in the solution in the step (2) for 2-4 hours by adopting vacuum auxiliary immersion, wherein the solid-liquid ratio is 1:8-12; (4) Drying at 80-100 ℃ after taking out, and calcining at 450-550 ℃ for 2-3 hours to obtain the catalyst-carrying micro powder loaded with TiO 2 -CeO 2 heterojunction.
  3. 3. The industrial solid waste high-strength concrete according to claim 2, wherein the preparation method of the modified copper-plated steel fiber is as follows: (1) Sequentially carrying out alkali washing degreasing, acid washing activation and silane coupling agent treatment on the copper-plated steel fibers, wherein the addition amount of the silane coupling agent is 1% -3% of the mass of the aniline monomer; (2) Dispersing the pretreated fibers in an ammonium persulfate aqueous solution, wherein the molar ratio of ammonium persulfate to aniline monomer is 1:1, preparing the ammonium persulfate into an aqueous solution with the concentration of 0.5-1.0 mol/L, and reacting for 12-24 hours; (3) The fiber with the surface covered with the eigenstate polyaniline after the polymerization reaction is soaked in 0.5-1.0 mol/L of p-toluenesulfonic acid solution for 2-3 hours under the protection of nitrogen, the temperature rising rate is 2 ℃ per minute, and the heat preservation time is 60 minutes.
  4. 4. The industrial solid waste high strength concrete as claimed in claim 3, wherein the copper-plated steel fiber has a diameter of 0.18-0.22mm, a length of 12-16mm, and a copper-plated layer thickness of 1-3 μm.
  5. 5. The industrial solid waste high-strength concrete according to claim 4, wherein, The penetrating fluid comprises, by mass, 15-25 parts of alkyl alkoxy silane, 10-15 parts of nano SiO 2 sol, 2-5 parts of tetrabutyl titanate, 55-65 parts of ethanol and 0.5-1 part of catalyst; mixing the alkylalkoxysilane, tetrabutyl titanate and part of the ethanol, stirring uniformly to obtain a solution A, mixing the nano SiO 2 sol, the catalyst and the rest of the ethanol, stirring uniformly to obtain a solution B, slowly adding the solution B into the solution A under the stirring condition, and mixing uniformly to obtain the penetrating fluid.
  6. 6. The industrial solid waste high-strength concrete according to claim 5, wherein, The thickness of the surface functional film is 0.1-0.3mm.
  7. 7. The industrial solid waste high-strength concrete according to claim 6, wherein, The cement is silicate cement or ordinary silicate cement.
  8. 8. The industrial solid waste high-strength concrete according to claim 7, wherein, The aggregate is quartz sand, the maximum grain diameter of the aggregate is not more than 2.36mm, and the fineness modulus is 2.3-2.8.
  9. 9. The industrial solid waste high-strength concrete according to claim 8, wherein, The water reducer is a polycarboxylic acid high-performance water reducer.
  10. 10. A method for preparing industrial solid waste high-strength concrete according to any one of claims 1 to 9, comprising the steps of: (1) Preparing a catalyst-loaded yellow phosphorus slag micropowder and modified copper-plated steel fibers; (2) Mixing and stirring, namely weighing cement, composite admixture and quartz sand according to the proportion, dry-mixing, adding water and a water reducing agent, stirring to form uniform slurry, slowly adding modified copper-plated steel fibers, and continuously stirring until the fibers are uniformly dispersed; (3) Pouring and curing, namely pouring the mixture into a mold coated with a release agent, vibrating and compacting, covering a plastic film, curing and demolding, and continuing standard curing until the age of 7-14 days after demolding; (4) Surface treatment, namely cleaning the surface of concrete, brushing penetrating fluid, and curing, wherein direct contact with water is avoided during curing; (5) And (3) curing the finished product, namely after the surface functional film is formed, continuing standard curing for 28 days or the required age.

Description

Industrial solid waste high-strength concrete and preparation method thereof Technical Field The invention relates to the technical field of special low-carbon building materials, in particular to industrial solid waste high-strength concrete and a preparation method thereof. Background Photocatalytic concrete is of great interest because of its characteristic of degrading air pollutants. The prior art mainly realizes the photocatalysis function by doping nano titanium dioxide and other photocatalysts into concrete or coating the surface of the concrete. However, the method has a plurality of obvious defects that on one hand, in the internally doped type photocatalytic concrete, the photocatalyst is wrapped in a cement matrix, is not fully contacted with polluted gas, and the photo-generated electron-hole pair is easy to compound, so that the catalytic efficiency is low, on the other hand, the interface binding force between the externally coated type photocatalytic coating and the concrete matrix is weak, the external coating type photocatalytic coating is easy to peel off under the service environment such as temperature and humidity change, freeze thawing cycle and the like, and the function durability is poor. In order to improve the photocatalytic efficiency, there are studies on the introduction of conductive components such as carbon fibers, graphene and the like into concrete to construct a rapid charge transfer channel and inhibit electron-hole recombination. However, the conductive material is often poor in compatibility with a cement matrix, easy to agglomerate and uneven in distribution, and the mixing of the conductive material often leads to the reduction of the workability and the damage of the mechanical property of concrete, and even introduces hidden danger of durability. In addition, the existing conductive reinforcing material has single function, and is difficult to simultaneously meet the synergistic requirements of structural reinforcement, charge conduction and long-term durability. In the aspect of concrete reinforcing fiber, although the toughness and crack resistance of the concrete can be obviously improved by the traditional steel fiber, the surface of the steel fiber is easy to corrode, the interface combination with a cement matrix is weaker, and the long-term performance is easy to degrade. Although modification treatments such as copper plating and polymer coating are performed on the surface of the fiber so as to improve the durability or give a certain function, the modified layer is often not firmly combined with the fiber matrix, is easy to peel and lose efficacy under complex stress and chemical environment of concrete, has complicated modification process, and is difficult to integrate and stabilize the multifunctional environment. Therefore, developing a novel composite material system which can not only effectively improve the photocatalytic performance of concrete, but also synchronously enhance the mechanical performance and durability of the concrete and has a synergistic effect among all functional components becomes a key technical problem to be solved in the field. Disclosure of Invention The invention provides an industrial solid waste high-strength concrete and a preparation method thereof, which are used for effectively improving the photocatalysis performance of the concrete, synchronously enhancing the mechanical property and durability of the concrete and having a synergistic effect among functional components. In order to alleviate the technical problems, the technical scheme provided by the invention is as follows: an industrial solid waste high-strength concrete comprises a concrete matrix and a surface functional film; The concrete matrix comprises, by weight, 550-650 parts of cement, 300-400 parts of a composite admixture, 600-700 parts of aggregate, 25-35 parts of a water reducer, 165-185 parts of water, 8-12 parts of modified copper-plated steel fibers and 1-3 parts of conductive fibers; The composite admixture consists of 3-4 parts by mass of fly ash, 2-3 parts by mass of silica fume and 1-2 parts by mass of catalyst-loaded yellow phosphorus slag micropowder; The modified copper-plated steel fiber comprises a copper-plated steel fiber coated with a conductive polymer on the surface; the conductive fibers are selected from carbon fibers or copper fibers; the surface functional film is a hydrophobic photocatalytic composite film formed by in-situ reaction of a silicon-based penetrating agent on the surface of concrete. Still further, the method further comprises the steps of, The preparation method of the composite admixture comprises the following steps: (1) Ball milling yellow phosphorus slag until the specific surface area is more than or equal to 750m <2 >/kg and D50 is less than or equal to 8 mu m; (2) Dissolving tetrabutyl titanate in ethanol to obtain a uniform organic titanium source solution, dissolving ammonium cerium nitrate in deionized