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CN-121990792-A - Anti-freezing concrete prefabricated part and preparation method thereof

CN121990792ACN 121990792 ACN121990792 ACN 121990792ACN-121990792-A

Abstract

The application relates to the technical field of building materials, and particularly discloses an antifreeze concrete prefabricated part and a preparation method thereof, wherein the antifreeze concrete prefabricated part comprises, by weight, 300-360 parts of cement, 40-60 parts of fly ash, 90-110 parts of mineral powder, 642-662 parts of natural sand, 1000-1100 parts of crushed stone, 7-9 parts of an additive, 150-170 parts of water, 0.5-1.5 parts of polypropylene alcohol fiber and 3-8 parts of phase-change self-repairing microcapsules. The prepared antifreeze concrete prefabricated part has the advantage of good antifreeze performance.

Inventors

  • XU HONGLING
  • SUN YUE

Assignees

  • 上海福铁龙住宅工业发展有限公司

Dates

Publication Date
20260508
Application Date
20260130

Claims (8)

  1. 1. The antifreeze concrete prefabricated part is characterized by comprising the following raw materials in parts by weight: 300-360 parts of cement, 40-60 parts of fly ash, 90-110 parts of mineral powder, 642-662 parts of natural sand, 1000-1100 parts of crushed stone, 7-9 parts of additive, 150-170 parts of water, 0.5-1.5 parts of polypropylene alcohol fiber and 3-8 parts of phase-change self-repairing microcapsule.
  2. 2. The antifreeze concrete prefabricated part of claim 1, wherein said phase change self-repairing microcapsule comprises 60-80 parts of semi-hydrated gypsum powder, 20-40 parts of organosilicon prepolymer, 25-35 parts of stearic acid, 0.05-0.15 part of platinum catalyst, 0.25-0.4 part of nano silicon dioxide and 0.02-0.05 part of diethyl maleate.
  3. 3. The antifreeze concrete prefabricated part according to claim 1, wherein said phase change self-repairing microcapsule preparation comprises the steps of: (1) Mixing and granulating semi-hydrated gypsum powder, organosilicon prepolymer, diethyl maleate and platinum catalyst to form wet particles with the particle size of 50-80 mu m; (2) Heating stearic acid to be completely liquefied, adding nano silicon dioxide, uniformly mixing, controlling the viscosity to be 200-300 mPa.s, atomizing, uniformly spraying on the surface of wet particles, and collecting particles with the particle size of 100-150 mu m to obtain the phase-change self-repairing microcapsule.
  4. 4. A precast element of antifreeze concrete as defined in claim 1, wherein said organosilicon prepolymer is vinyl-terminated polydimethylsiloxane.
  5. 5. The antifreeze concrete prefabricated part of claim 1, wherein the admixture comprises polycarboxylate water reducer 80-85wt%, air entraining agent 10-12wt% and retarder 5-8wt% of the total admixture.
  6. 6. A method for producing a precast element of antifreeze concrete as defined in any one of claims 1 to 5, comprising the steps of: Mixing cement, fly ash, mineral powder, natural sand and crushed stone, dry-mixing for 40-60s, adding water, additive and polypropylene alcohol fiber, stirring uniformly, adding phase-change self-repairing microcapsule, stirring at a reduced speed, and placing into a model for preliminary molding; and (3) carrying out steam curing on the preliminarily formed concrete, wherein the curing conditions are that the temperature is controlled to be 40-50 ℃, the humidity is more than or equal to 95%, and the frost-resistant concrete prefabricated part is obtained after curing for 6-8 hours.
  7. 7. The method for preparing the antifreeze concrete prefabricated part according to claim 1, wherein the steam cured concrete surface is sprayed with a super-hydrophobic layer, the super-hydrophobic layer comprises a silane coupling agent and fluorinated polysiloxane, and the weight ratio of the silane coupling agent to the fluorinated polysiloxane is 1:0.8-1.2.
  8. 8. The antifreeze concrete prefabricated part of claim 1, wherein said superhydrophobic layer is uniformly mixed with each raw material, and then uniformly sprayed on the surface of the concrete prefabricated part, and the spraying thickness is 700-900 μm.

Description

Anti-freezing concrete prefabricated part and preparation method thereof Technical Field The invention relates to the technical field of building materials, in particular to an antifreeze concrete prefabricated part and a preparation method thereof. Background In the field of construction engineering, concrete is an important building material, the performance of which plays a key role in the safety and durability of a building structure. With the continuous development of the building industry, the performance requirements on concrete are also higher and higher. In some cold areas, concrete structures face severe challenges of freeze-thaw damage, which not only affect the appearance of the building, but also reduce its load carrying capacity and service life. Therefore, the development of concrete materials with good frost resistance is an important research direction in the field of building materials. The appearance of the frost-resistant concrete prefabricated part provides a new way for solving the problem of freeze-thawing damage of concrete structures in cold areas, and has important significance for improving the quality and durability of constructional engineering. In conventional concrete preparation, various technical means are generally adopted in order to improve the performance of the concrete. For ordinary concrete, cement, sand, stones and water are generally used as basic raw materials, and certain strength requirements are met through reasonable mix proportion design. In order to improve the working performance of the concrete, additives such as water reducing agents, air entraining agents and the like are often added. When dealing with the frost resistance problem, it is common practice to mix a certain amount of mineral admixture such as fly ash, mineral powder, etc. into the concrete to improve the internal structure of the concrete and to improve the compactness and impermeability thereof. In addition, a method for adjusting aggregate grading is adopted, and proper natural sand and broken stone are selected to optimize the pore structure of the concrete and enhance the frost resistance of the concrete. However, these methods are often used alone or in simple combination, lacking comprehensive consideration of various factors. The prior art has obvious defects when preparing the frost resistant concrete prefabricated parts. The traditional concrete preparation method is difficult to meet the requirement of the concrete on the frost resistance in a cold environment. The common raw material mixing ratio and single technical means can not effectively solve the problem of internal damage of concrete in the freezing and thawing cycle process. For example, the freezing resistance of concrete cannot be fundamentally improved by only adding mineral admixture or adjusting aggregate gradation, and cracks and flaking are easily generated in the concrete after a plurality of freeze thawing cycles, resulting in the decrease of strength and durability. Therefore, a new technical solution is needed to improve the frost resistance of the concrete prefabricated parts. Disclosure of Invention The application provides an anti-freezing concrete prefabricated part and a preparation method thereof in order to improve the anti-freezing performance of the concrete prefabricated part. In a first aspect, the application provides an antifreeze concrete prefabricated part, which adopts the following technical scheme: a frost-resistant concrete prefabricated part comprises the following raw materials in parts by weight: 300-360 parts of cement, 40-60 parts of fly ash, 90-110 parts of mineral powder, 642-662 parts of natural sand, 1000-1100 parts of crushed stone, 7-9 parts of additive, 150-170 parts of water, 0.5-1.5 parts of polypropylene alcohol fiber and 3-8 parts of phase-change self-repairing microcapsule. By adopting the technical scheme, cement, fly ash and mineral powder form a gel system, cement hydration provides basic strength, secondary hydration reaction of the fly ash and mineral powder further fills pores, a structure is optimized, compactness and durability are improved, natural sand and broken stone form a reasonable grading framework, the bearing capacity of a member is enhanced, a proper amount of additive is used for adjusting the working performance of concrete, smooth construction is ensured, a random supporting system is formed by the polypropylene alcohol fiber in the concrete, micro-crack expansion is effectively restrained, partial internal stress caused by frost heaving or drying shrinkage is absorbed, crack generation and expansion probability is reduced, and phase change materials in the phase change self-repairing microcapsule can change when temperature changes, absorb or release heat, the internal temperature of the concrete is adjusted, and cracking caused by the temperature stress is reduced, so that the frost resistance and durability of the concrete prefabricated member are impro